chapter 4.1 hydrology and water quality...university of california, davis 4.1-1 october 1996 chapter...

WWTP Replacement Project Draft EIRUniversity of California, Davis October 19964.1-1

Chapter 4.1 Hydrology and Water Quality

INTRODUCTION

This chapter addresses impacts of the project on local and regional hydrologic characteristics, includingdrainage and groundwater recharge, and on surface water and groundwater quality. Chapter 4-3,“Hazardous Materials and Public Safety”, contains an evaluation of hazardous materials and microbialcontaminant issues related to the project.

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), this analysisfocuses on the potential impacts related to absorption rates; volume of surface water runoff, and drainagepatterns; potential water quality effects on surface water and groundwater, volume of water bodies; andwater movements. Potential impacts related to public availability of groundwater were adequatelyaddressed by the 1994 LRDP EIR.

ENVIRONMENTAL SETTING

Surface Water Hydrology

Putah Creek

The largest surface waterway in the vicinity of the Campus is Putah Creek, which drains an areaof approximately 600 square miles, and extends 80 miles from the Coast Ranges to the Yolo Bypass andultimately to the Sacramento River. Flow in Putah Creek is substantially regulated by the Solano Project,which includes a large storage reservoir behind Monticello Dam (Lake Berryessa; capacity 1,600,000 acre-feet [af]), a rediversion dam about 18 miles upstream of Davis (the Putah Diversion Dam), and a distributionsystem to deliver water to agricultural and municipal users in Solano County (Figure 4.1-1). UC Davis alsoreceives an allocation of water (4,000 acre-feet per year [af/yr]) from the Solano Project. The SolanoProject consists of Lake Berryessa, the Putah Diversion Dam, and the Putah South Canal, which are usedto distribute water supplies to downstream municipal and agricultural areas.

The terrain along Putah Creek downstream of the Putah Diversion Dam is fairly flat and generallyslopes away from the creek channel. There are relatively small areas along the channel that drain towardthe creek and contribute some flow in winter, however. These areas include portions of the Campus.


Putah Creek was rerouted in the late 1800s by local residents, beginning at a point about 3,000 feetupstream of Interstate 80 (I-80). The new channel, called the South Fork of Putah Creek, now conveysall the upstream flows. The old channel, or North Fork Cutoff, passes through the Campus and consistsof several segments, including the Arboretum Waterway. The North Fork Cutoff is hydraulically isolatedfrom Putah Creek and receives no inflows from upstream reaches of the creek.

The South Fork of Putah Creek along the reach near the Campus consists of a low-flow channeltypically 4-10 feet deep and 30-150 feet wide located between flood control levees about 500-800 feetapart. There is a low terrace within the levees and adjacent to the low-flow channel along most of thecreek. From about 1 mile upstream of I-80 to Old Davis Road, the terrace is 300-500 feet wide. Vegetation clearing was extensive prior to the 1980s. The creek channel along the reach bordered by theCampus is now managed as a natural reserve, and vegetation clearing to maintain flood conveyancecapacity is more selective. Vegetation on the terraces consists largely of grassland with scattered trees andshrubs, whereas the low-flow channel is bordered by a band of relatively thick shrubs and trees.

A streamflow gauging station has been in operation at Old Davis Road since 1959, but there areperiods of missing records when operation of the gauge was transferred among several agencies. Reliableflow records are readily available only through 1985. Minimum, median, average, and maximum monthlyflows during 1971-1985 are shown in Table 4.1-1. This period of analysis was wetter than average, butit reflects constant operation of the Solano Project under a schedule of releases adopted in 1970. Thesereleases ranged from 15-46 cfs, measured at Putah Diversion Dam.

Following years of litigation, a judgement was issued in the Putah Creek Water Cases in August1996. Pursuant to this judgement, future releases from the Putah Diversion Dam would be required to meetthe mean daily flows shown in Table 4.1-1 at Stevenson Bridge, Pedrick Road, I-80, and Old Davis Road. Minimum permissible instantaneous flows, which are also shown in Table 4.1-1, equal about 90% of therequired mean daily flows. The judgement issued in these cases is subject to appeal, and it is unknown if,or when, new flow requirements might take affect.

During the dry season (typically April-October), much of the water released from Putah DiversionDam percolates into the creekbed or is diverted for irrigation use by riparian landowners before it reachesDavis. Consequently, streamflow under the 1970 release schedule sometimes ceased along the reach nearDavis. This occurred, for example, in 1972, 1976-1977, 1989, 1990-1991, and 1992. Even in normalyears, much of the flow recorded at the Old Davis Road bridge during the dry season consisted of thedischarge from the WWTP. For example, in 8 of the 15 years during 1971-1985, the monthly averageflow was less than 4 cfs in September, of which up to 2.5 cfs was derived from the WWTP dischargeimmediately upstream of the gauge.

During the wet season (November-March), unregulated runoff below Lake Berryessa often resultsin temporary flows substantially in excess of the scheduled releases from Putah Diversion Dam. Forexample, a major storm event in early January 1995 generated an average daily flow of 1,050 cfs at PutahDiversion Dam, and all but 10 cfs of the flow was derived from runoff below Lake Berryessa. In yearswhen Lake Berryessa spills, high flows can persist for weeks or months. Lake Berryessa spilled in 1996

Table 4-1.1. Monthly Flows in the South Fork of Putah Creek near Davis (1971-1985) and Court-Ordered Minimum Flows

Oct(cfs)

Nov(cfs)

Dec(cfs)

Jan(cfs)

Feb(cfs)

Mar(cfs)

Apr(cfs)

May(cfs)

Jun(cfs)

Jul(cfs)

Aug(cfs)

Sep(cfs)

Annual Total (af)

Actual Flows 1971-1985

Minimum 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0

Median 6.0 11.0 17.1 162.0 151.0 228.8 65.6 37.4 18.9 14.1 7.9 3.1 72,366

Average 8.1 19.9 117.6 351.4 421.0 939.0 624.7 69.4 22.8 16.0 10.9 5.6 159,514

Maximum 31.2 61.9 1,350.0 1,500.0 3,680.0 6,830.0 4,654.0 543.0 71.3 50.1 33.9 27.4 829,996

1996 Court-ordered Flows

Mean Daily Flow 5 10 10 15 15 25 30 20 15 15 10 5 n.a.

Instantaneous 4.5 9 9 13.5 13.5 22.5 27 18 13.5 13.5 9 4.5 n.a.

Notes: The 1971-1985 period was 12.5% wetter than the long-term average, based on a 120-year record of rainfall at Davis. Base flow releases from PutahDiversion Dam during 1971-1985 followed the 1970 release schedule.

cfs = cubic feet per secondaf = acre feetn.a. = not applicable

Sources: Actual flow data obtained from records of the U.S. Geological Survey and California Department of Water Resources; 1996 court-ordered flowsobtained from Judgement - Putah Creek Water Cases.


for the first time in 10 years. The 100-year peak flood flow in the South Fork of Putah Creek isapproximately 30,000 cfs, based on simulated routing of a 100-year rainstorm event through the LakeBerryessa spillway and the channel between Monticello Dam and Davis. Two separate studies of floodflows along lower Putah Creek indicated that the 100-year flood flow would not overtop the levees but thatthere would be little freeboard (Jones & Stokes Associates 1992; Cowan pers. comm.).

The occurrence of no-flow periods is important to the analysis of water quality impacts associatedwith discharges because it means there are times when discharges are not diluted at all upon entering thecreek. Although, if implemented, the new court-ordered requirements for instream flows should preventflows from ever dropping below 4.5 cfs, there is a remote possibility that a period of no flow could resultfrom unintended fluctuations in operation of Putah Diversion Dam and riparian diversion pumps, beaveractivity, or unforeseen in-channel activities upstream of the Campus. In addition, it is unknown if or whenthe 1996 court-ordered flow requirements would be implemented; implementation depends on the outcomeof the appeal process if the judgement is appealed. Consequently, the impact analysis described later inthis chapter includes an evaluation of water quality impacts under no-flow conditions.

The reach of the South Fork of Putah Creek in the vicinity of the Campus is a losing reach. Acompilation of various instantaneous and continuous streamflow measurements from Pedrick Road, I-80,Old Davis Road, and Mace Boulevard collected over a period of several decades by the U.S. GeologicalSurvey (Thomasson et al. 1960), the California Division of Water Resources (1955), Solano IrrigationDistrict (Sanders pers. comm.), and the Putah Creek Council (Sanders pers. comm.) indicates that seepagelosses range from about 0.5 cfs per mile in winter in wet years to 1.2 cfs per mile in summer in dry years.

Existing Campus Discharges

There are four wastewater discharges from Campus facilities (the existing WWTP, the PutahCreek Research Facility, the Aquatic Center, and the U.S. Department of Agriculture [USDA] AquaticWeed Control Laboratory), storm water discharge from the Arboretum Waterway, and one potentialdischarge along the 3-mile reach upstream of the WWTP discharge (Figure 4.1-2). Existing conditions ateach upstream discharge are described in this section. In addition, there are two storm water dischargesdownstream of Old Davis Road bridge and one discharge upstream of the bridge from a small lift stationat the LEHR/SCDS area. These discharges are described in Chapter 7, “Effects Related to the Laboratoryfor Energy-Related Health Research and the South Campus Disposal Site”.

Existing WWTP. The average annual discharge from the existing WWTP during 1992-1996 was2.44 cfs, or 1.58 mgd. The average discharge rate during the first half of 1996 was 2.57 cfs, or 1.66 mgd. Average monthly flows range from 1.8 to 3.0 cfs. The minimum and maximum daily flows during 1992-1996 were approximately 1.1 and 4.3 cfs, or 45% and 176% of the average annual flow, respectively. Theproposed WWTP discharge would be at the same location and would have similar daily and seasonalpatterns of flow rates.

Putah Creek Research Facility. This facility, also known as the fish hatchery, is located about0.25 mile upstream of Pedrick Road and 3.0 miles upstream of the WWTP discharge at Old Davis Road.


The facility, which is operated by the UC Davis Aquaculture and Fisheries program, conducts a wide rangeof research on fish ecology, nutrition, and reproduction. The discharge into Putah Creek from this facilityis measured. Monthly monitoring reports prepared by the University indicate that typical dry season flowrates are 0.3-0.9 cfs, and winter flows are often 20-30% greater.

Aquatic Center. The Aquatic Center is also a fisheries research facility under the UC DavisAquaculture and Fisheries program. The discharge from this facility enters Putah Creek near the south endof Hopkins Road, 1.0 mile upstream of Old Davis Road. The discharge from this facility is measured, andmonthly average flow ranges from 0.5-1.0 cfs with no clear seasonal pattern.

USDA Aquatic Weed Control Laboratory. This facility is located at the split between the northand south forks of Putah Creek, 2.0 miles upstream of Old Davis Road. The facility conducts research onaquatic plant herbicides, plant interaction and competition, and fish culture. The discharge is not measured,but is relatively small. For this analysis, the discharge is conservatively estimated to equal the maximumpermitted discharge during the dry weather period of 0.077 cfs.

Central Campus Storm Water Outfall. A storm water pumping pond and lift station #4 arelocated in the North Fork Cutoff immediately west of the western end of the Arboretum Waterway. Thepumping pond receives runoff from the Central Campus area via the Arboretum Waterway and from theWest Campus area via the North Fork Cutoff and a siphon under Highway 113. The lift station has fourpumps with a combined capacity of 53.5 cfs that pump storm water from the collection pond in the channelthrough a pipeline 1,000 feet to the South Fork of Putah Creek. During the dry season, the storm waterpumping pond receives overflow from the Arboretum Waterway, which occurs when inflows (principallyirrigation runoff from the Arboretum and Central Campus areas) exceed seepage and evaporation lossesfrom the Arboretum Waterway. Prior to May 1996, inflow to the Arboretum Waterway includedblowdown water from approximately 32 cooling towers in Central Campus buildings, in accordance withan NPDES permit. During that period, dry season overflow from the Arboretum Waterway averaged 0.14cfs (Connors and Darby 1991).

Discharge from the storm water pumping pond is much greater during winter rainstorms. The peakflows for 10-year and 100-year 12-hour storm events are approximately 88 and 151 cfs, respectively(Morton and Pitalo 1991). Peak flows are substantially moderated by storage effects in the ArboretumWaterway and the North Fork Cutoff pond west of Highway 113. The discharge pipeline from the stormwater pumping pond to the South Fork of Putah Creek is 54 inches in diameter and can convey more thanthe present pumping capacity of 53.5 cfs. The lift station is permitted for a discharge of up to 130 cfs, andthere is room at the facility to install additional pumps.

The combined dry season flow from the four existing permitted upstream discharges totals about2.6 cfs, or approximately the same amount of flow as the existing WWTP discharge.


Potential Future Discharge

Landfill Groundwater Remediation Program. Contaminated shallow groundwater near theUniversity landfill immediately west of Pedrick Road and north of Putah Creek (2.8 miles upstream of OldDavis Road) is being pumped from the ground and treated to remove organic pollutants such as chloroform. Since October 1995, the treated water has been routed to the existing WWTP for additional treatment anddischarge via the existing WWTP outfall. However, the University has obtained an NPDES permit fromthe CVRWQCB to discharge the treated landfill groundwater directly to the creek. The maximumpermitted discharge is 0.36 cfs or 0.23 mgd.

Drainage at the Proposed WWTP Site

The proposed WWTP site is presently used as pasture by the California Center for Equine Healthand Performance (CCEHP). The land slopes gently to the northeast from a maximum elevation of about48 feet above sea level to a minimum elevation of about 46 feet. Site drainage was evaluated in a study byNolte & Associates (1996). Rainfall runoff from the site flows across the pasture in an easterly directionto a ditch on the east side of the pasture, which collects in shallow culverts (Markel pers. comm.), and thendischarges into a north-south drainage ditch that conveys the water 1,800 feet to the South Fork of PutahCreek. A short, gated, 30-inch pipe through the levee allows the ditch to drain by gravity to the creek. Thepipeline through the proposed WWTP site also conveys storm water runoff from the Animal ResourcesService facility across the Southern Pacific Railroad tracks from the site. The capacity of the pipeline isestimated to be 6.3 cfs (Nolte & Associates 1996).

Groundwater Resources

The Campus and the South Fork of Putah Creek overlie the deep alluvial groundwater basin thatextends more or less continuously throughout the Sacramento Valley. The project area is in the lowerCache-Putah basin, which is a subunit of the overall basin and extends from the Plainfield Ridge(approximately 8 miles west of the Campus) to the Sacramento River (approximately 15 miles east of theCampus). The basin fill consists of discontinuous layers of unconsolidated sediments of variable textureranging from clay to gravel. The coarser deposits form aquifers and provide almost all the water supply forUC Davis and the City of Davis. The City of Davis obtains all its municipal water supply from 21 wellslocated throughout the city with depths of 330-615 feet (University of California, Davis 1994). Only oneof these wells taps into the deep aquifer (700-1500 feet below the surface), while the others draw waterfrom the shallow intermediate aquifer (200-600 feet below the surface). Campus Domestic Well No. 4 islocated approximately 400 feet from the southwest corner of the proposed WWTP site. It has a depth ofapproximately 1,300 feet, with perforations only below a depth of about 300 feet (Markel pers. comm.).Additionally, the Campus has five wells with depths of 322-470 feet that supply utility water. Theshallowest zone used for significant water production is the basal gravel of the older alluvium unit, which isat a depth of about 130 feet near Davis (Thomasson et al. 1960).


Shallow stratigraphy has not been investigated at the proposed WWTP site but has been studiedin detail at the LEHR/SCDS area south of the proposed WWTP site (Dames & Moore 1995; PacificNorthwest National Laboratory 1996). The subsurface materials are alluvium deposited at the distal edgeof the Putah Creek fan during the Pliocene and Pleistocene epochs. From the ground surface to a depthof about 80 feet, the sediments consist of clays and silts with interbedded lenses of sands and gravels. Thepart of this unit below the water table is called hydrostratigraphic unit one (HSU-1). The water tabletypically fluctuates about 25 feet seasonally, with low levels in July-August and high levels in March. Weekly water-level measurements at 13 SCDS monitoring wells since 1990 indicated that the water tablewas lowest (about 70 feet below land surface) in summer 1991 and summer 1994, and it was highest (lessthan 30 feet below land surface) in March 1995 after an extremely wet winter (approximately 175% ofnormal rainfall). There was 40 feet of water level recovery during the winter of 1995.

Beneath HSU-1 is a second hydrostratigraphic unit (HSU-2) consisting of 30-55 feet of sand andgravel deposits. Beneath HSU-2 is the relatively fine-grained Tehama Formation, which is hundreds of feetthick and, although less permeable than the overlying alluvium, is a major component of the groundwatersystem tapped by many water supply wells throughout the southwestern Sacramento Valley. Water levelsin HSU-2 are up to 2 feet lower than in HSU-1 during the irrigation season (April-September) as a resultof pumping from HSU-2 and deeper aquifers by nearby irrigation wells. The gradient reverses andbecomes slightly upward during September-November as the vertical profile of hydraulic head readjustsitself following the irrigation season.

Water level contour plots for HSU-1 and HSU-2 in 1994 (a dry year) and 1995 (a wet year)indicate that the direction of groundwater flow is predominantly easterly with a slight northerly componentthat increases in wet years (Pacific Northwest National Laboratory 1996). In February 1995, for example, the direction of flow in HSU-1 was almost due north. These results indicate that shallow groundwaterflows approximately parallel to the boundary between the LEHR/SCDS area and the proposed WWTPsite (eastward) in dry years, from LEHR/SCDS to the WWTP site (northward) in wet winters, and in anintermediate direction (more or less northeastward) under less extreme conditions. It appears thatgroundwater rarely, if ever, flows from the proposed WWTP site toward the LEHR/SCDS area.

The water table level is lower than the creekbed along the South Fork of Putah Creek, indicatingthat creek water can percolate down to the water table but groundwater does not seep into the creek. Theelevation of the bed of the South Fork of Putah Creek (22 feet above sea level) approximately equals themaximum water level recorded in the LEHR/SCDS monitoring wells during 1990-1995 (Pacific NorthwestNational Laboratory 1996). The water level in the creek is maintained above the creekbed because ofexisting flow or ponding of WWTP discharge in drier periods. Therefore, the water level in the creek isessentially always higher than the adjacent shallow water table, and seepage is always out of the creek. During wet winters when groundwater levels are exceptionally high, the creek water may be hydraulicallycoupled to groundwater. Under these circumstances, the rate of seepage loss from the creek is affectedby the level of the water table. In general, the groundwater table is probably too low for there to be acontinuous zone of saturation between the creek and the water table. In this case, an unsaturated zoneforms between the creek and the water table, and the rate of seepage out of the creek is not affected bythe water table elevation.


Surface Water Quality

This section describes the water quality conditions in the South Fork of Putah Creek and ingroundwater in the LEHR/SCDS area. Major factors affecting water quality include off-Campus drainage,Campus storm drainage, pumped discharges from the Arboretum Waterway, and permitted discharges fromthe Campus wastewater treatment plant (WWTP) and other research facilities. Water quality conditionsassociated with the LEHR/SCDS area are also addressed as they relate to the proposed WWTP site. Adescription of the LEHR/SCDS area is presented in Chapter 7.

Overview of Water Quality in the South Fork of Putah Creek

Water quality in the South Fork of Putah Creek, particularly during summer and below the existingWWTP discharge outfall, is determined to a large extent by the quality of surface water drainage from theCampus. Also, physical conditions of the creek, such as shading and water temperature, are important tothe health of fish and other aquatic organisms during summer. Most of the streamflow in the South Forkof Putah Creek during summer consists of WWTP effluent and other Campus discharges. Storm drainageconsists primarily of overflow from the Arboretum Waterway, wash water from barns and other Campusareas, and landscape maintenance activities. Operation and maintenance activities play a major role in thewater quality of the Campus drainage. The relative effect of the existing WWTP effluent on the creekdepends in part on the water quality and quantity of flow in the receiving water body above the WWTPdischarge.

Water quality conditions vary with the season, particularly in summer when streamflows are minimaland there is little rainfall runoff to dilute pollutants that enter the stream channel. Near the WWTP outfallin the middle of summer, the stream in the recent past consisted of ponded water with little or no flow. During summer flow conditions, water quality in the South Fork of Putah Creek can be characterized byphysical conditions of temperature, dissolved oxygen, and turbidity; pollutants such as coliform bacteria,ammonia, and biostimulatory nutrients (e.g., nitrogen, phosphorus); and nuisance conditions such as algaegrowth and odors. During winter, streamflow in the South Fork of Putah Creek is much higher and isinfluenced more by storm water runoff. Water quality in winter is influenced by overland transport duringstorm events of pollutants such as sediments from soil erosion and construction sites, oils and grease fromautomobiles and paved areas, nutrients from agricultural fields and livestock boarding areas, and organiclitter (e.g., leaves and grass clippings).

Water Quality Upstream of the Campus. Essentially no data exist for the water quality of PutahCreek upstream of the Campus prior to 1995. Water samples were collected in fall 1995 to characterizeambient water quality upstream of the Campus (University of California, Davis 1995a). Three sampleswere collected in Putah Creek at the western boundary of the Campus over the course of 3 weeks priorto fall rains. The samples were analyzed for conventional inorganic parameters (e.g., dissolved oxygen[DO], specific conductance, pH, temperature), major inorganic ions (e.g., sulfate, nitrate, chloride), selectedtrace metals, volatile and semivolatile organic compounds, organophosphorus and chlorinated pesticides,


purgeable aromatics and halocarbons, and phenols. The sample results indicate that only four trace metalswere detected, including arsenic (three of three samples), beryllium (one of three samples), total chromium(three of three samples), and copper (two of three samples) (Table 4.1-2). Only one organic compound(tributyltin) was detected on only one sample date.

Locations and Water Quality of Nonpermitted and Miscellaneous Discharges. Severaldischarges contribute a substantial amount of flow to the South Fork of Putah Creek but their dischargesare not regulated under current law nor monitored for water quality. Applicable discharges include overflowfrom the Arboretum Waterway that is pumped from the Central Campus pumping pond and miscellaneousstorm water inputs.

Arboretum Waterway. A significant contribution of flow to the South Fork of PutahCreek is derived from the Arboretum Waterway, which is located in the south end of the Central Campus(Figure 4.1-2). The Arboretum Waterway was constructed in 1969 as a shallow 10-acre pond within theconfines of the historic channel of the North Fork of Putah Creek. Flow through the 10-acre pond is fromthe east-end control dam near downtown Davis to the west-end dam east of Highway 113. Overflow fromthe Arboretum Waterway then drains west to a Central Campus pumping pond and is pumped to the SouthFork of Putah Creek approximately 0.25 mile upstream of the location of the WWTP outfall. The volumeof flow through the pumping pond depends on the season and consists of storm water runoff from theCampus that discharges through numerous storm drains. Overflow from the Arboretum Waterway isapproximately 0.10 cfs in dry season conditions and approximately 7.0 cfs during fall-season storms.

Water quality in the Arboretum Waterway is generally acknowledged to be poor in summer,predominantly because of nuisance algae growth. A study was conducted in 1990-1991 to investigateArboretum Waterway water quality problems and develop options for improving its condition (Conners andDarby 1991). The study indicated that water quality was periodically impaired by inputs of storm waterrunoff from the Campus storm water system and animal husbandry research areas, which resulted in lowlevels of DO and high levels of algae growth. Table 4.1-3 shows values for selected water qualityparameters in the Arboretum Waterway in comparison with conditions considered hypereutrophic (i.e.,exhibiting excessive biological productivity). The study also found that the Arboretum Waterway sedimentscontained high levels of metals such as cadmium, chromium, copper, lead, nickel, and zinc.

Historically, discharges to the Campus storm water system from evaporative cooling towersprovided a significant portion of flow in the Arboretum Waterway. Investigations associated with theCampus Pretreatment Program, described below under “Pretreatment Program Requirements and Status”found that cooling tower discharges contained elevated levels of some metals. Table 4.1-4 shows asummary of trace metals that have been detected in samples collected in storm water from the CentralCampus pumping pond discharge to the South Fork of Putah Creek. As shown in Table 4.1-4, four tracemetals were detected in Arboretum Waterway storm water: total chromium, copper, lead, and zinc, withcopper and lead having the highest values relative to other permitted discharges to the South Fork of PutahCreek.

WWTP Replacement Project Draft EIRUniversity of California, Davis October 1996

Table 4.1-2. Background Water Quality in Putah Creek Upstream of Campus Boundary

Sample DateParameter (units)

11/21/95 11/30/95 12/7/95Temperature (°C ) 14.0 11.5 14.0Dissolved oxygen (mg/L) 9.4 10.4 9.4Arsenic (µg/L) 2.2 3.3 1.0Beryllium (µg/L) - - - - 1.1Chromium, total (µg/L) 6.5 8.0 6.5Chromium, hexavalent (µg/L) - - - - - -Copper (µg/L) - - 1.2 1.4Metals (Sb, Cd, Pb, Hg, Ni, Se, Ag, Th, Zn) - - - - - -EPA 601: Purgeable Halocarbons - - - - - -EPA 602: Purgeable Aromatics - - - - - -EPA 603: Acrolein, Acrylonitrile - - - - - -EPA 604: Phenols - - - - - -EPA 608: Organochlorine Pesticides/PCB’s - - - - - -EPA 612: Chlorinated Hydrocarbons - - - - - -EPA 625: Semi Volatile Organic Compounds - - - - - -EPA 605: Benzidines - - - - - -EPA 611: Haloethers - - - - - -Tributyltin (µg/L) - - 0.009 - -

Notes: -- = not detectedmg/L = milligrams per literµg/L = micrograms per liter

Sb = antimonyCd = cadmiumPb = leadHg = mercuryNi = nickelSe = seleniumAg = silverTh = thalliumZn = zinc

Source: Data reports from ANLAB Analytical Laboratory, November-December 1995.


Table 4.1-3. Chemical and Nutrient Concentrations Used in the Classification of HypereutrophicLakes and a Comparison to Values from the Arboretum Waterway

Parameter (units)Hypereutrophic

ConditionsArboretum Waterway

Conditions

Nitrate + nitrite (mg/L N) > 1.5 0.40

Organic nitrogen (mg/L NH3 - N) > 1.2 2.6

Total phosphorus (mg/L PO43-) > 0.31 2.0

Change in alkalinity during the summer(mg/L CaCO3) > 50 66

Chlorophyll - a (µg/L) 100 - 150 122

Source: Connors and Darby 1991.

Table 4.1-4. Summary of Analytical Data and Pollutant Concentrations forPermitted and Storm Water Discharges

Analytical Data Summary

Pollutant Discharge Source Maximum(µg/L)

Minimum(µg/L)

Average(µg/L)

Median(µg/L)

SampleSize

n

PercentDetected

Chromium, total PCRFACStorm Water

4.0013.009.50

4.0013.004.40

4.0013.006.93

4.0013.006.90

113

100%100%100%

Chromium, hexavalent AC 18.00 18.00 18.00 18.00 1 100%

Copper PCRFACStorm Water

3.301.5014.00

3.301.504.70

3.301.508.63

3.301.507.20

113

100%100%100%

Lead AWCLACStorm Water

4.002.009.20

1.002.001.55

2.002.004.42

1.002.002.50

313

33%100%100%

Mercury AC 0.013 0.013 0.013 0.013 1 100%

Zinc ACStorm Water

2.0037.00

2.0017.00

2.0025.00

2.0021.00

13

100%100%

Chloroform AC 2.30 2.30 2.30 2.30 1 100%

Toluene AWCL 4.00 1.00 2.00 1.00 3 33%

Notes: PCRF = Putah Creek Research Facility.AC = Aquatic Center.

AWCL = USDA Aquatic Weed Control Laboratory.Storm Water = Central Campus storm water pumping pond.

Source: Jones & Stokes Associates compiled data presented in this table from sources listed in Table 3 of Appendix D.


Between February and April 1996, the discharges from 32 of the approximately 65 Campuscooling towers were routed to the WWTP. The cooling towers and their discharge characteristics arediscussed in greater detail below under “Metals and Organic Compounds in WWTP Effluent”. TheArboretum Waterway currently receives only drainage from overland runoff and the Campus storm watersystem.

Miscellaneous Storm Water Discharges. A California Department of Transportation(Caltrans) storm water detention basin for the highway interchange of I-80 and Highway 113 dischargesto the South Fork of Putah Creek at an outfall approximately 0.5 mile upstream of the WWTP. Reviewof the records for the detention facility for the past 10 years indicated an average annual pumping rate of0.013 mgd. The facility has three pumps with a combined maximum potential daily pumping capacity ofapproximately 17.3 mgd. (Scharosch pers. comm.)

In addition, storm water drains discharge to the South Fork of Putah Creek above and below theexisting WWTP outfall at various locations. Storm water from the Campus airport is discharged upstreamvia the Aquatic Center discharge, and three storm drains associated with the South Campus area arelocated in the vicinity of the existing WWTP outfall (Figure 4.1-2). The storm drains discharge primarilymiscellaneous landscape drainage in the summer.

Locations and Water Quality of Permitted Wastewater Discharges. UC Davis has severalpoint source (i.e., readily identified discharge source) discharges to Putah Creek that are permitted underthe National Pollutant Discharge Elimination System (NPDES). The NPDES permits are administered bythe Central Valley Regional Water Quality Control Board (CVRWQCB). NPDES permits place limitationson the quality of point source wastewater discharges to receiving waters. The regulatory requirements ofthe NPDES permit system are described in detail under “Regulatory Setting”.

The only permitted point source discharges along Putah Creek in the vicinity of the Campus areassociated with Campus facilities. The locations of the discharges in relation to the existing WWTP effluentoutfall are shown in Figure 4.1-2. These discharges are the Putah Creek Research Facility, the AquaticCenter, the USDA Aquatic Weed Control Laboratory, and the existing WWTP. A substantial amount ofwater quality information exists for the South Fork of Putah Creek and permitted discharges as a result ofvarious monitoring requirements for UC Davis operations. Water quality in this reach of the South Forkof Putah Creek is best described in relation to these larger discharges and their water quality. Table 4.1-4presents a summary of analytical data and pollutant concentrations for these permitted discharges. TheWWTP discharge is discussed below under “WWTP Effluent Water Quality and Other Characteristics”.

The Putah Creek Research Facility, an experimental fish hatchery, is allowed to discharge up to1.44 mgd of process wastewater to the South Fork of Putah Creek through an outfall approximately 3.0miles upstream of the existing WWTP outfall. The permit limits are shown in Table 4.1-5. The facilitydischarges an average of approximately 0.65 mgd. Maximum allowable concentrations have been set forbiochemical oxygen demand (BOD) and total suspended solids (TSS) in the effluent. The facility is requiredto monitor its effluent on a monthly basis for several conventional parameters (temperature, BOD, pH, TSS,and chlorine residual) and every other month for an acute toxicity bioassay. The facility collected one


sample for total chromium and copper analysis shown in Table 4.1-4, which were detected at low levels(University of California, Davis 1990). The facility has maintained a good record of compliance with itsNPDES permit limits (California Regional Water Quality Control Board 1995a).

The Aquatic Center is also an experimental fish hatchery. It is permitted with the Putah CreekResearch Facility according to limits shown in Table 4.1-5. The facility is also allowed to discharge up to1.44 mgd of process wastewater through an isolated evaporation pond and then to the South Fork of PutahCreek approximately 1.0 mile upstream of the WWTP outfall, and 0.014 mgd to the North Fork Cutoff,the dry historic channel of Putah Creek. The NPDES permit restricts the concentrations of BOD and TSSin the effluent. The hatchery generally discharges only a portion of the permitted amount (approximately0.61 mgd) and is required to monitor effluent water for conventional inorganic parameters (pH andconductivity/specific conductance). The facility has also maintained a good record of compliance with itsNPDES permit limits (University of California, Davis 1995b; California Regional Water Quality ControlBoard 1995a).

Another permitted discharger, the USDA Aquatic Weed Control Laboratory, contributes a minoramount of wastewater (0.075 mgd during the wet-weather period, 0.050 mgd during the dry-weatherperiod) approximately 2.0 miles upstream of the existing WWTP outfall. The facility operates accordingto the effluent limits shown in Table 4.1-6 and is required to monitor several conventional parameters (pH,temperature, TSS) in the effluent on a monthly basis and copper, several aquatic herbicides, and acutetoxicity twice per year. Quarterly monitoring is required for conventional parameters and chronic toxicitynear the discharge point.

UC Davis recently obtained an NPDES permit to discharge up to 0.23 mgd of treated groundwaterfrom the Campus landfill groundwater cleanup system to Putah Creek, although the discharge continues tobe treated at the WWTP. Table 4.1-7 shows the proposed permit discharge limits for the treatment systemthat will apply if or when discharged to the creek. The groundwater is being treated to remove chloroform,which is the principal pollutant of concern because it has exceeded the maximum contaminant level forprimary drinking water standards (University of California, Davis 1994). Because concentrations ofhexavalent chromium present in the discharge are above the limit allowed for discharge to the South Forkof Putah Creek, the discharge is currently being routed to the WWTP. However, the discharge may berouted directly to the South Fork of Putah Creek at a later date when this limit can be met.

WWTP Effluent Water Quality and Other Characteristics

The WWTP contributes a significant portion of the flow to the South Fork of Putah Creek duringdrier periods of the year. Therefore, characteristics of WWTP effluent discharges and water quality andthe influence of effluent water quality on the South Fork of Putah Creek are described in detail separatelyin this section.

Permit Conditions . The NPDES permit for the Campus WWTP effluent water quality limits(Permit No. CA0077895, CVRWQCB Order No. 92-040) was revised in 1992. The permit limits the


Table 4.1-5. NPDES Permit Limits for the Putah Creek Research Facility and Aquatic Center

Effluent Discharge Limitations

Constituents Units MonthlyAverage

WeeklyAverage

DailyMaximum

BOD, 5-day mg/Llbs/day

10240

15360

25600

Total suspended solids mg/Llbs/day

25600

40960

651,562

Settleable solids ml/L - - 0.1

Chlorine residual mg/L - - 0.02

pH (standard units): maintained between 6.5 and 8.5

Average dry weather flow (May through October): < 2.88 mgd

Whole effluent 96-hour bioassay: - > 70% minimum survival for any one test - > 90% median survival for any 3 or more consecutive tests

Dissolved oxygen: not < 1.0 mg/L for 16 hours in any 24-hour period in irrigation canals and ponds

Notes: ml/L = milliliters per literBOD = Biochemical oxygen demand, 5-day at 20° Clbs/d = pounds per daymgd = million gallons per day

Source: CVRWQCB; NPDES Permit No. CA0083348.


Table 4.1-6. NPDES Permit Limits for the USDA Aquatic Weed Control Laboratory

Effluent Discharge Limitations

Constituents UnitsMonthlyAverage

WeeklyAverage

MonthlyMedian

DailyMaximum

Total suspended solids mg/L 30 45 - 90

Copper µg/L - A - B

Fluoridone µg/L - - 0.1 0.2

Bensulfuron methyl µg/L - - 0.5 1.0

2,4-D µg/L - - 0.2 0.4

Glyphosate µg/L - - 2.0 4.0

Diquat µg/L - - 1.0 2.0

Trichlopyr µg/L - - 0.5 1.0


Average dry weather flow (May through October): < 0.05 mgd

Peak wet weather flow: < 0.075 mgd


Notes: A = e 0.8545H - 1.465, where H = ln {hardness (mg/L CaCO3)B = e 0.9422H - 1.464



Table 4.1-7. NPDES Permit Limits for the Landfill Groundwater Cleanup System

Effluent Discharge LimitationsConstituents Units

Monthly Average Daily Maximum

Total chromium (Cr) mg/L - 0.05

Hexavalent chromium (CrVI)

mg/L 0.010 0.015

Volatile organiccompounds 1

µg/L ND 2 2xND 3

Vinyl chloride µg/L - 0.13 4


Peak flow: < 0.23 mgd


Notes: 1 Volatile organic compounds per EPA Method 601 (Purgeable Halocarbons).2 ND = Nondetectable concentrations are below the minimum detection level of 0.5 µg/Lwith the exception of 2-chloroethyl vinyl ether (1.0 µg/L), 1,1-dichloroethane (0.2 µg/L),dichloromethane (1.0 µg/L).3 ND = Daily maximum set at two times the minimum detection level to allow for commonsampling and laboratory errors.4 Based on EPA’s recommended cancer potency factor as a water quality criteria; however,typical laboratory minimum detectable concentration is 0.50 µg/L.



concentrations of BOD and TSS in the effluent, which generally guides the management actions of theWWTP for permit compliance. The permit limits are shown in Table 4.1-8. The CVRWQCB under OrderNo. 92-040, Receiving Water Limitation No. 14, also requires UC Davis to develop a pretreatmentmonitoring program to establish “local limits” for nondomestic sources of untreated wastewater to preventWWTP upset or bypass. Nondomestic discharges of wastewater to the WWTP include Campuslaboratories and related facilities, cooling towers, and septic tanks. The pretreatment program is designedto identify nondomestic users, perform extensive monitoring for trace metals and inorganic and organiccompounds, and develop discharge limits for the sources of these (Krieger & Stewart 1995). Thepretreatment program and local limits are described in more detail below and in Appendix E. The nextreview of the NPDES permit conditions will be in 1997, at which time any necessary changes to the permitwill be identified.

In 1995, effluent was discharged from the existing WWTP at an average annual rate ofapproximately 1.56 mgd. During 1996, the average monthly flow was 1.66 mgd, which reflects the addedflow from connection of the cooling towers and the landfill treatment facility discharge. Historically, theWWTP was designed to meet effluent discharge limits for BOD and TSS concentrations of 30 milligramsper liter (mg/L) each at a permitted capacity of 4.16 mgd. The existing permit limits the monthly averageconcentrations of BOD and TSS to 20 mg/L from November 1 through April 30 and 10 mg/L from May1 through October 31 of each year. The daily maximum allowable concentrations for both BOD and TSSvalues are 25 mg/L in summer and 50 mg/L in winter. The existing permit conditions have effectively limitedthe capacity of the WWTP to approximately 2.0-2.5 mgd during dry weather. The WWTP is not allowedto meet its permit limits through the use of a dilution or mixing zone in the receiving stream and, therefore,compliance with the permit is based on effluent water quality, or “end-of-pipe conditions”. The NPDESpermit also requires UC Davis to perform chronic effluent toxicity testing using the three-species bioassayto ensure that the WWTP effluent does not cause instream toxicity. The NPDES permit has no currentlimits for trace metals or organic compounds and does not require UC Davis to conduct sediment toxicityor fish tissue monitoring.

Other permit limits for effluent quality include maximum daily limits during any time of the year forchlorine residual of less than 0.1 mg/L, total coliform bacteria counts of less than 500 MPN/100 ml (mostprobable number per 100 ml), and pH from 6.5 to 8.5. Chlorine is a disinfectant that is used as a biocidein the WWTP and in cooling tower water. The WWTP effluent is chlorinated for disinfection, thendechlorinated before it is discharged to the South Fork of Putah Creek. The permit also imposes numericaland narrative limits on the impacts of effluent discharges on the receiving water. The permit has numericallimits for temperature, DO, turbidity, and pH in the receiving water. The permit restricts the maximumincrease in turbidity to 10% over background levels, temperature to 2.8°C, and pH to 0.5 unit between thesamples collected from the South Fork of Putah Creek immediately upstream and downstream of theWWTP outfall. The DO in the receiving water is not allowed to be less than 5.0 mg/L. Narrative limits areplaced on parameters such as odor, color, presence of scums and slimes, and discharge of oil or grease.

Monitoring Programs and Water Quality Conditions in the South Fork of Putah Creek. Water quality is monitored directly above and approximately 250 feet below the WWTP outfall on aweekly, monthly, or quarterly basis, depending on the test, pursuant to the NPDES permit conditions for


Table 4.1-8. NPDES Permit Limits for WWTP Effluent

The discharge of an effluent in excess of the following limits is prohibited from 1 May through 31 October:

Constituent Units30-Day

Average7-Day

Average30-DayMedian

DailyMaximum

BOD1 mg/Llbs/day2

10347

15520

----

25868

Total suspended matter mg/Llbs/day2

10347

15520

----

25868

Settleable matter ml/L -- -- -- 0.1

Total coliform organisms MPN/100 ml -- 23 500

Chlorine residual mg/L -- -- -- 0.1

The discharge of an effluent in excess of the following limits is prohibited from 1 November through 30 April:

Constituent Units30-Day

Average7-Day

Average30-DayMedian

DailyMaximum

BOD1 mg/Llbs/day2

20694

301041

----

501736

Total suspended matter mg/Llbs/day2

20694

301041

----

501736

Settleable matter ml/L -- -- -- 0.1

Total coliform organisms MPN/100 ml -- -- 23 500

Chlorine residual mg/L -- -- -- 0.1

Notes: 1 5-day, 20 degree C, biochemical oxygen demand (BOD).2 Based upon a design treatment capacity of 4.2 mgd.

Additional limitations: n The discharge shall not have a pH less than 6.5 nor greater than 8.5. n The 30-day average daily dry weather discharge flow shall not exceed 4.2 million gallons. n The Discharger shall use the best practicable cost-effective control technique currently available to limit

mineralization to no more than a reasonable increment. n By-pass or overflow of untreated or partially treated waste is prohibited. n The discharge shall not cause the following conditions in Putah Creek: dissolved oxygen concentrations

to fall below 5.0 mg/L; visible oil, grease, scum, foam, floating or suspended matter; concentrations of anymaterials that are deleterious to human, animal, aquatic, or plant life; aesthetically undesirablediscoloration; fungus, slimes, or other objectionable growths; bottom deposits; an increase in turbidity bymore than 10% over background levels, alteration of the normal ambient pH by more than 0.5 unit, or anincrease the normal ambient temperature by more than 5 degrees F.

Source: California Regional Water Quality Control Board Central Valley Region Order No. 92-040, NPDES No.CA0077895, adopted on 28 February 1992.


the WWTP. The accumulation of data provides a substantial record with which to characterize waterquality conditions in the South Fork of Putah Creek below the WWTP outfall, the potential effects on waterquality, and some of the factors affecting the fate of pollutants discharged to the stream. Table 4.1-9 showsminimum, maximum, and average values for selected conventional water quality parameters in the SouthFork of Putah Creek from 1992 through June 1996.

The data indicate that the South Fork of Putah Creek exhibits elevated temperatures, low levels ofDO, and the presence of nuisance algae scums during the summer low-flow conditions (University ofCalifornia, Davis 1996a). The conditions are typical of the Central Valley, where summers are warm andlow-flow conditions persist. The most recent monitoring data from 1995 and 1996 indicate that the WWTPgenerally complied with receiving water permit conditions downstream of the outfall. DO values werealways in compliance with permit limits and temperature and pH values exceeded the limits onlyoccasionally. The pH values varied little throughout the year and have been indicative of the high mineralcontent and associated alkalinity of the South Fork of Putah Creek. In winter, turbidity was often high,presumably as a result of excessive amounts of suspended matter entering the stream channel upstream ofthe outfall. The effluent occasionally exceeds permit limits for turbidity during high flow conditions in thewinter and spring. Monitoring data from previous years indicated that the receiving water permit limits forDO were periodically exceeded, particularly in the summer when stream flow is minimal or absent.Temperature, pH, and turbidity values have also exceeded applicable permit limits in the past.

Historically, WWTP effluent discharges provided a majority of the flow in the South Fork of PutahCreek during seasonal periods of low flow. Therefore, the South Fork of Putah Creek water qualityprimarily reflected that of the effluent discharges. A recent court judgement regarding minimum instreamflow requirements, discussed above in “Surface Water Hydrology - Putah Creek”, may eventually providefor an increased minimum instream flow of 5 cfs in the South Fork of Putah Creek. If implemented, theseincreased minimum flow requirements for the South Fork of Putah Creek would have a beneficial effect onwater quality in the vicinity of the WWTP outfall.

Effluent Compliance Record. The WWTP has a good record of meeting NPDES limits forconventional parameters measured in the effluent (California Regional Water Quality Control Board 1995b). Prior to 1993, water quality monitoring of the WWTP effluent was conducted with samples collected ata constant rate irrespective of flow volume. The WWTP currently uses a flow-weighted water qualitysampling procedure to provide a more representative analysis of the effluent conditions. Samples arecollected on a daily, weekly, or monthly basis, depending on the parameter. A summary of monthlyminimum and maximum and average annual values from 1992 through June 1996 for selected conventionalparameters is shown in Table 4.1-10.

The most recent monitoring data (1995 and 1996) indicate that the WWTP has a good compliancerecord for BOD, TSS, chlorine residual, pH, and total coliform bacteria. The permit limit for chlorineresidual of 0.1 mg/L was exceeded once in June 1996. In addition, permit limits were exceeded once forthe monthly average TSS, twice for the 7-day average TSS, and once for the 7-day average BOD in 1996. The average 7-day TSS value was also exceeded once in 1995.

Table 4.1-9. South Fork of Putah Creek Downstream of the WWTP Outfall:Summary of Monthly Monitoring Results for Conventional Parameters, January 1992 - June 1996

1992 1993 1994 1995 1996Parameter(units) Min Max Mean Min Max Mean Min Max Mean Min Max Mean Min Max Mean

DO (mg/L) 5.0 11.2 8.5 4.4 12.4 8.4 0.1 11.0 5.5 3.7 9.8 6.4 5.9 11.0 8.2

pH (standard units) 6.8 8.2 7.7 7.3 8.6 8.0 5.8 9.0 7.5 6.2 8.6 7.9 6.7 7.8 7.4

Turbidity (NTU) 1.8 500 17.6 2.3 80 16.2 1.2 65 7.3 4.0 70 18.4 9.0 95 32

Temperature (°C) 11.0 28.0 19.0 3.0 25.0 15.5 7.0 24.0 17.3 9.0 26.0 16.7 9.0 28.0 15.9

Notes: Min = minimumMax = maximumDO = dissolved oxygen

mg/L = milligrams per literNTU = nephelometric turbidity unit

Source: University of California, Davis 1996.

Table 4.1-10. Campus WWTP Effluent: Summary of Monthly Monitoring Resultsfor Conventional Parameters, January 1992 - June 1996

1992 1993 1994 1995 1996Parameter(units) Min Max Mean Min Max Mean Min Max Mean Min Max Mean Min Max Mean

20 °C BOD (mg/L) 1 14 5.0 1 20 6.0 1 65 7.0 2 17 6.0 <3 18 8.3

TSS (mg/L) 1 24 5.0 0.5 14 6.0 0.5 131 5.5 1 26 8.0 <3 19 9.8

Specific conductance(µS/cm)

900 1,100 988 890 1,100 972 850 1,080 933 650 1,000 892 600 1,000 778

pH (standard units) 6.9 8.6 7.3 6.6 7.5 7.2 6.6 7.7 7.0 6.5 8.0 7.1 6.5 7.8 6.8

Total coliforms(MPN/100 ml)

<2 300 8.0 <2 240 4.8 <2 64 10.3 <2 23.0 2.0 <2 70 7.4

Chlorine residual (mg/L) 0 3.7 0.1 0 0.02 0 0 0 0 0 0 0 0 1.19 0.01

Daily Flow (mgd) 0.73 2.76 1.58 0.72 2.36 1.64 0.68 2.28 1.45 0.84 2.21 1.56 0.99 2.48 1.66

Notes:Min = minimumMax= maximumBOD = biochemical oxygen demandmg/L = milligrams per litermgd = million gallons per day

MPN/100 ml = most probable number per 100 millilitersTSS = total suspended solids

µS/cm = microsiemens per centimeter

Source: University of California, Davis 1996.


Monitoring data from 1992 indicated a number of exceedances for chlorine residual. In thereporting periods since 1993, the WWTP has exceeded its permit limit for chlorine residual only once. TheWWTP has a good compliance record for meeting permit limits for BOD in the effluent. The monthlyaverage BOD limit of 10 mg/L was exceeded in June 1994; the value of the exceedance was 19 mg/L. Theeffluent has not exceeded the monthly median or daily maximum limits for total coliform bacteria.

Chronic whole effluent toxicity tests on the WWTP effluent have generally been conducted on aquarterly basis for three organisms: fathead minnow (Pimephales promelas), water flea (Ceriodaphniadubia), and a green algae (Selenastrum capricornutum). Results of tests conducted on the water fleahave routinely exceeded threshold limits for reproduction in the organism (University of California, Davis1996a). Of 26 tests for effects of effluent on water flea reproduction from 1990 through the second quarterof 1996, 15 tests have exceeded threshold limits. In the 26 tests for survivability of the water flea, five testsexceeded threshold limits. The water flea is a very sensitive indicator organism and reduced reproductioncoupled with generally acceptable results for survival indicate the presence of relatively low-level toxicityin the effluent (Hall pers. comm.). During the same period, threshold criteria for fathead minnow survivaland growth were each exceeded two times. Criteria for growth of the green algae were also exceededtwice.

The source of the chronic toxicity threshold exceedances was not identified. However, the effluentused for the tests was also analyzed for conventional parameters, including pH, total alkalinity, hardness,nitrate, ammonia, and DO. For the period of 1991 through the second quarter of 1996, using the waterflea, on some test dates the average ammonia concentration in effluent that exceeded threshold toxicity limitswas 3.3 mg/L NH3-N. However, on other test dates an average ammonia concentration of 5.2 mg/L NH3-N did not cause threshold toxicity limits to be exceeded. Therefore, no apparent relationship between thetest results and ammonia concentrations was evident, indicating that ammonia may not be the cause of thetoxicity. There can be considerable variability in chronic toxicity test results, and test results have beenshown to be affected by the hardness or mineral content of the source water, particularly when the sourcewater is substantially different from the water used to culture the test organisms. Additionally, there iscurrently considerable debate regarding the reproducibility and reliable response levels of each chronictoxicity test (Hall pers. comm.).

Trace Metals and Organic Compounds in WWTP Effluent. This section describes availabledata for trace metals and organic compounds from samples of the WWTP effluent. Samples for a varietyof metals and organic compounds have been collected from the WWTP outfall in association withinvestigations conducted for the pretreatment program, the LEHR/SCDS site investigations, and recentmonitoring of the WWTP in 1996 conducted as a result of recent changes in discharges to the WWTP. These changes are discussed in detail below under “Recent Changes in Discharges to the WWTP”. Thereare currently no NPDES permit limits for trace metals or organic compounds in the WWTP effluent. However, water quality criteria undergo periodic review and revision, which could affect permit limits in thefuture. Potential future water quality criteria are discussed further under “Regulatory Setting” and arepresented in Table 4.1-15 later in this chapter under “Impacts and Mitigation Measures”.


Recent Changes in Discharges to the WWTP. Approximately 65 cooling towersprovide evaporative cooling for Campus facilities. Thirty-two of the cooling towers historically werepermitted through the NPDES system to discharge to the Arboretum Waterway. The other cooling towersdischarged to the sanitary sewer. Maximum discharges from the cooling towers in the summer to theArboretum Waterway were estimated at approximately 0.12 mgd. The water quality of these dischargeshas been a concern in the past because of the presence of a number of trace metals and the organiccompound tributyltin, a biocide, above discharge permit limitations. Data collected for the pretreatmentprogram from 1990 to 1995 indicated that cooling tower discharges had levels of arsenic, hexavalentchromium, copper, selenium, and tributyltin above discharge permit limits. Tests also showed high pH andchlorine residual values routinely exceeded discharge permit limits.As a result of connecting the coolingtower discharges to the WWTP, the previous NPDES permit was rescinded by RWQCB in June 1996. To evaluate the potential effects of this change on the WWTP, the Campus collected additional data in Juneand July of 1996 for trace metals and organic compounds to monitor for any changes in effluent quality,except for total and hexavalent chromium, which have been monitored on a nearly weekly basis sinceOctober 1995 (University of California, Davis 1996b). The Campus plans to continue collecting data fortrace metals and organic compounds in WWTP effluent to monitor the quality of the effluent.

The other change that occurred was that the discharge from the groundwater treatment facility atthe West Campus landfill was connected to the existing WWTP in October 1995. Since that time, UCDavis obtained an NPDES permit from the RWQCB for this facility to discharge to the South Fork ofPutah Creek and may route this discharge to the creek in the future.

Trace Metals. Many factors affect the toxicity of trace metals, including pH, waterhardness, and the amounts that are present in total and dissolved forms. Chromium is a metal of concernbecause it can exist in several chemical valence states and potential toxicity varies with the valence. Ingeneral, in waters with aerobic environmental conditions and moderate pH, most chromium present will bein the oxidized form as hexavalent chromium (Cr[VI]) (Faust and Aly 1981). In this form, chromium ismore toxic than under environmental conditions where oxygen is absent or very limited. The other commonvalence state is trivalent chromium (Cr[III]), which is considerably less toxic. Consequently, applicablewater quality criteria for Cr(VI) are lower than for Cr(III) in order to protect water quality and aquatic life. The applicable water quality criteria for hexavalent chromium are 15 µg/L for the maximum value and 10µg/L for the average value. The applicable criterion for total chromium (as Cr[III]) is the federal drinkingwater standard, which is a maximum of 50 µg/L. Therefore, the potential for conversion of total chromium(as Cr [III]) to hexavalent chromium in a permitted discharge may be of concern with respect to thesecriteria. However, in many waters, chromium can be present as both Cr(III) and Cr(VI). This indicates thatthe conversion of chromium is either incomplete or very slow, or that Cr(VI) is being reduced, or converted,to Cr(III). The rate of the conversion process is a very important consideration and in most cases appearsto be more important than the pH or level of oxidation. Bartlett (1991) states that “The barriers to Cr(III)oxidation in soils and waters are kinetic or rate driven. Most of this form of Cr(III) found in polluted soilsand waters is insoluble and immobile”. For example, in one study Cr(III) was found to be the dominantform in several natural waters surveyed, which contradicts thermodynamic predictions but agrees with datapresented in findings of other studies (Kaczynski and Kleber 1993). Therefore, because the rate ofoxidation is slow or non-existent in most situations, it is unlikely that a significant portion of the Cr(III) in


WWTP effluent would be oxidized to Cr(VI). It is also possible that some Cr(VI) would be reduced orconverted to Cr(III) by other chemical processes (Kaczynski and Kleber 1993).

Values for total chromium are indicative of the amount of Cr(III) that could potentially be convertedto Cr(VI) under ideal or worst-case environmental conditions. Recent and historic monitoring data areshown in Table 4.1-11 to reflect the effluent concentrations before and after the cooling towers wereconnected to the WWTP. The most recent data, which were collected from April-July 1996, reflecteffluent quality since the recent connection of the cooling towers to the WWTP and generally indicate thateffluent discharges of trace metals are low. Total chromium, hexavalent chromium, and mercuryconcentrations were lower than historic data. Hexavalent chromium was not detected in any samples abovethe detection limit of 10 µg/L. Total chromium values were below both the applicable drinking waterstandard and the water quality criteria for hexavalent chromium. In addition, the most recent monitoringreport (1995) for the LEHR/SCDS site (Pacific Northwest National Laboratory 1996) did not detecthexavalent chromium, and total chromium was low in relation to both criteria. Based on these data and thediscussion above, the potential conversion of total chromium to hexavalent chromium, in excess ofapplicable criteria, in the South Fork of Putah Creek due to the WWTP discharge would be low to non-existent.

Mercury was not detected; however, the detection limit for mercury was higher than the applicablewater quality criterion for aquatic life protection. Recent data for trace metals also indicated that copperconcentrations were higher than historic data. Other metals detected at low levels in the recent samplingof WWTP effluents include cadmium, lead, selenium, and silver.

The WWTP effluent historically has contained relatively low levels of most trace metals (PacificNorthwest National Laboratory 1996, Dames and Moore 1995), as indicated in Table 4.1-11 for datacollected from 1992-1995. Monitoring conducted for the pretreatment program during one week in 1993indicated that the WWTP influent had elevated levels of copper, mercury, hexavalent chromium, and silver,and these metals were therefore included as a high priority in that program. Under historic conditions, themajority of samples analyzed for hexavalent chromium had concentrations lower than the typical detectionlimit (<10 µg/L) used for the various investigations. Total chromium, when detected, was generally belowwater quality criteria for both total and hexavalent chromium. In general, copper was often detected in theWWTP effluent. Mercury was detected under historic conditions in 37% of the samples, with bothmaximum and average values being higher than the recent data for existing conditions. Arsenic and zincwere detected in a majority of the samples at relatively low levels.

Organic Compounds. The recent data for existing conditions generally indicate thateffluent discharges of most organic compounds were relatively low. Notable decreases from historic valueswere observed for methylene chloride, 1,2 dichlorobenzene, and gamma-BHC. In particular, 1,2dichlorobenzene and gamma-BHC were not detected during the recent sampling. The average tributyltinvalue decreased from the single historic value; however, the maximum value detected was higher. Valuesfor bromodichloromethane, chloroform, and bis(2-ethylhexyl)phthalate increased relative to historic data. Other organic compounds detected at relatively low levels during recent sampling include carbon


tetrachloride and dibromochloromethane. Refer to Appendices D and E for a discussion of Campus actionsthat are being taken to address these potential water quality issues.

Historical effluent monitoring data collected for LEHR/SCDS investigations indicated that, ingeneral, the effluent contained relatively low levels of organic compounds (Pacific Northwest NationalLaboratory 1996, Dames and Moore 1995). The organic compounds methylene chloride and bis(2-ethylhexyl)phthalate were frequently detected at relatively high concentrations. Gamma-BHC was detectedin about 54% of the samples collected, and tributyltin was detected at a relatively high level. However, thedata for tributyltin was based on only one sample (Table 4.1-11).

Sludge Drying Ponds . The WWTP currently dewaters the liquid biosolids (i.e., treated sewagesludge) that are generated by anaerobic digesters in a series of unlined sludge drying ponds. The ponds areon the west side of the Campus just south of the California Regional Primate Research Center (CRPRC),approximately 2.5 miles west of the WWTP. The dried sludge is then stockpiled adjacent to the ponds forapproximately 1-2 years. The sludge is tested yearly for compliance with 40 CFR, Part 503 regulations. Biosolids regulations are described in greater detail below under “Regulatory Setting”. At a minimum, thebiosolids currently meet at least Class B regulatory criteria for pathogen reduction, which is suitable forcertain restricted uses. The uses for which biosolids from the existing WWTP are suitable include landfillingand land application in areas that have restricted access, such as agricultural fields. Ultimate biosolidsdisposal is determined by the annual test results, and the Campus has generally not disposed of stockpiledbiosolids, except for small amounts in restricted areas on Campus.

The sludge drying ponds have been monitored to further evaluate elevated levels of total dissolvedsolids (TDS) and nitrate that were present in nearby shallow groundwater monitoring wells. Table 4.1-12shows values for metals analyzed in 1993 for the biosolids produced at the WWTP. The data indicate thatthe biosolids had low levels of metals in relation to regulatory criteria and would meet the most stringentcriteria for metals associated with biosolids reuse. The Campus landfill currently cannot accept WWTPbiosolids because of limits for manganese (Nolte and Associates 1995a). However, disposal of biosolidsmay be considered at another landfill site. The biosolids could be used for land application at restrictedaccess sites. Further treatment of the biosolids to meet Class A standards for pathogen reduction may alsobe considered to allow unrestricted use.

Laboratory for Energy-Related Health Research and South Campus Disposal Site Area

The LEHR/SCDS area is approximately one mile south of the existing WWTP, south of theproposed WWTP site, and adjacent to the South Fork of Putah Creek. The LEHR/SCDS area has beenthe focus of several investigations for soil and groundwater contamination that occurred as a result ofhistorical practices. The site is currently in the process of a Remedial Investigation and Feasibility Studyin which specific problems that have been identified previously are being studied and remedial action plansfor their cleanup are being prepared. Detailed descriptions of the facilities and research activities conductedat the LEHR/SCDS area were presented in the 1994 LRDP EIR (University of California, Davis 1994). Chapter 7 of this EIR updates the information in the 1994 LRDP EIR. This section summarizes informationpresented in Chapter 7.

Table 4.1-11. WWTP Effluent: Summary of Analytical Data and Pollutant Concentrations


Pollutant Data PeriodMaximum

(µg/L)

Minimum(µg/L)

Average(µg/L)

Median(µg/L)

SampleSize

n

PercentDetected

Arsenic a Historic Conditions (1992-1995)b Existing Conditions (June-July 1996)

5.607.9

2.003.20

3.945.07

4.504.85

196

47%100%

Cadmium Historic Conditions (1992-1995)Existing Conditions (June-July 1996) 0.95

NOT0.05

DETECTED0.28 0.11 6 83%

Chromium, total Historic Conditions (1992-1995)Existing Conditions (April-July 1996)

25.009.70

2.104.00

6.425.21

5.005.00

1920

42%30%

Chromium, hexavalent Historic Conditions (1992-1995)Existing Conditions (April-July 1996)

20.00 5.00NOT

6.42DETECTED

5.00 3319

12%0%

Copper Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

15.0026.00

4.9515.00

6.9722.00

5.0024.00

136

38%100%

Lead Historic Conditions (1992-1995)Existing Conditions (June-July 1996) 1.40

NOT0.50

DETECTED1.02 1.20 6 67%

Mercury Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

0.63 0.10NOT

0.16DETECTED

0.10 196

37%0%

Selenium Historic Conditions (1992-1995)Existing Conditions (June-July 1996) 1.70

NOT0.50

DETECTED0.83 0.50 6 33%

Silver Historic Conditions (1992-1995)Existing Conditions (June-July 1996) 1.60

NOT0.50

DETECTED0.90 0.80 6 50%

Zinc Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

60.0078.00

10.0016.00

30.2141.00

30.0037.00

196

89%100%

1,2 Dichlorobenzene Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

3.00 0.50NOT

1.37DETECTED

0.63 186

22%0%

Table 4.1-11. WWTP Effluent: Summary of Analytical Data and Pollutant Concentrations


Pollutant Data PeriodMaximum

(µg/L)

Minimum(µg/L)

Average(µg/L)

Median(µg/L)

SampleSize

n

PercentDetected

Bromodichloromethane Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

5.4018.00

0.502.00

1.3112.67

1.0513.50

196

37%100%

Carbon tetrachloride Historic Conditions (1992-1995)Existing Conditions (June-July 1996) 1.60

NOT0.25

DETECTED0.78 0.79 6 67%

Chloroform Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

16.0046.00

2.204.50

7.3430.58

5.9034.00

196

95%100%

Dibromochloromethane Historic Conditions (1992-1995)Existing Conditions (June-July 1996) 8.60

NOT0.52

DETECTED5.55 5.90 6 100%

Methylene chloride Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

25.004.00

0.500.50

6.062.15

5.102.10

196

79%67%

Toluene Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

3.004.10

0.500.25

1.400.89

0.680.25

196

26%17%

Bis(2-ethylhexyl)phthalate

Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

30.00150.00

2.007.50

6.0044.42

5.0019.75

196

47%50%

Gamma-BHC Historic Conditions (1992-1995)Existing Conditions (June-July 1996)

0.07 0.00NOT

0.02DETECTED

0.01 136

54%0%

Tributyltin Historic Conditions (1992-1995Existing Conditions (June-July 1996)

0.050.140

0.050.026

0.050.056

0.050.042

16

100%100%

Notes: a Source: Jones & Stokes Associates compiled data presented in this table from sources listed in Table 3 of Appendix D.b Source: University of California, Davis 1996b.

Table 4.1-12. Regulatory Criteria (EPA Part 503) for Trace Metal Content of Biosolids and Test Results for Existing WWTP Biosolids for 1993 - 1996

Concentration (Dry Weight, mg/kg)a December 1993 b June-July 1995 c August-September 1995 d July 1996Pollutant

Mean Max Min Mean Max Min Mean Max Min Mean Max Min

PollutantConcentrationLimits for EQ e

Biosolids f

Values MeetEPA 503

EQ BiosolidsStandards?

Antimony ND ND ND 0.76 3.8 ND ND ND ND 0.80 3.2 ND - -

Arsenic 8.7 8.7 ND 8.0 14 ND 22 32 ND 10.5 24 ND 41 Yes

Barium 1,233 3,100 282 83 140 32 119 160 7.6 98 200 9.3 - -

Beryllium 1.48 2.67 0.82 0.21 0.34 0.01 0.34 0.94 ND ND ND ND - -

Cadmium 7.4 8.3 6.5 1.7 3.5 0.85 4.0 4.9 2.8 3.2 6.8 ND 39 Yes

Chromium, total 209 217 200 52 92 25 89 110 75 73 150 5.5 1,200 Yes

Chromium, hexavalent ND ND ND ND ND ND ND ND ND ND ND ND - -

Cobalt 15.0 19.7 12.0 6.7 12.0 2.4 11.6 16.0 ND 5.5 14.0 ND - -

Copper 744 817 615 130 240 64 216 300 140 200 400 14 1,500 Yes

Lead 89 92 85 19 34 11 35 50 25 36 74 ND 300 Yes

Mercury 8.1 8.7 7.3 2.5 6.3 0.49 4.7 6.5 3.3 2.8 6.8 0.10 17 Yes

Molybdenum ND ND ND 2.5 6.6 ND 9.4 14 4.5 3.5 14 ND 75 c Yes

Nickel 84 108 52 39 80 12 86 100 34 39 89 2.8 420 Yes

Selenium 10.3 13.3 6.7 1.8 3.7 0.78 2.6 5.1 0.97 1.8 4.6 ND 36 Yes

Silver 142 180 68 2.4 3.5 1.6 9.2 15 3.2 23.6 76 2.7 - -

Thallium ND ND ND 5.0 15 ND 23 29 14 16 58 ND - -

Vanadium 100 117 85 28 49 15 42 60 2.3 32 64 1.8 - -

Zinc 959 1,083 795 234 410 150 461 1,100 220 571 1,200 30 2,800 Yes

Notes: mg/kg = milligrams per kilogram.a Samples taken from existing sludge drying beds 2, 3, and 4 on December 17, 1993.b Samples taken from existing sludge drying beds 1, 2, 3, and 4 on June 29, 1995 and bed 5 on July 5, 1995.c Samples taken from existing sludge drying beds 1, 2, 3, and 4 between August 24, 1995 and September 26, 1995.d Samples taken from existing sludge drying beds 1,2, and 3 on July 24, 1996.e EQ = exceptional quality standards for trace metal concentrations.f Source: A Plain Guide English Guide to the EPA Part 503 Biosolids Rule (U.S. Environmental Protection Agency 1994).g Represents the ceiling concentration limit for all biosolids applied to land. The limits for molybdenum were deleted from the Part 503 rule pending EPA review.ND = not detected.-- = No limit established.

Source: University of California, Davis 1996b.


Surface drainage from the LEHR/SCDS area is generally conveyed south towards the southernboundary of the area that is formed by the South Fork of Putah Creek levee. A large drainage canal islocated along the east side of the area and drains south to the levee, where it flows to the South Fork ofPutah Creek. Drainage from the parking area in the southwest corner of the LEHR/SCDS area is conveyedto a small storm drain and pumped to a ditch west of Old Davis Road that drains to the South Fork ofPutah Creek. In addition, one small cooling tower that services the SCDS area is connected directly to thesanitary sewer system. The proposed WWTP site is generally level and surface drainage is generally to theeast, where it is conveyed to the South Fork of Putah Creek via the drainage canal.

Historical Research Activities and Land Use Practices. The former LEHR facility was usedby the U.S. Department of Energy (DOE) from 1960 to 1989 to conduct research related to the effectsof bone-seeking radionuclides on animals. Materials and wastes generated from the research activities wereburied in a number of trenches and pits located along the southern property boundary. The site is beinginvestigated by DOE in conjunction with UC Davis to determine the extent of contamination and developremedial actions needed to clean up the site. The soils and groundwater at the site are known to containa variety of organic compounds, metals, and radionuclides. In addition, two former Campus landfill units(Landfill Disposal Units #1 and #2) located on the property are under investigation. Chemical disposaltrenches are presumed to be a source of shallow groundwater contamination primarily associated with theorganic compound chloroform (University of California, Davis 1994). The extent of soil and groundwatercontamination that may be associated with the LEHR/SCDS area is still under investigation (PacificNorthwest National Laboratory 1996).

The old WWTP for UC Davis is located east of the LEHR site. The former Campus LandfillDisposal Unit #3 is located along the eastern edge of the property adjacent to the drainage canal. The extentof soil and groundwater contamination that may be associated with the old WWTP and landfill facilities arestill under investigation. Detailed descriptions of groundwater quality investigations and results are presentedbelow under “Groundwater Quality”.

A number of remedial actions have already been taken, including the removal of liquid and solidwastes containing radioactive or hazardous materials. The Campus is currently considering preventivemeasures to reduce the potential for interception and transport of pollutants in the drainage canal along theeastern edge of the site in the vicinity of Landfill Disposal Unit #3 to the South Fork of Putah Creek. Thesemeasures could include surface water barriers and diversion and lining of the drainage canal in this vicinitywith concrete, or remediation using capping or removal of landfill wastes (Oatman pers. comm.). Furtherinvestigations of soil and groundwater contamination are under way to develop remedial action plans. DOEand UC Davis are in negotiations concerning the allocation of responsibilities for the various investigativeand remedial actions that will be required to clean up contaminated sites.

Water Quality Characteristics. Water quality monitoring has been conducted in the South Forkof Putah Creek as part of the LEHR/SCDS area investigations since late 1990. Results from samplescollected in the South Fork of Putah Creek above and below the WWTP outfall are indicative of the waterquality conditions for parameters not monitored by other programs.


The most recent data, which were collected in 1995, indicated low levels of antimony, arsenic, totalchromium, hexavalent chromium, copper, lead, selenium, and zinc (Pacific Northwest National Laboratory1996). Ammonia levels in the South Fork of Putah Creek were also low in samples from 1995. However,data collected during 1992-1994 indicated that ammonia was present in the South Fork of Putah Creekin high enough levels to be potentially toxic to fish under certain background conditions of pH andtemperature in the stream (California Regional Water Quality Control Board 1995b, Dames and Moore1995). Historic data also indicated that maximum contaminant levels (MCLs) for either the primary orsecondary drinking water standards were periodically exceeded for iron, nitrate, antimony, total chromium,nickel, selenium, and thallium. Water quality criteria for aquatic life protection were exceeded at least oncefor hexavalent chromium, lead, copper, and selenium.

Analyses of organic compounds in South Fork of Putah Creek samples from 1992-1994 detectedthe following pesticides at least once: DDD/DDE (i.e., DDT decay products), aldrin, alpha-BHC, beta-BHC, gamma-BHC, dieldrin, endosulfan-I, endosulfan-II, endrin aldehyde, and heptachlor (CaliforniaRegional Water Quality Control Board 1995b). The lands surrounding the Campus are used primarily foragriculture, and it is possible that the pesticides were from historic uses upstream of the WWTP (Universityof California, Davis 1994). Phthalate compounds, common contaminants associated with plasticware usedin routine laboratory analyses, were detected frequently in samples. Methylene chloride above the drinkingwater standard had been detected previously but was not detected in 1995. The volatile organic compound(VOC) acetone was also commonly detected. VOCs including dichloromethane, chloroform,bromodichloromethane, and dibromochloromethane, were detected; these VOCs can be produced duringthe chlorination of water. DOE is continuing to monitor these VOCs to determine if the detections continueand are of potential concern (Oatman pers. comm.). No PCB compounds were detected in 1995.

Drinking water standards have been established for the radiochemical compounds gross-alpha,gross-beta, radium-226, strontium-90, and tritium. The radionuclides strontium-90, carbon-14, and tritiumwere detected in several samples but were below drinking water quality standards. Radionuclides arediscussed in greater detail in Chapter 4.3, “Hazardous Materials and Public Safety”.

In the fall of 1994 and winter of 1995, samples were collected from two of the storm drains thatdischarge to the South Fork of Putah Creek. The storm water system at the LEHR/SCDS area is notregulated under current law. The samples were analyzed for a suite of inorganic, organic, metal, andradionuclide compounds. No radionuclides were detected in the storm water samples. The samples hadrelatively high levels of antimony, lead, and zinc that approached or exceeded one or more of the drinkingwater standards or ambient water quality criteria for toxicity to aquatic life (California Regional WaterQuality Control Board 1995b). Organic compounds have not been detected above regulatory criteria. Theonly organic compound detected was acetone, a compound that has no associated federal or state waterquality criteria.


Groundwater Quality

Background Conditions

The source of domestic drinking water for the Campus and neighboring agricultural and residentialareas is groundwater from deep aquifers. Therefore, maintaining and protecting groundwater quality is animportant consideration for Campus development. The deep aquifers are relatively isolated by their greatdepth from influences of activities that occur on the land surface. The quality of groundwater underlying theCampus is generally acceptable for domestic uses and has historically met federal drinking water standardsfor concentrations of regulated chemicals on a routine basis (University of California, Davis 1994). However, groundwater samples from the City of Davis wells have exceeded the federal and state drinkingwater standards for selenium of 10 micrograms per liter (µg/L). The groundwater is generally acceptablefor designated beneficial agricultural and industrial uses.

The quality of shallow groundwater is largely dependent on the quality of surface water thatpercolates into the ground and subsequent chemical interactions with the soils and bedrock. Factors thatare important to the susceptibility of shallow groundwater to contamination include the type of soil andwater-bearing materials, permeability of the soil to surface water infiltration, location of pollutant sources,and depth to the aquifer. Potential sources of contamination of shallow groundwater include agriculturalapplication of fertilizers and pesticides, hazardous material spills from industrial and commercial processes,leachate from hazardous waste storage facilities or solid waste landfills, septic tank leachate, infiltration ofcontaminated urban storm water runoff, and seepage of wastes from concentrated livestock operations.

Local Aquifers

Groundwater in the vicinity of the Campus is generally considered to have a high mineral content,with calcium, magnesium, and sulfate constituting the majority of the ions (University of California, Davis1994). The groundwater has relatively high levels of TDS and salinity. Nitrate levels in many private wellssampled in the area frequently exceeded drinking water standards (U.S. Department of Health and HumanServices 1995). Hexavalent chromium was detected in all of the private wells sampled in another studyconducted to evaluate potential sources of this pollutant (Dames & Moore 1990). The study indicated thathexavalent chromium could be derived naturally from geochemical processes occurring in the sediments.Eleven wells were sampled by the Campus Environmental Health and Safety Department (EH&S) in 1990; results of the chemical analyses performed are shown in Table 4.1-13.

The CVRWQCB revised the NPDES permit limits for the WWTP during the most recent permitrenewal (1992) for biosolids handling and associated environmental monitoring to include groundwatermonitoring. Groundwater quality samples are now collected quarterly for several conventional parameters(pH, specific conductance, and chemical oxygen demand [COD]) from several wells near the biosolidsstorage ponds. Monitoring data to date indicate that groundwater under the sludge drying ponds containedelevated levels of nitrates and inorganic salts that contribute to salinity (University of California, Davis 1994).


These constituents are not considered hazardous. Nitrate has been detected in both downgradient andupgradient monitoring wells, and monitoring results indicate that it decreases from upgradient todowngradient. The specific source of the nitrate in the wells is not certain, but the concentration range isrelatively wide. A common source of nitrate in groundwater includes fertilizer applied to crops (nitrate isa primary constituent of agricultural fertilizer).

UC Davis is collecting samples quarterly for a groundwater quality monitoring program near theCampus landfill west of Highway 113. The landfill was historically the disposal site for various wastesgenerated on the Campus and included chemical burn trenches. The groundwater sample data haveindicated elevated levels of VOCs downgradient of the landfill (University of California, Davis 1994). Chloroform, a compound in widespread use for various manufacturing processes, is the principal volatilecompound of concern in the groundwater samples. Other detected volatile compounds include 1,1-dichloroethane, tetrachloroethane, trichloroethane, trichlorofluoromethane, and 1,1,1-trichloroethane. Nitrates have been detected at levels that approach drinking water standards in both above- and below-gradient well samples. Only hexavalent chromium has been detected at levels that exceed the drinkingwater standard for total chromium of 50 µg/L (University of California, Davis 1995c). The averagehexavalent chromium concentration found in monitoring well samples was 48 µg/L, and the maximum valuedetected was 67 µg/L. Average hexavalent chromium concentrations of 10.3 µg/L and 27.0 µg/L have beenreported in domestic supply wells and utility wells, respectively, in Davis (University of California, Davis1995c). Soil and groundwater investigations are ongoing, and UC Davis is currently discharging the treatedgroundwater from the landfill to the WWTP.

Laboratory for Energy-Related Health Research and South Campus Disposal Site Area

Groundwater in the vicinity of the LEHR/SCDS area occurs in two principal hydrostratigraphicunits (HSUs). HSU-1 extends to approximately 80 feet below ground surface (bgs); this unit is composedof fine grain materials and has low transmissivity of water supply production capability. Groundwater levelsvary during the year from 28 to 48 feet bgs. HSU-2 is composed of coarse materials, has considerablygreater transmissivity than HSU-1, and extends from approximately 80 to 135 feet bgs. A thick clay layerforms a barrier or aquiclude between HSU-2 and groundwater zones below.

Monitoring conducted for the LEHR/SCDS area since 1990 has indicated that groundwater hadelevated levels of total and hexavalent chromium, chloroform, selenium, pesticides, nitrate, and tritium inconcentrations that exceed the primary drinking water standards (Regional Water Quality Control Board1995a). The most recent monitoring results, which were collected in 1995, indicated that nitrate, sulfate,TDS, total and hexavalent chromium, selenium, chloroform, and three VOCs (1,1-dichloroethane, 1,1-dichloroethene, and 1,2-dichloroethane) exceeded drinking water standards in one or more monitoringwells. Antimony, arsenic, barium, and several pesticides were above background levels in some wells butbelow applicable drinking water criteria. One well had detections of several pesticides, including dieldrin,endrin, alpha-BHC, and gamma-BHC in both 1994 and 1995. The radionuclides tritium and carbon-14were consistently found in several wells. However, data collected during this period indicated that the levelof tritium was below the drinking water standard; there is no drinking water standard for carbon-14. With


Table 4.1-13. Summary of Inorganic Constituentsin Groundwater of the UC Davis Campus Area

Parameter (units) Minimum Maximum

Turbidity (NTU) < 0.2 < 0.5

Iron (mg/L) < 0.019 0.160

Total dissolved solids (mg/L) 300 990

pH 0.414 1.37

Nitrate (mg/L NO3 - N) 7.8 8.3

Arsenic (µg/L) < 4 < 4

Cadmium (µg/L) < 1 4

Chromium (µg/L) < 10 40

Lead (µg/L) < 1 10

Copper (µg/L) < 20 170

Zinc (µg/L) < 10 60

Notes: mg/L = milligrams per liter.NTU = nephelometric turbidity unit.µg/L = micrograms per liter.

Source: Conners and Darby 1991.


the exception of one well sample, gross-beta and gross-beta radiation levels were below their respectivedrinking water standards. Positive values were detected at least once in 1995 for several radionuclides,including plutonium-241, americium-241, and strontium-90; however, these radionuclides were generallyonly slightly above background levels. No PCB compounds were detected in the 1995 samples.

Migration of pollutants has occurred in a direction coinciding with the groundwater gradient, whichis generally to the east and north of the LEHR/SCDS area. There is no indication that migration is occurringto the south. Some wells have shown high levels of TDS, sulfate, selenium, and VOCs, such as chloroform,that may be a result of waste disposal in the landfills and waste trenches. The source of chloroform andtritium is thought to be the waste trenches near Landfill Disposal Unit #2. A plume with elevated levels ofchloroform extends north and east beyond the LEHR/SCDS area. The plume extends further in HSU-2due to the increased transmissivity of groundwater. The plume of tritium is much smaller than the chloroformplume, and detections indicate that the tritium is migrating downward from HSU-1 to HSU-2. Nitrate levelsare elevated with respect to the primary drinking water standard throughout the area and in HSU-1 inparticular. Landfill Disposal Unit #2 may be a source of locally elevated nitrate concentrations, and a plumehas been monitored that coincides with the chloroform plume. Nitrate concentrations decline to backgroundlevels in wells located near the east LEHR/SCDS area. Chromium is found in two distinct regions west andnorth of Landfill Disposal Unit #2 and the chloroform plume and are indicative of separate contaminationsources. The chromium has not migrated as far as the chloroform and is generally present only in HSU-1. Monitoring is continuing at the site as part of the Remedial Investigation and Feasibility Study beingconducted at the site.

Samples from farm wells near the LEHR/SCDS area have shown a wide variation in the distributionof elevated nitrate concentrations and indicate that the nitrates probably came from localized sources, suchas farm fertilizers, concentrated areas of animal waste discharge, and septic tanks. Concentrations ofhexavalent chromium have ranged from 20 µg/L to 160 µg/L. Potential sources include natural geochemicalmobilization of sedimentary deposits or contamination from a regional waste source, such as incineratorwaste or industrial effluents. Surface water in Putah Creek can recharge the aquifer and potentiallytransport pollutants to the groundwater; however, the rate of transport is low in relation to that of othersources of groundwater recharge (Pacific Northwest National Laboratory 1996, University of California,Davis 1994).

UC Davis has submitted a plan to regulatory agencies to pump and treat contaminated groundwaterat the LEHR/SCDS area. Potential remedial actions were investigated, and it was determined thatgroundwater extraction and treatment would be the most feasible strategy. Further studies will beconducted and the system will then be designed. The treatment system is anticipated to be constructed andoperational by mid-1997. These activities are discussed in detail in Chapter 7.


REGULATORY SETTING

Water Quality Regulations

Central Valley Regional Water Quality Control Board/Sacramento River Basin Water QualityControl Plan

The CVRWQCB has primary authority for implementing SWRCB policy and ensuring that waterquality and designated beneficial uses of water resources are protected from potential adverse impacts ofdevelopment in the project area. Water quality objectives and numerical water quality criteria areestablished in the CVRWQCB water quality control plan (Basin Plan) to protect the established beneficialuses of surface water and groundwater (California Regional Water Quality Control Board 1995d). TheCVRWQCB implements the basin plan by imposing waste discharge requirements that are triggered byestablished regulatory controls, such as the NPDES permit process.

Putah Creek has designated beneficial uses from Lake Berryessa to its terminus at the Yolo Bypassthat include municipal, industrial, and agricultural water supply, contact and noncontact recreation, warmand cold freshwater habitat, and wildlife habitat. Numerical surface water quality objectives of the BasinPlan that are applicable to the South Fork of Putah Creek and the proposed WWTP replacement projectare included in the NPDES permit limits. Narrative water quality objectives applicable to Putah Creekinclude criteria for toxicity, biostimulatory substances (i.e., nutrients such as nitrogen and phosphorus), taste,and odor. The Basin Plan generally requires that a stream with a designated beneficial use for municipal anddomestic supply must meet applicable primary MCLs, as established in the state and federal drinking waterstandards; these are also discussed further below. Water quality objectives for groundwater also requirethat municipal and domestic supply sources of groundwater meet the MCLs established in state and federaldrinking water standards.


NPDES Permit System

Wastewater Treatment Plant Discharges. Wastewater treatment plants that discharge toreceiving waters are regulated through the NPDES permitting process as mandated under the Clean WaterAct (CWA) (Code of Federal Regulations, Title 40 [40 CFR]). EPA has designated the RWQCB as thestate agency in charge of issuing NPDES permits. The NPDES permit system is divided into separateprograms and regulations for point source discharges, such as industrial facilities and wastewater treatmentplants, urban storm water runoff from municipalities, and storm water runoff from general construction andindustrial activities. The NPDES permit process for wastewater treatment plants typically involves theimposition of concentration criteria on the effluent and receiving water body for various chemical, physical,and biological parameters, such as flow, temperature, BOD, DO, total coliform bacteria, TSS, totalsettleable matter, turbidity, residual chlorine, ammonia, or other compounds of specific concern for a givenreceiving water. The permit can also specify limits on the total quantity or mass of a pollutant allowablein the discharge over a defined period of time. In some situations, the wastewater treatment plant can begranted an allowance for dilution of the effluent in a mixing zone, a defined section of the receiving waterwith a downstream boundary where imposed water quality limits must be met. If no dilution allowance isgranted in the permit, the wastewater treatment plant must meet criteria in the effluent. For compliancepurposes, the NPDES permit requires the discharger to perform water quality monitoring for compoundswith established permit limits and submit monitoring reports.

Storm Water Discharges. The RWQCB also grants and implements NPDES permits for stormwater discharges that are associated with specific construction and industrial activities. An NPDES GeneralConstruction Activity Permit is required for projects that disturb more than 5 acres of land. The permitrequires the development of an approved erosion control plan, a storm water pollution prevention plan(SWPPP) that describes temporary and permanent best management practices (BMPs) that must beemployed to control and minimize runoff of pollutants, and self-monitoring and reporting of water qualityduring a period of construction.

UC Davis currently has an NPDES General Industrial Storm Water Permit for the existing WWTPand several other facilities that requires the implementation of pollution prevention measures. The permitrequires elimination of illicit storm water discharges from the WWTP, development of an SWPPP similarto that needed for the General Construction Activity Permit, and monitoring of the quality of storm waterdischarges.

Water Quality Criteria and Standards for Toxic Pollutants

In the future, the CVRWQCB will be required to incorporate additional limits for toxic pollutantsin the NPDES permit for discharge of WWTP effluent to the South Fork of Putah Creek. These limitswould most likely be based on the following four potential sources of criteria and standards:

n the Inland Surface Waters Plan (ISWP),


n the National Toxics Rule (NTR),

n ambient water quality criteria for the protection of human health and aquatic life from variousEPA publications, and

n federal and state drinking water standards.

States are allowed by EPA to adopt the recommended criteria or develop site-specific criteriaprovided that the decision process is justified on a scientific basis of beneficial use protection. Theestablished guideline is to select the water quality standard based on criteria needed to protect all beneficialuses of the receiving water body. Selected criteria must protect the most sensitive beneficial use designatedfor the water body identified in the Basin Plan. The criteria also must implement the water quality objectivesof the Basin Plan. Given the beneficial uses designated by the CVRWQCB in the Basin Plan for PutahCreek, the CVRWQCB will be required to select criteria that are protective of municipal and domesticsupply, agricultural and industrial supply, and aquatic life when establishing and renewing the NPDES permitfor the Campus WWTP (Marshack pers. comm.).

Inland Surface Waters Plan. The ISWP established narrative ambient water quality objectivesand numerical criteria for approximately 110 metal and organic compounds discharged to inland surfacewaters. However, in 1994 the ISWP was the subject of a lawsuit and eventually was overturned. The planis currently under review and being prepared for readoption in 1997. The proposed WWTP dischargewould most likely be subject to the provisions of the ISWP at that time.

National Toxics Rule and U.S. Environmental Protection Agency Ambient Water QualityCriteria. EPA promulgated the NTR in December 1992 and established water quality criteria forapproximately 129 pollutants. EPA currently has the authority under the NTR, the regulation on which theISWP was patterned, to enforce numerical water quality criteria in California for 40 of these pollutants(California Regional Water Quality Control Board 1995c). Guidelines for the protection of aquatic life areestablished by EPA in publications such as the “Gold Book” (U.S. Environmental Protection Agency 1986)and other publications (California Regional Water Quality Control Board 1995c); these guidelines form thethird potential source of criteria for future WWTP regulation. Federal and state drinking water standardsform the final source of potential regulatory criteria for the WWTP.

The NTR, which is based largely on EPA ambient water quality criteria, and the ISWP are focusedon the protection of human health and aquatic organisms from risks associated with exposure to specificcompounds. Ambient water quality criteria contained in the NTR and original ISWP were established byEPA to protect human health and to prevent toxic effects in freshwater and marine aquatic organisms(California Regional Water Quality Control Board 1995c). Human health criteria were established for theNTR and are updated through a rigorous and complex process of analysis of potential toxic effects ofexposure to each chemical compound. All proposed criteria must undergo a public process of review,comment, and adoption by EPA or the state. States must determine ambient criteria for the two primaryroutes of human exposure, the ingestion of drinking water and fish.

The EPA procedures for selecting aquatic life criteria involve characterization of the risk ofexposure to individual chemicals. Research data regarding the susceptibility of biological organisms to toxic


effects are compiled and analyzed through an extensive risk analysis process. Sufficient data on the 48-hourand 96-hour exposure tests for lethal or immobilizing effects are required to establish an acute criterion. Data on the ratio of acute to chronic toxicity concentrations are required to establish a chronic criterionbased on acute test results. Chronic criteria are based directly on 28-day exposure tests that measuresurvival, growth, reproduction, or bioconcentration. Acute and chronic criteria for some pollutants (e.g.,ammonia, metals) are related to the value of other parameters such as pH, temperature, and hardness.

The characterization of risks to human health from exposure of individual chemicals is developedfrom epidemiological research data and stored in EPA’s electronic database, the Integrated RiskInformation System (IRIS). Risk factors are based on a lifetime exposure basis of 70 years. Uncertaintyfactors are then applied to account for such aspects as variability among individuals, extrapolation from testorganisms to humans, data on other than long-term exposures, and weaknesses or gaps in the data. Anycriterion for a carcinogen is based on at least three considerations: potency, exposure, and riskcharacterization. States may make their own judgments on the these factors given reasonable scientificjustification. The criteria for carcinogens are developed for various levels of incremental cancer risk (e.g.,10-5, 10-6, or 10-7). Criteria for noncarcinogens are developed from the “no adverse effect level” or “lowestobserved adverse effect level” that are identified from chronic or subchronic human or animal exposurestudies.

Federal and State Drinking Water Standards . Drinking water standards, established by theCalifornia Department of Health Services (DHS) under Title 22, Division 4, Chapter 15 - Domestic WaterQuality and Monitoring, are applicable to groundwater and surface water in the Campus area. EPAdevelops similar standards under the federal Safe Drinking Water Act. Both sets of laws contain maximumcontaminant levels (MCLs) that are based on a one-in-a-million (10-6) incremental risk of cancer fromingestion of carcinogenic compounds and threshold toxicity levels for noncarcinogens. The MCLs are alsobased on technological and economic factors of the feasibility of achieving and monitoring for the pollutantsin a drinking water supply. Secondary MCLs are established for welfare considerations such as taste andodor control and laundry staining. The MCLs apply to the quality of the water after it has entered adistribution system and do not apply to the quality of the untreated source water. The standards apply tothe source water only when specifically established in the basin plan by the RWQCB.

Pretreatment Program Requirements and Status

The following is a summary of regulations applicable to the pretreatment program and the status ofthe program. A complete discussion of the pretreatment program requirements and status is presented inAppendix E.

EPA created the National Pretreatment Program and first issued pretreatment regulations inNovember 1973. Following CWA amendments, the regulations were revised in June 1978 and again inJanuary 1981. The purpose of the National Pretreatment Program is to regulate the discharge of toxicpollutants or unusually large amounts of conventional pollutants (e.g., BOD and TSS) to municipal sanitarysewers and the associated wastewater treatment plants. Toxic pollutants can include a large variety of


potential compounds but generally refer to heavy metals, VOCs, pesticides, and other chlorinated organiccompounds. The goal is to protect receiving water quality and the environment from the effects of thesedischarges because of their potential to “pass through” or receive only partial or no treatment by thewastewater treatment plant.

The Campus WWTP receives wastewater from a variety of sources, including academic buildings,operations and maintenance buildings, food service areas, agricultural facilities, a dairy, the cooling towers,septic tank wastes, and numerous types of laboratories. On March 3, 1992, the CVRWQCB amendedand updated the NPDES permit for the WWTP to require UC Davis to develop a pretreatment programto prevent WWTP upset or bypass from nondomestic wastewater discharges similar to those outlined in40 CFR Part 403. The new limitation in the revised NPDES permit requires that the program meet thefollowing objectives:

n identify pollutants that could cause upset or bypass (pollutants of concern),n develop discharge limitations for nondomestic discharges (local limits),n identify nondomestic discharge sources, andn develop a nondomestic monitoring program to enforce local limits.

These four objectives form the basis for the Campus WWTP pretreatment program activities. TheCampus has initiated pretreatment program actions to meet the four objectives listed above, with the initialfocus on the first three objectives.

Identification of Pollutants of Concern and Development of Local Limits. The identificationof pollutants of concern included a review of data and information on potential nondomestic dischargesources, water sources, and various phases of WWTP operation. Campus cooling towers and septic tanksystems were also included in this evaluation. Pollutants of concern were identified based on their knownor suspected presence using historic sampling data and EPA guidance. Based on a review of literature,discussions with UC Davis staff, and observations during inspections of Campus facilities, common usesand sources for most of these pollutants were also identified.

A list of pollutants of concern was compiled and used as the basis for the development of locallimits. The list was reviewed, and each pollutant was screened to determine whether it would be bestmanaged by treatment processes, it was already subject to overriding regulations, or there were no otherapplicable standards or guidelines for that pollutant. The proposed approach taken by the Campus wasto create local limits for selected pollutants of concern. Local limits include both narrative and numericlimits. Narrative limits are general statements of prohibitions or restrictions of a particular discharge, whilenumeric local limits are maximum allowable concentrations that are calculated for each pollutant of concernthat a facility discharge to the sewer cannot exceed. Numeric local limits are calculated from the mostlimiting criteria or standard that could upset the WWTP or pass through the WWTP in the effluent. Thecriteria and standards used for the local limit calculations included federal drinking water standards, EPAfreshwater aquatic toxicity criteria, the National Toxics Rule for California, and federal and state sludgedisposal regulations. These local limits specify the allowable flow and concentration for each pollutant of


concern that can be discharged to the WWTP and are particularly applicable to planned additional futuredischarge sources approved in the 1994 LRDP. Local limits are presented in Table E-2 of Appendix E.

Campus cooling tower discharges have historically contained seven pollutants of concern: arsenic,total and hexavalent chromium, copper, lead, selenium, and zinc. Some of the cooling towers havedischarged to the WWTP but, until recently, a substantial portion of the flow and loading from the coolingtower discharges went to the Arboretum Waterway. Between February and April 1996, discharges fromthese cooling towers were routed to the WWTP via the sanitary sewer.

The development process described above for the local limits considered septic tank waste loadingand current and future loading from all the cooling towers to the WWTP. The additional flow and loadingfrom the cooling towers was considered in the final local limits calculations using recent discharge data. Theanalysis indicated that there was very little change in the allowable remaining flow and loading for theseseven pollutants of concern due to the connection of the remaining cooling towers to the WWTP. Theexisting WWTP is expected to effectively treat this additional discharge because the additional pollutantloading from these cooling towers was already considered in the local limits calculation for the pretreatmentprogram and these limits will be met by the WWTP.

Data obtained on the WWTP effluent to document its quality since connection of the additionalcooling towers were described above in Table 4.1-11. The source control program for the cooling towerswill continue to be implemented as part of the overall pretreatment program for these pollutants of concernand to verify that concentrations of these pollutants are being reduced.

Implementation of the Pretreatment Program. The regulatory agency with jurisdiction overthe implementation and enforcement of the Campus pretreatment program is the CVRWQCB, withoversight from EPA. The Campus established three priority levels for pollutants of concern to address inthe implementation of the program. Five pollutants were identified as having a priority one status: copper,silver, mercury, methylene chloride, and diesel fuel. These are the pollutants on which the Campus isfocusing its pretreatment program efforts to identify specific sources and reduce or eliminate discharges tothe sanitary sewer. Other pollutants of greatest concern have been detected in Campus wastewater andwere assigned priority two or three because they exceeded local limits but have not repeatedly exceededany applicable standards (Table E-3 in Appendix E). These pollutants are proposed to be monitoredquarterly so that trends can be identified and it can be determined whether a higher priority status iswarranted.

The Campus has proposed several steps or key actions to ensure that local limits are met and thepretreatment program is fully implemented. The key actions being taken to implement the Campuspretreatment program and enforce local limits are:

n education,n routine and special monitoring,n responding to exceedances of local limits and repeat violations, andn follow-up monitoring.


Implementation of the Campus pretreatment program is shared by the WWTP staff, EH&S, andFacilities Services. Routine and special monitoring programs form the basis for the implementation of thepretreatment program and for meeting local limits. Routine monitoring includes quarterly collection andanalysis of WWTP influent, effluent, and collection system samples, and review of these results. Specialmonitoring involves facility inspection, sample collection on an as-needed basis, laboratory analysis, andreview of data. General sources for special monitoring and data review include those listed above forroutine monitoring and septic tank waste samples, rinse water from chemical waste storage containers,cooling tower blowdown discharges, and air scrubber discharges. Special monitoring is performed on anas-needed basis.

EH&S and Facilities Services have joint responsibility for local limit enforcement. FacilitiesServices is responsible for the sewer collection system and the WWTP and monitors discharges, collectssamples, and maintains records of the system. EH&S is responsible for management of the Campushazardous waste program, which addresses proper storage and disposal of most of the same chemicalsregulated through the pretreatment program. EH&S and Facilities Services collaborate to identify andeliminate discharges of pollutants in exceedance of local limits and review plans and drawings showingproposed facilities that discharge nondomestic wastes to the sewer. In addition, a waste minimizationcoordinator has been hired to assist the pretreatment program to reduce hazardous wastes and ensure theirproper disposal.

Title 22 Water Reclamation Criteria

DHS has primary responsibility for protecting public health and implementing provisions of Title22, Division 4, Chapter 3 of the California Code of Regulations. Title 22 provisions were developed toprotect human health from undo exposure to pathogens from projects involving water reclamation and reuseof waters. The DHS criteria include numerical limitations and requirements affecting water application(irrigation, landscaping, recreational impoundments); monitoring and analysis; and engineering design,operation, maintenance, and reliability of facilities. Requirements imposed under Title 22 are incorporatedinto NPDES permits administered by the CVRWQCB. For discharges to recreational impoundments suchas Putah Creek with the potential for body contact recreation, future NPDES permit limits would likelyrequire that allowable total coliform bacteria counts in the WWTP effluent not exceed a 7-day median valueof 2.2 MPN/100 ml or a daily maximum of 23 MPN/100 ml. These criteria and their applicability to publichealth and safety are discussed in more detail in Chapter 4.3, “Hazardous Materials and Public Safety”.

State Water Resources Control Board Thermal Plan

The State of California has adopted the Water Quality Control Plan for Control ofTemperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of Californiaor “Thermal Plan”. Objective 5A of the Thermal Plan prohibits: (1) a waste discharge that exceeds thenatural receiving water temperature by more than 20°F; and (2) a waste discharge that causes more than


a 1°F rise in more than 25% of the receiving water cross section at the discharge location. Temperaturelimits contained in the existing NPDES permit for the Campus WWTP already reflect the provisions of theThermal Plan.

Biosolids Regulations

The disposal of biosolids is regulated through a number of federal, state, and local regulations. Forfurther information regarding the regulations, existing and proposed biosolids treatment methods for theCampus WWTP, and regulatory compliance procedures for handling biosolids, refer to Attachment B ofthe Revised Initial Study, which is included in Appendix A of this EIR. Federal regulations for sewagesludge disposal under 40 CFR Part 503 are implemented by the CVRWQCB through limits in the wastedischarge requirements for the NPDES permit. The state also bases the disposal limits on guidelines forland spreading of biosolids provided by DHS (Department of Health Services 1983). The federalregulations are intended to promote beneficial use of biosolids while protecting public health and theenvironment and apply to biosolids that will be used for land application, surface disposal and storage, orincineration. Disposal of biosolids in landfills is still regulated by 40 CFR Part 258, which requires chemicaltests to determine the suitability of the material for disposal at a given landfill. The Integrated WasteManagement Board (IWMB) has developed draft regulations for composting biosolids that require aseparate self-implementing permit under Title 14, Division 7, Chapter 5 of the California Code ofRegulations.

The federal regulations are self-implementing in that they define standards, monitoring and reporting,and other operation and maintenance requirements that are enforceable without permits. The level ofpathogen and vector attraction reduction and trace metal concentrations determines the class of biosolidsproduced, and the associated allowable uses of those biosolids. Surface disposal and storage are dedicateduses of biosolids or domestic septage that can exceed the application rates (e.g., less restrictive) prescribedfor land application uses.

There are two general classes of biosolids under 40 CFR Part 503, Class A and Class B. Avariety of alternative treatment technologies is allowed for the treatment of biosolids to meet Class A andClass B requirements. In order to meet Class A standards for pathogen reduction, the biosolids mustundergo extended treatment, such as composting or heat treatment, to kill pathogens and allow for generallyunrestricted use. The state requires a wastewater treatment plant to obtain an IWMB permit whencomposting more than 10,000 cubic yards of material as a marketable Class A product. Class B biosolidsundergo treatment to reduce, but not totally eliminate, pathogens to allow for restricted use. Biosolids mustalso meet vector attraction reduction objectives to minimize the transport of diseases by pests such asrodents and insects. Indicators such as volatile solids reduction, specific oxygen uptake rate, and pH-timerelationships are monitored to determine when the biosolids have met vector attraction reduction standards.

Only Class A biosolids are allowed for land application uses that may involve immediate humanexposure to the product. Class A biosolids can be distributed for uses such as soil and garden amendmentsfor nurseries, ballfields, golf courses, and homeowners. Class B biosolids are restricted to certain land


application methods that limit access and human exposure to the site. Biosolids are further characterizedby the concentration of metals in the final treated product to be used. Biosolids that meet Class A standardsfor pathogen and vector attraction reduction and have low trace metal concentrations are termed“exceptional quality” biosolids and their use is virtually unrestricted. Land application is restricted for bothcumulative and annual application rates for both Class A or Class B biosolids that exceed trace metalconcentration thresholds termed “pollutant concentration levels”.

Chemical characteristics of biosolids generated at the existing WWTP indicate that the materialmeets at least Class B standards for pathogen reduction and exceptional quality for metals (Table 4.1-12). The existing biosolids treatment process was described in detail above under “Sludge Drying Ponds”.

WWTP Mechanical Reliability and Performance

The following reliability and performance specifications would apply to the proposed WWTP; theproposed WWTP would be designed to at least Class II reliability criteria.

Wastewater Treatment Plant Reliability Specifications

The reliability of a secondary wastewater treatment plant is a measure of the ability of a componentor system to perform its intended function without failure. Secondary wastewater treatment plants aredesigned to be highly reliable so that effluent quality requirements are met consistently under a variety ofconditions. These conditions include normal routine operation, scheduled maintenance or modification ofmajor pieces of equipment, emergency repairs, equipment failures, power outages, and wastewatertreatment plant upgrades. EPA has developed standards for reliability in the design of wastewater treatmentplants. The guidelines, “Design Criteria for Mechanical, Electrical and Fluid Systems and ComponentReliability” (1974), establish reliability criteria for three classes of wastewater treatment plants, as describedbelow:

n Class I. Wastewater treatment plants that discharge into navigable waters that could bepermanently or unacceptably damaged by effluent that was degraded in quality for only a fewhours. Examples of Reliability Class I works might be those discharging near drinking waterreservoirs, into shellfish waters, or in close proximity to areas used for water contact sports.

n Class II. Wastewater treatment plants that discharge into navigable waters that would not bepermanently or unacceptably damaged by short-term effluent quality degradations, but couldbe damaged by continued (on the order of several days) effluent quality degradation. Anexample of a Reliability Class II works might be one that discharges into recreational waters.

n Class III. Wastewater treatment plants not otherwise classified as Reliability Class I or ClassII.

In general, secondary wastewater treatment plants have specific protective features incorporatedinto their design to ensure that the systems perform reliably according to the criteria. The following


specifications are common design features of wastewater treatment plants developed to provide reliableservice:

n Flood protection. Located outside the 100-year floodplain.

n New equipment. All equipment is new and designed for long-term, heavy-duty, industrial usein the severe environment of a wastewater treatment plant. All equipment maintainable,repairable, and replaceable without causing permit violations.

n Redundancy. Standby equipment installed so that the wastewater treatment plant remains infunctional service should a piece of equipment fail or need to be taken out of service for anyreason. If a piece of equipment fails unexpectedly, controls automatically start the standby unitin its place.

n Process structures and tanks. Process structures, tanks, and piping designed to pass thepeak flow rate of the facility without overflowing or submerging equipment. Redundancydesigned into wastewater treatment plant structures and tanks.

n Septic tank waste processing. Processing provided for septic tank pumping operations. Oxidation ditch technology can receive large loads of concentrated wastes without adverselyaffecting the secondary treatment process, which ensures optimum performance.

n Wastewater treatment plant control and instrumentation. Operates automatically so thatchanges in wastewater flow or strength can be compensated for without degradation of effluentquality. Manual overrides provided on automatic controls where failure of the automaticcontrol would result in a permit violation. Instruments vital to wastewater treatment plantoperation and permit compliance provided with installed backup units.

n Alarms . Comprehensive alarm system that alerts operators to all equipment malfunctions,rising water levels, power outages, and intrusions. Alarm system monitored 24 hours per day.

n Electrical system. Two independent sources of power, including utility power and fuel-powered electric generator. Generator of sufficient size to operate all equipment and systemsvital to permit compliance. The transfer of power from the utility to the generator would beautomatic. Motor control centers (MCC) powered from two separate power feeders so thatthe loss of one feeder would not shut down the MCC.

Wastewater Treatment Plant Performance Specifications

The performance of a secondary wastewater treatment plant refers to the ability of the combinationof treatment processes to achieve a specified level of pollutant reduction in the influent stream of untreatedwastewater. Secondary wastewater treatment plants are designed to provide treatment components andsystems that produce effluent with quality characteristics acceptable to the regulatory agencies. As


discussed previously, the existing wastewater treatment plant effluent quality requirements apply principallyto conventional pollutants, such as BOD, TSS, temperature, and total coliform organisms.

The secondary treatment systems have proven capability to reduce the conventional pollutants tothe levels typically prescribed by regulatory agencies. The activated sludge process (e.g., oxidation ditchand clarifiers) has been used extensively throughout the world for BOD, TSS, and ammonia removal formore than 50 years. The oxidation ditch and clarifiers for the proposed WWTP would produce an effluentwith less than 10 mg/L each of BOD and TSS and less than 1 mg/L of ammonia. Sand filters are capableof further reducing BOD and TSS to levels below 5 mg/L.

The ultraviolet light (UV) disinfection process has a successful record of removing total coliformorganisms and other pathogens to the levels typical of effluent quality requirements (< 2.2 MPN/100 ml). Although relatively new in the United States, the use of UV radiation for disinfection is spreading rapidly. There are currently over 1,200 installations in the United States and thousands more in Canada andEurope. UV radiation is recognized by DHS as a reliable method of disinfecting wastewater for dischargeto streams used for body-contact recreation (i.e., unrestricted use).

Toxic pollutants such as trace metals and organic compounds are removed from wastewater by theactivated sludge process occurring in the oxidation ditch. The mechanisms for removal includebiodegradation, adsorption, volatilization, and chemical complexation. Research has shown the activatedsludge process to be superior to other municipal wastewater treatment processes for the removal of toxicorganics and heavy metals. Several features of the oxidation ditch enhance the activated sludge processfor removal of these compounds. These features include long aeration time (14 hours), long solids retentiontime (22 days), and the ability of operators to adjust the solids retention time over a relatively wide range. Two research programs conducted by EPA (Hannah et al. 1986, Petrasek et al. 1983) have found thatactivated sludge systems are capable of an 82% reduction in chromium, 82% removal of copper, and 79%-87% removal of bis(2-ethylhexyl)phthalate.

IMPACTS AND MITIGATION MEASURES

Standards of Significance

As stated in the 1994 LRDP EIR, an impact is considered significant if the project would:

n result in substantial changes in absorption rates, drainage patterns, or the rate and amount ofsurface runoff, which cause existing drainage capacity to be exceeded;

n substantially interfere with groundwater recharge; or

n substantially degrade surface and/or groundwater quality due to increases in sediments, erosion,and contaminants generated by construction and/or operation of the project.


Because of the specific nature of the proposed project, the following additional significance criteriahave been identified. An impact is considered significant if the proposed project would result in exceedanceof:

n water quality objectives contained in the CVRWQCB Basin Plan for surface waters andgroundwater; or

n NTR limits, EPA water quality criteria, and federal or state drinking water standards that couldbe used as potential future NPDES permit waste discharge requirements.

Impacts associated with microbial contaminants are addressed in Chapter 4.3, “HazardousMaterials and Public Safety”.

Project Impacts and Mitigation Measures


4.1-1 Campus growth accommodated by the proposed WWTP would result in an increase in theamount of water discharged to the South Fork of Putah Creek. This impact is consideredbeneficial.

The capacity of the proposed WWTP would be slightly higher than the capacity of the existingWWTP. The average annual discharge from the existing WWTP was 1.56 mgd (2.4 cfs) in 1993-1995and ranged from 1.2 mgd to 1.9 mgd (1.8-3.0 cfs). The average annual daily flow is expected to graduallyincrease to 2.5 mgd (3.9 cfs) in 2005 as the Campus population grows. The monthly average dry-seasondesign flow rate would be 2.7 mgd (4.2 cfs). The estimated average discharge rate from the proposedWWTP upon start up in 1999 would be 1.9 mgd (2.9 cfs).

Daily variations in wastewater discharge reflect variations in water demand and would not changeas a proportion of monthly average flow. For example, minimum daily discharge during 1994-1995 was59%-79% of mean monthly discharge, and maximum daily discharge was 117%-150% of mean monthlydischarge. This relative variability would not change.

Increased flows from the WWTP to the South Fork of Putah Creek are considered beneficial forthe following reasons:

n an increase in base flow generally creates an increase in available aquatic habitat,

n the additional flow would provide a buffer against unintended brief decreases in flow below theminimum required flows resulting from low- or no-flow situations as a result of the existingSolano Project release schedule or irregular operation of upstream water supply systems, and


n the quality of the effluent would likely be better than that of the existing WWTP because ofmore consistent and reliable treatment (see discussion of impacts under “Surface WaterQuality” below).

Mitigation Measure

4.1-1 No mitigation is required.

4.1-2 New impervious surfaces associated with the proposed WWTP would increase surfacerunoff, potentially exceeding the capacity of drainage facilities and resulting in localizedflooding. This impact is considered less than significant.

The impervious area at the proposed WWTP would consist of ponds, treatment processes andassociated structures, and solids storage basins (SSBs). Rain falling on these areas would be containedwithin the wastewater treatment system and would not contribute to storm water runoff from the site. Also,some rainfall would infiltrate in pervious areas of the WWTP that would have landscaping. The buildings,parking lots, and some structures would generate runoff, however.

The 1994 LRDP EIR stated that new impervious surfaces associated with development allowedunder the 1994 LRDP would increase surface runoff and could exceed existing drainage capacity and resultin localized flooding. This was identified as a significant impact and the 1994 LRDP EIR identified thefollowing mitigation measure to reduce this impact to a less-than-significant level.

4.8-2(a) Prior to approval of final project design, the Campus shall prepare adetailed drainage study to evaluate each specific development projectunder the 1994 LRDP to determine if project runoff would exceed thecapacity of the existing Campus storm drainage system.

4.8-2(b) If it is determined that existing drainage capacity would be exceeded, aspart of final project design the Campus shall design and implementnecessary and feasible improvements to minimize the occurrence oflocalized flooding. Such improvements could include, but would not belimited to the following:

(i) The expansion or modification of the existing storm drainage system. Site runoff could be controlled by upgrading the existing facilities, suchas the expansion, or installation of additional storm drain lines, orpumps.

(ii) Single-project detention or retention basins. Single-project peaksurface runoff flows could be limited in several ways, including smallon-site detention basins, rooftop ponding, temporary flooding of


parking areas, streets and gutters, landscaping designed to temporarilyretain water, and gravel beds designed to collect and retain runoff.

(iii) Multi-project storm water detention or retention basins.

In compliance with Mitigation Measure 4.8-2(a), a site-specific drainage study was completed byNolte and Associates (1996) to determine whether runoff from the project would exceed the capacity ofthe existing South Campus storm drainage system. The study indicated that runoff from the proposedWWTP would be 5.3 cfs during a 10-year storm event, which is the normal design standard for drainagefacilities of this type. The runoff from the proposed WWTP would require almost the entire capacity of theexisting 24-inch drainage pipeline (6.3 cfs) that crosses the site from west to east. Because the pipeline alsoconveys runoff from Campus facilities northwest of the SPRR tracks, the capacity of the pipeline would beexceeded during the design storm event.

Nolte and Associates (1996) calculated that a pipeline diameter of 30-36 inches would be requiredto convey the additional runoff from the proposed WWTP and that the existing capacity of the north-southdrainage canal from the end of this pipe and along the east side of the SCDS to the South Fork of PutahCreek is adequate to convey the increased flows. Construction of the WWTP would require relocationof the storm water drain pipe to an alignment along the northern edge of the proposed WWTP site. Alarger pipe would be installed when the drain is relocated. On rare occasions when very large flood eventsoccur (e.g., a 100-year flood), runoff from the surrounding area, including the proposed WWTP site, doesnot flow by gravity into the creek. During these conditions, the water level in the creek is higher than thewater level in the north-south drainage canal and a manually operated gate valve prevents creek water fromflowing into the drainage canal. There have been no observations or reports of localized flooding whenmajor storm events have occurred in the past, and there appears to be sufficient capacity in the drainagecanal to accommodate area runoff until the water level in the creek subsides and the gate opens (Markelpers comm.). The proposed WWTP would contribute only a very small additional amount of runoff to thenorth-south drainage canal, relative to the total contribution from the tributary area. Therefore, the verysmall amount of additional runoff from the proposed WWTP site would not substantially reduce the capacityof the north-south drainage canal during very large flood events. Thus, upon completion of the proposedWWTP, the South Campus drainage system would be capable of conveying the additional runoff from theproposed WWTP.

Mitigation Measure

4.1-2 No additional mitigation is required.

4.1-3 Increased effluent discharge and runoff from impervious surfaces at the proposed WWTPcould increase flood flows in the South Fork of Putah Creek. This impact is consideredless than significant.

The drainage study for the proposed WWTP (Nolte & Associates 1996) calculated the runoff ratefrom the proposed WWTP site for a 10-year rainfall event but not for a 100-year event. Rainfall intensity


for a 100-year event near Davis is approximately 50% greater than the intensity for a 10-year event(California Department of Water Resources 1976). Because additional infiltration losses for a 100-yearstorm are negligible, the 100-year runoff rate from the proposed WWTP site is approximately 10-15 cfs. The 100-year flood flow in the South Fork of Putah Creek is approximately 30,000 cfs, and inflows of lessthan about 100 cfs are not considered a significant problem (Cowan pers. comm.). The increase in effluentdischarge up to the maximum of 5.8 cfs (3.8 mgd) would have little or no effect on these combined flows. Therefore, this impact is considered less than significant.

Mitigation Measure



4.1-4 Relocation of the WWTP could result in minor changes in the location of groundwaterrecharge. This impact is considered less than significant.

There would be several changes in the location and timing of groundwater recharge as a result ofthe project, and many of the changes would offset each other. During the dry season, there would be adecrease in deep percolation of applied irrigation water at the proposed WWTP site, but there would bean increase in deep percolation at the existing WWTP site, which would be planted in grass followingdemolition. If the existing WWTP was not demolished, the amount of percolation would decrease slightly. The increase in discharge of treated wastewater to the South Fork of Putah Creek would also result inincreased recharge from the creek because of a slight increase in stage and wetted channel area that wouldresult from the increase in flow. Because the low-flow channel is largely ponded with steep banksdownstream of the discharge point, the increase in stage and wetted area would be very small. Estimatesof each of these changes in recharge are probably not accurate enough to reliably indicate whether therewould be a net decrease in groundwater recharge. It is clear, however, that the principal effect of theproject would be to shift the location of recharge rather than the total amount of recharge during the dryseason. Because all the locations mentioned overlie the same large groundwater basin and the amounts ofrecharge are small relative to the overall basin water budget, the change in location of recharge during thedry season would not appreciably affect local groundwater levels.

In the wet season, there would be similar compensating changes in groundwater recharge. Theincrease in impervious ground cover at the proposed WWTP site (approximately 6 acres) would be largelyoffset by the decrease in impervious ground cover that would result from demolition of the existing WWTP. If the existing WWTP is not demolished, there could be a minor decrease in the amount of groundwaterrecharge. Rainfall runoff from the proposed WWTP site would have a brief opportunity to infiltrate as itflowed down the drainage canal along the east side of the LEHR/SCDS area. The additional runoffcaptured from the impervious areas at the WWTP site would be discharged to the South Fork of PutahCreek following treatment, where it would have additional opportunity to infiltrate.


The effect of the proposed project on groundwater recharge would be less than significant. The1994 LRDP EIR stated that new impervious surfaces associated with development allowed under the 1994LRDP could reduce the potential for groundwater recharge. This was identified as a significant impact andthe following mitigation measure was identified.

4.8-3 The Campus shall incorporate where feasible as part of project design thefollowing measures, or equally effective measures, to maximize percolationand infiltration of precipitation into the underlying groundwater aquifers:

(a) the use of pervious paving material; or(b) preservation and utilization of natural drainage areas.

Application of this LRDP mitigation measure would further reduce the already less-than-significant effectsof the proposed WWTP project.

Mitigation Measure



4.1-5 Continued discharge of treated effluent to the South Fork of Putah Creek could result inpotential water quality degradation because of increased discharges of BOD, TSS, andammonia in WWTP effluent. This impact is considered less than significant.

Conventional pollutants included in this analysis are ammonia, BOD, and TSS. The anticipatedeffluent quality requirements for design for conventional pollutants are presented in Table 4.1-14. Althoughammonia can also be a toxic pollutant, it was included in this analysis as a conventional pollutant becauseit is readily and consistently removed along with BOD and TSS in the secondary treatment process. Theproposed WWTP would be designed specifically to meet the future permit limits for BOD, TSS, andammonia, with adequate capacity and proven ability to remove these pollutants. The proposed WWTPwould be designed to at least EPA Class II reliability standards, which would ensure consistent performancewith respect to meeting the BOD, TSS, and ammonia design permit limits.

The existing WWTP already consistently meets the BOD and TSS permit limits (10 mg/L,respectively) and has a good operation record with few violations. The proposed WWTP would bedesigned to produce an effluent with equal to or less than 1 mg/L of ammonia nitrogen, which is theanticipated effluent quality requirement (Table 4.1-14). Un-ionized ammonia is a component of ammonianitrogen that is known to be potentially toxic to fish at certain pH levels and temperatures. At theanticipated limit, the concentration of un-ionized ammonia, the chemical component of concern in ammonianitrogen, would be well below reported levels (0.2-0.6 mg/L) that would be potentially toxic to fish (Mingee


Table 4.1-14. Anticipated Effluent Quality Requirements for Design

Constituent Unit30-DayAverage

7-DayAverage

30-DayMedian

DailyMaximum

Flow, ADWF mgd 2.7

BOD, 5-day mg/L 10 15 25

TSS mg/L 10 15 25

Ammonia (NH4+-N) mg/L <1

Oil and grease mg/L 10

Settleable matter ml/L 0.1

Total coliform MPN/100 ml <2.2 23

Chlorine residual mg/L 0.1

Notes: ADWF = average dry weather flow.BOD, 5-day = five-day biochemical oxygen demand.

Source: Nolte and Associates 1995b.


pers. comm.). Therefore, potential water quality impacts associated with discharge of BOD, TSS, andammonia to the South Fork of Putah Creek are considered less than significant.

Implementation of the following mitigation measures from the 1994 LRDP EIR would help ensurethat concentrations of conventional pollutants are adequately controlled.

4.8-6(a) The Campus shall continue to monitor effluent discharge, in compliancewith WDR Order No. 92-040, from the wastewater treatment plant toidentify any exceedances of established WDR effluent limits.

4.8-6(b) If the effluent limits established in WDR Order No. 92-040 are exceeded,and action is required by the CVRWQCB, the Campus shall makemodifications to the pretreatment program to ensure compliance withestablished effluent limits.

4.8-6(c) The Campus shall apply for and comply with any requirements of a NPDESWDR for the proposed new wastewater treatment plant prior to plantoperation.

Mitigation Measure


4.1-6 Continued discharge of treated effluent into the South Fork of Putah Creek could resultin potential water quality degradation because of the presence of toxic pollutants inWWTP effluent. This impact is considered potentially significant.

Water quality degradation could occur as a result of the potential exceedance of one or morecriteria and standards that would likely be included as future NPDES permit limits for the proposedWWTP. Water quality criteria were evaluated for their applicability as future NPDES permit limits. Sources of water quality criteria include the NTR, the California ISWP, EPA National Ambient WaterQuality Criteria to protect freshwater aquatic life, and federal and state drinking water standards. Theselection of criteria to use was based on the recommendation of staff at the CVRWQCB (McHenry pers.comm.). Criteria were selected for each specific pollutant from three sources:

n the NTR,n EPA National Ambient Water Quality Criteria, andn federal and state drinking water standards.

Potential future water quality criteria applicable to the proposed WWTP discharge are presented in Table4.1-15. Several of the criteria listed in Table 4.1-15 will likely not be included in future permits if theCVRWQCB finds there is not reasonable potential for the constituents to exceed water quality criteria.


The Campus receives wastewater from a variety of potential non-domestic discharge sources ofthese pollutants, including laboratories, septic tanks, and cooling towers. Existing WWTP effluent datawere analyzed to identify which pollutants had been detected (refer to “Metals and Organic Compoundsin the Effluent”). Data for over 120 pollutants were analyzed, and only 16 were detected in more than 10%of the samples. Two other pollutants, hexavalent chromium and mercury, were not detected but wereincluded in the analysis because of historic detection and special concern. Of these 18 pollutants, only fourwere found to potentially exceed the future criteria when maximum and average concentrations werecompared. The four pollutants were copper, bis(2-ethylhexyl)phthalate, carbon tetrachloride, and tributyltin(Table 4.1-15). One of the detected pollutants, bis(2-ethylhexyl)phthalate, is commonly present in domesticwastewater and is not associated with any particular nondomestic discharge sources.

Because the existing WWTP uses a treatment process that is similar to that of the proposedWWTP, there is also potential for the proposed WWTP to exceed future permit limits for these or otherpollutants. Therefore, because the proposed WWTP discharge would have the potential to degrade waterquality in the South Fork of Putah Creek, this impact is considered potentially significant.

Mitigation Measure

Implementation of the following mitigation measure is required to reduce this impact to a less-than-significant level.

4.1-6 The Campus shall strictly implement the pretreatment program and aggressively enforce thelocal limits to reduce pollutant concentrations and ensure that NPDES permit limits wouldbe met. Implementation of the pretreatment program to ensure that local limits are met willinclude monitoring, inspection of facilities, education, and enforcement, all as describedabove in “Regulatory Setting” and in Appendix E.

The WWTP discharge would meet the water quality criteria and standards that would be selectedas future permit limits to ensure that water quality and beneficial uses in the South Fork of Putah Creek areprotected. The Campus pretreatment program is the primary mechanism to ensure that future permit limitsare met by the WWTP. The pretreatment program has been implemented and in progress for the past 18months. Pretreatment programs are widely recognized for achieving substantial pollutant reductions,especially in the beginning of the program (U.S. Environmental Protection Agency 1991, SacramentoRegional County Sanitation District 1995, County Sanitation Districts of Orange County 1994). TheCampus pretreatment program is continuing to be implemented to gain program momentum and providethe maximum possible level of results by the time the proposed WWTP starts up in 1999.

Local limits have been developed for the Campus pretreatment program and a plan forimplementation has been established. Refer to Appendix E for a detailed discussion of the local limitsprocess. Applicable water quality criteria and drinking water standards were considered for every pollutantrequiring a local limit, with the most restrictive criteria or standard being selected as the basis for calculatingthe local limit. Background information on the development of water quality criteria and the level ofprotection they provide is presented above under “Regulatory Setting”. In many cases, the criteria and


Table 4.1-15 Potential Future Water Quality Criteria and WWTP Effluent Data (µg/L)

Water Quality Criteria Existing WWTP ConcentrationsPollutant

Maximum Average Maximum Average

Arsenic 50.00 7.90 5.07Cadmium 4.11 1.11 0.95 0.28Chromium, total 50.00 9.70 5.21Chromium, hexavalent 15.00 10.00 ND NDCopper 18.62 12.31 * 26.00 * 22.00Lead 71.63 2.79 1.40 1.02Mercury 2.10 0.012 ND NDSelenium 20.00 5.00 1.70 0.83Silver 4.06 1.60 0.90Zinc 124.07 113.30 78.00 41.00Bis(2-ethylhexyl)phthalate 1.80 * 150.00 * 44.42Bromodichloromethane 100.00 18.00 12.67Carbon tetrachloride 0.50 * 1.60 * 0.78Chloroform 100.00 46.00 30.58Dibromochloromethane 100.00 8.60 5.55Methylene chloride 5.00 4.00 2.15Toluene 100.00 4.10 0.89Tributyltin 0.026 * 0.140 * 0.056

Notes: * = exceedance of water quality criteria.

ND = not detected.

Hardness of 110 mg/L was used to calculate the cadmium, total chromium, copper, lead, silver, and zincwater quality criteria.

Selenium and bis(2-ethylhexyl)phthalate water quality criteria are National Toxics Rule Standards.

Arsenic, total chromium, bromodichloromethane, chloroform, methylene chloride, dibromochloromethane,carbon tetrachloride, and toluene water quality criteria are EPA drinking water standards.

All other pollutant water quality criteria are EPA National Ambient Water Quality Criteria.


standards presented in Table 4.1-15 were also selected as the basis for calculating local limits. Three ofthe four pollutants with potential to exceed water quality criteria that could be included in future permit limitsalso have water quality criteria or drinking water standards that were used as the basis for calculating locallimits. Because of the relationship between local limits and the potential future permit limits, the local limitsfor the pollutants of concern in this analysis would be considered protective of water quality in the SouthFork of Putah Creek.

4.1-7 Continued discharge of treated effluent from the proposed WWTP to the South Fork ofPutah Creek could result in potential chronic toxicity to aquatic organisms. This impactis considered potentially significant.

Three-species bioassay tests conducted on the existing WWTP effluent have periodically indicatedchronic toxicity in the test organism, water flea (Ceriodaphnia dubia), with substantially fewer occurrenceswith the fathead minnow or algae. The causes of these occurrences were not identified by the testingprocedures used. There has been no apparent relationship between incidences of toxicity andconcentrations of un-ionized ammonia in the effluent. Un-ionized ammonia is generally a principal pollutantof concern with respect to aquatic life toxicity from WWTP effluent. However, the un-ionized ammonialevels in effluent from the proposed WWTP would be below threshold concentrations known to be toxicto fish and other aquatic organisms. Therefore, the potential for occurrences of chronic toxicity with testorganisms would likely be associated with toxic pollutants such as trace metals and organic compounds andwould not be associated with ammonia. The additive effect of the presence of different pollutants is alsoknown to be a factor in causing chronic toxicity in test organisms.

Although the effluent quality of the proposed WWTP should be better than that of the existingWWTP, because of the similarity of treatment processes, the effluent from the proposed WWTP couldpotentially cause occurrences of chronic toxicity. Therefore, this impact is considered potentially significant.

Mitigation Measure


4.1-7 Implement Mitigation Measure 4.1-6.

Implementation of the pretreatment program, along with enforcement of the local limits, wouldreduce the influent concentrations of toxic compounds over the long term.

The proposed WWTP would be required to test the effluent for chronic toxicity with the sameprocedures that it currently uses. If the tests conducted for the proposed WWTP indicated substantialproblems of chronic toxicity in the effluent, the CVRWQCB would likely require UC Davis to performadditional testing. Additional testing of the WWTP effluent could include weekly tests for a period of 2months. Substantial exceedance would be defined by the CVRWQCB in relation to basin-wide toxicscontrol strategies. EPA recommends that if chronic toxicity is present at levels above an established permit


limit more than 20% of the time, a toxicity reduction evaluation (TRE) should be required by the regulatoryauthority (CVRWQCB). A TRE is a systematic process developed to identify pollutants that are the causeof the toxicity, evaluate source control options to correct the problem, and then perform tests to confirmthe reduction in effluent toxicity (U.S. Environmental Protection Agency 1988). If specific threshold criteriawere consistently exceeded in the future, the CVRWQCB could require the Campus to perform a TREinvestigation.

Although not required by the current NPDES permit, additional testing could also be required bythe CVRWQCB to further assess the potential for toxicity in areas not directly related to the scope of theTRE. Additional testing could include sediment toxicity and bioaccumulation monitoring to determine ifpollutants have accumulated in sediment and fish tissues and could also be contributing to toxicity. The needfor additional testing would be dependent on the results of the TRE. The tests would only be required ifthe pollutant identified by the TRE had the potential to persist in the environment at toxic levels. If theresults indicated that the pollutant identified by the TRE was either ammonia or a volatile organic compoundwith little or no potential to cause toxicity or persist in the aquatic environment, these tests would not berequired (McHenry pers. comm.). The limitations of these additional tests are that the results would reflectpotential effects from historic discharges in the entire watershed rather than just the proposed WWTPdischarge, and that there are currently no regulatory standards with which to compare the results.

In addition, the Yolo County Department of Public Health, the CVRWQCB, and UC Davisrecently received funding from the SWRCB under a Clean Water Act 205j program grant, following avoluntary request, to perform water quality and aquatic toxicity investigations in the Cache and Putah Creekwatersheds. The specific objectives of the project are to characterize the water quality of Putah Creek,including monitoring of aquatic toxicity. The monitoring results will be used to develop implementation plansto achieve water quality objectives, if necessary, and foster comprehensive watershed management activitiesfocusing on ecosystem protection. The study is in the early planning stages and a work plan is currentlybeing developed. The results of this study will be used to further inform the local limits and pretreatmentprograms.4.1-8 Discharge of storm water to the South Fork of Putah Creek could result in long-term water

quality degradation during operation of the WWTP and associated facilities. Storm waterdischarges could result in incremental increases in the transport of pollutants from theproposed WWTP site to the South Fork of Putah Creek. This impact is consideredsignificant.

Operation of the WWTP would have the potential for long-term impacts from the discharge ofstorm water containing additional pollutants associated with chemicals used for WWTP processes, includingpetroleum-based products from vehicles and heavy machinery, and other miscellaneous wastes fromactivities such as landscape maintenance, pest management, and wash water. Additional storm water thatwould be discharged to the drainage canal along the eastern edge of the LEHR/SCDS area could potentiallyincrease the rate at which pollutants that may be associated with Landfill Disposal Unit #3 would betransported to the South Fork of Putah Creek because the canal intersects a portion of the landfill area. Long-term water quality impacts that could result from increased runoff from the WWTP site discharged


to the drainage canal that was constructed through the LEHR/SCDS area Landfill Disposal Unit #3 areaddressed in Chapter 7; please see Impact 7.2 and mitigation measure 7.2(a) and (b) in Chapter 7.

The 1994 LRDP EIR identified the following mitigation measure that applies to the project.

4.8-5(a) The Campus shall ensure that project design includes a combinationof the following Best Management Practice (BMPs), or equally effectivemeasures:

(i) Oil and grease separators shall be used to control roadway andparking lot contaminants.

(ii) Parking lots shall be cleaned and swept on a regular basis.

(iii) Peak flow reduction and infiltration practices, such as grass swales,infiltration trenches and grass filter strips shall be incorporated.

(iv) Storm drain inlets shall be labeled to educate the public of the adverseimpacts associated with dumping on receiving waters (i.e. "Don’tdump! Drains to creek!").

(v) Landscape areas, including borders shall use warm season grasses anddrought tolerant vegetation wherever feasible to reduce demand forirrigation and thereby reduce irrigation runoff.

(vi) Efficient irrigation systems shall be installed in landscaped areas tominimize runoff and evaporation and maximize the water that willreach the plant roots. Such irrigation systems include drip irrigation,soil moisture sensors, and automatic irrigation systems.

Compliance with 1994 LRDP EIR Mitigation Measure 4.8-5(a) will reduce this impact but not toa less-than-significant level.

Mitigation Measure


4.1-8 The Campus shall apply for and comply with any requirements of an NPDES GeneralIndustrial Storm Water permit for the proposed WWTP prior to plant operation.


Groundwater Quality

4.1-9 Continued discharge of treated effluent from the proposed WWTP could affectgroundwater quality due to recharge of additional pollutants into the aquifer from theSouth Fork of Putah Creek. This impact is considered less than significant.

Seepage of wastewater from the South Fork of Putah Creek could potentially result in shallowgroundwater being adversely affected by nitrates, trace metals, or organic compounds present in theWWTP effluent. Nitrate concentrations in municipal and private wells in the City of Davis have exceededthe drinking water standard. The maximum allowable concentration under state drinking water regulationsis 45 mg/L. Studies of local groundwater have indicated that the nitrates could be associated with deeppercolation of agricultural irrigation water containing dissolved nitrate from fertilizers, animal pens, anddomestic septic tanks (Dames and Moore 1990).

The proposed WWTP would have a negligible impact on nitrate concentrations in groundwaterbecause the potential for recharge occurs primarily during the winter when the water table is higher. Duringthis period, nitrates in WWTP effluent would be highly diluted in the South Fork of Putah Creek and wouldfurther decrease as a result of mixing with ambient groundwater after reaching the water table andadsorption to clay and organic matter above and below the water table.

For similar reasons, there would be no substantial change in potential groundwater contaminationfrom trace metals or organic compounds. Under existing conditions, some of the WWTP effluent couldreach the water table by percolation from the South Fork of Putah Creek. The concentrations of thesecompounds in the WWTP effluent are relatively low and would be further diminished by dilution with rainfallrecharge, mixing with ambient groundwater after reaching the water table, adsorption to clay and organicmatter above and below the water table, and chemical dispersion as the water percolates downward fromthe water table to the aquifer zones tapped by water supply wells. Additionally, the WWTP dischargewould have to meet the criteria presented in Table 4.1-15, which would be considered to be protective ofaquatic resources, such as groundwater quality. The WWTP effluent is not like a landfill or dump site,which have concentrated sources of some pollutants that can result in excess concentrations in groundwatereven after decreases from dilution, adsorption, and dispersion. Therefore, the impact of the proposedproject on groundwater quality is considered less than significant.Mitigation Measure


4.1-10 Construction and operation of the proposed solids storage basins could result in thepotential degradation of groundwater quality. This impact is considered potentiallysignificant.

Biosolids generated at the proposed WWTP could degrade shallow groundwater quality in thevicinity of the SSBs and disposal sites. The available data have indicated that the existing biosolids havemet at least Class B criteria and concentrations of trace metals have met “Exceptional Quality” criteria.


Biosolids generated at the proposed WWTP would be expected to have similar or better trace metalconcentrations. Pathogens would be removed to Class A standards for pathogen reduction by composting,or the biosolids would be landfilled, possibly applied to land if Class B criteria are met, or removed by anoutside contractor who would be responsible for disposal of biosolids according to applicable regulations.

Biosolids, although stabilized for pathogen content and human health protection, can still releasequantities of inorganic nutrients, salts, organic matter, and trace metals to water. To minimize the potentialfor seepage to the surrounding soil, the SSBs would be lined with a fabric-reinforced, synthetic membranewith a thickness of 36 millimeters (known by the trade name Hypalon). This liner is designed to preventseepage and provide protection against interior slope erosion. Hypalon is designed specifically for suchimpoundments. Factory seams are made under strict quality control measures and are field tested prior toacceptance for use. The liner would be warranted from the manufacturer for a design life of 20 years(Mingee pers. comm.). Asphalt concrete would be placed over the membrane on the bottom and aboutone-third of the way up the side slopes to protect the membrane during dredging operations. Two SSBswould be provided so that one could be emptied and inspected when empty for liner integrity while theother remains in operation. Additional protection of groundwater quality would be provided by the fact thatthe SSBs would be no more than approximately 15 feet below the surface, which is well above the seasonalgroundwater levels of 30 to 70 feet below the surface.

Biosolids that are removed from the SSBs could be placed on asphalt drying beds that are designedto limit seepage to groundwater and collect any excess water, which would be piped back to the WWTPfor further treatment. The existing EPA Part 503 regulations for the disposal of biosolids were designedwith the goal of promoting the beneficial reuse of the organic material and nutrients contained in the biosolidsas a soil amendment (U.S. Environmental Protection Agency 1994). Because limited seepage might occurdue to biosolids handling at the proposed WWTP, this impact is considered potentially significant.

Mitigation Measure

4.1-10 The Campus will install and monitor groundwater monitoring wells at the proposed WWTP,as may be required by the CVRWQCB in the future NPDES permit and monitoring programfor the facility.

Cumulative Impacts and Mitigation Measures


4.1-11 Increasing the amount of water from the proposed WWTP to the South Fork of PutahCreek, in conjunction with other Campus discharges, would cumulatively increase surfacerunoff and could affect the flow regime of Putah Creek. This impact is considered lessthan significant.


The discharge from the existing WWTP is the farthest downstream of the four other existingpermitted discharges, the storm water discharge from the Arboretum Waterway (via the storm waterpumping pond), and one proposed permitted discharge from the Campus landfill groundwater treatmentsystem. The other existing permitted discharges upstream of the existing WWTP are from the Putah CreekResearch Facility, the Aquatic Center, and the USDA Aquatic Weed Control Laboratory. There are alsostorm water discharges from the South Campus area, including the LEHR/SCDS area, the Campus airport,and the Caltrans detention basin. These discharge locations were presented in Figure 4.1-2.

Cumulative effects on flow conditions would occur only when there is enough flow in the creek tointerconnect the six discharge locations with continuous flow. Pursuant to a recent judicial decision in PutahCreek Water Cases, the mean daily flow near Old Davis Road would be at least 5 cfs, with aninstantaneous minimum of 4.5 cfs. This decision is subject to appeal, however, and it is uncertain if or whenthe new minimum flows would be implemented. This minimum flow would be sufficient to interconnect allthe Campus discharges and allow them to mix in the creek. A detailed analysis of the cumulative impactson water quality of the permitted Campus discharges and storm water discharges from the ArboretumWaterway is presented in Appendix D, “Water Quality Technical Appendix”.

The existing WWTP discharge contributes 48% of the total permitted Campus discharges duringthe dry season and 21% during the first fall storm. The proposed WWTP would contribute 61% and 32%of the total discharges during the dry season and first fall storm, respectively. During the dry season, thecombined discharges would continue to be approximately the same magnitude as the 5 cfs of court-orderedinstream flow arriving at the uppermost discharge point. Combining the discharges would not increase flowto any thresholds that would trigger new effects, such as increasing flow continuity or spilling out of the lowflow channel. Therefore, this impact is considered less than significant.

Mitigation Measure



4.1-12 The proposed WWTP, in conjunction with other permitted wastewater discharges andstorm water discharges from the Campus and future Campus growth, could result incumulative water quality degradation in Putah Creek. This impact is consideredpotentially significant.

An analysis was prepared to determine whether combining more than one permitted discharge orthe Arboretum storm water discharge could result in significant cumulative effects on the creek (AppendixD). The model assumed existing conditions with the new WWTP replacing the existing WWTP. Themodel results were compared to potentially applicable water quality criteria. This approach was selectedby the Campus to ensure that potential water quality issues would be identified. Some exceedances of the


selected water quality criteria by individual discharges were identified, but no cumulative impacts ofcombining discharges were found.

This analysis of cumulative water quality impacts includes a quantitative analysis of permittedCampus wastewater discharges, the discharge of fall-season storm water from the Arboretum Waterway,and the proposed discharge from the landfill groundwater treatment system (Appendix D). Winter stormwater runoff from the Arboretum Waterway was analyzed qualitatively. Cumulative impacts would resultfrom the potential discharge of toxic pollutants from these sources. CEQA defines cumulative impacts as“two or more individual effects which, when considered together, are considerable or which compound orincrease other environmental impacts”. For the purposes of this analysis, a cumulative impact is defined astwo or more individual discharges which, when combined in the creek, result in concentrations in the creekthat would exceed water quality criteria beyond those found in individual discharges. There are no otherknown significant sources of conventional pollutants such as BOD, TSS, or ammonia in permitted or stormwater discharges to the South Fork of Putah Creek, so there would be no cumulative impacts associatedwith these pollutants.

The quantitative analysis of cumulative impacts from Campus discharges to the South Fork of PutahCreek was performed using a mass balance model. The six discharges included in the analysis included thefollowing:

n Putah Creek Research Facility,n landfill groundwater treatment system (proposed future discharge),n Aquatic Center,n USDA Aquatic Weed Control Laboratory,n Central Campus storm water pumping pond, andn existing and proposed WWTP.

Cumulative impacts of the permitted discharges were analyzed by determining the concentration ofpollutants in the South Fork of Putah Creek just below all discharges. Existing conditions were analyzedunder four Putah Creek flow conditions: Court-Ordered Release - Dry Season, Court-Ordered Release- Fall Storm, Existing Release - Dry Season, and Existing Release - Fall Storm. Values for both maximumand average pollutant concentrations were calculated from existing WWTP effluent data collected betweenApril and July 1996 and used to estimate final pollutant concentrations. The most recent available waterquality data for the other discharges were used to estimate maximum and average pollutant concentrationsfor these discharges. These concentrations were then compared with applicable corresponding waterquality criteria for each value. A detailed discussion of the model analysis and results is presented inAppendix D.

The model assumed that the greatest potential for cumulative impacts associated with permittedCampus discharges to the South Fork of Putah Creek would occur when the assumed minimum creek flowof 5 cfs would interconnect the discharges and mix in the creek (Court- Ordered - Dry Season condition). This condition would result in the least amount of dilution in the creek with all Campus discharges still beinginterconnected. Under the Court Ordered Release - Dry Season condition, three of 18 pollutants of


concern would exceed one or both criteria: bis(2-ethylhexyl)phthalate, carbon tetrachloride, and tributyltin. Two pollutants, bis(2-ethylhexyl)phthalate and tributyltin, would also exceed their respective criteria in theother three simulated flow conditions. The pollutants of concern and their respective criteria were presentedabove in Table 4.1-15. The general conclusion from the results of the cumulative analysis is that theCampus discharges, when combined with the minimum creek flow, dilute one another and that any potentialfor cumulative impacts is consequently less than the direct impacts of a particular discharge (i.e., end-of-pipe conditions).

The overall worst-case condition for water quality in the South Fork of Putah Creek would occurin the Existing Release - Dry Season condition, when individual permitted discharges are isolated in thecreek. The Existing Release - Dry Season condition would result in the highest concentrations in the SouthFork of Putah Creek because there would be no dilution. In this condition, the estimated pollutantconcentrations in the creek for existing conditions would be the same as the individual discharges (Table4.1-15), or, in other words, end-of-pipe conditions. Four of 18 pollutants of concern would exceed oneor both criteria in the WWTP discharge, including copper, bis(2-ethylhexyl)phthalate, carbon tetrachloride,and tributyltin. With the exception of copper, these are the same pollutants potentially exceeding criteriaunder the Court-Ordered Release - Dry Season condition, as described above.

The other permitted discharges were found to have a minimal effect on water quality in the SouthFork of Putah Creek. Cumulative impacts associated with storm water from the Arboretum Waterwayunder fall and winter conditions would also be minimal. In general, low volumes of storm water from theArboretum Waterway would be diluted by the increased creek flow resulting from fall storms and theWWTP discharge. In winter, the increased volume of storm water and the WWTP discharge would behighly diluted with increased creek flows. However, because of the historic discharge from the coolingtowers and the continued discharge of urban and irrigation runoff from the Central Campus to theArboretum Waterway, the discharge of storm water from the Arboretum Waterway could containaccumulated pollutants and potentially degrade the water quality in the South Fork of Putah Creek.

In summary, no cumulative impacts due to combining more than one discharge were identified;however, individual discharges would potentially exceed some of the selected water quality criteria. Mostof these criteria currently are not included in Campus discharge permits. However, to be conservative, theCampus has chosen to identify these effects as potentially significant and adopt mitigation to reduce theimpact to a less-than-significant level.

Cumulative water quality impacts to Putah Creek could also result from increased contaminants instorm water runoff from additional impervious surfaces associated with development allowed under the1994 LRDP. Specific potential sources include the LEHR/SCDS area drainage and Campus airport stormwater discharges. This impact was identified as significant in the 1994 LRDP and the following mitigationmeasure that applies to the project was adopted.

4.8-5(a) The Campus shall ensure that project design includes a combinationof the following Best Management Practice (BMPs), or equally effectivemeasures:


(i) Oil and grease separators shall be used to control roadway andparking lot contaminants.

(ii) Parking lots shall be cleaned and swept on a regular basis.

(iii) Peak flow reduction and infiltration practices, such as grass swales,infiltration trenches and grass filter strips shall be incorporated.

(iv) Storm drain inlets shall be labeled to educate the public ofthe adverse impacts associated with dumping on receivingwaters (i.e. "Don't dump! Drains to creek!").

(v) Landscape areas, including borders shall use warm seasongrasses and drought tolerant vegetation wherever feasible toreduce demand for irrigation and thereby reduce irrigationrunoff.

(vi) Efficient irrigation systems shall be installed in landscapedareas to minimize runoff and evaporation and maximize thewater that will reach the plant roots. Such irrigation systemsinclude drip irrigation, soil moisture sensors, and automaticsystems.

Mitigation Measure

Implementation of the following mitigation measures in combination with LRDP Mitigation Measure4.8-5(a) would reduce cumulative water quality impacts to a less-than-significant level.

4.1-12(a) Implement Mitigation Measure 4.1-6.

4.1-12(b) The Campus shall continue to implement the source control program to reduce pollutantsof concern in cooling tower discharges based on the work plan submitted by the Campusin February 1995 to the CVRWQCB. The work plan describes a source control programto reduce pollutants of concern including arsenic, hexavalent chromium, copper, andselenium in cooling discharges.

The Campus has already begun implementation of this mitigation measure. For example, the useof tributyltin in cooling towers has already been eliminated.

4.1-13 Cumulative agricultural and urban development in the region, in conjunction with theproposed WWTP and 1994 LRDP development, could reduce receiving water quality. This impact is considered significant and unavoidable.


The 1994 LRDP EIR identified water quality reduction resulting from cumulative urban andagricultural development in the Putah Creek watershed as a significant and unavoidable impact. Theimpacts would result from sediment and erosion caused by construction activities, which could have short-and long-term effects on water quality. Urban development and the associated increase in impervioussurfaces would alter existing water quality because of the increase in the rate and amount of runoff. Theprimary sources of runoff and pollutants would be roads, parking lots, landscaped areas, and industrialactivities. Agricultural development within the watershed could contribute loads of salts, nutrients,pesticides, and heavy metals in addition to sediment. None of the jurisdictions in the Putah Creekwatershed are currently covered by a municipal storm water NPDES permit (University of California, Davis1994).

Increased loads of pollutants generated from these activities could adversely affect water qualityand the associated beneficial uses, such as recreation and fish and wildlife habitat.

The following mitigation measures were identified in the 1994 LRDP EIR to reduce the impact;however, the feasibility and/or implementation of LRDP Mitigation Measures 4.8-8(b) and 4.8-8(c) cannotbe guaranteed by the University because they fall within other jurisdictions to enforce and monitor. Therefore, this impact is considered significant and unavoidable.

4.8-8(a) Implement Mitigation Measures 4.8-4(a) and (b), 4.8-5(a) and (b), and 4.8-6(a) through (c).

4.8-8(b) When the EPA adopts NPDES Municipal Storm Water Permit requirementsfor small municipalities, local jurisdictions in the Putah Creek watershedwould apply for, obtain, and implement a NPDES Municipal Storm WaterPermit in accordance with EPA requirements.

4.8-8(c) Comprehensive storm water pollution prevention plans and monitoringprograms would be implemented by all storm water dischargers associatedwith specified industrial and construction activities, in compliance with theState's general permits. Such plans shall include best managementpractices or equally effective measures.

A specific potential source of storm water that could contribute to cumulative water quality impactsis the LEHR/SCDS area. The water quality in the South Fork of Putah Creek could potentially bedegraded by the addition of pollutants that enter in storm drains and surface runoff from the LEHR/SCDSarea, in particular from the former LEHR site and old WWTP. A limited amount of storm water data fromthe LEHR site indicate that storm water contains metals such as antimony, lead, and zinc. Investigationsare still ongoing at the LEHR/SCDS site to provide a risk assessment on the potential exposure for the area. In addition, a surface water barrier and diversion and concrete lining of the drainage canal in the vicinityof Landfill Disposal Unit #3 are being considered; these measures would reduce the potential for pollutants


in surface runoff to reach the South Fork of Putah Creek from this area of the SCDS site. This issue isaddressed in Chapter 7 of this draft EIR.

Mitigation Measure

4.1-13 No additional feasible mitigation has been identified.


4.1-14 Cumulative development in the Lower Cache-Putah Groundwater Basin, in conjunctionwith the proposed WWTP, would increase the amount of impervious surface and reducegroundwater recharge potential. This impact is considered significant and unavoidable.

The 1994 LRDP EIR identified the cumulative reduction of groundwater recharge potential in theLower Cache-Putah Groundwater Basin as a significant and unavoidable impact.

The proposed WWTP, in combination with other regional development in the Lower Cache-PutahCreek Groundwater Basin, would increase the amount of impervious surface coverage and reduce theamount of available acreage suitable for groundwater recharge. As described earlier in this chapter and inthe 1994 LRDP EIR, the regional groundwater aquifers appear to recharge, and there is no evidence ofgroundwater overdraft (such as subsidence). Because both the shallow and deep aquifers serve as sourcesof domestic and agricultural water supply, recharge of the aquifers is important to maintaining safe yield ofthe groundwater resources. Therefore, coverage of undeveloped land with impervious surface could reducethe amount and rate of groundwater recharge.

The following mitigation measures were identified in the 1994 LRDP EIR to reduce the impact toa less-than-significant level; however, the feasibility and/or implementation of Mitigation Measure 4.8-9(b)cannot be guaranteed by the University of California because it falls within other jurisdictions to enforce andmonitor. For this reason, the University must consider the impact significant and unavoidable.

4.8-9(a) Implement Mitigation Measure 4.8-3(a) and (b).

4.8-9(b) Jurisdictions in the Lower-Cache Putah Creek Groundwater Basin shouldencourage development to be accomplished in a manner that wouldmaximize percolation and infiltration of precipitation into the underlyinggroundwater aquifers through the use of pervious paving materials, clusterdevelopment, retention of natural drainage areas, and identification andretention of flood plains and areas of high recharge potential.

Mitigation Measure



Chapter 4.2 Air Quality

INTRODUCTION

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), thisanalysis focuses on air quality during facility operations, potential exposure of sensitive receptors topollutants, and potential exposure of sensitive receptors to odors. The project’s contribution to cumulativeimpacts related to criteria pollutants and toxic air pollutants also is addressed. Potential air quality impactsrelated to construction, vehicle traffic, and climate were adequately addressed in the 1994 LRDP EIR andare not addressed in this chapter.

This chapter of the EIR analyzes air quality impacts associated with the proposed project. Impactsevaluated include (1) operational criteria pollutant emissions, (2) odor emissions, (3) toxic air contaminant(TAC) emissions, and (4) cumulative criteria pollutant emissions and TAC emissions. The evaluation ofimpacts of increased levels of TACs is based on an updated health risk assessment (HRA) prepared forthis EIR and contained in Appendix G of this document. This chapter contains a summary of the updatedHRA.


General Background and Overview

Air pollutants can adversely affect human health. Air quality levels are commonly reported as aPollution Standard Index (PSI). The PSI reflects the concentration of a single air pollutant based on thepollutant of most concern at a specific time of the year. This method shows the general relationship betweenmeteorology, pollutant concentration, and air quality. The PSI often rises during summer days, when it isusually warm and calm.

Climate and Meteorology

A number of important factors determine local and regional air quality. The most critical are thequantity, type, and location of pollutant sources. Meteorological and topographical conditions also areextremely important.


Geography plays a significant role in weather patterns throughout the California Central Valley,including the Campus area. The Central Valley, which extends from south of Bakersfield to north ofRedding, is bordered by the Sierra Nevada on the east, the Coast Ranges on the west, the TehachapiRange on the south, and the Cascade Range on the north. These mountain ranges tend to buffer the valleyfrom the marine weather systems that originate over the Pacific and are drawn inland by the jet stream. Theonly breach in this barrier is the Carquinez Straits, which expose the midsection of the Central Valley toPacific Coast marine weather patterns. The Sacramento area is noticeably affected by this marine influence,which helps moderate climatic extremes. The cooling effect of the sea breezes is especially evident onsummer evenings.

The UC Davis campus is in Yolo and Solano counties, both of which are within the SacramentoValley Air Basin (SVAB). Climate in the Davis area is characterized by long, hot, dry summers and short,cool winters. Summer temperatures range from an average low of 55°F to an average high of 98°F, withtemperatures in excess of 100°F common. This high average summer temperature, combined with verylow relative humidity, produces hot, dry summers. Temperature inversions, which limit the verticaldispersion of air pollutants, concentrate pollutants and exacerbate air pollution problems. These inversionsare prevalent at night during autumn and winter and occasionally persist throughout the day. Wintertemperatures range from an average low of 37°F to an average high of 61°F, with occasional overnightfreezing temperatures. Annual precipitation averages 17 inches, with 88% of the precipitation falling inNovember through April. Predominant winds are from the south 35% of the time, at a speed of about 4miles per hour. A wind rose indicating wind and speed direction for the project area is shown in Figure 4.2-1.

Criteria Pollutants

Historically, air quality laws and regulations have divided airborne pollutants into two broadcategories: “criteria pollutants” and “TACs”. Federal and state air quality standards have been establishedfor six ambient air pollutants, commonly referred to as “criteria” air pollutants. In general, “criteria”pollutants are pervasive constituents, such as those emitted in vast quantities by use of fossil fuels. Thesestandards were developed primarily to protect human health and welfare and were so named because theU.S. Environmental Protection Agency (EPA) published criteria documents to justify the choice of eachstandard. The criteria air pollutants for which federal and state ambient standards have been establishedinclude ozone (O3), carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), inhalableparticulates (PM10), and lead. Criteria pollutants are regulated separately from TACs at both the federaland state levels.

The SVAB includes nine counties—Shasta, Tehama, Glenn, Butte, Colusa, Sutter, Yuba, Yolo,and Sacramento—and the valley portion of two other counties, Solano and Placer. The criteria pollutantsof greatest concern in the SVAB include O3, PM10, and CO. Although high NOx concentrations are notfound in the SVAB, NOx plays a critical role in O3 formation. Lead and SO2 are not considered criticalcriteria pollutants because they are not pervasive in the SVAB and because they will not be emitted insubstantial quantities by the proposed project. Information on critical criteria pollutants that are of concernto the Yolo-Solano Air Quality Management District


(YSAQMD) and EPA (such as chemical form, generation mechanisms, and environmental fate) is presentedbelow. Health effects of criteria pollutants of regulatory concern in the SVAB are described in Table 4.2-1.

Carbon Monoxide

CO is an odorless, invisible gas usually formed as the result of incomplete combustion of organicsubstances. As presented in Table 4.2-1, high levels of CO can impair oxygen transport in thebloodstream, thereby aggravating cardiovascular disease and also causing fatigue, headaches, and dizziness. Motor vehicles are a primary source of CO. CO tends to dissipate rapidly into the atmosphere, andconsequently, violations of the CO standard are generally limited to major intersections during peak-hourtraffic conditions.

Ozone/Nitrogen Oxides

Reactive organic gases (ROG) and NOx are primary pollutants that are emitted directly into theenvironment as exhaust from motor vehicles and other combustion sources. Secondary or indirectpollutants are formed in the atmosphere, usually as the result of a reaction involving primary pollutants. O3

is a secondary pollutant that forms as a result of the interaction of ultraviolet light, ROG, and NOx. Duringsummer, O3 is also of primary concern; a PSI of 100 is the maximum O3 level at which the federalgovernment considers air quality to be healthy. The major effects of O3 and other components ofphotochemical smog include reductions in plant growth and crop yield, chemical deterioration of variousmaterials, and irritation of the respiratory system and eyes.

A highly reactive molecule, O3 readily combines with many different components of the atmosphere. Consequently, high levels of O3 tend to exist only while high ROGs and NOx levels are present to sustainthe O3 formation process. Once the precursors have been depleted, O3 levels rapidly decline. Motorvehicles are a primary source of ROGs and NOx.

Particulate Matter

Particulate matter consists of small liquid droplets or solid particles suspended in the atmospherethat are generated by industrial and agricultural operations, motor vehicle exhaust, stationary combustionsources, atmospheric photochemical reactions, construction activities, and agricultural waste burning.

Current EPA standards define acceptable concentrations of particulates that are smaller than 10microns in diameter, referred to as PM10. Particulate matter can cause a wide range of health and safetyeffects, including respiratory irritation, visibility reduction, and soiling of structures and materials.


Table 4.2-1. Health Effects Summary of Criteria Air Pollutants of Regulatory Concern in the SVAB

Air Pollutant Adverse Effects

Ozone (O3) Eye irritation

Respiratory function impairment

Carbon monoxide (CO) Impairment of oxygen transport in the bloodstream, increase ofcarboxyhemoglobin

Aggravation of cardiovascular disease

Impairment of central nervous system function

Fatigue, headache, confusion, dizziness

Can be fatal in the case of very high concentrations in enclosedplaces

Particulate matter (PM10) Increased risk of chronic respiratory disease with long exposure

Altered lung function in children

In combination with SO2, may produce acute illness

Particulate matter 10 microns or less in size (PM10) may lodge inand/or irritate the lungs

Source: Bay Area Air Quality Management District 1985.


Ambient Standards for Criteria Pollutants

Air quality is evaluated based on ambient air quality standards developed by federal and stateagencies. The Clean Air Act (CAA) of 1970 established national ambient air quality standards (NAAQS),with states retaining the option to adopt more stringent standards or to include other specific pollutants. Because California had standards in place before federal standards were established, and because of uniquemeteorological problems in the state, there is considerable diversity between state and federal standardsin effect in California, as shown in Table 4.2-2.

The NAAQS are the levels of air quality considered by regulators to be necessary to protect thepublic health and welfare. The “primary” standards are levels of air quality necessary, with an adequatemargin of safety, to protect the public health. The primary standards are designed to protect segments ofthe public considered to be most susceptible to respiratory distress, including asthmatics, children, theelderly, people weak from other illness or disease, and persons involved in heavy work or exercise. Healthy adults can tolerate periodic exposure to air pollution levels somewhat above these standards beforeadverse health effects are observed. “Secondary” standards are designed to protect the public welfare fromany known or anticipated adverse effects of a pollutant.

In addition to the six criteria pollutants that are regulated by both the state and federal governments,four pollutants are regulated by the state only: sulfates, hydrogen sulfide, vinyl chloride, and visibility-reducing particles. The standards for these pollutants also are presented in Table 4.2-2. The status ofsulfates, hydrogen sulfide, and visibility-reducing particles is unclassified in the SVAB because monitoringdata on these pollutants are limited. State law does not require a designation for vinyl chloride.

The hydrogen sulfide standard was created to reduce odors. Hydrogen sulfide typically createssmells similar to rotten eggs. Hydrogen sulfide is produced in petroleum processing, in geothermal powerplants, and by the decomposition of organic matter under anaerobic conditions (such as those that can occurin wastewater treatment systems).

Air Quality Monitoring Results

The California Air Resources Board (CARB) and YSAQMD maintain ambient air qualitymonitoring stations at numerous locations throughout the SVAB. The stations measure criteria pollutantlevels and assist in the determination of agricultural “burn” days. The monitoring station for the Davis area,operated by the CARB, is on the Campus, west of Highway 113 and south of Hutchison Drive. This airquality monitoring station collects O3 data. The closest monitoring station that collects CO and PM10 datais in Woodland. Table 4.2-3 is a summary of the highest annual concentrations of O3, CO, and PM10 for1988-1994, the most recent 7-year period for which data are available. In Table 4.2-3, ambient airpollutant concentrations are compared with the state ambient air quality standards, which are more stringentthan the corresponding federal standards. Measured CO levels nearest to the project site did not violatethe state 1-hour or 8-hour standards during 1988-1994. Table 4.2-3 shows that the PM10 standard was

Table 4.2-2. Ambient Air Quality Standards Applicable in California

Standard, asparts per million

Standard,as microgramsper cubic meter Violation CriteriaPollutant Symbol Average Time

California National California National California National

Ozone O3 1 hour 0.09 0.12 180 235 If exceeded If exceeded on more than 3days in 3 years

Carbon monoxide CO 8 hours 9.0 9 10,000 10,000 If exceeded If exceeded on more than 1day per year

1 hour 20 35 23,000 40,000 If exceeded If exceeded on more than 1day per year

(Lake Tahoe only) 8 hours 6 N/A 7,000 N/A If exceeded N/A

Nitrogen dioxide NO2 Annual average 1 hour N/A0.25

0.053N/A

N/A470

100N/A

N/AIf exceeded

If exceededN/A

Sulfur dioxide SO2 Annual average24 hours

N/A0.04

0.030.14

N/A105

80365

N/AIf exceeded

If exceededIf exceeded on more than 1day per year

1 hour 0.25 N/A 655 N/A N/A N/AHydrogen sulfide H2S 1 hour 0.03 N/A 42 N/A If equaled or

exceededN/A

Vinyl chloride C2H3Cl 24 hours 0.010 N/A 26 N/A If equaled orexceeded

N/A

Inhalable particulate matter

PM10 Annual geometric meanAnnual arithmetic mean24 hours

N/AN/AN/A

N/AN/AN/A

30N/A50

N/A50150

If exceededN/AN/A

N/AIf exceededIf exceeded on more than 1day per year

Sulfate particles SO4 24 hours N/A N/A 25 N/A If equaled orexceeded

N/A

Lead particles Pb Calendar quarter N/A N/A N/A 1.5 N/A If exceeded no more than 1day per year

30 days N/A N/A 1.5 N/A If equaled orexceeded

N/A

Notes: All standards are based on measurements at 25°C and 1 atmosphere pressure.National standards shown are the primary (health effects) standards.N/A = not applicable.

Table 4.2-3. Criteria Air Pollutant Monitoring Summary, 1988-1994

Monitoring Data by Yeara

Pollutant1988 1989 1990 1991 1992 1993 1994

Ozone (O3)

State 1-hour standard (ppm)b 0.09 0.09 0.09 0.09 0.09 0.09 0.09

Highest 1-hour average (ppm)b *0.11 *0.10 *0.11 *0.10 *0.12 *0.13 *0.10

Violations of standard 15 1 4 4 20 4 4

Carbon Monoxide (CO)


Highest 1-hour average (ppm)b 9.0 13.0 12.0 7.0 7.0 6.0 6.6



Highest 8-hour average (ppm)b 4.9 5.4 5.0 3.5 3.9 3.4 5.1


Particulate Matter (PM10)

State 24-hour standard (µg/m3)c 50 50 50 50 50 50 50

Highest 24-hour average (µg/m3)c *96 *113 *80 *102 *103 *96 *84


State annual geometric mean standard(µg/m3)c

30 30 30 30 30 30 30

Annual geometric mean (µg/m3)c *33.6 *30.4 25.8 *39.1 *37.6 25.5 26.0Notes: * = value is in excess of California standards.

a Ozone data are from the UC Davis campus. PM10 (1988-1994) and CO (1988-1993) dataare from the West Main Street station in Woodland. CO data (1994) are from the DavisRussell Boulevard monitoring station.

b ppm = parts per million.c µg/m3 = micrograms per cubic meter.

Source: California Air Resources Board 1989-1995.


violated regularly at the Woodland monitoring station during this 7-year period. Also, the O3 standard wasviolated during each of these years.

The standards for NOx, SO2, and lead are being met within the region, and trends in historical dataon ambient concentrations of these pollutants do not indicate that state or federal standards will beexceeded in the future.

California has adopted ambient standards that are more stringent than the federal standards forcriteria air pollutants. Under the California Clean Air Act (patterned after the federal CAA), areas aredesignated as “attainment areas”, “nonattainment areas”, or “unclassified” with respect to meeting stateambient air quality standards. The SVAB is a nonattainment area for O3 and PM10 under state standards. The SVAB also exceeds the CO standard in some urban areas but not within Solano or Yolo County. Solano and Yolo counties are designated as an attainment area under state and federal CO standards.

Toxic Air Contaminants

TACs are a category of air pollutants that are highly poisonous in small doses. Examples includecertain chlorinated hydrocarbons, certain metals, and asbestos. Adverse health effects of TACs may becarcinogenic (cancer causing), short-term (acute) non-carcinogenic, and long-term (chronic) non-carcinogenic. Several hundred such pollutants are currently regulated under various federal, state, and localprograms.

Toxic air contaminants are generated by various sources, including stationary sources, such as drycleaners, gas stations, and laboratories; mobile sources, such as automobiles, aircraft, railroads; naturalsources, such as wind-blown dust and wildfires; and area sources, such as farms, construction sites, andresidential areas.

The Davis area has many typical community sources of TACs, including dry cleaners, automobiles,and research laboratories. Frequent crop burning in the Davis area is also a substantial source of TACs. Other sources of TAC emissions in the Davis area are UC Davis research laboratories, the CampusWWTP, the Campus pathological waste incinerator, and other miscellaneous sources.

Monitoring stations for TACs are located throughout the state. These stations, maintained eitherby the CARB or the local air quality district, monitor and record levels of various organic gases and metalsin air. The YSAQMD does not conduct TAC monitoring within its jurisdiction.

The TAC monitoring station closest to Davis is in Citrus Heights, northeast of the City ofSacramento, and is operated by the CARB. The land uses in the vicinity of the monitoring station are highlyurban and are different from those near UC Davis. Data from this monitoring station are not consideredrepresentative of background concentrations in Davis because concentrations of many TACs are highlydependent on the proximity and types of contaminant sources.

One EPA study provides a general idea of the importance of community sources of air toxics interms of health risk. This study, which considered cancer-related health risks resulting from air toxics in five


cities, evaluated the relative contribution to cancer incidence of a number of common city sources of airtoxics, as shown in Table 4.2-4. As the table indicates, road vehicles were found to cause more than 50%of the air-toxics-related health risk in the cities studied. Industrial sources, such as chrome platers, solventusers, and other manufacturing, were responsible for more than 20% of the identified risk. Other commoncommunity sources, such as fireplaces, gasoline stations, and hospital sterilizers, made up about 10% of therisk.

Although this study is not specific to Davis, the results can be viewed as indicative of the probablescale and relative importance of sources of air-toxics-related health risk likely to exist in the Davis area. Specifically, it is likely that automobiles are the major source of air toxics emissions and related health riskin Davis. Davis has little industry so it probably has less industry-related air toxics health risk than the citiesstudied. However, area agricultural operations (including field burning) probably contribute to the air toxicshealth risk. Overall, the EPA study found that the average cancer incidence attributable to airborne toxicsubstances was 5.8 cases of cancer per year per million city residents. If this is considered over an averagelifetime of approximately 70 years (the standard lifetime considered in HRAs), the lifetime cancer risk fromair toxics would be 400 cases of cancer per million city residents.

Odors

An individual’s sensory perception of odors has four major dimensions: detectability, intensity,character, and hedonic tone. Detectability consists of two components: the detection threshold andrecognition threshold. The detection threshold is the lowest concentration of an odor that will elicit asensory response; at this concentration there is an awareness of the presence of an added substance, butnot necessarily an odor sensation. The recognition threshold, however, is the minimum concentration thatis recognized as having a characteristic odor quality by a population. Odor intensity refers to an individual’sperceived strength of the odor sensation. Odor character is what the substance smells like (e.g., fish, hay,sewer, turpentine, ammonia). Hedonic tone is a categorical judgment of the relative pleasantness orunpleasantness of the odor and is influenced by factors such as subjective experience and frequency ofoccurrence. Each of these elements plays a role in an individual’s identification of odor impacts.

Currently, there are several odor emission sources on the Campus. The major odor emissionsource is animal waste associated with confined animal facilities. Other sources include the WWTP, motorvehicles, and the Campus landfill.


Table 4.2-4. Sources of City Resident Cancer Cases(From EPA Five-City Cancer Study)

Carcinogenic Air Emissions SourceRelative Contribution to Air-Toxics-Related Cancer

Incidence (percentage)

Road vehicles (includes automobiles andtrucks)

55

Chrome platers 9

Solvent use 7

Wood smoke (includes fireplaces) 6

Comfort cooling towers 5

External combustion or incineration 4

Industrial cooling towers 3

Gasoline marketing 2

Ethylene oxide sterilizers 2

Chemical manufacturing 1

Refining 1

Iron and steel industry < 1

Glass manufacturing < 1

Refractory manufacturing (includesaluminum and silica industry)

< 1

Publicly owned treatment works (includessewage treatment plants)

< 1

Nonferrous metal industry < 1

Other 3

Source: E. H. Pechan & Associates, Inc. 1990.U.S. Environmental Protection Agency 1989.


Sensitive Receptors

Some receptors are considered more sensitive than others to air pollutants and odors. The reasonfor increased sensitivity includes potential for health problems, proximity to the emissions source, or durationof exposure to air pollutants. People in primary and secondary schools, hospitals, and convalescent homesare considered to be sensitive to poor air quality. This is because the very young, the old, and the ill(immunocompromised) are more susceptible to respiratory infections and other air-quality-related healthproblems than the general public. Residential neighborhoods are considered sensitive areas for poor airquality and odors because people are usually at their residences for extended periods over many years. People engaged in recreational activities are often moderately sensitive to air pollution because vigorousexercise places a high demand on human respiratory function.

Sensitive receptors on the Campus include the student and family housing complexes, day carecenters, recreation areas, and nearby off-Campus residential and recreation areas to the north, south, andeast.

REGULATORY SETTING

Federal Regulations

Criteria Pollutants

As described earlier, national ambient air quality standards have been established for the six“criteria” air pollutants described above. Because of monitored violations of the federal O3 standards, eachof the air districts in the Sacramento metropolitan area was required to prepare a plan that would describehow the area would eventually “attain” the federal O3 standard. The Sacramento Area Regional OzoneAttainment Plan was submitted to EPA on November 15, 1994. This plan was prepared and adoptedby five districts in the Sacramento area, including the YSAQMD. This plan, designed to bring theSacramento area into attainment with the federal O3 standard by 2005, is currently being reviewed by theEPA. The plan does not contain additional measures that would apply to the proposed project.


Prior to 1990, the federal CAA regulated TACs through the National Emission Standards forHazardous Air Pollutants (NESHAPS). The NESHAPS program proceeded very slowly and regulatedonly a few pollutants, such as asbestos, beryllium, mercury, and vinyl chloride from specific sources. Thesestandards were a combination of emission limiting and administrative regulations. The NESHAPS providedspecific emission limits in addition to design and operation specifications. Administrative reporting andmonitoring requirements under the NESHAPS program are extensive. These regulations apply to bothexisting and new facilities. The standards were developed based solely on health considerations withoutconsideration of economic impacts.


The 1990 Clean Air Act Amendments (CAAA) set forth new requirements for sources of routinelyreleased TACs. The new NESHAPS program, summarized in Title III of the federal CAAA, does thefollowing: (1) expands the chemical list to include a total of 189 hazardous air pollutants; (2) directs theEPA Administrator to develop standards for hazardous air pollutants; (3) directs EPA to investigate the riskof hazardous air pollutants in urban areas, including performing monitoring and analysis; and (4) includesconsideration for cost of controls.

State Regulations

The CARB, California’s state air quality management agency, regulates mobile emissions sourcesand oversees the activities of air pollution control districts (APCDs) and air quality management districts(AQMDs). The CARB regulates local air quality indirectly by establishing state ambient air qualitystandards and vehicle emission standards, by conducting research activities, and through its planning andcoordinating activities.

The implementation of the California CAA is the responsibility of every APCD and AQMD in thestate. The California CAA requires the districts to protect the public health. To protect public health, eachAPCD or AQMD is required to prepare an air quality attainment plan (AQAP) to achieve an annual 5%reduction for each non-attainment criteria pollutant or its precursors. The California CAA requires that theAPCDs and AQMDs review the AQAPs every three years to assess the effectiveness of the program andquantify the emission reductions actually achieved.


The first legislation in California to deal with ambient TACs was Assembly Bill (AB) 1807 (alsoknown as the Tanner Bill), adopted in 1983. The Tanner Bill established a statewide process to determinethe need for, and methods to set, standards for TACs. The legislative intent of the law is:

n to identify TACs,n to determine priorities for control,n to achieve early control,n to promote advanced control technologies and alternative processes,n to assist local APCDs, andn to provide a consistent level of protection throughout the state.

Since the 1980s, the CARB has researched and evaluated approximately 50 TACs. In 1992, theCalifornia Legislature passed AB 2728, which directed the CARB to add to its list of TACs the 189hazardous air pollutants from the federal 1990 CAA. As of July 1992, the CARB had identified a total of18 substances as TACs. A number of other substances have yet to be reviewed for inclusion in the list orhave not been evaluated because of limited availability of pertinent health information.

The Air Toxics “Hot Spots” Information and Assessment Act of 1987, AB 2588, provides for theregulation of more than 200 TACs, including all 18 of the designated TACs. Under AB 2588, specifiedfacilities must submit to the local air pollution control agency a comprehensive emissions inventory of these


regulated substances. After the local air pollution control agency receives completed emission inventories,it is required to identify high priority facilities; these high-priority facilities must perform HRAs.

The Campus prepared an HRA that evaluated TAC emissions related to the 1994 LRDP, outsideof AB 2588 requirements. An updated HRA was prepared for the proposed project. The HRA isdescribed in Appendix G. The methodology and results of the updated HRA are discussed below under“Impacts and Mitigation Measures”.

Title 8 of the California Code of Regulations (CCR) contains California Occupational Safety andHealth Administration (Cal/OSHA) requirements for fume hoods. The regulations focus on worker healthand safety, and require certain design features to protect laboratory personnel in their work. Additionally,the requirements established specific regulations for the use and storage of carcinogens. Except for arequirement that the top of a fume hood stack must be at least 7 feet above the roof, the regulations do notaddress emissions once the air from the fume hood mixes with outdoor air.

Yolo-Solano Air Quality Management District Regulations

The Campus is in Yolo and Solano Counties and is under the jurisdiction of the YSAQMD. TheYSAQMD regulates air quality through its permit authority over most types of stationary emission sourcesand through its planning and review activities. The YSAQMD is responsible for implementing emissionstandards and other requirements of federal and state laws.

As required by the California CAA, YSAQMD has published its 1991 AQAP. The AQAPaddresses the California CAA requirement to attempt to bring the SVAB into compliance with the federaland state ambient air quality standards. Because the SVAB is not in compliance with O3 standards, theAQAP addresses emissions of O3 precursors (volatile organic compounds [VOCs] and NOx). Currently,AQAPs are not required to address PM10, for which the YSAQMD is also a non-attainment area for thestate standards. In the AQAP, the YSAQMD indicates its intent to support measures that preserve andenhance the health and quality of life of its citizens. The AQAP includes carefully planned strategies forprogressive reduction of air pollutants by promoting active public involvement, by encouraging compliancethrough positive influence and behavior, and through public education in both the public and private sectors.

The AQAP does not forecast attainment of all federal and state ambient air quality standards bythe horizon year of 2010, primarily because of the substantial growth anticipated in Yolo and SolanoCounties between 1992 and 2010. The AQAP anticipates that the total emissions of O3 precursorpollutants will be reduced by the AQAP's control measures. However, the average annual percentagereduction of O3 precursors is anticipated to decrease over time as it is offset by the increases in O3

precursors resulting from population growth. Because the anticipated annual percentage reductions for O3

precursor pollutant emissions do not meet the required 5% reductions mandated by the California CAA,the AQAP states that the YSAQMD must include (and has included) all feasible reduction measures.



In the Campus area, the YSAQMD implements AB 2588 and is responsible for prioritizing facilitiesemitting air toxics. The purpose of AB 2588 is only to identify and evaluate risk from air toxics sources;AB 2588 does not regulate emissions of TACs. AB 2588 is generally considered risk-driven, information-oriented legislation.




n cause or contribute substantially to existing or projected violations of state or federal criteriaair pollutant standards;

n result in exposure of sensitive receptors to substantial pollutant concentrations; or

n result in exposure of sensitive receptors to unpleasant odors.

Estimating whether a project's criteria pollutant emissions would cause or contribute substantiallyto ambient air quality violations is most accurately evaluated through air quality modeling. However, forcertain pollutants and emission sources, air quality modeling is not feasible. In lieu of modeling, emissionthresholds are often used. If a project's emissions exceed one or more thresholds, the project is consideredto have a significant impact and should be mitigated to the extent feasible. In the YSAQMD, the emissionthresholds for criteria pollutants are assumed to equal the YSAQMD's emission offset requirementthresholds (Regulation III, Rule 3.4): 550 pounds per day of CO, and/or 82 pounds per day of ROG,NOx, oxides of sulfur (SOx), or PM10.

For toxic air contaminants, no ambient concentration standards or emission thresholds exist withwhich to evaluate the significance of the project's health risk. Consequently, the toxic air contaminantsignificance criteria are based on risk levels defined by state and federal agencies. For non-carcinogenic(chronic and acute) health risks, a change in the ground-level concentration of pollutants that exceeds ahazard index of 1.0 is considered significant. For carcinogenic health risks, any cancer risk exceeding 10in one million is considered significant.


Criteria Pollutants

As noted in the Revised Initial Study for the WWTP replacement project, short-term project-related construction activities would result in PM10 and O3 precursor emissions. The Revised Initial Studydescribes project-related emissions as incrementally contributing to PM10 emissions, which were identified


as a significant and unavoidable impact in the 1994 LRDP EIR. The 1994 LRDP EIR also states that O3

precursor emissions associated with construction are less than significant.

However, the Revised Initial Study also notes that the amount of project-related constructionactivity is not expected to be large and that project-related PM10 impacts could be mitigated to a less-than-significant level if, as anticipated, project construction does not occur in conjunction with many simultaneousprojects. The construction-related PM10 mitigation measures identified in the 1994 LRDP EIR have beenincorporated into the proposed project. These measures are described as Mitigation Measure 4.5-1 in the1994 LRDP EIR.

4.2-1 The proposed WWTP, during its operational phase, would generate 0.40 pound per dayand 145 pounds per year of ROG. This impact is considered less than significant.

The primary source of operational emissions would be the net increase in ROG generated by theproposed WWTP. Other potential sources of criteria pollutant emissions (especially ROG, NOx, and CO),such as employee commute trips and hauling of biosolids, would remain either the same or decrease. Appendix F provides an in-depth discussion of how these emissions were estimated. Total ROG emissionsproduced by the project are substantially lower than the significance thresholds and would not create asignificant air quality impact.


4.5-3(b) The Campus shall acquire permits for stationary and area sources asrequired by the Yolo-Solano Air Quality Management District.

As part of the permitting process for the proposed project, the YSAQMD will require the use ofthe best available control technology to minimize pollutant emissions. Compliance with 1994 LRDP EIRMitigation Measure 4.5-3(b) will reduce this impact to a less-than-significant level.

Mitigation Measure



4.2-2 The proposed WWTP, during its operational phase, would expose Campus occupants andDavis-area residents to toxic air contaminants emitted from the WWTP and other Campusemission sources. This impact is considered less than significant.

As part of the environmental analysis of the proposed project, the Campus updated the HRAcontained in the 1994 LRDP EIR to identify potential health risks associated with the WWTP replacementproject. These health risks included cancer risks and non-carcinogenic chronic and acute health risks. The


updated HRA uses ambient air toxics concentrations and risk/potency factors to estimate the number ofpotential cancer cases in the exposed population. The updated HRA also uses the ambient air toxicsconcentrations and acute and chronic health hazard indices to estimate the project's acute and chronic healthrisks. The updated HRA includes a comprehensive analysis of the dispersion of hazardous substances inthe environment, the potential for human exposure, and a quantitative assessment of both individual andpopulation-wide health risks associated with those levels of exposure. The calculated health risks are anapproximation of the reasonable worst-case health risk associated with the project. Appendix G includesthe updated HRA conducted for this project.

The updated HRA estimated the overall project-generated cancer risk to the maximally exposedindividual (MEI) to be 0.46 in a million. The MEI represents the location where an individual would beexposed to the highest concentration of toxic air contaminants from the WWTP and other Campusdevelopment. The individual(s) located at the MEI location is assumed to be exposed to the worst-caseproject emission concentration for a continuous 70-year period. The MEI location for cancer risk is at areceptor location just east of the relocated WWTP at the UCD border. Because the project's estimatedcancer risk is less than the significance standard of 10 in one million, the impact is considered less thansignificant.

The updated HRA also shows that the project's chronic and acute exposure hazard indices wouldboth be less than 1.0. The highest project-generated chronic hazard index was 0.0020, and the highestacute hazard index was 0.0093. The MEI for chronic exposure for total contemplated Campusdevelopment occurred at an on-Campus residential location, Pierce Hall, in the Central Campus. Thehighest acute hazard quotient for the total contemplated Campus development occurred at a point on thenorthern boundary of the Campus near Russell Boulevard. These low index values mean that the projectwould not be expected to cause any non-carcinogenic health effects. The project, therefore, would notpose a potential human health hazard and would not cause a significant adverse, non-carcinogenic healthimpact.

Mitigation Measure


Odors

4.2-3 The proposed project would relocate the existing WWTP, a known odor source, from theCentral Campus (a more densely populated area) to the South Campus (a less denselypopulated area). This impact is considered less than significant.

Odors can consist of several different pollutants. The primary source of odors at wastewatertreatment facilities is hydrogen sulfide produced by anaerobic organisms in septic collection systems or inanaerobic treatment processes at the facility site. Another common odor is nonionized ammonia, which is


prevalent and readily volatilized whenever wastewater pH is elevated. Finally, the solids storage basins(SSBs) throughout the year represent another potential source of odors.

Sensitive odor receptors near the existing WWTP site and the existing sludge drying ponds wouldexperience a reduction in exposure to odors associated with wastewater treatment operations. Theproposed WWTP is in an area with fewer sensitive receptors than the existing plant. Although the SSBsare designed to operate under anaerobic conditions, these conditions would only be maintained near thebottom half of the treatment basin. An aerobic water layer will be maintained in the upper portion of theSSB for odor control. (Appendix F includes an in-depth discussion of odor issues and the location ofsensitive odor receptors.)

For these reasons, the proposed WWTP and SSBs would not result in a significant impact tosensitive receptors located near the proposed project site.

Mitigation Measure



Criteria Pollutants

4.2-4 The proposed WWTP, in conjunction with 1994 LRDP development accommodated by theproposed project, would result in increased emissions of criteria pollutants. This impactis considered significant and unavoidable.

The 1994 LRDP EIR identified development associated with the LRDP as a significant andunavoidable impact because such development would cause violations of air quality standards andexceedances of the thresholds of significance for criteria air pollutant emissions. The following mitigationmeasures were identified to reduce the magnitude of this impact, but it would remain significant andunavoidable.

4.5-3(a) Implement 1994 LRDP EIR Mitigation Measures 4.3-1 and 4.3-5.

4.3-1(a) The Campus shall continue to actively pursue a program ofTransportation System Management (TSM) strategies to reduce relianceon travel to and from Campus by private automobile, particularly single-occupant peak period travel. As described in the Setting section, theCampus currently has an extensive TSM program. TSM strategiesinclude the development of a comprehensive bicycle circulation network,including a bicycle/pedestrian precinct in core area of Central Campus;increased parking fees; transit planning and subsidies; carpool andvanpool matching service, and development and incentive program;


campus shuttle systems, including shuttles to UC Davis Medical Centerin Sacramento and UC Berkeley, public awareness programs, park andride lot identification, and telecommuting.

4.3-1(b) In cooperation with other responsible jurisdictions, the Campus shallmonitor A.M. and P.M. peak hour traffic operations at criticalintersections in the Campus vicinity on a regular basis (at least everythree years). To the extent that TSM measures are successful, someroadway improvements may be avoided. Based upon the existingCampus mode share and trip generation rates assumed in this analysis,the following physical improvements are intended to reduce themagnitude of this impact.

(i) Reconstruct the intersection of Old Davis Road and CaliforniaAvenue. If the intersection remains at its current location, provideexclusive right turn lanes on each Old Davis Road approach andinstall a traffic signal. If the intersection is relocated to the south asshown on the LRDP, provide separate right and left turn lanes onthe California Avenue approach, and separate turn lanes on eachOld Davis Road approach and install a traffic signal.

(ii) n Convert the intersection of SR 113 Southbound Ramps andHutchison Drive to all-way stop control.

n Convert the intersection SR 113 Northbound Ramps andHutchison Drive to all-way stop control.

n Convert the intersection of Old Davis Road and I-80 WestboundRamps to all-way stop control.

n Convert the intersection of Old Davis Road and I-80 EastboundRamps to all-way stop control.

n Install a traffic signal at the intersection of D Street and FirstStreet.

n Install a traffic signal at the intersection of Road 98 and CovellBoulevard.

n Reconstruct the southbound Research Park Drive approach tothe intersection with Richards Boulevard/Cowell Boulevard toprovide a combined through left turn lane and a separateexclusive right turn lane.


n Add the following lanes at the intersection of I-80 EastboundRamps and Richards Boulevard to reduce the impact to the levelof service currently accepted by the City for the adjacentroadway for link from Olive Drive to First Street (LOS E):

- An additional turn lane on the ramp approach to theintersection, to provide a double left turn lane and a singleright turn lane; and

- An additional right turn lane along westbound RichardsBoulevard to the I-80 eastbound entrance ramp.

- Widening the Richards Boulevard Overcrossing of I-80 toprovide three westbound lanes; or

- Providing a new "slip" off-ramp from I-80 to provide threewestbound lanes; or

- Providing a new "loop" on ramp from Richards Boulevardeastbound to I-80 eastbound west of the existingovercrossing.

4.3-5 The Campus shall continue to support public transportation services, andwill work with the City and other agencies to implement increased transitservices in response to evolving campus needs. Such increased serviceswould include improved Unitrans terminal facilities to accommodateincreased ridership, developing new Unitrans routes and schedules tomore effectively serve travelers, and improved coordination with othertransit providers and modes of travel.

4.5-3(b) The Campus shall acquire permits for stationary and area sources asrequired by the Yolo-Solano Air Quality Management District.

Mitigation Measure


4.2-5 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, would result in increased emissions of criteria pollutants. Thisimpact is considered significant and unavoidable.


The 1994 LRDP EIR identified development associated with the LRDP as a significant andunavoidable impact because such development would cause violations of air quality standards andexceedances of the thresholds of significance for criteria air pollutant emissions. The following mitigationmeasures were identified to reduce the magnitude of this impact, but it would remain significant andunavoidable.

4.5-6(a) Implement Mitigation Measures 4.5-3(a) and (b).

4.5-6(b) The Sacramento Valley Air Basin includes a large number of jurisdictions,including the greater Sacramento metropolitan area. In the Basin, airquality is regulated by the Sacramento Metropolitan Air QualityManagement District, YSAQMD, and a number of other APCDs. Pursuant to rules, regulations, and policies of those AQMDs and APCDs,as well as adopted general plans throughout the Basin, it is within thejurisdiction of each local government or district to take actions to ensurecompliance with the federal CAA and the California CAA.

Yolo and Solano Counties are non-attainment areas for the state and federal O3 standards and statePM10 standards. The most recent air quality plan for the region, the Sacramento Area Regional OzoneAttainment Plan, does not project attainment with the federal O3 standard until 2005. Attainment withthe state O3 standard would likely not occur until several years after 2005. Buildout of the LRDP, whichincludes construction of a replacement WWTP, would contribute to the continued exceedance of air qualitystandards. Thus, the impact is considered significant and unavoidable.

Mitigation Measure



4.2-6 The proposed WWTP, in conjunction with 1994 LRDP development accommodated by theproposed project, will expose Campus occupants and Davis area residents to toxic aircontaminants emitted from uses on Campus. This impact is considered less thansignificant.

The updated HRA prepared for the proposed project indicates that the cancer risk associated withdevelopment allowed under the 1994 LRDP, and as accommodated by the proposed WWTP, equals 0.46in one million. The standard of significance is 10 in one million. Similarly, the acute and chronic health risksassociated with cumulative Campus-wide development are substantially less than the significance thresholds. Thus, the Campus contribution to toxic air contaminant emissions would contribute only minimally to anycumulative significant health effect.


Mitigation Measure


4.2-7 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, may generate unacceptable cumulative toxic air contaminant healthrisks. Inadequate methods exist to assess the magnitude of this impact, and it is thereforeconsidered too speculative to determine the precise level of significance. This impact isconsidered significant and unavoidable.

The 1994 LRDP identified unacceptable cumulative toxic air contaminant health risks as asignificant and unavoidable impact.

The updated HRA prepared for the proposed project indicates that the cancer risk associated withdevelopment allowed under the 1994 LRDP, and as accommodated by the proposed WWTP, equals 0.46in one million. The standard of significance is 10 in one million. Similarly, the acute and chronic health risksassociated with cumulative Campus-wide development are substantially less than the significance thresholds. Thus, the Campus contribution to toxic air contaminant emissions would contribute only minimally to anycumulative significant health effect.

However, the cumulative contribution for toxic air contaminants in the Campus vicinity includesother stationary sources and mobile sources operating on nearby roads. No acceptable methodologycurrently exists to assess toxic air contaminants from mobile sources, or to cumulatively assess the combinedeffects of mobile and stationary sources of air toxics. Section 15145 of the CEQA Guidelines states thatwhen an impact is too speculative for evaluation, it is appropriate to note this conclusion. Because theimpact is too speculative to evaluate, it is designated as significant and unavoidable to represent the mostconservative approach.

Mitigation Measure

4.2-7 No feasible mitigation has been identified.


Chapter 4.3 Hazardous Materials and Public Safety

INTRODUCTION

This chapter addresses impacts of the project on issues related to hazardous materials and publichealth. Chapter 4.1, “Hydrology and Water Quality”, contains an evaluation of water resource and waterquality issues related to the project.

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), thisanalysis focuses on the potential impacts related to radioactive materials and waste, and biohazardousmaterials and waste. Hazardous waste issues related to the completion of due diligence requirements forthe existing and proposed WWTP sites are also addressed. Potential impacts related to human exposureto existing contamination during construction or demolition activities, increased use of hazardous chemicalsand disposal of hazardous waste, increased use of laboratory animals, increased transportation of hazardousmaterials, availability of emergency response services, and increased fire hazard were adequately addressedby the 1994 LRDP EIR.

The 1994 LRDP EIR defines the terms “hazardous waste”, “radioactive materials”, and“biohazardous materials”. These definitions are also applicable to the analysis in this section and areincorporated herein by reference. These issue areas are discussed individually below under “EnvironmentalSetting”.


Hazardous Waste

This section presents information on the potential presence of hazardous wastes obtained from the1994 LRDP for the existing WWTP and the completion of a “due diligence checklist” to evaluate thepotential for contamination associated with the proposed WWTP site and pipe routes, and areas of knownor suspected contamination at the existing WWTP site.


The project consists of decommissioning and completely or partially demolishing the existingWWTP, decommissioning and demolishing the sludge drying ponds, and constructing the proposed WWTPand influent and effluent pipelines. The 1994 LRDP identifies several areas requiring further investigationfor soil and groundwater contamination, including the existing sludge drying ponds. The 1994 LRDP EIRevaluates health and safety effects related to developing potentially contaminated sites and demolishingstructures that could contain contaminated building materials.

The due diligence checklist for the proposed WWTP site, which was completed on August 1,1996, indicated no observations of environmental contamination or evidence of past activities that wouldbe suspected of having a significant adverse impact on the site. The checklist concluded that there wereno environmental issues or conditions that would prohibit the University from proceeding with the proposedproject. Copies of this report are available for review during normal office hours at the UC Davis Officeof Architects & Engineers and is hereby incorporated by reference.

Radioactive Materials

This section addresses the disposal of low-level radioactive liquids to the sanitary sewer, as allowedby Campus policy and in accordance with applicable federal and state regulations. The use, handling, anddisposal of solid radioactive materials were adequately addressed in the 1994 LRDP EIR. No radioactivematerials are used in the operation and maintenance of the existing WWTP. The disposal of low-levelradioactive liquids was addressed in the Campus local limits development process, as part of thepretreatment program (Appendix E). Radionuclides were not included in the local limits because they arealready covered by existing regulations and Campus policy and procedures. The Campus policy andregulations for (handling and disposal of) radioactive materials are discussed below under “RegulatorySetting”.

Environmental Services Facility staff follow a detailed procedure on the handling of low-levelradioactive liquids to ensure that the Campus policy is fully implemented and in compliance with theapplicable regulations. The quantity of low-level radioactive liquids released to the sewer system in any onemonth is not allowed to result in an average concentration exceeding specified regulatory effluentconcentration limits. Campus policy is not to exceed 50% of these release limits (see “Regulatory Setting”below). A summary of radiological sanitary sewer disposal data from 1991-1995 is presented in Table4.3-1. The allowable annual limits are 5,000 millicuries (mCi) for tritium, 1,000 mCi for carbon-14, and1,000 mCi for all other radionuclides. The data indicate that the Campus disposes of between 1% and28% of the regulated disposal limit (Westcott pers. comm.).

As part of the ongoing investigation of the LEHR facility, surface water samples have been collectedat two locations in the South Fork of Putah Creek and the existing WWTP outfall on a quarterly basis since1990. The samples have been analyzed for a wide variety of conventional and toxic pollutants and forradionuclides, including gross-alpha and beta, radium-226, strontium-90, and tritium. A review of datacollected indicated that no results exceeded the maximum contaminant levels in state drinking water


standards. The results were well below the effluent concentration release limits and, in most cases, belowthe laboratory minimum detection limit (Westcott pers. comm.).


Table 4.3-1. Summary of Radiological Waste Sanitary Sewer Disposal Data: 1991-1995

1991 1992 1993 1994 1995

Tritium

Allowable limit 5,000 mCi 5,000 mCi 5,000 mCi 5,000 mCi 5,000 mCi

Total disposed 111.75 mCi 296.81 mCi 149.96 mCi 85.52 mCi 127.35 mCi

% of allowable limit 2.2% 5.9% 3% 1.7% 2.5%

Carbon-14



% of allowable limit 1.8% 6.3% 4.3% 3.3% 1.1%

All Other Radionuclides



% of allowable limit 3.3% 23.3% 13.7% 18.5% 27.5%

Note: mCi = millicuries

Source: Westcott pers. comm.


Biohazardous Materials

Background

The 1994 LRDP EIR addressed the use of biohazardous materials and wastes in a variety ofCampus research activities. These activities use a variety of potentially biohazardous substances, such asrecombinant DNA molecules, infectious agents, parasites, and other biological agents. For the purposesof this analysis, biohazardous materials include any of the research materials that are discarded, such asinfected items, laboratory wastes, medical wastes, infected animal carcasses and feces from researchanimals, and wastes from any infected humans in the Campus human population.

This analysis focuses on the potential discharge of biohazardous materials to the sewer and inWWTP effluent. Wastewater itself is not considered a biohazardous material by state and federalregulations. The infectious agents of primary concern in biohazardous materials include viral pathogens,bacterial pathogens, protozoan parasites, and helminth parasites. Potential sources include infected humansusing Campus toilets that would contribute these agents to untreated wastewater; in addition, other potentialCampus sources of these agents include the California Regional Primate Research Center (CRPRC), theVeterinary Medical Teaching Hospital, and the Medical Sciences I Complex. The use of biohazardousmaterials at these facilities was addressed in the 1994 LRDP EIR.

A concern related to sewer discharges from the CRPRC is the potential transmission of humanimmunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). The CRPRC now discharges tothe existing WWTP via the West Campus wastewater connection. Infected wastes and equipment at theCRPRC are disinfected and autoclaved prior to discharge. Animal cages are hosed daily with a disinfectantsolution, and indoor cages are sanitized every two weeks at the CRPRC’s cage washing facility. Sewagewaste from the facility consists of urine, feces, and occasional menstrual blood in disinfectant solution. Thepresence or lack of virus and/or bacteria in this effluent is based on the organism’s survivability through cagewashing with disinfectant. The facility meets or exceeds all established state and federal procedures forhandling wastes. Detailed descriptions of the use and disposal procedures at the CRPRC are presentedin the California Regional Primate Research Center Expansion EIR (University of California, Davis1993a) and the West Campus Wastewater System Connection EIR (University of California, Davis1993b). Copies of these reports are available for review during normal office hours at the UC Davis Officeof Architects & Engineers and are hereby incorporated by reference.

Discussion of Potential Biohazardous Materials in Wastewater and Their Environmental Fate

This section presents background information on the infectious agents potentially present inuntreated wastewater and WWTP effluent and aspects of their environmental fate related to the potentialfor human exposure from the WWTP discharge to the South Fork of Putah Creek. The information is asfollows:


n general description of waterborne infectious agents,n discussion of potential infectious agents in untreated wastewater and WWTP effluent,n discussion of environmental fate, andn discussion of routes of exposure and infective dose.

General Description of Common Waterborne Infectious Agents. The most commonwaterborne infectious agents are of intestinal origin and are discharged to the sewer system primarily inhuman and animal feces. Tissue or blood disposed to the sewer system could be a source of bloodbornepathogens. The organisms are broadly classified in four groups: viruses, bacteria, protozoa, and helminths. Table 4.3-2 presents a summary of the most common waterborne infectious agents. In addition, a briefdescription of the characteristics of the various categories of microbial agents is provided below.

Viral Pathogens . Because viruses are obligate intracellular parasites (i.e., they have nocell structure of their own), they are incapable of replication outside a host organism. They range in size fromapproximately 25 nanometers (nm) to 350 nm and therefore can only be observed with an electronmicroscope. Enteric viruses replicate in the human intestinal track and are shed in fecal material of infectedindividuals. There are more than 100 different known human enteric viruses. HIV (and other similarviruses, such as SIV) is not shed in the feces of infected individuals. Its only means of getting intowastewater is by mixing of water with blood, semen, saliva, or tears prior to entering the sewer system. Because HIV is a bloodborne disease, the Centers for Disease Control does not consider the waterborneroute via wastewater a possibility for transmission (Gover 1993).

A recent report on HIV exposure categories did not implicate environmental sources of any type(Mortality and Morbidity Weekly Report 1995). This information indicated that environmental sources suchas wastewater are not considered a potential source of infection for HIV. There is also no evidence thatwastewater workers have any demonstrable adverse effects from HIV or other more virulent infectiousagents (Mortality and Morbidity Weekly Report 1995). The Centers for Disease Control does notconsider the waterborne route a possibility for HIV transmission (Gover 1993) and permits the disposalof human waste from HIV-infected individuals into municipal sewage treatment systems (University ofCalifornia, Davis 1993a). In summary, the results of this review agreed with the findings presented in theCalifornia Regional Primate Research Center Expansion EIR (University of California, Davis 1993a)and the West Campus Wastewater System Connection EIR (University of California, Davis 1993b). Assuming the continued implementation and enforcement of correct disinfection and waste disposalprocedures and adequate wastewater treatment, based on the studies and data cited, the public health riskfrom HIV and other similar viruses from the proposed WWTP effluent is virtually nonexistent.

Bacterial Pathogens . Bacteria are microscopic organisms that range in size from 0.2micrometers (µm) to 10 µm. Fecal material contains many types of harmless bacteria that colonize thehuman intestinal tract. Fecal matter contains up to 1012 bacteria per gram. The coliform group of intestinalbacteria has historically been used as an indicator of environmental pollution by wastewater and ofwastewater effluent disinfection performance. As shown in Table 4.3-2, other important bacteria may bepresent in human feces that are both pathogenic to humans and transmittable by the waterborne route.Table 4.3-2


Table 4.3-2. Major Waterborne Human Infectious Agents

Organism Major Disease

Bacteria

Salmonella spp. Typhoid, paratyphoid

Shigella bacillary dysentery

Vibrio cholerae cholera

Enteropathogenic E. coli gastroenteritis

Yersinia enterocolitica gastroenteritis

Enteric Viruses

Enteroviruses (Polio-, Coxsackie-Aand B, Echo-, Hepatitis A)

paralysis, meningitis, respiratory illness,myocarditis, gastroenteritis, infectioushepatitis

Rotavirus gastroenteritis

Adenovirus respiratory illness, gastroenteritis

Norwalk agent gastroenteritis

Astrovirus gastroenteritis

Protozoa

Giardia lamblia diarrhea

Entamoeba histolytica amoebic dysentery

Cryptosporidium diarrhea

Helminths

Ascaris lumbricoides (roundworm) intestinal obstruction

Necator americanus (hookworm) hookworm disease (gastrointestinaltract)

Sources: Feachem et al. 1983, Bitton 1994.


Protozoan Parasites. Most protozoan parasites produce cysts/oocysts (i.e., restingstage) that can survive outside their host under adverse environmental conditions. In general, protozoanparasitic cysts are larger than bacteria. They range in size from 2 µm to 15 µm. Both symptomatic andnonsymptomatic individuals excrete protozoan cysts/oocysts. Protozoan parasites are similar in nature toviruses in that they do not reproduce outside the host organism (i.e., in the environment). Table 4.3-2shows the major waterborne protozoan parasites affecting humans.

Helminth Parasites. Table 4.3-2 shows the most common pathogenic helminths. The ovaconstitute the infective stage of parasitic helminths and are particularly resistant to environmental factors. Helminthic eggs and cysts tend to range in size from 5 µm to 150 µm and can have varying shapes, suchas spherical and cylindrical. Helminthic infections are common primarily in developing countries and tendto be closely related to economic status. Transmission of helminthic infections tends to be through contactwith contaminated soil and food. Many helminthic infections require an intermediate animal host. Successfulcontrol of helminthic infections can be directly correlated with eradication of the intermediate host, healtheducation, provision of toilets, and the proper treatment and disposal of wastewater sludge.

Potential Infectious Agents in Untreated Wastewater. Wastewater treatment plants are notrequired by the Regional Water Quality Control Board (RWQCB) or by the California Department ofHealth Services (DHS) to monitor for potential infectious agents in untreated or treated wastewater. Monitoring is required, however, for indicator organisms, such as total or fecal coliform organisms. Accordingly, actual data were not available on the presence of infectious agents contained in biohazardousmaterials discharged in untreated wastewater at the existing WWTP. This discussion concerns keyinfectious agents that could potentially be present.

The occurrence and concentration of infectious agents in untreated wastewater from the existing andproposed WWTPs will vary over time because of differences in the prevalence and incidence rates of illnesswithin the Campus human population. The nature and quantity of other discharges to the sanitary sewer thatcontain human and animal waste will also affect the occurrence and concentration of infectious agents. Inaddition, the nature and quantity of the domestic and wild animal population in the Putah Creek drainagearea will affect the concentration of potential pathogens in the receiving water. The most common infectiousagents of potential concern in untreated wastewater are enteric viruses, Salmonella spp., Giardia lamblia,and Cryptosporidium spp. A summary of these pathogens is provided below.

Viruses. Reported estimates of viruses in untreated wastewater are approximately 100particle forming units per liter (pfu/L) (Rao and Melnick 1986). Although substantial progress has beenmade in the ability to detect viruses in untreated wastewater, effluent, and surface waters, it has beenreported that the efficiency of these methods averages less than 20% and the precision is low (Rao andMelnick 1986). Therefore, the concentration of viruses in untreated wastewater could be at least 10 timesgreater than the reported estimates, or approximately 1,000 pfu/L.

Bacterial Pathogens . Salmonellae are the most predominant pathogenic bacteria inwastewater, with concentrations reported to range from a few to 8,000 organisms/L (Feachem et al.1983).


Protozoan Parasites. A survey of untreated wastewater in the United States indicatedthat Giardia cyst concentrations varied from hundreds to thousands of cysts per liter. One report evenshows concentrations of 105 cysts/L (Rao and Melnick 1986). Cryptosporidium spp. oocysts have beenreported at concentrations between 850 and 13,700 oocysts/L in untreated wastewater (Rao and Melnick1986).

Existing WWTP Treated Effluent. As noted above, there were no data available on the actuallevels of these biohazardous materials in treated effluent at the existing WWTP. The WWTP effluent istreated to a standard of 23 MPN/100 ml (most probable number per 100 milliliters), which is the currentregulatory level established by RWQCB as safe for discharge to the South Fork of Putah Creek. Theexisting WWTP effluent has consistently been below this level overall since 1990, and was below8 MPN/100 ml in 1995 (see Chapter 4.1, “Hydrology and Water Quality”).

Discussion of Environmental Fate. If an infectious agent is to spread, a dose large enough tocause infection (i.e., infective dose) must be ingested by a susceptible host. This transmission depends ona number of factors, including the original load of pathogens in the untreated wastewater, the efficiency andreliability of wastewater treatment processes, changes resulting from environmental factors, and the doserequired to infect an individual. Three basic factors tend to govern the dose: persistence, latency, andmultiplication.

Persistence. Persistence is a measure of a microorganism’s ability to survive in theexternal environment. Survival rates can vary widely depending upon the biological nature of the pathogenand the nature of the environmental conditions, such as temperature, light, predation, and competition. Onemeasure of the survival rate used in the water industry is the “T90” value. This is not a regulatory standardbut an estimate of the time in minutes that it would take for organisms to die off (or be reduced in infectivity)by 90%. Examples of comparative survival rates of selected pathogens in surface water are as follows:

Pathogen Survival Rate (T90)a

Salmonella spp. 19-80

Vibrio cholerae 31

Poliovirus 25

Giardia muris cystb 360-1272a Time in minutes to reduce numbers or infectivity by 90 percent.b Based on loss of infectivity.Sources: Bitton 1994; DeRignier 1989.

Persistence through various wastewater treatment processes can also vary, particularly with regard to theeffectiveness of disinfection. The value known as the “CT” product is used in the water treatment industry


as a measure of the effectiveness of disinfection; the CT is the product of the time in minutes that the wateris in contact with the disinfectant, chlorine, multiplied by the concentration of chlorine present, in milligramsper liter (mg/L) in units of mg/L-minutes (i.e., higher CT values mean greater persistence given an equalchlorine level and contact time). Examples of this variation can be seen in CT values assigned tochlorination effectiveness in reducing the concentration of enteric viruses and Giardia cysts.

Pathogen CT99.9a

Enteric Viruses 4

Giardia cysts 112a CT equals the chlorine residual concentration in mg/L multiplied by the contact time in

minutes to achieve a 99.9% pathogen reduction at a pH of 7.0 and atemperature of 10°C.

Source: U.S. Environmental Protection Agency 1991.

The table shows that a considerably higher chlorine dosage and/or contact time is necessary asindicated by the higher CT value of 112 that is required to kill or inactivate 99.9% of any Giardia present(i.e., the higher the number, the harder to kill or inactivate). Enteric viruses, in contrast, with a CT of only4, are much less resistant to disinfection and, therefore, less persistent than Giardia cysts.

In the wastewater treatment industry, disinfection effectiveness is measured by the number of totalcoliform organisms present after treatment. Coliforms are not pathogens but are widely used as indicatororganisms for the presence of pathogens. Disinfection can be accomplished using either chlorine orultraviolet (UV) radiation. UV disinfection is becoming more widespread given the potential hazards fromstorage and use of chlorine compounds. UV has been selected as the method of disinfection for theproposed WWTP because it can reliably meet the anticipated effluent coliform standards. DHS acceptsUV as equivalent to chlorination for the Title 22 wastewater reclamation criteria as long as it conforms tothe National Water Research Institute guidance in this area (Hultquist pers. comm.).

The proposed WWTP would use a UV disinfection system designed to produce an effluent meetingthe anticipated National Pollutant Discharge Elimination System (NPDES) permit disinfection standards ofa 7-day median of 2.2 MPN/100ml and a maximum of 23 MPN/100ml for coliform organisms (seeChapter 3, “Project Description”). The other potentially applicable regulation would be the California Codeof Regulations Title 22 standards for tertiary recycled water suitable for unrestricted reuse, which similarlyrequires a 2.2 MPN/100ml 7-day median for total coliform organisms. Thus, the anticipated NPDESpermit disinfection standard of 2.2 MPN/100ml is based on the Title 22 disinfection standard. Title 22standards also set limits for turbidity that specify that treated effluent must not exceed:

n 2 nephelometric turbidity units (NTU) average turbidity,


n 5 NTU more than 5% of the time, andn 10 NTU at any time.

The proposed WWTP is not required to meet the Title 22 standards because the treated effluentis not being proposed for use as tertiary recycled water suitable for unrestricted reuse. Nonetheless, theanticipated NPDES permit standards to which the proposed WWTP is being designed are equivalent tothe most stringent Title 22 coliform standards for disinfection. The proposed WWTP occasionally mayexceed the most restrictive Title 22 standard of 2 NTU and might not fully conform with the Title 22standard for turbidity on rare occasions when peak wet-weather flow conditions and routine maintenanceof the filters are being performed at the same time; filter maintenance is typically performed weekly and iscompleted in less than one hour. Even then, the potential exceedance of the turbidity of the treated effluentover the Title 22 standard would be minor, and, because of the conservative design of the UV disinfectionsystem, the NPDES permit disinfection standard of 2.2 MPN/100ml would still be met.

This system would also be equipped with alarms that would alert the operator if the turbidity levelis too high. Thus, except for these extremely limited times, the proposed WWTP would produce an effluentequivalent in quality to the Title 22 disinfected tertiary recycled water, which is suitable for unrestricted reuseand considered safe for full body contact recreation (e.g., swimming). If a brief exceedance of the morerestrictive Title 22 turbidity standard did occur, it would be in wet-weather conditions when the turbidityin the South Fork of Putah Creek is likely to be substantially higher than that of the WWTP discharge in anyevent.

Persistence of viral and bacterial pathogens in surface water is similar, but the cysts of protozoanparasites are considerably more resistant to decay in the aquatic environment. In most treatment processes,the bacteria and viruses are removed to about the same degree, the exception being that many entericviruses are more resistant to the effects of disinfection than are the bacterial agents of concern. The cystsand oocysts of protozoan parasites may be orders of magnitude more resistant than viruses.

Multiplication. Under favorable conditions, certain pathogens can multiply in theenvironment. Certain bacterial pathogens are able to multiply in a favorable environment such as food;however, multiplication in water and wastewater is rare. Excreted viruses and protozoa (i.e., Giardia spp.and Cryptosporidium spp.) do not multiply outside their animal host.

Latency. For the purposes of this assessment, latency is the interval between the excretionof a pathogen and its becoming infective to a new host. Some organisms, including excreted viruses,bacteria, and protozoa, have no latent period and are immediately infective in untreated wastewater.

Discussion of Potential Exposure and Infective Dose. A necessary component of any publichealth evaluation involves identifying the route of exposure and the dose of pathogenic organisms that asusceptible individual could consume. A general description of the exposure route and dose associated withthe existing WWTP is presented below.

Route of Exposure . The assumed route of exposure for the existing and proposedWWTPs is through recreational contact with water in the South Fork of Putah Creek and direct ingestion


through consumption of the surface water containing the treated wastewater. This exposure could occurunder summer conditions, when minimal or no dilution of the treated wastewater occurs because the primaryand sometimes sole source of flow in this reach of the creek is from the existing WWTP.

Dose. The U.S. Environmental Protection Agency (EPA) has estimated that swimmersand waders may ingest 0.3-1.7 ounces (approximately 9-50 ml) of water per outing and have estimatedthat the national average for swimming is seven days per year (U.S. Environmental Protection Agency1993). The estimated dose of organisms that could be consumed per swimming event, based on theseassumptions, is shown in Table 4.3-3.

Minimal Infective Dose. The minimal infective dose (MID) has been reported to varywidely with the type of pathogen. For example, for Salmonella spp. or enteropathogenic E. coli,thousands to millions of organisms are necessary to establish illness, while for Shigella, the MID can be aslow as 10 organisms. A summary of the MID for pathogens selected because they are the most commonwaterborne sources of human illness is shown in Table 4.3-4.

REGULATORY SETTING

Hazardous Waste

The regulatory requirements for the management of hazardous wastes, including those relevant todue diligence requirements, were addressed in Appendix E of the 1994 LRDP EIR.


Campus Low-Level Radioactive Liquid Disposal Policy

This policy pertains specifically to the disposal of low-level radioactive liquids to the sanitary sewer(Westcott pers. comm.). The Campus Office of Environmental Health and Safety (EH&S) will dispose orsupervise the disposal of low-level radioactive liquid wastes meeting the following required criteria:

1. The liquid must be readily soluble or dispersible in water. An industrial hygienist or chemist willbe consulted on the suitability of sewage disposal for all liquids other than water, urine, andfeces based on the chemical content listed on the label. All outside consultation must bedocumented with disposal records.


Table 4.3-3. Estimated Dose of Pathogens Consumed per Swimming Event

Enteric Viruses(pfu/L)

Salmonella spp.(organisms/L)

Cryptosporidiumspp. (oocysts/L)

Giardia spp.(cysts/L)

Concentration intreated wastewater

0.2-0.00001 0.8-0.00008 low: 1.5-150high: 0.0001-0.01

low: 1.5-1,500high: 0.0001-0.01

Number of organismsconsumed per event a

0.006-3x10-7 2x10-7-2x110-6 low: 0.045-4.5high: 3x10-4-3x10-6

low: 0.045-45high: 3x10-3-3x10-6

Notes: Low based on worst-case removal from Table 4.3-5.High based on best-case removal from Table 4.3-5.a based on average water consumption of 30 ml.

Sources: Feachem et al. 1983, Rowe and Abdel-Magid 1995, Yates n.d., Bitton 1994.

Table 4.3-4. Summary of the Minimal Infective Dose for Selected Organisms

Organism Infective Dose(no. of organisms)

Infective Rate a

(percent, %)Minimum Dose b

(no. of organisms)

Salmonella spp. 105-108 50% 105

Shigella spp. 101-102 50% 101

E. coli c 106-1010 25%-75% 106

Enteric viruses d < 102 50% < 102

Giardia lamblia 1-100 50% < 10

Cryptosporidium 1-100 50% < 10

a Percentage of individuals receiving dose who became infected or diseased. b Minimum number of organisms required to produce disease. c Includes enterotoxigenic, enteroinvasive, and enteropathogenic E. coli. d Response is infection, not disease; units are pfu.

Sources: Feachem et al. 1983, Rowe and Abdel-Magid 1995, Bitton 1994.


2. The quantity of any radioactive material released in any one month, if diluted by the averagemonthly quantity of sewage released, will not result in an average concentration exceeding thelimits specified in 10 Code of Federal Regulations (CFR) 20, Sections 20.1001-20.2401,Appendix B (Campus policy is to not exceed 50% of these limits).

3. The fractional monthly limit of discharges into the sanitary sewer must be determined by dividingthe actual monthly average concentration of each radionuclide released into the sewage by theconcentration limit (10 CFR 20, Appendix B), and must be less than one.

4. The combined total quantity of radioactive material released into the sewer system for theCampus will not exceed five curies of tritium (H3), one curie of carbon 14 (C14), and one curieof all other radionuclides combined per year.

5. Excreta from individuals on Campus undergoing medical diagnosis or therapy with radioactivematerials will be exempt from any limitations contained in California Radiation ControlRegulations, Title 17, Section 30287.

6. Campus users are not permitted to dispose of radioactive materials in laboratory sinks. EH&Swill dispose of some materials into the sewer system at the Environmental Services Facility.

7. The Environmental Services Facility personnel will maintain a monthly sewer disposal logindicating the microcurie quantity by radionuclide for all sewer disposal. Records will includedaily and monthly totals for each radionuclide, cumulative totals for all radionuclides for the yearto date, daily and monthly fractions of the specified limits, and documentation of noncomplianceissues found.

8. All short-lived radionuclides (i.e., half-lives less than 90 days) are decayed for at least sevenhalf-lives and, in many cases, twelve half-lives in order to reduce the amount of low-levelradioactive waste being disposed of to the sanitary sewer system.


The U.S. Department of Health and Human Services Public Health Service, Centers for DiseaseControl and Prevention, and National Institutes of Health prescribe containment and handling principles foruse in microbiological and biomedical laboratories and animal facilities. Although following these guidelinesis not legally required for most activities, all Campus laboratories operate with the intent of following thesegood hygienic practices. Campus researchers are required to obtain authorization to use biohazardousagents prior to their use.

The California Medical Waste Management Act of 1990 also addresses biohazardous wastehandling requirements.


Regulations relevant to potential infectious agents that could be present in WWTP effluent areaddressed in California Code of Regulations, Title 22, Division 4, Chapter 3; the intent of these regulationsis to protect human health. These regulations specify levels of treatment and disinfection required to producean effluent deemed safe for a variety of uses and activities and are not meant to be limits for individualpathogens. These regulations are also addressed in Chapter 4.1, “Hydrology and Water Quality”, under“Regulatory Setting”.



As stated in the 1994 LRDP EIR, an impact is considered significant if the proposed project would:

n create a substantial potential health or safety hazard associated with risk of upset (accidents);

n involve the use, production, or disposal of materials in a manner that poses a hazard to people,or to animal or plant populations in the area affected;

n expose employees to working situations that exceed health standards; or

n violate applicable laws intended to protect human health and safety.


Hazardous Waste

4.3-1 Construction activities associated with the proposed project could expose Campusoccupants and construction workers to contaminated soil or groundwater. This impact isconsidered potentially significant.


4.6-16(a) During the site selection process for each site to be developed under the1994 LRDP, the Campus shall determine the need to have the site andadjacent areas investigated for the presence of hazardous materials orwastes by completing a “due diligence checklist”.


If further investigation is warranted, the investigation shall be carried outby a registered environmental assessor (i.e., a professional environmentalscientist or engineer registered in California) or a registered engineer. The investigations shall be environmental audits, which shall include, ata minimum, site inspections for hazardous materials, examination ofhistorical records for evidence of hazardous materials use, interviewswith Campus personnel, and review of Campus records for evidence ofcontamination.

For each site audit, the qualified person shall prepare a report detailingthe results of the inspection and submit it to appropriate Campus offices. The report preparer shall certify that the site is free of hazards,recommend further investigations, or recommend preparing a sitemitigation plan. After reviewing and accepting the report, reviewingoffices shall submit it to the Planning and Budget Office (the officeresponsible for site selection and environmental review on Campus) withtheir recommendations. The Campus shall ensure that inspection reportsare completed prior to excavation or construction at the developmentsite.

4.6-16(b) In the event that site inspections find evidence of chemical or radioactivecontamination, waste discharges, underground storage tanks, abandoneddrums, or other environmental impairment at locations to be developedor in the project area, the Campus shall prepare a site remediation planthat shall (1) specify measures to be taken to protect workers and thepublic from exposure to potential site hazards and (2) certify that theproposed remediation measures would clean up the contaminants,dispose of the wastes, and protect public health in accordance withfederal, state, and local requirements. Commencement of work in theareas of potential hazard shall not proceed until the site remediation planhas been completed. Depending on the nature of any contamination,appropriate agencies shall be notified (e.g., the CVRWQCB forgroundwater contamination and the DTSC for soil contamination [or theappropriate County Environmental Health Department]). Provisions ofthe site remediation plan would be adopted by the Campus as part offuture projects.

4.6-16(c) A site health and safety plan, in compliance with OSHA requirements,shall be developed by the Campus and in place prior to commencingwork on any contaminated sites.

In compliance with 1994 LRDP Mitigation Measure 4.6-16, the Campus completed a “duediligence checklist” to determine the need to have the project site and adjacent areas investigated for the


presence of hazardous materials or wastes. In accordance with this mitigation measure, an investigation ofthe proposed WWTP site and influent and effluent pipelines was completed by a representative of EH&S. No evidence of contaminated soil or groundwater was identified and no additional studies have beenrecommended. Therefore, this potential impact has been mitigated to a less-than-significant level.

Mitigation Measure


4.3-2 The demolition or renovation of structures at the existing WWTP could expose Campusoccupants and construction workers to contaminated building materials. This impact isconsidered potentially significant.

The 1994 LRDP EIR identified the following mitigation measures that apply to the project.

4.6-18(a) During the site selection process for each site to be developed under the1994 LRDP, the Campus shall determine the need to have existingbuildings on each site investigated for the presence of hazardousmaterials or wastes by completing a “due diligence checklist”.

If further investigation is warranted, the investigation shall be carried outby a Registered Environmental Assessor (i.e., a professional en-vironmental scientist or engineer registered in California) or a registeredengineer. The investigations shall be environmental audits, which shallinclude, at a minimum, site inspections for hazardous materials,examination of historic records for evidence of hazardous materials,examination of historic records for evidence of hazardous materials use,interviews with Campus personnel, and review of Campus records forevidence of contamination.

For each site audit, the qualified person shall prepare a report detailingthe results of the inspection and submit it to appropriate Campus offices. The report preparer shall either certify that the site is free of hazards,recommend further investigations, or recommend preparing a sitemitigation plan. After reviewing and accepting the report, reviewingoffices shall submit it to the Planning and Budget Office (the officeresponsible for site selection and environmental review on Campus) withtheir recommendations. The Campus shall ensure that inspection reportsare completed prior to excavation or construction at the developmentsite.

4.6-18(b) In the event that site inspections find evidence of chemical or radioactivecontamination in buildings at sites to be developed, the Campus shall


prepare a site remediation plan that shall (1) specify measures to betaken to protect workers and the public from exposure to potential sitehazards and (2) certify that the proposed remediation measures wouldclean up the contaminants, dispose of the wastes, and protect publichealth in accordance with federal, state, and local requirements. Commencement of work in the areas of potential hazard shall notproceed until the site remediation plan has been completed. Dependingon the nature of any contamination, appropriate governmental agenciesshall be notified. Provisions of the site remediation plan would beadopted by the Campus as part of future projects.


The existing structures at the WWTP could contain asbestos, polychlorinated biphenyls (PCBs),or other hazardous materials that could cause adverse health impacts if human exposure is permitted duringdemolition or renovation.

In compliance with 1994 LRDP EIR Mitigation Measure 4.6-18, after the existing WWTP isdecommissioned, the Campus will complete a “due diligence checklist” for buildings at the existing WWTPsite. Therefore, this potential impact has been mitigated to a less-than-significant level.

Mitigation Measure



4.3-3 Disposal of low-level radioactive liquids in untreated wastewater and WWTP effluentcould pose a potential risk to public health and the environment. This impact isconsidered potentially significant.

The information summarized below pertains to the existing WWTP but also applies to the proposedWWTP because the conditions of disposal of low-level radioactive liquids to the sewer are not expectedto change.

The disposal of low-level radioactive liquid wastes to the sanitary sewer is allowed by state andfederal laws up to specified annual quantities and monthly effluent concentration limits, and is controlled byCampus policy. Campus Environmental Services Facility staff follow a detailed procedure to ensure thatthe disposal will not exceed the Campus guideline of 50% of the allowable limits (Table 4.3-1). Data from1991-1995 indicate that the disposal is well below the allowable release limits. Data collected from


WWTP effluent for the past five years have indicated that radionuclide concentrations are well below theapplicable maximum effluent concentration limits.

In addition, the Campus has been working to implement the mitigation measure identified in the1994 LRDP, which would further reduce the potential for this impact.


4.6-6(a) The Campus shall complete and occupy the proposed EnvironmentalServices Facility and close the current Environmental Services Facility.

or

4.6-6(b) The Campus shall manage radioactive waste generated by projectsapproved under the 1994 LRDP through a non-Campus facility. Thesefuture wastes shall not be taken to the existing hazardous wasteaccumulation facility. Instead, after the wastes are collected by EH&S,an outside contractor shall pick up the wastes from the loading docks ofthe buildings where the waste is produced and the contractor shall handledisposal.

and

4.6-6(c) Implement Mitigation Measure 4.6-1(a), which would require the Campusto create a Waste Minimization Coordinator position to implement theCampus Hazardous Waste Minimization Plan.

and

4.6-6(d) The Campus shall prepare and implement a Campus-wide radioactivewaste minimization plan that shall specify feasible programs to reducegeneration of low-level radioactive wastes and mixed wastes. To ensurethe plan shall be implemented, the Campus shall provide the resourcesrequired by the plan.

Several actions described in these mitigation measures have been or are being implemented. Forexample, a waste minimization coordinator has been hired and certain elements of the waste minimizationplan have been implemented. Radiation safety classes continue to be conducted by EH&S. The Campushas had a surcharge program in place for several years whereby the cost of disposal for radioactivematerials is paid up front (in advance) at the time of purchase. Because the cost of disposal has risendrastically, the surcharge has also drastically increased, the use of radioactive materials has decreased, andthe volume of radioactive wastes generated has decreased. The ease of detection and consequences ofillegal disposal also have resulted in less radioactive waste released to the wastewater system.


Because this issue was already addressed in the 1994 LRDP EIR and is being implementedaccording to Campus policy, and the data indicate that low-level radioactive liquid wastes are well belowapplicable limits in both WWTP effluent and the South Fork of Putah Creek, this impact is considered lessthan significant.

Mitigation Measure



4.3-4 Upset or failure of the proposed WWTP filtration and/or disinfection systems could resultin the discharge of biohazardous materials in WWTP effluent in concentrations that couldcause illness in individuals ingesting water from the South Fork of Putah Creek. Thisimpact is considered less than significant.

This impact could potentially occur because of human contact with biohazardous materials in theSouth Fork of Putah Creek in the highly unlikely event of a discharge of effluent exceeding NPDES permitrequirements. This would be considered a highly unlikely event because the WWTP would be designedto at least Class II reliability standards; the NPDES requirements would govern the discharge of WWTPeffluent; and the overall plant is being designed to produce an effluent equivalent in quality to Title 22disinfected tertiary recycled water (see page 4.3-9), which is suitable for unrestricted reuse and isconsidered safe for full body contact recreation (e.g., swimming).

The following is a qualitative evaluation of the potential for human exposure to infectious agents bydischarge of treated effluent to Putah Creek that is based on four factors:

n the exposed population;n microbial characteristics, including viability and virulence;n the environmental setting, including exposure medium, fate, and transport; andn regulatory requirements and treatment processes.

A comparison of the MID with the preliminary estimates of exposure doses for a single eventindicates that the concentration of all infectious agents in WWTP effluent, with one exception, would bebelow the MID (Tables 4.3-4 and 4.3-5). The exception would be for Giardia, assuming worst-caseremoval conditions at the WWTP that theoretically could occur following a plant upset or failure of thefiltration and/or disinfection systems. Under such conditions, effluent Giardia concentrations could exceedthe MID (Olivieri pers. comm.). The proposed WWTP would be designed to produce an effluentequivalent in quality to Title 22 disinfected tertiary recycled water, and the treatment train of secondarytreatment, filtration, and final effluent disinfection to a 7-day median of 2.2 MPN/100 ml would producean effluent deemed acceptable by DHS for a recreational impoundment and full body contact recreation.


As an additional precaution, in the unlikely event that the WWTP effluent would exceed coliform limits asa result of upset or failure, the Campus would be required by the RWQCB to post signs along the creeknotifying the public not to go in the water.


Table 4.3-5. Expected Estimated Concentrationand Removal of Pathogens in Treated Wastewater

Enteric Viruses(pfu/L)

Salmonella spp.(organisms/L)

Cryptosporidiumspp. (oocysts/L)

Giardia spp.(cysts/L)

Concentration inuntreatedwastewater

1,000 8,000 103-104 102-105

Removal duringtertiary treatment:

% removal 99.98-99.999999 99.99-99.999999 98.5-99.9999 98.5-99.9999

Concentrationremaining

0.2-0.00001 0.8-0.00008 low: 1.5-150high: 0.0001-0.01

low: 1.5-1500high: 0.0001-0.01

Notes: Low assumes worst-case removal.High assumes best-case removal.pfu = particle forming units.L = liter.

Sources: Feachem et al. 1983, Rowe and Abdel-Magid 1995, Yates n.d., Bitton 1994.


While the treated WWTP effluent would be safe for public contact, the ambient creek water (andrunoff into it) may not be because of background Giardia and/or Cryptosporidium levels from wild anddomestic animals in the adjacent watershed. It is highly likely that Giardia and Cryptosporidium spp. arepresent at high background levels in the South Fork of Putah Creek during winter rainfall runoff conditions. There also could be background levels of pathogens such as Giardia in the creekbed that could furtherincrease summer levels. Investigations conducted by Rose et al. (1991) indicate that levels ofCryptosporidium could average 430 oocysts/L and levels of Giardia 30 cysts/L in surface waters, valuesthat are well above (approximately an order of magnitude above) those that could be expected underworst-case conditions from the WWTP discharge.

For the present analysis of the potential risk associated with exposure to HIV, the CaliforniaRegional Primate Research Center Expansion EIR (University of California, Davis 1993a) and the WestCampus Wastewater System Connection EIR (University of California, Davis 1993b) were reviewed. In addition, a literature review was conducted on this subject by Dr. Richard E. Danielson, University ofCalifornia, Berkeley, and Dr. Adam Olivieri of EOA, Inc., who are considered technical experts on thisissue, to determine whether there were new findings that would substantially alter the conclusions reachedin these two prior documents.

Substantial background information and data were presented in Chapter 3.1 and Appendices Cand D of the California Regional Primate Research Center Expansion EIR (University of California,Davis 1993a) and in Chapter 3.7 and Appendices E and F of the West Campus Wastewater SystemConnection EIR (University of California, Davis 1993b) regarding the risk of exposure to HIV, SIV, andother similar viruses in untreated or treated wastewater. Copies of these reports are available for reviewduring normal office hours at the UC Davis Planning and Budget Office and are hereby incorporated byreference. Both EIRs concluded that the risk for HIV and SIV transmission from wastewater to workers,the local community, or local wildlife is virtually nonexistent. This conclusion was based on the existingprotocols being used by the Campus and other epidemiological factors, which both greatly reduce thepossibility of this occurrence. Protection from biohazardous materials is provided to Campus employeesand the community by a variety of engineering, administrative, and personal protective equipment controls. Each type of control is aimed at minimizing a potential route of entry by the agent to the worker. Exposureto biohazardous agents can occur through (1) inhalation, (2) ingestion, (3) absorption through skin ormucous membranes, and (4) penetration through broken skin. To minimize workers’ exposure to hazards,the Campus has established a Biosafety Program. In accordance with applicable UC Davis policy,protective measures are used and protective clothing is worn when working with biohazardous material toprevent exposure by skin contact. The potential for ingestion of hazardous biological agents would beminimized by following the UC Davis policy banning eating in laboratories using biohazardous materials, andrequiring proper washing.

Specific controls to reduce the potential for release of biohazardous materials to the sewer havealso been implemented. Animal cages are hosed daily with a disinfectant solution in accordance withNational Institutes of Health guidelines. Indoor animal cages are sanitized every two weeks at CRPRC’scage washing facility. In the process, cages are washed down with chemical disinfectant with 5 minutecontact time/rinse, or steam cleaned with a steam gun or put through a cage washer at an elevated (180°)


temperature for a given duration. Animal care wastes include animal excreta, bedding and uneaten food,cage washing solutions, animal carcasses and tissues, worker’s disposable protective clothing, sharp objects(including needles, scalpels, broken glass, etc.) in a disposable container, infectious waste and non-infectious waste. Sewage waste consists of urine, feces, and occasional menstrual blood in disinfectantsolution. The presence or lack of virus and/or bacteria in this effluent is based on the organism’ssurvivability through cage washing with disinfectant. The California Regional Primate Research CenterExpansion EIR (University of California, Davis 1993a) and the West Campus Wastewater SystemConnection EIR (University of California, Davis 1993b) also showed that the types of disinfectants usedare relatively effective in killing HIV in a short contact time.

Epidemiological factors include the survivability times of HIV outside the body, the receptivenessof animals to the virus, and the difficulty of transmission of the virus between humans. The two EIRsreferenced above (University of California, Davis 1993a and 1993b) stated that of viruses that may survivethe disinfectant process, HIV was found to be less able to survive in sewage than poliovirus, an intestinalvirus used as an indicator of the efficiency of treatment processes.

The University of California, Davis Campus Wastewater Treatment Plant Concept Report(Nolte and Associates 1995) indicates that the proposed WWTP would provide advanced secondarytreatment capable of meeting a 7-day median total coliform effluent discharge limit of < 2.2 MPN/100 mland a daily maximum limit of 23 MPN/100 ml. The anticipated WWTP effluent limits for disinfection wouldapply prior to discharge. A comparison of the proposed WWTP processes with current treatment andexposure requirements of Title 22 reclamation regulations for total coliform and turbidity was used toqualitatively assess the proposed WWTP discharge. Based on this review, the proposed WWTP filtrationand UV disinfection processes should provide a level of treatment equivalent to the DHS requirements fortertiary recycled water (see page 4.3-9). Water reclamation regulations contain specific plant reliabilityrequirements that must be met in addition to proper treatment processes being provided, such as continuouson-line turbidity meters, alarms, and backup equipment. Turbidity values of WWTP effluent prior to finaldisinfection would be expected to average less than 2 NTU but may exceed this value for short periodsduring extremely high flows and, even then, only during routine filter maintenance.

The pathogen removal rates and expected effluent concentrations following advancedsecondary/tertiary wastewater treatment are summarized in Table 4.3-5. Advanced secondary treatmentincludes chemical coagulation, flocculation using alum and/or polymer, the addition of chlorine for biomasscontrol, direct filtration with a pulsed bed rapid sand filter, and disinfection by UV light. The proposedWWTP treatment processes would provide removal rates that are similar to those used to develop theestimates contained in Table 4.3-5 (Olivieri pers. comm.).

The above analysis is summarized as follows:

n The proposed WWTP treatment processes would have proven ability and reliability to meetthe regulatory limits.


n Except for the rare occasions described above, the proposed WWTP discharge would bedesigned to produce an effluent equivalent in quality to Title 22 disinfected tertiary recycledwater, which is suitable for unrestricted use, including full body contact recreation. Tertiarydisinfected recycled water is deemed acceptable by DHS as protective of human health andas providing a level of acceptable risk for infectious agents.

n During a WWTP upset or failure of the filtration and/or disinfection systems, effluentconcentrations of Giardia could exceed the MID.

n The background Giardia levels in the South Fork of Putah Creek from domestic and wildanimals in the adjacent watershed are likely to be much higher than those in the proposedWWTP discharge.

Therefore, because of the factors summarized above, this impact is considered less than significant.

Mitigation Measure



Hazardous Waste

4.3-5 The proposed WWTP, in conjunction with 1994 LRDP development accommodated by theproposed project, would result in construction activities that could expose Campusoccupants and construction workers to contaminated soil or groundwater. This impact isconsidered potentially significant.

The 1994 LRDP EIR identified several locations on campus that are known or suspected to havebeen affected by chemical releases, pesticide use, or fuel spills or one type or another. There are alsoseveral contaminated structures. Other, undocumented areas of contamination are likely to be present oncampus. During development as allowed under the 1994 LRDP, contaminated soil or groundwater couldbe encountered. The following mitigation measures were identified to reduce this impact to a less-than-significant level.

4.6-16(a) During the site selection process for each site to be developed underthe 1994 LRDP, the Campus shall determine the need to have the site andadjacent areas investigated for the presence of hazardous materials orwastes by completing a “due diligence checklist”.


4.6-16(b) In the event that site inspections find evidence of chemical orradioactive contamination, waste discharges, underground storage tanks,abandoned drums, or other environmental impairment at locations to bedeveloped or in the project area, the Campus shall prepare a siteremediation plan that shall (1) specify measures to be taken to protectworkers and the public from exposure to potential site hazards and (2)certify that the proposed remediation measures would clean up thecontaminants, dispose of the wastes, and protect public health inaccordance with federal, state, and local requirements. Commencementof work in the areas of potential hazard shall not proceed until the siteremediation plan has been completed. Depending on the nature of anycontamination, appropriate agencies shall be notified (e.g., theCVRWQCB for groundwater contamination and the DTSC for soilcontamination [or the appropriate County Environmental HealthDepartment]). Provisions of the site remediation plan would be adoptedby the Campus as part of future projects.


Mitigation Measure


4.3-6 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, would result in the development of potentially contaminated sitesthroughout the region, possibly resulting in cumulative health and safety threats to siteworkers and the public. This impact is considered significant and unavoidable.

The 1994 LRDP EIR discussed the possibility that development in the Davis area close to theCampus could occur on contaminated sites. The potential exists for release of airborne chemicalcompounds during development and/or remediation of contaminated sites, from both Campus and off-Campus sites. In addition, cumulative impacts on groundwater could result from development and/orremediation work done on the Campus and in the adjacent community, increasing the likelihood of exposureof site workers and the public to such contamination. For these reasons, the cumulative effect of on-Campus and off-Campus development and/or remediation of contaminated sites is considered significant. The following mitigation measures were identified to reduce the magnitude of the impact; however, becausethe Campus cannot guarantee that other, surrounding jurisdictions (i.e., City of Davis, Yolo County andSolano County) would enforce and monitor similar mitigation measures geared to reduce risks associatedwith development of contaminated sites, this impact remains significant and unavoidable.

4.6-17 Implement Mitigation Measures 4.6-16(a) through (c).


Mitigation Measure


4.3-7 The proposed WWTP, in conjunction with 1994 LRDP development accommodated by theproposed project, could result in the exposure of Campus occupants and constructionworkers to contaminated building materials. This impact is considered potentiallysignificant.

The 1994 LRDP identified a number of buildings on Campus as known or suspected as containinghazardous materials such as asbestos, PCBs, mercury, radioactive contamination, and old researchlaboratory chemicals. These materials could cause adverse health impacts if human exposure is permittedduring demolition and renovation. The proposed WWTP project includes demolition of the existingWWTP. The following mitigation measures were identified to reduce this impact to a less-than-significantlevel.

4.6-18(a) During the site selection process for each site to be developed underthe 1994 LRDP, the Campus shall determine the need to have existingbuildings on each site investigated for the presence of hazardousmaterials or wastes by completing a “due diligence checklist”.

If further investigation is warranted, the investigation shall be carriedout by a Registered Environmental Assessor (i.e., a professional en-vironmental scientist or engineer registered in California) or aregistered engineer. The investigations shall be environmental audits,which shall include, at a minimum, site inspections for hazardousmaterials, examination of historic records for evidence of hazardousmaterials, examination of historic records for evidence of hazardousmaterials use, interviews with Campus personnel, and review ofCampus records for evidence of contamination.

For each site audit, the qualified person shall prepare a reportdetailing the results of the inspection and submit it to appropriateCampus offices. The report preparer shall either certify that the siteis free of hazards, recommend further investigations, or recommendpreparing a site mitigation plan. After reviewing and accepting thereport, reviewing offices shall submit it to the Planning and BudgetOffice (the office responsible for site selection and environmentalreview on Campus) with their recommendations. The Campus shallensure that inspection reports are completed prior to excavation orconstruction at the development site.


4.6-18(b) In the event that site inspections find evidence of chemical orradioactive contamination in buildings at sites to be developed, theCampus shall prepare a site remediation plan that shall (1) specifymeasures to be taken to protect workers and the public from exposure topotential site hazards and (2) certify that the proposed remediationmeasures would clean up the contaminants, dispose of the wastes, andprotect public health in accordance with federal, state, and localrequirements. Commencement of work in the areas of potential hazardshall not proceed until the site remediation plan has been completed. Depending on the nature of any contamination, appropriategovernmental agencies shall be notified. Provisions of the siteremediation plan would be adopted by the Campus as part of futureprojects.


Mitigation Measure


4.3-8 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, would result in the demolition or renovation of buildings that couldpose cumulative health and safety threats to site workers and the public. This impact isconsidered less than significant.

Demolition or renovation of contaminated off-Campus buildings is likely to occur in connection withdevelopment in the Davis area. The regulation of materials that have the potential for being airborne (e.g.,friable asbestos) is extremely stringent. Campus demolition and renovation would have a less-than-significant impact following mitigation related to site investigation and development of site remediation plansand site health and safety plans. Although there could be some small residual impact following mitigation,such an impact would only affect those persons on the demolition or renovation site. For this reason, thisimpact would not in all likelihood accumulate with any off-Campus demolition or renovation effects, andis therefore deemed less than significant. No mitigation was required in the 1994 LRDP EIR.

Mitigation Measure



Chapter 4.4 Biological Resources

INTRODUCTION

Information on biological resources is based on field surveys of the project site, a review of the1994 LRDP EIR, a review of the California Department of Fish and Game’s (DFG’s) Natural DiversityData Base (NDDB) (1995), a review of the California Native Plant Society’s (CNPS’s) Inventory of Rareand Endangered Vascular Plants of California (Skinner and Pavlik 1994), a review of pertinentliterature, and contact with knowledgeable individuals.

A botanist and wildlife biologist conducted a site assessment for significant natural habitats andhabitat for special-status species on December 1, 1995. Surveys for special-status plants were alsoconducted on April 24, 1996. Additional wildlife surveys were conducted on January 7, June 28, July 7,August 10, and September 4, 1996. The biologists walked transects over the entire project site, focusingon areas with high-quality biological resources or areas at the existing WWTP with potential for special-status species. An abandoned water tank at the existing WWTP was surveyed for bats.


The study area is located in the Californian Floristic Province (Hickman 1993) in the southernSacramento Valley. Vegetation at the proposed WWTP site is agricultural land primarily used for pasture. The utility and pipeline corridors are a mosaic of ruderal/annual grassland, cropland, and urban ornamentallandscaping. A thin band of riparian vegetation is present along Putah Creek.

Habitat Types

The habitat types in the project area can be described as agricultural lands (consisting of croplandand pasture), ruderal/annual grassland, valley-foothill riparian woodland, riverine (the open water habitatof the South Fork of Putah Creek), and urban ornamental habitat as defined by the Wildlife HabitatRelationship (WHR) system. The WHR defines habitats based on the composition and structure of the


dominant vegetation of any given area and provides generalized information pertaining to wildlife value anduse of these habitat types. The following is a description of the habitat types that could be affected by theproposed project. Figure 4.4-1 illustrates the location and extent of these habitat types; Appendix H,“Biological Resources”, includes a listing of species that could occur in the project area and identifies thosespecies observed during field surveys.

Agricultural Lands

Agricultural lands include cropland/pasture habitat composed of an annual herbaceous plant speciescover type and orchard/vineyard habitat composed of a perennial woody plant species cover type. Noorchard/vineyard habitat would be affected by the project; therefore, the following discussion relates onlyto cropland.

Cropland is used for cultivation of agricultural commodity crops or for agricultural research andeducation. Pasture is land planted in perennial forage grasses and legumes and is actively grazed. Pastureis often irrigated in dry months to provide a continuous green feed for livestock.

Vegetation. Pasture at the proposed WWTP site is planted with typical turf-forming, non-nativegrasses and legumes such as tall fescue, dallis grass, and clover. Cropland to the east of the project sitewas being planted in row crops at the time of the surveys.

Wildlife. The pasture provides food and minimal cover for wildlife. The grazed fields provideforaging habitat for many wildlife species and also limit use of the fields by other wildlife species. Raptors(e.g., red-tailed hawks, Swainson’s hawks, northern harriers, white-tailed kites, and great-horned owls)forage in the croplands and pastures. Western meadowlarks, American pipits, mourning doves, andEuropean starlings were observed foraging in the pastures.

Ruderal/Annual Grassland

Ruderal/annual grassland exists in the project area wherever past land disturbances have resultedin the removal of natural vegetation, allowing a site to become colonized with aggressive weedy grasslandspecies. Examples of ruderal/annual grassland can be found along roadsides, inside the levee banks alongthe South Fork of Putah Creek, around the sludge drying ponds, and along the edges of agricultural fields.

Vegetation. Ruderal/annual grassland is dominated by a mixture of non-native annual grasses andannual and perennial herbs. Typical grass species found in this habitat type include hare barley, ripgut grass,soft chess, and Johnson grass. Typical herbs in ruderal/annual grassland include alkali mallow, jimson-weed, dove weed, and yellow star-thistle.

Wildlife. Ruderal and annual grassland habitats found along the levee banks and upland floodplainof the South Fork of Putah Creek provide food, cover, and movement corridors for small- to medium-sized


mammals, resident and migratory songbirds, reptiles, and amphibians. Small- to medium-sized mammalsthat have been observed in the ruderal/annual grassland habitats in the project area include coyotes,California jackrabbits, striped skunks, California voles, California ground squirrels, Audubon’s cottontails,Botta’s pocket gophers, gray foxes, and red foxes.

Many birds, amphibians, and reptiles also use the ruderal/grassland habitats in the project area,including ring-necked pheasants, California quail, lesser and American goldfinches, house finches, Americancrows, savannah sparrows, yellow-billed magpies, western meadowlarks, western toads, Pacific treefrog,southern alligator lizards, common kingsnakes, gopher snakes, and western fence lizards.

Valley-Foothill Riparian Woodland

Valley and foothill riparian woodland in the project area is represented by intact woodlandformations along the South Fork of Putah Creek.

Vegetation. The valley and foothill riparian woodland in the project area consists of valley oaks,Fremont’s cottonwoods, black willows, red willows, arroyo willows, Oregon ash, and California box elder. Characteristic shrubs include yellow willow, sandbar or narrow-leaved willow, and blue elderberry. Valleyand foothill riparian habitat along the South Fork of Putah Creek in the vicinity of the existing outfall consistspredominantly of shrubby willow species. The riparian habitat in this area is subjected to frequentdisturbance by scouring flood flows and human intrusion and lacks the overstory vegetation of more matureriparian systems.

Wildlife. The riparian habitat along the South Fork of Putah Creek supports moderate-qualityhabitat for wildlife. The riparian habitat along the South Fork of Putah Creek is the highest quality wildlifehabitat in the project area, providing food; water; migration and dispersal corridors; and escape, breeding,and thermal cover for many wildlife species.

Riverine and Open Water Pond

Riverine habitat consists of the open water areas of the South Fork of Putah Creek and ArboretumWaterway. The riparian habitat associated with the riverine habitat is the terrestrial component of thisinterdependent system (University of California, Davis 1994).

Vegetation. No emergent vegetation was observed in the riverine or open water habitats.

Wildlife. The riverine habitat in the South Fork of Putah Creek provides high-quality habitat foraquatic and semi-aquatic wildlife. Beavers are common along the South Fork of Putah Creek. Beaverdams provide backwater habitat for many species, including valley garter snakes, western terrestrial gartersnakes, pond turtles, Pacific tree frogs, western toads, great blue herons, great egrets, green herons, and


black-crowned night-herons. Waterfowl also forage or roost along the South Fork of Putah Creek; theseinclude mallards, wood ducks, and green-winged teal.

Urban Landscaping

Urban ornamental habitat is the landscaped areas (consisting of trees, shrubs, and lawn) in thevicinity of the existing WWTP and at the proposed WWTP site.

Vegetation. Vegetation in this habitat type is predominantly non-native trees and shrubs plantedfor their aesthetic appeal and ease of maintenance. The only noteworthy vegetation in this habitat type isa stand of coast redwood trees that border La Rue Road along the north edge of the existing WWTP. Thisstand, consisting of several trees, is of medium age and good health and provides a visual screen for theexisting WWTP.

Wildlife . The ornamental vegetation has low wildlife value. Many birds have adapted to the urbanenvironment, including Nuttall’s woodpeckers, scrub jays, American robins, yellow-rumped warblers,northern mockingbirds, and yellow-billed magpies. No bats were observed in an abandoned water tankat the existing WWTP.

Fish Resources

South Fork of Putah Creek

Putah Creek is one of the largest streams draining the eastern Coast Range within the SacramentoRiver drainage. The flow in the South Fork of Putah Creek at the Campus is primarily regulated by releasesof water from the Solano Diversion Dam. In the area of the creek that could potentially be affected by theproposed project, the South Fork of Putah Creek is a warmwater, intermittent stream. In some dry years,potentially affected sections of the stream exist only as scattered pools. In drier years, the pools that doremain in the vicinity of the Campus are solely fed by discharges from the Campus. The existing permitteddischarges from Campus facilities that create pools include the Putah Creek Aquaculture Facility and theAquatic Center (two aquaculture research facilities), the Aquatic Weed Control Laboratory, the ArboretumWaterway, and the existing WWTP. Discharges from the WWTP represent the largest discharge to thecreek and provide a fairly consistent water source year round.

Effects of dry-year conditions on fish resources were especially evident in 1989, 1990, and 1991,when most of the creek below Stevenson Bridge dried up, and thousands of fish, crayfish, and clams werekilled. The only fish that survived were those that retreated to the remnant pools in the creek, includingthose pools that were artificially maintained by discharges from the Campus.


The fish fauna present in the South Fork of Putah Creek is a mix of native and introduced species. Table H-3 in Appendix H lists fish collected on the stretch of the creek on the Campus between 1980 and1995. Historically, the fish fauna in the lower reaches of Putah Creek responded to changes in flow, watertemperature, vegetation, and competition with introduced species. The reaches of Putah Creek occupiedby various fish species now vary as a result of the water release rates from the Solano Diversion Dam andpool-forming discharges from the Campus.

The section of the South Fork of Putah Creek that passes through the Campus is dominated by fishspecies that are adapted to warmwater and ponded conditions, such as largemouth bass, green sunfish,Sacramento blackfish, hitch, carp, black bullhead, white crappie, and catfish. Occasionally, during wetyears, anadromous fish have migrated upstream through reaches of the creek on the Campus. No state-listed or federally listed threatened or endangered fish species or sensitive species are known to be presentin the South Fork of Putah Creek near the Campus (Moyle pers. comm.).

Special-Status Species

Special-status species are plants and animals that are legally protected under state and federalEndangered Species Acts (ESAs) or other regulations, and species that are considered sufficiently rare bythe scientific community to qualify for such listing. Special-status plants are species in the followingcategories:

n plants listed or proposed for listing as threatened or endangered under the federal ESA (50Code of Federal Regulations [CFR] 17.12 [listed plants] and various notices in the FederalRegister (FR) [proposed species]);

n plants that are candidates for possible future listing as threatened or endangered under thefederal ESA (61 FR 40, February 28, 1996);

n plants listed or proposed for listing by the State of California as threatened or endangeredunder the California ESA (14 California Code of Regulations [CCR] 670.5);

n plants listed under the California Native Plant Protection Act (Cal. Fish and Game Code,Section 1900 et seq.);

n plants that meet the definitions of rare or endangered under CEQA (CEQA Guidelines, Section15380);

n plants considered by CNPS to be “rare, threatened, or endangered in California” (Lists 1B and2 in Skinner and Pavlik 1994); and

n plants listed by CNPS as plants about which more information is needed to determine theirstatus and plants of limited distribution (Lists 3 and 4 in Skinner and Pavlik 1994), which may


be included as special-status species on the basis of local significance or recent biologicalinformation.

Special-status animals are species in the following categories:

n animals listed or proposed for listing as threatened or endangered under the federal ESA (50CFR 17.11 [listed animals] and various notices in the FR [proposed species]);

n animals that are candidates for possible future listing as threatened or endangered under thefederal ESA (61 FR 40, February 28, 1964);

n species of concern to the U.S. Fish and Wildlife Service (USFWS) (Noda pers. comm.);

n migratory nongame birds of management concern to the USFWS;

n animals that meet the definitions of rare or endangered under CEQA (CEQA Guidelines,Section 15380);

n animals listed or proposed for listing by the State of California as threatened or endangeredunder the California ESA (14 CCR 670.5);

n animal species of special concern to DFG (Remsen 1978 [birds] and Williams 1986[mammals]); and

n animals fully protected in California (Cal. Fish and Game Code, Section 3511 [birds], 4700[mammals], and 5050 [reptiles and amphibians]).

Plants

A list of special-status plant species that are known or suspected to occur in the general vicinity ofthe project area was compiled based on information in DFG’s NDDB (1995) and the CNPS Inventoryof Rare and Endangered Vascular Plants of California (Skinner and Pavlik 1994). Although theNDDB (1995) did not contain any records of special-status plant species at the project site or in theimmediate vicinity, 12 species have moderate to low potential to occur there (Table 4.4-1).

Many of the special-status plant species with potential to occur in the project area inhabit areas withalkaline soils either within alkaline grassland or alkaline flats. A review of the Soil Survey of Yolo County,California (U.S. Soil Conservation Service 1972) did not reveal the presence of any alkaline affected soilin the immediate vicinity of the project area. The lack of alkaline soil map units in the project area does notpreclude the presence of small unmapped inclusions of alkaline soils; however, if alkaline inclusions do existin the project area, they have been so significantly disturbed that the likelihood that they support special-status plant species is extremely low.


Three special-status plant species have moderate potential to occur in the project area: Sanford’ssagittaria, rose mallow, and northern California black walnut. Sanford’s sagittaria and rose mallow arefound in marshes or swamps. Marginal habitat for these two species can be found along the South Forkof Putah Creek. Northern California black walnut has been extirpated from much of its original range. Historically, the species occurred in Yolo County; however, now the only remaining natural stands occurin Napa and Contra Costa counties (Skinner and Pavlik 1994, Natural Diversity Data Base 1995). Northern California black walnut has been widely used throughout California as rootstock for Englishwalnut, a common commodity species. English walnut and northern California black walnut also hybridizefreely. Specimens of northern California black walnut reported to occur on campus in the 1994 LRDP EIRprobably represent naturalized rootstock or English walnut hybrids and are not naturally occurringspecimens.

Surveys for special-status plant species were conducted on April 24, 1996. No special-statusplant species were found during the surveys. Past land disturbance and modification has resulted in theremoval of nearly all naturally occurring vegetation. Plant species encountered during these surveys aretypical of disturbed agricultural settings in the Central Valley. The lack of wetland or alkaline habitats andpast disturbance at the project site precludes the possibility that rose mallow, Sanford’s sagittaria,brittlescale, heartscale, San Joaquin spearscale, palmate-bracted bird’s-beak, or Heckard’s pepper grassoccupy the site; therefore, no late season surveys are warranted.

Wildlife

Thirty-three special-status wildlife species have the potential to occur in the vicinity of the projectarea (Table 4.4-2). The following 10 special-status species are known to occur in the affected area, orsuitable habitat is present for the species: Swainson’s hawk, burrowing owl, loggerhead shrike,northwestern pond turtle, garter snake, valley elderberry longhorn beetle (VELB), delta June beetle,Sacramento Valley tiger beetle, Sacramento anthicid beetle, and Antioch multilid wasp. These species areaddressed in the impact analysis section of this chapter.

There is no suitable breeding habitat in the affected area for the ringtail, white-faced ibis, northernharrier, western yellow-billed cuckoo, bank swallow, or California red-legged frog.

The following species are visitors that do not breed in the project area: osprey, bald eagle, sharp-shinned hawk, Cooper’s hawk, ferruginous hawk, golden eagle, American peregrine falcon, prairie falcon,greater sandhill crane, long-billed curlew, short-eared owl, willow flycatcher, California yellow warbler,yellow-breasted chat, and tricolored blackbird. The white-tailed kite nests along the South Fork of PutahCreek; one fledgling kite was observed about 2,200 feet east of Old Davis Road during the 1996 fieldsurveys (Figure 4.4-1).

Swainson’s Hawk . The Swainson’s hawk is listed as a threatened species under the CaliforniaESA. Historically, it nested throughout lowland California; however, the current Swainson’s hawk nesting


distribution is limited to extreme northeastern California, the Central Valley, and a few isolated locations inthe Owens Valley (California Department of Fish and Game 1994). The Swainson’s hawk inhabitsCalifornia only during the breeding season (March through September) and winters in South America.

Historically, as many as 17,000 Swainson’s hawk pairs may have nested in California (CaliforniaDepartment of Fish and Game 1994). Currently, an estimated 550 Swainson’s hawk pairs nest in the state(California Department of Fish and Game 1994). The Central Valley supports an estimated 440 of theremaining nesting pairs.

Table 4.4-1. Special-Status Plant Species with the Potential to Occur in the UCD Proposed WWTP Project AreaPage 1 of 2

Legal Status*Scientific NameCommon Name Federal State CNPS California Distribution Habitats Blooms

Potential to Occurin the Project Area

Astragalus tener var. ferrisiae“Ferris's milk-vetch”

-- -- 1B Butte, Colusa (extirpated), Solano (extirpated),Sutter (extirpated), Yolo (extirpated)

Meadows (vernally mesic),valley and foothill grassland(subalkaline flats)

April-May Low; habitat heavilydisturbed or absent

Astragalus tener var. tener“Alkali milk-vetch”

-- -- 1B Alameda (extirpated), Contra Costa (extirpated),Merced, Monterey (extirpated), Napa, San Benito(extirpated), Santa Clara (extirpated), SanFrancisco (extirpated), San Joaquin (extirpated),Solano, Sonoma (extirpated), Stanislaus(extirpated), Yolo

Playas, valley and foothillgrassland (adobe clay), vernalpools (alkaline)

March-June Low; habitat heavilydisturbed or absent

Atriplex cordulata“Heartscale”

-- -- 1B Alameda, Butte, Contra Costa, Fresno, Glenn,King, Kern, Madera, Merced, San Joaquin(extirpated), Solano, Stanislaus (extirpated),Tulare

Chenopod scrub, valley andfoothill grassland (sandy) /saline or alkaline

May-October Very low; habitatabsent

Atriplex depressa“Brittlescale”

-- -- 1B Alameda, Butte, Contra Costa, Colusa, Fresno,Glenn, Kern, Madera, Merced, Solano, Stanislaus(extirpated), Tulare, Yolo

Chenopod scrub, playas, valleyand foothill grassland /alkaline, clay

May-October Very low; habitatabsent

Atriplex joaquiniana“San Joaquin spearscale”

-- -- 1B Alameda, Contra Costa, Colusa, Glenn, Merced,Napa, Sacramento, San Benito, Santa Clara(extirpated), San Joaquin (extirpated), Solano,Tulare (extirpated), Yolo

Chenopod scrub, Meadows,valley and foothill grassland /alkaline

April-September Low; habitat heavilydisturbed or absent

Cordylanthus palmatus“Palmate-bracted bird’s-beak”

FE CE 1B Alameda, Colusa, Fresno, Madera, San Joaquin(extirpated), Yolo

Chenopod scrub, valley andfoothill grassland (alkaline)

May-October Low; habitat heavilydisturbed or absent

Fritillaria liliacea“Fragrant fritillary”

-- -- 1B Alameda, Contra Costa, Monterey, Marin, SanBenito, Santa Clara, San Francisco, San Mateo,Solano, Sonoma

Coastal prairie, coastal scrub,valley and foothill grassland /often serpentinite

February-April Low; habitat heavilydisturbed or absent

Fritillaria pluriflora“Adobe-lily”

-- -- 1B Butte, Colusa, Glenn, Lake, Napa, Plumas,Solano, Tehama, Yolo

Chaparral, cismontanewoodland, valley and foothillgrassland / often adobe

February-April Low; habitat heavilydisturbed or absent

Hibiscus lasiocarpus“Rose-mallow”

-- -- 2 Butte, Contra Costa, Colusa, Glenn, Sacramento,San Joaquin, Solano, Sutter, Yolo, widespreadoutside California

Marshes and swamps(freshwater)

August-September Moderate, suitablehabitat along PutahCreek

Juglans californica var. hindsii -- -- 1B Contra Costa, Napa, Sacramento [extirpated), Riparian forest, riparian April-May Introduced specimens

Table 4.4-1. Special-Status Plant Species with the Potential to Occur in the UCD Proposed WWTP Project AreaPage 1 of 2

Legal Status*Scientific NameCommon Name Federal State CNPS California Distribution Habitats Blooms

Potential to Occurin the Project Area

“Northern California black walnut” Solano [extirpated), Yolo [extirpated) woodland occur along PutahCreek

Lepidium latipes var. heckardii“Heckard's pepper-grass”

-- -- 1B Yolo Valley and foothill grassland(alkaline flats)

April-May Low; habitat heavilydisturbed or absent

Sagittaria sanfordii“Sanford's arrowhead”

-- -- 1B Butte, Del Norte, Fresno, Kern, Merced, Marin,Orange [extirpated], Sacramento, Shasta, SanJoaquin, Tehama, Ventura [extirpated]

Marshes and swamps (assortedshallow fresh water)

May-August Moderate; suitablehabitat along PutahCreek

_______________

* Status explanations:

Federal

-- = no listing status.FE = listed as endangered under the federal Endangered Species Act.

State

-- = no listing status.CE = listed as endangered under the California Endangered Species Act.

California Native Plant Society

1B = List 1B species: rare, threatened, or endangered in California and elsewhere.2 = List 2 species: rare, threatened, or endangered in California but more common elsewhere.

Sources: Skinner and Pavlik 1994; University of California, Davis 1994; Jones & Stokes Associates file information.

Table 4.4-2. Special-Status Wildlife Specieswith the Potential to Occur in the Vicinity

of the UC Davis Proposed WWTP Project AreaPage 1 of 7

Common NameScientific Name

Statusa

(Federal/State) California Distribution Habitats Reason for Decline or Concern Potential to Occurin the Project Area

Mammals

RingtailBasariscus astutas

--/FP Sierra Nevada and Coast Ranges and theCentral Valley; upper and middleportions of the Sacramento River,Feather River, and Bobelaine Sanctuary;potentially occurs in riparian woodlandsin Chico area

Riparian forests, chaparral, brushlands,oak woodlands, and rocky hillsides

Loss and fragmentation of lowlandriparian habitat

Low to none; no records; no suitablebreeding habitat

Birds

OspreyPandion haliaetus

--/SSC Nests along the north coast from MarinCounty to Del Norte County, eastthrough the Klamath and CascadeRanges, and the upper SacramentoValley; important inland breedingpopulations at Shasta Lake, Eagle Lake,and Lake Almanor, and small numberselsewhere south through the SierraNevada; winters along the coast fromSan Mateo to San Diego County

Nests in snags or cliffs or other high,protected sites near the ocean, largelakes, or rivers with abundant fishpopulations

Vulnerable to human disturbance at nestsites; pesticide contamination; breedingrange and populations increasing inmany areas

No nesting records; occasional visitoralong lower Putah Creek

White-tailed kite Elanus leucurus

--/FP Lowland areas west of Sierra Nevadafrom head of Sacramento Valley south,including coastal valleys and foothills towestern San Diego County at theMexico border

Low foothills or valley areas with valleyor live oaks, riparian areas, andmarshlands near open grasslands forforaging

Loss of grassland and wetland habitats toagriculture and urban development

Moderate; one fledgling was observedalong the South Fork of Putah Creek,about 2,200 feet east of Old Davis Road;suitable nesting habitat exists along theSouth Fork of Putah Creek

Bald eagleHaliaeetus leucocephalus

E/T Nests in Siskiyou, Modoc, Trinity,Shasta, Lassen, Plumas, Butte, Tehama,Lake, and Mendocino Counties and inthe Lake Tahoe Basin; reintroduced intocentral coast; winter range includes therest of California, except the southeasterndeserts, very high altitudes in theSierras, and east of the Sierra Nevadasouth of Mono County; range expanding

In western North America, nests androosts in coniferous forests within 1 mileof a lake, a reservoir, a river, or the ocean

Nest sites vulnerable to humandisturbance; pesticide contamination

No nesting records; occasional wintervisitor along the South Fork of PutahCreek

Northern harrierCircus cyaneus

--/SSC Throughout lowland California; has beenrecorded in fall at high elevations

Grasslands, meadows, marshes, andseasonal and agricultural wetlandsproviding tall cover

Loss of habitat to agricultural and urbandevelopment

Moderate; no nesting records; nosuitable nesting habitat; observedforaging in agricultural fields

Sharp-shinned hawkAccipiter striatus

--/SSC Permanent resident on the Sierra Nevada,Cascade, Klamath, and north CoastRanges at midelevations, as well asalong the coast in Marin, San Francisco,San Mateo, Santa Cruz, and MontereyCounties; winters over the rest of thestate except very high elevations

Dense-canopy ponderosa pine or mixed-conifer forest and riparian habitats

Human disturbance at nest sites;pesticide contamination; timberharvesting near nesting sites

Does not nest in Yolo County;occasional winter visitor




Statusa


Cooper's hawkAccipiter cooperi

--/SSC Throughout California except highaltitudes in the Sierra Nevada; winters inthe Central Valley, southeastern desertregions, and plains east of the CascadeRange; permanent residents occupy therest of the state

Nests primarily in riparian forestsdominated by deciduous species; alsonests in densely canopied forests fromdigger pine-oak woodland up toponderosa pine; forages in openwoodlands

Human disturbance at nest sites; loss ofriparian habitats, especially in theCentral Valley; pesticide contamination

Does not nest in eastern Yolo County;regular winter visitor

Swainson's hawkButeo swainsoni

--/T Lower Sacramento and San JoaquinValleys, the Klamath Basin, and ButteValley; the state’s highest nestingdensities occur near Davis andWoodland, Yolo County

Nests in oaks or cottonwoods in or nearriparian habitats; forages in grasslands,irrigated pastures, and grain fields

Loss of riparian, agriculture, andgrassland habitats; vulnerable to humandisturbance at nest sites

More than 30 recorded nest sites on andwithin ½ mile of Campus; nests in theArboretum, along Old Davis Road, andalong the North and South Forks ofPutah Creek

Ferruginous hawkButeo regalis

SC,MNBMC/SSC

Does not nest in California; wintervisitor along the coast from SonomaCounty to San Diego County, eastwardto the Sierra Nevada foothills and south-eastern deserts, the Inyo-WhiteMountains, the plains east of theCascade Range, and Siskiyou County

Open terrain in plains and foothillswhere ground squirrels and other prey areavailable

Conversion of grasslands for agricultureand urban development

Occasional winter visitor in agriculturalfields

Golden eagleAquila chrysaetos

--/SSC, FP Foothills and mountains throughoutCalifornia; uncommon nonbreedingvisitor to lowlands such as the CentralValley

Cliffs and escarpments or tall trees fornesting; annual grasslands, chaparral,and oak woodlands with plentifulmedium and large-sized mammals forprey

Habitat loss to urbanization; vulnerableto disturbance at nest sites

Does not nest in eastern Yolo County;occasional winter visitor

American peregrine falconFalco peregrinus anatum

E/E Permanent resident on the north andsouth Coast Ranges; may summer onthe Cascade and Klamath Ranges souththrough the Sierra Nevada to MaderaCounty; winters in the Central Valleysouth through the Transverse andPeninsular Ranges and the plains east ofthe Cascade Range

Nests and roosts on protected ledges ofhigh cliffs, usually adjacent to lakes,rivers, or marshes that support largepopulations of other bird species

Pesticide contamination; populationrecovering

Does not nest in Yolo County;occasional migrant or winter visitor

Prairie falconFalco mexicanus

--/SSC Found as permanent resident on thesouth Coast, Transverse, Peninsular, andnorthern Cascade Ranges; thesoutheastern deserts; Inyo-WhiteMountains; Modoc, Lassen, and PlumasCounties; and the foothills surroundingthe Central Valley; winters in theCentral Valley, along the coast fromSanta Barbara County to San DiegoCounty, and in Marin, Sonoma,Humboldt, Del Norte, and InyoCounties

Cliffs or escarpments for nesting;adjacent dry, open terrain or uplands,marshes, and seasonal marshes forforaging

Possible pesticide contamination;robbing of eyries by falconers and illegalshooting; human disturbance at nest site

Does not nest in eastern Yolo County;occasional visitor

Greater sandhill crane --/T Breeds on the plains east of the Cascade Summers in open terrain near shallow Loss of freshwater marsh nesting habitat; Low; rare visitor; no known foraging




Statusa


Grus canadensis tabida Range and south to Sierra County;winters in the Central Valley, southernImperial County, Lake Havasu NationalWildlife Refuge, and the Colorado RiverIndian Reserve

lakes or freshwater marshes; winters inplains and valleys near bodies of freshwater

disturbance by cattle during nesting;illegal hunting

areas

Long-billed curlewNumenius americanus

--/SSC Nests in northeastern California inModoc, Siskiyou, and Lassen Counties;winters along coast or in interior valleyswest of Sierra Nevada

Nests at high-elevation grasslandsadjacent to lakes or marshes in migrationand winter; frequents coastal beaches andmudflats or interior grasslands andagricultural fields

Loss of wetland and grassland habitats tourbanization and agriculture

Low; uncommon visitor in agriculturalfields; none observed during field survey

Western yellow-billed cuckooCoccyzus americanus occidentalis

MNBMC/E Nests along the upper Sacramento, lowerFeather, south fork of the Kern,Amargosa, Santa Ana, and ColoradoRivers

Wide, dense, riparian forests with a thickunderstory of willows for nesting; siteswith a dominant cottonwood overstoryare preferred for foraging; may avoidvalley oak riparian habitats where scrubjays are abundant

Loss of riparian habitat to agriculture andwater control development; possiblepesticide contamination

No potential for nesting; no recentrecords; no suitable nesting habitat inthe project area

Burrowing owlAthene cunicularia

SC,MNBMC/SSC

Lowlands throughout California,including the Central Valley,northeastern plateau, southeasterndeserts, and coastal areas; rare alongsouth coast

Rodent burrows in sparse grassland,desert, and agricultural habitats

Loss of habitat; human disturbance atnesting burrows

Observed nesting in the field north of theMedical Sciences complex in 1991; alsoobserved near the university airport in1994; observed nesting along thedrainage ditch along the east side of theUCD Raptor Center

Short-eared owlAsio flammeus

MNBMC/SSC Permanent resident along the coast fromDel Norte County to Monterey Countyalthough very rare in summer north ofSan Francisco Bay, in the Sierra Nevadanorth of Nevada County, in the plainseast of the Cascades, and in MonoCounty; small, isolated populations alsonest in the Central Valley; winters onthe coast from San Luis Obispo Countyto San Diego County, the Central Valleyfrom Tehama County to Kern County,the eastern Sierra Nevada from SierraCounty to Alpine County, the ChannelIslands, and Imperial County

Freshwater and saltwater marshes,lowland meadows, and irrigated alfalfafields; needs dense tules or tall grass fornesting and daytime roosts

Loss of wetland and grassland habitats toagriculture and urban development

Low to none; no nesting records; nosuitable nesting habitat exists in theproject area; none observed during fieldsurvey

Willow flycatcherEmpidonax traillii

SC/E Occurs in isolated areas in the mountainsof California

Riparian areas and large, wet meadowswith abundant willows for breeding;usually occurs in riparian habitats duringmigration

Loss of riparian breeding habitat; nestparasitism by brown-headed cowbirds

Low to none; no nesting records; nosuitable nesting habitat; occasionalmigrant

Bank swallowRiparia riparia

--/T The state’s largest remaining breedingpopulations are along the SacramentoRiver from Tehama County toSacramento County, and along the

Nests in bluffs or banks, usually adjacentto water, where the soil consists of sandor sandy loam to allow digging

Loss of natural earthen banks to bankprotection and flood control; erosioncontrol related to stream regulation bydams

No potential for nesting; no records; nosuitable nesting habitat; occasionalvisitor




Statusa


Feather and lower American Rivers, inthe Owens Valley; nesting areas alsoinclude the plains east of the CascadeRange south through Lassen County,northern Siskiyou County, and smallpopulations near the coast from SanFrancisco County to Monterey County

Loggerhead shrikeLanius ludovicianus

--/SSC Resident and winter visitor in lowlandsand foothills throughout California; rareon coastal slope north to MendocinoCounty, occurring only in winter

Prefers open habitats with scatteredshrubs, trees, posts, fences, utility lines,or other perches

Loss of habitat and pesticide use; stillwidespread

Observed on campus, but no nestingrecords were found; suitable nestinghabitat exists along the South Fork ofPutah Creek

California yellow warblerDendroica petechia brewsteri

--/SSC Nests over all of California except theCentral Valley, the Mojave Desertregion, and high altitudes in the SierraNevada; winters along the ColoradoRiver and in parts of Imperial andRiverside Counties; two smallpermanent populations in San Diego andSanta Barbara Counties

Nests in riparian areas dominated bywillows, cottonwoods, sycamores, oralders or in mature chaparral; may alsouse oaks, conifers, and urban areas nearstreamcourses

Loss of riparian breeding habitats; nestparasitism by brown-headed cowbirds

None for nesting; does not nest ineastern Yolo County; regular migrant

Yellow-breasted chatIcteria virens

--/SSC Uncommon migrant in California; nestsin a few locations with appropriatehabitat such as Sweetwater and WeberCreeks, El Dorado County, Pit River,Shasta County, Russian River, SonomaCounty, and Little Lake Valley,Mendocino County; and upper PutahCreek, in Yolo County

Nests in dense riparian habitatsdominated by willows, alders, Oregonash, tall weeds, blackberry vines, andgrapevines

Loss of riparian breeding habitat None for nesting; no nesting records; nosuitable nesting habitat; occasionalmigrant

Tricolored blackbirdAgelaius tricolor

SC/SSC Largely endemic to California;permanent residents in the CentralValley from Butte County to KernCounty; at scattered coastal locationsfrom Marin County south to San DiegoCounty; breeds at scattered locations inLake, Sonoma, and Solano Counties;rare nester in Siskiyou, Modoc, andLassen Counties

Nests in dense colonies in emergentmarsh vegetation such as tules andcattails or upland sites with blackberries,nettles, thistles, and grainfields; nestinghabitat must be large enough to support50 pairs; probably requires water at ornear the nesting colony; requires largeforaging areas, including marshes,pastures, agricultural wetlands, dairies,and feedlots where abundant insect preyare available

Loss of wetland and upland breedinghabitats from conversion to agricultureand urban development and to waterdevelopment projects; pesticidescontamination; human disturbance ofnesting colonies

None for nesting; no records; no suitablenesting habitat; occasional visitor; noneobserved during field survey

Reptiles

Northwestern pond turtleClemmys marmorata marmorata

SC/SSC In California, range extends from Oregonborder of Del Norte and SiskiyouCounties south along coast to SanFrancisco Bay, inland throughSacramento Valley, and on the westernslope of Sierra Nevada; range overlaps

Woodlands, grasslands, and openforests; occupies ponds, marshes, rivers,streams, and irrigation canals withmuddy or rocky bottoms and withwatercress, cattails, water lilies, or other

Loss and alteration of aquatic andwetland habitats; habitat fragmentation

Known to occur in the Arboretum andSouth Fork of Putah Creek




Statusa


with that of southwestern pond turtlethrough the Delta and Central Valley toTulare County

aquatic vegetation

Giant garter snakeThamnophis gigas

T/T Central Valley from Fresno north to theGridley/Sutter Buttes area; has beenextirpated from areas south of Fresno

Sloughs, canals, and other small water-ways where there is a prey base of smallfish and amphibians; requires grassybanks and emergent vegetation forbasking and areas of high groundprotected from flooding during winter

Loss of habitat from agriculture andurban development

Low; observed in the South Fork ofPutah Creek within 1 mile of Old DavisRoad during 1976 (Natural DiversityData Base 1995); no suitable habitatexists along the North Fork of PutahCreek

Amphibians

California red-legged frogRana aurora draytoni

T/SSC Found along the coast and coastalmountain ranges of California fromHumboldt County to San DiegoCounty, and formerly in the SierraNevada foothills and midelevations fromButte County to Fresno County

Permanent and semipermanent aquatichabitats, such as creeks and cold waterponds, with emergent and submergentvegetation and riparian species along theedges; may estivate in rodent burrows orcracks during dry periods

Alteration of stream and wetlandhabitats, over harvesting (historically),habitat destruction, and competition andpredation by fish and bullfrogs

None; no records; extirpated from theSacramento Valley (Geer pers. comm.)

Insects

Valley elderberry longhorn beetleDesmocerus californicus dimorphus

T/-- Streamside habitats below 3,000 feetthrough the Central Valley of California

Riparian and oak savanna habitats withelderberry shrubs; elderberries are hostplants

Loss and fragmentation of riparianhabitats

High; no records; suitable habitat existsalong the North Fork of Putah Creekbetween Highway 113 and theArboretum, the South Fork of PutahCreek along the Southern PacificRailroad, and in developed areas

Delta June beetlePolyphylla stellata

SC/-- Sacramento-San Joaquin River Deltaregion

Sand deposits along riverine habitats Alteration of riverine habitats Low; no records; low to moderatepotential habitat along Putah Creek andthe South Fork of Putah Creek; nosuitable habitat along the North Fork ofPutah Creek

Sacramento Valley tiger beetleCicindela hirticollis abrupta

SC/-- Lower Sacramento Valley (i.e.,Sacramento River, lower AmericanRiver, and Cache Creek)

Found in sandy areas among willows inriverine and riparian habitats

Alteration of valley streams Low to moderate; no records; suitablehabitat exists along the South Fork ofPutah Creek; no suitable habitat alongthe North Fork of Putah Creek

Sacramento anthicid beetleAnthicus sacramento

SC/-- Restricted to a dune area at mouth ofSacramento River; western tip of GrandIsland, Sacramento County; dunes nearRio Vista, Solano County; Ord FerryBridge, Butte County; upper PutahCreek

Found in sand slip-faces among willows Alteration of delta dunes; limited range Low to moderate; no records; suitablehabitat exists along the South Fork ofPutah Creek; no suitable habitat alongthe North Fork of Putah Creek

Ancient antSmithistruma reliquia

SC/-- Yolo County Riparian valley oak woodland Loss and fragmentation of riparianwoodlands; displacement by non-nativeants

None; no records; no suitable habitat

Valley oak ant SC/-- Isolated locations throughout California, Riparian valley oak woodland Loss and fragmentation of riparian None; no records; no suitable habitat




Statusa


Proceratium californicum including Yolo County woodlands; displacement by non-nativeants

Antioch multilid waspMymosula pacifica

SC/-- Unknown range; generally in theSacramento-San Joaquin River Deltaregion

Sand deposits along riverine habitats Alterations along valley and Deltariverine habitats

Low to moderate; no records; suitablehabitat exists along the South Fork ofPutah Creek; no suitable habitat alongthe North Fork of Putah Creek

_______________aStatus definitions:

Federal

E = listed as endangered under the federal Endangered Species Act.

T = listed as threatened under the federal Endangered Species Act.

PE = proposed for listing as endangered under the federal Endangered Species Act.

SC = species of concern to the U.S. Fish and Wildlife Service (Noda pers. comm.).

MNBMC = migratory nongame birds of management concern to the U.S. Fish and Wildlife Service.

-- = no designation.

State

E = listed as endangered under the California Endangered Species Act.

T = listed as threatened under the California Endangered Species Act.

FP = fully protected under the California Fish and Game Code.

SSC = species of special concern.

-- = no designation.


Swainson’s hawks usually nest in large, mature trees. Native trees (e.g., valley oaks, Fremont’scottonwoods, black walnuts, and willows) are almost always used, although nests have been found in non-native eucalyptus trees and ornamental conifers (California Department of Fish and Game 1994).

Swainson’s hawks forage in large, open plains and grassland habitats. Hay, grain, and most rowcrops provide suitable Swainson’s hawk foraging habitat during at least part of the breeding season. Otheragricultural crops, such as those in vineyards and orchards, do not provide suitable foraging habitat becausethe hawks cannot maneuver through rows of trees and vines (California Department of Fish and Game1994).

Conversion of native grassland and woodland communities to agricultural uses is one of the primarycauses for the decline of the Swainson’s hawk. Remaining populations of Swainson’s hawks have shiftedinto areas that continue to provide suitable nesting habitat and have suitable agricultural foraging habitats(e.g., alfalfa and other hay crops) and grasslands in close proximity. Suitable nesting and foraging habitatcontinues to be eliminated throughout the Central Valley, primarily as a result of urban development,incompatible agricultural practices, and flood control projects.

The occurrence of the Swainson’s hawk in and around the Campus is well documented. TheCampus is currently conducting annual surveys for Swainson’s hawk nests on the Campus and within 0.5mile of the Campus. These surveys documented 22 nests in 1992, 18 in 1993, 23 in 1994, and 30 in 1996(England pers. comm.). Many of the nests are located along the Main Fork, South Fork, and North Forkof Putah Creek, including the Arboretum Waterway (Figure 4.4-1). There is also one Swainson’s hawknest along Old Davis Road near Interstate 80.

The agricultural fields on and adjacent to Campus are suitable foraging habitats for the Swainson’shawk.

Burrowing Owl. The burrowing owl is a migratory nongame bird of management concern toUSFWS, and is a state species of special concern. Nesting burrowing owls are protected under theCalifornia Fish and Game Code Section 3503.5 and federal Migratory Bird Treaty Act. The burrowingowl occurs in a variety of open habitats, including grasslands and agricultural fields. The owls nest inburrows excavated by rodents, particularly the California ground squirrel. Although cultivated agriculturalfields are unsuitable nesting habitat for burrowing owls, the owls often nest along the borders of agriculturalfields and along the levees or outer banks of agricultural drainages and water delivery channels.

In 1995, the Raptor Center staff released two fledgling burrowing owls at the Raptor Center’sonsite artificial burrowing owl nest mound, which is in the southeast corner of the Raptor Center adjacentto the southern end of the South Campus storm water drainage ditch. In 1996, at least one of thesereleased owls mated with a wild burrowing owl and reared four young along the drainage ditch adjacentto the eastern side of the Raptor Center (Figure 4.4-1) (Brooks and Morzenti pers. comms.). The artificialburrowing owl nest mound is in the Raptor Center facility, but the drainage ditch is adjacent to the facility. These owls do not receive the same level of legal protection as wild owls (Scoonover pers. comm.). Noother burrowing owls were found during project surveys.


Loggerhead Shrike . The loggerhead shrike is a state species of special concern. The loggerheadshrike was formerly a Category 2 candidate for federal listing as threatened or endangered, but theCalifornia subspecies were removed from the list. The loggerhead shrike is a resident species throughoutthe lowlands and foothills of California. Shrikes nest in low trees and dense shrubs, and forage ingrasslands, agricultural fields, and oak savannas.

Suitable shrike nesting habitat exists along the South Fork of Putah Creek. There are no recordsof the loggerhead shrike nesting in the project area (EIP Associates 1994, Natural Diversity Data Base1995). No loggerhead shrikes were seen during the field surveys.

Northwestern Pond Turtle. The northwestern pond turtle is a state species of special concern. Ponds and slow-moving streams provide suitable rearing and foraging habitat and cover for pond turtles. Pond turtles lay their eggs in upland areas, such as scrub, grassland, and savanna habitats. Pond turtlepopulations have declined because of the loss of and degradation to wetlands, streams, and adjacent uplandhabitats.

The South Fork of Putah Creek provides suitable aquatic habitat for pond turtles. Northwesternpond turtles have been observed in the South Fork of Putah Creek. The WWTP outfall contributes asubstantial amount of water to the South Fork of Putah Creek, which supplements pond turtle habitat,especially during the summer and fall when upstream flows are reduced.

Giant Garter Snake. The giant garter snake is listed as a threatened species under the federaland California ESAs. Giant garter snakes occur in the Central Valley from Fresno County to Butte County. They are found in sloughs and wetlands with emergent vegetation, grassy banks, or blackberry thickets. During the winter, giant garter snakes hibernate in upland habitats. Giant garter snake populations havedeclined from wetland habitat loss and fragmentation and disturbance in adjacent upland habitats. TheSouth Fork of Putah Creek is considered low- to marginal-quality habitat for giant garter snakes. One giantgarter snake was observed in the South Fork of Putah Creek within 1 mile of the Old Davis Road in 1976(Natural Diversity Data Base 1995), but the population is presumed to be extirpated (U.S. Fish and WildlifeService 1993).

Valley Elderberry Longhorn Beetle. The VELB is listed as a threatened species under thefederal ESA. The VELB requires its host plant, the elderberry shrub, for feeding and reproduction. USFWS considers all elderberry shrubs in the Central Valley with stems 1 inch or greater at ground levelas potential VELB habitat (U.S. Fish and Wildlife Service 1994). Elderberry shrubs were observed alongthe Southern Pacific Rail Road right-of-way (Figure 4.4-2), at the parking lot of the Oncology Laboratory,and near the drainage ditch adjacent to the proposed replacement pasture. Two potential exit holes wereobserved on one elderberry shrub along the railroad. Table 4.4-3 shows the number of stems 1 inch orgreater for each shrub and the presence or absence of VELB exit holes. An additional seven elderberryshrubs or clusters were observed along the north levee or adjacent to the north levee of Putah Creek.


Table 4.4-3. Elderberry Shrub and Valley Elderberry Longhorn Beetle Data

Elderberry Shrub NumberNumber of Stems 1 inch or

GreaterPresence or Absence of VELB

Exit Holes and Comments

1 1 None

2 2 None

3 2 None

4 1 None

5 1 None

6 6 None

7 5 None

8 None; sprouting from stump None

9 6 2 potential old exit holes

10 6 None; in a parking lot

11 4 None

12-18 undetermined Not surveyed for exit holes


Delta June Beetle. The delta June beetle is a federal species of concern. The range of this beetleis unknown, but generally it occurs in the Sacramento/San Joaquin Delta region. This beetle occurs in sanddeposits along riverine habitats. Alterations of riverine habitats in the lower Sacramento Valley and theDelta have contributed to its decline.

The South Fork of Putah Creek is considered suitable habitat for the Delta June Beetle.

Sacramento Valley Tiger Beetle. The Sacramento Valley tiger beetle is a federal species ofconcern. This subspecies has limited local occurrence throughout the Sacramento Valley, with specimensreported from along the Sacramento and American Rivers and Cache Creek. The Sacramento Valley tigerbeetle occurs on sand deposits associated with aquatic habitats. Adults tend to hunt along the shoreline,attacking other insects that come to drink. Larvae reside in burrows much farther up the bank. TheSacramento Valley tiger beetle’s sparse distribution may be caused in part by the alteration of variousstreams that prevent sandy-shore deposition or keep existing habitat inundated.

The Sacramento Valley tiger beetle has been recorded along the Sacramento River below theconfluence with the American River and along the lower American River. There are no records of theSacramento Valley tiger beetle in the project area (Natural Diversity Data Base 1995). There is low- tomoderate-quality potential habitat along the Main and South Forks of Putah Creek (University of California,Davis 1994).

Sacramento Anthicid Beetle. The Sacramento anthicid beetle is a federal species of concern. It is a terrestrial beetle found in sandy habitats, usually along riparian areas, or similar aquatic habitats. Thisbeetle is probably a scavenger (Arnold 1990), feeding on debris that collects on sandy shores. Firstdescribed from Grand Island in Sacramento County, the Sacramento anthicid beetle has been collectedfrom along the Sacramento River, from its mouth to Butte County (Chandler 1978, Arnold 1990), andalong Putah Creek in the Lake Berryessa area (Arnold 1990).

The Sacramento anthicid beetle is a terrestrial beetle found along sandy shores on the slip facesalong willows and arundo. The beetle needs dry, sandy areas in riparian areas or similar aquatic habitats(Hagen 1986).

The restriction of the Sacramento anthicid beetle’s range was caused in part by the damming ofwatercourses. The known Putah Creek population no longer exists because the construction of Monticellodam allowed for the continuous inundation of the sandy habitat normally used by the beetle (Arnold 1990).

There are no records of the Sacramento anthicid beetle in the project area (Natural Diversity DataBase 1995). There is low- to moderate-quality potential habitat along Putah Creek (EIP Associates 1994).

Antioch Multilid Wasp. The Antioch multilid wasp is a federal species of concern. The rangeof this wasp is unknown, but generally it occurs in the Sacramento/San Joaquin Delta region. This waspoccurs in sand deposits along riverine habitats. Alterations of riverine habitats in the lower SacramentoValley and the Delta have contributed to its decline.


The South Fork of Putah Creek is considered suitable habitat for the Antioch multilid wasp.

REGULATORY SETTING

Federal and state regulations that may relate to resources present at the project site are describedbelow.

Federal Regulations

Section 404 of the Clean Water Act

The Corps and the U.S. Environmental Protection Agency (EPA) regulate the discharge of dredgedand fill material into “waters of the United States” under Section 404 of the Clean Water Act (CWA).

Corps jurisdiction over nontidal “waters for the United States” extends to the “ordinary high watermark provided the jurisdiction is not extended by the presence of wetlands” (33 CFR Part 328 Section328.4). The Corps will typically exert jurisdiction over that portion of the project site that contains watersof the United States and adjacent or isolated wetlands. In general, this translates to the bank-to-bankportion of a creek along its entire length, up to the ordinary high-water mark, and adjacent wetland areasthat will be adversely affected by a proposed project.

Federal Endangered Species Act

The federal ESA prohibits the “take” of endangered or threatened wildlife species. Take is definedto include harassing, harming (includes significantly modifying or degrading habitat), pursuing, hunting,shooting, wounding, killing, trapping, capturing, or collecting wildlife species or any attempt to engage insuch conduct (16 U.S. Government Code [USC] 1532, 50 CFR 17.3). Actions that result in a taking canresult in civil or criminal penalties.

The federal ESA and EPA Section 404 guidelines prohibit the issuance of wetland permits forprojects that would jeopardize the existence of a threatened or endangered wildlife or plant species. TheCorps must consult with USFWS when threatened or endangered species may be affected by a proposedproject to determine whether issuance of a Section 404 permit would jeopardize the species.

State Regulations


California Endangered Species Act

The state ESA is similar to the federal ESA but pertains to state-listed endangered and threatenedspecies. It requires state agencies to consult with DFG when preparing CEQA documents in order toensure that the state lead agency actions do not jeopardize the existence of listed species. It directsagencies to consult with DFG on projects or actions that could affect listed species, directs DFG todetermine whether jeopardy would occur, and allows DFG to identify “reasonable and prudent alternatives”to the project consistent with conserving the species. An agency can approve a project that affects a listedspecies if the agency determines that there are “overriding considerations”; however, agencies are prohibitedfrom approving projects that would cause the extinction of a listed species.

Mitigating impacts on state-listed species involves avoidance, minimization, and compensation(listed in order of preference). Unavoidable impacts on state-listed species are typically addressed in adetailed mitigation plan based on DFG guidelines.

DFG exercises authority over mitigation projects involving state-listed species, including thoseresulting from CEQA mitigation requirements. DFG requires preparation of mitigation plans in accordancewith published guidelines.

The state ESA prohibits the taking of state-listed endangered or threatened plant and wildlifespecies. DFG may authorize taking if an approved habitat management plan or management agreement thatavoids or compensates for possible jeopardy is implemented.

Section 1601 Streambed Alteration Agreements

Under Chapter 6 of the California Fish and Game Code, DFG is responsible for the protection andconservation of the state’s fish and wildlife resources. Section 1601 of the code defines the responsibilitiesto DFG and requirements of public applicants to obtain an agreement to “divert, obstruct, or change thenatural flow or bed, channel, or bank of any river, stream, or lake designated by the department in whichthere is at any time an existing fish or wildlife resources or from which those resources derive benefit, or willuse material from which the streambeds designated by the department”.

The local warden or unit biologist typically has responsibility for issuing Section 1601 agreements. These agreements usually include specific requirements related to construction techniques and remedial andcompensatory measures to mitigate adverse impacts. DFG also may request long-term monitoring as partof a Section 1601 agreement in order to assess the effectiveness of the proposed mitigation.





n result in substantial, or potentially substantial, adverse change in the native flora or fauna,including candidate species and DFG “Species of Special Concern” from conversion of existinghabitat to urban uses or disturbance of areas currently supporting such species;

n result in the “take” (defined as kill, harm, or harassment) of any listed threatened or endangeredspecies or the habitat of such species;

n result in the substantial reduction in acres of habitat (including wetlands) of native plants,wildlife, or fish;

n interfere substantially (creation of barriers to the free movement between habitats both locallyand regionally) with the movement of any resident or migratory wildlife or fish species; or

n be in conflict with existing state or federal natural resource protection laws, policies, orguidelines.

The fisheries analysis also determines that the project will have a significant effect on theenvironment if it will:

n result in a substantial reduction in fish populations because of increased mortality or

n result in a substantial change in habitat availability and suitability that affects a species survival,growth, migration, and reproduction.


Agricultural Lands and Ruderal/Annual Grassland

4.4-1 Development of the proposed WWTP would result in the conversion of approximately 20acres of agricultural lands (pasture) and approximately 0.3 acre of ruderal/annualgrassland to urban uses and could result in the loss of special-status plant species. Thisimpact is considered potentially significant.

The 1994 LRDP EIR identifies the following mitigation measures that apply to the project.


4.7-1(a) During the project planning phase, the Campus shall conduct a rareplant survey if the site was previously undeveloped. Surveys shall beconducted by qualified biologists in accordance with the most currentDFG/USFWS guidelines or protocols and shall be conducted at the timeof year when the plants in question are identifiable. (Identificationperiods are included in Table 4.7-1 of the 1994 LRDP EIR, however,survey timing for the various plant species is dependent in part on yearlyrainfall patterns and is determined on a case-by-case basis.)

4.7-1(b) Based on the results of the survey, prior to design approval, theCampus in consultation with DFG and/or USFWS, shall determinewhether the project would result in a significant impact to any special-status plant species. Evaluation of project impacts shall consider thefollowing:

n The status of the species in question (e.g., officially listed bythe State or Federal Endangered Species Acts, candidate species,CNPS list).

n The relative density and distribution of the on-site occurrenceversus typical occurrences of the species in question.

n The habitat quality of the on-site occurrence relative tohistoric, current or potential distribution of the population.

If these surveys reveal no occurrences of any species, or if theCampus in consultation with DFG or USFWS determines that nosignificant impacts on any special-status plant species would resultfrom project implementation, then no further mitigation would berequired.

Should one or more of special-status plant species occur on theproject site, and a determination of significant impact be made, thefollowing mitigation measure shall be required.

4.7-1(c) Prior to design approval, the Campus in consultation with the DFGand/or the USFWS, shall prepare and implement a mitigation plan, inaccordance with any applicable State and/or Federal statutes or laws,that reduces impacts to a less-than-significant level.

Development of the proposed project would result in the conversion of approximately 20 acres ofpasture and 0.3 acre ruderal/annual grassland to urban development as a result of the construction of theproposed WWTP. Pasture and ruderal/annual grassland habitats are common and abundant locally,


regionally, and statewide and their loss of is not considered significant; however, there is the potential foroccurrence of special-status plant species in this habitat type.

In compliance with this mitigation measure, a rare plant survey for the project was conducted onApril 24, 1996. No special-status plant species were observed; therefore, no impacts would occur.

Mitigation Measure


4.4-2 Development of the proposed WWTP would result in the conversion of approximately 20acres of agricultural lands (pasture) and approximately 0.3 acre of ruderal/annualgrassland to urban uses and would result in the loss of wildlife habitat for resident andmigratory wildlife species. This impact is considered less than significant.

As stated in the “Environmental Setting” section, many species use agricultural land andruderal/annual grassland for food and cover. These species include red-tailed hawks, northern harriers,white-tailed kites, and great-horned owls, in addition to western meadowlarks, American pipits, andmourning doves. The loss of approximately 20 acres of agricultural lands would not result in a substantialadverse change in abundance of these species.

Mitigation Measure


4.4-3 Realignment or rerouting of the drainage canal east of the Raptor Center could harm theburrowing owls nesting along the banks of the canal. This impact is considered potentiallysignificant.


4.7-3(b) The Campus, in consultation with the DFG, shall conduct a pre-construction breeding-season survey (approximately February 1 throughAugust 31) of proposed project sites during the same calendar year thatconstruction is planned to begin. The survey shall be conducted by aqualified biologist to determine if any burrowing owls are nesting on ordirectly adjacent to any proposed project site.

If phased construction procedures are planned for the proposedproject, the results of the above survey shall be valid only for theseason when it is conducted.

4.7-3(c) During the construction stage, the Campus, in consultation with theDFG, shall avoid all burrowing owl nest sites potentially disturbed by


project construction during the breeding season while the nest is occupiedwith adults and/or young. The occupied nest site shall be monitored bya qualified biologist to determine when the nest is no longer used. Avoidance shall include the establishment of a 300-foot to 500-footdiameter non-disturbance buffer zone around the nest site. Disturbanceof any nest sites shall only occur outside of the breeding season and whenthe nests are unoccupied based on monitoring by a DFG approvedbiologist. The buffer zone shall be delineated by highly visible temporaryconstruction fencing.

Based on approval by DFG, pre-construction and pre-breedingseason exclusion measures may be implemented to precludeburrowing owl occupation of the project site prior to project-relateddisturbance.

In compliance with the 1994 LRDP EIR Mitigation Measure 4.7-3, potential impacts of the projecton burrowing owls were evaluated. The proposed WWTP site and influent pipeline are unsuitable nestinghabitat for burrowing owls, and no burrowing owls or potential dens were seen during the field survey. Noburrowing owls or potential dens were seen along the proposed effluent pipeline route, along Old DavisRoad, or along the railroad right-of-way. No burrowing owls were observed nesting during the 1995 and1996 surveys, except along the existing drainage ditch along the eastern property boundary. If a newchannel is created but the old channel remains undisturbed, no impacts to the owls would occur, and nomitigation would be required. If the existing canal is removed or realigned as part of the WWTP project,however, the owls could be harmed by construction activities, and mitigation would, therefore, be required.A preconstruction survey is required in the same calendar year that construction will occur.

Mitigation Measure

Implementation of the following mitigation measure would reduce this impact to a less-than-significant level if the burrowing owls could be harmed by realignment or removal of the drainage channel.

4.4-3(a) The Campus shall conduct a non-breeding season survey (approximately August 1through January 30) of the drainage ditch before construction. If no burrowing owlsare present, the Campus will destroy (i.e., collapse) all potential nesting burrows toprevent owls from returning to the site. The Campus will monitor the banks of theditch biweekly to ensure that no new burrows are created that could be used by owlsbefore construction begins. New burrows will be destroyed until construction begins. (Scoonover pers. comm.)

4.4-3(b) If the non-breeding season survey reveals the presence of owls, the Campus willensure that the owls will not be trapped in burrows in the area during constructionby displacing them from the area. One-way exit doors will be placed at the entrancesof the occupied and potential burrows that will be destroyed to ensure that the owls


can exit from the burrows but cannot return to them. The one-way doors shall beinstalled at least 48 hours before the burrows are destroyed to ensure that the owlshave left the burrows. The burrows shall then be dug out by hand to ensure that noowls remain in them. This measure shall be completed outside the February 1through August 1 nesting season.

4.4-3(c) To compensate for the loss of nesting sites, the Campus shall construct two artificialnest burrows for each active burrow eliminated by the project. The artificial nestburrows would be constructed in the vicinity of the existing ditch. The artificial nestburrows could be placed along the banks of the new channel, or at the newwastewater treatment plant if operation of the facility would not affect the owls. Ifplacing the artificial nest burrows in these areas is not feasible, a suitable locationwill be identified in conjunction with DFG.

4.4-3(d) When the mitigation and monitoring is completed, the Campus shall prepare andsubmit to DFG a letter describing the methods, results, and conclusions of theburrowing owl mitigation and monitoring efforts.

4.4-4 Development of the proposed WWTP would result in the conversion of approximately 20acres of agricultural lands (pasture) and approximately 0.3 acre of ruderal/annualgrassland to urban uses, which could result in the loss of nesting habitat for raptors (birdsof prey). This impact is considered potentially significant.


4.7-4(a) The Campus shall conduct a pre-construction or pre-tree pruning orremoval survey of trees greater than 30-feet tall (proposed activity)during the raptor breeding-season (approximately March 1 throughAugust 31). The survey shall be conducted by a qualified biologist duringthe same calendar year that the proposed activity is planned to begin todetermine if any nesting birds-of-prey would be affected.

If phased construction procedures are planned for the proposedactivity, the results of the above survey shall be valid only for theseason when it is conducted.

If the above survey does not identify any nesting raptor species within the area affected by theproposed activity, then no further mitigation would be required. However, should any nesting raptor speciesbe found, the following mitigation measure from the 1994 LRDP EIR shall be implemented.

4.7-4(b) The Campus shall continue to conduct annual surveys to determinethe location of nesting Swainson’s hawks on the Campus. If nestingSwainson’s hawks are found during the survey at a previously unknown


location within one-half mile of a project site and not within 100 yardsof a previously documented site, the Campus shall, prior to projectconstruction, contact the California Department of Fish and Game todetermine the potential for disturbance to nesting Swainson’s hawks andwill implement feasible changes in the construction schedule or otherappropriate adjustments to the project in response to the specificcircumstances.

If, after five years, a previously recorded nest site remainsunoccupied by a Swainson’s hawk, it will no longer be considered asa Swainson’s hawk nest site subject to this mitigation.

As described in the “Environmental Setting” section, many species of resident and migratory raptorsbesides burrowing owls have been observed on the Campus during the breeding season and thereforeprobably use the ruderal/annual grassland vegetation in vacant fields or unmaintained field edges for nesting. Removal of trees or tree pruning could also remove active nests for such species as the red-tailed hawk,red-shouldered hawk, white-tailed kites, or American kestrel. Pursuant to Section 3503.5 of the Fish andGame Code of California:

It is unlawful to take, possess, or destroy any birds in the orders Falconiformes or Strigiformes(birds-of-prey) or to take, possess, or destroy the nest or eggs of any such bird except asotherwise provided by this code or any regulation adopted pursuant thereto.

In compliance with the 1994 LRDP EIR Mitigation Measure 4.7-4, potential impacts of the projecton nesting raptors were evaluated. Potential loggerhead shrike and white-tailed kite nesting habitat existsalong the South Fork of Putah Creek; however, no suitable loggerhead shrike or kite nesting habitat wouldbe removed by the project. A preconstruction survey is required in the same calendar year thatconstruction will occur. Implementing this survey as part of the project would ensure that development ofthe project would result in a less-than-significant impact.

Mitigation Measure


4.4-5 Development of the proposed WWTP would result in the conversion of approximately 20acres of agricultural lands (pasture) and approximately 0.3 acre of ruderal/annualgrassland to urban uses, which would result in the loss of foraging habitat for Swainson’shawk. This impact is considered potentially significant.

The 1994 LRDP EIR identifies the following mitigation measure that applies to the project.

4.7-5 As Agricultural Land and Ruderal/Annual Grassland is converted to Campusdevelopment under the 1994 LRDP, the Campus will compensate for the lossof Swainson’s hawk foraging habitat at a 1:1 ratio of acres lost to acres


preserved through the implementation of one or a combination of thefollowing methods.

n Approximately 40 acres of Cropland habitat in the "C" tract adjacentto the Putah Creek Reserve on the West Campus will remain Campusagricultural research uses but will be under land use restrictions that willensure cropland cover types that are suitable as Swainson’s hawkforaging habitat. No incompatible uses such as orchards, vineyard, ordevelopment will be allowed in the areas set aside for Swainson’s hawkforaging habitat. However, normal crop rotations may periodically resultin unsuitable cover types of annual crops.

n Approximately 20 acres of land within the North Fork Cutoffthat currently support livestock enclosures will be restored to awoodland and grassland habitat.

n Approximately 55 acres of existing orchards adjacent to Putah Creekat the Russell Ranch will be removed, converted to a cover type suitablefor Swainson’s hawk foraging, and added to the Putah Creek Reserve.

n Approximately 85 acres at the Russell Ranch that have beendesignated as a habitat restoration and research area will include theestablishment of cover types that are suitable Swainson’s hawk foraginghabitat.

Construction of the proposed WWTP would eliminate approximately 20 acres of suitable andoccupied foraging habitat. This impact was considered significant in the 1994 LRDP EIR because theSwainson’s hawk is listed as threatened under the California ESA and the loss of foraging habitat couldcontribute to the species’ decline. Implementation of Mitigation Measure 4.7-5 as required in the 1994LRDP EIR would reduce this impact to a less-than-significant level.

Mitigation Measure


4.4-6 Development of the proposed WWTP could result in the potential failure of Swainson’shawk nesting efforts. This impact is considered potentially significant.


4.7-6(a) The Campus shall conduct a pre-construction breeding season surveyof the proposed project site, and within a one-half-mile radius of the site,to determine the presence or absence of any nesting Swainson’s hawks.


If any Swainson’s hawks are nesting within a one-half-mile radius ofthe project site, the Campus shall, in consultation with DFG,determine the potential for disturbance to nesting Swainson’s hawksand will implement feasible changes in the construction schedule orother appropriate adjustments to the project in response to thespecific circumstances.

4.7-6(b) The Campus shall continue to conduct annual surveys to determinethe location of nesting Swainson’s hawks on and within ½ mile of theCampus. If nesting Swainson’s hawks are found during the survey at apreviously unknown location within one-half mile of a project site andnot within 100 yards of a previously documented site, the Universityshall, prior to project construction, contact the California Department ofFish and Game to determine the potential for disturbance to nestingSwainson’s hawks and will implement feasible changes in theconstruction schedule or other appropriate adjustments to the project inresponse to the specific circumstances.


DFG has established a 0.5-mile radius around known Swainson’s hawk nests as a zone wherepotential disturbances could disrupt nesting efforts. In many instances, Swainson’s hawks are tolerant ofhuman activity; however, construction-related activities could cause nest abandonment and nesting failureby nesting Swainson’s hawks. Swainson’s hawk nest sites 1-4, 6, and 7 are not likely to be adverselyaffected by construction activities because these nesting pairs of Swainson’s hawks are accustomed totraffic, agricultural activities, and human activity and these nests are at sufficient distance from potentialconstruction areas. Swainson’s hawk nest site 5 is immediately along Old Davis Road and near Interstate80. Although these birds are also accustomed to human activity, they nest within line-of-sight of the influentpipeline construction and are about 150 feet from the construction area for the proposed project. This nest,if active during construction, could be disturbed by construction activities. This impact is consideredsignificant because the Swainson’s hawk is listed as threatened under the California ESA and directmortality and nesting failure could occur as a result of project implementation.

In compliance with 1994 LRDP EIR Mitigation Measure 4.7-6(a), the Campus shall conduct apre-construction breeding season survey of the proposed project site. Also, in compliance with 1994LRDP EIR Mitigation Measure 4.7-6(b), the Campus shall continue to conduct annual surveys to determinethe location of nesting Swainson’s hawks on and within 0.5 mile of the Campus.

Mitigation Measure


Implementation of the following mitigation measure would reduce this impact to a less-than-significant level.

4.4-6 The Campus shall determine whether the Swainson’s hawk nest site 5 located near Old DavisRoad and Interstate 80 is active during construction. If it is active, the Campus will eitherconstruct the pipeline during the Swainson’s hawk non-breeding season (September-February) or implement other feasible changes to the project in consultation with DFG toavoid site disturbance.

4.4-7 Construction of the proposed WWTP could result in the disturbance of potential habitatfor the VELB. This impact is considered potentially significant.


4.7-7 During the project design stage and as a condition of project approval, theCampus shall:

(a) Conduct a project-specific survey for all potential VELB habitat,including a stem count and an assessment of historic or current VELBuse;

(b) Avoid and protect all potential VELB habitat within a natural openspace area where feasible; and

(c) Where avoidance is infeasible, develop and implement a VELBmitigation plan in accordance with the most current USFWS mitigationguidelines for unavoidable take of VELB habitat pursuant to eitherSection 7 or Section 10(a) of the Federal Endangered Species Act.

In compliance with 1994 LRDP EIR Mitigation Measure 4.7-7(a), a project-specific survey wasconducted to identify VELB habitat. Potential VELB habitat exists along the SPRR tracks, the fence lineof the proposed WWTP site, the parking lot of the CCEHP, along the South Fork of Putah Creek, and thedrainage ditch just east of the LEHR/SCDS area. Implementation of the project would not require theremoval of elderberry shrubs, but several elderberry shrubs could be disturbed during construction orrealignment of the effluent pipeline and drainage channel (Figure 4.4-1). Elderberry shrubs 1 through 9could be affected by construction activity during construction of the effluent pipeline under the SouthernPacific Railroad. Elderberry shrubs 11 through 16 could be affected by construction activity duringpotential rerouting of the drainage channel. If the Oncology Laboratory parking lot is used as a staging areaduring construction, elderberry shrub 10 could be damaged by construction vehicles. If the levee road westof Old Davis Road is used as a staging area during construction, elderberry shrubs 17 and 18 could bedamaged. Clearing elderberry shrubs or destroying VELB habitat could constitute “take” under the federalESA, which prohibits take of a protected species; take is defined as harassment, harm (including disturbing


occupied habitat), or capture. This impact is considered potentially significant because it is not possible todetermine exact impacts without final construction drawings and VELB is a federally protected species.

Mitigation Measure


4.4-7 The Campus shall include in the construction plans and specifications the followingprotection measures, which will be implemented prior to the initiation of any constructionactivities.(a) Temporary construction fencing shall be placed at least 20 feet outside the dripline

of elderberry shrubs 1 through 18 during the VELB breeding season (April-June). After or before the breeding season, the fencing could be moved to 5 feet beyond thedripline, if needed. The fencing will remain in place until construction is complete. All fencing will be done under direct supervision of a qualified biologist.

(b) The fence shall be posted with a sign that reads as follows: “This area is potentialhabitat of the valley elderberry longhorn beetle, a threatened species, and must notbe disturbed. This species is protected by the federal Endangered Species Act of1973, as amended. Violators are subject to prosecution, fines, and imprisonment”.

(c) The buffer zone within the fence shall remain off-limits to construction activities,vehicles, wastes, or construction materials.

(d) The fence shall remain in place until final construction is complete.

(e) Dust-reducing construction measures will be used to minimize the amount of dustnear the shrubs. These measures include minimizing the amount of time surfaces areexposed, sprinkling exposed areas and soil piles with water periodically, andcovering soil piles with plastic sheets or tarpaulins to limit disturbance.

Riverine and Open Water Pond

4.4-8 The proposed project (possible reconstruction of the effluent outfall or relocation of thedrainage ditch) could result in the loss or adverse modification of wetlands or other watersof the U.S. that fall under the jurisdiction of the Corps and/or DFG. This impact isconsidered potentially significant.



4.7-8(a) During the project design phase, the Campus shall conduct a wetlanddelineation of the project site. The wetland delineation shall be verifiedby the Corps.

4.7-8(b) The Campus shall obtain an individual permit, written authorizationunder an existing nationwide permit, or a written response stating thatno further action is required, from the Corps prior to the filling or otheradverse modification of any Corps-verified delineated wetland habitats.

4.7-8(c) The Campus shall submit an application for a Streambed AlterationAgreement to DFG at least 30 days prior to any alteration, filling, ormodification of the channel, bed, or bank of Putah Creek, South Fork ofPutah Creek, or any other natural drainage with a distinct channel.

The proposed project could require replacement of the existing effluent outfall in the South Forkof Putah Creek or the relocation of the existing drainage ditch at the east side of the SCDS/LEHR area. If taken, either of these actions would require the Campus to implement the 1994 LRDP MitigationMeasures 4.7-8(a) and (c) and obtain a Section 404 permit or a streambed alteration agreement.

Mitigation Measure


4.4-9 The proposed project would result in an increase in the amount of water discharged to theSouth Fork of Putah Creek, which would result in an increase in stream flows that couldaffect special-status riverine invertebrates. This impact is considered less thansignificant.

The Sacramento Valley tiger beetle, Sacramento anthicid beetle, and Antioch multilid wasp couldoccur in the sand deposits along the South Fork of Putah Creek. The contribution of flows to the creekwould increase with the proposed project. The increase in stream flows along the South Fork would notsubstantially impact sand deposits that could support special-status invertebrates; therefore, the impacts onthese invertebrates are considered less than significant.

Mitigation Measure


Urban Landscaping


4.4-10 Construction of the proposed project (pipeline along Old Davis Road) could result indamage to mature planted black walnuts. This impact is considered less than significantbecause these trees do not have significant botanical or wildlife value.

Replacing or realigning the effluent pipeline paralleling Old Davis Road would not require theremoval of the planted black walnuts, but the trees could be inadvertently damaged by constructionequipment, which could adversely affect the long-term health of the trees. Although long-term effects onthe trees are not considered a significant biological impact, damage to these trees should be minimized, iffeasible.

Mitigation Measure

The following mitigation measure is recommended to minimize impacts.

4.4-10 The Campus should place temporary construction fencing at least 5 feet from the trunk ofthe trees and construction equipment should not be parked under the tree canopies, iffeasible.

4.4-11 Demolition of the abandoned water tower at the existing WWTP could disturb roostingbats. This impact is considered less than significant.

No bats were observed in the abandoned water tank and no bat guano was observed. Becauseno bats would be impacted by removal of the tank, this potential impact is considered less than significant.

Mitigation Measure


4.4-12 Demolition of the existing sludge drying ponds would result in the potential loss of pondwildlife habitat. This impact is considered less than significant.

Four existing sludge drying ponds associated with the existing WWTP would be removed. Thesedrying ponds have minimal habitat value for wildlife, and their removal would have minimal impacts onwildlife; therefore, this impact is considered less than significant.

Mitigation Measure



Fish Resources

4.4-13 The proposed project would result in an increase in the amount of water discharged to theSouth Fork of Putah Creek that would result in an increase in fish habitat. This impact isconsidered beneficial.

The contribution of flows to the South Fork of Putah Creek from Campus WWTP dischargeswould increase with the proposed project. The annual average discharge from the existing Campus WWTPin 1996 was 1.7 million gallons per day (mgd), which contributes 2.6 cubic feet per second (cfs) of flowto the South Fork of Putah Creek below the existing outfall. The proposed WWTP would have an averageannual discharge of 2.5 mgd in 2005, which would contribute about 3.9 cfs of flow to the South Fork ofPutah Creek.

Mitigation Measure


4.4-14 Continued discharge of treated WWTP effluent to the South Fork of Putah Creek couldresult in acute and chronic exposure of fish to elevated levels of toxic pollutants. Thisimpact is considered potentially significant.

Based on the water quality analysis (see Chapter 4.1, “Hydrology and Water Quality”, andAppendix D), there is potential for the proposed discharge to expose fish to concentrations of contaminantsabove water quality standards, which could result in lethal or sublethal effects. Pollutants of concernidentified in the water quality analysis are copper, lead, and tributyltin. The primary source of thesepollutants is the WWTP effluent. Based on water quality modeling (see Chapter 4.1, “Hydrology andWater Quality”), this potential is greatest during dry periods, when there is little or no flow in the South Forkof Putah Creek, and little or no dilution of the effluent occurs.

Mitigation Measure


4.4-14 Implement Mitigation Measure 4.1-6 identified in Chapter 4.1.

Mitigation to minimize the potential of the effluent to cause acute and/or chronic toxicity to fish isthe same as discussed in Chapter 4.1, “Hydrology and Water Quality”.



4.4-15 The proposed WWTP (20 acres), in conjunction with 1994 LRDP development (200 acres),would increase the conversion of agricultural land and ruderal/annual grassland toCampus-related development to 220 acres and could result in the loss of special-statusplant species. This impact is considered significant.

The 1994 LRDP EIR identified the conversion of approximately 200 acres of agricultural land andruderal/annual grassland to Campus-related development as a significant impact because of the relatedimpacts on special-status plant species. The following mitigation measures were identified to reduce theseimpacts to a less-than-significant level.

4.7-1(a) During the project planning phase, the Campus shall conduct a rareplant survey if the site was previously undeveloped. Surveys shall beconducted by qualified biologists in accordance with the most currentDFG/USFWS guidelines or protocols and shall be conducted at the timeof year when the plants in question are identifiable. (Identificationperiods are included in Table 4.7-1, however, survey timing for thevarious plant species depends in part on yearly rainfall patterns and isdetermined on a case-by-case basis).

4.7-1(b) Based on the results of the survey, prior to design approval, theCampus in consultation with DFG and/or USFWS, shall determinewhether the project would result in a significant impact to any special-status plant species. Evaluation of project impacts shall consider thefollowing:

n The status of the species in question (e.g., officially listed bythe State or Federal Endangered Species Acts, candidate species,CNPS list).

n The relative density and distribution of the onsite occurrenceversus typical occurrences of the species in question.

n The habitat quality of the on-site occurrence relative tohistoric, current, or potential distribution of the population.

If these surveys reveal no occurrences of any species, or if theCampus in consultation with DFG or USFWS determines that nosignificant impacts on any special-status plant species would resultfrom project implementation, then no further mitigation would berequired.


Should one or more of special-status plant species occur on theproject site, and a determination of significant impact be made, thefollowing mitigation measure shall be required.

4.7-1(c) Prior to design approval, the Campus, in consultation with the DFGand/or the USFWS, shall prepare and implement a mitigation plan, inaccordance with any applicable State and/or Federal statutes or laws,that reduces impacts to a less-than-significant level.

Survey results indicate that the proposed WWTP project would not result in the loss of special-status plant species; however, it would contribute to the conversion of agricultural land and ruderal/annualgrassland.

Mitigation Measure


4.4-16 The proposed WWTP (20 acres), in conjunction with 1994 LRDP development (200 acres),would increase the conversion of agricultural land and ruderal/annual grassland habitatto Campus-related development and would result in the loss of 220 acres of generalwildlife habitat for resident and migratory species. This impact is considered less thansignificant.

Many species use agricultural land and ruderal/annual grassland for food and cover. This includesthe nomadic tricolored blackbird, wide-ranging winter migrating bird species, and resident birds and raptorsthat may occasionally forage on Campus lands. The 220 acres of agricultural land and ruderal/annualgrassland that would be converted represents approximately 5.5% of the total available agricultural land andruderal/annual grassland identified in the 1994 LRDP EIR. This loss relative to the abundance of remainingagricultural land and ruderal/annual grassland wildlife habitat would not result in a substantial adverse changein abundance of these species.

Mitigation Measure


4.4-17 The proposed WWTP (20 acres), in conjunction with 1994 LRDP development (200 acres),would increase the conversion of agricultural land and ruderal/annual grassland habitatto Campus-related development to 220 acres and could result in the loss of burrowing owlnesting habitat. This impact is considered potentially significant.

The known nesting areas for burrowing owls include the Raptor Center’s artificial burrowing owlnest mound near the southern end of the South Campus storm drain canal (occupied) and the area near the


Medical Sciences Complex and north of the Rec Pool Lodge (currently not occupied). Under the 1994LRDP, the lands north of the Rec Pool Lodge and a portion of those north of the Medical SciencesComplex would be preserved as open space to prohibit development of these areas as long as they areconsidered viable burrowing owl habitat. UC Davis has been monitoring the Central Campus nine timesper year since 1992 for the presence of burrowing owls. Only one burrowing owl has been observed inthe Central Campus area since 1992. As burrowing owls disperse, they may become established incurrently unoccupied areas. Therefore, potential impacts on nesting burrowing owls could result if theybecome established on project sites.

The 1994 LRDP EIR identifies the following mitigation measures to reduce the impact to a less-than-significant level.

4.7-3(a) The Campus shall continue to monitor the area around the MedicalSciences Complex for the presence or absence of burrowing owls.

4.7-3(b) The Campus, in consultation with the DFG, shall conduct a pre-construction breeding-season survey (approximately February 1 throughAugust 31) of proposed project sites during the same calendar year thatconstruction is planned to begin. The survey shall be conducted by aqualified biologist to determine if any burrowing owls are nesting on ordirectly adjacent to any proposed project site.

If phased construction procedures are planned for the proposedproject, the results of the above survey shall be valid only for theseason when it is conducted.

4.7-3(c) During the construction stage, the Campus in consultation with theDFG, shall avoid all burrowing owl nest sites potentially disturbed byproject construction during the breeding season while the nest is occupiedwith adults and/or young. The occupied nest site shall be monitored bya qualified biologist to determine when the nest is no longer used. Avoidance shall include the establishment of a 300-foot to 500-footdiameter non-disturbance buffer zone around the nest site. Disturbanceof any nest sites shall only occur outside of the breeding season and whenthe nests are unoccupied based on monitoring by a DFG approvedbiologist. The buffer zone shall be delineated by highly visible temporaryconstruction fencing.

Based on approval by DFG, pre-construction and pre-breedingseason exclusion measures may be implemented to precludeburrowing owl occupation of the project site prior to project-relateddisturbance.


Mitigation Measure


4.4-18 The proposed WWTP (20 acres), in conjunction with 1994 LRDP development (200 acres),would increase the conversion of agricultural land and ruderal/annual grassland habitatto Campus-related development to 220 acres, which could result in the loss of nestinghabitat for raptors (birds of prey). This impact is considered potentially significant.

As described in the setting section, many species of resident and migratory raptors besidesburrowing owls have been observed on the Campus during the breeding season and use the onsite habitatsfor nesting. Removal of ruderal/annual grassland vegetation in vacant fields or unmaintained field edgescould result in the loss of a nest site for the ground-nesting northern harrier. Tree removal or tree pruningcould result in the loss of active nest sites for the Swainson’s hawk or more common species, such as theblack-shouldered kite, red-tailed hawk, red-shouldered hawk, or American kestrel. Direct take of anactive raptor nest site would be in violation of Section 3503.5 of the Fish and Game Code, or if theSwainson’s hawk were involved, a violation of the California ESA.

The 1994 LRDP EIR identifies the following mitigation measures to reduce this impact to a less-than-significant level.

4.7-4(a) The Campus shall conduct a pre-construction or pre-tree pruning orremoval survey of trees greater than 30-feet tall (proposed activity)during the raptor breeding-season (approximately March 1 throughAugust 31). The survey shall be conducted by a qualified biologist duringthe same calendar year that the proposed activity is planned to begin todetermine if any nesting birds-of-prey would be affected.

If phased construction procedures are planned for the proposedactivity, the results of the above survey shall be valid only for theseason when it is conducted.

4.7-4(b) The Campus shall continue to conduct annual surveys to determinethe location of nesting Swainson’s hawks on the Campus. If nestingSwainson’s hawks are found during the survey at a previously unknownlocation within one-half mile of a project site and not within 100 yardsof a previously documented site, the Campus shall, prior to projectconstruction, contact the California Department of Fish and Game todetermine the potential for disturbance to nesting Swainson’s hawks andwill implement feasible changes in the construction schedule or otherappropriate adjustments to the project in response to the specificcircumstances.



Mitigation Measure


4.4-19 The proposed WWTP (20 acres), in conjunction with 1994 LRDP development (200 acres),would increase the conversion of agricultural land and ruderal/annual grassland habitatto Campus-related development to 220 acres and would result in the loss of foraginghabitat for the Swainson’s hawk. This impact is considered significant.

The 1994 LRDP EIR discusses the fact that up to 22 active Swainson’s hawk nests have beenrecorded within one-half mile of the Campus. The setting section of this EIR discusses the location ofSwainson’s hawk nests in the project vicinity. Given the abundance of foraging habitat that will remain onthe Campus and in the region, it is unlikely that the loss of 220 acres alone would directly affect any of thebreeding pairs located on or near the Campus. However, DFG has determined that the loss of suitableforaging habitat within a 10-mile radius of recorded nest sites constitutes take of the species pursuant to theCalifornia ESA. The loss of foraging habitat for the Swainson’s hawk is considered a significant impactbecause it is in conflict with state resource protection laws and guidelines.

The 1994 LRDP EIR identifies the following mitigation measure to reduce this impact to a less-than-significant level.

4.7-5 As Agricultural Land and Ruderal/Annual Grassland is converted toCampus development under the 1994 LRDP, the Campus willcompensate for the loss of Swainson’s hawk foraging habitat at a 1:1ratio of acres lost to acres preserved through the implementation of oneor a combination of the following methods.

n Approximately 40 acres of Cropland habitat in the "C" tractadjacent to the Putah Creek Reserve on the West Campus willremain Campus agricultural research uses but will be under land userestrictions that will ensure cropland cover types that are suitable asSwainson’s hawk foraging habitat. No incompatible uses such asorchards, vineyard, or development will be allowed in the areas setaside for Swainson’s hawk foraging habitat. However, normal croprotations may periodically result in unsuitable cover types of annualcrops.


n Approximately 20 acres of land within the North Fork Cutoffthat currently support livestock enclosures will be restored to awoodland and grassland habitat.

n Approximately 55 acres of existing orchards adjacent toPutah Creek at the Russell Ranch will be removed, converted to acover type suitable for Swainson’s hawk foraging, and added to thePutah Creek Reserve.

n Approximately 85 acres at the Russell Ranch that have beendesignated as a habitat restoration and research area will includethe establishment of cover types that are suitable Swainson’s hawkforaging habitat.

Mitigation Measure


4.4-20 The proposed WWTP, in conjunction with 1994 LRDP development, could result in thepotential failure of Swainson’s hawk nesting efforts. This impact is considered potentiallysignificant.

The setting section discusses the location of Swainson’s hawk nests in the project vicinity. DFGhas established a one-half–mile radius around known Swainson’s hawk nests as a zone where potentialdisturbances could disrupt nesting efforts. Swainson’s hawks are tolerant of human activity in manyinstances; however, the operation of machinery and earth-moving equipment in proximity to an activeSwainson’s hawk nest could cause nest abandonment or other types of reproductive failure.

The 1994 LRDP EIR identifies the following mitigation measures to reduce this impact to a less-than-significant level.

4.7-6(a) The Campus shall conduct a pre-construction breeding season surveyof the proposed project site, and within a one-half-mile radius of the site,to determine the presence or absence of any nesting Swainson’s hawks.

If any Swainson’s hawks are nesting within a one-half-mile radius ofthe project site, the Campus shall, in consultation with DFG,determine the potential for disturbance to nesting Swainson’s hawksand will implement feasible changes in the construction schedule orother appropriate adjustments to the project in response to thespecific circumstances.


4.7-6(b) The Campus shall continue to conduct annual surveys to determinethe location of nesting Swainson’s hawks on and within ½ mile of theCampus. If nesting Swainson’s hawks are found during the survey at apreviously unknown location within one-half mile of a project site andnot within 100 yards of a previously documented site, the Universityshall, prior to project construction, contact the California Department ofFish and Game to determine the potential for disturbance to nestingSwainson’s hawks and will implement feasible changes in theconstruction schedule or other appropriate adjustments to the project inresponse to the specific circumstances.


Mitigation Measure


4.4-21 Development of the proposed WWTP, in conjunction with development allowed under the1994 LRDP, could result in the loss of potential habitat for the VELB. This impact isconsidered potentially significant.

A systematic survey of the proposed WWTP project site located elderberry shrubs that could beaffected by the project. Elderberry shrubs are the host plant species for the VELB, and USFWS considersall elderberry shrubs within the historical range of VELB to be potential habitat for this federally listedthreatened species. Elderberry shrubs are also known to occur in the valley-foothill riparian habitat alongPutah Creek, in the North Fork Cutoff in the Central Campus, and at two locations on the West Campus. Additionally, elderberry shrubs may become established elsewhere as seeds are dispersed by birds orother means. Therefore, potential habitat for the VELB may be established on project sites in the futurethat currently do not support any elderberry shrubs. Destruction of elderberry shrub stems greater than 1inch in diameter is considered a take under the federal ESA and requires mitigation pursuant to USFWSguidelines.


4.7-7 During the project design stage and as a condition of projectapproval, the Campus shall:

(a) Conduct a project-specific survey for all potential VELBhabitat, including a stem count and an assessment of historic orcurrent VELB use;


(b) Avoid and protect all potential VELB habitat within a naturalopen space area where feasible; and

(c) Where avoidance is infeasible, develop and implement a VELBmitigation plan in accordance with the most current USFWSmitigation guidelines for unavoidable take of VELB habitat pursuantto either Section 7 or Section 10(a) of the Federal EndangeredSpecies Act.

Mitigation Measure


4.4-22 Cumulative development in the region, in conjunction with the proposed WWTP (20 acres)and 1994 LRDP development, would add an additional 20 acres to the 1,227 acres ofagricultural land and ruderal/annual grassland habitat loss in the region for resident andmigratory wildlife species identified in the 1994 LRDP EIR. This impact is consideredsignificant and unavoidable.

The 1994 LRDP EIR identified the cumulative loss of agricultural land and ruderal/annual grasslandas a significant and unavoidable impact. This impact is primarily the result of growth in the City of Davisand other cities in Yolo and Solano Counties resulting in the conversion of agricultural land and annualhabitat to urban uses. The continued loss of these habitat types will also contribute to the regional loss offoraging habitat for the Swainson’s hawk and burrowing owl.

Yolo County and the Cities of Davis, West Sacramento, Winters, and Woodland are in the processof preparing a countywide habitat management plan with the goal of achieving no net loss of habitat valuesfor special-status species. UC Davis is participating in this effort in an advisory capacity. The preparationof a regional habitat management plan may ultimately resolve and mitigate the cumulative impacts on special-status species and other wildlife; however, at this time no such plan has been adopted. While the Campusproposal to compensate for lost habitat on a 1:1 basis will reduce project-specific impacts to a less-than-significant level, the conversion of habitat to urban uses throughout the region is considered a substantialreduction in the acreage of habitat for native wildlife and therefore remains a significant impact.

The 1994 LRDP EIR identified the following mitigation measures to reduce the magnitude of theimpact; however, the feasibility and/or implementation of Mitigation Measure 4.7-9(b) cannot be guaranteedby the University of California because it falls within other jurisdictions to enforce and monitor. For thisreason, the University must consider the impact significant and unavoidable.


4.7-9(a) Implement Mitigation Measures 4.7-1, 4.7-3, 4.7-4, 4.7-5, and 4.7-6.

4.7-9(b) The County of Yolo, when implementing the County-wide habitatmanagement plan, should impose a 1:1 mitigation ratio of habitatpreserved to that converted on all development projects within theirjurisdiction that convert agricultural land and annual grassland habitatto urban development.

Mitigation Measure


4.4-23 The proposed WWTP, in conjunction with 1994 LRDP development accommodated by theproposed project, would contribute to the loss of potential habitat for the VELB. Thisimpact is considered potentially significant.

The 1994 LRDP EIR discussed the presence of elderberry shrubs on the Campus in the valley-foothill riparian habitat along Putah Creek and at two locations on the West Campus. The USFWSconsiders all elderberry shrubs within the historic range of VELB as potential habitat for this federally listedspecies. This impact was considered potentially significant because destruction of elderberry stems greaterthan 1 inch in diameter is considered “take” under the federal ESA and requires mitigation pursuant toUSFWS guidelines.

The 1994 LRDP EIR identified the following mitigation measure to reduce this impact to a less-than-significant level.

4.7-7 During the project design stage and as a condition of project approval, theCampus shall:

(a) Conduct a project-specific survey for all potential VELB habitat,including a stem count and an assessment of historic or current VELBuse;

(b) Avoid and protect all potential VELB habitat within a natural openspace area where feasible; and

(c) Where avoidance is infeasible, develop and implement a VELBmitigation plan in accordance with the most current USFWS mitigationguidelines for unavoidable take of VELB habitat pursuant to eitherSection 7 or Section 10(a) of the Federal Endangered Species Act.

Mitigation Measure



4.4-24 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, could contribute to the cumulative loss of VELB habitat. This impactis considered significant and unavoidable.

The 1994 LRDP EIR identified the cumulative loss of VELB habitat as a significant andunavoidable impact. Because the VELB is federally listed as threatened, USFWS guidelines requiremitigation of losses of this species’ host plant, the Mexican elderberry shrub. However, while the Campusproject-specific mitigation will compensate for the Campus-related impacts, the University cannot guaranteeUSFWS’ ability to impose mitigation for loss of VELB habitat for other projects; this makes this cumulativeimpact significant and unavoidable.

The 1994 LRDP EIR identified the following mitigation measures to reduce the magnitude of theimpact; however, the feasibility and/or implementation of Mitigation Measure 4.7-9(b) cannot be guaranteedby the University of California because it falls within the jurisdiction of the USFWS to enforce and monitor. For this reason, the University must consider the impact significant and unavoidable.

4.7-10 Implement Mitigation Measures 4.7-7(a), (b), and (c).

Mitigation Measures



Chapter 4.5 Cultural Resources

INTRODUCTION

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), thisanalysis focuses on the potential for construction to damage or destroy archaeological resources, historicalstructures or landscape features, unique ethnic cultural values, or religious or sacred uses. Potential impactsrelated to paleontological resources were adequately addressed by the 1994 LRDP EIR.

The following information is based on the 1994 LRDP EIR and two letter reports prepared byPacific Legacy titled Archaeological Investigations for the Wastewater Treatment Plant on the UCDavis Campus, Yolo County, California (Pacific Legacy 1996a) and Supplemental Report forArchaeological Investigations of the Revised Wastewater Treatment Plant on the UC Davis Campus,Yolo County, California (Pacific Legacy 1996b). A third letter report prepared by Jones & StokesAssociates titled Historic Building Inventory and Evaluation of California Register of HistoricResources and National Register of Historic Places Eligibility for the UC Davis WastewaterTreatment Plant Replacement Project (Jones & Stokes Associates 1996) assesses historic resources.The full reports are hereby incorporated by reference; the reports are available for review during normaloperating hours at the UC Davis Planning and Budget Office, 376 Mrak Hall, UC Davis.


The proposed project includes decommissioning and potential partial or complete demolition of theexisting WWTP, decommissioning and demolition of the existing sludge drying ponds, and construction ofthe proposed WWTP as well as influent and effluent pipelines. Because some of the structures at theexisting WWTP were built in 1949, demolition of the existing WWTP could damage or destroy historicalstructures. The Revised Initial Study identified the need for an assessment of historic resources. Demolitionof the existing sludge drying ponds would not result in any impacts because the ponds are not historicalstructures and are not located in an area of known archaeological sensitivity.

Construction of the proposed WWTP would involve subsurface excavation for the treatment plantand pipeline construction. Because of the proximity of some elements of the proposed WWTP project to


the Arboretum Waterway (the historical Putah Creek drainage), which is known to be archaeologicallysensitive, the Revised Initial Study identified the need for an archaeological investigation. The investigationstrategy included a surface survey and subsurface augering for inspection of buried soil deposits.

Prehistoric Resources

The proposed WWTP site is currently used as pasture. The nearest drainage (a physical featurewith high probability of past cultural uses) is the Arboretum Waterway, which is the historical Putah Creekdrainage that lies approximately 0.6 mile north of the proposed WWTP site. Years ago the land was opengrassland with scattered oak groves. As discussed in the 1994 LRDP EIR, the Campus lies within theethnographic territory of the Patwin. Patwin territory included the southern portion of the Sacramento RiverValley from the Sacramento River westward to the lower foothills of the North Coast Range east of ClearLake, and extending north to the present town of Princeton and southward to San Pablo and Suisun Bays. Like that of most northern California groups, Patwin subsistence was based on seasonal migrations ofhunting and gathering throughout their territory. The largest ethnographic villages at the time of historicalcontact (i.e., A.D. 1800) were situated along major drainages such as Putah Creek, Cache Creek, and theSacramento River.

As stated in the 1994 LRDP EIR, prior archaeological investigations have ascertained that thearchaeological sensitivity of locations in the region depends on the particular microenvironment. The mostsensitive areas are located along the banks of the tributaries and old slough channels of Putah Creek. Although archaeological sites are usually discovered by surface examination, many buried prehistoric siteshave been documented in the Sacramento Valley and Delta region, exacerbating the difficulty of identifyingsite locations. A case example is that of “Capay Man”, in which skeletal remains were discovered erodingfrom a stream bank (e.g., 6 feet beneath the surface) near Capay in Yolo County. Similarly, constructionactivities for a recent housing development in Dixon encountered human burials and archaeological depositsat depths of nearly 8 feet. Deep burial does not necessarily reflect great antiquity but may indicate rapiddeposition resulting from seasonal flooding and alluviation.

Native American Coordination

Pacific Legacy regularly consults with Mary Norton on proposed development projects in the Davisarea. Ms. Norton is recognized as the most likely descendant of local prehistoric people by the NativeAmerican Heritage Commission (NAHC). She is familiar with native Patwin sites throughout Yolo County,including those on the UC Davis campus. Ms. Norton is informed of impending projects that have apotential to disturb archaeological deposits and her concerns are solicited. Ms. Norton has respondedaffirmatively regarding the need for archaeological investigations prior to construction activities near theArboretum Waterway for the proposed WWTP.


Background Research

Prior to fieldwork, results of a records search conducted at the Northwest Information Center ofthe California Historical Resources Information System at California State University, Sonoma, wereexamined for data on previous archaeological surveys and site findings in the vicinity of the proposed projectsite. This information was supplemented by more recent investigations (e.g., 1994-1995) conducted byBioSystems Analysis and Pacific Legacy. The records search and background study revealed that sixarchaeological investigations have been conducted on lands in the proposed project area. All of thesesurveys involved pedestrian surface surveys in which no archaeological sites or isolated finds were found.

The records search and background research revealed that no archaeological sites are recordedin the project area, although seven sites are reported to exist within a 1-mile radius of the project site.

Field Methods and Results

A surface survey of the proposed project was conducted on June 25 and 26 and July 1, 1996. After the surface survey was completed, 12 locations were selected for subsurface testing using amechanical auger. Subsurface augering was conducted at the treatment plant site and along the influent andeffluent pipeline routes between the existing treatment plant and the South Fork of Putah Creek.

The surface survey involved an archaeologist walking systematic transects across the proposedWWTP site and along the influent and effluent pipelines, looking for physical evidence of prehistoric landuse. Particular attention was paid to areas within the vicinity of the historic Putah Creek channel(Arboretum Waterway), which is considered to be the most likely location for buried archaeologicaldeposits and features. No archaeological material was identified during the surface survey.

The 12 auger borings were excavated to 5-10 feet from the ground surface using a spiral truck-mounted, 24-inch-diameter auger. Dry samples of excavated soils from various depth increments werescreened through ¼-inch wire mesh to determine whether cultural artifacts such as flaked stone, bone, andshell were present. No archaeological deposits or artifacts were identified from the auger tests.

Historic Resources

The component of the proposed WWTP project that necessitates the current inventory andevaluation is the decommission and potential partial or complete demolition of the existing WWTP, whichis located in the Central Campus area south and west of the intersection of La Rue and Bioletti Way. Thecentral facilities of the existing WWTP, consisting of 10 buildings and structures, are 46 years old. An off-site portion of the existing WWTP, consisting of four earthen-bermed sludge drying ponds, is located westof County Road 98. Because these ponds are constructed of simple earthen berms and are only 36 yearsold, they do not necessitate an inventory or evaluation.


Historic Research

Historic research was conducted at the California State Library in Sacramento, the UC DavisPlanning and Budget Office, and at the UC Davis Office of Facilities and Engineering Services. TheCalifornia State Library provided histories of the Davis area as well as that of the University itself. Theoffices at the UC Davis Campus provided valuable information regarding the exact date of design andconstruction of the WWTP structures.

Historic Setting

Jerome C. Davis was a prominent Central Valley farmer who settled in the location that now bearshis name. Davis raised cattle, horses, and sheep, and grew wheat, peaches and grapes. By 1864, Davis’ranch totaled approximately 13,000 acres, more than 8,000 of which were fenced. Large-scale cultivationhad already begun in the Davis area as early as the 1850s. (University of California, Davis 1994.)

By 1868 an east/west line of the California Pacific Railroad entered Yolo County near the stockfarm of Jerome and Isaac Davis. Promoters of the railroad purchased land from the Davis family and laidout a town that they named Davisville, which turned out to be an important stop along the rail route. By theturn of the century, Davisville had become the commercial center for the surrounding agricultural area. In1906, the name of the Davisville post office was shortened to the present name, Davis. (University ofCalifornia, Davis 1994.)

In the early 20th century, hundreds of miles of levees were constructed in the Sacramento Valleyas part of a massive flood control project. This controlling of flood waters allowed for the reclamation oflands near the Sacramento River, priming literally thousands of previous swamp acres for cultivation. Centuries of recurring floods, however, left deep deposits of rich soil that were recognized for theiragricultural potential. By the 1860s, 700 people lived on farms in the Putah Township near Putah Creek,which runs through the UC Davis campus. (University of California, Davis 1994.)

Initiated by agricultural leaders in the state in the 1880s, the state legislature established theUniversity Farm in 1905, and in 1906 plans were underway to transform a 779-acre tract of land into theUniversity. Faculty members at the College of Agriculture at Berkeley worked with University architectsto develop a site plan and locations for the first four buildings. These structures included acreamery/administration building, a livestock judging pavilion/campus auditorium, and two residences. These structures, the Silo, Wyatt Pavilion Theater, North Hall, and South Hall, were generally wood-framed, shingle-sided buildings. (Larkey 1984.)

In January 1909, the first regular Farm School classes were attended by 28 students who weretaught by 16 faculty members who commuted from UC Berkeley. In the 1910s, student dormitories,additional teaching and research facilities, and improved irrigation systems were constructed. In 1922, a


four-year degree program was offered at the University Farm, which had become a branch of the Collegeof Agriculture of UC Berkeley. The offering of a four-year degree ushered in a new era of growth anddevelopment at the University Farm, and by 1930 the campus had grown to encompass 1,000 acres. (Larkey 1984.)

Immediately following World War II, a major period of growth occurred at the University Farm. Campus administration was reorganized, and the curriculum was expanded to include a School ofVeterinary Medicine. In 1951, the College of Letters and Science was organized, and in 1959 Davis wasauthorized as a general campus of the University of California. In 1961, a graduate division was establishedwith professional schools of engineering, law, medicine, and administration. (Larkey 1984, Kyle 1990.)

Field Methods and Results

Two members of Jones & Stokes Associates’ cultural resources team conducted an inventory ofhistoric buildings and structures at the WWTP at UC Davis on August 14, 1996. Each building andstructure at least 45 years old was examined, photographed, measured, and recorded on CaliforniaDepartment of Parks and Recreation Primary Record forms and Building, Structure, and Object Recordforms. These forms are located in Appendix A of the Historic Building Inventory and Evaluation report. Original copies of the forms have been placed on file at the Northwest Information Center, CaliforniaHistorical Resources File System, California State University, Sonoma, in Rohnert Park, California.

The buildings and structures over 45 years old at the WWTP consist of one office building, onerefuse building, one effluent pumphouse, two settling tanks, two trickling filters, two anaerobic digesters,and one abandoned water storage tank. All of these buildings and structures were designed in 1949 by theEngineering Office of Clyde C. Kennedy in San Francisco. They were constructed in 1950 and beganoperation in 1951.

Effluent Pumphouse. The effluent pumphouse has a rectangular plan and is constructed of board-formed reinforced concrete with a textured surface and a flat, built-up roof. One and one-half stories ofthe two and one-half story building are located below the ground surface. This deep basement story isaccessed by interior and exterior stairwells. The building interior features an electrical switch station anda central stairwell equipped with a hoist for transporting pumping equipment to and from the basement story. Other pumphouse features include a partial glass block facade on the north side, metal casement windows,utility doors, safety lights, and metal vents.

Office Building. The administration or office building has a roughly square plan and is constructedof board-formed reinforced concrete with a flat, built-up roof. The north facade is equipped with originalmetal casement windows; however, the east and south side windows have been replaced with aluminumsliders. Two loading bays were originally located on the south side of the building, but only one bay remainsin operation while the other has been filled in with a concrete block partition wall equipped with a window. This office building appears to have been upgraded and remodeled in the 1970s or 1980s.


Settling Tanks. Each of the three settling, or sedimentation, tanks are constructed primarily belowthe surface of the ground in board-formed reinforced concrete. They are rectangular in plan and containseven wells separated by concrete partitions. Each settling tank is surrounded by metal pipe railing.

Trickling Filters. Each of the two trickling filters consists of a circular, board-formed concretetank approximately 22 feet in diameter and 6 feet in height. An 18-inch-high concrete curb around the baseof each tank borders a 3-foot-wide moat for circulating and draining treated water from the filter. The filterwalls have been reinforced with metal banding, a later modification that significantly alters their originalsmooth-surfaced appearance. The filters contain layers of river rock over which waste water is distributedfrom a central rotating sprinkler. Stairs and metal pipe railings provide maintenance access to the tops ofthe tanks.

Abandoned Storage Tank. A large circular tank reservoir located at the north end of the WWTPis approximately 110 feet in diameter and 20 feet in height. It is constructed of board-formed concretepoured in segmented levels and is equipped with a flat wooded roof clad in corrugated metal. The roof isflush with the sides but elevated to provide a clerestory for ventilation.

Refuse Building. This two-story building is rectangular in plan and constructed of board-formedreinforced concrete with a flat, built-up roof. Covered loading docks and bays are located on the north sideof the building at the upper level and at the lower level on the east side. The upper level loading dock isreached by a ramp driveway. Glass block panels are located in the eastern and southern facades to lightthe interior of the building. This structure originally housed a three-stage incinerator and a garbage grinderused to process solid waste. It also housed a belt press for sludge dewatering prior to transport to sludgedrying ponds.

Anaerobic Digesters. Each of these two circular holding tanks is approximately 40 feet indiameter with a 22-foot side-wall depth and is constructed of board-formed concrete with concrete caps.

REGULATORY SETTING

The 1994 LRDP EIR discusses the regulatory context for the treatment of cultural resources. Insummary, there are specific criteria for determining whether prehistoric and historic sites or objects aresignificant and/or protected by law. The Campus is subject to federal and state regulations as identified inthe 1994 LRDP EIR.





n result in the damage or destruction of prehistoric sites or artifacts that would meet CEQAcriteria for significance (see Appendix K of the CEQA Guidelines) and/or federal criteria forsignificance, or

n result in the damage or destruction of historical structures, features, artifacts, landscaping, orsites that would meet CEQA, federal, or Campus criteria for significance.


Prehistoric Resources

4.5-1 Excavation, grading, and construction activities could damage or destroy buried culturalresources. This impact is considered potentially significant.


4.10-1(a) Prior to project approval, the Campus shall determine the level ofarchaeological investigation that is appropriate for the project site. Thelevels are:

Minimum: in areas of known archaeological sensitivity (i.e.,known sites), excavation less than 18" deep and in arelatively small area (e.g., routine maintenance andoperations such repairing broken facilities, a short trench forlawn irrigation, tree planting, etc.); in other areas, excavationless than 36" deep and in a relatively small area.

Moderate: excavation below 36" and/or over a large area on anysite that has not been characterized and is not suspected to bea likely location for archaeological resources.

Intensive: excavation below 18" and/or over a large area on anysite that is within 800' of the historic alignment of Putah


Creek (prior to 1880) or that is adjacent to a recordedarchaeological site.

4.10-1(b) For sites requiring minimum investigation, the following steps will betaken.

(i) Prior to disturbing the soil, contractors shall be notified thatthey are required to watch for potential archaeological sites andartifacts and to notify the Campus if anything is found. In addition,Campus employees whose work involves routinely disturbing the soilshall be trained to recognize evidence of potential archaeologicalsites and artifacts.

(ii) If resources are discovered during activities, all soil disturbingwork within 100 feet of the find shall cease. The resources shall beevaluated by a qualified archaeologist who will determine andadvise the Campus on the potential for the activity to affect asignificant archaeological resource.

(iii) If the activity might affect a significant archaeologicalresource, consistent with CEQA and Appendix K of the CEQAGuidelines addressing archaeological impacts, a plan for surveyingthe remainder of the site and conducting appropriate data recoveryand other mitigation shall be prepared and implemented using theservices of a qualified archaeologist.

(iv) If human remains are found, the County coroner shall becontacted. The coroner shall contact the Native American HeritageCommission, which shall notify the appropriate descendant. TheCampus shall coordinate re-interment of Native American remainswith the NAHC and the designated descendant.

4.10-1(d) For sites requiring intensive investigation, the following steps shallbe taken.

(i) A subsurface investigation shall be conducted by a qualifiedarchaeologist, prior to project approval. The archaeologist shalldetermine and advise the Campus on the potential for the project toaffect a significant archaeological resource. If the project mightaffect a significant archaeological resource, the Campus shall adoptan appropriate mitigation plan at the time of project approval. Iffeasible, the Campus shall consider avoidance at significant


archaeological sites as the preferred mitigation. At a minimum, datarecovery at significant archaeological sites will be implemented.

(ii) A qualified archaeologist shall be present during grading andexcavation, as deemed appropriate.

(iii) Steps (i) through (iv) of Mitigation Measure 4.10-1(b) shall beimplemented.

In accordance with 1994 LRDP EIR Mitigation Measure 4.10-1(a), the proposed WWTP projectwas identified as a project requiring intensive archaeological investigation prior to project approval becauseof the project’s proximity to the historical stream channel of Putah Creek.

In compliance with 1994 LRDP EIR Mitigation Measure 4.10-1(d)(i), potential prehistoric culturalresource impacts of the project have been evaluated. No cultural resources have been found at the projectsite and no additional studies have been recommended. Implementing other 1994 LRDP EIR mitigationmeasures, specifically 4.10-1(b)(i through iv) and 4.10-1(d)(ii), as part of the project would ensure that theproject would result in a less-than-significant cultural resources impact.

Mitigation Measure


Historic Resources

4.5-2 Demolition of the existing WWTP could damage or destroy historical structures. Thisimpact is considered less than significant.


4.10-2(a) Prior to altering a structure at least 45 years of age, the Campus shalldevelop a process for identifying its relative historic value. In additionto CEQA and other state guidelines, the process shall consider the roleof structures in the history of the University system, the Campus, and theregion.

4.10-2(b) If any existing structure on a proposed construction site is over 45years of age:

(i) The Campus shall use the process developed under MitigationMeasure 4.10-2(a) to determine whether the structure is historicallysignificant;


(ii) If historically significant, the building shall be preserved andreused when feasible; and

(iii) If historically significant, and preservation and reuse cannotoccur on site, the historical building shall be moved to an area setaside by the Campus for historic buildings of the same era whenphysically and financially feasible.

(iv) If a historically significant structure is to undergo majorrenovation, or be moved and/or destroyed, the Campus shallproduce a record of the building similar to National Parks Scenicstandards (Historical American Building Surveys). A copy of therecord shall be deposited with the University Archives, ShieldsLibrary Special Collections.

Adequate recordation would include, at a minimum, the following:

n the development of site-specific history and appropriatecontextual information regarding the particular resource; inaddition to archival research and comparative studies, this taskcould involve limited oral history collection;

n accurate mapping of the noted resources, scaled to indicatesize and proportion of the structures;

n architectural descriptions of affected structures;

n photodocumentation of the designated resources, both in stilland video formats; and

n recordation of measured architectural drawings, in the caseof specifically designated buildings of higher architectural merit.

4.10-2(c) Prior to major renovation, moving, or destroying a historicallysignificant structure, the Campus shall insure that historically significantartifacts within the building and the surrounding area shall be recordedand deposited with the appropriate museum.

In accordance with the 1994 LRDP EIR Mitigation Measure 4.10-2, the buildings and structuresat least 45 years of age at the existing WWTP were identified as requiring evaluation as to their historicsignificance because the buildings and structures will be destroyed as a part of the proposed project. Historic significance equates to eligibility for listing on the California Register of Historical Resources(CRHR) or the National Register of Historic Places (NRHP).


In compliance with the 1994 LRDP EIR, with CEQA, and with Section 106 of the NationalHistoric Preservation Act (NHPA), the historic buildings and structures at the existing WWTP wereevaluated as to their eligibility for listing on the CRHR or the NRHP. As a result of this evaluation, nobuildings or structures appear to be eligible for either the CRHR or the NRHP. No additional studies havebeen recommended.

Mitigation Measure



4.5-3 The proposed WWTP, in conjunction with 1994 LRDP development, could damage ordestroy buried cultural (prehistoric or historic) resources. This impact is consideredsignificant and unavoidable.

As stated in the 1994 LRDP EIR, development allowed under the 1994 LRDP could affectarchaeological and historical resources. Any time earth is disturbed, buried resources can be damaged ordestroyed. This risk is highest along the existing banks of the tributaries and slough channels of Putah Creekand the North Fork Cutoff/Arboretum Waterway (the historical channel of Putah Creek).

The 1994 LRDP EIR identified the following mitigation measures to reduce the magnitude of theimpact, but the damage or destruction of buried cultural (prehistoric or historic) resources would remainsignificant and unavoidable.

4.10-1(a) Prior to project approval, the Campus shall determine the level ofarchaeological investigation that is appropriate for the project site. Thelevels are:

Minimum: in areas of known archaeological sensitivity (i.e.,known sites), excavation less than 18" deep and in arelatively small area (e.g., routine maintenance andoperations such repairing broken facilities, a short trench forlawn irrigation, tree planting, etc.); in other areas, excavationless than 36" deep and in a relatively small area.

Moderate: excavation below 36" and/or over a large area on anysite that has not been characterized and is not suspected to bea likely location for archaeological resources.


Intensive: excavation below 18" and/or over a large area on anysite that is within 800' of the historic alignment of PutahCreek (prior to 1880) or that is adjacent to a recordedarchaeological site.

4.10-1(b) For sites requiring minimum investigation, the following steps will betaken.

(i) Prior to disturbing the soil, contractors shall be notified thatthey are required to watch for potential archaeological sites andartifacts and to notify the Campus if anything is found. In addition,Campus employees whose work involves routinely disturbing the soilshall be trained to recognize evidence of potential archaeologicalsites and artifacts.

(ii) If resources are discovered during activities, all soil disturbingwork within 100' of the find shall cease. The resources shall beevaluated by a qualified archaeologist who will determine andadvise the Campus on the potential for the activity to affect asignificant archaeological resource.

(iii) If the activity might affect a significant archaeologicalresource, consistent with CEQA and Appendix K of the CEQAGuidelines addressing archaeological impacts a plan for surveyingthe remainder of the site and conducting appropriate data recoveryand other mitigations shall be prepared and implemented using theservices of a qualified archaeologist.

(iv) If human remains are found, the County coroner shall becontacted. The coroner shall contact the Native American HeritageCommission, which shall notify the appropriate descendant. TheCampus shall coordinate re-interment of Native American remainswith the NAHC and the designated descendant.

4.10-1(c) For sites requiring moderate level of investigation, the following stepsshall be taken.

(i) A surface survey shall be conducted by a qualifiedarchaeologist prior to project approval.

(ii) If evidence of archeological resources are found, a qualifiedarchaeologist shall prepare and implement a plan for subsurfaceinvestigation of the site. The archaeologist shall determine and


advise the Campus on the potential for the project to affect asignificant archaeological resource. If the project might affect asignificant archaeological resource, the Campus shall adopt anappropriate mitigation plan at the time of project approval. Iffeasible, the Campus shall consider avoidance at significantarchaeological sites as the preferred mitigation. At a minimum, datarecovery at significant archaeological sites will be implemented.

(iii) If evidence of archaeological resources is not found during thesurface survey, a qualified archaeologist shall be present duringexcavation and grading, as deemed necessary by the archaeologist.

(iv) Steps (i) through (iv) of item (b) shall be implemented.

4.10-1(d) For sites requiring intensive investigation, the following steps shallbe taken.

(i) A subsurface investigation shall be conducted by a qualifiedarchaeologist, prior to project approval. The archaeologist shalldetermine and advise the Campus on the potential for the project toaffect a significant archaeological resource. If the project mightaffect a significant archaeological resource, the Campus shall adoptan appropriate mitigation plan at the time of project approval. Iffeasible, the Campus shall consider avoidance at significantarchaeological sites as the preferred mitigation. At a minimum, datarecovery at significant archaeological sites will be implemented.

(ii) A qualified archaeologist shall be present during grading andexcavation, as deemed appropriate.

(iii) Steps (i) through (iv) of item (b) shall be implemented.

Mitigation Measure


4.5-4 The proposed WWTP, in conjunction with 1994 LRDP development, could damage ordestroy historical structures during construction and/or renovation activities. This impactis considered significant.

As stated in the 1994 LRDP EIR, development allowed under the 1994 LRDP could result in thedemolition or relocation of existing historical structures. Over 50 structures on the Campus are over 45years old and most of the older buildings on the campus have not been evaluated for historical significance.


The 1994 LRDP EIR identified the following mitigation measures to reduce this impact to a less-than significant level.

4.10-2(a) Prior to altering a structure at least 45 years of age, the Campus shalldevelop a process for identifying its relative historic value. In additionto CEQA and other State guidelines, the process shall consider the roleof structures in the history of the University system, the Campus and theregion.

4.10-2(b) If any existing structure on a proposed construction site is over 45years of age:

(i) the Campus shall use the process developed under MitigationMeasure 4.10-2(a) to determine whether the structure is historicallysignificant;

(ii) if historically significant, the building shall be preserved andreused when feasible; and

(iii) if historically significant, and preservation and reuse cannotoccur on site, the historical building shall be moved to an area setaside by the Campus for historic buildings of the same era whenphysically and financially feasible.

(iv) If a historically significant structure is to undergo majorrenovation, or be moved and/or destroyed the Campus shall producea record of the building similar to National Parks Scenic standards(Historical American Building Surveys). A copy of the record shallbe deposited with the University Archives, Shields Library SpecialCollections.

Adequate recordation would include, at a minimum,the following:

n the development of site-specific history andappropriate contextual information regarding the particularresource; in addition to archival research and comparativestudies, this task could involve limited oral history collection;

n accurate mapping of the noted resources, scaled toindicate size and proportion of the structures;


n architectural descriptions of affected structures;

n photodocumentation of the designated resources, bothin still and video formats; and

n recordation of measured architecturaldrawings, in the case of specifically designated buildingsof higher architectural merit.

4.10-2(c) Prior to major renovation, moving or destroying a historicallysignificant structure, the Campus shall insure that historically significantartifacts within the building and the surrounding area shall be recordedand deposited with the appropriate museum.

Mitigation Measure


4.5-5 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, would contribute to a cumulative loss of cultural (prehistoric andhistoric) resources in Yolo and Solano counties. This impact is considered significant andunavoidable.

The 1994 LRDP EIR discusses and evaluates cumulative cultural resources impacts and mitigationmeasures. The analysis in that report concluded that the loss of cultural resources as a result ofimplementation of the 1994 LRDP could contribute to a regionwide impact that cannot be fully remedied.

The 1994 LRDP EIR identified the following mitigation measures to reduce the magnitude of theidentified impacts; however, the feasibility and/or implementation of Mitigation Measure 4.10-4(b) cannotbe guaranteed by the University of California because it falls within other jurisdictions to enforce andmonitor. For these reasons, the University must consider the impact significant and unavoidable.

4.10-4(a) Implement Mitigation Measures 4.10-1(a) through 4.10-1(d), 4.10-2(a)through (c), and 4.10-3(a) through (c).

4.10-4(b) The Yolo and Solano County general plans and the City of Davisgeneral plan contain policies which address the preservation of culturalresources. It is within the jurisdiction of these agencies to implement thegeneral plan policies which encourage the protection and restoration ofcultural resources.


The general plans contain policies that encourage the protection and restoration of culturalresources. These policies do not prohibit the destruction of all significant cultural resources, so they wouldonly partially offset impacts on archaeological and historic resources.

Mitigation Measure



Chapter 4.6 Land Use and Planning

INTRODUCTION

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), thisanalysis focuses on the potential for conflicts with designated adjacent land uses and the potential loss ofprime farmland. Potential impacts related to land use plans and policies adopted by adjacent jurisdictions,loss of agricultural production, and the physical arrangement of established communities were adequatelyaddressed by the 1994 LRDP EIR.


Land Use Context

Existing WWTP Site

The existing WWTP is located in the Central Campus area south and west of the intersection of LaRue Road and Bioletti Way. The existing WWTP site is bordered by La Rue Road to the north, and itssouthern boundary runs along Putah Creek Lodge Road on the banks of the Arboretum Waterway. A 6-foot-high chain link fence surrounds the WWTP site. The site is primarily developed with WWTPequipment, buildings, parking, and mature landscaping.

The 1994 LRDP establishes land use designations on the Campus. The existing WWTP site andthe area just west of the site containing the mail room, the Fleet Services garage, and the Unitrans garageare designated as Support. The Arboretum Waterway to the south of the site is designated as Open SpaceTeaching/Research. The area north of La Rue Road is designated as Parking.

Existing Sludge Drying Ponds


The four existing sludge drying ponds are west of County Road 98, south of the main CaliforniaRegional Primate Research Center (CRPRC) buildings and immediately south of the former CRPRCwastewater treatment facility and holding ponds. The sludge drying bed site is developed with the dryingbeds, associated levees, and pipes. The existing sludge drying pond area is designated as Support. TheCRPRC to the north of the drying ponds is designated as Academic and Administrative High Density andAcademic and Administrative Low Density. Open space agricultural fields lie directly to the east, west, andsouth of the sludge drying ponds and are designated as Teaching/Research Fields.

Proposed WWTP Site

The site for the proposed WWTP and solids storage basins (SSBs) is on the South Campus, eastof Old Davis Road and the Southern Pacific Railroad line, and ¼ mile north of the South Fork of PutahCreek. The site is bordered by pasture land and the California Center for Equine Health and Performance(CCEHP) facilities (e.g., paddocks, stables) to the south and east, Old Davis Road to the west, and openspace pasture land to the north. The Laboratory for Energy-Related Health Research facility (including theSouth Campus Disposal Site) is also located south of the site. The plant pathology fieldhouse and animalresources service facilities are located just west of Old Davis Road and the Southern Pacific Railroad line,west of the proposed site.

The 1994 LRDP designates the proposed WWTP site as Teaching/Research Fields. The 1994LRDP land use designations surrounding the site include Academic and Administrative Low Density (north,south, and west) and Teaching/Research Fields (east and west).

Agricultural Land Use

The 1990 Yolo and Solano Counties Important Farmland Map identifies the South Campus asPrime Farmland and Urban and Built-Up Land. The proposed WWTP site is identified as Prime Farmlandwhich is defined as land with the best combination of physical and chemical features for the production ofagricultural crops. Remaining undeveloped land in the Central Campus is identified as Prime Farmland orOther Land, which is defined as land that does not meet the criteria of any other category. See pages 4.1-28 and 4.1-29 and Figure 4.1-5 of the 1994 LRDP EIR for further discussion of prime farmland.

1994 LRDP Objectives

The 1994 LRDP includes the following resource objectives that relate to the proposed project:


n Putah Creek. Promote the maintenance of flows in Putah Creek (via dam releases andtreated Campus wastewater discharge) to sustain wildlife and the health of the Putah CreekCampus Reserve (Water Resources Objectives No. 4, page 16 of the LRDP).

n Cluster new development. Cluster new development identified for the West and SouthCampus with existing development (infill), or on the edges of agricultural areas, to retain larger,more useable blocks of agricultural land (Soils Resource Objective No. 2, page 26 of the 1994LRDP).

n Physical support systems. Continue use of independent Campus physical support systemssuch as water supply, wastewater treatment, solid waste disposal, and materials handling andprocessing (Developed Resources Objective No. 4, page 36 of the 1994 LRDP).

n Environmental and physical support systems . Expand and upgrade Campusenvironmental and physical support systems, such as the water management system and wastemanagement system, to ensure environmental health and enable Campus growth (Land UsePlan Objective No. 6, page 48 of the 1994 LRDP).

n Cluster like services. Provide sites on the South Campus to cluster support services thatmay benefit from co-location, such as warehouse and receiving facilities (Support Systems PlanObjective No. 3, page 72 of the 1994 LRDP).

n New wastewater treatment plant site. Identify a location for the new WWTP north of theproposed landfill expansion. Test the viability of shared environmental benefits for landfill andwastewater operations at this site, such as pooling methane gas byproducts from each facilityto create an energy source or using some of the new plant capacity to treat groundwatercontaminated by leaching from the existing landfill. (Support Systems Plan Objective No. 5,page 72 of the 1994 LRDP.)

n Riparian lands . Expand Open Space Teaching and Research lands to include all riparian andremnant riparian stretches of Putah Creek. This includes the new creek frontage at the RussellRanch (50 acres) and the North Fork Cutoff on the West Campus (20 acres). (Open SpacePlan Objective No. 1, page 76 of the 1994 LRDP.)





n propose uses that would conflict with locally adopted city or county planning policies;

n propose uses that would be incompatible with adjacent uses and that would be considered anuisance because the proposed use would (a) cause adjacent land uses to make extensiveoperational adjustments that would reduce the efficiency or effectiveness, or productivity of theland uses or (b) otherwise significantly adversely affect the efficiency, effectiveness, orproductivity of the land uses;

n propose uses that would convert or cause the conversion of prime farmland (as defined by theCalifornia Department of Conservation) to nonagricultural uses or cancel or cause thecancellation of Williamson Act contracts; or

n propose uses that would impair the agricultural productivity of prime agricultural land.


4.6-1 Development of the proposed WWTP on lands designated as Teaching/Research Fieldsis inconsistent with the land use designations in the 1994 LRDP. This impact isconsidered significant.

The proposed WWTP site is currently open space pasture land. The site is designatedTeaching/Research Fields in the 1994 LRDP. The proposed project would require an amendment to the1994 LRDP to change the land use designation of the proposed WWTP site from Teaching/ResearchFields to Support. The proposed project is consistent with 1994 LRDP resource objectives, and theproposed project does not conflict with any other local plans.

Mitigation Measure

Implementation of the following mitigation measure will reduce the impact to a less-than-significantlevel.

4.6-1 The Regents will amend the 1994 LRDP land use designation for the proposed WWTP sitefrom Teaching/Research Fields to Support.

4.6-2 Construction of the proposed WWTP would result in the displacement of the equinepasture being used by the CCEHP. This impact is considered potentially significant.

As discussed in the project description, the WWTP is proposed to be developed on approximately20 acres of land currently being used as three horse pastures by the CCEHP. The proposed project designincludes a new access road from Old Davis Road to the Main Compound of the CCEHP. A 5-foot-highirrigated landscaped berm with plantings is proposed along the north side of the proposed access road and


along the east side of the proposed WWTP next to the CCEHP Main Compound. The location of theproposed WWTP was selected in part based on proximity to the existing effluent pipeline and compatibilitywith existing land uses. The use and operation of the WWTP would result in the displacement of landcurrently being used as horse pasture; however, it would not contribute to any nuisance-related impacts onadjacent lands currently being used by the CCEHP. The displacement of the horse pasture with theWWTP is considered a potentially significant impact.

Mitigation Measure

Implementation of the following mitigation measure would reduce the impact to a less-than-significant level.

4.6-2 The Campus shall acquire a lease or purchase property immediately east of the CCEHP anddevelop replacement pasture.

4.6-3 The proposed WWTP could result in the development of land uses consideredincompatible with adjacent uses on Campus. This impact is considered less thansignificant.

The proposed project includes possible partial or complete demolition of the existing WWTP andremoval of the sludge drying ponds. The areas would be regraded and planted with grass cover. Thedecommissioning and demolition of the existing WWTP and sludge drying ponds would not affect adjacentland uses, such as the parking lot north of the site, Cole Facility (agricultural animal research facility) andhorse arena east of the site, or the Environmental Services Facility (soon to be relocated) that lies to thewest of the site. Decommissioning, demolishing, and replanting the existing WWTP and existing sludgedrying ponds would not affect adjacent land uses.

Campus land uses adjacent to the proposed WWTP site include CCEHP facilities (e.g., paddocks,stables), the Institute of Toxicology and Environmental Health facility, the plant pathology fieldhouse, andteaching and research fields. The proposed project is considered Support facilities and is compatible withthose existing uses in the adjacent areas designated for Academic and Administrative Low Density andTeaching/Research Fields and would therefore not result in conflict with adjacent land uses.

Mitigation Measure


4.6-4 The proposed WWTP could result in the permanent loss of about 20 acres of primefarmland from California Department of Conservation’s inventory. This impact isconsidered significant and unavoidable.

Development of the proposed WWTP site would result in the permanent conversion ofapproximately 20 acres of prime farmland currently used for field teaching and research to other uses.


Mitigation Measure


Once the proposed WWTP is constructed, the underlying soils would no longer be available foragricultural activities. The only approach available to mitigate this impact to a less-than-significant levelwould be to replace the lost agricultural land. Theoretically, this could be accomplished by removingexisting development from prime farmland or by purchasing developed land off Campus and converting itto agricultural lands (assuming the underlying soils are considered prime). The feasibility and expenseinvolved in such actions make this mitigation infeasible. However, the essentially agricultural activities of theCampus, both existing and planned, to some extent do mitigate the impacts related to conversion of primeagricultural lands. The Campus is a center for study of agricultural issues, with a particular emphasis onimproving the productivity of soils and the preservation of soils. Preservation of soils will continue to be anessential focus of the Campus into the foreseeable future. Some development will cause prime agriculturallands to be lost, but the net effect of recent and planned actions can be considered to compensate in somemeasure for the projected permanent loss of prime agricultural land. For example:

n In 1991, UC Davis acquired the Russell Ranch. This property added approximately 1,590acres of agricultural lands, most of which is Prime or Important Farmland, to the main campus.

n In 1992, the Campus dedicated the first 100 acres at the Russell Ranch to a project on Long-Term Research in Agricultural Sustainability (LTRAS). The initial design of this project is for100 years. The LTRAS project is expected to expand over 300 acres in the next few years.

n The LRDP includes as a resource objective the management of campus lands to benefit theSwainson’s hawk. A three-part program will be employed to preserve nest trees, convertcreek-side orchards to suitable open grassland foraging lands at Russell Ranch and assure azone along Putah Creek on the West Campus. See also the 1994 LRDP EIR MitigationMeasure 4.7-5 in the Biological Resources chapter of this EIR.

Despite the compensatory value of the above described activities, this significant impact cannot bereduced to a less-than-significant level unless developed prime agricultural lands are returned to theiragricultural status and uses. Such measures are considered infeasible and, therefore, this impact isconsidered unavoidable.



4.6-5 The proposed WWTP (20 acres), in conjunction with 1994 LRDP development (160 acres),would increase the permanent loss of prime farmland from the State Department ofConservation’s inventory to 180 acres. This impact is considered significant andunavoidable.

The 1994 LRDP EIR discusses and evaluates cumulative impacts of and mitigation measures forprime agricultural land conversion. An additional 20 acres of prime agricultural land would be convertedas a result of this project; however the impacts and mitigation measures remain unchanged. Therefore, noadditional analysis is required.

Mitigation Measure


4.6-6 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, could convert 1,207 acres of prime agricultural lands to urban uses(1,187 acres identified in the 1994 LRDP EIR plus 20 acres for the WWTP). This impactis considered significant and unavoidable.

CEQA Section 15355 defines cumulative impacts as those impacts stemming from the sum of theproposed project’s impacts when added to those from all other closely related, reasonably foreseeableprojects. The relevant set of reasonably foreseeable development projects would consist of the proposedproject plus all of the development anticipated under the 1994 LRDP plus development anticipated in thevicinity of the Campus (areas of Davis and unincorporated Yolo and Solano Counties) through the 1994LRDP planning horizon of year 2005. The 1994 LRDP EIR identified approximately 1,874 vacant acreswithin the City of Davis planning area. Of this amount, approximately 1,027 vacant acres within the Cityof Davis may be converted by development according to the City Planning Department’s April 1993 vacantlands survey. Loss of 20 acres of prime agricultural land for the proposed WWTP plus loss of 160 acresof prime agricultural land on campus in combination with 1,027 vacant acres of prime agricultural land inthe City of Davis represents a significant adverse impact. The Campus’ contribution to this cumulativeimpact would be approximately 15%.

Mitigation Measure



Chapter 4.7 Visual Quality/Aesthetics

INTRODUCTION

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), thisanalysis focuses on issues relating to compatibility of the proposed project with the South Campus andissues relating to light and glare. Potential impacts related to valued visual resources of the Central Campusand long-distance views were adequately addressed by the 1994 LRDP EIR.


Visual Context

Existing WWTP and Sludge Drying Ponds

The existing WWTP is located in the Central Campus area, south and west of the intersection ofLa Rue Road and Putah Creek Lodge Drive. It is situated in a developed portion of the Campus and issurrounded by university buildings. The university mail room and Fleet Services are to the west, the ColeFacility and horse arena are to the east, parking lots and Leach Hall lie across La Rue Road to the north,and the Arboretum Waterway lies to the south of the WWTP. A 6-foot-high cyclone fence surrounds theperimeter of the WWTP, and a row of mature redwood trees separates the WWTP site from La RueRoad. Views to and from the WWTP are limited because of the existing surrounding structures, fencing,and landscaping.

The four existing sludge drying ponds are just west of County Road 98 and south of the mainCalifornia Regional Primate Research Center (CRPRC) buildings and holding ponds. Fencing and maturetrees and brush along County Road 98 block most views of the sludge drying ponds from the road.


Proposed WWTP

The proposed WWTP would be situated on a 20-acre site on the South Campus, east of OldDavis Road and the Southern Pacific Railroad line, and 1/4 mile north of the South Fork of Putah Creek.The site is bordered by pasture land and the California Center for Equine Health Performance (CCEHP)main compound to the east and south, Old Davis Road to the west, and the Southern Pacific Railroadtracks and Animal Resource Services and open space pasture land to the north and east. The Institute forToxicology and Environmental Health (ITEH) and the former LEHR site and the SCDS area are locatedfurther south of the site. The plant pathology field house facilities are located just west of Old Davis Road,west of the site. The site is currently flat, open, pasture land. In general, the visual landscape east of OldDavis Road is agricultural and one-story research buildings; the west side of Old Davis Road is agricultural.



Appendix G of the CEQA Guidelines states that an impact is significant if a project has ademonstrable negative aesthetic effect, if it will result in obstruction of scenic vistas or views, or if it willcreate an offensive site open to public views. The focus of this visual analysis is on the relationship betweenthe proposed project and the surrounding visual environment.


n allow incompatible development in or near areas with high visual quality, such as Putah Creekand the Arboretum Waterway, or substantially affect the valued elements of the visuallandscape identified in the 1994 LRDP;

n result in structures that would disrupt views of surrounding agricultural lands, the Coast Range,or the Sierra Nevada; or

n create substantial new sources of artificial light and/or glare.


4.7-1 Structures built at the proposed WWTP could be incompatible with the existing ruralagricultural character of the South Campus. This impact is considered potentiallysignificant.



4.11-2 The Campus Design Review Board shall review proposed structures on theSouth and West Campuses and Russell Ranch to ensure that the design,setbacks, screening and landscaping will achieve compatibility with thesurrounding environment.

Approximately six buildings are necessary for operation of the proposed WWTP. Theadministration/maintenance building is the only building that will be occupied by employees. All proposedstructures would consist of one story or less (some structures would be partially below grade). Twostructures would be placed on a berm approximately 6-7 feet high. The top of the ultraviolet tank will beat grade with the top of the berm. The top of the filters will be approximately 20 feet above the top of theberm. (Mingee pers. comm.)

The perimeter fencing around the site would be set back from the access road to the CCEHP toallow for a berm and some screen plantings to soften the visual barrier of the fence. The effect of theplantings may be similar to the row of redwood trees that screens views of the existing WWTP from La RueRoad. At the proposed main plant entrance, the fence and gate are proposed to be set back from the roadboundary to lessen the visual impact of the gate on views from the road when the gate is closed.

The WWTP site design plans also include exterior lighting and landscaping. The design providesfor area lighting for security and illumination of roadway, parking, exterior building, and equipment areas. Pole- and wall-mounted light fixtures with high-pressure sodium lamps would provide exterior lighting inthe open areas. These lights would be designed to minimize glare (Mingee pers. comm.).

The landscape design concept for the WWTP site was developed in response to the following goals(Nolte and Associates 1995):

n The landscape treatment should enhance the facility both aesthetically and functionally.

n The landscaping should reinforce the agrarian imagery of the rural setting of the treatment plant. It should recognize the function of the treatment plant without trying to disguise or apologizefor it.

n The landscaping should extend the comfortable work environment for plant employees andvisitors to include as much of the site as possible, for as much of the calendar year as possible.

n The plantings should be designed to use water responsibly.

n All landscaping should emphasize ease of maintenance.


For the proposed WWTP site, screen plantings would be used at the main plant entrance, alongthe proposed access road to the CCEHP, and on the east side of the plant. The dominant element wouldbe a row of low-maintenance trees, similar in growth to orchard trees (nut or fruit) but lower in maintenance.

In compliance with the 1994 LRDP EIR Mitigation Measure 4.11-2, the Campus Planner and theCampus Architect, as representatives of the Design Review Board, have determined that the setbacks,screening, and landscaping for the proposed project would sufficiently screen the project from surroundingland uses. The landscaping would not conflict with the existing rural character of the area.

Compliance with 1994 LRDP EIR Mitigation Measure 4.11-2 will reduce this impact to a less-than-significant level.

Mitigation Measure


4.7-2 Structures built at the proposed WWTP could create glare, artificial light, heat, and shade,making the immediate area uncomfortable for people. This impact is consideredpotentially significant.


4.11-4(a) Prior to design approval of the first structure approved followingadoption of the 1994 LRDP, the Campus shall develop guidelines tominimize discomfort from light, heat, and glare.

The guidelines could include, but would not be limited to, buildingsurfaces, landscaping, orientation and exposure, and lighting.

4.11-4(b) Prior to design approval of any building, the Campus Design ReviewBoard shall assess the building design for compliance with the guidelinesdeveloped under Mitigation Measure 4.11-4(a).

Light reflecting off pavement, vehicles, and reflective or polished building materials can cause glare. During the day, the amount of glare depends on the intensity and direction of sunlight. At night, artificiallighting can cause glare. Interior and exterior lighting at the proposed WWTP would be directed at theparking area, buildings, and structures. The exterior lighting also would be designed to minimize glare.

Radiant heat from large, unshaded structures can affect passers-by and, in some circumstances,raise the ambient temperature. The wastewater would be processed in open-air structures, allowing watervapor to escape to the ambient air. The cooling effect of the ambient water vapor and the landscaping ofthe site would reduce the effect of radiant heat from the structures. During the cool winter months,


maximum exposure to the sun is desirable. In contrast, trees and buildings would provide shade in the hotsummer months.

In compliance with the 1994 LRDP EIR Mitigation Measure 4.11-4(b), the Campus Architect, asa Design Review Board representative, has reviewed the proposed project design to determine the potentialfor light, heat, and glare. The Campus Architect has determined that the proposed building materials willnot create light and glare in any means inconsistent with the existing character of the area. The UC DavisArchitects and Engineers Office has developed Campus standards for outdoor lighting that minimize glare,and these standards will be used at the WWTP site.

Compliance with 1994 LRDP EIR Mitigation Measures 4.11-4 (a) and (b) will reduce this impactto a less-than-significant level.

Mitigation Measure



4.7-3 The proposed WWTP, in conjunction with 1994 LRDP development, would contribute toan alteration of the rural agricultural character of the Campus. This impact is consideredpotentially significant.

As stated in the 1994 LRDP EIR, cumulative visual impacts, such as loss of open space andalterations to existing visual character, are considered at the level that can be generally characterized as awhole. For this analysis, cumulative impacts are analyzed in the context of the South Campus and theCampus as a whole. The proposed project represents urban development on the South Campus; additionalurban development is occurring on the Central Campus and West Campus. Undisturbed and agriculturalland is being converted to urban uses. As a result, open space on the Campus is being lost and thecharacter of the Campus is becoming more urban and less rural. The proposed WWTP would not resultin a significant loss of open space or alteration of the rural character of the South Campus or the Campusas a whole; however, it would contribute to these changes.


4.11-2 The Campus Design Review Board shall review proposed structureson the South and West Campuses and Russell Ranch to ensure that thedesign, setbacks, screening and landscaping will achieve compatibilitywith the surrounding environment.


Mitigation Measure


4.7-4 Cumulative development in the region, in conjunction with the proposed WWTP and 1994LRDP development, would contribute to a cumulative alteration of the rural character ofSolano County. This impact is considered significant and unavoidable.

For this analysis, cumulative impacts are analyzed against the expansive, rural character of Yolo andSolano counties. Urban development is occurring throughout this region. Undisturbed and agricultural landis being converted to residential and commercial uses. As a result, open space is lost and the rural characterof the counties is becoming more urban. While the proposed WWTP and 1994 LRDP development wouldnot result in a significant loss of open space or alteration of the rural character on the Campus, it wouldcontribute to these changes in the region.

The 1994 LRDP EIR identifies the following mitigation measures to reduce the magnitude of theidentified impacts; however, the feasibility and/or implementation of Mitigation Measure 4.11-5(b) cannotbe guaranteed by the University of California because it falls within other jurisdictions to enforce andmonitor. In addition, the conversion of undisturbed and agricultural land to urban uses is considered asignificant and irreversible alteration of the rural character of an area. For these reasons, the University mustconsider the impact as significant and unavoidable.

4.11-2 The Campus Design Review Board shall review proposed structureson the South and West campuses and Russell Ranch to ensure that thedesign, setbacks, screening and landscaping will achieve compatibilitywith the surrounding environment.

4.11-5(b) The City of Davis General Plan, Yolo County General Plan, andSolano County General Plan contain policies that address thepreservation and protection of agricultural land. It is within thejurisdiction of these agencies to implement the general plan policieswhich support the conservation of agricultural land and the prohibitionof new development in designated agricultural areas.

Mitigation Measure



Chapter 4.8 Noise

INTRODUCTION

As discussed in the second Notice of Preparation and the Revised Initial Study (Appendix A), thisanalysis focuses on noise impacts from transportation sources on structures that would be occupied on theproject site. The proposed project would not result in any new construction noise impacts that were notalready identified in the 1994 LRDP EIR. Mitigation Measure 4.4-1 in the 1994 LRDP EIR will beimplemented as part of the proposed project to mitigate any potential construction noise impacts. Also, asdiscussed in the Revised Initial Study, noise impacts associated with the operation of the facility areconsidered to be less than significant.

ENVIRONMENTAL AND REGULATORY SETTING

General Background and Overview

Definitions of terms used in acoustics, background information on environmental acoustics, andstate and federal noise guidelines and regulations are provided in Appendix I. The State of California andthe UC CEQA noise guidelines do not have specific standards for exterior noise levels (University ofCalifornia, Davis 1994). The only numerical guidance is in the State of California general plan guidelinesfor counties and cities for the preparation of noise elements. These guidelines are discussed in AppendixI. Noise compatibility guidelines recommended by the State are summarized in Figure 4.8-1.

Land Uses and Sensitive Receptors in the Project Vicinity

The project site is bordered by Old Davis Road, the Plant Pathology Fieldhouse area, andgreenhouses to the west; the Southern Pacific Railroad (SPRR) and pasture to the north; and pasture andthe California Center for Equine Health and Performance (CCEHP) to the east. Additional CCEHPfacilities are located to the south next to the Nutrition and Pet Care Center and the Comparative OncologyFacility. The LEHR/SCDS area, Putah Creek Road, and the South Fork of Putah Creek area also locatedsouth of the site. None of these existing facilities or uses are considered sensitive to noise.

Figure 4.8-1


Existing Noise Conditions

Ambient noise is the total noise in a given environment and usually comprises sounds from manysources both near by and far away. The primary sources of noise on and around Campus aretransportation facilities. Traffic on roads and highways, airplanes using the University airport, and trains arethe most common transportation sources. Noise from traffic on Interstate 80 and trains traveling on theSPRR track north of the project site are the primary sources of noise in the project area. Traffic on OldDavis Road is also a source of noise but to a much lesser degree. The project site is not substantiallyaffected by other miscellaneous sources of noise on the Campus, such as mechanical equipment systems,the Campus Airport, and waste handling facilities.

Noise monitoring was conducted in the project area east of Old Davis Road south of the LEHRsite on October 12, 1993, from about 10:18 a.m. to 10:23 a.m. as part of the 1994 LRDP EIR process. Sound levels in the range of 48 to 53 dBA were measured (University of California, Davis 1994). Themajor noise source was the freeway approximately one mile north. The measured sound levels indicate thatit is unlikely that any trains passed by during monitoring.



As stated in the 1994 LRDP EIR, an impact is considered significant if the proposed project would:

n cause substantial construction-related short-term noise level increases on the Campus, in YoloCounty, or in Solano County that would disturb or interfere with nearby noise-sensitive usesor exceed the City of Davis Noise Ordinance for receptors in the City of Davis. Such noise-sensitive uses include off-campus residences, campus housing, and high- and low-densityacademic and administrative facilities; or

n substantially increase the ambient noise levels for adjoining areas by 5 dBA during projectoperation, or cause noise levels to exceed normally acceptable levels as defined by the Stateof California general plan noise element guidelines for receptors on the Campus, SolanoCounty general plan guidelines for receptors off-campus within Solano County; Yolo Countygeneral plan guidelines for receptors off-campus within Yolo County; City of Davis generalplan guidelines for receptors off-campus within Davis; or Cal OSHA standards.

Additionally, according to CEQA Guidelines, a project will normally have a significant effect on theenvironment if it will:

n substantially increase the ambient noise levels for adjoining areas orn expose people to severe noise levels.


In practice, more specific professional standards have been developed to implement the intent ofthe CEQA guidelines. These standards state that a noise impact is considered significant if it would:

n generate noise that would conflict with local planning criteria or ordinances,n substantially increase noise levels at noise sensitive land uses, orn propose land uses that are incompatible with existing baseline noise levels.

As stated earlier, the State of California and the UC CEQA noise guidelines do not have specificstandards for exterior noise levels. The only numerical guidance is in the State of California general planguidelines (Figure 4.8-1). For this project, the significance of anticipated noise affects within Campusboundaries is based on a comparison between anticipated noise levels and the general plan compatibilityguidelines identified in Figure 4.8-1.


4.8-1 Occupants in structures developed under the proposed project would be exposed to noisefrom trains traveling on the Southern Pacific Railroad. This impact is consideredsignificant.


4.4-3(a) Prior to final project approval, the Campus shall evaluate each projectproposed under the 1994 LRDP for potential exposure to noise levelsexceeding 60 Ldn.

and

4.4-3(b) If individual projects would be exposed to noise levels between 60 Ldn and70 Ldn, the Campus shall undertake and implement the recommendationsof a detailed analysis of noise reduction features necessary to achieve aninterior noise level of 45 Ldn. It is anticipated that conventionalconstruction, but with closed windows and fresh air supply systems or airconditioning, would normally achieve the necessary noise attenuation.

The administration and maintenance building for the proposed WWTP would be located about 160feet from the SPRR tracks, which would result in the building and its occupants being exposed to noise fromtrain passages. The 1994 LRDP EIR provides projected traffic and train noise contours in the project areafor the year 2010. These contours have been transcribed on to the preliminary site plan of the proposedproject (Figure 4.8-2). The 65 dB-Ldn contour is governed by the trains on the SPRR track, and the 60dB-Ldn contour is governed by both trains and traffic on Interstate 80. Based on these contours, a largeportion of the project site is exposed to noise in excess of 60 dB-Ldn. The administration and maintenancebuilding would be exposed to train noise that is about 63 dB-Ldn. The State general plan land use


compatibility guidelines indicate that sound exposure as high as 70 dB-Ldn is normally acceptable for officebuildings.

Mitigation Measure


4.8-1 The Campus shall retain a qualified acoustical consultant to provide designrecommendations that will result in sound levels within the administration and maintenancebuilding from train passages of 45 dB-Ldn or less.

Because specific design features of the administration and maintenance building are not available,specific treatments to ensure that interior sound levels are below 45 dB-Ldn cannot be identified. However,the following discussion is intended to describe building design features that can typically be used to reduceinterior noise.

The effectiveness of a building shell in attenuating exterior noise is dependent on a number offactors, including:

n the size and extent of gaps, cracks, and other openings, such as those that occur around doors,windows, vents, and chimneys;

n the size, number, and transmission loss characteristics of windows and doors; and

n the type of building shell construction.

Approximately 18 to 20 dB of exterior to interior noise reduction will be required to reduce theinterior noise exposure from train passages to 45 dB-Ldn. Standard building construction will generallyprovide such a reduction. However, windows, building shell openings, and other penetrations that have adirect line of sight to the train track can reduce the effectiveness of the building shell in reducing noise levels.

The following are examples of measures that might be implemented to ensure good sound insulationof the building shell:

n design exterior wall and roof/ceiling assemblies with airtight construction to provide soundinsulation equivalent to a Sound Transmission Class (STC) rating of at least 50;

Figure 4.8-2


n avoid use of direct wall and roof penetrations into occupied areas that have a direct line-of-sight to the train track, such as mail slots, vents, and exhaust fans;

n avoid or minimize the use of windows and doors that have a direct line-of-sight to the traintrack;

n where doors have a direct line-of-sight to the train track, use door assemblies with an STCrating of at least 30 and use door jamb, head, and bottom gasketing to provide an airtight seal;

n where windows have a direct line-of-sight to the train track, minimize window size, use non-operable windows, use window assemblies with an STC rating of at least 30, and selectwindow assemblies with effective nonporous gaskets or weatherstripping to minimize airfiltration and sound leakage; and

n use permanently non-hardening sealant around window frame perimeters that have a direct line-of-sight to the track.


4.8-2 Cumulative development in the region, in conjunction with the proposed WWTP and 1994development, would result in increased traffic and other noise sources which could exposepeople and structures on- and off-campus to significant cumulative noise levels. Thisimpact is considered significant and unavoidable.

Development and growth on the Campus allowed under the 1994 LRDP, in conjunction with theproposed project and growth elsewhere in the City of Davis and the region, would result in higher levelsof noise. The 1994 LRDP EIR identified the following mitigation measure to reduce the magnitude of thisimpact; however, the feasibility and/or implementation of Mitigation Measure 4.4-4(c) cannot be guaranteedby the University of California because it falls within other jurisdictions to enforce and monitor. For thisreason, the University must consider the impact significant and unavoidable.

4.4-4(a) The Campus shall evaluate each project proposed under the 1994LRDP for its potential to create, or contribute to, noise levels whichexceed State of California general plan guidelines on Campus, SolanoCounty general plan guidelines within Solano County, Yolo Countygeneral plan guidelines within Yolo County, City of Davis general planguidelines within Davis, or Cal OSHA standards.

4.4-4(b) Implement Mitigation Measure 4.4-3(a) through (c).

4.4-4(c) (i) The Noise Element of the City of Davis general plan includesland use noise compatibility standards, as depicted in Figure 4.4-3


of the 1994 LRDP EIR. It is within the jurisdiction of the City ofDavis to implement the policies and standards found in the noiseelement.

(ii) The Noise Element of the Yolo County general plan includesland use noise compatibility standards, as depicted in Figure 4.4-2of the 1994 LRDP EIR. It is within the jurisdiction of the YoloCounty to implement the policies and standards found in the noiseelement.

(iii) The Noise Element of the Solano County general plan includesland use noise compatibility standards, as depicted in Figure 4.4-4of the 1994 LRDP EIR. It is within the jurisdiction of the SolanoCounty to implement the policies and standards found in the noiseelement.

Mitigation Measure


chapter 4.1 hydrology and water quality...university of california, davis 4.1-1 october 1996 chapter...

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