town of hayden wastewater treatment …...current asarco mine, kennecott copper corporation, in...

Section 208 Area Wide Water Quality Management Plan Amendment

TOWN OF HAYDEN WASTEWATER TREATMENT PLANT

AND COLLECTION SYSTEM PROJECT

April, 2011

Submitted to: Central Arizona Association of Governments

Table of Contents

SECTION 1.0 - INTRODUCTION ............................................................................................. 3 Section 1.1 - ABSTRACT ......................................................................................................... 3 Section 1.2 - PROJECT HISTORY .......................................................................................... 4

SECTION 2.0 - PROJECT DESCRIPTION ................................................................................ 6 Section 2.1 - OVERVIEW......................................................................................................... 6 Section 2.2 - SERVICE AREA DESCRIPTION ..................................................................... 7 Section 2.3 - MAKE UP OF SERVICE AREA ....................................................................... 7

SECTION 3.0 - WASTEWATER CHARACTERIZATION..................................................... 9 Section 3.1 - POPULATION ................................................................................................... 9 Section 3.2 - WASTEWATER FLOWS................................................................................... 9

SECTION 4.0 - WASTEWATER TREATMENT FACILITY ................................................. 12 Section 4.1 - TREATMENT FACILITY DESCRIPTION.................................................... 12 Section 4.2 - SEWAGE COLLECTION SYSTEM ............................................................... 13 Section 4.3 - EFFLUENT MANAGEMENT........................................................................ 16

SECTION 5.0 - CONSTRUCTION........................................................................................... 18 Section 5.1 - CONSTRUCTION SUMMARY ..................................................................... 18 Section 5.2 - PHASING.......................................................................................................... 18

SECTION 6.0 - IMPACTS.......................................................................................................... 19 Section 6.1 - ENVIRONMENTAL IMPACT....................................................................... 19

SECTION 7.0 - PERMITS .......................................................................................................... 22 Section 7.1 - AIR QUALITY PERMIT.................................................................................. 22 Section 7.2 - ADWR UNDERGROUND STORAGE FACILITY (RECHARGE) PERMIT AND RECOVERY WELL PERMIT...................................................................... 22 Section 7.3 - AQUIFER PROTECTION PERMIT (APP) ................................................... 22 Section 7.4 - AZPDES PERMIT ............................................................................................ 23 Section 7.5 - AZPDES CONSTRUCTION GENERAL PERMIT ...................................... 23 Section 7.6 - LOCAL FLOODPLAIN AND DRAINAGE REGULATIONS................... 23 Section 7.7 - RECLAIMED WATER REUSE PERMIT....................................................... 23 Section 7.8 - SLUDGE MANAGEMENT ............................................................................ 23

SECTION 8.0 - FINANCIAL INFORMATION...................................................................... 25 APPENDIX 1 – CWA 208 CHECKLIST APPENDIX 2 - EXHIBITS/FIGURES APPENDIX 3 - COMMUNICATIONS

Financial Capacity Letter from Mayor of Hayden & Financial Statement for Year Ending June 30, 2008 Sponsorship letter from Gila County

Sponsorship letter from Pinal County Letters of support from surrounding communities

APPENDIX 4 – REFERENCES

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SECTION 1.0 - INTRODUCTION The Town of Hayden, Arizona is requesting approval of an amendment to the Central Arizona Association of Governments (CAAG) Section 208 Area Wide Water Quality Management Plan (AWWQMP) for a proposed wastewater treatment facility (WWTP) to be located in Section 14, Township 5S, Range 15E of the Gila and Salt River Meridian, Gila County, AZ (Appendix 2, Figure 1: Vicinity Map). The Town is seeking a long-term, permanent solution to its wastewater disposal needs by constructing a wastewater treatment system that will meet Arizona Department of Environmental Quality (ADEQ) requirements. Hayden also seeks to upgrade and/or place existing wastewater pump stations and the existing collection and transmission systems to improve reliability and protect public health.

Section 1.1 - ABSTRACT The purpose of this plan amendment is to present 20-year wastewater needs, construction planning and technical information to allow CAAG to amend the current AWWQMP to include the siting and construction of a new wastewater treatment plant (WWTP) for the Town of Hayden (Appendix 2, Figure 2: County Location Map), upgrade or replace existing lift stations and replace existing gravity sewers and force mains. The WWTP will be owned and operated by the Town of Hayden, the Designated Management Agency (DMA) for areas within its incorporated boundary. Currently, the Town collects untreated domestic sewage from residences, commercial properties, and from some parts of Asarco’s Hayden Operations and pumps it to the reduction plant tailings line where it mixes with tailing water before it is pumped to nearby mine tailings piles on property owned by Asarco. The proposed wastewater treatment plant has a design capacity of 80,000 gallons per day (gpd) average daily flow and 200,000 gpd peak daily flow. It will treat the Town’s existing wastewater from residential and commercial properties as well as those non-industrial flows from Asarco’s operations. The new WWTP will be constructed on approximately 2.21 acres of previously Asarco-owned land that has been conveyed to the Town along with the necessary easements for Town access to the WWTP. The WWTP is being designed to meet ADEQ’s best available demonstrated control technology (BADCT) requirements for new facilities (A.A.C. R18-9-B201 and R18-9-B204). The plant is an extended aeration (e.g., modified activated sludge process) facility, capable of denitrification, which can be maintained and

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operated by the Town’s personnel. An 8,000 gallon equalization basin will be included in the plant design to accommodate fluctuations in the influent flow rate and provide for more uniform flow through the plant. Sludge will be dried onsite in two sludge drying beds before disposal. The plant will generate approximately 22 dry tons of sludge annually, which will be disposed of at an approved facility or may be used for mine reclamation projects. The new WWTP has been designed to produce Class B+ effluent, however, the effluent will not be reused but rather will be pumped to Asarco for use in its industrial processes. The use of reclaimed effluent in the industrial operations is not considered direct reuse under A.A.C. R18-9-701(1)(c) but rather is considered discharge under the APP program.

Note: A small portion of the Asarco Hayden Operations flows will not be conveyed to the new WWTP but rather will be treated with a new, small wastewater treatment plant that will be installed by Asarco on its property near the concentrator (Appendix 2, Figure 3: Proposed Layout). This small package plant will have a design capacity of approximately 6,800 gallons per day and treat domestic wastewater and shower water from several facilities including a shop, warehouse, administration building and change house. The plant will be an aerobic treatment system capable of meeting the same ADEQ requirements (A.A.C. R18-9-B204) as the Town’s WWTP. The discharge from this separate WWTP will also be pumped to Asarco for use in the industrial operations.

Section 1.2 - PROJECT HISTORY The Town of Hayden is a mining community that was established in 1909. Hayden was deeded its existing sewer collection system by then owner of the current Asarco mine, Kennecott Copper Corporation, in 1959, three years after the Town incorporated in 1956. The Town has no wastewater treatment and pumps untreated sewage to Asarco’s Primary Lift Station (PLS) (Appendix 2, figure 3). The wastewater is currently injected into the tailings disposal pipeline and conveyed to three tailing deposition areas. The tailings slurry is pumped around the periphery of the impoundments, and then collected from the central areas of the impoundments where it eventually ponds. This collected water is then conveyed by pipeline to basins adjacent to the pump station near the Hayden Golf Course and then pumped to storage tanks for eventual re-use in the industrial processes in the plant. The existing collection and conveyance system is in a degraded state and consists of substandard pipes, junctions, manholes and lift stations in need of replacement. The collection system was recently evaluated through use of a closed-circuit television (CCTV) system. A majority of the collection system was

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deemed inaccessible due to a lack of cleanouts, rugged terrain, grease/grit build up and the inability to locate or access manholes. As a result, only about 30% of the existing collection system has been evaluated by CCTV. The current collection system consists mostly of the original 1959 system, and is kept operational through on-going maintenance by the Town. The existing force main is also substandard and spans washes and ravines in the community with little to no structural support. The Town’s collection and conveyance system consists of both gravity mains and pressure mains all converging into the PLS (Appendix 2, Figures 3 and 9: Collection System Configuration). The concrete wet well serving the PLS, which injects the untreated wastewater into the tailings pipeline, suffers from severe concrete corrosion. The present collection system is difficult to maintain and operate due to its age and level of deterioration. One force main and associated LS 1, located near the intersection of San Pedro Avenue and SR 177, collects flows from the western side of town and pumps up to the PLS. A second force main and associated LS 3, serves the southeastern side of the town and pumps to the PLS. LS 3 and this force main are both in extremely poor condition. The steel pressure main is approximately 50 years old, is badly corroded and requires repeated repairs. The frequency of repair has accelerated in the past several years as corrosion continues to reduce the pipe wall thickness to unacceptable levels. LS 5 is located at the far eastern edge of the town, on the northwestern corner of SR 177 and Mountain View Road, and pumps through a 4-inch schedule 40 PVC force main back to LS 3 and then up to the PLS.

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SECTION 2.0 - PROJECT DESCRIPTION

Section 2.1 - OVERVIEW 2.1.1 Facility Ownership The new WWTP, list stations and sewage collection systems will be owned by the Town of Hayden. The site for the WWTP was previously owned by Asarco who has conveyed the 2.21 acre site and necessary easements/rights-of-way to the Town. A legal description of the site is provided in Appendix 2 - Legal Description. 2.1.2 Type of facility The WWTP is as an extended aeration (e.g., modified activated sludge process) facility, capable of denitrification, with a designed capacity of 80,000 gpd. The plant will include a bar screen/grinder, influent pump station, flow equalization, anoxic basin and mixer, aeration basin and air diffusers, mixed liquor recycle pump, clarifier, aerobic sludge digester, chlorine contact/dechlorination basin, effluent storage and an effluent pump station Sludge dewatering will be achieved using sludge drying beds at the facility. The layout of the facility is presented in Appendix 2, Figure 5: WWTP Site Plan. 2.1.3 Build-out capacity The WWTP plant will have a capacity of 80,000 gallons per day (gpd) average daily flow and 200,000 gpd peak daily flow after system start-up. 2.1.4 Service area The WWTP and sewage collection system will serve only the residences and businesses within the incorporated limits of the Town (1.3 square mile service area or approximately 832 acres) consistent with its current DMA service area (Appendix 2, Figure 2). Note: Flows from a small portion of Asarco’s industrial operations will not be treated in the Town’s new WWTP but, rather, will be served by a new, small package WWTP that Asarco will install on Asarco property (see Section 1.1).

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Section 2.2 - SERVICE AREA DESCRIPTION 2.2.1 Location The WWTP will serve the Town of Hayden in Gila County, Arizona.

A. Legal The legal description of the facility is provided in Appendix 2, Legal Description but is generally a portion of the northwest quarter of Section 14, Township 5 South, Range 15 East in the G&SRBM.

B. Designated Management Area (DMA) The Town of Hayden was designated as the DMA in 1978. The WWTP site, sewage collection system and lift stations are all entirely within the Town limits and within the Town’s current DMA service area which corresponds to the town’s incorporated boundary (Appendix 2, Figure 2).

C. Neighboring Communities This new WWTP is located in the southern portion of Gila County, AZ. Hayden is approximately 1.3 miles northwest of the Town of Winkelman, 6.3 miles northwest of Dudleyville and approximately 10 miles southeast of Town of Kearny. The Pinal County line is approximately 1,700 feet from the proposed site of the Hayden WWTP (Appendix 2, Figure 3). 2.2.2 Size of the service area As noted in Section 2.1.4, the WWTP will have a service area of approximately 1.3 square miles.

Section 2.3 - MAKE UP OF SERVICE AREA 2.3.1 Number of dwelling units and consumers serviced at build-out According to the 2000 Census, there were 288 occupied households within the Town limits. The 2009 estimate of persons per dwelling unit is approximately 3.0. The Town estimates it currently has approximately 350 sewer hookups which include residential and commercial flows from the town and some non-industrial wastewater from Asarco’s Hayden Operations.

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2.3.2 Land Use-Existing and Projected

A. Residential, commercial, etc.

The Town of Hayden does not have an adopted General Plan. However, a land use map was prepared for the town by David Evans and Associates in 1959 includes the following land use designations: Transportation, Utilities, Industry, Public Buildings, Open Space and Retail/Business. The land use map indicates the site for the new WWTP is designated for “industrial” use. The Town of Hayden Zoning Code was originally prepared January 19, 1959, and amended in 1962, 1970, and December 1991. The land is currently not zoned because mines comprised of five or more contiguous commercial acres are exempt from zoning requirements per Arizona Revised Statutes (A.R.S.) § 11-830. The Town considers the site’s current land use designation of “industrial”, appropriate for the new WWTP.

B. Density

Based on 288 dwelling units and the Town’s 1.3 square miles (832 acres), the dwelling unit per acre density is 0.346 units per acre. According to the 2000 census the population of the Town of Hayden was 892, making the population density at that time 686 persons per square mile (1.1 persons per acre).

C. Ownership of land

The plant will be constructed on approximately 2.21 acres of land that has been conveyed by Asarco to the Town along with the necessary easements/rights-of-way for access to the WWTP. Portions of the existing and new force main pipeline will be located on land owned by Asarco who has granted the Town rights-of-way/ easements to construct and maintain the lines. The lift stations and gravity lines will be located on land owned by the Town.

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SECTION 3.0 - WASTEWATER CHARACTERIZATION The only source of wastewater to the new Hayden WWTP will be from residential and commercial customers within the incorporated area of the Town including some non-industrial waste streams from the Asarco Hayden Operations.

Section 3.1 - POPULATION 3.1.1 POPTAC figures POPTAC figures for the Town of Hayden indicate a current population of 865. 3.1.2 Initial population serviced The initial population to be served by the WWTP is estimated to be the approximately 350 current service connections on the existing sewage collection system. This would include the population of the Town of Hayden, approximately 865 persons, plus commercial businesses and non-industrial wastewater from a portion of Asarco’s Hayden Operations. This WWTP will only treat municipal and domestic wastewater. No industrial waste will be treated. 3.1.3 Population at build-out

The population at build out is estimated to be approximately the same as the current service connections: 350. 3.1.4 Population projection According to the U. S. Census Bureau, the population of Hayden was 892 in the year 2000. The population in Hayden has been steadily declining by an average rate of 1-2% per year from 2000 to 2007, with an average 3.5% decrease in population from 1997 to 2000. Population growth/decline in mining communities is largely dependent on the mining industry. There are no known plans for the mine to cease operations in the foreseeable future.

Section 3.2 - WASTEWATER FLOWS 3.2.1 Flow capacity at build-out The proposed package plant will be sized to accommodate 80,000 gpd average daily flow and 200,000 gpd peak daily flow. The plant has not been designed

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with additional “freeboard” as the Town of Hayden has been experiencing a declining population. While operations at the Ray Mine might increase in the future, the trend in mining is to produce more ore with less labor so a significant increase in the work force is not anticipated. As a failsafe, the APP will include a requirement that when flows reach 90%, the Town begin planning for expansion. 3.2.2 Brief explanation of calculations Daily flow calculations are based on a combination of “Unit Design Flows" from Table 1, A.A.C. Title 18, Chapter 9, current population estimates and a comprehensive survey of local commercial flows (Appendix 2, Table: Town of Hayden APP Design Flows). As there is no current wastewater system, flow estimates were based on estimated flows from resident population plus commercial customers within the service area. Residential flows are assumed to be 80 gallons per day per person. The U.S. Census Bureau estimate of population for the Town of Hayden for 2007 was 821 for a calculated design flow requirement of 65,680 gpd average daily design flow. Commercial flows will come from a variety of sources including municipal services (e.g., police, fire, library, community pool), bars and restaurants, churches, several retail stores and non-industrial flows from Asarco’s facilities. Commercial flows reported by Asarco and the Town amount to an additional daily flow of 13,110 gpd, totaling 78,790 gpd. The service area was divided into four collection areas – that area flowing to lift station 1 (LS1), that area flowing to the primary lift station (PLS), that area flowing to lift station 3 (LS3) and the area flowing to lift station 5 (LS5). Flows were based on the number of dwelling units per collection area and either the average number of persons per household or characteristics of the commercial enterprises. 3.2.3 Contingency for peak flows Peaking factors are used in design for a variety of reasons including the accommodation of wet weather inflow and infiltration. Different peaking factors were applied within the four collection areas, based on the upstream population (A.A.C. R18-9-E301(D)), with an overall average peaking factor of 2.5. This resulted in a peak daily flow of 200,000 gpd.

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3.2.4 Flow phasing The new Town of Hayden WWTP will be built in a single phase. The sewage collection system improvements will be permitted and constructed in advance or simultaneously with construction of the new WWTP.

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SECTION 4.0 - WASTEWATER TREATMENT FACILITY

Section 4.1 - TREATMENT FACILITY DESCRIPTION 4.1.1 Type of Wastewater Treatment Facility The WWTP is as an extended aeration (e.g., modified activated sludge process) facility, capable of denitrification that will meet all BADCT requirements for new sewage treatment facilities. 4.1.2 Location of WWTP – physical address and/or legal description The legal description is a portion of the northwest quarter of Section 14, Township 5 South, Range 15 East, G&SRBM (Appendix 2, Figure 3). 4.1.3 Flow Rate The proposed package plant will be sized to accommodate 80,000 gallons per day (gpd) average daily flow and 200,000 gpd peak daily flow. 4.1.4 Sewage accepted by WWTP

A. Type The new WWTP will treat wastewater consisting of flows primarily from residential and commercial areas as well as the existing flows from Asarco Hayden Operations currently utilizing the sewage collection system. Note: Flows from a small portion of Asarco’s industrial operations will not be treated in the Town’s new WWTP but, rather, will be served by a new, small package WWTP that Asarco will install on Asarco property (see Section 1.1).

B. Projected percentage of amount per sewage type

The wastewater flow composition of the service area is approximately 92% residential and 8% commercial. There will be no industrial contribution to the wastewater flows to the new Hayden WWTP.

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Section 4.2 - SEWAGE COLLECTION SYSTEM 4.2.1 Description of sewer works infrastructure including

A. Sewer lines flowing into plant

The Town’s wastewater is collected and conveyed, by a network of gravity sewers and force mains, to the Primary Lift Station (PLS). Flow patterns for the new system will remain the same. The current collection system configuration is shown in Appendix 2, Figure 9: Collection System Configuration. The existing collection and conveyance system is in extremely poor condition and needs to be replaced in its entirety. A new discharge pipe to convey treated effluent to the Asarco Hayden Operations will also be required (Appendix 2, Figure 4: Proposed WWTP Effluent Discharge to Asarco). ADEQ permits are required for each of these new sewage collection system components.

B. Lift stations There are currently three lift stations, each needing significant rehabilitation or total replacement. The Primary Lift Station (PLS) will serve as the effluent pump station for the new WWTP (Appendix 2, Figures 3 and 9). In addition, a backup generator will be located at the PLS in the event of a power outage.

C. Any setbacks or easements that may be needed to create infrastructure

A.A.C. R18-9-B201 requires appropriate setbacks from the treatment and disposal components of the WWTP to the nearest adjacent property line. For an 80,000 gpd WWTP, the setback is 50 feet if full noise, odor and aesthetic controls are installed; otherwise the setback is 350 feet. The topography of the site is not conducive to siting the WWTP to meet the 350 feet setback from all adjoining properties. Therefore, the odor producing components of this facility, the flow equalization basin and the sludge digesters, will be equipped with aluminum covers. The covers will be exhausted to an activated carbon scrubber, which will remove odors from the air before it is discharged. The blowers and other equipment will be located within a walled enclosure. (Appendix 2, Figure 10: Noise and Odor Control Setback Limits) As noted in earlier sections, the new WWTP will be constructed on a 2.21 acre site conveyed to the Town by Asarco with necessary easements/rights-of-way to access the site for operations and maintenance. Asarco has also granted

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easements/ rights-of-way to the Town for any infrastructure (e.g., force mains, gravity lines) that may require crossing its property.

D. Other items pertinent to infrastructure issues Flood insurance rate maps, maintained by the Federal Emergency Management Agency (FEMA), were reviewed for this report. No improvements will be located within the 100-year floodplain (Appendix 2, Figure 7: Floodplain Map and Figure 8: FIRM Map 3). The summary of the findings is presented below.

The WWTP, PLS and LS 3 are located outside the 0.2% Annual Chance Flood Hazard area;

LS 5, located near the town boundary between Hayden and Winkelman, is on the border of a 0.2% Annual Chance Flood Hazard area;

The proposed force main from the WWTP to the existing connection outside of the SR 177 ROW, and existing LS 1 (furthest west) are located in Zone X – Areas of 0.2% Annual Chance Flood Hazard.

Note: The 0.2% Annual Chance Flood Hazard is defined as an area subject to possible inundation by 500-year flooding; an area subject to inundation by 100-year flooding with average depths of less than one foot or with drainage areas less than one square mile; or an area protected by levees from 100-year flooding.

4.2.2 Treatment process

A. Treatment type The WWTP is as an extended aeration (e.g., modified activated sludge process) facility, capable of denitrification, which can be maintained and operated by the Town’s personnel. Extended aeration is a modification of the activated sludge process which provides biological treatment for the removal of biodegradable organic wastes under aerobic conditions. Mixing is performed and air is supplied to maintain contact between microbial organisms and dissolved organics and to provide oxygen to sustain the aerobic biological processes. In addition, pH is controlled to optimize the biological process and the essential nutrients that must be present to facilitate biological growth and the continuation of biological degradation. Extended aeration systems require seed sludge, usually obtained from other similar wastewater treatment plants, to initiate the microbial treatment process. An 8,000 gallon equalization basin will be included in the plant design to accommodate fluctuations in influent flow rate and provide for more uniform flow through the plant.

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Extended aeration systems are easy to operate, are a well established technology, and are efficient at handling organic loading and flow fluctuations. They have lower capital costs, are easy to construct, are relatively odor free and have lower sludge yields compared to other treatment technologies. Extended aeration WWTPs have limited flexibility to adapt to changing effluent requirements and have longer aeration periods, which require more energy and longer treatment times compared to other technologies. Given the advantages and minor disadvantages, extended aeration is the technology of choice for many smaller communities throughout the state – especially those with little variation in waste streams.

B. Treatment monitoring The Town of Hayden will comply with all monitoring requirements in the individual Aquifer Protection Permit to be issued by ADEQ. This will include effluent monitoring (both during the start-up and normal operations) and, if required, groundwater monitoring (both ambient and during the operation of the WWTP) at the Point of Compliance (POC).

C. Odor control Extended aeration technology tends to have less odor issues than many other treatment technologies.

D. Stages The plant will include a bar screen/grinder, influent pump station, flow equalization, anoxic basin and mixer, aeration basin and air diffusers, mixed liquor recycle pump, clarifier, aerobic sludge digester, chlorine contact/dechlorination basin, effluent storage and an effluent pump station. E. Sludge processing Two sludge drying beds will be constructed at the facility. The drying beds, shown in Appendix 2, Figure 5, are sized based on estimated sludge volumes. F. Disinfection Chlorination will be used to reduce pathogens in the effluent to the required BADCT levels for secondary treatment for a new facility with flows <250,000 gpd per A.A.C. R18-9-B204.B.4. The WWTP will also have dechlorination capabilities, if needed, prior to sending the effluent to the Asarco Hayden Operations.

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G. Any other issues in the treatment process None known 4.2.3 Effluent – Collection, Storage and Disposal The effluent generation rate will be approximately equal to the incoming flow rate. There are no current plans for storage of effluent at the plant site. Treated effluent from the WWTP will be directed to a new effluent pump station which, in turn will pump treated effluent into the new discharge conveyance line to the Asarco Hayden Operations. In the future, the Town may consider use of the reclaimed water for allowable Class B+ uses such as golf course irrigation. 4.2.4 Sludge – Collection, Storage and Disposal Sludge will be dried in two sludge drying beds. The plant will generate approximately 22 dry tons of sludge annually, which will be disposed of in an approved facility or used for mine reclamation. Currently the Town is looking to convey the dried sludge to the Apache Junction Landfill, approximately 50 miles north of the Town. The Town may also consider using other approved facilities either in Gila or Pinal Counties.

Section 4.3 - EFFLUENT MANAGEMENT 4.3.1 Discharge

A. Effluent Quality The WWTP will treat wastewater to meet BADCT requirements for a new facility (A.A.C. R18-9-B201 and R18-9-B204). The WWTP is designed to achieve permit limitations listed below:

Five-day biochemical oxygen demand (BOD5) less than 30 mg/l (30-day average) and 45 mg/l (seven-day average), or carbonaceous biochemical oxygen demand (CBOD5) less than 25 mg/l (30-day average) or 40 mg/l (seven-day average);

Total suspended solids (TSS) less than 30 mg/l (30-day average) and 45 mg/l (seven-day average);

pH maintained between 6.0 and 9.0 standard units; and A removal efficiency of 85 percent for BOD5, CBOD5, and TSS;

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Total nitrogen of less than 10 mg/l (five-month rolling geometric mean.)

The concentration of fecal coliform organisms in four of the wastewater samples collected during the week is less than 200 cfu/100 ml or the concentration of E. coli bacteria in four of the wastewater samples collected during the week is less than 126 cfu/100 ml, based on a sampling frequency of seven daily samples per week;

The single sample maximum concentration of fecal coliform organisms in a wastewater sample is not greater than 800 cfu/100 ml or the single sample maximum concentration of E. coli bacteria in a wastewater sample is not greater than 504 cfu/100 ml

Any and all constituents that have established numeric Aquifer Water Quality Standards (AWQS) must be in concentrations less than the respective numeric AWQS in the treated wastewater. In addition, disinfection byproducts (trihalomethane compounds) should be eliminated by using dechlorination.

B. Discharge Location(s) The effluent will be pumped into a new discharge line leading to the Asarco Hayden Operations (Appendix 2, Figure 4).

C. Schedule of discharge (constant discharge vs. seasonal discharge) Discharge will take place year-round. 4.3.2 Reclamation/Reuse The Town is not currently proposing to reuse the treated effluent. The treated effluent will be pumped to Asarco for use in its industrial processing operations. The use of treated effluent by Asarco in its industrial operations is not considered direct reuse under A.A.C. R18-9-701(1)(c) but rather is considered discharge under the APP program.

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SECTION 5.0 - CONSTRUCTION Section 5.1 - CONSTRUCTION SUMMARY 5.1.1 Time frame for construction Design plans have been finalized and permit applications have been submitted to ADEQ. Construction contracts will be competitively bid once USDA confirms the funds are available for the Town to draw on – current estimate is winter, 2011. Construction contracts for WWTP and collection system improvements will be bid separately and may be awarded to separate vendors. Construction of the WWTP and collection system is estimated to take 6 – 8 months.

Section 5.2 – PHASING 5.2.1. Phasing benchmarks None 5.2.2. Phase time table None

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SECTION 6.0 - IMPACTS

Section 6.1 - ENVIRONMENTAL IMPACT 6.1.1 Known Water Quality Issues Aquifer Water Quality The Lower San Pedro Groundwater Basin extends from just north of Benson to its confluence with the Gila River near Winkleman and then runs north by northwest until it exits the basin near Kelvin. The entire basin has a predominantly rural landscape with small scattered settlements. Large tracts of land are used for irrigated agricultural and livestock grazing, however in the vicinity of Hayden, mining is the major economic activity with the open-pit copper mine at Ray and the smelter at Hayden. Depth to groundwater in the Hayden area is generally less than 50 feet and in many areas as shallow as 25 feet. The town receives its water from Asarco whose source is shallow wells in the floodplain aquifer. The floodplain aquifer is recharged primarily by surface water flows from the Gila River and results in some seasonal fluctuations. The ADEQ Open file report “Ambient Groundwater Quality of the Lower San Pedro Basin (July, 2002) found water quality in the floodplain aquifer near Hayden as meeting primary MCLs but having exceedances of the secondary or aesthetic based standards namely for total dissolved solids, sulfate, iron, manganese and fluoride. Generally these same constituents were found in downstream wells at slightly higher concentrations (e.g., near Kearny) Sources of these contaminants include recharge from historic mining (e.g., tailings), mineralized springs and irrigation return flows from upstream agriculture. Surface Water The Gila River is perennial in the vicinity of Hayden having entered the basin from the San Carlos Reservoir upstream. The Gila River joins the San Pedro near Winkleman and flows north and west for approximately 15 miles before leaving the basin near Kelvin. The San Pedro from Aravaipa Creek to the Gila River is on ADEQ’s list of impaired water for Escherichia coli and selenium. The Gila River from its confluence with the San Pedro to Mineral Creek is impaired for suspended sediment. Mineral Creek, at the site of the Ray Mine, is impaired for copper, selenium and low dissolved oxygen. The sources of these contaminants are similar to those causing aquifer impairments in addition to natural background.

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6.1.2 Point Source Pollution There are no point source pollution issues. Both the Towns of Winkleman and Kearny have AZPDES permits for discharges to the Gila River from their wastewater treatment facilities. 6.1.3 Non-Point Source Pollution There are no non-point source pollution issues related to the WWTP. The WWTP will be protected from stormwater impacts through proper site grading. As noted above, historic mining and agriculture have contributed to water quality impacts in the vicinity of this plant including miles of tailings adjacent to the Gila River and agricultural return flows upstream. 6.1.4 Soil Erosion There are no known existing soil erosion issues in the project area. No soil erosion issues are anticipated due to the installation of the WWTP. Best Management Practices (BMPs) identified in the Stormwater Pollution Prevention Plan (SWPPP), required as part of the AZPDES General Permit for Stormwater Discharges from Construction Activities, will be used during construction activities to minimize any soil erosion issues. 6.1.5 Air Quality The Town of Hayden is located in PM10 (particulate matter of 10 micrometers or less) and Sulfur Dioxide Nonattainment Areas. Although the Town will be required to demonstrate conformity with the State Implementation Plan (SIP) for both contaminants, the new WWTP construction and operations should not impact the emissions limits for particulate matter or sulfur dioxide. ADEQ’s Air Quality Division (AQD) has been informed of the Town’s plan and has advised them accordingly. 6.2 Community Impacts 6.2.1 Service/Infrastructure There are no Sanitary Districts within the proposed planning or service area. The closest treatment system is the Town of Winkleman to the south. The two communities negotiated for several years on the option of connecting Hayden to the Winkleman system. However, no agreement was ever reached and the Town of Hayden has elected to proceed with its own system. The WWTP will serve all of the Town as well as non-industrial wastewater from portions of the Asarco

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Operations. Remaining non-industrial flows from a small portion of Asarco’s operations will not be treated in the Town’s new WWTP but, rather, will be served by a new, small package WWTP that Asarco will install on Asarco property (see Section 1.1). There have been discussions of creating a regional wastewater system linking the communities of Kearny, Hayden, Winkleman and possibly Dudleyville. Those discussions will continue but are likely not a viable alternative for a number of years. Kearny is nearly 10 miles northwest of Hayden. The cost of piping alone would far exceed the available funding for this project. 6.2.2 Residential/Commercial No negative environmental impacts are anticipated for the residential or commercial areas. Properly managed, the WWTP should have minimal odor issues and no vector issues.

6.2.3 Economic Construction of a wastewater treatment facility will be beneficial to the community and minimize public health issues related to possible spills of raw sewage due to the deteriorated conditions of the collection system. Construction of the WWTP will provide jobs in Gila and Pinal Counties. 6.2.4 Recreation Construction of the WWTP will not provide any new opportunities or changes to water-based recreational uses, no impact to available recreational uses in the area, or changes in land use due to this project.

21

SECTION 7.0 - PERMITS The following permits will be required for the design, construction and operation of the new Town of Hayden WWTP and collection system and Asarco’s small package WWTP (see Section 1.1).

Section 7.1 - AIR QUALITY PERMIT The Town of Hayden will require Air Quality Permits for generators or motors exceeding 325 horsepower as required by the Arizona Administrative Code and EPA’s New Source Performance Standards (NSPS.) In general, stationary compression ignition internal combustion engines manufactured after April 1, 2006 and spark ignition engines powered generators manufactured after January 1, 2009 require permits from the Department. All permits will be obtained through ADEQ’s Air Quality Permitting Section.

Section 7.2 - ADWR UNDERGROUND STORAGE FACILITY (RECHARGE) PERMIT AND RECOVERY WELL PERMIT There are no planned underground storage facilities; therefore, no permit is required.

Section 7.3 - AQUIFER PROTECTION PERMIT (APP) 7.3.1 Individual Aquifer Protection Permits The new WWTP is a categorical discharging facility, and therefore, must obtain an individual APP for operation and closure (ARS § 49-241 (B)(10)). An APP application for the WWTP was submitted in September 2010. The APP for Asarco’s Hayden Operations (P-100507) will also require amendment to allow the treated effluent from the Town’s new WWTP to be conveyed for use in Asarco’s industrial operations. The eventual disposal through the tailings line will be addressed in Asarco’s permit amendment. Asarco filed for this amendment in September, 2010. Asarco will also need to amend the APP (P-100507) to include the new small package WWTP (see Section 1.1). Disposal of the treated effluent from this separate facility will also be used in Asarco’s industrial operations.

22

7.3.2 General Permits (GP) for Sewage Collection Systems The repair and/or installation of sewage collection system components including lift stations, gravity lines and force mains will require a Type 4.01 General APP from ADEQ. A construction authorization is required prior to initiating construction. Once the construction is complete, a discharge authorization is issued before the system can be put into service. The Town filed an application for the collection system in November, 2010.

Section 7.4 - AZPDES PERMIT An AZPDES Individual Permit is not required as there are no discharges to Waters of the United States.

Section 7.5 - AZPDES CONSTRUCTION GENERAL PERMIT As site disturbance will be greater than one acre, an AZPDES General Permit for Stormwater Discharges from Construction Activities will be required during the construction of the WWTP. In accordance with the AZPDES Construction General Permit, the contractor must develop and implement a SWPPP to address stormwater discharges from the WWTP construction site.

Section 7.6 - LOCAL FLOODPLAIN AND DRAINAGE REGULATIONS All improvements will be outside of the 100-year flood plain so a Floodplain Permit is not required. (Appendix 2, Figure 8).

Section 7.7 - RECLAIMED WATER REUSE PERMIT The Town is not currently proposing to reuse the treated effluent. The treated effluent will be pumped to Asarco for use in its industrial processing operations. The use of treated effluent by Asarco in its industrial operations is not considered direct reuse under A.A.C. R18-9-701(1)(c) but rather is considered discharge under the APP program. Section 7.8 - SLUDGE MANAGEMENT Part 503 of the Clean Water Act and A.A.C. R18-9 specify the quality of sludge that may be applied to land, distributed and marketed, placed in a sludge disposal facility, or incinerated. As noted, the sludge generated from the proposed WWTP will be dewatered and stored in onsite drying beds. It is anticipated that the dried sludge will be disposed of at an ADEQ certified landfill

23

after meeting testing requirements for quality. If the sludge is to be for mining reclamation projects or as soil enhances, additional requirements include registering the land applications sites with ADEQ’s biosolids/sludge management program.

24

25

SECTION 8.0 - FINANCIAL INFORMATION Design, engineering, and construction for the Town of Hayden’s collection system improvements and the new treatment facility are estimated at $4,705,000. The Town has accepted $565,000 in loans and $4,140,000 in grant funds from the U.S. Department of Agriculture – Rural Development Program. Loans will be repaid through a mixture of sewer service fees, debt repayment and general fund contributions. As part of the scoping for the project, the Town commissioned its consultant to conduct a rate study. The current rate schedule is graduated based on usage and ability to pay the fees. Due to the financial challenges faced by many of Hayden’s residents, the Town has been subsidizing the sewer rates out of the general fund. It is estimated that, based on the projected project cost, the sewer rates will likely double. Many of the town residents will be adversely impacted by a rate increase of this magnitude so it is likely the Town will continue to subsidize the system to some degree. The town increased its current rates in April 2009 and will increase them again before the end of construction. The Town currently pays approximately $155,000 in annual operation and maintenance (O&M) activities. O&M for the new facility is anticipated to be approximately the same because it will include new activities not required with the current disposal method. The items include sludge hauling, effluent testing, annual registration fees and increased operator salaries. It is anticipated that actual maintenance and repair will be significantly lower as a result of the new treatment plant and rehabilitated collection system. Appendix 3 contains a letter signed by the mayor for the Town that provides documentation of the Town’s financial capability to operate and maintain the proposed WWTP as well as a financial statement for fiscal year ending June 2008.

APPENDIX 1 – CWA 208 CHECKLIST

208 CHECKLIST Section 208 of the Clean Water Act1

40 CFR § 130.62

REQUIREMENT

PROVIDE BRIEF SUMMARY OF HOW

REQUIREMENTS ARE ADDRESSED

ADDRESSED ON PAGE:

AUTHORITY

1. Proposed Designated Management Agency (DMA) shall self-certify that it has the authorities required by Section 208(c)(2) of the Clean Water Act3 to implement the plan for its proposed planning and service areas. Self-certification shall be in the form of a legal opinion by the DMA or entity attorney.

The Town of Hayden was designated the DMA in 1978

7

1 FWPCA § 208 (Federal Water Pollution Control Act, commonly known as the Clean Water Act), 33 U.S.C. § 1288, Areawide waste treatment management 2 40 CFR § 130.6, Water quality management plans 3 FWPCA § 208; 33 U.S.C. § 1288(c)(2)

REQUIREMENT



ADDRESSED ON PAGE:

20-YEAR NEEDS

2. Describe existing WWT facilities.

The Town has no wastewater treatment and pumps untreated sewage to the nearby mine tailings pile on property owned by Asarco. Asarco’s Aquifer Protection Permit (APP-100507) for its Hayden Operations contains a compliance schedule that requires a plan to cease disposal of untreated sewage on Asarco property by August 2010. Construction of the new WWTPs will satisfy Asarco’s requirement and provide the needed treatment for the community

3-4

3. Show WWT certified and service areas for private utilities and sanitary district boundaries if appropriate.

No other providers in the area

N/A

4. Provide POPTAC population estimates (or COG-approved estimates only where POPTAC not available) over 20-year period.

POPTAC figures for the Town of Hayden indicate a current population of 865. The town has been experiencing a slight decline in population – 3% over the past decade

9

5. Provide wastewater flow estimates over the 20-year planning period.

Capacity figures for the 20-year horizon (80,000 gpd) are based on the existing population and little change in employment numbers at Asarco’s Hayden Operations

9-10

REQUIREMENT



ADDRESSED ON PAGE:

6. Illustrate the WWT planning and service areas.

Incorporated boundaries of Town of Hayden

Appendix 2, Figure 2

7. Describe the type and capacity of the recommended WWT Plant.

The WWTP is extended aeration (i.e., modified activated-sludge) facility with a design capacity of 80,000 gpd ADF

6

8. Identify water quality problems, consider alternative control measures, and recommend solutions for implementation.

Both groundwater and surface water in the area have been impacted by historic mining. The town is discharging treated effluent to Asarco for use in its industrial processes, thereby minimizing any chance of it reaching the aquifer or surface waters

19-21

9. If private WWT utilities with certificated areas are within the proposed regional service area, define who (municipal or private utility) will serve which areas, and when service will be available in the designated areas.

A small portion of the Asarco Hayden Operations flows will not be conveyed to the new WWTP but rather will be treated with a new, small wastewater treatment plant that will be installed by Asarco on its property. This small package plant will have a design capacity of approximately 6,800 gallons per day and treat domestic wastewater and shower water from several facilities including a shop, warehouse, administration building and change house.

7-9

REQUIREMENT



ADDRESSED ON PAGE:

10. Describe method of effluent disposal and reuse sites (if appropriate).

The new WWTP will discharge treated effluent into a conveyance line for use in the Asarco Hayden Operations industrial processing. There are no current plans to reuse the effluent from the WWTP within the community.

16-17

11. If Sanitary Districts are within a proposed planning or service area, describe who serves the Sanitary Districts and when.

N/A N/A

12. Describe ownership of land proposed for plant sites and reuse areas.

Asarco has conveyed ownership of the WWTP site to the Town as well as necessary easements and/or rights-of-way to the site and any infrastructure located on or crossing Asarco lands

8

13. Address time frames in the development of the treatment works.

The WWTP will be built in one phase. Construction is anticipated to begin in spring, 2011

18

14. Address financial constraints in the development of the treatment works.

Income level, unemployment, population

25

REQUIREMENT



ADDRESSED ON PAGE:

15. Describe how discharges will comply with EPA municipal and industrial stormwater discharge regulations.4

The facility flows are less than the MSGP threshold for required coverage, however, there will be no industrial discharges into the WWTP

23

16. Describe how open areas & recreational opportunities will result from improved water quality and how those will be used.

N/A 20-21

17. Describe potential use of lands associated with treatment works and increased access to water-based recreation, if applicable.

The land for the WWTP will be dedicated to that use. The products of the WWTP will have no impact on water-based or other recreational opportunities

21

REGULATIONS

18. Describe types of permits needed, including AZPDES, APP and reuse.

Individual APP; Type 4.01 APP General Permit (for collection system); AZPDES Construction General Permit

22-23

19. Describe restrictions on AZPDES permits, if needed, for discharge and sludge disposal.

N/A 23

20. Provide documentation of communication with ADEQ Permitting Section 30 to 60 days prior to public hearing regarding the need for specific permits.

Permit applications have been submitted to ADEQ by both the Town and Asarco and are either approved or in process.

22-23

4 FWPCA § 402; 33 U.S.C. § 1342(p)

REQUIREMENT



ADDRESSED ON PAGE:

21. Describe pretreatment requirements and method of adherence to requirements.5 [40 CFR Part 403 requires a publicly owned treatment works (POTW) with a total design flow greater than 5 mgd and that receive industrial user discharges must establish a pretreatment program.]

This WWTP will treat municipal wastewater, does not include flows from any industrial facility and the design capacity is only 80,000 gpd, therefore no pretreatment program is required

3, 12, 15

22. Identify, if appropriate, specific pollutants that will be produced from excavations and procedures that will protect ground and surface water quality.6

Appropriate construction best management practices will be implemented during construction which will protect both surface and groundwater

20, 23

23. Describe alternatives and recommendation in the disposition of sludge generated.7

Sludge will be dried in two proposed sludge drying beds. The plant will generate approximately 22 dry tons of sludge annually, which will be disposed of at an approved facility or be used for mine reclamation

4, 15-16, 23

24. Define any nonpoint issues related to the proposed facility and outline procedures to control them.

No nonpoint related issues are anticipated

20, 23

25. Describe process to handle all mining runoff, orphan sites and underground pollutants, if applicable.

N/A N/A

5 FWPCA § 208; 33 U.S.C. § 1288(b)(2)(C)(iii) 6 FWPCA §§ 208, 304; 33 U.S.C. §§ 1288(b)(2)(K), 1314, Information and guidelines 7 FWPCA § 405; 33 U.S.C. § 1345, Disposal or use of sewage sludge

REQUIREMENT



ADDRESSED ON PAGE:

26. If mining related, define where collection of pollutants has occurred, and what procedures are going to be initiated to contain contaminated areas.

N/A N/A

27. If mining related, define what specialized procedures will be initiated for orphan sites, if applicable.

N/A N/A

CONSTRUCTION

28. Define construction priorities and time schedules for initiation and completion.

The WWTP will be built in a single phase. Construction will likely commence in spring 2011 and is anticipated to be complete in the fall of 2011

18

29. Identify agencies that will construct, operate and maintain the facilities and otherwise carry out the plan.

Once built, the WWTP and collection will be owned and operated by the Town of Hayden. Asarco, Inc. will also install a small package WWTP on lands owned by Asarco to treat some remaining non-industrial flows from its operations

25

30. Identify construction activity-related sources of pollution and set forth procedures and methods to control, to the extent feasible, such sources.

Anticipated pollutants as a result of construction may include dust, construction related solid waste and inert materials. Mitigation will be handled through BMPs outlined in the SWPPP

18, 23

REQUIREMENT



ADDRESSED ON PAGE:

FINANCING AND OTHER MEASURES NECESSARY TO CARRY OUT THE PLAN

31. If plan proposes to take over certificated private utility, describe how, when and financing will be managed.

N/A

N/A

32. Describe any significant measures necessary to carry out the plan, e.g., institutional, financial, economic, etc.

Adequate funding 25

33. Describe proposed method(s) of community financing.

Grants, loans and user fees 25

34. Provide financial information to assure DMA has financial capability to operate and maintain wastewater system over its useful life.

A letter signed by the Town’s mayor is provided in Appendix 3

25, Appendix 3

35. Provide a timeline outlining period of time necessary for carrying out plan implementation.

The WWTP should be operational in the fall of 2011 after system startup

18, 25

36. Provide financial information indicating the method and measures necessary to achieve project financing.

The project will be financed by USDA Rural Development funds. The Town will fund operation and maintenance of the facility through use fees, etc.

25

IMPLEMENTABILITY

37. Describe impacts on existing wastewater facilities, e.g., sanitary district, infrastructure/facilities and certificated areas.

There are currently no existing wastewater facilities, just a collection system for untreated sewage which will require significant rehabilitation

3-4

REQUIREMENT



ADDRESSED ON PAGE:

38. Describe how and when existing package plants will be connected to a regional system.

There are no existing package plants. The concept of a regional system with neighboring communities will be explored over the 20-year planning horizon for this system

20-21

39. Describe the impact on communities and businesses affected by the plan.

The WWTP will provide the only means of wastewater treatment for the Town of Hayden. The impact to the community will be in the form of higher user fees

20-21

40. If a municipal wastewater (WWT) system is proposed, describe how WWT service will be provided until the municipal system is completed; i.e., will package plants and septic systems be allowed, and if so, under what circumstances? (Interim services.)

Currently untreated sewage is collected from the entire town and disposed on tailings piles. This practice will continue until the WWTP is operational. ASARCO’s APP permit (P-100507) contains a requirement to submit a plan by August, 2010 to cease the disposal of untreated sewage

2-4

PUBLIC PARTICIPATION

41. Submit copy of mailing list used to notify the public of the public hearing on the 208 amendment.8

To be completed by CAAG

42. List location where documents are available for review at least 30 days before public hearing.


8 40 CFR § 25.5, Public hearings

REQUIREMENT



ADDRESSED ON PAGE:

43. Submit copy of the public notice of the public hearing as well as an official affidavit of publication from the area newspaper. Clearly show the announcement appeared in the newspaper at least 45 days before the hearing.


44. Submit affidavit of publication for official newspaper publication.


45. Submit responsiveness summary for public hearing.


APPENDIX 4 – REFERENCES

Arizona Administrative Code (A.A.C.). Title 18, Environmental Quality, Chapter 9: “Water Pollution Control” Articles 1 and 2: Individual Aquifer Protection Permits A.A.C. Title 18, Environmental Quality, Chapter 2: “Air Pollution Control” A.A.C. Title 18, Environmental Quality, Chapter 9, Article 7: “Direct Use of Reclaimed Water.” A.A.C. Title 18, Environmental Quality, Chapter 9, Article 10: “Arizona Pollution Discharge Elimination System – Disposal, Use, and Transportation of Biosolids.” A.A.C. Title 18, Environmental Quality, Chapter 11, Article 4: “Aquifer Water Quality Standards” Arizona Department of Environmental Quality (ADEQ), “Ambient Groundwater Quality of the Lower San Pedro Basin,” July, 2002 ADEQ, “The Hayden PM10 State Implementation Plan,” Oct 19, 1989. ADEQ, “Hayden Sulfur Dioxide Nonattainment Area State Implementation and Maintenance Plan,” June, 2002 ADEQ, Aquifer Protection Permit (APP) No. P-100507, June 4, 2009 Arizona Revised Statutes (A.R.S) § 11-830, “Restriction on regulation; exceptions; aggregate mining regulation; definitions” Burgess & Niple, Inc., “Preliminary Engineering Report for Wastewater Treatment System Improvements, Town of Hayden, Arizona,” June 2009. Burgess & Niple, Inc., “Basis of Design Report, Wastewater Treatment System Improvements, Town of Hayden, Arizona,” November, 2010. Code of Federal Regulations (CFR) 40 CFR Part 403, “General pretreatment regulations for existing and new sources of pollution”, July 1, 2008. PMC, Hayden Arizona Wastewater Treatment Project-Draft Environmental Assessment, June 30, 2009, Population Technical Advisory Committee (POPTAC), Population Estimates for the Town of Hayden, 2009

http://www.access.gpo.gov/nara/cfr/waisidx_08/40cfr403_08.html

http://www.access.gpo.gov/nara/cfr/waisidx_08/40cfr403_08.html

United States Census Bureau, Census 2000 Fact Sheet for Hayden

town of hayden wastewater treatment …...current asarco mine, kennecott copper corporation, in...

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