ecological investigation workplan and sampling plan …
TRANSCRIPT
V-0U/
ECOLOGICAL INVESTIGATIONWORKPLAN AND SAMPLING PLAN
FOR FIELDS BROOKFLOODPLAINS AND WETLANDS
Prepared for:
de Maximis, Inc.Civic Center Plaza, Suite 104
33300 Five Mile RoadLivonia, MI 48154
Prepared by:
EA Mid-Atlantic Regional OperationsEA Engineering, Science, and Technology, Inc.
15 Loveton CircleSparks, MD 21152
DRAFTSeptember 1993
EA 12233.05
TABLE OF CONTENTSPAGE
LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
ACRONYM AND ABBREVIATION LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . ; . . .V : . . . . . . . . . . 1-1
1.1 FLOODPLAIN AND WETLANDS IN THE FIELDS BROOK WATERSHED . . 1-2
1.2 Study objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
1.3 Planning documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
2.0 SITE BACKGROUND AND SETTING . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1 Geology and Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.2 Biological Communities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
3.0 INITIAL EVALUATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1 Contaminant characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.2 Potential exposure pathways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.2.1 Surface Water as a Potential Exposure Route . . . . . . . . . . . . . . . . . . . 3-33.2.2 Contaminated Soils and Sediments as a Potential Exposure Route . . . . . . 3-43.2.3 Ecological Exposure via the Food Web . . . . . . . . . . . . . . . . . . . . . . 3-4
3.3 Study activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
4.0 ECOLOGICAL INVESTIGATION WORK PLAN RATIONALE . . . . . . . . . . 4-1
4.1 Data quality/quantity needs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.1.1 Soil and Sediment Data Requirements . . . . . . . . . . . . . . . . . . . . . . . 4-24.1.1.1 ARARs for Soil and Sediment . . . . . . . . . . . . . . . . . . . . . . . . 4-44.1.1.2 Critical Samples for Soil and Sediment Analysis . . . . . . . . . . . . . 4-5
TABLE OF CONTENTS(Continued)
EAGE
4.1.2 Surface Water Sampling Data Requirements . . . . . . . . . . . . . . . . . . . 4-54.1.2.1 ARARs for Surface Water . . . . . . . . . . . . . . . . . . . . . . . 4-64.1.2.2 Critical Samples for Surface Water Analysis . . . . . . . . . . . . . . . 4-6
4.1.3 Biological Tissue Sampling Data Requiremt . . . . . . . . . . . . . . . . . 4-74.1.3.1 ARARs for Tissue Samples . . . . . . . . . . . . . . . . . . . . . . . . . . 4-94.1.3.2 Critical Samples for Tissue . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
4.2 SITE SAMPLING WORK PLAN DESIGN AND RATIONALE . . . . . . . . 4-10
4.2.1 Stage I Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-114.2.1.1 Human Use Characterization . . . . . . . . . . . . . . . . . . . . . . . . 4-114.2.1.2 Wetlands Ecosystem Characterization . . . . . . . . . . . . . . . . . . 4-134.2.1.3 Sediment Transport Screening Analysis . . . . . . . . . . . . . . . . . 4-14
4.2.2 Stage II Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-154.2.2.1 Review of Existing Data . . . . . . . . . . . . . . . . . . . . . . . . . . 4-164.2.2.2 Preliminary Site Characterization . . . . . . . . . . . . . . . . . . . . . 4-16
4.2.3 Stage III Activities . . . . . . . . . . . . . " . . . . . . . . . . . . . . . . . . . . . 4-204.2.3.1 Acid Volatile Sulfide / Simultaneously Extracted Metals . . . . . . . 4-21
5.0 ECOLOGICAL INVESTIGATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1 STAGE I INVESTIGATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
5.1.1 Human Use Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-35.1.2 Wetlands Ecosystem Characterization . . . . . . . . . . . . . . . . . . . . . . . 5-35.1.3 Sediment Transport Screening Analysis . . . . . . . . . . . . . . . . . . . . . . 5-4
5.2 STAGE II INVESTIGATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.3 STAGE III INVESTIGATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.3.1 Focused Field Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-105.3.1.1 Sediment and Soil Analyses . . . . . . . . . . . . . . . . . . . . . . . . 5-105.3.1.2 Surface Water Analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-115.3.1.3 Biological Tissue Contaminant Analyses . . . . . . . . . . . . . . . . . 5-11
11
TABLE OF CONTENTS(Continued)
EASE
5.3.1.4 Benthic Community Structure Analysis . . . . . . . . . . . . . . . . . . 5-205.3.1.5 Wetland Habitat Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . 5-205.3.1.6 Toxicity Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-225.fe'.? Pitfall Traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
5.3.2 Baseline Ecological Risk Assessment . . . . . . . . . . . . . . . . . . . . . . . 5-245.3.2.1 Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-255.3.2.2 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-255.3.2.3 Site and Study Area Description . . . . . . . . . . . . . . . . . . . . . . 5-255.3.2.4 Contaminants of Concern . . . . . . . . . . . . . . . . . . . . . . . . . . 5-265.3.2.5 Exposure Characterization . . . . . . . . . . . . . . . . . . . . . . . . . 5-265.3.2.6 Risk Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-275.3.2.7 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-275.3.2.8 Conclusions and Recommendations . . . . . . . . . . . . . . . . . . . . 5-285.3.2.9 Exposure Evaluation Model . . . . . . . . . . . . . . . . . . . . . . . . 5-285.3.2.10 Toxicity Reference Values (TRVs) . . . . . . . . . . . . . . . . . . . . 5-39
5.4 DATA MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-305.4.1 Document Control and Inventory . . . . . . . . . . . . . . . . . . . . . . . . . 5-30
6.0 SAMPLE HANDLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.1 SAMPLE NUMBERING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.2 ANALYTICAL PARAMETERS AND METHODS . . . . . . . . . . . . . . . . . 6-2
6.3 SAMPLING PRINCIPLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
6.3.1 Sampling Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-36.3.1.1 Water Samplers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-36.3.1.2 Excavation Equipment and Soil Samplers . . . . . . . . . . . . . . . . . 6-36.3.1.3 Biota Samplers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
6.3.2 Sample Container Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-46.3.3 Reagents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-56.3.4 Sample Preservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-56.3.5 Collection of the Sample . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
in
TABLE OF CONTENTS(Continued)
PAGE
6.4 SAMPLE CUSTODY AND SHIPMENT . . . . . . . . . . . . . . . . . . . . . . . . 6-6
6.5 SAMPLE TRACKING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
7.0 PROJECT SCHEDULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
8.0 PROJECT MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
8.1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
8.2 Program Manager Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-18.3 Project Manager Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
8.4 Quality Assurance Officer Responsibilities . . . . . . . . . . . . . . . . . . . . . . . 8-2
8.5 Health and Safety Officer Responsibilities . . . . . . . . . . . . . . . . . . . . . . . 8-2
8.6 Field Activities Manager Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . 8-3
9.0 REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
ADDENDA
A - Discussion of Fields Brook PRP organization approach to wetlands and floodplains
IV
LIST OF FIGURES
1-1 Fields Brook vicinity map.
1-2 Fields Brook site map.
3-1 Initial conceptual site model, fields brook floodplain.
3-2 Principle routes of contaminant interaction on Fields Brook floodplain.
4-1 Conceptual approach Phase II Fields Brook wetlands assessment.
4-2 Data quality objective (DQO) summary form for soil/sediment samples for toxicitytesting.
4-3 Data quality objective (DQO) summary form for acid volatile sulfide-simultaneouslyextracted metal samples.
4-4 Data quality objective (DQO) summary form for water samples.
4-5 Preliminary conceptual food-web model.
4-6 Data quality objective (DQO) summary form' for biological samples.
5-1 Proposed biota sampling locations along the mainstem of Fields Brook.
5-2 Generalized approach to Fields Brook floodplain biota investigation.
6-1 Sample chain-of-custody record.
LIST OF TABLES
2-1 Mammal species potentially present (based on range of habitat) in Fields Brookwatershed.
2-2 Reptile and amphibian species potentially present (based on range of habitat) in FieldsBrook watershed.
2-3 Summer, winter, and year round resident bird species potentially present (based onrange of habitat) in Fields Brook watershed; and species observed during sitereconnaissance in Spring 1992.
4-1 Previous soil/sediment analytical data for Fields Brook floodplain (WCC 1992).
4-2 Physicochemical parameters to be analyzed in Phase III of Fields Brook floodplainbaseline risk assessment.
5-1 Analytes, CAS numbers, and analytical methods.
5-2 Sample size requirements for tissue analytical methods.
VI
ACRONYM AND ABBREVIATION LIST
AET Apparent Effects ThresholdARARs Applicable or Relevant and Appropriate RequirementsAVS Acid Volatile SulfideBAF Bioaccumulation FactorsCERCLA Comprehensive Environmental kesponse, Compensation, and Liability ActCOC Contaminant of ConcernFS Feasibility StudyDQO Data Quality ObjectiveEIWP Ecological Investigation WorkplanEP Equilibrium PartitioningER-L Effects Range-LowER-M Effects Range-MedianHEP Habitat Evaluation ProcedureHSI Habitat Suitability IndexNEPA National Environmental Policy ActNOAEL No Observed Adverse Effect LevelNPL National Priorities ListQAPP Quality Assurance Project PlanRl Remedial InvestigationROC Receptor of ConcernROD Record of DecisionSARA Superfund Amendments and Reauthorization ActSAV Submerged Aquatic VegetationSEM Simultaneously Extracted MetalsSOP Standard Operating ProceduresSQDI Sediment Quantification Design InvestigationSSP Site Health and Safety PlanTAL Target Analyte List
vii
TBC To Be ConsideredTCL Target Compound ListTQ Toxic QuotientTRY Toxicity Reference ValueVGA Volatile Organics AnalysisWET Wetlands Eva '^n TechniqueWQC Water Quality Criteria
Vlll
1. INTRODUCTION
The Fields Brook Site is located in the City of Ashtabula in northeastern Ohio. Theupstream reaches of the Brook drain through an industrial area which had multiple sourcesthat contributed both organic and metal contaminants to the site. Previous investigations ofthe site have found contaminants in sediments, and the site has been listed by the U.S. EPAon the National Priorities List (NPL).
Contamination in Fields Brook channel sediments was addressed in earlier assessments, andsediment cleanup is proceeding under the established Record of Decision (ROD; 1986).Concern has been expressed for potential contamination of soils and sediments in thefloodplain and wetland soils and sediments in the vicinity of Fields Brook. The nature,extent, and implications of potential contamination in these areas have not been addressed ashave those of the streambed. Potential concerns relating to the Fields Brook floodplain andwetlands are:
Potential for floodplain and wetland soil and sediments to act as secondarysources of contaminants to the remediated streambed;
Potential human exposure through recreational and incidental use of thefloodplain and wetlands;
Baseline exposure risk to organisms living in and on the floodplain andwetland;
Risk-of-remedy (potential habitat destruction associated with possible soil orsediment removal operations) and risk of residual contamination under variouspossible remediation scenarios.
1-1
- -— a
To address these concerns, a baseline quantitative ecological risk assessment will beconducted. This assessment will include characterization of potential receptors andidentification of representative species for quantitative evaluation, characterization ofcontaminants of concern, identification of exposure pathways, and risk quantitation. Thiseffort was initiated in April 1992 with a site reconnaissance visit by personnel from the PRPOrganization and regulatory agencies. The assessment will continue as detailed in this WorkPlan (EIWP) and associated supplemental planning documents.
1.1 FLOODPLAIN AND WETLANDS IN THE FIELDS BROOK WATERSHED
The Fields Brook watershed is located in Ashtabula County in northeastern Ohio (Figure 1-I). There are numerous industrial sites in the watershed which have contributed a variety ofcontaminants to Fields Brook and its surrounding floodplain (Figure 1-2). Data on the siteprevious to 1985 are summarized in the final site RI report (CH2MHU1 1985). USEPApromulgated a ROD which addresses remediation of the streambed. The streambedassessment supporting the remedial action includes a number of samples taken in thefloodplain outside the stream channel proper. These samples indicated potentialcontamination in the floodplain, and concern was expressed regarding the nature and extentof contamination in the floodplain, and potential dynamics of the floodplain and wetland soilsand sediments.
Figure 1-2 is a consolidated map illustrating approximate floodplain and wetland boundariesin the Fields Brook watershed. This map reflects current understanding of the watershedstructure including locations of the stream channel, 10- and 100-year floodplains, andwetlands. In addition, the map shows possible source locations in which floodplainsediments are being investigated for potential treatment in the same manner as the streamchannel sediments discussed in the 1986 ROD.
In general, the areas mapped on Figure 1-2 as "floodplain" and "wetland" cannot befunctionally distinguished (Attachment A, "Discussion of Fields Brook PRP Organization
1-2
i MonroeKelloggsvitle | Canter
__ 5 __-''Geneva' . •"
, ,J>4
•) ©fidck ———-
I: Hartsgrova \5
N MontviHe sK* -' JlfldjievilleJ !̂ ™t\
.per Pike •N"^' \ North6Me*opotamit Blooftifietd f
... - • f. i • .M ddlefiald s
10 Miles
N 10 15 Kilometers
Figure 1-1. Fields Brook vicinity map.
SM'l-W-V -TU
CMI
NOTE: Original figure is in color and is identical to the one provided in theprevious draft of this workplan.
Approach"). The ecology, geology, and hydrology of the floodplain and wetland areas aredistinct from those of the stream channel, but are fairly uniform from the streambanks to theupland boundaries. Thus, the areas mapped as "floodplain" in Figure 1-2 cannot bedifferentiated ecologically from those mapped as "wetland". For risk characterization andrisk management decision-making, the most scientifically sound approach is to treat theseareas as a sin/ -mit, with minor exceptions as detailed below.
Certain areas of the floodplain will be treated in the same manner as stream channelsediments discussed in the 1989 Statement of Work, using the same investigatory criterialevels and cleanup criteria. These areas fall into three categories: eroding sediments which,if not controlled, are potential sources of contamination to Fields Brook; highly contaminatedareas which present potentially unacceptable sources of ecological risk; and contaminatedresidential areas which present potentially unacceptable human exposure. Erosional areaswere found during field reconnaissance to be small and localized, and cannot be mappedeffectively on a watershed scale. All three of these categories will be better delineated andtreated in a fashion similar to stream channel sediments. All other areas will be treatedseparately for risk characterization and evaluation of remedial alternatives.
Because the 10- and 100-year floodplain areas cannot be differentiated ecologically from thebasin-wide wetland, the terms "the floodplain" (the physical environment) and "the wetland"(the ecosystem in the floodplain), as used throughout this EIWP, refer to the same portionsof the Fields Brook watershed. The nature of the physical system is such that the floodplainextent likely does not depend on storm events, but on vernal runoff and water tableseasonality. The biotic community present in the wetlands is an expression of these physicalconditions.
1-3
1.2 STUDY OBJECTIVES
The overall objectives of the approach discussed in this Work Plan are:
• To meet the applicable requirements of CERCLA and the NCP forenvironmental assessment at NPL sites; and
• To respond to issues and concerns raised by U.S. EPA and Ohio EPA duringmeetings with the FBPRPO and in comments dated June 1992 to the originalSQDI for the Fields Brook site (although the ecological investigation of thefloodplain/wetlands area is not part of the operable unit addressed by the ^SQDI).
The approach detailed in this EIWP and supporting documents (QAPP and SSP supplements)incorporates the latest available guidance and concepts on ecological risk assessment (U.S.EPA 1989a & b, 1989b, 1992a, 1992b; 1992c, Ohio EPA 1991), and details state-of-the-artanalyses to assess contaminant bioavailability, bioaccumulation, and effects. In keeping withcurrent guidance and the NCP, specific objectives of the study are to:
• Characterize the nature and extent of contamination;w
• Quantify potential contaminant impacts to the biological community and tohuman health; and
• Support development and evaluation of risk management alternatives.
1-4
1.3 PLANNING DOCUMENTS
Planning documents for the Sediment Quantification Design Investigation (SQDI) werepreviously submitted, reviewed, and revised. Although this EIWP does not specificallyaddress the operable unit covered by the SQDI, the floodplains/wetlands areas have beensampled as part of that investigation and these documents are therefore rek. **. to theecological investigation. This EIWP describes a quantitative assessment of the Fields Brookfloodplain and wetlands areas. The EIWP provides the technical foundation for performanceof additional studies to meet the objectives specified in Section 1.2 above. Detaileddiscussions of sampling, analytical, QA/QC, and health and safety procedures are limited inthis EIWP to topics which have not been addressed in the SQDI work plan.
This EIWP describes approaches and activities associated with investigations of bioaccessiblefloodplain soil and sediments, surface water, and biota. The Supplemental Quality AssuranceProject Plan (QAPP) documents QA/QC procedures to meet DQOs associated with samplesand analyses beyond those undertaken in studies associated with SQDI studies. TheSupplemental Site Health and Safety Plan (SSP) provides detailed health and safetyprocedures for additional investigatory activities.
1-5
2. SITE BACKGROUND AND SETTING
2.1 Geology and Soils
The Fields Brook watershed lies wholly within the Eastern Lake Section of the CentralLowland Province, £~"-rtn of Lake Erie and north of the Ashtabula Moraine, a remnant ofWisconsin glaciation. Fields Brook surface drainage is generally from east to west, throughlocal topography ranging from a wide, low-gradient floodplain to steeper, narrow passagesthrough bluffs along the Ashtabula River.
The unconsolidated overburden is glacial till, ranging from 0 to 60 feet thick throughout thewatershed. Underlying bedrock and exposed outcrops are Devonian shales of the Chagrinmember of the Ohio Formation. This material is of low permeability and serves as anaquitard (reducing water movement) or aquiclude (preventing water movement) wherepresent.
Primary natural soil units present in the Fields Brook watershed are Conneaut silt loam andSwanton fine sandy loam. These soils are level, acidic and have high seasonal water tables,as expected from their location in a seasonal floodplain.
A considerable area of the Fields Brook watershed is associated with anthropogenic (manmade) surfaces. These include hardtop parking areas, roads, buildings, weedlots, managedlawns, and second growth shrub and forest stands. Relative areas of these land-use typeswithin the watershed are not presently available, but will be developed qualitatively duringfield activities. In general, the relative area of impervious surface is low, and the streamsideriparian corridor generally supports intact vegetation communities of various kinds.
2-1
2.2 Biological Communities
Biological communities vary throughout the watershed, depending primarily on the degree ofdisturbance at a particular location. Managed turf and bare ground support the mostdepauperate biota, but serve as feeding areas for birds and omnivorous mammals. Suchhabitat:_ ver only a small fraction of the watershed area. More typical are second growthshrub and wooded wetlands, which cover the majority of the watershed. These are highquality, closed canopy, structured systems supporting a typical wetland biota. Small fringingmarshes occur throughout the riparian corridor. Larger marsh areas and some open waterare present in the upper reaches of the watershed. Fish, invertebrates, and submergedaquatic vegetation are present in these areas.
Among key potential receptors will be vertebrate species inhabiting wetland areas of theFields Brook Watershed. Lists of mammal and herptile (reptile and amphibian) taxapotentially present in the Fields Brook watershed based on habitat and range are presented inTables 2-1 and 2-2 respectively. Bird species which are potentially present as seasonal oryear-round residents, are listed in Table 2-3. These lists will be refined by observations asstudies progress.
2-2
Table 2-1. Mammal species potentially present (based on range and habitat) in Fields BrookWatershed. Common names listed are from Burt and Grossenheider (1980).
Opossum Masked shrewSmoky shrew Least shrewShortail shrew Starnose moleKeen myotis Little brown myotisIndiana myotis , Small-footed myotisSilver-haired bat Eastern pipistrelHoary bat Red batBig brown bat Eastern pipistrel batEvening bat RaccoonLeast weasel Long tail weaselMink River otterStriped skunk . CoyoteRed fox Grey foxWoodchuck Eastern chipmunkEastern grey squirrel Eastern fox squirrelRed squirrel Southern flying squirrelBeaver White-footed mouseDeer mouse Eastern woodratSouthern bog lemming Boreal redback voleMeadow vole Yellownose volePine vole MuskratNorway rat House mouseWoodlands jumping mouse PorcupineSnowshoe hare Eastern cottontailWhitetail deer
Table 2-2. Reptile and Amphibian species potentially present (based on range and habitat)in Fields Brook watershed. Common names listed are as standardized byAmerican Society of Ichthyologists and Herpetologists as used in Conant (1975).
Common snapping turtleStinkpot turtleMidland painted turtleEastern box turtleFive-lined skinkQueen snakeNorthern ribbon snakeEastern hognose snakeNorthern brown snakeNorthern black racerEastern milk snakeHellbenderRed spotted newtJefferson salamanderMarbled salamanderNorthern dusky salamanderNorthern red salamanderRavine salamanderFour-toed salamanderLong-tailed salamanderFowler's toadGray treefrogGreen frogNorthern leopard frogWood frog
Spotted turtleMap turtleBlanding's turtleEastern spiny softshell turtleNorthern water snakeEastern garter snakeNorthern red-bellied snakeNorthern ringneck snakeSmooth green snakeBlack rat snakeEastern massasaugasMudpuppySmall-mouthed salamanderSpotted salamanderSpring salamanderMountain dusky salamanderSlimy salamanderRed-backed salamanderNorthern two-lined salamanderAmerican toadNorthern spring peeperWestern chorus frogBullfrogPickerel frog
Table 2-3. Summer, winter and year round resident bird species potentially present (basedon range and habitat) in Fields Brook watershed. Common names as listed bythe American Ornithologists Unin as used in National Geographic Society(1983).
Pied-billed grebeDouble crested cormorantI-east bitternAmerican bitternBlack-crowned night heronYellow-crowned night heronGreen-backed heronCattle egretGreat blue heronCanada gooseMallardAmerican black duckGad wallGreen wing tealAmerican WigeonNorthern PintailBlue-winged tealRuddy duckWood duckCanvasbackRedheadRingnecked duckCommon merganserHooded merganserKing railVirginia railSoraCommon moorhenAmerican cootKilldeerSpotted sandpiperWilson's phalaropeCommon snipeAmerican woodcockUpland sandpiper
Summer
xxX
X
X
X
X
X
YearRound Winter
Ring billed gullHerring gullCommon ternBlack ternTurkey vultureNorthern harrierSharp-shinned hawkCooper's hawkNorthern goshawkRed-shouldered hawkBroad-winged hawkRed-tailed hawkRough-legged hawkOspreyAmerican kestrelMerlinRuffed grouseNorthern bobwhiteRing-necked pheasantWild turkeyRock doveMourning doveYellow-billed cuckooBlack-billed cuckooCommon barn owlShort-eared owlLong-eared owlGreat horned owlBarred owlEastern screech owlNorthern saw-whet owlWhip-poor-willCommon nighhawkChimney swiftRuby-throated hummingbirdBelted kingfisherRed-bellied woodpeckerNorthern flickerRed-headed woodpeckerYellow-bellied sapsuckerDowny woodpeckerHairy woodpecker
Table 2-3 Continued ~Year
Summer Roundx
Winter
-- Table 2-3 Continued «
YearSummer Round Winter
Pileated woodpecker xEastern kingbird xGreat crested flycatcher xOlive-sided flycatcher xEastern wood-pewee xEastern phoebe xLeast flycatcher xAcadian flycatcher xWillow flycatcher xAlder flycatcher xHorned lark xTree swallow xPurple martin xBank swallow xNorthern rough winged swallow xCliff swallow xBarn swallow xBlue jay xAmerican crow xTurfted titmouse xBlack-capped chickadee xBrown creeper xWhite-breasted nut hatch xRed-breasted nuthatch xHouse wren xWinter wren xCarolina wren xMarsh wren xSedge wren xGolden-crowned kinglet xBlue-gray gnatcatcher xEastern bluebird xWood thrush xVeery xSwainsons thrush xHermit thrush xAmerican robin xLoggerhead shrike xNorthern shrike xGray catbird xNorthern mockingbord xBrown thrasher x
-- Table 2-3 Continued -
YearSummer Round Winter
Cedar waxwing xEuropean starling xWhite-eyed viveo xYellow-throated viveo xSolitary viveo xRed-eyed viveo xWarbling viveo xProthonotary warbler xBlue-winged warbler xGolden winged warbler xNashville Warbler xNorthern Parula xBlack and white warbler xBlack throated blue warbler xCerulean warbler xBlackburnian warbler xChestnut sided warbler xMangolia warbler xYellow-rumped warbler xBlack-throated green warbler xPrairie warbler xPine warbler xYellow warbler xMourning warbler xKentucky warbler xCanada warbler xHooded warbler xWorm eating warbler . xOvenbird xLouisiana waterthrush xNorthern waterthrush xCommon yellowthroat xYellow-breasted chat xAmerican redstart xRose-breasted grosbeak xNorthern cardinal xIndigo bunting xRufous sided Towhee xGrasshopper sparrow xHenslows sparrow xVesper sparrow xSavannah sparrow x
-- Table 2-3 Continued --
YearSummer Round Winter
Song sparrow xAmerican tree sparrow xField sparrow xChipping sparrow xDark-eyed junco xWhite throated sparrow xWhite crowned sparrow xSwamp sparrow xBobolink xEastern meadowlark xRed-winged blackbird xRusty blackbird xBrown-headed cowbird xCommon grackle xOrchard oriole xNorthern oriole xScarlet tanager xHouse sparrow xPine siskin • xAmerican goldfinch xRed crossbill xPurple finch xHouse finch xEvening grosbeak x
3. INITIAL EVALUATION
3.1 CONTAMINANT CHARACTERIZATION
While a substantial effort has been made to characterize contaminants associated with theFields Brook CERCLA site, most of the sampling effort to date has been of contamination inthe streambed rather than of the floodplain. Existing information on the nature and extent offloodplain contamination includes 20 floodplain soil and sediment samples taken as part ofthe Phase I SQDI (WCC 1991). These results provide useful information concerning thenature of soil and sediment contamination in the floodplain of Fields Brook.
Indicator compounds of concern observed during Phase I of the SQDI included metals,semivolatile and volatile organic compounds, as well as pesticides and PCBs (WCC 1992),Specific compounds detected included:
Metals: arsenic, cadmium, copper, lead, mercury, selenium, thallium
Volatile Organics: chloroform, 1,1-dichIoroethylene, 1,1,2,2,-tetrachloroethane,1,1,2-trichloroethane, tetrachloroethylene, trichloroethylene,vinyl chloride
Semivolatile Organics: benzo(a)pyrene, hexachlorobenzene, hexachlorobutadiene,hexachloroethane
Pesticides/PCBs: a-hexachlorocyclohexane (BHC), 7-hexachlorocyclohexane(lindane), heptachlor, Aroclor 1242, 1254, 1260.
Of this list of detected contaminants, arsenic, mercury, hexachlorobenzene, benzo(a)pyrene,and PCB were the most common. Most of these contaminants were detected in at least 1 ofthe 20 surface increment (0-6 inches) floodplain samples taken during Phase I of the SQDI.
3-1
A data summary for these floodplain samples is provided in Table 4-1. These data show thatmost of the volatile and semivolatile organic chemicals are observed in the vicinity of Reach5-2. Average concentrations of these contaminants reported in the draft SQDI report may beartificially inflated due to the method of calculating the arithmetic averages in Table 4-1(non-detects were not included in the calculation). No clear pattern emerges from evaluationof metals concentration data.
Further characterization of the nature, extent and distribution of contaminants in thefloodplain is a major focus of this EIWP.
3.2 POTENTIAL EXPOSURE PATHWAYS
Primary concerns for the environment associated with contamination in the Fields Brookfloodplain are for potential toxicity to ecological receptors and for potential direct andfood-web-based exposure to biota. Because of these concerns, and based on existing data,the following exposure pathways are of potential ecological or human health concern:
• Exposure to dissolved and sediment-bound contaminants in the surface watercolumn of ponded areas in the floodplain;
• Exposure to contaminated soils/sediment; and
• Food-web exposure.
Figure 3-1 illustrates a conceptual model of potential exposure pathways in the Fields Brookfloodplain. Primary sources and release mechanisms of contaminants to Fields Brook havebeen identified and controlled. For this reason, secondary sources of contaminants (soil,sediment, and biota) which could serve to recontaminate Fields Brook are the primaryconcern of this EIWP.
3-2
PRIMARYSOURCES
PRIMARYRELEASEMECHAMSM
SECONDARYSOURCES
SECONDARYRELEASEMECHAMSM
PATHWAY EXPOSUREROUTE
BIOLOGICALRECEPTORS
TwrartM Aqutffe
Owrtow ———— fc*. !£££±L
1
tng~i*on
Mutation
Dwmtfcontact
•
•
•
•
Figure 3-1. Initial Conceptual Site Model, Fields Brook Floodplain
The principle storage compartments for contaminants in the Fields Brook floodplainecosystem are: 1) abiotic (soil, sediment, and surface water), and 2) biotic (producers,consumers, and predators). The general interrelation of these compartments in the FieldsBrook floodplain and wetland are shown in Figure 3-2.
This EIWP is designed as a series of staged k '^ng efforts, each of which will focus onkey components of the environmental compartments described above. Each of these stageswill provide information necessary for evaluation of directly measured exposure and tissueconcentrations, and will guide refinement of subsequent stages to concentrate on datadeficiencies. In addition, this approach will allow delineation of the relationship betweentissue concentrations and exposure concentrations (bioaccumulation factors (BAFs); ratio of ^tissue concentration to exposure concentration) which will serve as input and "reality check"for modeling efforts. This analysis will support comparison of direct exposure tocontaminants (large arrow in Figure 3-2) to toxic thresholds (establishing baseline risks), aswell as providing an estimate of the potential for bioaccumulation of contaminants in the foodweb (extrapolation to unsampled areas or compartments; small arrows in Figure 3-2). Thisapproach is comprehensive in that potential risks associated with contaminants which maybioaccumulate (i.e., be taken up in tissue) but which do not generally biomagnify (increase intissue concentration with trophic level) such as volatile organics, most metals,benzo(a)pyrene, etc., as well as contaminants which can biomagnify (e.g., mercury whichbiomagnifies in the organic form, Eisner 1987), PCBs, hexachlorobenzene, pesticides can beassessed with the same technique.
3.2.1 Surface Water as a Potential Exposure Route
The only extensive surface water habitats within the floodplain are ponded areas behindbeaver dams in the upper watershed (Reach 8-2). No known samples have been taken of thiswater, and the proposed sampling is intended to determine if there are contaminants of
3-3
Media
Floodplain Soil
Sediment
Surface Water
Biota
Producers
Consumers
Predators
Figure 3-2. Principle routes of contaminantInteraction on Fields Brook floodplain
concern present in this area, and to support quantitative analysis of potential exposure and ofthe effects on biotic and human receptors.
3.2.2 Contaminated Soils/Sediments as a Potential Exposure Route
Most potential contaminants of concern are likely associated with soils and sediments of thefloodplain. With the exception of volatile organics, all of the contaminants listed in Section3.1 are hydrophobic (low water solubility; generally very soluble in organic materials) andpreferentially sorb (absorb and adsorb) on soil and/or sediment matrices. Direct contact andfood-web uptake are potential exposure routes for biota to soil and sediment boundcontamination. Direct contact exposure is difficult or impossible to assess directly given thepresent status of ecological science because not all of the involved mechanisms ofcontaminant transport are measurable or currently understood. Because of this lack of abilityto account for all transport mechanisms, it is necessary to use the organisms themselves todescribe the summation of all of the controlling processes. By directly measuringcontaminant concentrations in biotic tissue and relating these concentrations to those found inenvironmental media (soils and sediments), all exposure routes and mechanisms are implicitlyassessed.
3.2.3 Ecological Exposure via the Food Web
One of the principle concerns for contaminant movement in the Fields Brook floodplain isaccumulation of these contaminants in upper levels of the food web. This EIWP describesprocedures necessary to provide information sufficient to define potential movement ofcontaminants in the Fields Brook floodplain food web. In addition, these procedures willaddress the nature and extent of contamination, quantify contaminant risks to potentiallyaffected native species, and project future behavior of contaminants in various environmentalmedia. Since trophic transfer of contaminants (movement within the food web) is a principleconcern, a substantial effort will be devoted to characterizing and modeling the floodplain
food web.
3-4
3.3 STUDY ACTIVITIES
The general objectives of the Phase II Fields Brook floodplain study are to characterize thenature and extent of risks associated with site contamination. The overall objective of thisstudy is to supplement existing investigatory work to support quantitation of site-related risks.A staged investigation approach is proposed to assure the greatest flexibility to focus thtv^investigation on the contaminants and receptors of greatest concern. Specific tasks to beperformed to meet these objectives include:
• Developing an inventory of environmental receptors present in the floodplain,including key wetland plants and animals, and re-evaluation of the presence ofendangered or threatened species;
• Supplementing the existing wetland delineation of Fields Brook floodplain byidentifying and mapping vegetation communities present in the riparian zone(by ground observation and hand-mapping) and calculating relative spatial arearepresented by each community type (by digitization);
• Characterizing the nature and extent of contamination present in floodplainsoil, sediment, surface water, and biota, including screening samples forTarget Compound List and Priority Pollutant metals in biotically active zones;
• Estimating and verifying quantitative risks to the environment due tosite-related contaminants by modeling exposure and toxicity, and measuringtissue concentrations in key receptors.
Based on available information, regulatory guidance, and comments regarding this operableunit, it is anticipated that potential environmental risks will be driven by food webinteractions involving PCBs as the primary bioaccumulative contaminant as well as the
3-5
potential for toxicity resulting from direct contact (non-food web exposure) to othercontaminants.
J,
3-6
4. ECOLOGICAL INVESTIGATION WORK PLAN RATIONALE
This section addresses the Data Quality Objectives (DQOs) necessary to produce thefloodplain baseline risk assessment. The EIWP rationale is presented to illustrate how fieldinvestigation activities will satisfy data needs.
A three stage data collection approach was to be employed in this investigation (Figure 4-1).The staged approach is generally used to optimize sampling intensity, location, and dataneeds for each of the three stages and to assure the greatest flexibility to focus theinvestigation on contaminants and floodplain areas of greatest concern. Sufficient fieldactivities have been conducted to date to provide information for risk assessment componentsto proceed independently of, and in parallel with, one another. Nevertheless, aggregatingcomponents into Stages still represents the most logical presentation scheme and is retained.Stage I data collection efforts concentrate on basic floodplain characteristics, including humanactivity (presence of deer stands, fishing at the site, proximity of residential housing, etc.)and further wetlands characterization. Sediment transport analysis will be conducted duringStage I to address the issue of mobility of floodplain soil and sediments and potential forsecondary contamination of the streambed.
Stage II will incorporate the products from Stage I and existing data on Fields Brookfloodplain soil and sediments. During this Stage, lists of contaminants of concern (COCs)and receptors of concern (ROCs) will be developed for focussed risk characterization. Thisinformation, along with the sediment transport analysis, will allow development of a site-specific food-web model for assessing ecological risks at the site. The biological samplingprogram will focus on collecting the information for modeling risks to receptors identified tobe of concern. In keeping with available guidance (U.S. EPA 1989a) and prior discussionswith Agency scientific staff, biological sampling efforts will be focused on obtainingsufficient numbers of relatively few representative species, including small mammals, to meetproject DQOs.
4-1
Stage I Stage II Stage III
FalM 992 Human UseCharacterization
Spring/Summer 1993
Wetlands EcosystemCharacterization
Sediment TransportAnalysis
FalM 993
Winter 1993-1994
Analysis ofExisting Data
Focusr Field Studies
Preliminary RiskCharacterization
iBaseline RiskAssessment
Figure 4-1. Conceptual Approach to Phase II Fields Brook Wetlands Assessment.
C
Stage III will concentrate on collection of necessary environmental media samples, and onbiological samples for chemical, ecological, and lexicological characterization. These willinclude earthworm toxicity and bioaccumulation tests, terrestrial soil fauna communityanalysis, and focused investigation of benthic and fish communities within ponded areas ofthe floodplain.
Data collection must be sufficient to allow the following tasks to be performed:
• Bioaccessible Contaminant Characterization - Assess the nature and extent ofcontamination within the biologically active zone of Fields Brook floodplainsoil and sediments;
• Ponded Area Contaminant Characterization - Assess the nature ofcontamination within the ponded area in Reach 8-2;
• Biological Tissue Characterization - Assess the nature and extent ofcontamination in potentially affected biota;
• Toxicity Assessment - Assess the potential for Fields Brook floodplain soil andsediment to cause direct toxicity and bioaccumulate into the food web;
• Risk Assessment - Develop a baseline risk assessment for evaluation of thethreat of the site to ecological receptors.
4.1 DATA QUALITY/QUANTITY NEEDS
The following sections document specific data quality/quantity needs for each environmentalmedium to be sampled during field activities for the Sediment Quantification DesignInvestigation at Fields Brook Site Sediment Operable Unit.
4.1.1 Soil and Sediment Data Requirements
Twenty samples were taken of Fields Brook floodplain soil and sediment during Phase I andwere analyzed for the Target Compounds List (TCL) and Target Analyte List (TAL) for
4-2
organic chemicals and metals respectively (WCC 1992). These analyses, summarized inTable 4-1, show that soil and sediments contain a variety of volatile chemicals such as1,1,2,2-tetrachloroethane and trichloroethylene, semivolatile compounds such as chrysene andhexachlorobenzene, pesticides, PCBs, and metals. Bioaccessible soil and sediments are theupper increments of the soil or sediment column (0 - 0.5 or 0 - 1 foot). The full soil andsediment delineation includes deeper samples, but the focus of the environmental assessmentand this EIWP is on the upper, biotically active portion of the soil and sediment column.
The EA supplement to WCC's QAPP (and associated SOPs) details proposed soil andsediment characterization sampling. This program was designed to reflect currently availableinformation, to support general characterization of the nature and extent of contamination,and to provide information necessary for quantitative environmental assessment. Analyseswill be conducted under ILM02.1 and OLM01.8 CLP SOW protocols. The samplingprogram will provide sufficient coverage for evaluating potential biotic exposure, forquantifying risks, and for conceptualizing risk management alternatives should risks toecological receptors be identified. To maximize the utility of the assessment for quantitativerisk evaluation, the sample locations are somewhat flexible. Should new information beobtained before actual sampling is begun, sampling locations may be adjusted. For example,if particularly high-value areas of wetland habitat, areas of heavy human use, areas whichhave changed ecologically since initial investigations, or areas showing overt signs ofpossible toxicant stress are identified, but are not proposed for sampling under the programdetailed in Appendix B, some samples would be relocated for complete coverage of theidentified areas. It is anticipated that the proportion of samples to be relocated would besmall, and that this may be done in the field, fully documented and justified in field notes,and implemented without submitting additional plans for approval. In addition, if it becomesclear during field investigations that planned activities will not adequately address projectobjectives (e.g., recent flooding observed in Reach 4), supplemental plans will be developed.
Sampling for Acid Volatile Sulfide/Simultaneously Extracted Metals (AVS/SEM; discussed inmore detail in section 4.2.3.1 below) can be conducted on a limited subset of locations. This
4-3
Table 4-1. Previous soil/sediment analytical data for Fields Brook floodplain (WCC 1992)
Compound Class Compound NameVolatiles Gig/Kg) 1,1,2,2-tetracMoroethane
1 ,2-dichloroethylene2-butanoneacetonecarbon tetrachloridechlorobenzenemethylene chloridetetrachloroethylenetoluenetrichloroethylenecarbon disulfidechloroformvinyl chloride
ConcentrationRange
ND - 12,000ND - 21,000
ND-750ND-100ND-190
ND- 11,000ND-450
ND - 70,000ND-15
ND - 12,000ND-8
ND- 1,200ND-260
ArithmaticA veragew
2,3903,6201405741
3,270217
12,6005
3,090NA630157
DetectionRatio5/2011/206/2010/205/207/204/2012/207/2014/20
1/204/202/20
Table 4-1. Continued
Compound Class Compound NameSemivolatiles (/ig/Kg) hexachloroethane
anthracenebenz(a)anthracenebenzo(b)fluoranthenebenzo(k)fluoranthenebis(2-€thylhexyl)phthalaie
chrysenefluoranthenehexachlorobutadienenapthalenephenanthrenepyrene1 ,2,4-trichlorobenzene1 ,2-dichlorobenzene1 ,3-dichlorobenzene1,4-dichlorobenzene2-methylnapthaleneacenapthene
ConcentrationRange
ND - 18,000ND-340
ND- 2,100
ND- 2,200ND - 3,900ND- 1,300ND- 3,600ND - 2,100
ND- 230,000ND-230
ND- 4,200ND - 5,100ND - 1,200ND-400ND-700ND - 530A^A^ </*n/
ND-760ND-180
Arithmatic
Average"NA228654750
1,3101,005857608
31,600183
1,200jO
460227605320637101
DetectionRatio1/203/207/207/204/202/2010/1010/1013/203/2010/209/204/204/20
2/202/203/203/20
Table 4-1. Continued
Compound ClassSemivolatiles Oig/Kg) continued
Pesticides and PCBs (/ig/Kg)
Compound Nameacenapthylenebenzo(a)pyrenebenzo(g,h,i)perylenebutylbenzylphthalatedibenz(a,h)anthracenedibenzofurandiethylphthalatedimethylphthalatefluoreneindeno(l,2,3-c,d)pyrenedi-n-butylphthalate
4,4'-DDE4,4'-DDTdieldrinendrinendrin ketoneendosulfan Iendosulfan II
ConcentrationRange
ND-430ND- 1,600ND- 1,600ND-620ND-390ND-110ND-83ND-280ND-440ND-710ND-340ND-540ND- 120ND-67ND-100
ND-34ND-250ND-430
ArithmaticAverage"
2347 56760NA214
10S70173306344NA49576NA
75NA134
211
DetectionRatio2/205/204/201/202/202/202/203/203/205/201/202/202/201/202/201/202/205/20
Table 4-1. Continued
Compound Class Compound NameConcentration
RangeAr jnaticj eragew
DetectionRatio
Pesticides and PCBs G*g/kg) cont.
Metals
endosulfan sulfatea-chlordane7-chlordaneor-hexachlorocyclohexane5-hexacUorocyclohexane7-bexachlorocyclohexane (iindane)heptachlorheptachlor epoxidehexachlorobenzeneAroclor 1242Aroclor 1248Aroclor 1254Aroclor 1260aluminum (percent)antimony (mg/Kg)arsenic (mg/Kg)barium (mg/Kg)
beryllium (mg/Kg)
ND- 194
ND - 17.5ND-410
ND-190ND-72ND-27
ND- 1,000ND - 15.4
ND-50,000ND- 22,000ND- 240,000
ND- 6,600ND - 9,400
0.93-2.8 (0.7-ND-1.2 (<l-8.8)w
5.8-43.1 (<0.1-73)w
85.7-13,400(HM,500)W
NA128102NANANA
NA19,20013,50046,7002,480NA
1.5 (5.9)w
1.0 (0.76)«22 (7.4)w
2,550 (420)̂
ND-19.4 (<l-7)w 6.1 (0.85)*>
4/201/204/202/201/201/201/201/20
15/203/2012/203/201/20
20/202/2020/2020/20
10/10
Table 4-1. Continued
Compound Class Compound NameConcentration
RangeArithmaticAveragew
DetectionRatio
Metals continued cadmium (mg/Kg)calcium (percent)chromium (mg/Kg)cobalt (mg/Kg)copper (mg/Kg)cyanide (mg/Kg)iron (percent)
lead (mg/Kg)magnesium (percent)manganese (mg/Kg)
mercury (mg/Kg)nickel (mg/Kg)potassium (percent)
selenium (mg/Kg)silver (mg/Kg)sodium (percent)
ND-8.9 (NF)0.13-4.4(0.01-28)"18.2-426 (1-1 ,000)"
ND-22.7(< 0.3-70)"15.9-78.6 (< 1-700)"
ND-0.4(NF)1.47-5.85
(0-01-> 10)"12.8-89.6 (<10-300)<b)
0.19-0.74(0.005-5)"194-1,490
(<2-7,000)"0.093-57.7 (0.01-3.4)"13.6-82.6 (<5-700)"
ND-0.182(0.005-3.7)"
ND-9.6 (< 0.1-3.9)"ND-0.89(NF)
ND-0.13 (<0.05-5)"
3.5 (NF)1.6(0.63)"101 (52)"
13.2 (9.2)"48.6 (22)"0.27 (NF)3.1 (2.5)"
55.4 (17)"
0.37 (0.46)"
710 (640)"
8.57(0.12)"43.5 (18)"0.109(NF)
2.5 (0.45)"0.39 (NF)
0.10(0.78)"
13/2020/20
i
20/2017/2020/202/2020/20
20/2020/2020/20
20/2020/2011/20
7/2010/103/20
Table 4-1. Continued
Compound ClassMetals continued
Compound Namevanadium (mg/Kg)zinc (mg/Kg)
ConcentrationRange
19.9-614 (<7-300)w
70.7-286 (<5-2,900f»
ArithmaticAverage**130(66)»154 (52)«
DetectionRatio2<V2020/20
ND = Not DetectedNA = Not ApplicableNF = None Found(a) = Average of observations above detection limit(b) = For the Eastern United States from Shacklette and Boemgen (1984).
L
is because AVS/SEM parameters are properties of the soil type in general and not of specificcontamination. AVS/SEM will be sampled from continually submerged wetland soils andsediments at locations collocated with proposed biota sampling locations (see Section 5.3.1below).
Data collected from soil and sediment sampling v/m he used to assess the nature and extentof contamination located specifically within the biologically active increment of the soil orsediment column. This information will be utilized directly in assessing and projectingpotential contaminant-related risks.
Since this site is an Operable Unit for an NPL site, analytical detection levels for chemicalanalysis will, at a minimum, meet EPA Level III requirements. This level employs approvedEPA procedures with specified detection limits. The appropriate analytical methods anddetection limits are provided in EA's supplement to WCC's QAPP. DQOs for soil andsediment, and AVS/SEM are shown in Figures 4-2 and 4-3, respectively.
4.1.1.1 ARARs for Soil and Sediment
Section 121 (d) of CERCLA requires that remedial actions at Superfund sites comply withrequirements or standards under Federal or State environmental laws that are "applicable" or"relevant and appropriate" to the hazardous substances, pollutants, or contaminants at a siteor the circumstances of the release. A requirement may be either applicable or relevant andappropriate to a remedial action, but not both. An applicable requirement is one thatspecifically addresses a hazardous substance, pollutant, contaminant, remedial action,location, or other circumstances at a hazardous waste site. Relevant and appropriaterequirements, while not applicable, address problems or situations sufficiently similar tothose encountered at a hazardous waste site so that their use is well suited to the particularsite (55 FR 8666, 8 March 1990).
4-4
1. SITENAME Halda Braofc 8QDI
OhioNUMBER MC3flOOE-220
EPARaolonV
PHASE!
2. MEDIA QW AIR BIO OTHER
3. USE SftoCharao. PRPDatK. RA Monitor. OttwrDaakn
4. OBJECTIVE Samola aoaVaadlmant forpoianttalJoxfojtv,
5. SITE INFORMATIONAna §.fl«a. ml. Dapth To Qroundwatar Laaa than 30 ftQraundMNHar Uaa ngnjSoiTypaa flhala bao f̂tc^ Pffyfjfd byjfrlftSanaHrva naoaplori Btota and raeraattonal fdlraot oontaotl
6. DATA TYPES M*A. Analytical Data
AVS/SEM
B. Prtytteal Data
parmaabHHy hydraulicporoatty haad
panatratton
RBPaurvaywaUnddaHn
C. Biological Data
com. struc.
7. SAMPUNQ
•euro*craboompoafta
non-JntrualvaIrrtrualva
phaaad
8. ANALYTICAL LEVELS IM«....I. «.,-*
LEVEL 1 Raid SoraaningLEVELS RaM AnaryaiaLEVELS Non-CLPLab.LEVEL 4 CLP/RAS-̂ . SOW a/flO OCAP and FAAk SOW 3/flO fQC4<S. QC^C. andLEVELS Non t̂ondard SM SOPt PrtMnttd In Addendum B. Chapter4
9. SAMPUNQ PROCEDURESBackground - 2 o*t •vtnt or ThrM from Mch of two background locattont
PfOOKJlHM
10. QUALITY CONTROL SAMPLES .-*..-.A.HtMColloo«ted«.i 100 % wtth othar chamlstrvFtopticAt* n«.i 10%FMd BlankTrip Blank
B. LaboratoryRaaoant Blank n^f.^^iniin.t CLP ProtocolRaoUcate ,. — .„* d.tnn,.,. CLP ProtooolMatrix Spika n »•»ism>»•>•> CLPProtooolQth*r aa oar CLP Protocol
11. BUDGET REQUIREMENTSBud0«t N/A Sotwdul* Sorino/Summar 1903Staff Sarnp||r>g Ttam
Contraotor EA EnalriaarinaSrta Manaotr __
Prima Contractor Tach EnvironmentalData
Figure 4-2. Data quality objective (DQO) summary form for sou/sediment samples fortoxicity testing.
1. SITENAME Ralda Brook SQtMLOCATION Aahtabula. OhioNUMBER MC3fl09E-220
2. MEDIA SOIL QW
EPAFfcolonV
AIR BtO OTHER
3. USE Site Qunc. Altar. Eval. Eng'gOMlgn
PRPDatar. RA Monitor. Othar
4. OBJECTIVE Aaaaaa Dotantitl ritk of dlvaJant haaw matala In floodolaln to*.
5. SITE INFORMATIONATM 5.6 M. ml. Depth To Groundwatar Laaathan20fLGroundwatar Uaa noneSoBTvpaa Shala faadrook oovarad bv driftSanaWva RaoaptofB Blofr and raoraational (dlrfot contact)
6. DATA TYPESA. Anmtytical Data
PCBInorganic*oyanktoDOlightptrwtrationalkallnttyhardnma
TOXTOGDOCBTXCODBOD
B. Physical Data
p*rm»abilityporoaltygrain «iz»buHcdamlty
hydraulichaadpanatrattontacthardnaat
C. Biological Data
RBP•urvaywatlnddaHn
com. time.
?. SAMPLING METHODanvironmantal•ouroa
graboompoaKa
non4ntruatvaintrualva
8. ANALYTtCAL LEVELS ».J.H.I..«.I«I .̂ ..i... i -*~uLEVEL 1 Raid ScraanlngLEVEL 2 FMd AnarytltLEVEL3 Non-CLPLab.iLEVEL 4 CLP/RAS.-̂ 8OW3/9Q flCAP and FAA>______LEVELS Non-Standard Add volatlla mfflda OJ.S. EPA 10Q1J: SOP Attaehad In Chaotar 4of Addandum B
9. SAMPLING PROCEDURESBackground - 2 par avant or Thraa umplaf from two baokoround locations, ona duotlcata
Procaduraa
10. QUALTTY CONTROL SAMPLESA. RaidCollocatad (•%«> 100 % with othar chamlstrvRaplicatan%«) 10%Raid Blank «% «Trip Blank d^*v«
B. LaboratoryRaaoant Blank M — —I.,*. !-.*•> CLP ProtocolRaolicatan».^.^h.M.«> CLP ProtocolMatrix Soika n»»-»»i.i-̂ .»i CLP ProtooojOthar at oar CLP Protocol
11. BUDGET REQUIREMENTSBudgat N/A Schadula SDrino/Summar 1993Staff Samollno Taam
Contractor EA EnalnaarinaSita Managar _______
Prima Contractor Tach EnvironmantalData
Figure 4-3. Data quality objective (DQO) summary fonn for acid volatile sulfide-simultaneously extracted metal samples.
We will compile and apply ARARs for soil and sediment at the site in the context of the pre-SARA ROD (1986). The Superfund Amendments and Reauthorization Act of 1986, PublicLaw 99-499, Section 122(a) (SARA), provides that, "the requirements of Section 121 ofCERCLA shall not apply to any remedial action for which the Record of Decision wassigned ... before the date of enactment." (Pub. L. 99-499, Section 122(b)). The FieldsBrook ROD was signed on September 30, 1986, prior to the enactment of SARA on October17, 1986. Therefore, ARARs to be compiled will comply with U.S. EPA's unilateral 106Order and the Facility Siting Design Investigation SOW. A preliminary listing of thesepossible ARARs is presented in Tables 2-1 and 2-2 of WCC (1990c).
4.1,1.2 Critical Samples for Soil and sediment Analysis
Critical samples are those samples for which data must be obtained to satisfy the objectivesof the sampling and analysis task. They are as follows:
• Field Duplicate-to be collected one per 20 samples per matrix, to comparerepeatability of laboratory chemical analysis results and sampling procedures;
• Trio Blank-rvolatile organics analysis (VOA) only] to accompany eachshipment of samples (if VOA analysis is part of shipment) for purposes ofdemonstrating the effect of transport on the sample.
• Rinsate Blank-even though dedicated field equipment will be used at eachsampling location, one rinsate blank will be taken in the field to verifydecontamination procedures.
4.1.2 Surface Water Sampling Data Requirements
During SQDI Phase I, no samples of surface water were analyzed in the ponded areas of theFields Brook floodplain. Stage III of this study will include sampling and analysis fororganic chemicals and total and dissolved metals within the ponded area. Table 4-2 contains
4-5
TABLE 4-2 PHYSICOCHEMICAL PARAMETERS TO BE ANALYZED IN PHASE III OF FIELDSBROOK FLOODPLAIN BASELINE RISK ASSESSMENT
Matrix
BIOTA
FLOODPLAINSOIL/SEDIMENT
SURFACEWATER
Analyte
TCL(1)- Volatile Organic Chemicals
TCLw-Basc/Ncutral and Acid Extractable
TCLw-Pesticides
Priority Pollutant Metals(Ag, As, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, Tl, Zn)
Cyanide
Upid Content
TCLW- Volatile Organic Chemicals
TCLw-Base/Neutral and Acid Extractable
TCLw-Pesticides
Priority Pollutant Metals(Ag, As, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, 1% Zn)Cyanide
Total Organic Carbon
Acid Volatile Sulfide-Simultaneous Extracted Metals(Cd, Cu, Ni, Pb, Zn)
TCLw-Volatile Organic Chemicals
TCLM-Base/Neutral and Acid ExtractableTCLw-Pesticides
TAL^-Metals (Dissolved and Total)
Cyanide
Hardness
AlkalinitypH
Temperature
Dissolved Oxygen
Conductivity
Light Penetration
Number ofLocations
1111
r U11
11
11
11
11
1111
11
1111
1
11
11
1
11
111
1
Number ofSamples
72*
72*72*72*
72*5&*
14*
12"
12"
12"
12'
12"
36"
4'
3"
3"
3"
3-
3"
1"
ri"rri"
(a) Target Compound List(b) Target Analyte List
***
Analyzed by EA LaboratoriesAnalyzed in Field
Includes Earthworm Tissuesfor Bioaccumulation Analysis
a list of physicochemical parameters to be measured in surface waters in the field (alkalinity,pH, temperature, dissolved oxygen, conductivity, and light penetration) and for analysisfollowing shipment to the laboratory. Three samples are anticipated for surface water fromthe ponded area. DQOs for surface water analyses are shown in Figure 4-4.
Since surface water quality data will be used in ecolog. -odeling and risk assessment, andsince the site is an NPL operable unit, EPA analytical data Level III will be used at aminimum.
4.1.2.1 ARARs for Surface Water si
Ponded areas and associated riparian vegetation represent potential habitat for wildlife.Receptors of potential concern in these areas include native plant and animal species. Wewill compile and apply ARARs for surface water at the site in the context of the pre-SARAROD (1986). The Superfund Amendments and Reauthorization Act of 1986, Public Law 99-499, Section 122(a) (SARA), provides that, "the requirements of Section 121 of CERCLAshall not apply to any remedial action for which the Record of Decision was signed ... beforethe date of enactment." (Pub. L. 99-499, Section 122(b)). The Fields Brook ROD wassigned on September 30, 1986, prior to the enactment of SARA on October 17, 1986. .Therefore, ARARs to be compiled will comply with U.S. EPA's unilateral 106 Order andthe Facility Siting Design Investigation SOW. A preliminary listing of these possibleARARs is presented in Tables 2-1 and 2-2 of WCC (1990c).
4.1.2.2 Critical Samples for Surface Water Analysis
Critical samples for surface water investigations are similar to those for soil and sedimentsampling. All three of the proposed surface water samples are intended for use to assesspotential impacts on receptors feeding on pond vegetation and fish, as well as to assess
4-6
1.8JTENAME RaMaBroofcSQPI
EPARaoionVffiPHASE!
2. MEDIA SON. QW AJR 8*0 OTHER
3. USE SttaOharao.\
AHar.Eval. Eng'gDaalgn
PRPDalar. RA MonHor. Olhar
4. OBJECTIVE Dotantlal riaJt oi contamlnanta In HaMa Brook oond waAar and oaMbrali a food wab modal.
5. SITE (NFORMATIONAf«« B.a aa. ml. Daptti To Qroundwalar Laaathan2QftQroundwatar Uat nonaSoUTypaa fihala hadrook ODvarad bv driftSanaMiva Raoaptora
6. DATA TYPES i**A, Analytical Data a Phyatoal Data
parmaabiUty hydraulicporoafty haadgrain aba panatratfonbufcdanatty taat
RBPaurvaywaflnddaUn
C. Btotofltoal Data
corn, atruo.
7. SAMPUNQ METHOD ianwonmantaj
gridgraboompoaMa
non-lntriMlvtIrrtnulM
phawd
8. ANALYTICAL LEVELS
LEVEL 1 RaMSoraanlngLEVEL 2 RaM AnaJyala *4LEVELSLEVEL 4LEVELS Non-8tandafd SM SOPt PrM»nted In Addendum B. ChuA* 4
9. SAMPUNQ PROCEDURESBackground • 2 par •vant or Nona (no •oofooriata bachoround
PTOOMUCM
10. QUALITY CONTROL SAMPLESA. RaidCoNooatad »» «i NonaRapl)eatan*«t NonaHaU Blank n*-iOnaTrip Blank n ,̂̂ ,. i fVOAonM
B. LaboratoryRaaoant Blank ti»RapHoataMatrix SpHta
aa par CLP Protoool
»t CLP Protoool- 1 CLPProtoo
11. BUDGET REQUIREMENTSBudgat N/A Schadula Soring/Summaf 1883Staff SamoHna Taam
Contractor EA EnotnaarinaSHaManaaar
Prima Contractor Taoh EnvlronmafrtalData
Figure 4-4. Data quality objective (DQO) summary form for water samples.
potential direct exposure. Analyses will be conducted under 1LM02.1 and OLM01.8 CLPSOW protocols.
4.1.3 Biological Tissue Sampling Data Requirements
As a part of the Phase ! Fields Brook RI, fish samples were taken from two locations inFields Brook and three locations within the Ashtabula River and Harbor (CH2MHU1 1985).Three volatile organic chemicals (1,1,2,2-tetrachlorcethane, tetrachloroethylene, andtrichloroethylene), PCBs, hexachlorobenzene, and five metals (selenium, zinc, mercury,arsenic, copper, silver, and beryllium) were measured in these samples. Chemical analysis ^*of terrestrial organisms and plants, as well as characterization of fish in ponded areas of the—Fields Brook floodplain are proposed for Stage III of this assessment (Table 4-2).
A specific contaminant~octachlorostyrene~has been suggested by U.S. Fish and WildlifeService researchers to be potentially associated with Fields Brook. Consultation with thescientist on this issue revealed by agreement that this compound is unlikely to be drivingecological risks, and that the primary utility of any octachlorostyrene measurements would befor possible site-linkage documentation only. Because enforcement is clearly not an objectiveof this assessmentrand with the agreement of the researcher, octachlorostyrene measurement iis not proposed for this investigation.
Samples to support quantitative risk estimates will be based on measured tissueconcentrations and on food web and bioaccumulation model calculations based on this actualmeasurement data from the Fields Brook site. A preliminary food web is illustrated in ~Figure 4-5. The ecological exposure model will be used to calculate dosages of contaminantsof concern to receptors of concern by modeling uptake via dietary consumption of soils,water, plants, and animals. Calculated dosages will be compared totoxicity reference values(TRVs) to determine potential risk. The model is described in greater detail in Section5.3.2. Model calculations will incorporate information on resources observed or potentially
4-7
LargeHerbivorousMammals
SmallHerbivorousMammals
OmnivorousMammals
Terrestrial Aquatic
Figure 4-5. Preliminary conceptual food-web model. Specific receptors will beselected with the paired comparison technique following Stage Iactivities and pathways will be modified to represent these receptors.
present in the Fields Brook floodplain and food web dynamics of the wetland ecosystem asillustrated in Figure 4-5. Samples will be taken of appropriate species to provide data onpotential bioaccumulation, toxicity, and impacts as needed for modeling. This approachminimizes the number of destructive samples that must be taken from wetlands populations,and maximizes the value of each sample by providing a mechanistic basis for understandingcontaminant dynamics in the ecosystem. In addition, through the development of hazardquotients based on toxicity reference values for endpoints which affect individuals (forexample, survival, escape response, thermotolerance) or populations (for example,reproductive rate, propagule production), this information will be used to quantitativelyassess risk to individuals of representative receptor species and qualitatively assess potentialpopulation risks associated with exposure. Receptor species which are the focus of the studyinclude primarily conspicuous and reasonably accessible vertebrates and large invertebrates.To assess risk to these receptors, data will be acquired on tissue body burdens throughout thefood web, giving a complete picture of potential ecological risks.
Assessment endpoints in general are properties of the ecosystem, including in this case ahigh-quality, high-value wetland and its component organisms. While "ecosystem integrity"is a difficult concept to define, the structure and function of a system in the absence ofadverse contaminant effects is a desirable goal which can be defined by the relative "health"of component species populations. Thus, for this risk evaluation, "assessment endpoints" arekey species as characterized by the receptors of concern (ROC) identification process detailedin Chapter 5 of this Work Plan. "Measurement endpoints" are those species and individualsof ROC taxa and/or surrogates which are amenable to and are actually sampled for body-burden analysis. One of the advantages of coupling the site data to a food web model toproject risk effects is that assessment endpoints can be evaluated through data gathered onmeasurement endpoints.
The fundamental basis of the ecological assessment for Fields Brook is measured tissue andenvironmental media concentrations of contaminants. The principal tool to support riskprojections for possible remediation decision-making is a food web model parameterized
4-8
from measured data which allows exploration of the potential of possible exposure-controlscenarios to reduce exposure. Such a model will be based on the food web illustrated inFigure 4-5 and is described more fully, with assumptions, in Chapter 5 of this Work Plan.Data to be collected to support each component of the ecological risk assessment andprocedures for sampling and analysis are detailed elsewhere in this Work Plan:sediment/soil, WCC's QAPP; surface watst/^3.1.2; biota, 5.3.1.3; methods, Table 5-1; -lipid cleanup, EA's QAPP supplement 2.3.1; mass requirements, Table 5-2; detection limits,EA's QAPP supplement, Tables 2-1 and 2-2; time and collection procedures, EA's QAPPsupplement, Sections 5.3.1.2 and 5.3.1.3; matrix spike/matrix spike duplicates, Table 5-2.
Tissue data are required for specific comparative, modeling, and risk assessment purposes.Detection limits, quantitation limits, precision, and accuracy will be defined by the analysisand study purpose. The DQOs described herein (Figure 4-6) will provide sufficient accuracyand precision to meet the modeling objectives and characterize site-related risks. Within thelimits of available procedures, these analytical methods will provide quantitation limitscompatible with those employed for samples from other environmental media.
4.1.3.1 ARARs and TBCs for Tissue Samples
We will compile and apply ARARs for tissues (e.g., PDA action limits) at the site in thecontext of the pre-SARA ROD (1986). The Superfund Amendments and Reauthorization Actof 1986, Public Law 99-499, Section 122(a) (SARA), provides that, "the requirements ofSection 121 of CERCLA shall not apply to any remedial action for which the Record ofDecision was signed ... before the date of enactment." (Pub. L. 99-499, Section 122(b)).The Fields Brook ROD was signed on September 30, 1986, prior to the enactment of SARAon October 17, 1986. Therefore, ARARs to be compiled will comply with U.S. EPA'sunilateral 106 Order and the Facility Siting Design Investigation SOW. A preliminary listingof these possible ARARs is presented in Tables 2-1 and 2-2 of WCC (1990c).
4-9
t.atTENama:Ralda Brook 8QDI
NUMBER: aacapM fflfl2. MEDIA
3. USE
SOU.
ShaCharao. fat ^"̂IMH-.
GW
Attar. Eva).
SW/SED
Eng'g
EPARaoJonVmPHASE!
©PRPDalar. RAMc
4 OBiffiCTIVF SifflDft Wffta for aubttflutnt laboratory analvaia ID oallbrata a foohwih modal anad aa
5. SITE INFORMATIONAraa 5.B ao. ml. Daoth To QrourGroutSoilSana!
•>dwa*»rUat nona'ypM SJuf* badrook oovaradtfva Raoaptora BlotaarHfraon
6. DATA TYPES (********>A. Analytical Data
pH /conduct.dftb ' 1
AV8/SEM V
taaaddaj IUA"SO TOC
EnorganloD DOC
I&T cooBOD
7. SAMPLING MJjTH££bM.~MM •>..«*Qflvfr nmanttl] biaaad grab
OTHER
mftor. Ottw
•aaa ootantial riaka
idwatar | jtj tfim ffl ft,
bv drifttational Mlraot oBQttfitt
B. Physical Data
parmaabHlty hydraulicporoalty rtaadgrain aba panatraflonbuHcdanatty taat
turdnaaa
C. Biological Data
RBP com. atruo.aurvaywatinddaHn
nocHrrtruawa phaaadaouroa grid oompoana intrualva
8. ANALYTICAL LEVELS *—— *«*--.**—. *—-w
LEVEL 1 FMd Soraanlng <.,*...•)LEVEL 2 FMd Analyst *»*-«,LEVEL 3 Non-CLP Lab. iut,jjLEVEL 4 CLP/RAS(-— **LEVELS Non-Standard Sjf §QPj fraaantad In Addandum B. Chaotar 4
g. SAMPLING FBaokiCrttfo
• Proo
•ROCEDURESground - 2 oar avant or Th|«f mammala. ona tarraatrial vaoabttlon from two baokaround location*il -j.tduraa
10. QUALITY CONTROL SAMPLES (-*-.-—-*A.flaldCoUooatad r»*-i nonaRapHoata(B««i nonaFWd Blank «m«t nonaTrip Blank n_*.«> nona
B. LaboratoryRaagant BlanlRapUoalanp*Matrix Splkai
(ii.HM.hM*.! CLPProtoool.n.t. 1.1.1.1. •> CLP Protocol-— ̂ ..-̂ -i CLP Protocola o ^ — *„ mft\_r fn u n
11. BUDGET REQUIREMENTSBudgat N/A Sohaduto Sixlna/Summar 1003Staff Sampling Taam
Contractor EA EnoJnaaringSttaManaoar
Prlma Contractor Tach EnvtronmantalData
Figure 4-6. Data quality objective (DQO) summaiy form for biological samples.
4.1.3.2 Critical Samples for Tissue
Critical samples for quality assurance will be determined by analytical methods and willinclude blanks and laboratory duplicates as appropriate. The study as designed on the basisof environmental risk modeling does not rely on comparison with a "reference11 area for;: -me, because contaminant-associated risks in the Fields Brook floodplain may be quantifiedand are of primary interest. However, multiple samples from two reference sites will beincluded to determine background concentrations of potential contaminants.
4.2 SITE SAMPLING WORK PLAN DESIGN AND RATIONALE
Studies described in this work plan are designed to meet stated objectives of the floodplaincharacterization and to satisfy the specific DQOs. Data acquisition objectives for the FieldsBrook floodplain investigation include:
• Further defining the nature and extent of soil and sediment contamination ofthe Fields Brook floodplain;
• Characterizing bioavailability and bioaccessibility of identified contaminants atthe site. This program includes a set of soil studies which examinebioavailability of divalent metals (AVS-SEM), soil and sediment toxicitytesting, as well as biological tissue sampling for direct exposure analysis andto calibrate a site-specific food web model;
• Characterizing surface water quality at the ponded areas of the floodplain (SiteSection 8-2). These data will be used to assess the aquatic ecosystem, as wellas potential interaction with other components of the food webs (e.g.:piscivorous birds);
• Further defining the ecosystem characteristics of the wetland with HEP andWET;
4-10
• Completing a baseline ecological risk assessment of the Fields Brookfloodplain;
• Supporting risk management decision-making with reliable projections of risk.
As described above, a three stage investigation has been developed (Figure 4-1). Theprogram was initially implemented on a staged basis to allow results of the early stages to bereviewed prior to initiation of subsequent stages, in order to focus subsequent stages onidentified contaminants and receptors of concern. However, sufficient field activities havenow taken place to provide information for risk assessment components to proceedindependently of, and in parallel with, one another. The following sections describe theactivities performed in the ecological investigation of the Fields Brook floodplain.
4.2.1 Stage I Activities
4.2.1.1 Human Use Characterization
Human use characterization data will assist in screening possible exposure pathways byallowing quantitative estimates of the time, type, and intensity of human use of the area.Based on observations made during preliminary site reconnaissance (April 1992), human foodweb recreational exposure (fish and game consumption) may occur, and the level of suchactivities will be assessed. Other possible exposure routes will be evaluated as the usesurvey dictates.
Access to many areas of the Fields Brook floodplain is restricted by private property. Casualuse of these areas and of public-access portions is also restricted by dense vegetation.Despite these barriers, human recreational use of the floodplain does occur. Duringpreliminary reconnaissance, two tree stands (presumably for deer hunting) were observed,and the ponded area above the beaver dams showed evidence (paths, litter) of recent hook-and-line fishing.
4-11
Human use indicates both the potential value of the floodplain as a recreational resource andpotential exposure of humans to contaminants. To support risk evaluations, evidence ofhuman use throughout the watershed will be characterized by type and frequency. A surveywill be conducted of all portions of the watershed accessible to the field crew. Evidence ofhuman use (for example, trails, trash, hunting blinds or stands, footprints, fish or gamecarcasses) will be described in field notes and the approximate locatioifcfed on topographicmaps. Use frequency for all locations with evidence of human use will be categorized asfollows:
0 - No human use observed or expected. Areas of difficult access, or areas withno signs of human use.
1 = Infrequent human use: individual or small group (2-4 people) use possible atthis location approximately once a year or less often. Areas which showsingle tracks and/or single trash deposits receive this score,
2 = Moderate human use: individual or small group use possible at this locationseasonally, one or more persons expected at the location seasonally;
3 = Frequent human use: individual, small group, or large group (more than 4people) use possible at this locality at least weekly - areas which are easilyaccessible to residences or are clearly managed on a regular basis will receivethis score.
At least 25 locations throughout the watershed will be investigated to characterize humanuse. If this study intensity is insufficient to describe the human use patterns observed in thefloodplain, additional sites will be investigated. This investigation will follow the SOPpresented in Section 4 of EA's supplement to the QAPP.
It is important to understand that, while human "value" of the wetland system does not affectrisk quantitation, it plays a role in how ecological effects (e.g., tissue uptake of potentialcontaminants) are coupled to human health risk assessments (e.g., through fish and gameconsumption). Thus, the human use survey is included here for field convenience and
4-12
because measured body burdens from the ecological risk assessment may be employed inevaluating human health risks. In addition, a "human value" parameter plays a minor role indetermining the identified ROCs for the site. While this component is not part of formalavailable guidance, it is valuable for community relations and for assuring that all localconcerns are addressed. As this parameter plays a limited role in the assessment, but isimportant for completeness, it is retained in this assessmt.
4.2,1.2 Wetlands Ecosystem Characterization
Ecological characteristics (plants and animals present, litter layer depth and structure, habitatquality, disturbance levels) will be noted for biotic communities throughout the floodplain.Field notes will be cross-referenced to approximate locations noted on topographic maps. Inaddition to general notes on the floodplain ecosystem, field crews will specifically determine:
• Overt evidence of toxicant effects to vegetation or wildlife, including structuralor behavioral abnormalities (as qualitative evidence of organism health. Itshould be noted that these data will not be used for quantitative riskassessment);
• Evidence of natural or anthropogenic disturbance such as tree and brushcutting, storm damage, vehicle use;
• Degree of vegetation structure, presence and type of canopy, understory andherbaceous layers; and
• Type and extent of distinct habitat types (primarily vegetation communitiessupplemented by notes on substratum).
4-13
This information will support qualitative and quantitative evaluations of site habitat quality,potential contaminant effects, current levels of disturbance, and risk-of-remedy (potentialhabitat destruction associated with possible soil or sediment removal operations). Theseconsiderations are critical to an effective ecological risk assessment (USEPA 1989a & b,acknowledging that the latter document is not guidance but resulted from a U.S. EPA Officeof Policy and I^.'^opment workshop). In particular, data gathered during this investigationwill be used to:
• Quantify and map any areas of overt toxicant impact;• Quantify and map non-toxicant disturbance effects;• Document habitat types present;• Document habitat quality; and• Determine potential receptors-of-concern.
While specifically proposed for Stage I, this task will be ongoing and continue as an integralcomponent of all site field work. Since habitat quality varies both temporally and spatially,this continuing evaluation is critical for establishing the range of baseline conditions. Atleast 25 locations throughout the Fields Brook floodplain will be investigated to characterizehabitat conditions. Six locations throughout the floodplain (two locations in each of theupper, middle, and lower floodplain; Figure 5-1) will be further characterized using HEPand/or WET analysis for representative species in order to support and focus ROC selectionand food-web model development (see Section 5.3.1.5) by allowing screening of candidateROCs relative to presence of sufficient supportive habitat.
4.2.1.3 Sediment Transport Screening Analysis
An additional issue in evaluating potential risks associated with soils and sediments in thefloodplain is sediment transport potential. Observations made during the preliminary sitereconnaissance have revealed that the majority of areas within the Fields Brook watershed are
4-14
heavily vegetated, have stable soil, and are depositional in nature. However, specificlocations are erosional, particularly adjacent to stream banks in accessible and disturbedareas. A point-by-point screening analysis will be conducted to characterize the potentialsediment dynamics throughout the watershed.
Acx ' le locations along Fields Brook will be identified from topographic maps andpreliminary site reconnaissance notes. Transects perpendicular to the stream channel will beestablished at these locations on topographic maps. Several points along each transect willbe characterized in the field specifically for presence/absence of exposed (erodible) mineralsoil; depth of litter layer; presence, type, and degree of vegetation cover; and qualitative soilcolumn coherence and structure in accordance with EAF-SOP-ERS-0 (presented in EA'ssupplement to the QAPP). This characterization will be used to assess the degree and extentof potentially erodible soils in the Fields Brook watershed. Data analysis will include anevaluation of the occurrence frequency of potentially erodible soils, description of the soiltypes at each location, assessment of area potentially available for erosion, and the possibleimplications for contaminant distribution in the watershed. Specifically, data will support thebaseline risk assessment by allowing accurate characterization of the location and type ofsoils potentially susceptible to redistribution. Combined with data on the nature and extent ofcontamination present in the soil, this information will provide a quantitative evaluation ofthis potential exposure pathway. At least 25 transects with a minimum of 5 observationpoints each (a minimum of 125 sample locations) will be evaluated throughout the FieldsBrook floodplain to characterize soil erodibility.
4.2.2 . Stage II Activities
Stage II of this project consists of an evaluation of all known data regarding Fields Brookfloodplain, ultimately leading to a preliminary site characterization of the site, along withmodifying this EIWP to focus Stage III activities to collect additional data required tocomplete the risk assessment (Figure 4-1). The results of the human use characterization,
4-15
floodplain delineation, and sediment transport analysis will be assessed, in addition to anevaluation of existing data. Data to be examined, along with a description of what will beaddressed in the preliminary site characterization are discussed below.
4.2.2,1 Review of Existing Data
Existing data regarding the Fields Brook floodplain have been summarized in Table 4-1.The brief examination of these data has shown that volatile and semi volatile organiccontaminants tend to be concentrated around the location of Reach 5-2. Preliminary analysisof metals data indicates that selected metals appear to be present above typical EasternUnited States soils (Shacklette and Boerngen 1984), specifically arsenic, barium, beryllium,chromium, copper, lead, mercury, nickel, selenium, and zinc. It is not possible to estimatethe probability of risk to ecological receptors due to potential exposure to either the organicchemicals or metals at this time. These data will be used in conjunction with the Phase IISQDI data for risk characterization, however, a preliminary analysis will occur during thisphase of this study to support ROC and COC selection. In addition, an attempt to investigatespatial variability of potential contaminants will occur during this stage.
4.2.2.2 Preliminary Site Characterization
There will be three main tasks involved in the preliminary risk characterization. These are:
• Habitat/Use evaluation• Receptor of Concern (ROC) selection and• Contaminant of Concern (COC) selection.
These tasks are briefly described below,
4-16
The habitat/use evaluation will assess the extent to which the floodplain is used by bothhumans and other receptor organisms. For example, a count of deer stands or evidence offishing in the ponded areas of the floodplain will directly implicate human use of the site.Evaluation of the value of the wetland will assist in determining its use by other potentialreceptors, such as beaver, deer, and piscivorous birds. The analysis of vegetation willindicate the floodplain's value as a food source to herbivorous receptors.
EA will identify ROCs in a screening process based on existing information, sitereconnaissance, and a semi-quantitative ranking model which provides a sound, objectivebasis for focusing on particular species. The approach applies a pairwise factor weightingtechnique (Dean and Nishry 1965, Canter 1977) to develop a numerical score for a numberof relevant criteria for each included species. Individual ROCs can then be selected fromamong those scoring highest on the criteria scale. This will provide focus to the assessmentand improve cost-efficiency by limiting the assessment to key taxa.
Development of specific criteria for ROC identification requires an evaluation of informationobtained from site reconnaissance and existing sources. In general, criteria will be selectedto address key issues relating biological receptors to contaminant exposure and utility for riskmanagement decision-making. Although the PCT process will likely redefine selectioncriteria, criteria currently proposed for ROC selection are:
• Seasonality of Site Use: Degree to which organisms are likely to be exposed tocontaminated media;
• Trophic status: Level in food-web and propensity to bioaccumulate highconcentrations of contaminants, and value in overall ecosystem function;
• Habitat Type: Degree of direct contact with contaminated materials;• Regulatory Status: Includes level of regulatory protection (for example,
protection under the Endangered Species Act, 16 U.S.C.A. 1531 et seq.) anduse for recreational and commercial harvest;
4-17
• Practicality: Usefulness in risk assessment/risk management, obtainability ofspecimens, difficulty in handling samples or interpreting results.
Application of the screening process will yield a suite of receptors of primary concern, and acorresponding suite of taxa which may be employed effectively as surrogate or representativespecies to assure successful sampling and fully sJH»*ess key issues related to exposure ofbiological receptors. The information base for developing criteria and suites of receptorswill include existing site-specific reports, data, and information; published studies on theecology and biology of the species present or potentially present on site, and data gatheredduring Phase II SQDI field activities (including HEP analysis). The purpose of the HEPanalysis is to employ quantitative techniques to determine whether habitat quality is sufficientto support certain candidate ROCs. For example, if a candidate ROC is known to be presentin the general area, but necessary habitat components are not present in the Fields Brookarea, this candidate might be of lower value as an ROC than an ecologically similarsurrogate.
COCs for biological receptors will be identified with a paired-factor weighting analysis in afashion analogous to that used to identify ROCs. COCs will be identified based on anintensive sampling effort characterizing contaminant concentrations in environmental media,and the weighting factors proposed here assume that that effort has occurred prior to finalCOC identification. Existing information will be screened for contaminant concentrationmeasurements. The list of contaminants presented (Table 4-1) will then be analyzed byapplying applicable criteria in the paired-factor context. This selection process will occurtwice during the project: once based on existing information to prepare the preliminary riskcharacterization and again based on the full suite of SQDI Phase II data to prepare thecomplete risk characterization. Although the PCT process will likely redefine selectioncriteria, proposed criteria which address key aspects of environmental fate and effects ofcontaminants in the ecosystem are:
4-18
• Toxicity Quotient: The ratio of the toxicity of the compound to one or severalROCs (as determined from appropriate literature) to the concentrationsobserved in Phase I and Phase II SQDI floodplain samples;
• Bioaccumulation potential: Tendency of the chemical to bioaccumulate intissues of ROCs. Octanol-water partition coefficient (Kow) will be used fororganic compounds and bioconcentration factors (BCF) will be used for metalsand metal-based cornounds;
• Ubiquity: Detection frequency in Phase I and Phase II SQDI flood-plainsamples.
For COCs, a "threshold" contaminant will be included in the ranking process which mayhave the following characteristics:
• Toxicity Quotient = 1.0: Chemical is expected to exhibit toxic responses insome ROCs at observed environmental concentrations;
• Kow or BCF = 1,000: Based on information presented in U.S. EPA (1991c),"bioconcentratable" materials are generally considered to be those which areobserved in tissues at a concentration 1,000 times or more of abiotic mediaconcentrations. Although this factor does not address effects of these materialson receptors, it does address propensity to move through the food-web;
• Detection Frequency = 10%: Chemical is sufficiently widespread to warrantcomplete risk assessment.
All chemicals which rank higher than this "threshold" contaminant will be considered to posesufficient ecological risk to be retained for complete ecological risk assessment. It isimportant,to note that failing any one of these criteria (e.g., detection frequency of 10%)does not necessarily drop the chemical from the list of COCs because toxicity andbioaccumulation potential also serve an important role in COC determination. For example,depending on the factor weights assigned, a chemical with a detection frequency of only 1 %which was found to be present at highly toxic concentrations and which has a high potentialto move through the food-web will be very likely to be assigned COC status (exceed the"threshold" characteristics) regardless of the low frequency of detection.
4-19
Developing and applying specific criteria to address each of these components of fate andeffects will support an objective, scientifically sound process by which further sampling andanalysis efforts can be concentrated on key compounds. This process will maximize thetechnical strength and cost-effectiveness of the investigation, and focus efforts on thesubstances of greatest concern for the environment from scientific, regulatory, and thirdparti' perspectives.
Since Stage I activities may be performed at different times, as many reports as are needed todocument all the activities will be produced. These reports will discuss preliminary ROCand COG selection and the initial risk estimates.
4.2.3 Stage III Activities
Stage HI builds on data gathered to date to support identification of locations for limitedfocused additional field studies and quantitative risk analysis. The configuration of Stage IIIactivities (sample locations, distribution of samples, data analysis techniques) is intended tobe flexible to incorporate information derived from Stages I and II, although some Stage Iand II activities will take place concurrently with Stage III field activities. Stage HI activitiesare discussed in detail in Section 5 below, which describes each Stage III task and providestechnical rationale.
Briefly, Stage III will consist of field studies as necessary for biological tissue contaminantanalyses; benthic community structure analysis in the ponded area of reach 8; detailedwetland habitat evaluation to assess wetland quality; toxicity studies of a representativeinvertebrate organism (earthworm); community structure analysis of soil fauna (by pitfalltrapping), and AVS/SEM evaluation. These studies, other available information, and theresults from Stages I and II are integrated in Stage III into the baseline quantitative ecologicalrisk assessment. Thus, Stage III is a synthetic component of the investigation, and leadsdirectly to conclusions and recommendations from the RI program as a whole.
4-20
4.2.3.1 Acid Volatile Sulfide / Simultaneously Extracted Metals
In a fashion analogous to the binding of organic contaminants by TOC, some metals arebound to certain compounds in the sediments, potentially reducing their bioavailability. Thiseffect ljas been studied, and its utility is currently being developed (e.g., Ankley et al. 1991,Di Toro et al. 1990). While formal guidance does not specify the utility of this parameter, itcan be helpful in interpreting findings of ecological risk assessment. While we will not usethis parameter to predict risks, we will employ it in interpreting and explaining findings. Itshould also be noted that uncertainty associated with AVS/SEM cannot be quantified at thistime and for this reason a qualitative discussion of uncertainty will be included in the finalreport along with interpretive discussions.
Acid Volatile Sulfides (AYS) represent amorphous iron sulfides present in sediments andsoils which are readily broken apart releasing hydrogen sulfide (H2S). H2S reacts withdivalent metal ions (Cd+2, Cu+2, Ni+2, Pb+2, and Zn+2) forming insoluble and non-biologically available metal sulfides (DiToro et al. 1990; Carlson et al. 1991; Ankley et al.1991). These compounds are termed Simultaneously Extracted Metals (SEM). Whensufficient AYS is available, potentially toxic metals are bound in the soil and sedimentsystem, bioavailability is low, and no toxicity has been observed attributable to these metals.When insufficient H2S is available, the excess SEM is available to organisms and may beexpressed in measurable toxicity. This process is additive for SEM, therefore for completeSEM analysis:
SEM = E [MetaT2] = [Cd+2] + [Cu+2] + [Ni*2] + [Pb+2] + [Zn+2]
This effect has been studied using numerous organisms including amphipods, mussels, grassshrimp, hard shell clams, worms, snails, and oligochaetes. All of these studies have shownno toxic effects when sufficient AYS is available. We will be sampling and analyzingAVS/SEM in the Fields Brook floodplain to screen potential toxicity associated with thesefive metals. Data Quality Objectives for AVS-SEM are shown in Figure 4-3.
4-21
5. ECOLOGICAL INVESTIGATION
This section describes the field sampling methods for various activities in the stagedecological investigation. Where particular aspects of the number and location of samples,sample numbering system, sample matrices, and the level of sampling quality control forfield activities on the Fields Brook floodplain require additional discussion bey-md thatpresented above, this information is included. Field sampling will include surficial (upper 6or 12 inches) soil and sediment samples (described in the main body of this workplan),surface water samples from the ponded area of the floodplain, biological tissue sampling, awetlands characterization using the Fish and Wildlife Service's Habitat Evaluation Procedure(HEP), soil and sediment toxicity testing using earthworms, benthic community structureanalysis of the ponded areas in the floodplain, and pitfall trapping of soil biota.
In addition to field data collection, this project will include ecological risk modeling;contaminant assessment, and an ecological risk assessment. The primary objective is todevelop documentation sufficient to fully evaluate the need for further remedial measuresbased on a baseline risk assessment of the Fields Brook floodplain. Specific data needs anddata quality objectives (DQOs) have been addressed previously in Chapter 4.
The relative roles of data and risk projection through model calculation are crucial to thesuccess of the overall risk assessment. In general, quantitative risk assessment conclusionsare based on measured data on contaminant concentrations in environmental media and biotictissue and on parameters partially controlling biotic exposure such as total organic carbon.For risk projection to taxa not sampled or to investigate potential risk management scenarios,a food web model, parameterized with site data, is a potentially valuable tool. A simplifiedschematic food web is illustrated in Figure 4-5. This model will be modified with regard tospecific ROCs selected for the site and will be parameterized based on findings of thecontaminant nature and extent surveys. The model will then be used to calculate possiblecontaminant doses by incorporating information in feeding rate and feeding fractions for eachreceptor at each trophic level. These specific parameters cannot be presented until ROC
5-1
selection is complete. The model will be run stochastically to allow characterization ofquantitative uncertainty around risks projected for various scenarios. Assumptionsfundamental to the modeling effort are: 1) that doses can be described with reasonableaccuracy based on dietary intake and/or direct exposure to environmental media; 2) thatdoses can be compared with reasonable accuracy to toxicity reference values available in ormodified from the literature; 3) that the contaminant nature ant v^nt survey adequatelydescribes the distribution of contamination in the Fields Brook wetlands; and 4) thatsufficient data are available to parameterize and calibrate the model. Because of theintensive nature of the sampling surveys, data to support the modeling effort are expected tobe adequate. It is important to note that the model is used only as a tool to supplement thebasic risk evaluation which is founded in measured contaminant concentrations. The modelsimply allows projection of findings to risk management scenarios under conditions thatcannot presently be measured. The model itself is only a logical construct of feedingbehaviors of the ROCs and as such it will be presented in detail in the final project report.The model represents the site-specific food-web as determined by the findings of the fieldsampling program.
The following sections describe the major components of field, modeling, and reportdevelopment activities for this study. The field sampling procedures described herein will beconducted in accordance with the health and safety provisions described in the supplement tothe Site Health and Safety Plan. Chemical quality assurance and quality control will be inaccordance with provisions discussed in EA's supplement to the project QAPP.
5.1 STAGE I INVESTIGATION
The Stage I investigation will include qualitative and quantitative evaluations of specific keyaspects of ecosystem structure and function in the Fields Brook watershed. These activitiesand their rationale are documented in Section 4 above. Below we present the specificmethods used to obtain data for each activity.
5-2
5.1.1 Human Use Characterization
Methods for human use characterization will be observational. As described in Section 4,field crews will note presence or absence of any evidence of human use. Accessiblelocations along Fields Brook will be identified from topographic maps and preliminary sitereconnaissance notes. Observations obtained at each location will be recorded on site mapsand will indicate the frequency, relative intensity, and total area (or linear distance ofstreambank) subject to human use. Data quality will be maintained by employing aconsistent suite of parameters as the basis for each observation point. The parameters to beused include: presence of trails, presence and type of trash, presence and type of huntingstand, presence and type of fishing activities, number and identity of fish and gamecarcasses, estimated time of last use, and estimated number of people. A detailed SOP ispresented in Chapter 4 of EA's supplement to the project QAPP. Additional observationsmay be made, but the fundamental data will be acquired under a uniform procedure to assureaccuracy. Two observers will be present at each location, and notes will reflect a consensusevaluation. Data quality will be sufficient to assure accurate characterization of human usepatterns in the floodplain. This investigation will be conducted in accordance with the SOPpresented in EA's supplement to the project QAPP.
5.1.2 Wetlands Ecosystem Characterization
Methods for floodplain ecosystem characterization will be observational and will besupplemented with quantitative measurements as discussed in Section 5.3.1.5 (HEP analysis)below. As described in Section 4, field crews will note specific aspects of the habitat, biotapresent, and overt toxicant effects. Data quality will be maintained by employing aconsistent suite of parameters as the basis for each observation point. The parameters usedinclude: type and intensity of vegetation damage or chlorosis, fish and wildlife presence, fishand wildlife gross condition, presence, type, and intensity of disturbance, presence, height,
5-3
and type of canopy, presence and type of understory, presence and type of herbaceous layer,habitat type and observed biota. The results will be used to support both qualitative andquantitative assessment. Additional observations may be made, but the fundamental data willbe acquired under a uniform procedure to assure accuracy. Two observers will be present ateach location, and notes will reflect a consensus evaluation.
5.1.3 Sediment Transport Screening Analysis
Methods for soil erodibility characterization will be observational. As described in Section4, field crews will note specific aspects of soil quality, litter layer, and vegetation cover.Data quality will be maintained by employing a consistent suite of parameters as the basis foreach observation point in accordance with the SOP presented in EA's supplement to theproject QAPP (EAF-SOP-ERS-0). Parameters to be used include: presence and type ofexposed mineral soil, depth of detritus layer, presence and type of vegetation cover, andqualitative soil column coherence and structure. The information obtained will be used tosupport both qualitative and quantitative assessment. Additional observations may be made,but the fundamental data will be acquired under a uniform procedure to assure accuracy.Two observers will be present at each location, and notes will reflect a consensus evaluation.
5.2 STAGE II INVESTIGATION
Stage II activities include analysis of existing data and preliminary risk characterization.
Existing data will be analyzed from the perspective of potential ecological risks. Graphicaland mapping techniques will be employed for examination of potential trends. Statisticalanalyses will be used if possible for comparisons and to define thresholds. Preliminarycomparison of existing data with available criteria was conducted as a means to focus Stage
III activities.
5-4
Preliminary risk characterization is primarily the objective identification of limited suites ofcontaminants and receptors of concern based on available information, site visits, the knownenvironmental chemistry and toxicity of contaminants, and literature regarding thesusceptibility of native species to toxicant effects (both physiological and ecological). Theprimary method for identifying both COCs and ROCs is a paired-factor weighting technique(Dean and Nishry 1965, O ;.7 1977) applied to the relative hazard ranking model for sitecontaminants developed by Halfon and Reggiani (1986). The principle of the pairedcomparison analysis is to reduce the decision making process to individual elements such thata numerical score can be developed for each element based on pertinent information(factors). The first step in the process is to make comprehensive lists of compounds andfactors. Comparison factors will be selected with the unique characteristics of the site inmind. Among those which may be important are: occurrence frequency in samples, averagebioavailable concentration, potential toxicity, tendency to bioaccumulate, and environmentalpersistence.
Once identified, factors (Section 4.2.2.2) are weighted for relative importance. For example,toxicity is a direct measure of potential effect, and might be weighted more heavily thandetection frequency (a simple measure of presence). The PCT process is designed to makethe weighting process as objective as possible. This is done by pairwise comparison of everyfactor to every other factor. Once factors receive relative weights, each contaminant isscored for each factor and compared one at a time with every other compound, one factor ata time. Each contaminant score is multiplied by the factor weights, and results are summedfor each compound. Compounds can now be ranked relative to their potential to drive riskto ecological receptors and can be ranked relative to a "threshold" below which noappreciable risk is presumed to exist (Section 4.2.2.2).
The result of the COC selection is an objective "short list" of COCs on which to focusfurther efforts. Analysis time and money can be saved if analytical extracts and individualmetals can be screened out of the assessment process at this point. Substantial time and
5-5
effort is saved in any case by focusing risk assessment interpretive efforts on the mostimportant site contaminants.
The paired comparison is applied to each species weighted on each factor, and a ranking ofpotential ROCs is obtained. "Target" ROCs are easily defined from the top-ranked species,although this si^ »d be done flexibly. For example, it may be wise for a particular site totarget the top ranked species in each trophic category. In any case, considerable flexibilitywill be built in to the ROC selection process to assure successful Stage III modeldevelopment and evaluation.
Further discussion and an example of the process was provided to USEPA under a coverletter dated 12 May 1993 from Phil Clifford to Edward Hanlon and should be referred to formore detail regarding the process.
5.3 STAGE HI INVESTIGATION
EPA and Federal natural resources trustees have identified potential ecological concerns forthe Fields Brook floodplain. An ecological risk evaluation will be used directly fordeveloping and interpreting study results. Ecological risk assessment will be conducted inaccordance with applicable agency guidance (U.S. EPA 1989a & b, 1992a, 1992b). Inaddition, since ecological impacts may yield key concerns for the Fields Brook floodplain,the ecological risk assessment will be innovatively and actively employed as an investigatorytool for this project. The utility of the assessment is illustrated in Figure 4-1. This figureshows how the ecological evaluation, refined on the basis of ongoing data acquisition,supports sampling and interpretation decisions. This iterative approach focuses theinvestigation on key environmental receptors and those most likely to be at potential risk.This focus in turn permits scientifically sound decisions to be made regarding remedialoptions.
5-6
Issues to be addressed in the ecological risk evaluation include the following:
• Uptake mechanisms (what media are driving tissue acquisition?);• Key receptors present or potentially present in the Fields Brook floodplain (in
keeping with guidance, this will include re-evaluation of endangered orthreatened species);
• Food-web interactions (including potential food-web-based risks to ecologicalreceptors);
• Potential direct toxicity to ecological receptors as a result of exposure to FieldsBrook floodplain contaminants.
Modeling will employ a series of simple equations linking environmental contaminantconcentrations to various components of the food web. These equations are composed ofquantity of food consumed and concentration of COCs in food consumed (determinedempirically from field collections and analysis). When concentrations of COC in dietaryitems are not explicitly measured in field evaluations, bioaccumulation factors (either fromavailable literature or determined during field studies) will be used to estimateconcentrations. This framework allows for sampling of relevant environmental compartmentswithout the ecological risk assessment model being finalized since low-uncertaintyextrapolations can be made from measured compartments to compartments required by themodel. Risks are then computed by comparing calculated dose (concentration of COC timesmass consumed equals dose) to a dose-based toxicity reference value (TRY). When the ratioof dose to TRY exceeds 1.0, potential risk may be present. Since one of the tasks under thisworkplan is development of a list of ROCs, the food-web model does not, as such, yet existand can therefore not be presented in final form. One of the principal goals of the draft finalreport will be to present the model in its entirety for review and modification.
It is expected that semivolatile organic chemicals such as PCBs will be an important concernfor tissue acquisition and bioaccumulation factors can therefore be used to predict bodyburdens at various levels in the food web if required. Site-specific biota inventories will be
5-7
generated to develop a trophic web. Criteria used to select individual key receptors havebeen discussed in the ROC selection process (Section 5.2). Resources at risk will beprojected from the food webs and bioaccumulation factors. Body burden samples (Stage III,including those taken in fish tissue) will include organisms at greatest potential risk ofacquiring high tissue levels as required for food-web modeling. Should rare, threatened, orendangered species be projected to acquire high tissue levels, surrogate species will besampled. It is difficult to specify in advance what species would be the most likely targetsfor tissue analyses, because potential tissue levels are determined by site-specific food webswhich must be developed. Actual field collection will be driven by species present, and willbest represent the actual site-specific food-web. For this reason, acquisition effort, ratherthan specific species, are referred to throughout the remainder of this workplan.
The modeled food-webs will be based on the generic food-web presented in Figure 4-5. Forexample, organisms which feed lower in the trophic web (e.g., amphibians or invertebrates)may provide a more effective indication of overall tissue uptake than examination oforganisms which feed on them if the organisms higher in the food web spend less time incontaminated locations of the floodplain or if the COC of interest is not bioaccumulative innature.
Each of the listed issues is discussed below, with a brief statement of the problem and thetechnical approach that will be taken.
Uptake Mechanisms
Substantial information exists in literature sources on both the ecological dynamics of GreatLakes ecosystems and on the biodynamics of bioaccumulative chemicals such as PCB andmercury. This information will be considered in conjunction with existing site data, and datato be acquired on water and soil and sediment concentrations during Stage III to develop amodel of contaminant accessibility, availability, and uptake. Modeled estimates will besupported and verified by samples of tissue and environmental media. Estimated and verified
5-8
uptake mechanisms will provide technically defensible information for evaluating remedialoptions by supporting calculation of hazard quotients (ratio of dose to TRY) for ROCsdirectly from site-specific data.
Kev Receptors
As discussed earlier, it is difficult to predict ROCs in advance, however, based on bestprofessional judgement of the site, principle ROCs for the site are expected to include deer,small mammals, water birds (e.g., geese, ducks, herons, egrets, and grouse), and raptors(e.g., kestrels, other hawks, and owls). Because ingestion is the primary route ofcontaminant exposure to these ROCs, this study will focus on concentrations of COCs notonly in abiotic media, but also in both dietary items and ROCs. Water and soil ingestionwill be evaluated for significance and will be quantified (if necessary) based onenvironmental media concentrations. Non-ingestion exposure routes (direct contact, air, etc.)will be addressed qualitatively. ROCs and dietary items to be sampled preliminarily includemice and other small mammals, insects, benthic macroinvertebrates (benthos), and terrestrialand aquatic plants. As discussed earlier (Section 4.2.2.2), ROCs will be selected duringStage II and III using a semi-quantitative analysis.
Food Web Interactions
Food web interactions are the key to understanding biotic uptake and accumulation of PCBsand mercury. An ecological risk model which incorporates a detailed evaluation of the roleof trophic interactions in determining contaminant dynamics in the Fields Brook floodplainecosystem (discussed above; Figure 4-5) will be employed in risk assessment. Fieldobservations, existing data, and available literature have provided sufficient information togenerate a preliminary conceptual model for this site, however, it is important to note thatthe exact structure and receptors to be used in the model will be selected during the receptorof concern (ROC) process during Stages II and III. All assumptions associated with the finalversion of the model (in addition to those listed herein) will be documented in the final
5-9
project report. Stage III sampling data will be used to calibrate the model, verify modelpredictions, and further define any potential environmental effects of contamination.
Potential Direct Toxicity
Potential direct toxicity to ROC flowing exposure to COCs will be assessed in a numberof ways. These include soil and sediment toxicity testing using earthworms, examination ofsoil and sediment acid volatile sulfide and simultaneously extracted metals to assess directtoxicity of divalent heavy metals, as well as comparison of measured biological tissuechemical concentrations to toxic reference values. This analysis will assess the potentialimpacts of nonbioaccumulative chemicals such as volatile organics.
5.3.1 Focused Field Studies
5.3.1.1 Sediment/Soil Analyses
Since the purpose of sampling in the floodplain is to supplement existing data on the FieldsBrook floodplain, the areas identified as proposed floodplain sampling for this study wereevaluated for appropriateness as biota, soil and sediment, and surface water samplinglocations. Evaluations were based on information obtained during site reconnaissancerelating to habitat quality, quantity, and diversity. These areas and sample quantities areidentified in Table 4-2 and in the following text. This information provided input to samplelocations detailed in Figure 5-1. EA's supplement to the project QAPP presents completediscussion of methods of sampling and analysis for soil and sediment characterizationincluding a specific SOP for sampling.
Methods for Acid Volatile Sulflde/Simultaneously Extracted Metals analysis are described indraft guidance (USEPA 1991b) and are described in detail in the SOP presented in EA'ssupplement to the project QAPP. We have worked with these methods and found them
5-10
= Biota Sampling Location
LowerUpper
Figure 5-1. Proposed biota sampling locations along the main-stem of FieldsBrook. Numbers refer to reaches.
effective, yielding data of high quality. We will apply these methods for AVS/SEManalyses.
5.3.1.2 Surface Water Analyses
There is only one extensive and relatively permanent ponded area within the Fields Brookfloodplain, specifically the beaver pond contained within Reach 8-2. At this stage, triplicateanalyses of the parameters shown in Table 5-1 (three separate samples each analyzed for eachparameter) are proposed for this surface water. These data will be used to assess directtoxicity, as well as to serve as a component input to the aquatic food web.
5.3.1.3 Biological Tissue Contaminant Analyses
A total of 69 samples of ROC tissue and dietary items for ROCs are proposed for collectionand analysis (Table 5-2). Potential organisms to be sampled include terrestrial plants(browse for deer and lower consumers), aquatic plants, benthic macroinvertebrates, and fish(food for water birds), terrestrial insects (such as grasshoppers and ground beetles, forage forkestrels), and small mammals (such as mice and shrews as food for other raptors).
The focus of the body burden sampling will be on individual species within each receptorcategory to assure adequate number of samples to describe tissue concentrations andassociated uncertainty. These samples will be concentrated on organisms likely to bemaximally exposed to COCs and/or to be crucial components of the food webs of key ROCs.In this assessment, sampled taxa represent other taxa of similar exposure potential. Thus,ecological risks can be assessed comprehensively (within the limits of uncertainty which willbe quantified on the basis of variability inherent in the data) for ROCs throughout the FieldsBrook wetland area. As no inventory of species abundances at Fields Brook currently exists,specific species to be sampled cannot be determined at this time. Rather, degree of tissueaquisition effort will be discussed herein and actual catch will be driven by the actualabundances at the site. This methodology will allow characterization of the food-web as well
5-11
TABLE 5-1 ANALYTES, CAS NUMBERS, AND ANALYTICAL METHODS
Analyte Class Analyte CAS# Number
Volatile Organics
Chloromethane 74-87-3
Bromomethane 74-83-9
Vinyl chloride 75-01-4
Chloroethane 75-00-3
Methylene chloride 75-09-2
Acetone 67-64-1
Carbon disulfide 75-15-0
1,1-DichIoroethene 75-35-4
1.1-Dichloroethane 75-34-3
1.2-Dichloroethene (total) 540-59-0
Chloroform 67-66-3
1,2-Dichloroethane 107-06-2
2-Butanone 78-93-3
1,1,1-Trichloroethane 71-55-6
Carbon tetrachloride 56-23-5
Vinyl acetate 108-05-4
Bromodichloromethane 75-27-4
1,2-Dichloropropane 78-87-5
cis-l,3-Dichloropropene 1006-01-5
Trichloroethene 79-01-6
Dibromochloromethane 124-48-1
1,1,2-Trichloroethane 79-00-5
.Benzene 71-43-2
trans-l,3-Dichloropropene 10061-02-6
Bromoform 75-25-2
4-Methyl-2-pentanone 108-10-1
CLP SOW 3/90
TABLE 5-1 Continued
Analyte Class Analyte CAS# Number
Volatile Organ! cs(continued)
2-Hexanone
Tetrachloroethene
1,1,2,2-Tetrachloroethane
Toluene
Chlorobenzene
Ethylbenzene
StyreneXylene (total)
Semivolatiles (BNA)
3-Nitroaniline
Acenaphthene
2,4-Dinitrophenol
4-NitrophenolDibenzofuran
2,4-DinitrotoIuene
Diethylphthalate4-Chlorophenyl-phenylether
Fluorene
4-Nitroaniline
4,6-Dinitro-2-methytphenol
N-Nitrosodiphenylamine
4-Bromophenyl-phenylether
Hexachlorobenzene
Phenanthrene
CLP SOW 3/90
591-78-6
127-18-4
79-34-5
108-88-3
108-90-7
100-41-4
100-42-5
1330-20-7
CLP SOW 3/90
99-09-2
83-32-9 SW 8100
51-28-5
100-02-7
132-64-9
121-14-2
84-66-2
7005-72-3.
86-73-7 SW 8100
100-01-6
534-52-1
86-30-6
101-55-3
1 18-74- 1 Pesticide/PCB'"
85-01-8 SW 8100
TABLE 5-1 Continued
Analyte Class Analyte CAS# Number
Semivolatiles (BNA)(continued)
Anthracene
Di-n-butylphthalateFluoranthene
Pyrene
Butylbeozylphthalate
3,3'-Dichlorobenzidine
Benz(a)anthracene
Chrysene
bis(2-Ethylhexy!)phthalate
Di-n-octylphthalate
Benzo(b)Duoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Indeno(l,2,3-cd)pyrene
Dibcnzo(a,h)anthraccne
B e nzo (g,h, i) perylenc
Phenol
bis(2-Chloroethyl) ether
2-Chlorophenol
1,3-Dichlorobenzene
1,4-DichlorobenzeneBenzyl alcohol
1,2-Dichlorobenzene
2-Methylphenol
bis(2-Chloroisopropyl)cther
120-12-7
84-74-2
206-44-0
129-00-0
85-68-7
91-94-1
56-55-3
218-01-9
117-81-7
117-84-0
205-99-2
207-08-9
50-32-8
193-39-5
53-70-3
191-24-2
108-95-2
111-44-4
95-57-8
541-73-1
106-46-7
100-51-6
95-50-1
95-48-7
108-60-1
CLP SOW 3/90
SW8100
SW8100
SW8100
SW8100
SW8100
SW8100
SW8100
SW8100
SW8100
SW 8100
SW8100
TABLE 5-1 Continued
Analyte Class Analyte
SemivolatUes (BNA)(continued)
4-Methylpheno!N-Nitroso-di-n-propylamine
Hexachloroethane
Nitrobenzene
Isophorone
2-Nitrophenol
2,4-Dimethylphenol
Benzoic acid
bis(2-Ch!oroethoxy) methane
2,4-Dichlorophenol
1 ,2,4-Trichlorobe nzene
Naphthalene
4-ChIoroaniline
Hexachlorobutadiene
4-Chloro-3-methylphenol
2-Methylnaphthalene
Hexachlorocyclopentadiene
2,4,6-Trichlorophenol
2,4,5-Trichlorophenol
2-ChloronaphthaIene
2-Nitroahiline
Dimethylphthalate
Acenaphthylene
2,6-Dinitrotoluene
CAS#
106-44-5
621-64-7
67-72-1
98-95-3
78-59-1
88-75-5
105-67-9
65-85-0
111-91-1
120-83-2
120-82-1
' 91-20-3
106-47-8
87-68-3
59-50-7
91-57-6
77-47-4
88-06-2
95-95-4
91-58-7
88-74-4
131-11-3
208-96-8
606-20-2
Number
CLP SOW 3/90
SW8100
SW8100
TABLE 5-1 Continued
Analyte Class Analyte CAS# Number
Pesticides/PCBs
a-BHC
0-BHC
6-BHC
-y-BHC (Lindane)Heptachlor
Aldrin
Heptachlor epoxide
Endosulfan I
Dieldrin
4'4'-DDE
Endrln
Endosulfan II
4'4'-DDD
Endosulfan sulfate
4'4'-DDT
Methoxychlor
Endrin kelonea-Chlordane
7-Chlordane
Toxaphene
ArocIor-1016
Aroc lor- 1221
Aroclor-1232
Aroclor-1242
Aroclor-1248
Aroclor-1254
Aroclor-1260
CLP SOW 3/90
319-84-6
319-85-7
319-86-8
58-89-9
76-44-8
309-00-2
1024-57-3
959-98-8
60-57-1
72-55-9
72-20-8
33213-65-9
72-54-8
1031-07-8
50-29-3
72-43-5
53494-70-5
5103-71-9
5103-74-2
8001-35-2
12674-11-2
11104-28-2
11141-16-5
53469-21-9
12672-29-6
11097-69-1
11096-82-5
TABLE 5-1 Continued
Analytc Class
Metals
Acid Volatile Sulfide-AVS
SimultaneouslyExtracted Metak-SEM
Analyte
Aluminum (Al)m
Antimony (Sb)Arsenic (As)
Barium (Ba)w
Beryllium Be)
Cadmium (Cd)
Calcium (Ca)w
Chromium (Cr)Cobalt (Co)*»Copper (Cu)
Iron (Fc)w
Lead(Pb)
Magnesium (Mg)**
Manganese (Mn)**Mercury (Hg)Nickel (Ni)
Potassium (K)w
Selenium (Se)Silver (Ag)
Sodium (Na)w
Thallium (Tl)Vanadium (V)*»Zinc(Zn)
Cadmium (Cd)
Copper (Cu)
GAS* NumberCLP SOW 3/90
7429-90-5
7440-364)7440-38-27440494
744041-7
7440-43-9
7440-70-2
7440^7-3
7440-48-4
7440-504
7439-89-67439-92-1
7439-95-4
7439-96-5
7439-97-67440-02-0
7440-09-7
7782-49-2
7440-22-4
7440-23-5
7440-28-0
7440-66-6
7440-66-6
U.S. EPA 1991W (SOPattached)
CLP SOW 3/90
7440-43-9
7440-50-8
'̂ ^^p
TABLES-1 Continued
Analyte Class
SEM (continued)
Analyte
Nickel (Ni)
Lcad(Pb)Zinc(Zn)
CAS#
74404124)
7439-92-17440-66-6
Number
CLP SOW 3/90
Inorganic
Physical Parameters
Cyanide
Upid analysis*0
Total organic carbonw
Hardness'"Alkalinity"1
pH*
Temperature10
Dissolved oxygen*0
Conductivity"
Light penetration"
57-12-5 CLP SOW 3/90
CLP SOW 3/90
EPA 130.2
SOP attached (fieldmeasurement)
EPA 150.1 (fieldmeasurement)
(field measurement)
EPA 360.1 (fieldmeasurement)
EPA 120.1 (fieldmeasurement)
Lind 1974 pp. 16-23W
(a) Hexachlorobenzene will be analyzed in the pesticide/PCB analysis to achieve lower detection limits.
(b) These metals will be analyzed only for total and dissolved metals in surface water.
(c) U.S. EPA 1991. Draft Analytical Method for Determination of Acid Volatile Sulfide in Sediment.United States Environmental Protection Agency, Office of Science and Technology, Health andEcological Criteria Div., Washington, D.C. August 1991.
(d) Analysis of lipids only in biological tissues.
(e) Analysis of total organic carbon in soil/sediment only.
(f) Analysis of these parameters will only be for surface water.
(g) Lind, O.T. 1974. Handbook of Common Methods in Limnology. C.V. Mosby Company, Saint Louis.pp. 16-23.
TABLE 5-2 SAMPLE SIZE REQUIREMENTS FOR TISSUE ANALYTICALMETHODS*'*
Analytes of Interest RequiredQuantification Size
(g wet weight)
Required QA-QCSize (g wet weight)
Total Sample Size(g wet weight)
Volatile OrganicChemicals
Base/Neutral/Acidic Organic
ChemicalsPesticide/PCB and
PAH
Lipid AnalysisPriority Pollutant
MetalsCyanide
Grand Total
30
15
33
2
58
10
60
30
36
4
113
15
90
45
69
6171
(a) Large amounts of sample mass may be difficult to obtain for selected biologicalsamples (eg: terrestrial insects, aquatic plants, and benthos). Under thesecircumstances QA-QC requirements and/or analytes of interest may have to bereduced.
(b) Based on separate samples for matrix spike (MS) and matrix spike duplicate (MSD).One MS and MSD are required for each case of field samples received by thelaboratory or each 20 field samples in a case.
as sampling the most representative components and will therefore best support riskassessment. Should significant or substantial risks to ecological receptors be indicated byfindings of the initial assessment, further focused sampling could potentially be conducted forspecific receptors and/or compounds. The fundamental criterion for determining the need toconduct additional body burden sampling is the adequacy of the Stage III risk assessment forrisk characterization and risk-management decision-making. If the uncertainty of Stage IIIfindings is adequately low and the conclusions technically sound, additional measurementswill not be required. If residual uncertainty is high, additional focused study may benecessary and would be discussed with regulators as appropriate.
The analytical methods listed in Table 5-1 require certain sample sizes to achieve detectionlimits and perform necessary QA-QC. Ideal sample size requirements are shown in Table 5-2 for each type of analyte. Given the matrix to be investigated for these analyses, it canoccasionally be difficult to obtain the required sample size. This is particularly true forsmall organisms such as terrestrial insects and benthos. During the field operations of thistask EA will attempt to obtain the tissue masses listed in Table 5-2, and in instances wherethis may not be possible QA-QC requirements and/or analytes of interest may have to bereduced. The decisions of which QA-QC requirements or analytes of interest to be reducedwill be made, if necessary, using best professional judgement based on knowledge of the site,analytical methods, and availability of surrogate information.
Terrestrial plants, small mammals, and insects will be targeted for collection from the 9floodplairi areas along the mainstem of Fields Brook as well as from the two backgroundlocations (Figure 5-1). The first background location (BK1) is adjacent to Red Brook on thesouth side of Wade Avenue. The second background location (BK2) is adjacent to the eastbranch of Whitman Creek immediately south of the railroad tracks. These locations wereselected to match the sampling transects which will be used for the remainder of the SQDIPhase II sampling so that the data overlap will support all assessments. The backgroundlocations indicated in the Figure may be shifted somewhat during field activities in order tooptimize the match between habitat types at site and background locations. During field
5-12
activities, any conditions which are noted that might tend to bias the adequacy of thesetributaries as background locations (e.g., NPDES discharges, landfills, etc.) will be notedand investigated.
Aquatic plants, benthos, and fish will be targeted for sampling from the ponded areas alongReach 8-2 and from background locations if possible (as they may form importantcomponents of the diets of ROC on the site itself for organisms which forage both on and offsite). Attempts will be made at all locations to obtain reptile and/or amphibian specimens.Should any particular category of receptor not be available for collection during field work(for example, sufficient insect tissue may not be available from some reaches of thewatershed), the sample will be shifted to a surrogate in a similar category (if available) sothat the total number of samples (but not necessarily the targeted receptor categories) will betaken for analysis if possible. Thus, the target categories of tissue are goals for which bestefforts will be made, but the total number of samples may be met by shifting, if possible, thedistribution of samples among similar categories. A summary of proposed biological samplesis shown in Table 5-3.
Since holding times appropriate for tissue analyses are not rigidly defined, the holding timesappropriate for soils and sediments have been substituted for this study. These times arepresented for each biota group below.
Mammals
Numerous species of mammals potentially inhabit the Fields Brook area. Small mammalswhich may serve as food for owls and other carnivores include white-footed mice, deer mice,voles, shrews, and other taxa. Attempts to capture specimens of small mammals will bemade at all 9 floodplain stations and both background stations in accordance with the SOPpresented in EA's supplement to the project QAPP. Due to the variable nature of anticipatedexposures of these organisms to contaminants, a sufficient number of specimens will beobtained to provide three separate samples from each station for analysis for a total of 33
5-13
TABLE 5-3. Summary of planned Phase II biota sampling. Reaches identified as BK1 and BK2are background samples. The abbreviation "Dups" refers to duplicate samples.Total level of effort for sampling of reptiles and amphibians will berestricted to five samples from the site for model validation purposes.
TerrestrialReach Plants
2-13-14-15-15-26-18-18-2 (pond)13-2BK1BK2Dups
Total
11111111111—
11
AquaticPlants
.
-1
11—
3
SmallMammals
33333333333—
33
Fish
-
-1
11—
3
Insects
11111111111—
11
Benthos
-
—1
11—
3
Total tissue samples = 6 4 + 5 reptile and/or amphibian = 69
samples. Since individual specimens may not posses sufficient tissue for analysis, tissuefrom several individuals may be composited in the field but composites will be made onlywithin species and only if all unless absolutely necessary.
Specimens will be collected using trapping techniques appropriate to the species identified.Techniques will be chosen by the field investigator and may include\ •••'man or otherHvetraps, Museum special or other snap traps, or other suitable gear. A sufficient number oftraps will be baited and set at each location to ensure adequate coverage of the area. Trapswill be monitored daily and only sufficient specimens will be retained to meet samplingrequirements. Tentative identification will be made in the field by a trained biologist andlimited screening will be performed on-site to ensure that samples retained for analysis arerepresentative of the biota of the area. This information will be recorded in field logs alongwith statements regarding any screening procedures undertaken.
Traps will be baited and set at each of the designated sampling locations. After traps arechecked daily, animals will be removed and identified. If the field investigator determinesthat the specimens are appropriate for analysis, they will be killed if necessary, and wrappedin aluminum foil (dull side toward sample) which has been rinsed with reagent grade acetoneand pesticide grade hexane. The wrapped sample will be placed in a clean plastic bag,labeled, and stored on ice in the field pending shipment to the laboratory for whole bodytissue analysis. Samples will be preserved on dry ice for shipment and will be placed in afreezer upon receipt at the laboratory.
Preliminary field identifications, numbers of animals captured, site information, and otherpertinent notes will be recorded in a field notebook for each specimen regardless of whetherthe sample was retained for analysis or released. Each specimen retained for analysis will beassigned a sample tracking number which will be used to correlate tissue analysis data withfield data and observations. Wet weight will be recorded at the laboratory for all specimensanalyzed.
5-14
DISCUSSION OF FIELDS BROOK
PRP ORGANIZATION APPROACH TO
WETLANDS AND FLOODPLAMS
Prepared by:
EA Engineering, Science and Technology15 Loveton Circle
Sparks MD 21152
Prepared for:
Fields Brook PRP Organization
Samples will be labeled and stored on ice after capture, and frozen at the end of each sampleday for delivery to the receiving laboratory. Holding times for samples treated in thismanner are 14 days from sample collection and will be adhered to for all samples.
Fish
Fish tissue analysis will be conducted for the purpose of evaluating potential risks topiscivorous birds and for fish as distinct receptors. The area to be sampled is upstream ofthe areas of concern, therefore observed concentrations will serve as "background"contributions to ROC diets and are required for complete baseline risk assessment. Sincecontaminant sources in the mainstem of Fields Brook will be remediated and concentrationsof COCs in fish in these locations are assumed to be essentially zero (as contributed from theBrook itself) following remediation, fish will not be collected from these locations. Baselinerisks associated with fish from Reach 8-2 (ponded area) will be evaluated by obtainingspecimens of fish as available to characterize dietary contribution of contaminants of COCsto receptors. In addition, attempts will be made to obtain fish tissues from the twobackground locations to determine if concentrations observed on-site are significantlyelevated. Key fish taxa which potentially exist on-site include various centrarchids (bass andsunfish), cyprinids (shiners, dace and chubs), percids (perch and darters), and esocids(pickerel). Other taxa potentially present include suckers (catastomids) and catfish(ictalurids). Since individual items may possess insufficient mass for analytical purposes,balanced composites will be made in the field. Composites will be made up of individualsmatched by taxon as closely as possible. In all cases, should compositing be necessary, theindividual taxa comprising the composite and wet weights of each individual will berecorded. Fish will be collected using seines, dipnets, traps, angling, or electroshockingapparatus operated either from a boat or a backpack unit as is appropriate for specificlocation conditions.
Although electroshocking for fish has not been a useful technique at Fields Brook in the past,the areas of interest in this study are shallow water habitats which may allow use of a Coffelt
5-15
BP-1C backpack unit (or equivalent). This unit may be employed by the field crew whilewading in shallow areas on the site. In some areas it may be necessary to sample in deeperwater in order to obtain sufficient sample quantity for analysis. These areas may beelectrofished using either a shore-based electrofishing unit or an electrofishing boat. A pramor boat equipped with an Coffelt VVP-2c electrofishing unit (or equivalent) powered by a120 volt generator is used to sample deep areas. A pulsed direct current (DC) is runbetween hand-held anodes, and the pram or boat hull acts as the cathode. A more powerfulelectrofishing unit such as an electrofishing boat equipped with a Coffelt VVP-15 unit (orequivalent) powered by a 240 volt generator is another option. When in operation, pulseddirect current (DC) will pass between a boat-mounted anode and the boat hull (cathode).
All stunned fish will be collected in dipnets and held in buckets until sampling is complete.Only specimens which are appropriate for inclusion as food for water birds will be retained,other specimens will be released. Upon completion, specimens will be preliminarilyidentified and the identifications and lengths will be recorded in a field log book along withother pertinent information.
Each fish selected for tissue analysis will be weighed and measured, rinsed in site water andstunned with a sharp blow to the head. Immediately following stunning, whole-body sampleswill be wrapped in aluminum foil which has been acetone and hexane rinsed and the dull sideplaced toward the sample. Samples will be placed in water-tight plastic bags.
Samples will be labeled and stored on ice after capture, and frozen on dry ice at the end ofeach sample day for delivery to the receiving laboratory. Holding times for samples treatedin this manner are 14 days from sample collection and will be adhered to for all samples.
Aquatic and Terrestrial Plants
Portions of aquatic and terrestrial plants which may serve as dietary items for ROCs(including roots, etc. as determined appropriate by the field investigator relative to the
5-16
species in question) will be collected for tissue analysis. Appropriate aquatic plants (ifavailable) will be collected from Reach 8-2 and background locations. Particular attentionwill be given to collecting portions of these plants which serve as primary food items (e.g.,fruiting bodies, seeds, etc.). Potential aquatic species identified for inclusion are pondweeds(PQtomogeton sp.), naiads (Najas sp.), and possibly tapegrass (Vallisneria sp.) as a surrogatefor other species if required.
The perimeters of aquatic sites (e.g., ponds) will be visually inspected and selected species ofsubmerged aquatic vegetation (SAV) will be identified and collected. Above-sedimentportions of aquatic plants from deeper areas may be retrieved with a plant hook. Allinformation including date, station location, an assigned sample tracking number, preliminaryidentifications, general composition of sample, and other pertinent site and collectioninformation will be recorded in a field notebook.
Terrestrial plants which may serve as food for herbivores and omnivores (deer and rodents)will be sampled at all locations. Specific attention will be given to items which have a highfood quality such as seeds, twigs, flowerheads, fruits, nuts, young shoots, and otherappropriate browse items. Since individual items may posses insufficient mass for analyticalpurposes, balanced composites will be made in the field. General descriptions of collectedmaterials will be recorded in field logs. Samples will be wrapped in solvent cleanedaluminum foil, placed in plastic bags and stored on ice for storage and shipment to thelaboratory. Samples shipped to the laboratory will be placed on dry ice. Holding times forsamples treated in this manner are 14 days from sample collection and will be adhered to forall samples.
Terrestrial Insects
Insects which may compose portions of the diets of ROCs will be collected from all locationswhen available in accordance with the SOP presented in EA's supplement to the projectQAPP. Taxa which are appropriate for collection include butterflies, moths, beetles,
5-17
crickets, and grasshoppers, as well as others. Insects will be collected by hand, byinspection of vegetation and litter, and with nets. Since individual items may possessinsufficient mass for analytical purposes, balanced composites will be made in the field. Ageneral description of the composition of each sample will be recorded in field logs.Composites will be made up of individuals matched taxonomically as closely as possible.
Samples will be wrapped in solvent cleaned aluminum foil, placed in clean plastic bags,labeled, and stored on ice after collection, and frozen daily for storage and delivery to thereceiving laboratory. Samples shipped to the laboratory will be packed in dry ice. Holdingtimes for samples treated in this manner are 14 days from sample collection and will beadhered to for all samples.
Benthic Macroinvertebrates
Benthic macroinvertebrates (benthos) which may serve as dietary items for some ROCs willbe collected as available from appropriate areas of the site. Principally targeted will becrayfish since they are important dietary items when present and sice they have sufficientmass for laboratory analysis of contaminant concentrations once composited. Collections willbe performed in accordance with the SOP presented in EA's supplement to the projectQAPP. Since contaminant sources in the mainstem of Fields Brook will be remediated andbecause these areas are not appropriate habitats for organisms which consume benthos (e.g.,water bird), benthos will not be collected from these locations. Baseline risks associatedwith benthos from Reach 8-2 (ponded area) will be evaluated by obtaining sufficientspecimens (if possible) to characterize dietary contribution of COCs to receptors. Inaddition, attempts will be made to obtain benthos from the two background locations todetermine if concentrations observed on-site are significantly elevated.
Aquatic invertebrates including insects, snails, crayfish, etc. will be collected by hand, byuse of dip nets, by traps or by remote gear (e.g. Eckman dredge or Ponar grab). Since theinvertebrates of principle interest are those in locations easily accessed by water fowl,
5-18
sampling will focus on these areas (primarily with dip nets). Dredge or grab sampling willbe used as a supplement to the dip net technique so that larger quantities of aquatic insectscan be obtained from each location. Samples obtained in this manner will be sieved on-site,or hand sorted (depending on specimen size and sample matrix), labeled and stored in cleanglass jars or plastic bags, stored in coolers at 4 degrees Celsius, packed in dry ice, and
••:'• Anped to the laboratory for analysis. Pertinent information including preliminaryidentifications, general sample composition, and site and collecting information will berecorded in the field log book.
Reptiles and Amphibians
Attempts will be made to collect reptiles and/or amphibians from all locations includingbackground areas. Probability of obtaining many specimens of these organisms is low.However, specimens which are obtained will serve as valuable benchmarks for riskassessment and every attempt will be made to locate sufficient organisms to serve for thesepurposes. Due to the potential health hazards related to handling of poisonous reptiles, onlyproperly equipped, qualified field biologists will engage in this activity.
Investigations will take place in and around leaf litter, logs, branches, and other suitableamphibian and reptile habitats. Snakes will be collected by hand, stored in cloth sacks andkilled by freezing. Each specimen will be transferred to a plastic bag and labeled. Notesincluding preliminary species identifications, numbers of organisms, and other pertinent siteand collection information will be recorded in a field notebook. Each specimen retained foranalysis will be assigned a sample tracking number which will be used to correlate tissueanalysis data with field data and observations.
Samples will be wrapped in solvent rinsed aluminum foil, placed in plastic bags, labeled,held in coolers and frozen daily for storage and delivery to the receiving laboratory. Holdingtimes for samples treated in this manner are 14 days from sample collection and will beadhered to for all samples.
5-19
5.3.1.4 Benthic Community Structure Analysis
Benthic community structure will be assessed with methods appropriate to quantitativeevaluation of freshwater soft-bottom ecosystems. Quantitative grab samples (e.g., "petiteponar" or other suitable devices) will be deployed from a boat or from shore as conditionspermit. Samples will be taken at each location until the jaws of the grab close and acomplete sample is obtained. If this is impossible at a particular location due to bottomstructure, the sample site will be moved nearby. Samples on board will be storedtemporarily in plastic trays or buckets and kept cool. On shore or at nearby facilities,samples will be handled and preserved. We anticipate sampling 3 locations in the pondedarea of reach 8, with triplicate samples taken at one location. No suitable reference area wasdetermined for comparison with this ponded area.
Samples will be washed gently through 0.5 mm mesh sieves and contents preserved in 10%buffered formalin with rose bengal. Samples will be returned to the laboratory forenumeration and identification to lowest practical taxon. Data will be analyzed graphicallyand statistically, employing parametric and non-parametric methods as appropriate.
Although the procedures, equipment, and objectives of benthic analytical processing asdetailed in OEPA (1989) differ substantially from those outlined here (for example, OEPA1989 emphasizes artificial substrate colonization sampling rather than grab samples)procedures for splitting, sorting, and handling samples will follow those in OEPA as closelyas possible consistent with project objectives.
5.3.1.5 Wetlands Habitat Evaluation
We propose to use the Fish and Wildlife Service's Habitat Evaluation Procedure (HEP) (U.S.Fish and Wildlife 1976) to evaluate wetland habitat present and its value for key species ofconcern. The purpose of this evaluation is to support ROC selection by providingquantitative information necessary to determine if candidate ROCs would be found in the
5-20
area. If necessary habitat components are absent, the candidate ROC may be supplanted withanother which is more likely to occur on the site because its habitat requirements are met.Specific species targeted for HEP evaluation were selected to genetically categorize thepreliminary food-web model (Figure 4-5) in order to support the ROC selection process.Representative taxa were selected to categorize habitat quality for the following receptorcategories: - ,,
Receptor Category Representative Species____
Predator (mammal) Mink (Mustela vison)Predator (raptor) Barred owl (Strix varia)Omnivorous Mammal No appropriate HEP species data availableLarge Herbivorous Mammal Whitetail deer (Odocoileus virginanus)Small Herbivorous Mammal Eastern cottontail (Sylvilagus floridanus)Waterfowl Wood duck (Aix sponsa)
The HEP models will establish existing habitat quality for this generic set of species based onselected field measurements of characteristics known to be important for these species (e.g.,presence of pools, vegetation type). Optimal habitat conditions are those conditions normallyassociated with the highest potential densities of the species of concern. The results fromthis effort will support final ROC selection during Stages II and III (Section 4.2.2.2). WhileHEP can be conducted on a large number of species, we will examine these genericcategories for this study in order to characterize habitat in a manner sufficient to supportfinal ROC selection. Two locations in each section of the floodplain (upper, middle, lower;Figure 5-1) will be evaluated under HEP. HEP models will be further supported with theWetlands Evaluation Technique (WET; U.S. Army Corps of Engineers). It should be notedthat, as stated in WET documentation (ACOE 1991; page 3 of introduction), "...[WET] isuseful as a screening tool to decide whether or not one should resort to more quantitativemethods such as the Habitat Evaluation Procedure (HEP)...", and as such, HEP informationwill be used by preference whenever possible.
5-21
5.3.1.6 Toxicity Studies
The purpose of evaluation of sediments in the Fields Brook floodplain is to determine if in-place materials are toxic to biota with which they are in intimate contact. Because bulkchemical analyses cannot address the issue of availability of contaminants for biologicaluptake (bioavailability), and because bioavailability is a critical factor cc ' Hing risk, thesestudies will provide the information necessary for translation of chemical analyses into riskevaluations at the base of the food web. Toxicity studies will be performed in accordancewith the SOP presented in EA's supplement to the project QAPP.
Sufficient soil will be collected from each site to provide 6 to 8 kilograms for uptake studies.Soil sampling will be conducted in accordance with the SOP presented in EA's supplement tothe project QAPP. These soils will be collected from areas which will be characterized forCOCs during other Phase II SQDI activities conducted by WCC. In addition, these soils willbe collected from the same locations as SQDI Phase II surficial soil samples (one pertransect) so that each tested sample is completely characterized. Additionalchemical/physical parameters which may control COC bioavailibility, specifically, pH, totalorganic carbon (TOC) content, moisture content, cation exchange capacity (CEC), grain size,and clay content will also be measured. Standard operating procedures for this assessmentand for non-CLP 3/90 listed above are presented in Chapter 4 of EA's supplement to theproject QAPP.
Because areas of Reach 4 have been flooded by recent beaver activity, an additional suite ofthree toxicity/bioaccumulation tests is proposed to determine bioavailability and toxicity offormer floodplain sediments in this area. Since collection of aquatic biota would beinfluenced by the Brook itself (a separate OU), these toxicity tests are the best way ofdetermining the in-situ risks associated with floodplain sediments. Data will be bothevaluated directly (toxicity) and will be used as input to the ecological risk assessment food-web model to evaluate any potential risks presented by the floodplain materials to the Brookand to biota in the surrounding area.
5-22
Worms will be acclimated to laboratory conditions. A preliminary study will be conductedof worm survival to ensure that test individuals are in adequate health to meet the objectivesof the test. Sufficient individual worms will be stocked to provide individuals necessary tomeet tissue mass requirements for detection limits for the samples taken from the floodplain(Section 2.3 of EA's supplement to the project QAPP). Biomass from replicate exposureswill be composited to meet thfc mass requirement. Background locations will be evaluatedfor survival only since bioaccumuiation factors from these locations are not required forfood-web modeling. Observations will be made throughout the study on individual conditionand mortality. In addition, earthworms will be sacrificed at the conclusion of each test andtissues will be analyzed for COC content following procedures presented in Section 2.3 ofEA's supplement to the project QAPP. Tissue mass required for these analyses are the sameas those presented in Section 2.3 of EA's supplement to the project QAPP. Referencetoxicant tests will be conducted (at least one per batch) according to standard procedures.
We anticipate conducting earthworm toxicity tests with soils from 3 locations within theFields Brook floodplain (one each from the upper, middle, and lower floodplain; Figure 5-1),and from 2 reference locations in addition to the newly proposed tests from the now floodedReach 4 area. Locations will be determined by coordination with other Phase II SQDIsampling activities to ensure co-location of samples for toxicological and analyticalevaluation.
5.3.1.7 Pitfall Traps
To evaluate wetland infaunal communities, we will employ pitfall trapping techniques.Pitfall traps are containers buried to ground level, covered loosely to keep .moisture out, andpartially filled with non-evaporating preservative such as ethylene glycol. Pitfall traps catcha key component of the soil fauna, that which uses the soil-litter interface (EA undated), andthus provide an excellent measure of potential biotic impacts of contaminants.
5-23
We anticipate placing pitfall traps at 10 to 15 locations in the Fields Brook floodplain withtriplicate traps at each location. Traps will be placed at two reference locations withtriplicate traps at both. Pitfall trapping will be conducted in accordance with the SOPpresented in EA's supplement to the project QAPP. Samples will be returned to thelaboratory for enumeration and identification to lowest possible taxon. Data will be analyzedby comparative z ~~*ics, employing parametric and nonparametric methods as appropriate.
5.3.2 Baseline Ecological Risk Assessment
As discussed in the introduction to this section, ecological risk evaluation is being driven byspecific technical and regulatory issues. To address these issues, quantitative ecological riskmodeling will be conducted on particular receptors of interest and focused on particularecological processes. Bioavailability and trophic transfer will be key issues in quantifyingpotential risk to ecological receptors via possible food web interactions. To address theseissues, the tasks outlined in the introduction of this section will be conducted in compliancewith agency guidance (EPA 1989a & b). This guidance describes eight subtasks which makeup a complete ecological risk assessment:
1. specify objectives2. define scope3. describe site and study area4. describe contaminants of concern5. characterize exposure6. characterize risk or threat7. apply risk estimates to site assessment/remediation process8. describe assessment conclusions and limitations.
A generalized flow chart of the proposed risk characterization process is presented in Figure5-2. Each of the subtasks listed above are discussed in greater detail below.
5-24
Compile siteInventories
Identify ROCsand Surrogates
Quantify COCsin Tissue and
Environmental Media
Compile FoodWeb Model
Identify ToxicityEndpoints (TRVs)
Compare TissueConcentrations
to TRVsCompare Doses
to TRVs
QuantifyProjected
RisksQuantify
Extant Risks
Evaluate RiskManagement andRisk-of-remedy
Figure 5-2. Generalized approach to Fields Brook flood plainbiota investigation.
5.3.2.1 Objectives
General objectives for this investigation are to characterize potential receptors, characterizepotential exposure, characterize potential risks, and evaluate risks associated with variousremedial options. Specific objectives include determining spatial distributions of biota bodyburdens, determining uptake and exposure mechanisms, determining presence anddistribution of receptors in the watershed, and quantifying trophic transfer of contaminantsand bioavailability and bioaccessibility. As described in this EIWP, these objectives will bemet by combining existing information with additional field studies to characterize nature andextent of contamination and receptor distribution, and with quantitative risk modeling toevaluate threats to key receptors.
5.3.2.2 Scope
The scope of the baseline ecological risk assessment will largely depend on Stage I and StageII findings. The spatial scope of study is focused on the Fields Brook floodplain. Becausecertain receptors may travel beyond the bounds of the floodplain (for example, migratorybirds, raptors, fish and large reptiles), the scope will be further defined as studies proceed.
5.3.2.3 Site and Study Area Description
Comprehensive descriptions of the site and study area are presented in the final remedialinvestigation report prepared by CH2MHill (1985), and have been summarized in Section 2.0of this EIWP.
5-25
5.3.2.4 Contaminants of Concern
Existing information on COCs in floodplain soil and sediment have been summarized inTable 4-1. Previous analyses have shown the following as potential COCs for the FieldsBrook floodplain:
Metals: arsenic, cadmium, copper, lead, mercury, selenium, thallium
Volatile Organics: chloroform, 1,1-dichloroethylene, 1,1,2,2,-tetrachloroethane,1,1,2-trichloroethane, tetrachloroethylene, trichloroethylene,vinyl chloride
Semivolatile Organics: benzo(a)pyrene, hexachlorobenzene, hexachlorobutadiene,hexachloroethane
Pesticides/PCBs: a-hexachlorocyclohexane (BHC), 7-hexachlorocyclohexane(lindane), heptachlor, Aroclor 1242, 1254, 1260.
Of these, arsenic, mercury, hexachlorobenzene, benzo(a)pyrene, and PCB were the mostcommon. Most of these contaminants have been detected in 20 surface (0-6 inches)floodplain samples were taken during Phase I of the SQDI. Further discussion of proposedscreening of contaminants of concern is presented in Section 4.2.2.2. This COC evaluationwill account for environmental behavior, concentration, occurrence, and toxicity, and willspecifically address contaminants that have potential impact to biota.
5.3.2.5 Exposure Characterization
Generally, for sites at which ecological issues play key roles in developing and evaluatingrisk management options, exposure assessment is the most technically demandinginvestigation subtask. Receptor exposure is controlled by a complex of factors which include
5-26
presence, distribution, chemical behavior, food web composition, seasonality, and habitat-type among many other factors. For this environmental assessment, exposure analysis willserve as the basis for all quantitative risk modeling. Exposure will be modeled on the basisof both site specific (receptor surveys, contaminant assessment) and general (trophicstructure, ecological processes) information. Exposure models will account forbioaccessibility and bioavailability of contamiiu. as well as other important ecologicalprocesses. The product of the modeling effort will be compared to toxicity reference values(TRVs) for evaluation of risk potentials as described in below.
5.3.2.6 Risk Characterization
Risk characterization will be conducted in accordance with EPA guidance and strategicupdates (U.S. EPA 1988b, 1989, 1992a,b,c), and will address the probability, magnitude,and temporal nature of adverse effects. In addition, this characterization will be spatiallyconstrained to define risks associated with particular areas of the watershed. This assessmentwill provide the basis for rational, defensible decision-making regarding risk managementactivities.
5.3.2.7 Application
Under applicable guidance, risk estimates will be compared with existing ARARs and To BeConsidered criteria (TBCs), and the basis for such comparisons will be thoroughlydocumented and clearly presented. ARARs and TBCs are generally lacking for soil andsediment or biota, but are usually found for surface water (e.g., MCLs or Water QualityCriteria). An approach to applying study results to responsive decision-making will bedeveloped. This approach and resulting recommendations will be fully documented andpresented for discussion and use for risk management decisions.
5-27
5.3.2.8 Conclusions and Recommendations
Conclusions from each subtask of the ecological risk assessment will be developed in such amanner that the information from each supports and complements others. This informationwill be synthesized into a technically complete evaluation of receptors potentially at risk,
.contaminant nature and distribution, exposure, toxicity, and projection of future conditions.Variability around quantitative estimates, uncertainties surrounding qualitative estimates andcomprehensive conclusions, and the implications of each for application of study results willbe thoroughly documented. Conclusions and recommendations resulting from thisenvironmental assessment will support clear, technically defensible, well documentedevaluation of site related risks and rational evaluation of management alternatives.
5.3.2.9 Exposure Evaluation Model
The risk assessment model (Section 5.3) will be structured as a food web and trophic transfermodel based on results of ROC and COC selection. Because it is necessary to account fordietary items of all of the anticipated ROCs, several dietary categories will be investigated.Principle dietary items for the anticipated ROCs include terrestrial plants (browse for deerand lower trophic levels such as mice), aquatic plants, benthos, and fish (food for waterbirds), terrestrial insects (such as grasshoppers and ground beetles as food for kestrels), andsmall mammals (such as field mice as food for owls). Since sediment remediation is alreadyplanned for large portions of the main-stem of Fields Brook, aquatic plant and benthossamples will be collected only in the marsh area along Reach 8-2 and background locations.Attempts will be made to obtain reptiles and amphibians (such as snakes, frogs, and toads)for the purpose of verifying extrapolation of risks to ROCs. Since the majority of reptilesand amphibians are carnivorous, feeding at essentially the same trophic level as raptors,evaluation of concentration of COCs in these organisms allows validation of extrapolations tothese unsampled compartments.
5-28
In the event that tissue samples are not available for some areas (e.g., aquatic plants andbenthos from background locations), other techniques such as establishment and use ofbioaccumulation factors relative to sediment or floodplain concentrations for other areas orliterature values will be used to supplement modeling procedures. The reference sedimentconcentrations that will be used in the event that this circumstance should arise are thosecollected in the upper watershed area during Phase I and Phase II activities.
Risks of exposure of ROCs to COCs will be evaluated by calculating daily intake of COCsand comparing these values to toxicity reference values (TRVs). Daily dietary intakes willbe calculated as follows:
1) Concentrations of COCs will be identified in dietary items for each ROC;2) Mean dietary concentrations of COCs for each ROC will be calculated by multiplying
mean COC concentration in each dietary item by fraction of diet (from literaturesources) and summing all fractions;
3) Portion of diet obtained from the Fields Brook site based on foraging range of ROCswill be estimated from literature sources;
4) Daily COC dose will be calculated by multiplying food consumption rate (fromliterature sources) by portion of diet from site and the mean dietary concentration ofCOC.
The products of this exercise will be identification of regions in which COCs are sufficientlybioavailable and bioaccessible to ROCs to warrant further concern during risk managementactivities.
5.3.2.10 Toxicity Reference Values (TRVs)
Toxicity reference values (TRVs) are benchmarks of COC exposure (dose) or body burdenabove which adverse chronic effects may be observed and below which adverse chronic
5-29
effects are not anticipated. TRVs are necessary for evaluation of potential adverse effects ofCOCs to ROCs in this process for: 1) screening of COCs (derivation of toxic quotients) on atissue concentration basis, 2) evaluation of baseline risks (doses to ROCs), and 3) evaluationof projected risks. These TRVs will be developed using a technique adapted from Lewis etal. (1990) which uses the primary literature as an information source and adjusts endpointsfor quality. This technique provides scientifically defensible methodologies for extrapolationand application of no observed adverse effects levels (NOAELs) across taxa and evencompounds when literature-based information on toxic effects is limited as is likely to be thecase for the majority of COCs and ROCs at the Fields Brook site. Since TRVs are requiredon a tissue concentration basis for screening and model validation, and on a dose basis forbaseline risk characterization, both will be developed using this technique.
5.4 DATA MANAGEMENT
An RI typically generates an extensive amount of information, the quality and validity ofwhich must be consistently well documented because this information will be used to supportremedy selection decisions and legal or cost recovery actions. Therefore, field sampling andanalytical procedures for the acquisition and compilation of field and laboratory data aresubject to data management procedures.
Data management procedures include Data Quality Objectives (Chapter 4); field samplingdocumentation and recordkeeping (Section 6.3); sample management and tracking (Section6.4); and document control and inventory. These procedures, with the exception ofdocument control and inventory, are described in more detail elsewhere in this document.
5.4.1 Document Control and Inventory
Since Fields Brook is an NPL-listed sites, maintenance of the Administrative Record is ofprimary importance. The Administrative Record is the legally binding record of
5-30
investigation and response activities for the sites. As such, it is essential that all projectactivities be properly recorded as part of the Administrative Record.
For this study of the Fields Brook floodplain, the Work Plans, results of Stage I, II, and IIIsampling and analysis, the ecological risk modeling, the contamination assessment, theecological risk assessments; the floodplain investigation Stage I and III reports, ' allrelevant project correspondence will become part of the Administrative Record for this site.Sample results will be managed in a standardized form to promote easy reporting of data inthe site characterization report. Precautions will be taken in the analysis and storage of thedata collected during site characterization to prevent the introduction of errors or the loss ormisinterpretation of data. A document inventory and filing system will be set up on the basisof serially numbered documents. Further discussion on the importance of the AdministrativeRecord is addressed in U.S. EPA (1988).
5-31
6. SAMPLE HANDLING
6.1 SAMPLE NUMBERING SYSTEM
A sample numbering system has been developed in cooperation with WCC and will be usedto ??$% tracking, retrieval, cross-referencing of sample information, and consistency with
'^ - vjifn'.the established SQDI sample numbering system.
Each sample submitted for chemical analysis will be assigned a unique sample identificationnumber. The sample identification number will consist of 4 parts:
• Sample matrix code:BS Bioaccessable Soil and Sediment SampleFW Floodplain Ponded Area Surface Water SampleBI Biological Sample
• Sample Location:1. A four digit number will follow the sample matrix code for abiotic
samples and a six digit number will be used for biota. The first twodigits identify the reach, the third digit the subreach, and (in the case ofbiological samples only) the last three digits the organism or compositenumber.
2. Single letter "D" for duplicate sample, or "S" for sample.3. The number "3" will follow to identify the sampling event as the
ecological risk characterization.
An example of a sample identification number follows:
BI052001S3 This number indicates the sample is biological, collected in Reach 05,subreach 2, and because it is a biological sample, it is the first (001) organism
6-1
(or composite) collected at this location. It is a "sample" (not a duplicate) andis associated with the ecological risk characterization.
6.2 ANALYTICAL PARAMETERS AND METHODS
The generic list of analytical parameters for the Fields Brook floodplain study is provided inTables 4-2 and 5-1 under the specific analytical categories of Target Compound List (TCL)volatiles, TCL semivolatiles, metals (Target Analyte List (TAL) for surface water, PriorityPollutants (PP) for biota and soil and sediment) and other associated physical parameters.Analytical methods are described in greater detail in EA's supplement to the project QAPP.
6.3 SAMPLING PRINCIPLES
Proper sample collection is one of the most important parts of an environmental project.Without proper sample collection techniques, the results that are obtained from the associatedanalyses will be neither useful nor valid, even though the analytical technique used may bevery precise and accurate.
The variety of sampling locations and associated conditions which exist at the sampling sitewill require that some judgment be made regarding the implementation of the methodologynoted in the subsequent paragraphs. These judgments will be made by qualified personnelworking from the SOPs presented in EA's supplement to the project QAPP and will be basedon prior experience with representative samples previously analyzed and data from othersources concerning the sampling site.
Although each sampling location will require some special attention, depending upon itscomplexity, there are some basic requirements and precautions which will be generallyapplicable to the various sample types. Some of these are listed below.
6-2
6.3.1 Sampling Equipment
6.3.1.1 Water .Samplers
1. Clean with a non-phosphate laboratory detergent such as Alquinox or Liquinoxuwf.7 a brush as necessary to remove paniculate matter and surface films.
2. Wash and rinse with tap water.3. Rinse with 0.1NHCL.4. Rinse with tap water.5. Rinse with methanol.6. Pesticide grade hexane rinse.7. Rinse with methanol.8. Double rinse with laboratory-grade deionized/distilled water.9. Airoroven(125°C)dry.10. Collect and store rinsate for disposal.
6.3.1.2 Excavation Equipment and Soil Samplers
1. Clean with tap water and laboratory detergent such as Alquinox or Liquinoxusing a brush if necessary to remove paniculate matter and surface films.
2. Rinse with 0.1NHCL.3. Rinse with tap water.4. Rinse with methanol.5. Rinse with pesticide grade hexane.6. Rinse with methanol.7. Double rinse with laboratory-grade deionized/distilled water.8. Air dry.9. Wrap with aluminum foil, if appropriate, to prevent contamination if
equipment is going to be stored or transported.10. Collect and store rinsate for disposal.
6-3
6.3.1.3 Biota Samplers
1. Clean equipment as appropriate (i.e., wash seines and nets free of particles;scrub and rinse benthic grabs thoroughly; backwash and rinse sieves).
2. Between sampling points, wash all equipment free of particles with tap orambient water.
6.3.2 Sample Container Preparation
All sample containers will be prepared by the protocol noted below in order to minimizesample contamination.
1. Wash with nonphosphate laboratory detergent such as Alquinox or Liquinoxand hot water.
2. Rinse three times with tap water.3. Rinse with 1:1 nitric acid (use caution "when performing this step).4. Rinse well with deionized water. Sample containers should be totally filled
and over-filled at least three times.5. For bottles used for extractable organics:
a. Rinse with methylene chloride.b. Rinse will with organic free water. Sample containers should be totally
filled and over-filled four times.6. Dry in a glassware oven (no organic contaminants) at 125°C. Allow to cool.7. Teflon liners for the bottle caps should be carried through the same procedure.
Polyseal liners and bottle caps should not be rinsed with nitric acid and shouldbe air dried, not dried at 125°C.
Because of the stringent requirements for trace analysis, only bottles prepared as above are tobe used. In addition, these sample containers should be handled, stored, and utilized tominimize the chances of contamination by outside sources.
6-4
The selection of the appropriate container is dependent upon the analytes of interest. Alisting of required containers is included in Table II of 40 CFR 136.3.
6.3.3 Reagents
Only reagents and chemicals certified to be "reagent grade" or better, are to be used for ...environmental projects. For metal preservation and analysis, Ultrex nitric acid or equivalentis the reagent of choice. Reagents for organic contamination analysis, such as methylenechloride and ethyl ether, should be analyzed to determine trace organic content. Chemicalreagents should be handled, stored, and utilized to minimize the chances of contamination byoutside sources.
6.3.4 Sample Preservation
Since very few analyses will be performed on samples immediately after collection, it isimportant to prepare for and implement appropriate preservation techniques for the varioussample matrices. Since the addition of chemicals as preservatives and changing the physicalcondition of the sample, such as cooling to 4°C, has some effect on the sample itself, it isimportant to implement analyses as soon as possible. The appropriate preservationtechniques are specified for each of the various specific tests. When chemical preservativesare used, they should be added to the sample bottle initially so that all portions of the sampleare preserved as soon as collected (as specified in the attached Quality Assurance Manual forEA Laboratories).
6.3.5 Collection of the Sample
When sampling, it is important to randomly collect enough material from the samplingsource such that a representative sample is obtained. Liquids with no suspended solidsgenerally require only small volumes of material to meet this requirement. On the otherhand, solids or semi- solids containing some liquid may require the collection of more
6-5
material to fully represent the condition at the source. Some judgment must be made atindividual collection sites to ensure that this objective is met. Under any circumstances, theSOPs presented in EA's supplement to the project QAPP should be consulted during allactivities.
Compromises on sample size may have to be exercised when practical limr -*"-*ns such assize of sample container and the need for storage and transportation are involved. Ingeneral, the collector of the sample has the responsibility for its validity. In those caseswhere a sample collector is unsure of the proper method for collection, he is required toconsult with the site supervisor or appropriate SOPs.
6.4 SAMPLE CUSTODY AND SHIPMENT
Accountability for a sample begins when the sample is taken from its natural environment.A bound field logbook will be maintained to record the acquisition of each sample. Entriesmust be made in waterproof ink. Only samples for one project site are entered in a givenlogbook. The logbook will contain information to distinguish each sample from any othersample. This information will include:
• Project name for which sampling is being conducted• Unique, sequential sample number• Matrix being sampled (ground water, soil, etc.)• Sample depth• Sampling date and time• Specific sampling location in sufficient detail to allow resampling at the same
location• Method of sampling• Preservation techniques, including filtration, as appropriate for separate sample
aliquots
6-6
• Analyte classes of interest• Significant observations made during the sampling process
• Results of any field measurements, such as temperature, conductivity, and pH• Printed name and signature of the person performing the sampling.
In addition to the sampling logbook, each sample will be unambiguously labeled inwaterproof ink with the following information:
• Site name• Unique, sequential sample number• Sampling date• Analysis type• Preservative added and any filtration accomplished
When samples are shipped to the laboratory under chain-of-custody, a copy of the logbookpages describing samples are also sent in the same shipping container. Entries will be n.adein the logbook noting date of shipment, number of shipping containers, samples sent, andcarrier.
If specified in the Site Health and Safety Plan or otherwise considered prudent, a separatesafety label will be prepared for each sample. In some instances a seal which lists samplenumber, date and time of sample collection, and signature of the sampler must be placed onthe lid of the sample bottle. This sample seal is to ensure that the sample is not tamperedwith during shipment. Figure 6-1 is a sample of a typical chain-of-custody form. Onechain-of-custody form will be completed for each day of sampling at each sampling location.The chain-of-custody form is to accompany the sample throughout the shipping and analyticalprocess. Each cooler will have a separate chain-of-custody.
6-7
T 1I <T>
O=TK.=36
R8o-1o.
T
*sIs
onTl '5
1
I'B
5
Dc
.£>
iifI
|
f3
fT)
O
•o
Gt
533
(T
if9-
i3
A
fi
fi
Holding Tim
M tor VO
A»Sam
ple Shipped by: (C
ircia)
Fed. Ex. Puro.
UPS
Other
Ait BW N
umber
Sam
pled
I/)
1
a
Dale/Tuna
1
J?
1i
Recerw
d by: (Signature)
- f
>: , . ' ,
r th rh
: tr
; • t r r ; ' : . " :iL
f
|
t
i-
i-k
L
h
—
~-
I
ir
ilL L
[. t i
f
, . .. p :
r
L
V-
ri-i
r
t-
i'
.t
-- • — --•
[h
L
" i
i
t
ih
i
\; j
. . . . . L...J „-;---,_ _
1 I . . . . i
'— r— *--- - i - - - - - - -.—-. --
•
-- f — --
5
rl3
Walerol
S*mp*fl kM
nnftcaDon(ID
And Matnx)
1 9 Chw
aciers
a
6
S«T
^» S
torage Loconon
PrD
fOC
I No
OU
JDN
IS
OlO
JJ
f
T T :
' ~So _
£
g
&
1
No. of Containers
:
EA
Uba
AcMM
onN
umber
Ram
ark-
-- -
Repora/D
eliverable* On»|f
iff?
ParB
mcle
n/M
eO
xxJ Num
bers lor Analysis*
!C
hain-of-Custody R
ecord
Shipment of samples will be in accordance with DOT Regulations described in 49 CFR 171and 49 CFR 172, and NEIC procedures (EPA-330). This is usually guaranteed air freight.If the nature of the samples precludes air shipment, the fastest motor freight is used.Samples are shipped, preserved, and cooled according to EPA protocols. Shipping schedulesare arranged to ensure sample processing within holding times specified for analyticalparameters. Shipping documents such as package registration are kept to record the shippingprocess and to serve as tracers.
Sample packing and shipping procedures are as follows:
• Secure sample jar lids.• Position jar in Ziploc bag so that labels can be read.• Line coolers with large heavy plastic garbage bag.• Place about 1 in. of absorbent packing material into bottom of garbage bag in
cooler.• Place jars in cooler and fill remaining volume of cooler with ice and packing
material.• Put paperwork in plastic bags and tape with masking tape to inside lid of
cooler.• Tape drain shut.• After acceptance by shipper, tape cooler completely around with strapping tape
at two locations. Secure lid by taping. Do not cover any labels.• Place laboratory address on top of cooler.• Put "This Side Up" labels and arrows on two sides.• Affix numbered custody seals on front right and back left of cooler. Cover
seals with wide, clear tape.• Ship sample via overnight carrier.
6-8
6.5 SAMPLE TRACKING
Upon completion of sample collection, logging, and preservation, the chain-of-custodyprocedures will be initiated. Because of the large amount of samples to be collected, sampletracking will start at the job site, where a spreadsheet will be updated daily after the samplesare logged, chain of custody completed, and samples prepared for shipping. Following thearrival of samples at the laboratories, the conditions of those samples shipped will beconfirmed (e.g., are any broken, improperly preserved?). Once the conditions of samplesare established, the sample spreadsheet will be updated again, if needed.
Stage III will have its own set of spreadsheets that summarize how many and what type ofbottle and preservatives are needed. Each field crew will be issued this information prior tosampling.
6-9
7. PROJECT SCHEDULE
The following project schedule is proposed for this EIWP:
Stage I - Human use characterization, floodplain ecosystem characterization, and sedimenttransport analysis.
1) Stage I ecological investigationworkplan submitted to USEPA - 1 October 1992
2) Agency approval - 1 November 1992
3) Human Use Evaluation . - 11-12 November 1992
4) Technical memorandum detailing - 15 March 1993Human Use results submitted toUSEPA
5) Remaining Stage I Tasks - 14-25 June 1993
6) Results of remaining Stage I - Submitted as part of Draft Final Reportactivities submitted to USEPA
Stage II - Analysis of existing data, preliminary risk characterization.
1) Data reduction begins - 1 November 1992
2) Workplan modifications begin - 1 April 1993
3) COC/ROC modeling begins - 1 May 1993
4) Modified workplan submitted - 21 May 1993
5) Data reduction ends - 30 June 1993
6) COC/ROC modeling ends - 15 October 1993
7) Technical memorandum on - 29 October 1993results submitted
7-1
Stage III - Focused field studies and baseline risk assessment.
1) Field work - 14-25 June 1993
2) Toxicity tests begin - 16-23 June 1993
3) Toxicity tests end - 7-14 July 1993
4) EA Laboratory results on water,and biota received
5) Additional field work
6) EA Laboratory results on water, sediment,and biota received
7) Preliminary risk assessment reportcompleted (internal review)
8) Preliminary risk assessment reportsubmitted to Agencies
9) Woodward Clyde Phase II datareceived
10) Baseline risk assessment reportcompleted* (internal review)
11) Baseline risk assessment reportsubmitted to Agencies"
* Assumes compatible electronic data transmittal
- 30 July 1993
- 27 September 1993
- 29 October 1993
- 3 January 1994
- 1 February 1994
- After QA/QC
- 60 days after receipt of verified data
- 30 days after receipt of comments
7-2
8. PROJECT MANAGEMENT8.1 GENERAL
Management of this project will require flexibility in organizing a team of scientific andengineering personnel and technical resources. The field investigation will employ pre-? -roved field procedures, sampling techniques, and analytical methods to accomplish datacollection objectives. Effective program organization will accommodate these requirementsfor both flexibility and consistency while maintaining a manageable degree of overallactivities. The following sections describe the roles of the various project management teammembers.
8.2 Program Manager Responsibilities
The Program Manager is responsible for oversight of all activities and provides direction andguidance to the Project Manager. The Program Manager is responsible for reviewing andapproving any and all submittals, including negotiation of rates, submission of fee proposals,negotiation of fee proposals and project scopes, selection of specialty subcontractors andpreparation of subcontractor agreements, monthly invoicing, and project status reports. TheProgram Manager ensures that all activities under this project are carried out in accordancewith contractual requirements and in accordance with the Corporate Hazardous WasteProgram Requirements.
8.3 Project Manager Responsibilities
The Project Manager is responsible for effective overall management of all project-relatedactivities. The Project Manager serves as the primary technical point of contact andcoordinates management of project subtasks. Specific responsibilities of the Project Managerinclude (1) management of all technical activities, (2) monitoring of schedules, labor
8-1
allocations, and plans, (3) management of all funds for labor and materials procurement, (4)review and administration of all work-order changes, (5) successful accomplishment of allcontractual obligations, including costs, schedules, and technical performance, (6)management of the Project Team toward unified, productive project accomplishment, and (7)technical leadership.
8.4 Quality Assurance Officer Responsibilities
The Quality Assurance (QA) Officer is responsible for overall quality assurance of all aspectsof the project. The QA Officer reports directly to the Consultant's President and has theauthority to audit all phases of all Corporate operations. The QA Officer oversees theCorporate Quality Assurance/Quality Control Program and is responsible for development ofStandard Operating Procedures (SOPs) related to analytical chemistry laboratory methods,field investigation and sampling programs, engineering design, and construction qualitycontrol. The QA Officer is responsible for development and oversight of the Sampling andAnalysis Plan and Quality Assurance Project Plan.
8.5 Health and Safety Officer Responsibilities
The Health and Safety Officer is responsible for development of project-related Health andSafety Plans. The Health and Safety Officer will assign site safety supervisors for variousphases of activities in accordance with the project-specific Health and Safety Plan. TheHealth -and Safety Officer will have the authority to temporarily halt any and all activitiesbased on identified health and safety concerns.
8-2
8.6 Field Activities Manager Responsibilities
The Field Activities Manager is responsible for direction and management of field samplingteams and assurance of quality data collection. The Field Activities Manager is responsiblefor implementation of the provisions of the Work Plan/Sampling and Analysis Plan, theQuality Assurance Project Plan, and the Site Health and Safety Plan during data collectionactivities, and for coordination with the analytical chemistry laboratory for sample handlingand transport.
8-3
9. REFERENCES
Army Corps of Engineers (ACOE). 1987. Corps of Engineers Delineation Manual.Technical Report Y-87-1, U.S. Army Engineer Waterways Experiment Station,Vicksburg, MS. 100 pp. plus appendices.
Army Corps of Engineers (ACOE). 1991. Wetland Evaluation Technique (WET). VolumeI: Literature Review and Evaluation Rationale. Technical Report WRP-DE-2, U.S.Army Engineer Waterways Experimeiv- .v "ion, Vicksburg, MS.
Ankley, G.T, G.L. Phipps, E.N. Leonard, D.A. Benoit, V.R. Mattson, P.A. Kosian, A.M.Cotter, J.R. Dierkes, D.J. Hansen, and J.D. Mahony. 1991. Acid-volatile sulfide asa factor mediating cadmium and nickel bioavailability in contaminated sediments.Environ. Toxicol. Chem. 10:1299-1307.
Hurt, W.H. and R.P. Grossenheider. 1980. A Field Guide to the Mammals. NationalAudubon Society, National Wildlife Federation, and Roger Tory Peterson Institute.289 pp.
Carlson, A.R., G.L. Phipps, V.R. Mattson, P.A. Kosian, and A.M. Cotter. 1991. The roleof acid-volatile sulfide in determining cadmium bioavailability and toxicity infreshwater sediments. Environ. Toxicol. Chem. 10:1309-1319.
Canter, L.W. 1977. Environmental Impact Assessment. McGraw Hill PublishingCompany, New York. pp. 220-232.
CH2MHill. 1985. Final remedial investigation report - Fields Brook Site, Ashtabula, Ohio.
Conant, R. 1975. A Field Guide to Reptiles and Amphibians. Houghton Mifflin Company,Boston, Mass. 429 pp.
Dean, B.V. and M.J. Nishry. 1965. Scoring and profitability models for evaluating andselecting engineering projects. J. Operations Res. Soc. Am. 13:550-569.
DiToro, D.M., J.D. Mahony, D.J. Hansen, K.J. Scott, M.B. Hicks, S.M. Mayr, and M.S.Redmond. 1990. Toxicity of cadmium in sediments: The role of acid volatilesulfide. Environ. Toxicol. Chem. 9:1487-1502.
EA Engineering, Science, and Technology. Undated. Terrestrial soil fauna in environmentalassessment and environmental management. Prepared for Exposure AssessmentGroup, U.S. EPA.
Eisner, R. 1987. Mercury hazards to fish, wildlife, and invertebrates. U.S. Fish Wildl.Serv. Rep. 85(1.10).
9-1
Federal Interagency Committee for Wetland Delineation (FICWD). 1989. Federal Manualfor Identifying and Delineating Jurisdictional Wetlands. U.S. Army corps ofEngineers, U.S. Environmental Protection Agency, U.S. Fish and Wildlife Service,and U.S.D.A. Soil Conservation Service, Washington, D.C. Cooperative technicalpublication. 76 pp. plus appendicies.
Lewis, S.C., J.R. Lynch, and A.I. Nikiforov. 1990. A new approach to derivingcommunity exposure g/>Hnes from "No-Observed-Adverse-Effects-Levels11. Reg.Toxicol. Pharmacol. 11:2 '30.
National Geographic Society. 1983. Field Guide to the Birds of North America. NationalGeographic Society, Washington, D.C. 464 pp.
Ohio Environmental Protection Agency (OEPA). 1989. Biological Criteria for theProtection of Aquatic Life: Volume III. Division of Water Quality Planning andAssessment, OEPA, Columbus, Ohio I
Ohio Environmental Protection Agency (OEPA). 1991. How clean is clean policy. July1991.
Shacklette, H.T. and J.G. Boerngen. 1985. Element Concentrations in Soils and OtherSurficial Materials of the Conterminous United States. U.S. Geological SurveyProfessional Paper 1270.
United States Environmental Protection Agency (U.S. EPA). 1988. Interim Guidance onAdministrative Records for Selection of CERCLA Response Actions. Draft.OSWER Directive No. 9833.3A. June 1988.
United States Environmental Protection Agency (U.S. EPA). 1988b. Superfund ExposureAssessment Manual. EPA/540/1-88/001. April 1988. i
United States Environmental Protection Agency (U.S. EPA). 1989a. Risk AssessmentGuidance for Superfund—Environmental Evaluation Manual. EPA/540/189/001.March 1989.
United States Environmental Protection Agency (U.S. EPA). 1989b. Ecological Assessmentof Hazardous Waste Sites: A Field and Laboratory Reference. EPA/600/3-89/013.March 1989.
United States Environmental Protection Agency (U.S. EPA). 1991a. Assessment andControl of Bioconcentratable Contaminants in Surface Water. March 1991 Draft.
United States Environmental Protection Agency (U.S. EPA). 1991b. Draft AnalyticalMethod for Determination of Acid Volatile Sulfide in Sediment. August 1991.
9-2
United States Environmental Protection Agency (U.S. EPA). 1991c. Assessment andControl of Bioconcentratable Contaminants in Surface Waters. Office of Water,March 1991 draft.
United States Environmental Protection Agency (U.S. EPA). 1992a. Report on theEcological Risk Assessment Guidelines Strategic Planning Workshop. EPA/630/R-92/002. February 1992.
United States Environmental Protection Agency (U.S. EPA). 1992b. Peer ReviewWorkshop on a Framework for Ecological Risk Assessment. EPA/625/3-91/022.February 1992.
United States Environmental Protection Agency Region 5. 1992c. Regional Guidance forConducting Ecological Assessments.
United States Fish and Wildlife Service. 1976. Habitat Evaluation Procedures. Division ofEcological Services. Washington D.C. 30 pp.
Woodward-Clyde Consultants (WCC). 1989. Appendix B, Revision 0, Site Safety Plan,Fields Brook Source Control RI/FS-SSP, Fields Brook Sediment Operable Unit EDI-SSP, Fields Brook Site, Ashtabula, Ohio. Prepared for Fields Brook SettlingCompanies, Ashtabula Ohio. Prepared by Woodward-Clyde Consultants, Chicago,Illinois. 5 May 1989. Project 86C3609D-150 and 86C3609E-220.
Woodward-Clyde Consultants (WCC). 1990a. Appendix D, Revision 3, Quality AssurancePlan for Sediment Quantification Design Investigation (SQDI), Fields Brook Site,Astabula. Prepared for Fields Brook Settling Companies, Ashtabula Ohio. Preparedby Woodward-Clyde Consultants, Chicago, Illinois. 29 June 1990. Project86C3609E-115.
Woodward-Clyde Consultants (WCC). 1990b. Sediment Operable Unit, TechnicalMemorandum No. 2, Wetlands Survey, Fields Brook Site, Ashtabula. Prepared forFields Brook Settling Companies, Ashtabula Ohio. Prepared by Woodward-ClydeConsultants, Chicago, Illinois. 2 November 1990. Project 86C3609E-244.
Woodward-Clyde Consultants (WCC). 1990c. Conceptual Design Memorandum - SedimentOperable Unit, Fields Brook Site, Ashtabula, Ohio. Prepared by Woodward-ClydeConsultants, Chicago, Illinois. 30 November 1990. Project 86C3609E-263, RevisionCR-0.
9-3
Woodward-Clyde Consultants (WCC). 1991. Phase I Analytical Data, Revision 0, SedimentOperable Unit, Sediment Quantification Design Investigation, Fields Brook, Ohio.Prepared for Fields Brook Settling Companies, Ashtabula Ohio. Prepared byWoodward-Clyde Consultants, Chicago, Illinois. 29 June 1990. Project 86C3609E-261.
Woodward-Clyde Consultants (WCC). 1992. SQDI Status Report, Sediment Operable Unit,Sediment Quantification Design Investigation, Fields Brook, Ohio. Prepared forFields Brook Settling Companies, Ashtabula Ohio. Prepared by Woodward-ClydeConsultants, Chicago, Illinois. 27 June 1992. Project 86C3609E-261.
9-4
ATTACHMENT A
DISCUSSION OF FIELDS BROOKPRP ORGANIZATION APPROACH TO
WETLANDS AND FLOODPLAINS
As discussed at our meeting on 13 July, a draft consolidated map illustrating approximatefloodplain and wetland boundaries in the Fields Brook watershed was prepared and submittedto USEPA. This map reflects current understanding of the watershed structure including thelocations of the stream channel, 10- and 100-year floodplains, and wetlands. In addition, themap shows residential and potential source locations in which floodplain sediments areproposed for treatment in the same manner as the stream channel sediments discussed in the1986 Record of Decision.
In the following paragraphs we briefly discuss the procedures employed in deriving thewatershed classification and the significance of the results for the Sediment Operable Unitand wetlands assessment. The conclusion of our analysis of available information is that, ingeneral, sediments in areas delineated as "floodplain" and those delineated as "wetland" areindistinguishable in structure and function, that potential for transport does not differ amongthese sediment categories, and that biotic and human exposure potential is identical.Exceptions to this conclusion are: residential areas which present an unacceptable humanhealth risk; highly contaminated areas with a high potential for unacceptable ecological risk;and the limited areas of streamside erosion. Based on this analysis, we suggest that a dualapproach be applied to assessment and management of the watershed. Residential areas,potential source areas, and erosional areas will be fully delineated and treated in the samemanner as stream channel sediments. All other areas mapped will be evaluated under thewetlands risk assessment and treated separately for risk characterization and evaluation ofremedial alternatives.
Objectives and Procedures
The primary objective of the wetlands delineation was to document the wetland/uplandboundary adjacent to the Fields Brook channel to support subsequent investigations andmanagement activities. In most of the watershed (downstream of approximate state planecoordinates E 2473500, N 816000) wetlands boundaries were delineated by applying criteriaestablished in the Federal Manual for Identifying and Delineating Jurisdictional Wetlands("Wetlands Manual", Federal Interagency Committee for Wetlands Delineation 1989). In theflooded areas north of this location, wetlands were characterized by the extent of hydric soiland visual observation.
The Wetlands Manual provides a three-component approach to wetlands classification,incorporating data on the relative predominance of hydrophytic vegetation, the presence ofhydric soils, and indications of wetland hydrology. The wetlands delineated on the enclosedmap were characterized by sampling across the wetlands/upland boundary at 12 transectsacross the watershed and marking and mapping the location along the transect at which onlytwo of three necessary wetlands criteria were met. Transect locations were surveyed andboundary locations were mapped from survey points. Additional details of the wetlandsdelineation can be found in Technical Memorandum No. 2 submitted on 5 November 90.
Primary objectives of the floodplain delineation were to aid in defining the extent ofcontamination, to support selection of sampling locations in subsequent phases ofinvestigation, and to assist in the design of remediation facilities. Floodplain areas for 10-and 100-year frequency events were estimated by hydrologic and hydraulic modeling usingU.S. Army Corps of Engineers Flood Hydrograph (HEC-1) and Water Surface Profiles(HEC-2) packages. Model output flood elevation estimates validated well to an observedevent of approximately 35-year frequency (Table 1).
The stream channel proper was delineated in detail by on-site ground truth. Channelboundaries were staked and mapped, and representative sites were surveyed in.
Findings
Throughout the Fields Brook watershed, the estimated 10- and 100-year floodplains generallyoccur within the wetlands that are contiguous with the brook. This is to be expected basedon the location and configuration of the watershed. Because of the relatively flat topographyand northern location, watershed hydrodynamics and biotic community structure determinantsare low-intensity processes which occur over relatively large areas and relatively long timespans. The local system is generally controlled by such processes as snow melt and hydricsoil maintenance rather than by sudden rainfall events.
These controlling parameters have important consequences for the investigation andremediation of the watershed. In general, sediments in the wetlands beyond the streamchannel proper are in depositional, rather than erosional, environments. This was confirmedduring a site reconnaissance conducted by PRP and Agency personnel. Heavily vegetatedwetlands ecosystems extend from uplands directly to the banks of Fields Brook. In someplaces, the wetlands have been altered by human (a stretch of maintained meadow) or natural(areas of beaver use) activities, but these areas are also heavily vegetated and the watershedbeyond the stream channel is generally a clearly depositional environment. Several smallareas of localized in-stream bank erosion were noted, but these were associated withlocalized depositional zones (for example, one area had undercut banks on the outside, anddepositing bars on the inside, of a stream curve), indicating little net downstream transport.Extensive areas of flooded soils were observed, indicating overbank flow with subsequentloss of velocity and deposition of water column suspended solids. No areas beyond thestreambed were noted to have extensive exposed glacial till (sands, gravels, cobbles orboulders) or bedrock. The unconsolidated materials forming the floodplain and wetlandsediments are characteristic of depositional systems. Thus, the net flux of sediment isgenerally from the stream into the wetland ecosystem.
Additional findings of the site reconnaissance included:
1. no clear biological delineation of "floodplain" vs. "wetland" areas of the watershed.This is expected (for reasons detailed above), and indicates that the wetland ecosystemfrom the upland boundary to the stream channel proper functions as a singleecological unit
2. consistently low levels <;* human use throughout the watershed, mainly consisting ofrecreational fishing and i; 5 in upper reaches (upstream of E 2473000). Thissuggests that potential human exposure to any contaminants present in the wetlands isnot clearly differentiable by "floodplain" vs. "wetland" areas
3. no clear physical (geologic, hydrologic, or sedimentologic) delineation of "floodplain"vs. "wetland" areas of the watershed. Throughout the watershed, the gentle slope andfine sediments of the wetland area are maintained, indicating that the "floodplain" and"wetland" function as an integral sink (not source) for potential contaminant transport.
Conclusions
Considered as a whole, the findings of the studies available to date strongly indicate that theareas mapped as "floodplain" and "wetland" are not functionally differentiable. Forinvestigation and possible remediation, these areas should be treated as a single integral unit.The stream channel proper is a higher-energy, clearly delineated area best addressed as adistinct entity. The ecology, geology, and hydrology of the floodplain and wetland areas,while quite different from the stream channel, are internally similar, and thus exposure,source, and sink processes will be similar. Potential exposure and associated potential risksremain to be quantified in this area. It is clear from preliminary analyses (of existinginformation and site reconnaissance) that different concerns pertain to the wetland/floodplainthan pertain to the stream channel, but that concerns are not differentiable across thewetland/floodplain. An appropriate approach to investigation would account for potentialdeposition of contaminants due to flooding (by appropriate location of samples), but wouldcharacterize the nature and extent of contamination and potential associated risks throughoutthe floodplain/wetlands area. Thus, we suggest a dual approach to the investigation andmanagement of the floodplain/wetland areas. Certain areas will be treated in the samemanner as the stream channel sediments discussed in the 1986 Record of Decision, using thesame action levels and cleanup criteria. These areas fall into three categories: erodingsediments which, if not controlled, are potential sources of recontamination for the brook;highly contaminated areas which present potentially unacceptable sources of ecological risk;and residential areas which present potentially unacceptable human health risk. Erosionalareas were found during field reconnaissance to be very small and localized, and cannot bemapped effectively on a watershed scale. All three of these categories will be delineated andtreated in a fashion similar to stream channel sediments. All other areas will be treatedseparately for risk characterization and evaluation of remedial alternatives.
Table 1. Comparison of estimated and observed flood elevations.
Cross SectionID1-XS2
1-XS102-1XS22-2XS13-XS13-XS54-XS3
5-1XS36-XS2
7-2XS18-1XS18-1XS98-2XS1
8-2XS38-3XS2
Estimated10-Year Elev(ft)578.4581.2582.5590.7593.6600.3607.9613.2617.8624.6625.5630.6631.6635.7639.2
Observed35-Year* Elev\
579.0580.0581.0591.0599.0601.0608.2612.5618.7625.0625.5630.6631.0Not EstimatedNot Estimated
Estimated100-Year Elev(ft)580.6583.4584.9592.4595.2601.5609.2614.3618.6625.5626.2631.6632.8636.5640.2
* Based on observed flood elevations at select locations.