FINAL

STREAMLINED REMEDIAL INVESTIGATION/FEASIBILITY STUDY

REPORT

Velsicol Chemical Site St. Louis, MI

August, 1998

Prepared by: U.S. EPA Region 5

VELSICOL CHEMICAL SITE PINE RIVERIST. LOUIS IMPOUNDMENT

FOCUSED REMEDIAL INVESTIGATIONlFEASIBILITY STUDY

SECTION 1 - INTRODUCTION 1.1 Purpose

SECTION 2 - SITE CHARACTERIZATION 2.1 Site Description and Background

2.1.1 Site History 2.1.2 Regional Demographics 2.1.3 Regional Geology 2.1.4 Hydrology and Hydraulics 2.1.5 Possible Exposure Pathways

2.2 Source, Nature, and Extent of Contamination 2.2.1 Sediment Analytical Data

2.2.1.1 1980 NEIC Survey 2.2.1.2 1981 NEIC Survey 2.2.1.3 1996 US EPA Survey 2.2.1.4 1997 US EPA Survey 2.2.1.5 Summary and Conclusions

2.2.2 Fish Data 2.2.3 Surface Water Data Summary

2.3 Streamlined Risk Assessment 2.3.1 Scope and Purpose 2.3.2 Background 2.3.3 Data 2.3.4 Exposure Pathways 2.3.5 Toxicity 2.3.6 Risk Characterization 2.3.7 Uncertainty 2.3.8 Conclusion 2.3.9 References 2.3.10 Addendum to 1996 Baseline Risk Assessment

2.3.10.1 Scope and Purpose 2.3.10.2 Exposure Considerations 2.3.10.3 New Data 2.3.10.4 Toxicity 2.3.10.5 Risk Characterization

2.3.10.5.1 Fish Consumption Risks - 1997 Data 2.3.10.5.2 Current Dermal Risks

2.4 Ecological Risk Assessment 2.4.1 Introduction 2.4.2 Problem Formulation

2.4.2.1 Conceptual Model 2.4.2.2 Assessment Endpoints 2.4.2.3 Measurement Endpoints

2.4.3 Characterization of Ecological Effects 2.4.3.1 Fish-eating Birds 2.4.3.2 Benthos

2.4.4 Characterization of Exposure 2.4.4.1 Fish-eating Birds 2.4.4.2 Benthos

2.4.5 Risk Characterization 2.4.5.1 Fish-eating Birds 2.4.52 Benthos

2.4.6 Uncertainty 2.4.6.1 Overestimate Risk 2.4.6.2 Underestimate Risk 2.4.6.3 Unknown Effect on Risk Estimate

2.4.7 Conclusions 2.4.8 Literature Cited

2.5 Cleanup Goals For DDT in the Pine River

SECTION 3- 3.1 3.2 3.3 3.4 3.5 3.6 3.7

IDENTIFICATION AND SCREENING OF REMEDIAL TECHNOLOGIES 82 Remedial Action Objectives 82 ARAR Identification 83 General Response Actions 85 Identify and Screen Remedial Technologies and Process Options 85 Evaluate Process Options 89

J Assemble Alternative 91 Alternatives Screening Process 94

SECTION 4- DETAILED ANALYSIS OF ALTERNATIVES 4.1 Introduction 4.2 Alternatives for Detailed Analysis 4.3 Nine Criteria Analysis of Individual Alternatives 4.4 Comparative Analysis of Alternatives 4.5 Recommended Alternatives (Alternatives 4,5 and 6)

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TABLES Page

TABLE 2.2-1 Maximum Total DDT Conc and Surface Area (199611997 Data)

TABLE 2.2-2 Total DDT Concentration per Depth Interval (1 99611997 Data)

TABLE 2.2-3 Concentration, Area, Volume and Mass TABLE 2.2-4 Total DDT Concentrations per Depth Interval (1980 Data) TABLE 2.2-5 Total DDT Concentrations per Depth Interval (I981 Data) TABLE 2.2-6 Total DDT Concentrations per Depth Interval (1996 Data) TABLE 2.2-7 Total DDT Concentrations in Sediment below

St. Louis Dam TABLE 2.2-8 Toal DDT Concentration per Depth Interval (1997 Data) TABLE 2.2-9 Skin-off Filet Carp Samples TABLE 2.2-10 Carp Data Specifics

L TABLE 2.3-1 Fish Data

TABLE 2.3-2 Sediment Data (1996 Data) TABLE 2.3-3 Summary of Fish Consumption Risks TABLE 2.3-4 Summary of Dermal Exposure Risks TABLE 2.3-5 Exposure Assumptions TABLE 2.3-6 Current Risks From Fish Consumption

I TABLE 2.3-7 Dermal Cancer Risks (1997 Data) TABLE 2.4-1 Sediment Screening Values TABLE 2.4-2 Severe Effect Levels (SEL) for Sediments TABLE 2.4-3 Benthic Community Threshold and Median Lethal

Concentration for DDTr. TABLE 2.4-4 Contaminant Levels in Whole Carp, St. Louis

Impoundment, 10117197, and Dose Estimates to Heron TABLE 2.4-5 Range of Surficial Sediment Sample Results, St. Louis

b Impoundment, July 1997 TABLE 2.4-6 Mean Surficial Sediment Sample Results for DDTr TABLE 2.4-7 Risk Characterization, Great Blue Heron,

St. Louis Impoundment TABLE 2.4-7 Comparison of Sediment Screening and Benchmark

Values with Surficial Sediment Analytical Results, St. Louis Impoundment, Velsicol Site, Michigan

TABLE 2.5-1 Volume Break Point Analysis TABLE 2.5-2 Post Remedial Risk TABLE 3.2 Chemical, Action, Location Specific ARAS following page TABLE 3.4 Preliminary Screening of Potential Remedial Technologies TABLE 3.5 Effectiveness, Implementability, Cost TABLE 3.7 Screening Evaluation of Alternatives

APPENDICES

Figures

Appendix A - SedimentIFish Analytical Data

Appendix B - Detailed Cost Estimates

SECTION 1 - INTRODUCTION

This document presents a streamlined Remedial Investigation (RI) and Feasibility Study

(FS) for sediment contamination in the Pine RiverISt. Louis Impoundment at the Velsicol

Chemical Superfund Site which is listed on the National Priorities List (NPL) under the

Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA),

as amended. U.S. EPA Region 5 completed this document in consultation with the Michigan

Department of Environmental Quality (MDEQ). The purpose of the RI is to determine the nature - and extent of contamination in the St. Louis Impoundment. Remedial alternatives will be

developed and evaluated in the streamlined FS. The design q d implementation of a selected

remedy will follow in the Remedial DesignIRemedial Action (RDIRA) phase.

The purpose of the RIIFS process is to characterize the nature and extent of risks posed by L

uncontrolled hazardous waste sites and for evaluating potential remedial options. The objective

of the RIIFS process is not to remove all uncertainty, but rather to gather information sufficient to

support an informed risk management decision regarding which remedy appears to be most

appropriate for a given site

The objectives of this RI are to:

* Characterize the nature and extent of sediment contamination in the Pine River and St.

Louis Impoundment;

t Characterize the human health risk from ingestion of fish from the Pine

River:

t Characterize the ecological risks at the site;

t Assess the actual and potential exposure routes; and

* Gather data and information to the extent necessary and sufficient to

support the development and evaluation of remedial alternatives in the FS.

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SECTION 2 - S I T E C T F , R I Z m

The Velsicol Chemical Corporation Main Plant Site ("Site") is an approximately 50 acre

parcel that was once occupied by a chemical processing plant located on the Pine River adjacent

to the St. Louis Impoundment (SLI). See Figure 2-1. The chemical plant operated from 1936 ,d

through 1978 and manufactured a variety of organic and inorganic chemicals including

polybrominated biphenyls (PBB), hexabromobenzene (HBB), 1 ,I, 1-Trichloro-2,2-bis(p-

chlorophenyl) Ethane (DDT), and Tris(2,3-Dibromopropyl) Phosphate (TRIS). The Site

I represents a threat to public health, welfare, and the environment because of widespread

contamination caused by direct discharges to the Pine River. The Site was proposed for

inclusion on the National Priorities List (NPL) on December 30, 1982, and appeared on the final

NPL on September 8, 1983. The NPL is the list of the worst hazardous waste sites in the United L

States.

The Site, which consists of the main plant site and the Pine River, have been the subject

of a number of investigations conducted by the MDEQ (formerly the Michigan Department of

Natural Resources (MDNR)), U.S. EPA and Velsicol. The studies revealed main plant site soils

contaminated with PBB, HBB, TRIS and other contaminants; ground water contaminated with

vinyl chloride, toluene, chlorobenzene, DDT and other contaminants; Pine River sediments

contaminated with PBB, HBB and DDT; and elevated levels of PBB, DDT and other

contaminants in fish from the Pine River. Pine River surface water did not contain measurable

levels of contaminants associated with the Site. Also included in some of these studies were

other site characterization data (hydrogeology, hazard assessment, etc.) upon which remedial

action alternatives could be evaluated.

Initial remedial measures for the Site began in October, 1978 with closure of the Plant,

cessation of discharges to the Pine River, and demolition of buildings and structures on the main

plant site. Site characterization investigations began in 1978 and continued through 1980.

Upon completion of the site characterization the State of Michigan, U.S. EPA, and

Velsicol negotiated an agreement that included a remedy directed at stopping the migration of

PBB, HBB, DDT and other contaminants found at the main plant site into the environment.

Remedial actions for the Pine River were not included as part of this agreement. The remedy

selected included excavation and disposal of contaminated soils in an on-site disposal area;

isolation of the main plant site from surrounding groundwater with a 2 foot thick, low-

permeability sluny wall; covering the main plant site with a 3 foot thick, low-permeability, clay

cap; implementation of other measures including dust control, construction equipment

decontamination, air monitoring, monitor well installation, ground water elevation monitoring,

control of ground water levels within the main plant site boundaries, and provisions for long-

term operation and maintenance of the main plant site. This remedy was implemented by

Velsicol as a requirement of a December 27, 1982 judicial Consent Judgment ("1982 CJ")

between U.S. EPA, the State of Michigan, and Velsicol.

Implementation of the remedy required by the Consent Judgment began in January, 1983,

and was completed, on schedule, in November, 1984. The main plant site is now covered with

) shallow-rooted grass, and. to restrict access, enclosed by a chain link fence. Velsicol is currently

operating and maintaining the main plant site in accordance with an approved operation and

maintenance plan requiring weekly inspections for signs of deterioration, quarterly monitoring of

gas vents, measurement of groundwater levels within the contained main plant site, and slurry

wall permeability testing.

The Consent Judgment did not require Velsicol to remove the contaminated sediments

from the Pine RiverISt. Louis ~m~oundment . Contamination of fish in the river was addressed

by health advisories issued by the State of Michigan. A no consumption advisory for all species L

of fish was initially published in the Michigan fishing guides in 1977.

Water levels inside the Containment System (slurry wall and cap) remained below the

level set by the 1982 CJ until February 1992. The exceedence in February was temporary, water

levels dropped below the CJ level in June 1992. The water levels again exceeded the CJ level in

February 1993 and did not drop below the required level until Velsicol completed a ground water

removal action, pumping 1.25 million gallons of water from the Containment System with off-

site disposal. In late 1994 Velsicol removed another 1.28 million gallons of ground water from L

the system to maintain the 1982 CJ level. Velsicol continued to pump water from the

Containment System approximately every 6 months to maintain the required water level. In

1996, Velsicol completed a comprehensive assessment of the Containment System. Velsicol

completed the assessment with U.S. EPA and MDEQ ("the Agencies") oversight. Assessment of

the clay cap included collection of samples from the upper portion of the cap on a 250 foot grid

and analyzed for permeability, grain size, and Atterberg limits. Assessment of the containment

wall consisted of installation of inclinometers inside and outside the slurry wall at seven

locations, installation of settlement plates at seven locations inside the slurry wall, collection of

samples at nine locations for permeability analysis; installation of upper zone piezometers on the

inside and outside of the wall at five locations; water level measurements and free product

screening from all monitoring wells and piezometers; and dye tracer study at the five locations

were the piezometers were installed. Velsicol published a report entitled Final Containment

System Assessment Report, Former Michigan Chemical Plant Site, St. Louis, Michigan, October

1, 1997 detailing the Containment System assessment and results.

The Agencies believe the results of the Containment System Assessment document that

the clay cap is leaking, probably due to the fact that there is no frost protection layer on top of the

cap. Velsicol concluded in their report of the findings that the Containment System is working as

designed. On December 11, 1997 Velsicol submitted a work plan entitled Work Plan Post-

Closure Cap Maintenance, Former Michigan Chemical Plant Site, St. Louis, Michigan in which

Velsicol states it willconduct maintenance of the clay cap during summer, 1998 by recompacting

areas of the clay cap.

Simultaneously with the Containment System Assessment, the Agencies began a

reassessment of contamination in the Pine RiverISt. Louis Impoundment. During summer, 1996

sediment cores were collected from 23 locations in the St. Louis Impoundment and analyzed for

PBB, HBB and DDT. Surficial sediment samples were also collected from depositional areas in

the lower Pine River (below the St. Louis dam). During summer, 1997 the Agencies collected

another round of sediment cores from 28 locations and analyzed them for DDT and total organic

carbon (TOC). MDEQ collected fish for analysis. The results of these sampling events are

detailed in Section 2.2 of this RIIFS.

Gratiot county encompasses the geographical center of Michigan's Lower Peninsula

between the industrial areas of the south and the recreational areas of the north. The cities of

Alma and St. Louis are located in the mid-northern region of the county. With 839 persons

employed by means of agriculture, forestry, and fisheries, Gratiot County boasts a broad variety

of businesses and industries built on a strong agricultural base. Broad expanses of level terrain 'V

produce crops of sugar beets, corn, wheat, corn oats and other grains and beans; gently rolling

pastures support beef and dairy cattle. Agriculture accounts for more than 76% of the county's

total land use. Petroleum products from the Alma refinery fuel transportation and lubricate the

I machinery of industry and agriculture. (U.S. Census Bureau, Economic Projle, Gratiot County

taken from web site on 12/08/97).

There are a total of fifty-five principal employers in the county, seven of which employ

between 230 and 790 towns persons each. These key employers range from the local University, b

Alma College, and Gratiot Community Hospital to mold shops, an automotive component

manufacturer, a petroleum refinery, and other such industries. With a total county population of

39,785, the Gratiot unemployment rate now stands at 6.6% (U.S. Census Bureau, Economic

Profile, Gratiot County taken from web site on 12/08/97). This rate, which has lowered

significantly from the 1980 high of 13.4%, is still high when compared to the national

unemployment rate of 4.9% for August 1997 (US Dept of Labor, OPA Press Release, 09/05/97).

The percent of high school graduates in the county is 77.1% and the percent of college graduates

in the area is 10.9%. The median family income in 1990 was $14.095/year (U.S. Census Bureau,

Economic Profile, Grariot County taken from web site on 12/08/97).

In 1996 the State of Michigan established the nation's first incentive program to establish

tax free areas called Renaissance Zones. The purpose of creating a Renaissance Zone is to

generate economic growth in economically distressed areas of the state. Renaissance Zones have

been designated in eleven communities in the state, one being Gratiot County (U.S. Census

Bureau, Economic Projle, Gratiot County taken from web site on 12/08/97).

1990 demographic data for Gratiot county show that this area is predominately composed

of white persons (97%). The median age is 3 1 for the region. (Bureau of the Census).

In 1990, Alma and St. Louis were home to 9,039 and 3,828 residents respectively. The

demographic data for these areas are nearly identical to those of the whole county given above

(Bureau of the Census).

The area occupied by Alma and St. Louis, Michigan represents a boundary between

glacial morainal deposits and glacial lacustrine deposits. The Velsicol Site overlies glacial

morainal deposits and has a stratigraphy that varies from pure clay to sand and gravel typical of

glacial till in this region. A description of a typical surficial stratigraphy for this area is detailed

below.

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Typical glacial stratigraphy (top 150 ft.) In St. Louis Area

- Sand and Gravel 0 - 10 feet

Pure Clay - Blue Glacial Clay 10 - 60 feet

Sandy Brown Clay - Weathered 60 - 80 feet

Mostly Sand with - SomeClay 80 - 150+ feet

(Letter from Murray C. Borrello to Kathy Rexing (December 16, 1997) (discussing Pine River

Morphology)

Soils in and around the Velsicol site range from sand to loamy sands. The primary soil

types are Marlette sandy loam, Spinks loamy sand, Selfridge loamy sand and Belleville loamy

sand. The Velsicol main plant site is almost entirely Spinks and Belleville loamy sand, with only

a small portion of the southern end of the property being Marlette sandy loam (Soil Sunrey of

Gratiot County, Michigan, U.S. Department of Agriculture, April, 1979).

The top unit of bedrock in this area is Pennsylvanian sandstone from the Grand River

Formation (Conemaugh Series). It is a pure sandstone with relatively high permeability.

Pumping rates in the sandstone in this area are approximately 60-75 gallmin. Depth to bedrock

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in the region ranges from approximately 175 - 360 ft. below grade. Depth to bedrock in the St.

Louis area ranges between 250 - 360 ft. below grade, and around the Velsicol site closer to 300 -

350 ft. below grade.

The Pine River is part of the Saginaw RivedSaginaw Bay drainage basin with a total

drainage area of 312 square meters. The Pine River flows northeast toward Midland for 20.5

miles where it discharges into the Chippewa River and then into the Tittabawassee River. The

Tittabawassee then flows southeast toward Saginaw where it discharges into the Saginaw River.

The Saginaw River then flows north where it empties into Saginaw Bay in Lake Huron

(Figure 2-2).

The Pine River is impounded in both Alma and St. Louis. The Alma dam is located

approximately 4-5 miles upstream from the Site. The St. Louis Impoundment is adjacent to the

Site and immediately downstream of the Site is the St. Louis dam.

The portion of the Pine River and St. Louis Impoundment subject to consideration in this W

document includes the Pine River from approximately the M-46 bridge to the Mill street bridge.

The total area of this stretch is approximately 25 acres. The SLI is identified in Figure 2-1,

which also identifies the areas described as the Main Plant Site, the Pine River, the M-46 bridge,

the Mill Street bridge and the St. Louis dam.

The Pine River and SLI are a navigable waterway in the area of St. Louis. Current uses of

the Pine River and St. Louis Impoundment are impaired due to the sediment contamination. Due

) to the fish consumption advisory, recreational anglers are limited to catch and release fishing

only. Swimming and boating are considered undesirable due to the contamination. Generation

of electricity is currently the only acceptable use of the river and impoundment. The

impoundment provides hydraulic head for power generation. The City of St. Louis estimates that

from July 1996 to June 1997 the St. Louis dam generated 1.35 million kilowatt-hours of

electricity, 4% of the total kilowatt-hours sold to the City of St. Louis during that same time

frame.

The closest gauging station to the site is located on the right bank of the Pine River, 270 C

feet downstream from the Superior Street Bridge in Alma. The location is 0.6 mile downstream

from the Alma dam and 5.2 miles upstream from the St. Louis dam. (USGS End of Year

ReDort.1993). I

Within the SLI, the water depth to sediment is generally between 7 and 10 feet. The

maximum observed depth during June 1993 sampling was 12 feet near the inlet to the

hydroelectric plant.

The City of St. Louis participates in the national Flood Insurance Program. A Flood

Insurance Study (FIS) was prepared for the Pine River in the City of St. Louis by the Federal

Emergency Management Agency (FEMA) in 1989. The FIS indicates that flooding in the City of

St. Louis is primarily caused by overflow of the Pine River, however, the potential for flood

damage is not great because of the steep banks and flood elevation regulation provided by the St.

Louis dam. The FIS presents the methodology and results of hydrologic and hydraulic analyses

performed for the Pine River to determine water-surface elevations corresponding to the 100-year

discharge both upstream and downstream of the dam. Upstream of the dam, where the

contaminated sediments are located the flood profile is based on a starting water surface

elevation at the dam that was derived from a series of 38 annual maximum pool elevations as

provided by the dam operator. The U.S. Federal Highway Administration's WSPRO model was

used to compute water surface elevations on the Pine River for the St. Louis FIS.

Fish ingestion is the main pathway of concern. Other possible pathways are dermal

uptake of sediment and incidental ingestion of sediment. The streamlined risk assessment, which

has been prepared by U.S. EPA Region 5 is presented in Section 2.4 of this RIFS report.

Sediment data was collected from the Pine RiveriSLI in 1980, '81, '96 and '97. A

detailed summary of the sampling surveys is presented in Section 2.2.1. Body burden of

contamination in fish has been monitored by MDEQ since 1983. Fish collection and analysis

were completed in 1983, '85, '94, '95 and '97. A detailed summary of the fish surveys is

presented in Section 2.2.2. Because rivers are highly dynamic systems, EPA has focused its

analysis on the sediment and fish data collected in 1997. However, sediment data from 1996

was used to evaluate the lower basin because an equipment failure precluded the collection of

sediment cores from that area in 1997.

The horizontal extent of total DDT in sediments of the Pine River and SLI was estimated

-1 based on the 1996 and 1997 data as explained above. The maximum concentration of total DDT

at each sample location was evaluated. Interpolation of the maximum concentration was

completed to delineate the surface area of total DDT concentrations exceeding 1, 10, 100, 500,

and 1,000 ppm (see Table 2.2-1).

DDT Conc cd&&xha (199611997 Data)

Total DDT concentrations were generally found to increase with depth (see

Table 2.2-2). with the majority of the contamination located in the 6-30 and 30-54 inch intervals.

The maximum concentration of 32,600 ppm was observed in one sample collected from a 6 to 42

Maximum Concentration (ppm)

1

10

100

500

1,000

L inch interval. The surficial sampling zone (0 to 6 inch interval) contained a maximum

concentration of total DDT of 229 ppm. The bottom sediment interval, 54 to average refusal

depth of 1 12 inches contained a maximum total DDT concentration of 822 ppm. The maximum

refusal depth, or maximum depth of sediments observed during the 1997 sampling event, was

144 inches (I2 feet).

Surface Area (Acres)

65

31.0

19.5

11.9

6.5

Table 2.2-2: Total DDT Concentration per Depth Interval (199611997 Data)

The surface areas and depths of contamination identified above were subsequently used to

estimate the volume of sediment associated with each concentration (i.e., 1, 10, 100,500 and

1,000 ppm). The areas and volumes for each concentration are presented on Figures 2-3 through

2-6 and in Table 2.2-3.

Avg. Conc. (ppm) Min. Conc. (pprn) 7 Depth Interval (in.)

0 - 6

6 - 30

30 - 54

54- 112

Table 2.2-3: Concentration, Area, Volume and Mass

k d

Max. Conc. (ppm)

* The maximum concentration was found in a sample collected from 6 to 42 inches.

229

32,600*

32,600'

822

Conc. (ppm)

1

10

100

500

1000

28.4

1485

1639

130

1.3

1.8

2.1

2.4

7

Mass (Ib)

540,000

533,000

529,000

519,500

490,700

Area (acres)

65

31

20

12

6

Volume (cy)

516,650

260,330

169,000

104,200

48,000

The method used to calculate volume is explained in Section 2.2.1 It should be noted that

these volume estimates do not include additional volumes which may need to be removed due to

sediment sloughing or lack of dredging precision, if an alternative incorporating dredging is

selected.

U.S. EPA used ArcView software to analyze the sediment data. The data was evaluated . ... with inverse distance weighting (IDW). IDW creates a grid of equal size cells. Each cell does

not contain a sediment data point so the software assigns a probable concentration to cells

without a data point according to a weighted formula of nearest neighbor sample points (i.e., the

I closer a sample point, the more its concentration influences the value of the grid cell). Because

of the low number of sample points in the SLI, the four nearest neighbors were used for analysis.

To calculate a surface-area weighted concentration, the concentration of each grid was summed

and divided by the total area. Volumes were calculated by using the IDW method to interpolate V

the data for sediment depths. The sediment depth grids were used to better illustrate the range of

the sediment thickness. Each grid cell was given a depth value from the interpolation. Using the

IDW method where each grid is created of equal size, the area of each grid was determined based

on a grid cell size of one square meter. The area for each grid was multiplied by the depth of

each grid cell; therefore giving a volume for each grid cell. The volume for each grid cell was

then summed together to give a total volume.

IDW creates concentration grids through interpolation of the concentration data and

allows for a more visual picture of the concentration range. The interpolations are also able to

simulate a more realistic distribution of concentration.

The analytical data associated with sediment, fish and surface water sampling surveys that

were conducted in the Pine River and St. Louis Impoundment are summarized below. Appendix

A contains data from all sampling surveys.

VI In June of 1980, by the request of the U.S. EPA, the National Enforcement Investigations

Center (NEIC) conducted a limited sampling survey of the Pine River. The survey goals were to

identify the contamination contributed to the Pine River by the Velsicol Chemical Corporation

and to ascertain additional information needed to assess remedial action for the contaminated

Pine River (Forba, 1980).

The survey was conducted in June, 1980. The area of concern included the Pine River

between the Cheeseman Road bridge and the St. Louis Municipal wastewater treatment plant

outfall. A total of thirteen sediment samples and fourteen water samples were collected (see

Figure 2-7). All samples were analyzed for 1,1,1 -trichloro-2;2-bis(chlorophenyl) ethane (DDT

and analogs p,p7-DDT, o,p'-DDT, p,p'-DDE and p,p'-DDD), polybrominated biphenyl (PBB),

hexabromobenze (HBB) and tris(2, 3-dibromopropyl) phosphate (Tris).

Analytical results showed that all of the sediment cores were contaminated to some

degree by DDT and its analogs. A maximum total DDT concentration of 44,000 ppm was found

in sample RSS-6A at depth interval 13.5 - 23 inches. Concentrations of DDT over 2,000 ppm

~... ) were found in four of the samples; RSS-6A, 6B, 7 and 9A. The most highly contaminated

sediment samples were collected from the middle basin of the St. Louis Reservoir adjacent to the

Velsicol plant site. Sediment cores collected upstream of the M-46 bridge were relatively

uncontaminated by DDT (Forba, 1980). Table 2.2-4 summarizes the data from the 1980 survey

by depth interval.

Table 2.2-4: Total DDT Concentrations per Depth Interval (1980 Data)

Results from the analyses on HBB and PBB revealed that three samples, RSS-6A, 7, and

Depth Interval (in)

0 - 13.5

13.5 - 23

8, had PBB concentration levels greater than 70 ppm. HBB was also detected at levels greater

than 20 pprn in samples RSS-6A, 7,8, and 9A. The maximum concentration for HBB and PBB

was found in RSS-6A at 540 ppm and 270 pprn respectively.

Elutriation testing under laboratory conditions showed that DDT was bound tightly with

the sediment and did not desorb or solubilize readily. Surface water sample analyses also

showed levels of these contaminants to be below the detectable limit. However, fish tissue

analyses performed by the MDEQ showed high levels which exceeded a Federal Department of

Agriculture (FDA) standard of 5 pprn for DDT, resulting in a ban against consumption of the

Pine River fish (Forba, 1980).

Max. Conc. (pprn)

4,7 10

43,700

Avg. Conc. (pprn)

1,043

21,850

Min. Conc. (pprn)

0.05

0.02

In November 1981 U.S. EPA conducted additional sampling to supplement the June,

1980 sampling survey. The survey was needed to help define the areal and vertical distribution

of the DDT contamination.

Sediment cores were collected and water and sediment depths were measured at 23

locations. Sediment depths ranged from 1.5 to 9 feet. The deepest sediment depths (8-9 feet)

were found in the extreme upper end (Stations 04,05, and 06) and the lower end of the middle

basin (Stations 12, 13, 16, and 17). Figure 2-8 illustrates the Station locations.

Analysis was completed for all DDT analogs (o,p'DDE; p,p'DDE; o,p'DDD; p,p'DDD;

o,p'DDT; and p,p'DDT). Less than 5% of the DDT was found in the top 4 inches of the

sediment, leaving over 95% DDT contamination in the depth intervals between 4 and 40 inches

(Forba, 1982). This may indicate that resuspension is occurring or that subsurface sediments are

bioavailable to fish.

The highest concentrations of total DDT were found in the middle basin of the SLI which

extends from the main plant site jetty to the Mill Street bridge (see Figure 2-8). The average

concentration of total DDT found in the samples taken in the middle basin was 3,500 ppm. This

was the part of the basin where the wastewater from the former plant organic production was

discharged. The highest total DDT levels were found at Stations 07 and 08 with levels at 26,000

ppm and 8,800 ppm respectively. These two stations were nearest to the wastewater discharge

and the location of the 1980 high of 44,000 ppm.

The sediment cores were divided into five depth intervals: 0 to 4,4 to 16, 16 to 28, 28 to

) 40 and 40 inches and below. The maximum total DDT concentration of 26.000 ppm was found

in the subsurface sediment interval of 16 to 28 inches. This maximum was located on the

southwest side of the impoundment adjacent to the plant at Station 07. The average total DDT

concentration at this interval was 2,108 ppm. An average of 1,011 ppm was found in the 28 to

40 inch segment of the sediment cores. Lower total DDT concentrations were found in the

surface interval, 0 to 4 inches, with the maximum of 4,000 ppm found on the north side of the

impoundment near the park at Station 14. Average total DDT concentration levels were

approximately 188 ppm for the surface interval. Maximum, average and minimum ?Ld

concentrations are summarized in Table 2.2-5.

Table 2.2-5: Total DDT Concentrations per Depth Interval (I981 Data) 'i

The core samples showed detection of PBB and HBB. High levels were found adjacent

to the Velsicol plant site on the southwest side of the Impoundment. Maximum concentrations

for PBB and HBB were found to be 330 ppm (0-4 inch interval) and 9,298 ppm (4-16 inch

interval), respectively.

Depth Interval (in)

0 - 4

4 - 1 6

16 - 28

28 - 40

Max Conc. (ppm)

4,012

2,825

25,690

4,772

Avg. Conc. (ppm)

188

24 1

2,108

1,011

Min. Conc. (ppm)

0.5

0.4

0.12

0.12

In May 1996, the U.S. EPA and MDEQ conducted another sediment sampling survey.

The survey was conducted with the use of the EPA's research boat, the Muddpuppy. Sediment

cores were collected from twenty locations (see Figure 2-9). Sediment samples were collected

May 21-23, 1996 and analyzed to better assess current conditions in the St. Louis Impoundment

and Pine River. The data was summarized in a report entitled Status of the St. Louis

impoundment in the Vicinity of the Former Velsicol Chemical Company, Gratior County,

Michigan, October 1996 (MDEQ, 1996).

The depth of the core samples varied in length ranging from 4 to 79 inches. The samples

were segmented into 4 depth intervals: 0 to 6 ,6 to 28,28 to 51 and 51 to 71 inches. MDEQ

perfomled the chemical analyses on the samples which consisted of DDT and its metabolites

(o,p'DDD, o,p'DDE, o,plDDT), HBB, PBB, PCBs, other organics as well as percent total

volatile solids. Analysis of the data included calculating the surface-area weighted

concentrations for risk assessment purposes, and calculating volume and mass of contaminants.

The results for each of the four depth intervals is discussed below. Surficial(0-6 inch)

concentration of total DDT reached a maximum of 75 ppm and was located on the north side of

the impoundment adjacent to the park in the middle basin at Station 07. For the entire survey,

the maximum concentrations of total DDT were found in the second depth interval, 6-28 inches.

The area of highest contamination in this layer was located on the south side of the impoundment

along the shoreline in the middle basin at Station 01 with total DDT concentrations of 1,175

ppm. In the 28 to 51 inch layer the levels of total DDT concentrations were lower with a

-

) maximum total DOT concentration of 54.9 ppm. Results from the sediment layer 51 inches and

greater showed that very few sediment cores penetrated to depths greater than 5 1 inches. There

is evidence of DDT contamination in this layer, but at low levels. Results are summarized in

Table 2.2-6.

Table 2.2-6: Total DDT Concentrations per Depth Interval (1996 Data)

\v'

I Analyses of PBB and HBB showed that the maximum concentrations were found at

Station 1, along the south shoreline in the middle basin, in the second interval, 6 - 35 inches. The

maximum concentration for PBB and HBB were 2.9 ppm and 240 ppm, respectively. These

levels are significantly lower than those detected in the 1981 survey.

Five sediment grab samples were collected by MDEQ in the Pine River between the St.

Louis dam and the confluence with the Chippewa River. Significant amounts of total DDT were

not found in sediments below the St. Louis dam. The results are summarized in Table 2.2-7.

Depth Interval (in)

0 - 6

6 - 28

28 - 51

51+

Max. Conc. (pprn)

75

1,175

54

0.4

Avg. Conc. (ppm)

9.2

101

12

0.38

Min. Conc. (ppm)

0.2

0.2

0.2

0.33

-

Table 2.2-7: Total DDT Concentrations in Sediment below St. Louis Dam

In July of 1997, the U.S. EPA and MDEQ conducted a second sediment sampling in the

Pine River and the Impoundment area. The survey was intended to supplement the May 1996

survey and provide additional information regarding the nature and extent of the DDT

contamination in the Pine River. A total of 28 cores and 3 grabs were collected and partitioned

into 0 to 6 , 6 to 30,30 to 54 and 54 inches to refusal depth intervals. A total of 77 samples were

analyzed for total DDT contamination and total organic carbon (TOC). All sample locations are

identified on Figure 2-10. On the last day of the survey the sampling equipment malfunctioned;

therefore only grab samples (surficial) were obtained instead of core samples in the lower basin

at Stations 27,28,29,30, and 31.

As shown in Table 2.2-8, sediment total DDT concentrations ranged from 1.3 to 32,600

ppm. Of 77 samples, none of the samples indicated total DDT concentrations less than 1 ppm,

44 were between 1 and 10 ppm, 14 were between 10 and 50 ppm, 3 were between 50 and 100

Location

McGregor Road

downstream of Bagley Road

Magrudder Road

9 Mile Road

Meridian Road

Total DDT (ppm)

0.566

0.117

0.258

0.143

none detected

' ppm, 14 were between 100 and 1000 wm, and 7 samples were greater than I000 ppm total DDT.

As a result of the July 1997 sediment survey, several observations and conclusions can be

made regarding the nature and extent of DDT-contaminated sediment in the Pine River. In the

surfical samples, 0 to 6 inches, the maximum total DDT concentration was 229 ppm with a mean

value of 28.4 ppm. Total DDT concentrations were higher in the 6 to 30 inch and 30 to 54 inch

depth intervals. A maximum total DDT concentration level of 32,600 ppm was detected in a 6 to

42 inch depth level with a mean value of 1,485 ppm. At depths below 54 inches, concentrations

ranged from 822 ppm, with a mean value of 129.8 ppm. Concentration values increase at the L

middle depth interval and decrease for the deeper depth intervals. This is in agreement with the

results of the May 1996 sediment survey.

I Table 2.2-8: Total DDT Concentration per Depth Interval (1997 Data)

Depth Interval (in.) Max. Conc. (ppm) Avg. Conc. (ppm) Min. Conc. (ppm) I

The average TOC content of the impoundment surface sediment was 3.1 percent. The

average TOC content of subsurface samples was 3.5 percent.

54- 112 * The maximum concentration was found in a sample collected from 6 to 42 inches.

822 130 2.4

The sediment surveys described above represent 84 sample locations and 225 discrete

samples. Based on the data obtained from the sediment surveys several observations can be

made. First, the location of the maximum total DDT concentrations were consistently found in

the sediment depth interval ranging from 6 to 42 inches. This area includes the Impoundment

from the Site plant jetty to the Mill Street bridge in the middle basin.

Results from all sediment surveys indicate that the levels of total DDT in the Pine River

and the St. Louis Impoundment are extremely high. Analyses from the 1980, 1981, 1996, and

1997 data show that the concentration levels, as a whole, have not decreased over time.

Fish tissue samples were collected from the SLI and below the St. Louis dam by the

MDEQ in 1983, '85, '89, '94, '95 and '97. Generally, fish tissue samples were analyzed for

DDT, DDE, DDD and PBB. This summary of fish data focuses on trends in skin-off filet (Fs)

carp samples since this was the only sample type consistently collected. Table 2.2-9 summarizes

the maximum, average and minimum concentration of total DDT in skin-off filet samples of

carp. Table 2.2-10 illustrates specific sampling factors that may explain variability in the data

and highlights data trends.

Tables summarizing results from all fish sampling are located in Appendix A. For

Human Health risks associated with eating fish, see section 2.3 of this report.

) Table 2.2-9: Skin-off Filet Carp Samples

* Fish collected in 1983 were not analyzed for DDD and DDE ** 34.57 ppm total DDT is the average concentration for fish collected in the SI.I,26.82

ppm total DDT is the average concentration for fish collected below the St. Louis dam.

Each of the congeners that make up total I>D1' (I)I)D. 1)DE and DDT) have two

components. ortho para ("op") and para para ("pp").

In order to be as consistent as possible when comparing fish data, the trend for carp

collected below the St. I.ouis dam will be compared separately from carp collected in the SI.1.

Several interesting observations can be made from the information presented in Table 2.2-10.

Fish were collected from below the St. Louis dam in 1983, 1985, 1994 and 1997. However, in

1983 carp were analyzed only for pp DDT so data from this year cannot be compared for trends

of pp DDE: and pp DDD. What is noteworthy for the 1983 data is the level of pp DDT recorded

(0.08 pprn) is consistent with levels of pp DDT found in other collection years. Levels of pp

DDE. pp DDD and pp DDT increase significantly hetwe(:n '85 and '94 with levels in '97 being

similar to '94. The average weight of fish collected increases over the collection years with the

average % fat increasing with weight (but not proportionally). The increased weight of the fish

collected might indicate older fish, possibly accounting fbr some of the increase in contaminant

concentration. Older fish would be expected to bioaccurnulate greater concentrations of

contaminants.

In 1985 all eight carp samples obtained below the dam exceeded the Michigan

Department of'f'ublic f Iealth (MUPH) and Federal Food and Drug Administration (FDA)

tolerance level of 5 ppm. 8 of the I0 carp samples collected in 1994 and all 12 of the carp

samples collected in 1997 (below the dam) exceeded MDPH and FDA tolerance level of 5 ppm

for total I)IYI' in fish.

Fish were collected Srom the SI,I in 1989, 1995 and 1997. Contaminant level trends for

carp collected in the SI.1 are even more alarming than fiom below the dam. Levels o f p p [)Of;,

) pp DDD and pp DDT increase significantly between 8 9 and .95 and then increase significantly

again between 1995 and 1997. The average weight of fish collected again increases over the

collection years, as with the carp below the dam, however the average % fat is similar for 1989

and 1995 and slightly increases in 1997. The increased weight of the fish collected might

indicate older fish possibly accounting for some of the increase in contaminant concentration.

However, since the % fat does not significantly increase with weight it is less likely this is the

reason for the significant increase in contaminant concentrations. The most disturbing trend for

carp collected in the SLI is the fact that the average % fat for these fish was consistently less than

half the average % fat of carp collected below the dam, even when the average weights were very

similar. For example, in 1997 fish collected below the dam exhibited average weight of 2819

grams, fish in the SLI 3099 grams. Fish below the dam had an average % fat of 6.56%, fish in

I the SLI 3.1 5% fat. Comparing weights and % fat for 1985 and 1989 and again for 1994 and

1995 indicate this is not an anomoly for 1997. In 1989 four of ten carp samples exceeded the

MDPH and FDA tolerance level of 5 ppm. Six of ten carp samples collected in 1995 and six of

eight of the carp samples collected in 1997 (in the SLI) exceeded the 5 ppm tolerance level for L

total DDT in fish.

It is difficult to draw conclusions from the data due to variabilities (weight, age, % fat,

number of samples collected, etc.), however, what is clear is that carp in the SLI and below the

St. Louis dam show a significant increase in contaminant concentration after 1985 and no

decrease between 1995 and 1997. Carp are bioaccumulating significant levels of total DDT and

there are no indications, from the 14 years of data, of a downward trend. If any conclusion could

be drawn it would be that contaminants in sediments continue to be increasingly bioavailable to

fish. Fish in the Pine River are highly contaminated and will continue to be if no remedial

action is taken at this site.

Fourteen water samples were collected in June, 1980 from the Pine River between the

Cheeseman Road bridge and the St. Louis Municipal wastewater treatment plant outfall to

document the contamination of the Pine River. These samples were collected in one gallon glass

containers using a battery operated vacuum pump with teflon tubing. The samples were tested

for PBB, HBB, DDT and its analogs, and subjected to a limited organic scan.

The Pine River water samples did not contain measurable concentrations of HBB, PBB,

or DDT analogs. Elutriate testing under laboratory conditions showed that these contaminants

are bound tightly with the sediment and do not readily desorb and solubilize from the sediments

to the water. Only a small amount of p,p-DDT was detected in the water from the static phase of

the testing. The amount desorbed was less than 0.01% of the amount present in the sediment.

Two water samples, RWS-6-01 and RWS-6-02, did contain 3.5 ugll (ppb) and 2.7 ug/l

(ppb) methoxychlor, respectively. The origin of this compound in the samples is not known.

In October of 1992 water sampling was again conducted. The City of St. Louis had a

water quality study completed in the area surrounding the St. Louis dam. Six samples were

collected by Ayers, Lewis, Norris, & May, Inc. Three of these samples were taken above the

dam, and three samples were taken below the dam. The samples were tested and reported as two

composites, above and below the dam.

The laboratory results showed levels of total DDT, other hydrocarbons and pesticides,

and BTEX for the two composites to be below the method detection level. insignificant traces of

heavy metal were found, however most of these were at or below the detection level.

This risk analysis focuses on current human health risks from the contamination at the

Velsicol Chemical Company Site, St. Louis, Michigan. The risk assessment is based upon data

reported in the October 1996 staff report entitled "Status of the St. Louis lmpoundment in the

Vicinity of the Former Velsicol Chemical Company, Gratoit County, Michigan." The purpose of

this analysis is to identify the human health risks at the site. In addition, this assessment will

identify any data gaps and the resulting assumptions required to assess risk.

This streamlined risk assessment was updated using 1997 sediment and fish data. The

addendum is located in section 2.3.10 'L

In addition to the 1996 staff survey, contaminant levels in Pine River fish have been

monitored since 1974. Recent tissue analyses indicate an upward trend in the concentration of

total DDT in fish inhabiting the St. Louis Impoundment and downstream Pine River. The

presence of these bioaccumulative contaminants has resulted in the issuance of a no consumption

advisory for all species of fish in the Pine River from St. Louis to the confluence with the

Chippewa River. This advisory has been issued annually since 1974 and is due to elevated

concentrations of both DDT and PBB in fish tissue in excess of FDA guidelines. According to

the USEPA EJational Fish Tissue Data Repository (1995), this is the only waterbody in the nation

which has a fish consumption advisory in effect due to the presence of these two contaminants.

This assessment relies upon fish and sediment data from MDEQ taken in 1989 and 1995

(Table 2.3-1). During the period from 1985 to 1994, mean DDT concentrations in fish collected

downstream of the St. Louis impoundment have increased significantly. The increase in total

UDT concentrations in fish tissue is also apparent in collections made in 1989 and 1995 from

within the St. Louis impoundment. The fish tissue (and sediment) data indicate that the burial of

the contaminated sediments contained within the St. Louis impoundmetit has not been as

extensive as predicted and contaminants continue to accumulate in fish tissue.

The sediment data is presented as 0-6" and 6"-35". While it is understood that waders

and swimmers are unlikely to be exposed to sediment at 35" of depth, it is also believed that

exposure will occur at depths greater than 6". Therefore, both sediment depths are used in the

calculation of risk. For this risk assessment, the maximum level of each contaminant as found at

each sediment depth was used. These maximum levels of contaminants did not necessarily occur

at the same sampling location (Table 2.3-2).

This assessment combines the data for DDT and its breakdown products, DDD and DDE,

) and refers to them collectively as DDT.

Table 2.3-1 Fish Data

Fish

Largemouth Bass

Crappie

Table 2.3-2 Sediment Data (1996 Data) I Z I

1989 average

0.08 (PBB) & 3.7 (DDT)

1 car^

1995 average

Not Done

0.14 (PBB) & 5.7 (DDT) 0.8 (PBB) & 9 (DDT)

0.09 (PBB) & 9.5 (DDT)

\

2J.A Exposure Pathways

16 (DDT)

Contaminant Maximum Concentration (ppm) Depth Sample Location - P

DDT 75 0-6" 7

PBB

HBB

DDT

PBB

HBB

The site is located next to residential as well as recreational areas. There are docks and

other indications of easy access to the river and the river sediment. The physical setting of the

site is such that there are several possible pathways of exposure to the contamination in the

sediment: dermal contact, ingestion of contaminated surface water or sediment, and

consumption of fish contaminated by sediment. The sediments are contaminated with PBB,

31

2.1

32

1,175

2.9

240

0-6"

0-6"

6"-28"

6"-35"

6"-35"

20

2

1

I

I

DDT and HBB, all hydrophobic organic compounds that will partition to organic material. This

risk analysis assumes that the most significant exposure will be via contaminated sediment,

where virtually all of the chemicals of concern (COC) are located, and not the surface water.

This assessment also addresses the risk from dermal contact with contaminated sediments. It is

assumed that incidental ingestion of sediment will contribute negligibly to the risk from the site.

PBB and DDT are hydrophobic compounds which bioaccumulate in organisms and

biomagnifj in the food chain. There are fish (largemouth bass, black crappie and carp) in Pine

River which are contaminated with both PBB and DDT. Consumption of these contaminated

fish is likely to drive risk at the site.

This assessment does not consider exposure to floodplain soils. In order to characterize

the exposure from consumption of contaminated fish, two exposure scenarios were developed:

average or sport fishers which represent a central tendency estimate of exposure, and subsistence

fishers which represent high-end exposure. The assumptions used to estimate these exposure

scenarios ar? listed in the summary table. These two scenarios were developed to represent the

range of possible exposures at the site. The area around the site is residential and there may be

subpopulations of people who catch and consume fish from Pine River on a regular basis.

Two exposure scenarios were also developed in order to characterize dermal exposure to

contaminated sediments. The assumptions used to estimate these exposure scenarios are listed in

Table 2.3-5. Briefly, the assessment assumes that all contact will be occurring to the highest

level of each contaminant (as opposed to the surface weighted average). For the central tendency

estimate, this concentration is taken from samples in the top six inches. The high-end exposure

scenario assumes that exposure will occur to the highest concentration of contaminant found at

*

- .....,

) the next level of sedimentation (approximately 6-28 inches). It is likely that an individual who

spends time wading and playing in the sediment will come into contact with primarily the top six

inches, but also to the more contaminated sediment that is located at depth. Both scenarios

assume that an adult will be exposed to the sediment for 10 dayslyear for 20 years and that a

teenager will be exposed to the sediment for 100 dayslyear for 10 years. Absorption of DDT is

assumed to be 0.38, absorption of PBB is assumed to be 0.1, and absorption of HBB is assumed

to be 0.1.

An important sub-population of potentially exposed individuals are pregnant and nursing

. . women. This group is believed to be particularly at risk from exposure to DDT and PBB due to

the increased sensitivity of the developing fetus and newborn (nursing) to certain toxicological

effects of these chemicals. The noncancer assessment should be viewed with concern for this

'\

1 particlular sub-population, where toxicity information is still not complete.

Dermal Exposure Equation

Equation for estimating exposure intake to contaminants due to dermal contact with

chemicals (USEPA Risk Assessment Guidance for Superfund. 1989).

Exposure = CS X SA X AF X ABS X EF X ED X CE BW X AT

where:

concentration in sediment surface area

AF ABS EF ED CF B W AT

soil to skin adherence factor absorption exposure frequency exposure duration conversion factor body weight averaging time

osure EQU&QO

Equation for estimating exposure intake to contaminants due to incidental ingestion of

chemicals (USEPA RAGS, 1989).

Exposure = CS X IR X CF X FI X EF X ED BW X AT

where:

concentration in fish ingestion rate conversion factor fraction ingested exposure frequency exposure duration body weight averaging time

The principle source of toxicity information for use in risk assessments is USEPA's

34

Integrated Risk Information system, or IRIS IRIS values represent consensus-based information

for use agency-wide. When toxicity information has not been placed on IRIS, USEPA's Health

Effects Assessment Summary Tables (HEAST) can be used.

DDT and its breakdown products (DDD and DDE) are classified as probable human

carcinogens based on liver tumors, lung tumors and thyroid tumors in rodents. DDT, DDD and

DDE are all structurally similar. Both hepatocellular adenomas and carcinomas were observed in

six mouse liver tumor studies upon treatment with DDT. The cancer slope factor for DDT, as

obtained from IRlS (1997) is 0.34 (mg/kg-day)-'. Treatment of mice with DDD resulted in a

statistically significant increase in incidence of lung tumors in both sexes of mice when

compared to controls. The cancer slope factor for DDD is 0.24 (mglkg-day).'. DDE

administered to mice resulted in a dose-dependent and statistically significant increase in

incidence of hepatocellular carcinomas in both males and females in comparison to controls.

The cancer slope factor for DDE is 0.34 (mg/kg-day)-'.

A slope factor for assessing cancer risks assumes that cancer risk is probabilistic and any

L degree of exposure leads to some degree of risk. A slope factor relates estimated exposures to

incremental lifetime cancer risks, and therefore the result is a probability of cancer over the

background levels in the population. Therefore a risk result of 7 E-4 is equivalent to saying there

is an increase cancer risk at a rate of 7 in 10,000 people. This assessment combines the data for

DDT and its breakdown products, DDD and DDE, and applies the cancer slope factor of 0.34.

DDT and its breakdown product (DDD and DDE) have also been reported to exert non-

cancer effects. IRlS specifically calculates a Reference Dose (Rfl)) for DDT based upon liver

toxicity in rats. The RtD was based upon a study performed in adult male rats and is 0.0005

35

mglkg-day. An RfD is intended to indicate a safe level exposure, meaning that exposure at the

RfD level is likely to be without an appreciable risk of deleterious effects. To assess non-cancer

risks, a hazard index of the estimated exposure over the RfD is calculated. Because the RfD

represents a safe level, the hazard index should be one or less than one. The higher the hazard

index the higher the likelihood of adverse effects.

In addition, DDT and its breakdown products (DDD and DDE) are undergoing increasing

scrutiny for their role as endocrine disrupting compounds. As endocrine disrupters, DDT has the

potential to negatively impact the developing fetus, increase vulnerability to certain cancers, and

possibly decrease fertility. While conclusive studies have not been done in order to develop an

RfD based on these endpoints, the current evidence suggest some endocrine disrupting potential

for DDT and its breakdown products. Due to the tremendous uncertainty around this endpoint,

this risk assessment applies the R D for DDT (calculated based upon liver toxicity in adult male

rats) to the breakdown product of DDT (DDD and DDE) for which no RfD has been calculated.

Polybrominated biphenyls (PBB) are classified as probable human carcinogens based on

liver tumors in rats. Both carcinomas as well as neoplastic nodules were observed in rats treated

with PBB. The cancer slope factor for PBB, as obtained from HEAST (1995), is

8.9 (mglkg-day)-'.

PBB has also been reported to exert non-cancer effects. HEAST reports an RfD for PBB

based upon liver toxicity in rats as 7 x In addition, PBB is undergoing increasing scrutiny

for its role as an endocrine disrupting compound. As an endocrine disrupter, PBB has the

potential to negatively impact the thyroid, the developing fetus, increase vulnerability to certain

cancers, and possibly decrease fertility.

*

-

1 Hexabromobenzene (HBB) does not have a carcinogenicity assessment entered into either

IRIS or HEAST. An RfD has been calculated for HBB based upon induced serum carboxyl

esterase activity and increased liver-to-body weight ratio. The RfD for HBB is 0.002 mgikg-day.

The confidence in the RtD is low because the critical study was of shon duration, only one sex

(male) was exposed, and few definitive parameters were examined.

The hazard indices from all three chemicals can be appropriately added because of the

shared target organ of the liver.

This assessment used two sets of exposure assumptions to assess risk from fish

i consumption; in general they were developed to assess "average" fishing (central tendency) and

worst-case subsistence fishing (see Table 2.3-4). For each type of species assessed, these two

types of' fishing behaviors were assessed. The exposure assumptions used and the resulting risks

are shown in Table 2.3-4. In general, the worst-case scenario should be considered as very high- L

end exposure; the individual is getting almost all of their protein from fish, these fish are from

that area of the Pine River only, and the person is fishing in that area for their entire lives

Alternatively, the assumptions used to shape the "average" scenario are: an individual fishing a

few months a year, getting only a fraction (25%) of their fish from the Pine River, for a period of

9 years. The average case then could therefore represent a significant portion of the population.

The assessment also assesses risk from dermal exposure to sediment (Table 2.3-5). Two

exposure assumptions were used: a central tendency and a reasonable maximum. The central

~~ ~ ~ -. 1;' i~ - ~ ~ - . p~~ ~

.

tendency represents exposure of the feet to the highest concentration of contaminant found in the

top six inches of sediment. The reasonable maximum represents exposure of the feet and legs to

the highest level of contamination found in the next layer of sediment (6-28").

The cancer risk from ingesting approximately one fish meal per month from the site

(recreational) was approximately 6 x lW5 and the hazard index was less than one (Table 4). For

subsistence fishermen (approximately one meal per day from the site) the cancer risk was

approximately 1 x 1W2 and the hazard index was approximately 124.

The central tendency cancer risk from dermal exposure to contaminated sediments was 7 w x and the HI was less than one (Table 5). The reasonable maximum cancer risk from dermal

exposure is 7 x lW4 with an HI of 28. The presence of DDT in the sediment is the risk driver for

this exposure pathway. Both of these calculations use the maximum level of contamination

detected at either 0-6" or 6"-28" respectively. As such, this risk calculated from this exposure

pathway is likely to be overestimated risk.

When the two exposure pathways are added together the result is a central tendency

cancer risk of 7 x 10.' and a HI of less than 1 . The reasonable maximum cancer risk is 1 x 10.'

with an HI of 152. Risk occurs primarily through fish consumption. The risk levels are of

particular concern because they do not consider the potential endocrine disruption that is

believed to be occurring from exposure to these chemicals.

-

) Table 2.3-3 Summary of Fish Consumption Risks

Noncancer Risk

0.2

68

1.2

194

0.4

I I I

Scenario

I recreational* - bass

2 subsistence' - bass

3 recreational -crappie

4 subsistence - crappie

5 recreational -carp

6 subsistence - carp

Exposure Parameter

largemouth bass 1989 (no 1995 data) mean concentration 20 giday 25% from Pine River 9 years

largemouth bass 1989 (no 1995 data) maximum concentration 130 glday all from Pine River 30 years

crappie 1995 mean concentration 20 giday 25% from Pine River 9 years

crappie 1995 maximum concentration 130 giday all from Pine River 30 years

carp 1989 PBB & 1995 DDT mean concentration 20 giday 25% from Pine River 9 years

carp 1989 PBB & 1995 DDT maximum concentration 130 giday all from Pine River 30 years

Increased Cancer Risk

2 x 10.'

8 x io"

9~ 10'

I x lo"

6~ 10'

I x 10.'

Table 2.3-4 Summary of Dermal Exposure Risks

Given the relative quality of the fish data, the uncertainty in this assessment comes

mostly from exposure assessment and the toxicity values. While assessing exposure cannot be

exart, an explicit attempt was made to capture the range ot'the possibilities.

The classical risk assessment calculates risk over a long period of time and averages

exposure over that time. The assumption behind this is that repeated small levels of exposure

can result in a risk that is cumulative. When chemicals act as endocrine disrupters, however,

they can exert their effect on the developing fetus during a very short window of time (for

example weeks 8 through 10 of gestation). Thus, a pregnant woman who is exposed to a

contaminant just once during that window of time risks the development of her child. This

narrow window of exposure and potential health effect is not quantitatively considered in this

risk assessment. As a consequence, this risk assessment likely underestimates risk from the site.

Noncancer Risk

0.3

28

Scenario

1 central tendency

2 reasonable maximum

Exposure Parameter

0-6" exposure exposed feet adherence = 0.2

6-28" exposure exposed feet and legs adherence = l

Increased Cancer Risk

7 x 1W6

7 x 10.''

The fish sampled at the site are contaminated with DDT and PBB (both of which have

been identified as endocrine disrupters). The level of contamination of the fish at the site does

not appear to be decreasing (1995 compared to 1989) but rather appears to be increasing. The

site is surrounded on one side by a residential neighborhood and on the other by a park, making

frequent exposure likely. The central tendency cancer risk from the site is 7 x 10.' and the HI is

,V less than 1. The reasonable maximum cancer risk is 1 x with an HI of 152. These results are

of particular concern because they do not consider the potential endocrine disruption that is

believed to be occurring from exposure to these chemicals. As a consequence, this risk

assessment likely underestimates risk from the site. I

229 References

U.S. EPA. 1989. Risk Assessment Guidance for Superfund: Volume I- Human Health

L Evaluation Manual.

U.S. EPA 1992. Dermal Exposure Assessment: Principles and Applications.

U.S. EPA. 1993. Superfund Standard Default Exposure Factors for the Central Tendency and Reasonable Maximum Exposure. Preliminary Review Draft.

LUQ Addendum to 1996 Baseline Risk Assessment

2.3.10.1 Scope and Purpose

The purpose of this addendum is to update the baseline risk assessment (Section 2.3) with

the more recent sediment and fish data obtained in 1997.

This analysis relies strongly on the baseline risk assessment to provide background,

discuss exposure and toxicity information in more detail, and give more, information on

calculations. The reader is strongly encouraged to use the baseline risk assessment as a reference '*I*

and parent document to this analysis.

All exposure assumptions used in the baseline are carried through in this analysis. The

only difference in this section is that an additional fish ingestion pathway was added to find a

reasonable maximum estimate within the bounded estimates done in the baseline risk assessment.

2.3.10.2 Exposure Consideration3

DDT and its breakdown products are found mainly in the sediments of the Pine River,

which dictates how people can be exposed to DDT at this site. Given the location of DDT, the

chief threat is believed to be the food chain, from consuming contaminated fish from the site.

People may also come into contact with the sediments from direct exposure to their skin, by

either wading or light recreational-type contact. While this may not occur frequently, it is

thought to occur to some degree given the very close proximity of many homes to the River and

lack of any appreciable barriers of any type separating backyards from the River (including

42

) vegetation, presence of any banXs, dock faces, etc,). Other routes such as air or ingestion are

thought to be minimal and insignificant compared to these other routes, because oithe low level

volatility of DDT and it's strong partitioning to sediment. They are not assessed further in this

document.

Exposure scenarios are defined by the exposure assumptions used, to view all exposure

assumptions used in all scenarios please see Table 2.3-5. In this analysis, the critical

assumptions that define the scenarios are:

* ingestion rate (how many grams a day of fish people consume),

L fraction ingested (how much fish consumed comes from Pine River)

* type of fish consumed (sport f ish vs. boaom feeding fish)

A study done by West et al. on Michigan anglers provides useful data on ingestion rates 1

for the various scenarios. For the lower bound estimate, or sport fishing scenario, the 50th

percentile ingestion rate from the West study was used (a daily average of 20 grams per day).

For the reasonable maximum exposure pathway (RME), the 951h percentile ingestion rate from

L the West study was used (a daily average of 75 grams). Given the quality and specificity of the

West study, there is a good deal of confidence that these exposures are reasonable and do occur

for some portiotl of the population at the site. For the subsistence scenario, which should be

considered to be an upper bound estimate or worst case scenario, a study of a three day

maximum fish consumption was used instead of West data.

EPA made assumptions regarding the fraction of Pine River fish ingested for each

consumption scenario. For the lower bound or sport fishing scenario, EPA assumed that 25% of

the fish consumed comes from the Pine River. In the RME scenario, EPA assumed that 50% of

43

fish consumed comes from the Pine River, and for the subsistence scenario EPA assumed that all

fish consumed comes from the Pine River.

TABLE 2.3-5 Exposure Assumptions

2.3.10.3 New Data

The recent sediment data collected in July 1997 and fish data collected in October 1997

were assessed to estimate current risks of consumption of contaminated fish and dermal risks. In w

other sections of this document, the sediment and fish data are discussed in detail, and should be

consulted for detailed information

2.3.10.4 Toxicitv

Both cancer effects and noncancer effects of DDT were assessed. Toxicity of DDT is

discussed in the baseline risk assessment. The noncancer effect being assessed here is liver

) lesions

2.3.10.5 Risk Character~zat . .

l a

sh COIUWQLW r~sks - 1997 data

Risks were estimated by using the 1997 fish data, both the smallmouth bass and carp data

were used, along with the exposure assumptions for each scenario described in Table 2.3-5

(sport, RME and subsistence). A summary of the risks for each species for each exposure L

scenario is shown in Table 2.3-6.

TABLE 2.3-6 Current Risks from Fish Consumption

Table 2.3-6 indicates that risks are within or exceeding the target risk range of

E-4 - E-6 for all exposures and all species. Even consumption of bass, which is frequently much

ICancer 1 sport I RME I subsis. ]Hazard Isport1 RME 1 subsis.

less contaminated than other fish, is of significant concern. The RME estimate for both species '-.-

shows that for any combination of fish caught, risk increases and even recreational fishing with

only 50% coming from this site is not without risk.

0.21 1 1.7 1 22.6 0.63 1 6 1 95

Smallmouth bass Carp

2.3.10.5.2 Current Dermal Risks

3.6 E-05 1 3 E-04 1 4 E-03 1 E-04 I 1 E-03 1 1.6 E-02

Risk of cancer via dermal contact with the sediments was estimated for a typical

recreational exposure using concentrations in the top 6 inches of sediment and a reasonable

45

maximum exposure, using the maximum at subsurface levels of sediment; again using the same

exposure assumptions used in the baseline risk assessment. Table 2.3-7 shows current risks from

dermal exposures using 1997 data.

TABLE 2.3-7 DERMAL CANCER RISKS USING 1997 DATA

Typical (0-6 in. sediment)

2.OE-05

RME (max at subsurface)

2.OE-02 ,

'W

j .&I

U J Introduction

There are two main goals of an ecological risk assessment (ERA): 1 ) to determine

whether harmful effects are likely for wild animals or plants (referred to as "significant risk");

and 2) if there is risk, to calculate a protective cleanup level that would reduce the risk to wild

animals or plants. Only wildlife is considered, domesticated animals or plants are excluded from

ERA. The process for performing an ERA is described in the Superfund guidance for ecological

risk assessment (USEPA 1997). The main steps of an ERA are outlined below.

An initial step of an ERA is to decide which components of an ecosystem (the sum of all

the living organisms and the physical factors in a particular area) should be protected, that is,

1 which species should be the focus of the ERA. This is different from human health risk

assessments in which the species is predetermined (human). The decisions of what to protect and

how to measure it are made in the Problem Formulation step of the ERA.

Problem formulation begins with development of a conceptual model, which is a

representation of how the particular contaminants at a site are expected to behave in the

environment. The conceptual model is based on fate (e.g., does a contaminant break down in the

environment or is it persistent?) and transport (how does a contaminant move through the

environment and where does it end out?). The conceptual model is used to narrow attention to

the animals andlor plants likely to be exposed to the contaminants at the site. In risk assessment

language, the species that may be exposed to contaminants are called "receptors".

It is not possible to study every species that is potentially at risk at a site. In the Great

Lakes region there are some 75 species of amphibians and reptiles, 80 species of mammals, over

200 species of breeding birds (and a nearly equal number of nonbreeding and accidental species),

a couple of hundred species of fish, several thousand species of terrestrial plants, 20,000 species

of insects, and so forth. The purpose of the problem formulation is to focus attention on a few

species or groups of species that are appropriate for answering the question of whether an

ecological risk exists at the site.

Different terms are used to refer to what should be protected (assessment endpoint) and

W what will be studied (measurement endpoint). Assessment endpoints are explicit expressions of

the environmental value that is to be protected (USEPA 1997), that is, an overall explanation of

why anyone should be concerned about potential ecological impacts at a site. Measurement

endpoints are measurable ecological characteristics that are related to the assessment endpoints,

and may include measures of effects (caused by a contaminant) and/or measures of exposure (to a

contaminant) (USEPA 1997). In other words, what will actually be investigated to determine the

level of risk.

Assessment and measurement endpoints may be one and the same, or different but related w

to each other. For example, protection of fish production could be an assessment endpoint. A

possible measurement endpoint would be to perform a field study of fish productivity at the site

(measurement and assessment endpoints are the same). Another approach would be to measure

the impact of contaminants on benthic invertebrates (measurement endpoint), which are related

to fish productivity (assessment endpoint) because benthic invertebrates (the insects and other

small creatures that live on the bottoms of streams and other bodies of water) form the base of

) the food chain that supports freshwater fish populations. In this case, effects on benthic

invertebrates are assessed for the ERA, but the reason for doing so is concern over potential

impacts on fish.

The next steps are Characterization of Ecological Effects and Characterization of

Exposure.

In Characterization of Ecological Effects, the potential adverse effects of the

contaminants are described. The information is taken from literature of field and laboratory

- studies performed for the particular contaminant, and, if available, from investigations of

ecological impacts at the site. An important part of this section is to calculate the dose that is

associated with adverse effects, that is, how much of a contaminant must be absorbed to cause a

toxic effect?

1 Characterization of Exposure summarizes what is known of the extent of contamination

at the site, and the measured or estimated uptake of the contaminants by the ecological receptors.

The next step is Characterization of Risk in which the amount of exposure of the

ecological receptors to the contaminants is compared with the dose associated with adverse L

effects to determine whether the contamination at the site presents a potentially significant risk.

If risk is indicated for the site, back-calculations are performed to determine ecologically

protective cleanup goals, such that exposures would be reduced below levels of concern.

An Uncertainty section is included in all risk assessments to describe the uncertainties

associated with the assumptions, extrapolations, and limitations of knowledge, and the possible

effects of these uncertainties on the outcome.

DDT and its breakdown products DDE and DDD (collectively referred to as DDTr) are

poorly soluble in water, but highly soluble in lipids (fats and oils). The scientific term is

lipophilic (fat loving). This means that DDTr do not dissolve well in water and, in aquatic

environments, are found mainly in sediments. Within the sediments, DDTr attach mainly to

organic matter (remains of plants and aquatic organisms). DDTr are also readily taken up by \rl

living organisms and stored in their fat. Exposures to predators mainly occur through food chain

transfers, that is, by feeding on prey that have accumulated DDTr in their tissues.

Another important property of DDTr is their persistence in the environment and in living

organisms. The main exception is that DDT is metabolized by living organisms to DDE, which

itself is very stable. Chemicals that are both persistent and lipophilic are likely to increase in

concentration as they move up through a food chain, a process termed "biomagnification". There

is some scientific disagreement over the underlying mechanisms, but a common observation is .-/

that predators have higher body burdens of DDTr than their prey.

These principles are reflected in the conceptual model in which DDTr in sediments are

taken up by detritus (the decaying remains of plants) andor by benthic invertebrates; are

transferred to fish mainly through feeding relationships, but partly by incidental sediment

ingestion and direct partitioning from sediment to water to fish; and lastly are transferred to fish-

eating birds (the formal term "avian piscivore" is not used here) through feeding relationships.

) Conceptual Model:

DDTr in sediments -* detritus and/or benthic invertebrates -* lish -, fish-eating birds - surface water and/or sediment ingestion -1

The following assessment endpoints are selected for the Site:

1) Protection of fish-eating birds from adverse reproductive effects, and

2) Maintenance of benthic invertebrate diversity and productivity to ensure a high quality forage base for the support of fish populations.

The assessment endpoints reflect two known potential adverse environmental effects

associated with DDTr: reproductive impairment in birds related primarily (but not exclusively)

with eggshell thinning (Peakall 1993), and lethal effects on benthic invertebrates (Edwards, et a1 I

1964).

2&!.2 Measu -nt En-

Two measurement endpoints are selected:

1) Calculation of doses to great blue heron, Ardea herodias, (as a representative fish-eating bird) based on measurements of whole-fish DDTr levels for comparison with toxicological studies of reproduction in birds.

Great blue heron is chosen because it is widely distributed in Michigan and possibly breeds in

Gratiot County (Brewer, et al. 1991). Kingfisher is another potential endpoint, but herons are

closer in size to bald eagle and osprey, which have been sighted along the Pine River and

therefore are potential receptors. Eagles and osprey are not directed assessed because they

apparently only occasionally forage in the contaminated zone. An aerial survey discovered no

eagle nests along the Pine River (Lisa Williams, USFWS, personal communication, 4/8/98).

Remedial decisions based on risk reduction for herons should be protective of eagles and osprey

as well, even if their nesting populations expand into Gratiot County.

2) Comparisons of sediment DDTr levels with threshold concentrations for adverse effects on benthic invertebrates as determined at other sites.

The preferred approach for the second measurement endpoint would be to perform site-

specific benthic invertebrate s w e y s coupled with sediment toxicity testing. Since these studies

have not been performed at the Site, comparisons are made with the results of these types of

studies at other DDT sites lo indicate the likelihood of adverse benthic effects. This is equivalent

to a preliminary (also called screening or tier I) ecological risk assessment and, as such, is

provided for discussion and comparison with the results of the first measurement endpoint, but

will not be used to set remedial cleanup goals.

2.4.3 C-on of Ecol . . -1 Effects

2.4.3.1 Fis-

DDE has been associated with reproductive impairment in a variety of fish-eating bird

species in both lab and field studies (Peakall 1993). The best demonstrated effect is eggshell

thinning, which has been shown to be logarithmically related to egg DDE residues (Blus, et al.

') 1972). While some studies have identified other contaminants. such as PCBs and mercury, as

causal agents instead of DDE (e.g., Scott 1977), most studies show stronger correlations between

eggshell thinning and DDE than with other contaminants (e.g., Haegele and Tucker 1974;

Wiemeyer, et al. 1993). The pattern of eggshell thinning also differs for DDE in comparison

with other contaminants. Eggshell thinning occurred more quickly and persisted longer

following single oral doses of DDE as compared with a variety of other contaminants, including

PCBs, which exhibited transient effects on eggshell thickness (Haegele and Tucker 1974).

Adverse effects on eggshell thickness have occurred as long as 1 1 months after cessation of DDE

exposure (3-month initial exposure period) (Haegele and Hudson 1974), which indicates even

intermittent exposures may be of potential concern.

Field studies have shown population declines in a variety of fish-eating bird species ' associated with eggshell thinning of 15-20% (Anderson and Hickey 1972; Peakall 1993). DDE

disrupts calcium transport from the hen to the developing egg (across the eggshell gland

mucosa), depriving the process of eggshell formation of one of its main ingredients (Lundholm

1987). Thinner eggshells are prone to breakage and the subsequent disappearance of eggs from L

nests (Porter and Wiemeyer 1969; Lincer 1975).

The adverse effects of DDE are not necessarily restricted to eggshell breakage, for

example, in field studies of bald eagles, some adverse impacts on production of young occurred

at egg DDE concentrations lower than the threshold for a 15% decline in eggshell thickness

(Wiemeyer, et al. 1993). Additional adverse effects of DDE may include increased embryo

mortality independent of eggshell cracking (Heath, et al. 1969; Fox 1976) and increased post-

hatch mortality of chicks (Haegele and Hudson 1973). The latter effect may be related to

- . changes in parental nesting behavior (Haegele and Hudson 1973), possibly correlated with DDE

or DDT-induced alterations in brain neurotransmitters (Heinz, et al. 1980). DDE and DDT have

been shown to adversely impact the thyroid gland (Jefferies and French 1971, 1972), which,

because of its important role in hormonal regulation, could result in multiple adverse effects.

DDT has also been associated with eggshell thinning and hatchling mortality, but with

less than half the potency of DDE. The adverse reproductive effects of DD'T may result from

post-ingestion metabolic conversion to DDE. DDD was associated with reproductive

impairment in the same study, but not with eggshell thinning (Heath, et al. 1969).

Susceptibility to DDE-induced eggshell thinning varies greatly among species - raptors

(e.g. falcons, osprey, eagles) and fish-eating birds are most sensitive, waterfowl are intermediate,

while gallinaceous birds (e.g.,chicken, quail, pheasants) are "almost completely insensitive"

(Walker. et al. 1997). Differences in selection of test species are related to the disagreements

regarding the role of DDE in eggshell thinning discussed earlier.

Toxicological studies of DDE and eggshell thinning have been criticized for confounding

apparent DDE effects with calcium deficiencies in the diets of the test organisms. Calcium

deficiency is another cause of eggshell thinning, and, conversely, calcium supplements can

suppress eggshell thinning in DDE trials. A variety of other agents may also induce eggshell

thinning (Edwards 1992). However, similar regressions between kestrel egg DDE residues and

eggshell thinning were demonstrated in a comparison of laboratory experiments and studies of

eggs collected from wild populations (Lincer 1975; Peakall 1993). This demonstrates that DDE-

induced eggshell thinning is not a laboratory artifact. Also, the presence and amount of DDE in

the egg membranes of archived peregrine falcon, Falco peregrinus, eggs correspond to the onset

) and severity of eggshell thinning (the eggs wen collected between I933 and 1948. before and

after the introduction of DDT) (Peakall 1993).

Laboratory studies on the reproductive effects of DDE were not located for heron or

kingfishers, two potential fish-eating birds at the Site.

Field studies were located for two heron species (great blue heron and black-crowned

night-heron, Nycticorax nycticorar) that demonstrated high rates of accumulation of DDE

residues in eggs, and inverse relationships with eggshell thickness (Vermeer and Reynolds 1970;

- King, et al. 1978; Henny, et al. 1984). While great blue herons appear to be less sensitive to

DDE than other fish-eating birds (Keith and Gruchy 1972), both great blue herons and black-

crowned night herons were among the species that exhibited eggshell thinning in wild

populations in comparisons of eggs collected before and after the introduction of DDT (Anderson

J and [Hickey 1972).

Egg breakage is naturally higher for herons than for most other species, which is

ccmpensated for by persistent re-laying of eggs. This behavioral trait may protect heron

populations from the effects of DDE-related eggshell thinning compared to species that do not L

lay additional eggs following breakage (Prestt and Ratcliffe 1972). However, field studies have

shown associations between elevated DDE levels in black-crowned night heron eggs and

increased egg cracking, accompanied by decreased clutch size, young fledged per nesting pair,

and percentage of successful nests. The productivity of the most contaminated colony was below

the level required for population maintenance (Henny, et al. 1984), which indicates that heron

populations may be vulnerable to the adverse effects of DDE despite their egg re-laying behavior.

The sensitivity of kingfishers to DDE is unknown. Kingfisher, Megaceryle alcyon,

eggshell thickness index was reduced 8% in a comparison of eggs collected in Ontario before and

after the introduction of DDT (Fox 1974). This level of thinning would not be expected to cause

problems in species such as eagles or falcons, but is not known how much eggshell thinning can

occur in kingfishers before they begin to suffer reproductive impairment. Kingfishers have

smaller and more fragile eggs than the species used for the majority of DDT studies, so the

response to thinning may also differ from those of the well-studied species. No field or

laboratory studies were located that directly investigate the reproductive effects of DDT or DDE

on kingfishers.

Unfortunately, the heron field studies cannot be used to estimate risk at the St. Louis

Impoundment, because they do not have information on the dose of DDEIDDT to the birds (the

amounts ingested by the herons). Dose information is necessary to extrapolate the results of one

stcdy to a different arealsituation with different contaminant levels.

The toxicity reference values (TRVs), critical values above which adverse effects are

expected, are derived from a study of DDE-induced eggshell thinning in American kestrels,

Falco sparverius, a type of falcon (Lincer 1975). An advantage of the study is that the laboratory J

relationship between DDE and eggshell thinning was validated by investigations of the

relationship in wild populations as well (see also Peakall 1993). Although kestrels do not fish,

feeding instead on birds, mammals and invertebrates (Johnsgard 1990), they are an appropriate

surrogate for herons in that both are predaceous birds(i.e., feed on animals). Eggshell thinning

of 15% or more is considered the threshold for adverse effects, despite indications in other

studies that other adverse effects may occur at lower exposures not associated with eggshell

thinning, because this level of thinning has been associated with declines of wild populations in

j field studies, and, as such, serves to integrate the overall impact of the potentially diverse

mechanisms by which DDTr may affect avian reproduction. In other words, use of the eggshell

thinning benchmark does not assume that the adverse effects are solely due to the thinning itself.

Statistically discernible eggshell thinning of 15% compared with controls occurred at

dietary levels (food concentrations) of 3 ppm DDE (wet weight basis), but not at 0.3 ppm (the

study design also included 6 and I0 ppm concentrations) (Lincer 1975). The lowest observed

adverse effect level (LOAEL) therefore corresponds to the dose associated with DDE dietary

levels of 3 ppm, and the no observed adverse effect level (NOAEL) is the dose associated with L

0.3 ppm. Dose to birds was not calculated in the original paper (i.e., the amount of DDE

consumed per unit body weight per day of the birds ingesting DDE).

The dietajr levels are converted to doses through two procedures. 1) The dietary

I ccncentrations (expressed as mg DDElkg food) are multiplied by a literature value for adult male

kestrel food ingestion rate of 0.3 1 kg food/kg,,-d ww (female rates are not given) (USEPA

1993a), where BW is body weight and ww is wet weight. The LOAEL and NOAEL are 0.93 and

0.09 mg DDE/kg,,-d. respectively. 2) The food ingestion rate for the study is estimated by L

dividing the average size of the DDE-dosed cockerels (30 g) fed daily to the kestrels, by a

literature value for adult layinglincubating female kestrel body weight of 124 g (USEPA 1993a).

The calculated food ingestion rate (0.24 kg food/kg,,-d) is multiplied by dietary levels as before.

The LOAEL and NOAEL are 0.7 and 0.07 mg DDE/kg,,-d, respectively. The lower of the two

approaches are the final values.

Kestrel DDE Toxicity Reference Values (TRV):

LOAEL - 0.7 mg DDE/kg,,-d

-

NOAEL - 0.07 mg DDE/kgBw-d.

These values are lower than the LOAEL and NOAEL of 1.1 and 0.1 1 rng DDElkgBwd,

respectively, calculated as part of the Great Lakes Water Quality Initiative from the same study

(USEPA 1995). The difference is due to the uncertainty regarding the additional amount of food

consumed ad libitum (as desired) each day beyond the initial 30-g cockerel (Lincer 1975). For

the present risk assessment, a conservative assumption is made that no additional food was

consumed. This may result in low LOAEL and NOAEL values, however, equivalent LOAELs

(0.6 mg DDE/kgBw-d) were derived by the Great Lakes Initiative from studies of mallard, Anus

plutyrhynchos, and black duck, Anus rubripes, reproduction (USEPA 1995). This supports the

reasonableness of the conservative kestrel LOAEL. The duck studies are not used in this risk

assessment because ducks primarily feed on plants, unlike herons and kestrels that feed almost

entirely on animals. An order-of-magnitude lower value (0.027 mg DDTr/kgBw-d) was proposed

based on reproductive effects in brown pelicans, Pelecunus occidentulis (Anderson, et al. 1975;

IJSEPA 1995), but brown pelicans, the bird species most sensitive to DDE of those investigated,

do not occur in Michigan. In one field study, the slopes of DDE vs. eggshell thinning were

parallel for brown pelican and great blue heron (King et al. 1978), which indicates the two

species would respond similarly to changes in DDTr concentrations in the fish in their diet.

An interspecific conversion factor of 1 is used to extrapolate the results to herons,

because falcons are among the more sensitive species for DDE-induced eggshell thinning (Keith

and Gruchy 1972).

A study on the reproductive effects of DDT in a predaceous bird was not located, but one

was performed with mallards. Dietary DDT concentration of 25 ppm dly weight (dw),

'\ I

equivalent to about 8 ppm ww, resulted in eggshell thinning, increased eggshell cracking, and

reduced duckling survival. No adverse effects were observed at a dietary DDT concentration of

10 ppm dw (about 3 ppm ww) (Heath, et al. 1969). The LOAEL and NOAEL doses were

calculated to be 1.5 and 0.6 mg DDTikg,,-d, respectively, assuming a mallard food ingestion

rate of 0.0582 kg food dw/kg,,-d and a dry weight to wet weight conversion factor of 5 (USEPA

1995). These values are adopted for use in this risk assessment.

. -~

Mallard DDT Toxicity Reference Values (TRVs):

LOAEL - 1.5 mg DDT/kg,,-d

NOAEL - 0.6 mg DDT/kg,,-d.

DDD dietary exposure as high as 40 ppm dw (about 13 pprn ww) did not cause eggshell

thinning in mallards (Heath, et al. 1969). DDD exposure was associated with impairment of

b reproductive success in the same study, but with less effect than DDE. DDD will not be

separately evaluated for risk to fish-eating birds because the potential effects are poorly

understood.

DDT is an insecticide and, as such, is highly toxic to benthic invertebrates, both to insect

larvae and to other invertebrates. DDD is more toxic to benthic invertebrates than DDT, and was

formerly recommended for control of chironomid (midge) larvae in ponds (Edwards, et al. 1964).

Chironomids are often the dominant insects in lentic (standing water) habitats (Thorp and Covich

1991), and therefore are an important component of the food base that supports fish populations

in these habitats. Sediment contamination with DDTr has been associated with adverse effects

on benthos (benthic community) at other sites (Swartz, et al. 1994; Hoke, et al. 1994 and 1997).

Adverse benthic impacts may result in adverse effects on fish productivity due to reductions in

benthos productivity andlor diversity.

Several sources of sediment benchmark values were consulted. Screening values include

lowest effect level (LEL) (Persaud, et al. 1993), threshold effect level (TEL) (Smith, et al. 1996),

and effects range low (ERL) (Long and Morgan 1990; Long, et al. 1995). Each is derived

differently. but all represent levels below which adverse benthic effects are considered unlikely,

and may be used to screen out chemicals from further consideration. The range of values are as

follows:

An indication of the potential for widespread benthic impacts is obtained by comparison

with the severe effect level (SEL), defined as the sediment concentration that could potentially

(ppm dw, whole sediment)

DDD

DDE

DDT

DDTr

0.002-0.008

0.002-0.005

0.001-0.080

0.003-0.070

') impact the majority of freshwater benthic organisms (Persaud, et al. 1993). The values are given

on a total organic carbon (T0C)-normalized basis. They are converted to a whole sediment basis

by multiplying by the mean TOC for surficial(0-6 inch depth) sediment samples as determined

by the 7/97 survey of the St. Louis Impoundment: 2.77% for the upper basin, 2.90% for the

middle basin, and 3.87% for the lower basin.

Table 2.4-2. Severe Effect Levels (SEL) for Sediments.

I Chemical I S E L ~ I upper I Middle I Lower Basin I Basin

- pp-DDD

pp-DDE

The results of comparisons with sediment benchmarks cannot be taken as proof of

I Basin

DDTr

L adverse impacts in the absence of site-specific studies. Since benthic studies have not been

'b

( ~ g / g TOC)

6

.I9

performed at the Site, another set of benchmarks are presented below to indicate the likelihood of

a) Organic carbon-normalized values (Persaud, et al. 1993). b) These values are the SELs converted to a whole sediment basis.

12

potential impacts on benthos that may be expected to result in pronounced changes in benthic

(ppm dw, whole sediment)

community parameters. One is the threshold level of sediment DDTr associated with reductions

0.17

0.53

0.33

in the abundance of amphipods (another important group of benthic invertebrates) in the field

(Swartz, et al. 1994). This study was performed in a marine ecosystem, but the threshold is

0.17

0.55

0.35

consistent with similar studies of freshwater systems (Hoke, et al. 1997). Another comparison is

0.23

0.74

0.46

with the 10-day median lethal concentration (LC,,) of DDTr-contaminated freshwater sediments

for Chironomus tenlans, a midge species (Hoke, et al. 1997). The organic carbon-normalized

values are converted to a whole sediment basis as before.

-- -

Table 2.4-3. Benthic Community Threshold and Median Lethal Concentration for I DDTr.

1 b g / g TOC) I (ppm dw, whole sediment) 1 I

Endpoint

I Value '

Basin

Amphipod abundance

b) These values are the threshold and LC,, converted to a whole sediment basis.

LC,,, C. tentans 1 2500 - 3000 ( 69 - 83 1 73 - 87

Again, comparisons with these benchmarks cannot be considered proof of adverse

Upper

1 b

> 100

97 - 116

impacts at the site, but nlay be used as part of a weight-of-evidence approach to evaluate the

likelihood and possible magnitude of potential effects at the Site.

Basin

a) Organic carbon-normalized values.

The dose to heron is calculated by assuming an adult female heron food ingestion rate of

0.16 kg/kg,,-d and a dietary composition of 94% fish (USEPA 1993a). The dose equation and

the units (all wet weight) are:

Dose = Food ingestion rate x Fraction of fish in diet x Contaminant level in fish

(mg DDE/kg,,-d) = (kg food/kg,,-d) (unitless) (mg DDEWg fish whole body).

It is assumed that 100% of the foraging occurs in the lower, middle and upper basins of

62

Middle Basin

> 2.77

Lower

> 2.90 > 3.87

) the S t Louis Impoundment. This is probably conservative for heron, but is realistic for

kingfishers. Belted kingfishers defend breeding territories of I to 2 km of shoreline along

streams, and lesser lengths along lakes (USEPA 1993a). The shoreline along the lower, middle

and upper basins is about 2 km, indicating that it could serve as a single (or even double)

kingfisher breeding territory.

Ten carp, collected from the St. Louis Impoundment on 10/17/97, were analyzed for

DDTr on a whole fish basis, as was one smallmouth bass. Whole fish data are necessary for

ecological risk assessment because wild predators eat entire fish. The range and mean .-

contaminant levels in carp, and the calculated dose to heron are as follows:

The contaminant levels in a single smallmouth bass taken from the St. Louis

Impoundment, 10117197, are 26.03 pp-DDD, 5.27 pp-DDE, 2.58 pp-DDT, and 48.66 DDTr, in

mglkg whole fish, ww. These are remarkably similar to the whole carp mean contaminant levels

Table 2.4-4. Contaminant Levels in Whole Carp, St. Louis Impoundment, 1011 7/97, and Dose Estimates to Heron.

Chemical

pp-DDD

pp-DDE

pp-DDT

DDTr

Estimated Dose to Heron

(mglkg~w-d)

3.39

2.04

0.23

7.47

Carp Contaminant Levels

Range Mean

(mglkg whole fish, ww)

5.95-87.92

4.74-29.65

0.22-4.34

14.70-161.30

22.55

13.57

1.56

49.69

Only surficial(0-6 inch depth) sediment samples are used to evaluate exposure to benthic

organisms. The percentage surface sediment samples with positive detections (out of 30 total

sample locations), and the range of concentrations are as follows:

Table 2.4-5. Range of Surficial Sediment Sample Results, St. Louis Impoundment, July 1997.

Chemical

QD-DDE

Table 2.4-6. Mean Surficial Sediment Sample Results for DDTr, St. Louis Impoundment, July 1997.

Proportion of Total Samples "

op+pp-DDT

DDTr '

(%)

17

/upper 10.81 1.67 12.14

Middle 34.16 41.19 69.46

Lower 7.1 3.71 7.16 a) Number o f sam~les with ~osit ive detections.

Surficial Sediment Sample Results

a) Number o f samples with positive detections + total number o f samples across all basins. b) Not detected. c) Sum o f positive detections for op- and pp- DDE, DDD and DDT.

43

70

Basin I Mean Positive Detections Only , a I

b) 95 percent upper confidence limit, a statistical estimate o f the highest mean (average) value if sampling was repeated many times. Non-detection samples are included at one-half the detection limit. c) Total number o f samples (both positive detections and non-detections).

(ppm dw, whole sediments)

F~,"""ions Included

195UCL IN'

Lower Basin Upper Basin

ND - 0.77

ND - 0.8

Middle Basin

ND ND ND- 1.0

ND - 169

0.97 - 169

ND

ND- 11

The risk to fish-eating birds is evaluated by the hazard quotient method. Hazard

quotients (HQ) are calculated by dividing the estimated dose to heron (Section 2.4.4.1) by the

LOAEL or NOAEL (Section 2.4.3.1), and rounding to one significant digit. HQ greater than 1 is

evidence of risk, and HQ less than 1 is below levels of concern (i.e., risk is unlikely).

The calculated dose of DDE to heron is greater than the DDE LOAEL and NOAEL. The

HQs are 3 and 30 for the LOAEL and NOAEL, respectively (Table 2.4-7). This may be

interpreted in two .ways: 1) The estimated dose to heron feeding exclusively in the St. Louis

I Impoundment is 3 times higher than the lowest dose shown to adversely affect bird reproduction

(or 30 times higher than the highest dose shown to have no adverse effects); or 2) adverse

reproductive effects would be expected in heron that obtain one-third or more of their diet from

the St. Louis Impoundment (or no more than 3% of the diet to be confident that adverse effects

L, are unlikely to occur).

The calculated dose of DDT to heron is less than the DDT LOAEL and NOAEL. The

HQs are 0.2 and 0.4 for the LOAEL and NOAEL, respectively (Table 2.4-7). The DDT

exposures considered alone are below levels of concern for bird reproduction. This is not

unexpected since DDT is metabolized to DDE in living organisms

a) Table 2.44. b) Lowest Observed Adverse Effect Level. c) No Observed Adverse Effect Level. d) Section 2.4.3.1. e) Hazard Quotient = Dose + NOAEL or LOAEL, rounded to one significant digit f) Not available

It should be noted that the highest dose to heron is for DDD, but, because its effects on

bird reproduction have been poorly studied, its risk to heron cannot be estimated (Table 2.4-7).

The dose equation for heron (Section 2.4.4.1) can be run "backwards" to calculate the fish

tissue DDE levels that would be considered acceptable for fish-eating birds. The rearranged

equation and its units are:

Acceptable contaminant level in fish =

LOAEL or NOAEL - (Food ingestion rate x Fraction of fish in diet)

(mg DDE!kg fish whole body) = (mg DDE/kg,,-d) - (kg food/kg,,-d) (unitless).

The back-calculated fish tissue level for the DDE LOAEL (0.7 mg DDEIkg,,-d) is 4.65

nlg DDElkg fish whole body, ww, and for the DDE NOAEL (0.07 mg DDE/kg,,-d) is 0.47 mg

DDE/kg fish whole body, ww. This means that the estimated threshold for adverse reproductive

effects in fish-eating birds is somewhere between 0.5 and 5 mg DDEkg whole-body fish

concentrations. These levels are met or exceeded by all ten carp and the one smallmouth bass

66

) collected from the S t Louis Impoundment for whole-body analysis (Table 2.4-4),

The final step is to calculate preliminary remedial goals (PRG) for sediments that would

be protective for reproduction in fish-eating birds. This is done by back-calculating sediment

DDT concentrations from the protective whole-body fish DDE concentrations derived in the

previous paragraph. Note that the back-calculation is not to sediment DDE, even though it starts

with fish DDE levels. This is done because the DDE in fish is mainly the result of metabolic

conversion of DDT to DDE by fish and their prey (the relative proportions of DDE and DDT are

reversed in sediments and fish - DDE is low in sediments but high in fish, and DDT is high in 'L

sediments but low in fish - the reversed patterns are due to conversion of DDT to DDE).

The relation between sediment and fish concentrations of chemicals like DDT is

described as the biota sediment accumulation factor (BSAF). BSAF is equal to the lipid (fat).

normalized fish concentration divided by the total organic carbon (T0C)-normalized

concentration in sediment. Lipid-normalized means that the fish concentration is divided by the

fish lipid fraction, and TOC-normalized means the sediment concentration is divided by the

sediment TOC fraction. Lipid- and TOC-normalization is done because DDTr is almost entirely L

absorbed by organic carbon in sediments and by lipids in living organisms. The equation for

BSAF is:

BSAF = (Fish conc. - Fish lipid) +(Sediment conc. + Sediment TOC).

It is rearranged to back-calculate a sediment concentration from a given fish concentrations as

follows:

Sediment conc. = (Sediment TOC x Fish conc.) - (Fish lipid x BSAF).

The mean sediment TOC in the St. Louis Impoundment (7/97), is 3.29% (for all sediment

sample depths), the mean whole-body carp lipid content (10117197) is 6.17%, and the mean

BSAF is 0.207 for whole-body carp. Substituting these values in the equation above gives the

following equation:

PRG = (0.0329 x Fish conc.) + (0.0617 x 0.207).

This simplifies to:

PRG = 2.576 x Fish concentration on a whole-fish basis, ww.

Substituting the whole-body fish level (4.65 mg DDEkg fish) that corresponds to the

LOAEL, the LOAEL-based PRG is 12 mg DDTkg sediment (ppm). The NOAEL fish level

(0.47 mg DDEkg fish) corresponds to a sediment PRG of 1.2 pprn.

.4 more conservative approach is to calculate 95 percent upper confidence limits (95UCL)

instead of means. 95UCL is a statistical method for calculating an upper estimate of what the

largest mean value may be if sampling could be repeated many times. The 95UCL sediment

TOC in the St. Louis Impoundment (7/97), is 4.25%, the 95UCL whole-body carp lipid content

(10117197) is 7.94%, and the 95UCL BSAF is 0.314 for whole-body carp. Substituting these

values as before gives the following PRGs: 7.9 ppm (LOAEL) and 0.8 ppm (NOAEL).

The PRG for sediments is therefore around 1 ppm DDT to be fully protective of

reproduction in fish-eating birds. Adverse reproductive effects may be expected when mean

sediment levels exceed 8 to 12 ppm DDT. These levels are based solely on the adverse effects

associated with DDE, and do not consider the potential additive effects associated with DDD or

with DDT that is not metabolized to DDE. The PRG for all forms of DDT combined would be

lower than the PRGs calculated here by an uncertain amount.

Potential adverse effects on benthic organisms cannot be ruled out because all of the

positive detections for sediment DDD, DDE, and DDT in the middle and upper basins exceed the

screening values. The detections for DDD exceed the screening values in the lower basin (Table

2.4-8).

The severe effect level (SEL) sediment benchmarks are exceeded for all positive

detections of DDD and DDTr in all basins (Table 2.4-8), representing two-thirds of the total

number of surface sediment samples. In the upper and middle basins, 4 of 5 positive detections

of pp-DDE and 5 of 13 positive detections of op + pp-DDT exceed the SELs. This indicates that

adverse benthic effects are likely at the Site. Note that the mean sediment DDTr concentrations I

also exceed the DDTr SEL (compare Table 2.4-6 and 2.4-8).

Nearly half of the positive detections for DDTr exceed the threshold benchmark for

amphipod abundance (Table 3.4-8), which includes more than 40% of the total number of surface

sediment samples (13 of 30). Three of the surface sediment samples from the middle basin \

exceed the median lethal concentration to Chironomus tenfans (Table 2.4-8). This provides

further indications that the surficial DDTr contamination at the Site is likely to result in

pronounced adverse effects on the benthic community.

a) Surficial (0-6 inch) sediment samples, July 1997. b) Rang6 of sediment.screening values including lowest effect level (LEL) (Persaud, et al. 1993), threshold effect level (TEL) (Smith, et al. 1996), and effects range low (ERL) (Long and Morgan 1990; Long, et al. 1995). They represent levels below which adverse effects on benthic organisms are considered unlikely. c) Severe effect levels (SEL) are the sediment concentrations, adjusted for mean surface sediment total organic carbon in each of the basins, that could adversely affect the majority of benthic organisms (Persaud, et al. 1993). The range of values for the three basins are given (Table 2.4-2). d) The amphipod abundance benchmark is the level of sediment DDTr associated with declines in amphiphod abundance in field studies at a different site (Swarh, et al. 1994), adjusted for mean surface sediment total organic carbon. The range of values for the three basins are given (Table 2.4-3). e) The 10-day median lethal concentration (LC,) of DDTr-contaminated sediments for Chironornus tentans, a freshwater midge, as determined at a different site (Hoke, et al. 1997), adjusted for mean surface sediment total organic carbon. The range of values for the three basins are given (Table 2.4-3). f) Not detected. g) DDTr represents the sum of DDD, DDE and DDT.

The projected severe impacts o f DDTr-contaminated sediments on benthic invertebrates

are contim~ed by the results o f a benthic survey performed in 1992. Only 2 individual benthic

invertebrates (a tubificid worm and a caddisfly case) were collected out o f 27 benthic grab

samples, a shockingly low outcome (Bohr 1992). Similar results were found in earlier surveys as

well (Michigan Water Resources Commission 1970 cited i n Bohr 1992). Based on these

surveys, there is essentially no benthic community in the Pine River above the St. Louis dam.

') The 1992 survey also shows that DDTr is not solely responsible for the elimination of the

benthic community from the Pine River above the St. Louis dam. Two of the benthos transects

were located upstream of the DDTr-contaminated zone (one between the Washington Ave. and

State St. bridges, the other between the State St. and Rt. 27 bridges). The upstream transect grab

samples "contained a large amount of sludge that was obviously the result of effluent released

from the oil refining plant at Alma" (Bohr 1992). The presence and impact of oily wastes in the

Alma-St. Louis stretch of the Pine River mean that restoration of benthic community functions is

unlikely following remediation of DDTr-contaminated sediments. The primary ecological

justification for remediating the sediments is therefore to protect fish-eating birds.

All risk assessments require that judgements be made on the choice of exposure pathways

and species to evaluate, the studies to utilize, and the additional parameter values and

'L/ extrapolations needed to calculate the levels of risk. The alternative would require extensive

studies that, to ensure a high degree of certainty, would be open-ended for cost, time and

manpower. The main uncertainties of this ERA are described below under three categories of

how they might affect the risk estimate: overestimate, underestimate, and either.

The main assumption that may overestimate risk (i.e., the ERA indicates greater risk than

7 1

what actually occurs at the site) is that 100% of the fish are caught from the St. Louis

Impoundment. This is potentially more significant fbr heron than for kingfishers, which defend

relatively small foraging territories. This uncertainty is addressed for heron by inverting the

hazard quotient to estimate the fraction of the diet that would be have to be taken from the St,

Louis Impoundment to result in adverse effects.

Another uncertainty concerns the species and sizes of the fish caught by fish-eating birds

at the St. Louis Impoundment. The whole fish data are for carp ranging from 17 to 20 inches in

length. This is larger than the usual fish size taken by great blue heron: 2-10 inches to a

maximum of 16 inches (USEPA 1993b), which may result in an overestimate of exposure if

older (longer) fish accumulate more DDTr than younger (smaller) fish. A related question

concerns the mix of prey species consumed by fish-eating birds at the Site. Different species of

fish may accumulate different levels of DDTr than carp. Carp are known to accumulate high

levels of lipophilic contaminants because they have high fat content and feed mostly on the

bottom. Other species may have lower contaminant levels, although the one whole-fish

sniallmouth bass at the Site had similar levels of DDTr as the carp.

Another possible overestimation of risk is the assumption that heron andlor kingfisher are

as susceptible to DDE-induced eggshell thinning as kestrels. There is some, but not conclusive.

evidence that this is not the case.

The toxicity reference value (TRV) derived from the kestrel study (Lincer 1975) may be

low, which would overestimate risk, because of the conservative dietary assumption. However,

the TRVs used for this risk assessment are equivalent to the TRVs calculated from mallard and

black duck studies, which increases confidence in their use. Also, the kestrel TRVs are an order-

72

' of-magnitude greater than the TRV calculated for brown pelicans (i.e.. risk for brown pelican

would be 10 times greater than for kestrels), which indicates that the conservative kestrel TRV

by no means results in an unreasonably high risk estimate.

Several factors might result in underestimation of risk (i.e., the ERA indicates less risk

- than what actually occurs at the site). A major one is that the risks to fish-eating birds are

separately estimated for the effects of DDE alone and DDT alone. There is no consideration of

the possible combined effects of all the DDTr. The inability to assess the risk of DDD to fish-

eating birds may be particularly important in this regard since DDD exposure is higher than for 1

DDE or DDT. Similarly, the back-calculations of sediment preliminary remedial goals are based

solely on the effects of DDE.

'The focus on egg-shell thinning as the adverse effect of concern might result in

L underestimation of risk if other effects (e.g., embryo mortality, hormonalibehavioral effects)

occur at substantially lower levels of exposure

The estimated risk at the site would have been about 10 times greater if the brown pelican

study were used in place of the kestrel study. Risk might also be underestimated by the use of an

interspecies conversion factor of 1. Commonly, conversion factors as high as 10 are used to

ensure that the results of the risk assessment will protect species that have not been studied, but

might be more susceptible than the ones that have been studied

Some exposure pathways and potential receptors have not been considered. One is

73

exposure to insectivores (insect-feeders) via emergent insects from the~St; Louis Impoundment.

Many of the benthic invertebrates are insect larvae that can cany DDTr contamination witbthem

when they emerge from the water as flying aduits. This can result in significant exposure to

bi rds (e.g., swallows, swifts, waxwings), bats, and frogs. However,since the benthic community

is severely impacted by oily wastes between Alma and St. Louis, this exposure pathway~has been

virtually eliminated.

The direct effects of DDTr on fish or amphibians are not assessed. It is assumed for this

risk assessment-that the effect on fish-eating birds is a more sensitive endpoint than the effects on W

~

fish and amphibians. If this assumpiion is invalid, risks to the aquatic ecosystem may be

underestimated.

None of the kestrel or duck laboratory studies reported the food ingestion rates of the test

animals, information necessary to convert the reported dietary concentrations to doses. Inboth

cases. ingestion rates were derived from literature values. The uncertainty over the actual

ingestion rates during the laboratory studies carries over directly touncertainty over the

calculated do&. It is not known whether the ingestion rate estimates are high or lowfor the duck

studies.

Similarly, there is uncertainty over value of the ingesiion rate for great blue heron in the

field. Again, i: is not known whether this results in over- or underestimation ofrisk.

The comparisons of the sediiiient DDTr concentrations with screening values and the

74

) results of studies at other sites are uncertain in two respects The toxicity of sediment

contaminants to benthic invertebrates is affected by several factors besides the concentration of

the contaminant. Organic carbon-normalization is an attempt to control for one of the known

modifying factors, but there are other factors that are not controlled. This is why site-specific

sediment toxicity tests are required for setting remedial goals for protecting benthic invertebrates.

Secondly, there is additional uncertainty in applying the results of laboratory toxicity tests to the

field where conditions and species interactions are different from those in the lab. However, the

.- benthic surveys demonstrate that the benthic community is severely impacted.

The results of the ecological risk assessment shew that fish-eating b~rds. as represented

by great blue heron, that consume fish from the St. Louis Impoundment are at risk for

reproductive impairment related to eggshell thinning and other adverse effects caused by DDE.

L The calculated dose of DDE to heron is 3 times greater than the DDE lowest observed adverse

effect level (LOAEL), and 30 times greater than the no observed adverse effect (NOAEL).

Adverse reproductive effects would therefore be expected in heron that obtain one-third or more

of their diet from the St. Louis Impoundment. Adverse effects are unlikely to occur in fish-

eating birds that obtain no more than 3% of their diet from the St. Louis Impoundment.

The preliminary remedial goal (PRG) for sediments is 1 ppm DDT to be fully protective

of reproduction in fish-eating birds. This sediment concentration should result in 0.5 mg

DDEIkg whole fish, the dietary concentration that corresponds to the NOAEL. Adverse

75

reproductive effects may be expected when mean sediment levels exceed 8 to 12 ppm DDT,

which should result in about 5 mg DDEIkg whole fish (LOAEL). These levels are based solely

on the adverse effects associated with DDE, and do not consider the potential additive effects

associated with DDD or with DDT that is not metabolized to DDE.

Concentrations of DDTr in St. Louis Impoundment sediments exceed sediment screening

values for potential adverse effects on benthic invertebrates. Two-thirds of the surface sediment

samples also exceed the severe effect levels (SEL) that indicate a potential for adverse effects on

the majority of benthic organisms. Forty percent of the surface sediment samples exceed the

threshold for adverse effects on benthic populations as determined at another site. Three samples

from the middle basin exceed the median lethal concentration (LC,,) determined in sediment

toxicity tests at another site. Benthic surveys of the Pine River demonstrate that the benthic

community has been nearly eliminated between Alma and St. Louis, and also indicate that oil

refinery wastes are impacting the benthos in addition to the effects due to DDTr. Although the

relative contributions of DDTr and oily wastes to the stresses on the benthic community cannot

be precisely determined, the combined results of the survey and screening of DDTr data with

sediment benchmarks support the conclusion for fish-eating birds that the site represents a

significant ecological risk.

Anderson, D. and J. Hickey. 1972. Eggshell changes in certain North American birds. in Proceedings of the XVth International Ornithological Congress, The Hague, The Netherlands, 30

76

' Aug - 5 Sept 1970. K. Voous (ed.). E.J. Brill, Leiden. pp. 515-540.

Anderson, D., J. Jehl, R. Risebrough, L. Woods, L. Deweese, and W. Edgecombe. 1975. Brown pelicans: Improved reproduction off the southern California coast. Sci 190: 806-808.

Blus, L., C. Gish, A. Belisle and R. Prouty. 1972. Logarithmic relationship of DDE residues to eggshell thinning. Nature 235: 376-377.

Bohr, J. 1992. Aquatic Resources Inventory, St. Louis Municipal Dam Impoundment, Pine River, Gratiot County, Michigan, September 18-20, 1992, prepared for The City of St. Louis, Michigan.

Brewer, R., G. McPeek, and R. Adams, Jr. 1991. The Atlas of Breeding Birds of Michigan. Michigan State University Press, East Lansing. 594 p.

Edwards, J. 1992. DDT effects on bird abundance and reproduction. in Rational Readings on Environmental Concerns. J. Lehr (ed.). Van Nostrand Reinhold, New York. pp. 195-216.

Edwards, R., H. Egan, M. Learner and P. Maris. 1964. The control of chironomid larvae in ponds, using TDE (DDD). J Appl Ecol 1: 97-1 17.

Fox, G. 1974. Changes in egg shell quality of belted kingfishers nesting in Ontario. Can Field- Naturalist 88: 358-359.

Fox, G. 1976. Eggshell quality: Its ecological and physiological significance in a DDE- contaminated common tern population. Wilson Bull 88: 459-477.

Haegele, M. and R. Hudson. 1973. DDE effects on reproduction of ring doves. Environ Pollut 4:

b' 53-57.

Haegele, M. and R. Hudson. 1974. Eggshell t h i ~ i n s and residues in mallards one year after DDE exposure. Arch Environ Contam Toxicol 2: 356-363.

Haegele, M. and R. Tucker. 1974. Effects of 15 common environmental pollutants on eggshell thickness in mallards and Coturnix. Bull Environ Contam Toxicol 1 1 : 98-102.

Heinz, G., E. Hill and J. Contrera. 1980. Dopamine and norepinephrine depletion in ring doves fed DDE, dieldrin, and Arochlor 1254. Toxicol Appl Pharmacol 53: 75-82.

Henny, C., L. Blus, A. Krynitsky, and C. Bunck. 1984. Current impact of DDE on black- crowned night-herons in the intermountain west. J Wild1 Manage 48: 1-13.

Hoke, R., G. Ankley, A. Cotter, T. Goldstein, P. Kosian, G. Phipps, and R. VanderMeiden. 1994. Evaluation of equilibrium partitioning theory for predicting acute toxicity of field-collected sediments contaminated with DDT, DDE and DDD to the amphipod Hyulella azreca. Environ Toxicol Chem 13: 157-166.

Hoke, R., G. Ankley, P. Kosian, A. Cotter, R. VanderMeiden, M. Balcer, G. Phipps, C. West, and J. Cox. 1997. Equilibrium partitioning as the basis for an integrated laboratory and field assessment of the impacts of DDT, DDE and DDD in sediments. Ecotoxicol6: 101-125.

Jefferies, D. and M. French. 1971. Hyper- and hypothyroidism in pigeons fed DDT: an explanation for the "eggshell phenomenon". Environ Pollut I: 235-242.

Jefferies, D. and M. French. 1972. Changes induced in the pigeon thyroid by p,p'-DDE and dieldrin. J Wild1 Manage 36: 24-30.

Johnsgard, P. 1990. Hawks, Eagles, & Falcons of North America, Biology and Natural History. Smithsonian Instution Press, Washington. 403 p.

Keith, J. and I. Gmchy. 1972. Residue levels of chemical pollutants in North American birdlife. in Proceedings of the XVth International Ornithological Congress, The Hague, The Netherlands, 30 Aug - 5 Sept 1970. K. Voous (ed.). E.J. Brill, Leiden. pp. 437-454.

King, K., E. Flickinger, H. Hildebrand. 1978. Shell thinning and pesticide residues in Texas aquatic bird eggs, 1970. Pesticide Monitor J 12: 16-21.

Liincer, .l. !975. DDE-induced eggshell-thinning in the American kestrel: a comparison of the fie!d situation and laboratory results. J Appl Ecol 12: 781-793.

Long, E. and L. Morgan. 1990. The Potential for Biological Effects of Sediment-Sorbed Contaminants Tested in the National Status and Trends Program. NOAA Technical Memorandum NOS OMA 52. National Oceanic and Atmospheric Administration, Seattle.

Long, E., D. XlacDonald, S. Smith and F. Calder. 1995. Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuarine sediments. Environ Managem 19: 81-97.

Lundholm, E. 1987. Thinning of eggshells of birds by DDE, mode of action on the eggshell gland. Comp Biochem Physiol88C: 1-22.

Michigan Water Resources Commission. 1970. Pine River Water Quality Study, 1967-1970 Michigan Dept. Natural Resources, Bureau of Water Management.

) Peakall. D 1993 DDE-induced eggshell thinning: an environmental detective story. Environ Rev I: 13-20.

Persaud, D., J. Jaagumagi and A. Hayton. 1993. Guidelines for the Protection and Management of Aquatic Sediment Quality in Ontario. Ministry of Environment and Energy, Toronto. PlBS 1962.24 p.

Porter, R. and S. Wiemeyer. 1969. Dieldrin and DDT: effects on sparrow hawk eggshells and reproduction. Sci 165: 199-200.

Prestt, I. and D. Ratcliffe. 1972. Effects of organochlorine insecticides on European birdlife. in Proceedings of the XVth International Ornithological Congress, The Hague, The Netherlands, 30 Aug - 5 Sept 1970. K. Voous (ed.). E.J. Brill, Leiden. pp. 486-513.

- Scott, M. 1977. Effects of PCBs, DDT and mercury compounds in chickens and Japanese quail. Fed Proceed 36: 1888-1893.

Smith, S., D. MacDonald, K. Keenleyside, C. Ingersoll, and L. Field. 1996. A preliminary evaluation of sediment quality assessment values for freshwater ecdsystems. J Great Lakes Res 22: 624-638. .

I Swartz, R., F. Cole, J. Lamberson, S. Ferraro, D. Schults, W. DeBen, H. Lee 11, and R. Ozretich. 1994. Sediment toxicity, contamination and amphipod abundance at a DDT- and dieldrin- contaminated site in San Francisco Bay. Environ Toxicol Chem 13: 949-962.

Thorp, J. and A. Covich (eds.). 1991. Ecology and Classification of North American Freshwater Invertebrates. Academic Press, New York. 91 1 p.

L USEPA. 1993a. Wildlife Exposure Factors Handbook. vol. 1. Office of Research and Development. EPN600/R-93/187a.

USEPA. 1993b. Wildlife Exposure Factors Handbook. vol. 11. Office of Research and Development. EPN600/R-931187b.

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Vermeer, K. and L. Reynolds. 1970. Organochlorine residues in aquatic birds in the Canadian Prairie Provinces. Can Field-Naturalist 84: 117-129.

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zi Goals for DDT h e P~ne RIVU

EPA utilized a volume break point analysis and risk reduction analysis to determine a

protective and cost effective cleanup goal for total DDT in the Pine River. Table 2.5-1 shows a

range of cleanup goals (1,5, 10 and 100 ppm total DDT) and compares the area, volume of

sediment rcquired to be removed, and total DDT mass that would be removed if the goal were

met. The average dredging depth is assumed to be 5 feet.

Table 2.5-2 shows the concentration of total DDT that would remain in fish tissue and

Table 2.5-1 Volume Break Point Analysis

reduction in risk if a cleanup goal of 1 or 5 ppm total DDT were met.

Conc. (ppm)

1

Area (acres)

65 '

Volume (cy)

516,650

Mass (Ib)

538,730

Table 2.5-2 Post Remedial Risk

Removing sediment with DDT at or above 5 ppm, will reduce levels of DDT in fish

Concentration in Fish I Concentration in Fish

Cleanup Goal

1 P P ~

5 PPm

tissue by over 95% from current levels of 12.5 to 0.8 ppm in Bass and 42.5 to 1.7 ppm in Carp.

A 1 ppm cleanup doubles the total volume of sediment to be removed while providing only an .-

RME Risk

Smallmouth Bass

0.5 ppm

0.8 ppm

additional 0.3 ppm reduction in fish tissue levels (12.2 to 0.5 ppm). Therefore, removing

RME Risk

sediment in the Pine River contaminated with 5 ppm DDT and higher, will obtain the maximum

Carp

I .O ppm

1.7 ppm

reduction 3f risk tb human health and the environment that is practicably achievable at the site.

-. 1 o attain a 5 ppm level in sediments approximately 260,000 cubic yards of sediments would be

Smallmouth Ba$s

I . I E-05

1.9E-05

removed from the St. Louis Impoundment.

Carp

z . ~ E - o ~

4 IE-05

SECTION 3 - IDENTIFICATION AND SCREENING OF REMEDIAL TECHNOLOGIES

u . .

This section identifies the site-specific Remedial Action Objectives (RAOs). These

RAOs pertain to "general site cleanup" or are intended to fulfill potential federal and state

Applicable or Relevant and Appropriate Requirements (ARARs) and "to be considered criteria

(TBCs).

As stated in USEPA's "Guidance for Conducting Remedial Investigations and Feasibility

Studies Under CERCLA" (USEPA, 1988a), remedial action objectives consist of media-specific

or operable-unit-specific goals for protecting human health and the environment. Further, the

guidance indicates constituents of concern. exposure route(s) and receptor(s). and preliminary

remediation goals that should be specified in the remedial action objectives. USEPA's

"Guidance on Conducting Non-Time-Critical Removal Actions Under CERCLA" (USEPA,

1993) states that objectives should be identified which clearly define the scope of the action

under consideration. If future remedial activities may be undertaken at the site, or if the site is to 'V

be remediated in a "phased" approach, the objectives should consider the scope of such future

activities. The RAOs proposed for this site, where DDT and its congeners are the primary

constituent of concern, are as follows:

Reduce DDT concentrations in fish and sediments in the SLI to levels that would

not present an unacceptable human- health or ecological risk and allow

elimination of existing fish consumption advisories;

. Prevent direct contact of sediments to humans;

82

. Prevent significant down river migration of contaminated sediments;

Achieve compliance consistent with federal and state ARARs for the Site; and

. Comply with risk-based objectives defined by the risk assessment.

The ability of a given alternative to meet most or all of the RAOs will be considered as

part of the evaluation of alternatives.

22

- The Comprehensive Environmental Response, Compensation and Liability Act of 1980

(CERCLA), as amended by the Superfund Amendments and Reauthorization Act of 1986

(S.4RA). specifies that Superfund remedial actions must comply with the requirements of federal

and state environmental laws. Such laws are termed ARARs, and may be either "Applicable", or

"Relevant and Appropriate". .4RARs are identified on a site-specific basis where it is first

determined whether a given requirement is applicable, then, if it is not applicable, whether it is

both relevant and appropriate.

- Applicable requirements are those cleanup standards, standards of control, or other

substantive environmental protection requirements, criteria, or limitations promulgated under

fedenl, state, or local law that address a specific problem or situation at a site. In contrast,

Relevant and Appropriate requirements are promulgated environmental protection standards,

requirements, criteria, or limitations which, while not applicable to a particular site problem or

situation, may be sufficiently similar to warrant their use.

In addition to ARARs, federal and state advisories and guidance documents exist which,

although not binding regulations, may be considered when remediating a CERCLA site. These

83

criteria, referred to as TBCs, are regarded as aspirational goals for potential response actions.

TBCs may be useful in determining what is protective of a site or the approach in implementing

certain actions or requirements.

The identification of site-specific ARARs is based on specific constituents at a site, the

various response actions proposed, and the general characteristics of the site. As such, ARARs

are classified into three general categories:

I. Chemical-specific ARARs, which are specific to the type(s) of constituents,

pollutants, or hazardous substances present at a site; W

2. Action-specific ARARs, which are specific to the activities being considered and

are usually technology or activity based; andlor

3. Location-specific ARARs, which represent restrictions placed on actions based on

the geographic location.

A list of potential federal and state ARARs and TBCs is presented in Tabie 3.2 It should

be noted that the list of ARARsiTBCs was developed based on appropriate guidance documents

(CERCLA Compliance With Other Laws Manuals: Interim Final, 1988b, and Part 11, 1989), ' w'

listings provided by the USEPA and preliminary Michigan ARARs provided by MDEQ. Table

3.2 identifies potential ARARsITBCs and provides a regulatory citation and brief description for

each. The table also identifies whether the regulation applies to any portion of the anticipated

scope of work and if so, whether it is a potential ARAR or TBC.

Similar to the RAOs identified previously, site conditions or other constraints may inhibit

the ability to satisfy all ARARs. However, the ability to achieve ARARs will be a consideration

during both the development and evaluation of response alternatives. In addition, once a

84

.- - TABLE 3.2

Chemical, Action. Location Specitic ARARS

Chemical Specitic ARARP Regulation 1 Citation I Description I Rationale

I I treatment substances. I discharge water. CIWI Water Act 40 CFR Pan 132 I Water Oualifv Guidance for the Oreat I To be considered for assessine water 1

C l a l Water Act - Amblent Water Quality Cnteria . .

I I I ~ & e s system I quality in the St. Louis lmpoidment and 1 . ,

I designnted water use. -

I 40CFR 131

EPA 44015-861001

C l m Water Act

Clean Water Act

Criteria for protection of aquatic life and/or human health depend in^ on the

I water quality. -

I

I I I I govern if more string4t than Federal 1

Applicable for assessing water quality in the River

40 CRF 122, I25.403,230

I:cdcral Walcr Pollution Control Act Toxic Pollutant Ftlluntt Standards . . I navigable waters.

- I lnto the river. .

May be relevant and appropriate for remedral alternatives which treat and/or

CWA 402, 33 USC 1342

Watcr Qua!ity Standards

Requirements of permits for return flow, which includes additional water or

Establishes site-specific pollulant limitations and p e r l o m c e standards, which are desimed to ~rotect surface

40 CFR 129

IISDOT Placarding and klolidllng

Michigan Water Resources Commiss~on PA451.Part31 R323.1011 ff, especially R323 1057 &

R323.1082, and adnunistrative rules t

the Pine River. May be relevant and appropriate for alternatives which treat and/or discharge water

I DDD or 6 1 3 ~ . ' -

Regulates water and wastewater discharges, provisions for the non- degradation of groundwater quality.

Establishes emuent slandards for t o ~ c comuounds. Ao~lies to dischar~es to

Relevant and appropriate to protect surface water. Slate specific ARARs ulll

40 CFR 131

49 CFR 171 et. seq.

Micl~igan Environmental Response Act

for the site.

alternatives whtch will treat and/or discharge wastewater to a water of the state. Cites spec~fic requiremcmt for discharge of DDI' m wastewater. Permit requirements can be met through

May k applicable for alternatives, which would include discharw of water back

Surface water quality requirements.

I I 1 subslantive requirement docu&ents. Michlaan Air Pollution Act PA451.Part55 I Prohibits the emissions of air I Relevant and amro~riate for r e m d a l

Transportation and handling requirements for shipments of sedments containing one pound of more of DDT, DDDand DllE

PA 451, Par201 R324.20101 K

and administrative rules

m s . Applicable for transporting requirements. Would apply to any alternative which included off-srte transpacf of sediments containinn one nound or ereater of IIDT.

Regulations concerning conducting environmental reswnse actions.

Applicable for assessing the river and conductinalselectinp, remedial alt~matives

I

contaminants in quantities, which cause injurious etfects to human health, animal life, plant life of signiticant economic value, and/or property. Establishes requirements for hazxdous waste generators, transporters, and treatment/storage/disposaI facilities.

Michigan Hazardous Waste Management Act

.. . alternatives that would generate air emissions. Permit requirements wuld be met Uuough a suhsmtive requirement document. Used for determining how and in what type of disposal facility the sediments can be removed to.

PA45l,Part 111 and admmistrative rules

Regulation M~ch~gan Solld Waste Management Act

Clean Water Act

Clean Water Act

RCSO~~CL- C'onscrvation and Recovery Act

Michig;m b:nviro~nncnhl Response Act

Mlchlgan Watcr Resources Commlsalon Act

Michigan Ihdangercd Sllecies Act

Mlclugan Inland l.ahes and Steams Act

Michlgan Natural Rlvers Act

Michigan Soil Erosion and Sedimentation Control Act

Citation PA451, Part 115

and administrative rules

CWA 33 USC 144

40 CFR Part 132

40 CFR Subtitle C and D

PA451, Part 201 R324.20101 11:

R323 1082, and adm~n~stratlve rules

PA451, Part365 and administrative rules

PA451, Part 301 and administrative rules

PA451.Part305 and admi~strative rules

PA451,Part91 and administrative rules

Description Regulates the wnstruction and opaation

I of &tan landfills. solid waste transfer

material into waters of the U.S.

Water Quality Guidance for the Great Lakes Svstem

Establishes criteria for the classification: treatment. staraae and dis~osal of RCRA listed and/or characteristic wastes, and solid waste Regulations concerning conducting environmental response actions.

Regulates water and wastewater discharges, provisions for the non- degradation of groundwater quality.

Establishes rules to provide for conservation, management, enhancement, and protection of species either endangcred or threatened with extinction.

Regulates dredging or filling of luke or s w a m bottoms.

Regulates activities conducted within a natural river area.

Establishes rules prescribing soil erosion and sedimentation control plans, procedures, and measures.

Rationale

type of disposal facility the sediments can be removed to.

include capping sediments in place or

To be considered for assessing water quality in the St. Louis Impoundment and the Pine k v e r .

sedin1ents.

Applicable for assessing the river and conductinglselesting remedial allernatlves for the slte Relevant and appropnale lor rcmcdldl alternatives which &II treat andlor I ~ ~~ ~

discharge wastewater to a water of the state. Cites specific requirement tbr discharge of DDI' in wastewatc7. Permit requirements can be met through

endangered or threatened species within the am. For the site -bald eagles. u ~ m d turtles and lake cress will need to be

grotected. ' 0

Relevant and appropriate for remedial alten~atives that would dredge the river bonom. Perm11 requirements can be met though substantive requirement

remediation conducted within a natural

.. . oinosmn dnd ~ ~ m c m w t l o ~ ~ icnluol uill he n s c c r w lo nrotect the l?nc Klver from sloughing &d buildup in current I

Actiun Specific ARARs (continued)

Regulation I Citation I Description I Rationale M~cliipan Air I'ollut~un Act PA451.Pafl55 I Prohibits the emissions of air I Relevant and appropriate for remedial

and adnlinistrative N ~ C S I contamirlmits in ouantities, which cause I alternatives that urould eencrate air I injurious etrccts to human health, animal emissions. Perm11 requlreinents could h life. vlant life of sipllificant economic I met " through a suhst;uitive reauiremnent . . I value, and/or property.

- I document.

M!clt~pen Solid Waste Management Act

Used for determining how and in what t y p of disposal facility the sedimmls can

Michigan Ila/ilrdr,os Wast~. Mirnagc~nent Act

PA451,Part 115 and adm~nistrative N ~ S

I'A41i,Part I l l and adm~nistrative rules

Establishes requirements for hazilrdous w a ~ t e ycneraturs, transporters, and treat&n~stora~e/dis&sa~ facilities Regulates the construction and operation of sanitaq landfills. solid waste transfer facilities, and solrd waste processing

be removgd to. Used for ddermining how ilnd in what t y p of disposal facility !he sedimalts can be removed to

4 - blruiion Specific ARARr . f

Reeulstiun I Citation I Description I Rationale C‘Ieml Watcr Act CWA 33 USC 144 I Renulates lhc dischar~e of dredned or fill I Anolicable to remedial altemalives which

I I 1 n~aierial into waters ;the US." I include capping sed~ments in place or I . .

I I .. ~ I removing.

C l w l ~ Watcr A d

1:ndongered Specics Act

33 CI:R 320 - 330 3 lJSC 403 el scq.

Fish and Wildlifc Cwrdinalion Act

Prohibits w~authorizcd obstruction or alteration of any navigable water in the U S.; requirements of p rmi t s for incidental discharge of dredged materials afler being dredged, requirements of pern~its affecting navieable water of the

40 CFR Part 132

l6lJSC 1531 el seq 50 C r R 200,402

d~xhnrg- 01'drcdt.e and f i l l Annronrlai~~ 1%) nr<.te;l ndvl~al~le

16 lJSC 661 et seq. 33 CI:R 320 - 3311

40 CFR 122 49

.. . of thr I1 S ~ e m e d l a l actlo: may have to I

Water Quality Guidance for the Great Lakes System

Requires federal agencies lo ensure that the continued cxistence of any endangered or threatened species and their habitats will not be jeopardized by a

bo conducted m such a wa) as to ilvo~d ohstruct~on or alturat~on ol~harhor

To be considered for assessmng water quality in the St. Louis Impoundment and the Pine R~ver. Applicable to protect endangered spc ies Impoundment area may be frequented h) bald eagles.

site action. Rntectiou of endangered species and wildlife

May be releva11 and appropriate. Consultation on measurcs lo protect wildlife Recommended when on-site

I - - 1 ~ J S . I

I<lvers & Ilarhors Act

M~chigan inland l.&cs and Steams Act

federal agencies, where possible, to avoid or minimue adverse impacts of federal action upon wetlands/floodplains and

PA451, Pan3111 and administrative rules

I

st- bottoms:

40 CFR 6 302 40 Ci:R 6, ADD. A

M~chigen Natural Rivers Act Regulatcs acti\.ities conducted within a natural river area.

PA451, Part3115 and ah~nis l ra t ive rules

any work conducted in l la)d plains or wetlands

EPA Executive Orders 11988 - F l d p l a i n Managenlent. Requires

Relevant and approptiale for remedial alternatives that would dredge the river bottom. Permit requirenlmts can be met through substantive requiremet~t

Appllcahlr for thc protection of wetlands and iladplains. 1;necutivt: orders aflect

documents Relevant and appropriate to all remediation conducted wthln a natural nver area to ensure protc2tion.

. . Michigun Iannland and Open Space I'rexrvation Act

would need to be given to this act if the Cirat~ot County Landfill site were used and also when selecting truck roules

PA 451, Pan 361 and administrative rules

Restrict act~vitlcs to prevent the destruction of i'annla~d and o m spaces

Relevant and appropriate to protect farmland in the area Considerat~on

\ i response alternative has been selected, additional ARARs may be identified which will need to

be addressed, to the extent possible, during the design and implementation phases.

3.2

General response actions describe those actions that will satisfy the remedial action

objectives. General response actions may include treatment, containment, excavation, extraction,

disposal, institutional actions, or a combination of these. Like remedial action objectives,

L general response actions are medium-specific.

In order to meet the RAOs for contaminated sediments the proposed general response

actions are:

1 No Action

" Sediment Removal via Excavation or Dredging

* Disposal in On-site or Off-site Landfill

* Capping Sediment In-Situ

L

14 and Screen -es and Process Optlans

Table 3.4 evaluates the potentially applicable technology types and process options with

respect to technical implementability. "Technology types" refers to general categories of

technologies, such as chemical treatment, thermal destruction, immobiliztion, capping, or

dewatering. The term "process options" refers to specific processes within each technology type.

For example, the chemical treatment technology type would include such process options as

precipitation, ion exchange, and oxidation/reduction. During this screening step, process options

85

and entire technology types are eliminated from further consideration on the basis of technical

implementability. This is accomplished by using readily available information from the

Remedial Investigation site characterization on contaminant types and concentrations and onsite

characteristics to screen out technologies and process options that cannot be effectively

implemented at the site.

TABLE 3.4

(Shading Indicates Process Option Screen Out)

A. No Action

I B. In-Place Containment

W General Response Action/Technology Type

Fish Consumption Advisories

I. Capping

Sediment Monitoring

Process Option

Advisories indicate that a~nsumption o f fish in the area present a health risk

Periodic field sampling to track existing site conditions.

Applicable, in place since mid 1970s.

Sand cover

I C . In-Silu Treatment

Process Description

Potentially applicable; commonly implemented institutional control.

Multi-media cap

Preliminary Assessment

Sand cover placed over sediment to isolate the constituents

Potentially applicable: however without dredging to increase depth of SLI capping would significantly reduce the hydraulic capacity of the

Layers of materials (e.g, clean, sand, gravel. geotextile liner) are placed over sediment to isolate the constituents

Potentially applicable; however without dredging to increase depth of SLI capping would significantly reduce the hydraulic capacity of the SI.1.

and excavate materials (e.g.

IV. Hydroclnnc Slurry is fed tangentially into a funnel- shaped unit to facilitate centrifugal forces necessary to separate solids form liquids. Dewatered solids are collected and overflow liquid is discharged.

Potentially applicable: Technique to provide particle size separation.

Disposal o f solids (containing low Potentially applicable; however, a

permitted solid waste landfill contain elevated levels o f DDT

iL5. Evaluate Process Options

The next step is to evaluate the technology processes considered to be implementable in

greater detail before selecting one process to represent each technology type. One representative

\~. process is selected, if possible, for each technology type to simplify the subsequent development

and evaluation of alternatives without limiting flexibility during remedial design.

Process options are evaluated using the same criteria - effectiveness, implementability,

and cost - that are used to screen alternatives prior to the detailed analysis. An important

distinction to make is that at this time these criteria are applied only to technologies and the

general response actions they are intended to satisfy and not to the site as a whole. Furthermore,

the evaluation typically focuses on effectiveness factors at this stage with less effort directed at

the implementability and cost evaluation.

TABLE 3.5

Moderate capital costs, but long-term O & M

is widely available.

Lh

I In assembling alternatives, general response actions/technology types and the process

options chosen to represent the various general response actions/technology types for each

medium or operable unit are combined to form alternatives for the site as a whole. Appropriate

treatment and containment options should be developed. To assemble alternatives, general L

response actions should be combined using different technology types and different volumes of

media and/or areas of the site. Often more than one general response action is applied to each

medium. At this site there is only one medium being evaluated, sediments. The assembled

alternatives are described below:

B l t t : No Action - This alternative involves taking no additional action at the Site, but

includes fish tissue monitoring and fish advisories that are currently in place. This alternative

serves as a baseline against which other alternatives are evaluated.

Waste Removal Alternatives

lves 2Aand2B: Hydraulic Dredging, Dewatering and Water Treatment - Alternative 2A

considers hydraulic dredging of sediments with DDT concentrations in excess of the identified

action level (approx. 250,000 cu. yds.), dewateringof sediments, addition of a stabilizing agent,

water treatment and discharge to the Pine RiverISt. Louis Impoundment. The water treatment

will be designed to meet surface water discharge requirements and will probably consist of

clarification, sand filtration, carbon filters and 1 micron bag filters. Alternative 2B is identical to

Alternative 2A except that only the sediments considered to be the "hot spot" or principle threat

(approx. 50,000 cu. yds.) would be removed with dredging. Limited monitoring also would be

impiemented under this alternative.

A h m t i v e s 3A and 3B: Mechanical Dredging, Dewatering and Water Treatment - Alternative

3A considers gasketed clamshell dredging of sediments with DDT concentrations in excess of

the identified action level (approx. 250,000 cu. yds.), dewatering of sediments, addition of a

stabilizing agent, water treatment and discharge to the Pine RiverISt. Louis Impoundment. The

water treatment will be designed to meet surface water discharge requirements and will probably

consist of clarification, sand filtration, carbon filters and 1 micron bag filters. Alternative 3B is

identical to Alternative 3A except that only the sediments considered to be the "hot spot" or

92

' principle threat (approx. 50,000 cu. yds.) would be removed with dredging. Limited monitoring

also would be implemented under this alternative.

,3hn&~A: Hydraulic Modification of the Pine River, Excavation, Dewatering and Water

Treatment. Alternative 4 is similar to Alternative 3A except that temporary cofferdams will be

placed in the St. Louis Impoundment, water will be pumped from the cofferdam, the sediments

will be excavated instead of dredged, a stabilizing agent will be added and water will be treated

L prior to discharge to the Pine River. The water treatment will be designed to meet surface water

discharge requirements and will probably consist of clarification, sand filtration, carbon filters

and 1 micron bag filters.

Contaminated Sediment Disposal Optiot~s

.r\ltemative: This alternative considers disposal of sediment in a commercially operated RCRA

subtitle D landtill located in the State of Michigan.

L

Akmgi~&: This alternative considers disposal of sediment in a commercially operated RCRA

subtitle C landfill.

Containment Option

Ahmw. This alternative considers capping all the contaminated sediments in place.

Alternative 7 considers the placement of a sand cap with a stone armoring system consisting of a

93

20-inch coarse-grained sand cap and 5- to 7.5-inch diameter stone armor layer. Monitoring

would occur every 2-3 years and cap replenishment would occur every 5 years.

3 2

Defined alternatives are evaluated against the short- and long-term aspects of three broad

criteria: effectiveness, irnplementability, and cost. Because the purpose of the screening

evaluation is to reduce the number of alternatives that will undergo a more thorough and

extensive analysis, alternatives will be evaluated more generally in this phase than during the V

detailed analysis. However, evaluations at this time should be sufficiently detailed to distinguish

among alternatives. Initially, specific technologies or process options were evaluated primarily

on the basis of whether or not they could meet a particular remedial action objective. During

alternative screening, the entire alternative is evaluated as to its effectiveness, irnplementability,

and cost.

TABLE 3.7 SCREENING EVALUATION OF ALTERNATIVES

(Shading indicates alternative screened out)

Cost

$0.2M

$22.4M

Implementability

Easy to implement.

Produces significant quantities o f water that need treatment prior to discharge.

Alternative

I. No Action

2A. Hydraulic dredging (260,000 yd3), dewatering and water treatment.

Effectiveness

Not effective at protecting human health since fish advisories can be ignored or unknown to fishermen.

Effective at reducing risk to human health and environment, no O&M required.

Alternative

2B. Hydraulic dredging (50,000 yd3), dewatering and water treatment.

3A. Mechanical dredging (260,000 yd3), dewatering and water treatment.

3B. Mechanical dredging (50,000 yd3), dewatering and water treabnent.

4. Hydraulic modification using temporaly dams, excavation (260,000 yd3), dewatering and water treatment.

5. Subtitle D landfill

6. Subtitle C landfill

7. Capping 25 acres of sediments in place.

Cost

% 9M

$20.7M

$7M

$16.9M

$ 3.2M (260,000 yd3)

$ 17.4M (260,000 yd3)

$ 7.5M

Effectiveness

Would probably not be protective of human health and the environment.

Effective at reducing risk to human health and environment, no O&M required.

Would probably IIM be protective of human health and the environment.

Effective at reducing risk to human health and environment, no 0&M required.

Could effectively contain waste, would need to evaluate individual landfill's construction.

Would effectively contain the waste.

May not reduce the bioavailability of contaminants to fish.

Implementability

Produces significant quantities of water that need treatment prior to discharge.

Water depth in SLI may pose problems if dredge needs to be barge- mounted.

Water depth in SLI may pose problems if dredge needs to be barge- mounted.

Easy to implement in middle basin, may not be as easy in lower basin.

May have difficulty finding landfills willing to take the waste.

Easily implementable.

Would greatly reduce water depth in SLI, and would probably create "islands" in SLI. Scour may be a problem. Long- term O&M required.

SECTION 4 - D o

4.J

The detailed analysis of alternatives consists of the analysis and presentation of the

relevant information needed to allow decisionmakers to select a site remedy, not the

decisionmaking process itself. During the detailed analysis, each alternative is assessed against

the evaluation criteria described in this section. The results of this assessment are arrayed to

compare the alternatives and identify the key tradeoffs among them. This approach to analyzing

alternatives is designed to provide decisionmakers with sufficient information to adequately

compare the alternatives, select an appropriate remedy for the site, and demonstrate satisfaction

of the CERCLA remedy selection requirements in the Record of Decision (ROD).

Nine evaluation criteria have been developed to address the CERCLA requirements and

to address the additional technical and policy considerations that have proven to be important for

selecting among remedial alternatives. The evaluation criteria are:

In accordance with Section 121 of CERCLA, this section provides an analysis of the

ability of the screened alternatives to satisfy the nine evaluation criteria in the N.C.P. The first

two criteria are threshold criteria:

+ overall protection of human health and the environment, and

+ compliance with ARARs.

-

A potential remedy must fulfill these criteria in order to undergo further consideration.

The next five criteria are primary balancing criteria and include the following:

+ long-term effectiveness and permanence;

+ reduction of toxicity, mobility, or volume through treatment;

+ short-term effectiveness;

+ implementability; and

+ cost.

The remaining two criteria are modifying considerations and include the following:

+ state acceptance; and

+ community acceptance.

Threshold Criteria

- Dverall Protec

Overall protection of human health and the environmental addresses whether or not a

remediation provides adequate protection over both the short-term and long-term and describes

how risks posed through each pathway are eliminated, reduced, or controlled through treatment,

engineering controls, or institutional controls. This criterion will specifically evaluate whether

each alternative provides protection as described by the remedial action objectives (RAOs).

nce with ARARs

Compliance with ARARs addresses whether or not a remedy will meet all of the

applicable or relevant and appropriate requirements of other Federal and State environmental

statutes or provide grounds for invoking a waiver. ARARs are categorized in terms of location-

specific, action-specific, and chemical-specific ARARs.

Primary Balancing Criteria

Long-term effectiveness and permanence addresses the results of a remedial action in W

terms of the risk remaining at the site after response objectives have been met. Factors which are

considered include the following:

+ magnitude of residual risk; and,

+ adequacy and reliability of controls.

Re- . .

tv. Mobilitv or Volume Throueh Treatment

Reduction of toxicity, mobility, or volume through treatment is the anticipated

performance of the treatment technologies that a remedy may employ. Factors which are

considered include the following:

+ the treatment or recycling processes which the alternative employs and the

materials which are treated;

+ the quantity of contaminants that will be treated, destroyed, or recycled;

+ the degree of expected reduction in toxicity, mobility, or volume;

98

+ the degree to which the treatment is irreversible; and.

+ the quantity and type of residual materials that will remain following treatment.

Technologies such as landfill capping that provide no treatment do not require evaluation

under this criterion.

Short-term effectiveness addresses the period of time needed to achieve protection and

any adverse impacts on human health and the environment that may be posed during the L,

construction and implementation period until remediation objectives are achieved. Factors which

are considered include the following:

+ short term risks that might be posed to the community during the implementation

of an alternative:

+ potential impacts to workers and the environment during implementation of the

alternative considering the reliability and effectiveness of protective measures;

and,

+ the time until remedial objectives are achieved

Implementability is the technical and administrative feasibility of a remedy, including the

availability of materials and services needed to implement a particular option.

The technical feasibility evaluation includes the following:

+ the ability to construct and operate the technology;

99

+ reliability of the technology;

+ the ease of undertaking additional remedial actions, if necessary;

+ the availability of off-site treatment, storage, and disposal capacity when needed;

+ the availability of services, equipment, and materials;

+ the availability of prospective technologies; and,

+ the ability to monitor the effectiveness of the remedy.

The administrative feasibility evaluation includes the following:

+ the ability to obtain approvals from involved agencies;

+ coordination with involved agencies; and,

+ property ownership and access rights issues.

The cost evaluation criterion includes estimated capital and operation and maintenance

costs, and net present worth costs.

Costs were determined from readily available sources such as Feasibility Study reports for other

sediment projects and from equipment vendors. These costs are not the actual cost of designing

and constructing the remedial action alternative, but rather costs associated with each alternative

using consistent engineering assumptions and estimating methods. Cost estimates provided in

this FS are intended to provide a level of accuracy between +50% to -30% of the actual cost.

More detailed cost estimates will be prepared during the Remedial Design phase.

Modifying Considerations

'\

Federal and State Agencies Acceptance addresses the technical or administrative issues

and concerns the support agencies may have regarding each alternative.

Community acceptance addresses the issues and concerns the public may have to each of

the alternatives. A public meeting was held in October, 1997. At that meeting several members

of the public expressed an interest in forming a community advisory group (CAG). The CAG V

was formed soon after the public meeting in October, 1997. Approximately 35 people make up

the CAG including the Mayor and City Manager. U.S. EPA and MDEQ meet with the CAG

every month to provide updates on the project.

I As with State acceptance, the criterion of community acceptance will be addressed in the

Record of Decision, after public comments on the RIIFS reports and the Proposed Plan hare been

received and evaluated by U.S. EPA. Therefore, this criterion will not be discussed further in

this document. W'

4.2 w v e s for D-

m: No Action - This alternative involves taking no additional action at the Site, but

includes fish tissue monitoring and fish advisories that are currently in place. This alternative

serves as a baseline against which other alternatives are evaluated.

101

Waste Removal Alternatives

Alternative: Hydraulic Dredging, Dewatering and Water Treatment - Alternative 2A

considers hydraulic dredging of sediments with DDT concentrations in excess of the identified

action level (approx. 260,000 cu. yds.), dewatering of sediments, addition of a stabilizing agent,

water treatment and discharge to the Pine RiverISt. Louis Impoundment. The water treatment

will be designed to meet surface water discharge requirements and will probably consist of

clarification, sand filtration, carbon filters and 1 micron bag filters. During dredging operations w monitoring will be conducted to ensure protection of workers and the community. Monitoring of

resuspension will be done directly downstream of the dredging operations. Air monitoring will

be conducted. After completion of the dredging project sediment samples will be collected to

ensure the clean-up standard has been met. The State of Michigan will continue to monitor fish

tissue levels.

Alternative: Mechanical Dredging, Dewatering and Water Treatment - Alternative 3A

considers gasketed clamshell dredging of sediments with DDT concentrations in excess of the

identified action level (approx. 260,000 cu. yds.), dewatering of sediments, addition of a

stabilizing agent, water treatment and discharge to the Pine RivedSt. Louis Impoundment. The

water treatment will be designed to meet surface water discharge requirements and will probably

consist of clarification, sand filtration, carbon filters and 1 micron bag filters. During dredging

operations monitoring will be conducted to ensure protection of workers and the community.

Monitoring of resuspension will be done directly downstream of the dredging operations. Air

102

"\ I monitoring will be conducted. After completion of the dredging project sediment samples will

be collected to ensure the clean-up standard has been met. The State of Michigan will continue

to monitor fish tissue levels.

Akm&&: Hydraulic Modification of the Pine River, Excavation of Sediments, Dewatering

and Water Treatment. Alternative 4 is similar to Alternative 3A except that temporary

cofferdams will be placed in the St. Louis Impoundment, water will be pumped from the

- cofferdam, the sediments will be excavated instead of dredged, a stabilizing agent will be added

and water will be treated prior to discharge to the Pine River. The water treatment will be

designed to meet surface water discharge requirements and will probably consist of clarification,

sa~ld filtration, carbon filters and 1 micron bag filters. During excavation operations

monitoring will be conducted to ensure protection of workers and the community. Monitoring of

resuspension will be done directly downstream of the excavation operations. Air monitoring will

be conducted. After completion of the dredging project sediment samples will be collected to

L ensure the clean-up standard has been met. The State of Michigan will continue to monitor fish

tissue levels.

Contaminated Sediment Disposal Options

- 5 : This alternative considers disposal of sediment in a commercially operated RCRA

subtitle D landfill located in the State of Michigan.

-6: This alternative considers disposal of sediment in a commercially operated RCRA

subtitle C landfill.

Conlainmen1 Option

Alternative: This alternative considers capping all the contaminated sediments in place.

Alternative 7 considers the placement of a sand cap with a stone armoring system consisting of a

20-inch coarse-grained sand cap and 5- to 7.5-inch diameter stone armor layer. Monitoring

would occur every 2-3 years and cap replenishment would occur every 5 years.

Ki

The following sections provide an individual analysis of each alternative with respect to

the seven evaluation criteria.

Descrlotlon

This alternative involves taking no additional action at the Site, but includes fish tissue

monitoring and fish advisories that are currently in place. This alternative serves as a baseline

against which other alternatives are evaluated.

Overall P P

Natural processes which would affect the Site under this altemative could include

104

\ depositibn of clean sediment on top of the contaminated sediment. However, deposition of clean

sediment since 1980 has not resulted in additional protection to human health or the environment

based on fish tissue data. Effects from biodegradation are expected to be insignificant,

particularly considering the stability of the DDT molecule. Alternative 1 is therefore not

protective of human health and the environment because of the stability and toxicity of the DDT

contamination in the sediments in the Pine River. RAOs are not achievable with Alternative I in

a reasonable timeframe. Since the remedy was implemented for the main plant site in 1984, no

L reduction of DDT in fish tissue can be documented.

e w~th 8&9Bs

Since no sediments would be removed, handled, contained or treated, and 110 remedial I

activities perfonned in the SLI, no action-specific A W R S would be triggered as a result of this

alternative. It is expected that all chemical-, location-, and action-specific ARARs would be met

by this alternative.

L

p

Under Alternative 1 the residual risks associated with potential fish consumption would

be unacceptable. Currently there are significant levels of DDT in surface sediments and

subsurface sediments in the SLI which would continue to be bioavailable to fish. In addition,

there is no practical way to restrict access to the SLI and Pine River in order to ensure no one is

eating the fish. Contaminated fish are estimated to swim 33 river miles from the St. Louis Dam

to the confluence of the Tittiwabasse River.

Adequacy and reliability of fish consumption advisories are difficult to evaluate. The

contamination in the SLI affects fish in the Pine River that migrate an estimated 33 river miles.

This is a large area to attempt to control through fish advisories and there is no practical way to

restrict access to the River. EPA's discussions with the public indicate that many people in St.

Louis are aware of the fish advisories and do not eat the fish, however, most residents have

observed people fishing. EPA has no information about the awareness of communities

downstream of St. Louis that may be fishing and ingesting contaminated fish.

. . . . n of To- or V-

Alternative 1 does not provide any active remediation of contaminated sediments in the

SLI. Therefore there would be no reduction of mobility or volume through Altemstive I .

Toxicity could be reduced by natural sedimentation, but could just as likely be increased due to

scour. Scour could expose more highly contaminated sediments.

~ ~ f e c t i v e w s s

Alternative 1 would pose no increased risk to workers or the community from remedial or

construction activities since none would be implemented.

This alternative is technically and administratively implementable since the fish advisory

is already in place and monitoring of contaminants in fish tissue data has been occurring for over

a decade.

A l t e r n a t i v e Dewatwing and W-

Alternative 2A considers hydraulic dredging of sediments with DDT concentrations in

excess of the identified action level (approx. 260,000 cu yds.), dewatering of sediments, addition

of a stabilizing agent, water treatment and discharge to the Pine RiverISt. Louis Impoundment.

The water treatment will be designed to meet surface water discharge requirements and will

probably consist of clarification, sand filtration, carbon filters and 1 micron bag filters. During

- dredging operations monitoring will be conducted to ensure protection of workers and the

community. Monitoring of resuspension will be done directly downstream of the dredging

operations. Air monitoring will be conducted. After completion of the dredging project

sedirnect samples will be collected to ensure the clean-up standard has been met. The State o i

Michigan will continue to monitor fish tissue levels.

Qverall Protect-

b Alternative 2A considers removing all sediments exceeding 5 ppm total DDT from the St.

Louis Impoundment using hydraulic dredging. Based on the human health risk assessment and

ecological risk assessment, removal of sediments exceeding 5 ppm will provide protection to

human hezlth and the environment because risk associated with the exposure pathways will be

substantially reduced. Removal of contaminated sediments are expected to produce a significant

decrease in the levels of total DDT in fish tissue, resulting in significantly reducing human health

effects from consumption of contaminated fish and reproductive effects to fish-eating birds. The

second exposure pathway, direct contact with contaminated sediments would also be eliminated

107

by removing sediments exceeding 5 ppm. This alternative would meet all the remedial action

objectives (RAOs).

Dredging activities would comply with the substantive requirements of the Federal Clean

Water Act and the Michigan Inland Lakes and Streams Act and State chemical-specific ARARs.

Contaminated sediments were tested by the TCLP (Toxicity Characteristic Leaching Procedure)

and determined not to be RCRA characteristic. The contaminated sediments are not considered

by EPA to be RCRA listed waste because the contamination occurred primarily from the direct

discharge of DDT process wastewaters to the Pine River. &.g 40 CFR Section 261.33(d)

comment. Waters from the dewatering process will be treated using Best Available Technology

I %AT) processes in order to comply with the substaqtive requirements under the Clean Water

Act and the Michigan Water Resources Act.

Hydraulic dredging would comply with action- and location-specific ARARs, through

appropriate management (i.e., storage and disposal) of dredged materials.

During implementation of this alternative reasonable efforts will be made to minimize

potential human health and ecological risks, as well as minimize disruption of existing natural

processes associated with remediation. Hydraulic dredging is not expected to create an

unacceptable short-term risk to human health or the environment from resuspension of

contaminated sediments based on three other hydraulic dredging projects EPA is conducting.

Turbidity monitoring conducted during these dredging projects (Shiawassee, Waukegan and

Manistique) showed resuspension was minimal. Engineering controls, such as silt curtains,

108

would be utilized to minimize concerns with resuspension.

The effects of this alternative on DDT sediment concentrations are expected to be

immediate and permanent since there are no other known potential DDT sources in the Pine

River. Dredging contaminated sediments from the St. Louis Impoundment will significantly

reduce the risk to human health and the environment from consumption of fish and direct contact

~- with sediments. Removing the majority of the DDT mass will also eliminate the threat of the

contamination moving down river. After removing sediments exceeding 5 ppm total DDT, no

additional operation or maintenance will be required for the Pine River. Fish tissue studies will

ccntinue to be conducted by the MDEQ to document levels of contaminants in fish.

Water generated as a result of sediment removal activities would be treated and

discharged back to the Pine River. The water treatment will be designed to meet surface water

discharge requirements and will probably consist of clarification. sand filtration, carbon filters

L and 1 micron bag filters.

Beduction of T o x ~ c ~ t ~ . . .

' ' v or Volu-

Sediments contaminated with total DDT are the principal threat at the site. DDT and it

congeners are highly persistent, but not very mobile. DDT and its congeners bind tightly to

organic material in the sediments. It is hydrophobic and therefore generally will not move to

surface water. After the sediments are removed from the river, a stabilizing agent will be added

to assist in dewatering the sediments and to bind the DDT even tighter to the soils. This

109

treatment will not meet the RCRA treatment standard for a U061 waste. However, as discussed

in the "Compliance With ARARs" section above. EPA has determined this is not a U-listed

waste. Therefore, EPA is not required to meet the RCRA treatment standard prior to disposal.

W - T e r m Effectiveness

The short term effects of dredging would include some resuspension of contaminated

sediments, however, based on EPA's experience with other dredging projects, resuspension

should be minimal with the use of engineering controls. During dredging operations, on-site J

workers may be exposed to DDT contaminated sediments dermally or via inhalation. These risks

will be addressed using personal protective clothing and respiratory protection. Access to

removal operations and dewatering areas would be restricted to the general public. Dewatered

sediments would be kept moist to prevent them from blowing. Air monitoring will be used to

ensure there is no airborne exposure of sediments to workers or the community. Remedial

response objectives could be achieved in two to three construction seasons.

. . Impkmnhbilitv - T e c U and Admlnlstrative

The technical ability to conduct hydraulic dredging in the St. Louis Impoundment is

considered to be excellent. Low water depths in the SLI (averaging 7 feet of water) will not

hinder hydraulic dredging. Care will need to be taken while dredging around the mill street

bridge pilings. Assuming the Agencies will be able to use the main plant site for dewatering and

water treatment operations there should be no technical barriers to implementing this alternative.

If the main plant site cannot be utilized, an alternate parcel(s) of property would be secured for

110

1 dewatering and water treatment operations. This would add additional cost and complexity to

the project because water levels in the St. Louis Impoundment may not be deep enough to cany a

barge loaded with sediments.

Since the Velsicol site is a CERCLA site, permits are not required for on-site activities;

however the substantive applicable requirements of Federal and State regulations would need to

be met. It is expected that these requirements could be met. With respect to administrative

feasibility, access to properties in close proximity to the St. Louis Impoundment will need to be

- secured before work can begin. Obtaining dredging, dewatering and water treatment equipment

should be easy as these items are readily available.

e 3A: M e c b a n i f a l and Water Tre-

DescrlDtlon

Alternative 3.4 considers gasketed clamshell dredging of sediments with DDT

concentrations in excess of the identified action level (approx. 260,000 cu. yds.), dewatering of

L sediments, addition of a stabilizing agent, water treatment and discharge to the Pine RiverISt.

Louis Impoundment. The water treatment will be designed to meet surface water discharge

requirements and will probably consist of clarification, sand filtration, carbon filters and 1

micron bag filters. During dredging operations monitoring will be conducted to ensure

protection of workers and the community. Monitoring of resuspension will be done directly

downstream of the dredging operations. Air monitoring will be conducted. After completion of

the dredging project sediment samples will be collected to ensure the clean-up standard has been

met. The State of Michigan will continue to monitor fish tissue levels.

111

Overall E n v i r m

Alternative 3A considers removing all sediments exceeding 5 ppm total DDT from the St.

Louis Impoundment using mechanical dredging. Based on the human health risk assessment and

ecological risk assessment, removal of sediments exceeding 5 ppm will provide protection to

human health and the environment because risk associated with the exposure pathways will be

substantially reduced. Removal of contaminated sediments are expected to produce a significant

decrease in the levels of total DDT in fish tissue, resulting in significantly reducing human health

effects from consumption of contaminated fish and reproductive effects to fish-eating birds. The w

second exposure pathway, direct contact with contaminated sediments would also be eliminated

by removing sediments exceeding 5 ppm. This alternative would meet all the remedial action

objectives (RAOs).

with A-

Drzdging activities would comply with the substantive requirements of the Federal Clean

Water Act and the Michigan Inland Lakes and Streams Act and State chemical-specific ARARs. 4

Contaminated sediments were tested by the TCLP (Toxicity Characteristic Leaching Procedure)

and determined not to be RCRA characteristic. The contaminated sediments are not considered

by EPA to be RCRA listed waste because the contamination occurred primarily from the direct

discharge of DDT process wastewaters to the Pine River. &s 40 CFR Section 261.33(d)

comment. Waters from the dewatering process will be treated using Best Available Technology

(BAT) processes in order to comply with the substantive requirements under the Clean Water

Act and the Michigan Water Resources Act.

112

Mechanical dredging would comply with action- and location-specific ARARs, through

appropriate management (i.e., storage and disposal) of dredged materials.

During implementation of this alternative reasonable efforts will be made to minimize

potential human health and ecological risks, as well as minimize disruption of existing natural

processes associated with remediation. Mechanical dredging is not expected to create an

unacceptable short-term risk to human health or the environment from resuspension of

contaminated sediments based on two other mechanical dredging projects EPA has completed.

.- Engineering controls, such as silt curtains, would be utilized to minimize concerns with

resuspension.

I m L T e r m e - I

The effects of this alternative on DDT sediment concentrations are expected to be

immediate and permanent since there are no other known potential DDT sources in the Pine

River. Dredging contaminated sediments from the St. Louis Impoundment will significantly

L. reduce the risk to human health and the environment from consumption of fish and direct contact

with sediments. Removing the majority of the DDT mass will also eliminate the threat of the

contamination moving down river. AAer removing sediments exceeding 5 ppm total DDT, no

additional operations and maintenance will be required for the Pine River. Fish tissue studies

will continue to be conducted by the MDEQ to document levels of contaminants in fish.

Water generated as a result of sediment removal activities would be treated and

discharged back in the Pine River. The water treatment will be designed to meet surface water

discharge requirements and will probably consist of clarification, sand filtration, carbon filters

113

and 1 micron bag filters.

. . ob111tv or Vo-

Sediments contaminated with total DDT are the principal threat at the site. DDT and it

congeners are highly persistent, but not very mobile. DDT and its congeners bind tightly to

organic material in the sediments. It is hydrophobic and therefore generally will not move to

surface water. After the sediments are removed from the river, a stabilizing agent will be added

to assist in dewatering the sediments and to bind the DDT even tighter to the soils. This

treatment will not meet the RCRA treatment standard for a U061 waste. However, as discussed

in the "Compliance with ARARs" section above, EPA has determined this is not a U-listed

waste. Therefore, EPA is not required to meet the RCRA treatment standard prior to disposai.

The short term effects of dredging would include some resuspension of contaminated

sediments, however, based on EPA's experience with other dredging projects, resuspension

should be minimal with the use of engineering controls. During dredging operations. on-site

workr:s ma! be exposed to DDT contaminated sediments dermally or via inhalation. These risks

will be addressed using personal protective clothing and respiratory protection. Access to

removal operations and dewatering areas would be restricted to the general public. Dewatered

sediments would be kept moist to prevent them from blowing. Air monitoring will be used to

ensure there is no airborne exposure of sediments to workers or the community. Remedial

response objectives could be achieved in two to three construction seasons.

114

\

The technical ability to conduct mechanical dredging in the St. Louis Impoundment is

considered to be good. Low water depths in the SLI (averaging 7 feet of water) may slow down

material handling. A mechanical dredge would be mounted on a barge for most of the dredging

operations and dredged sediments would be loaded onto a separate barge to be taken to shore for

off-loading. Because the water depths are low, draft for the barges is limited which will limit the

amount of sediment that can be moved in a barge. As with hydraulic dredging, care will need to

.. be taken while dredging around the mill street bridge pilings. Use of the main plant site for

dewatering and water treatment operations would reduce the distance sediments would need to be

transported on the barge and therefore reduce project time and costs. If the main plant site

cannot be utilized. an alternate parcel(s) of property w o ~ ~ l d be secured for dewatering and water I

treatment operations. This would add additional cost and complexity to the project because

water levels in the St. Louis Impoundment may not be deep enough to cany a barge loaded with

sediments.

Since the Velsicol site is a CERCLA site, permits are not required for on-site activities;

however the substantive applicable requirements of Federal and State regulations would need to

be met. It is expected that these requirements could be met. With respect to administrative

feasibility, access to properties in close proximity to the St. Louis Impoundment will need to be

secured before work can begin. Obtaining dredging, dewatering and water treatment equipment

should be easy as these items are readily available.

w i v e 4: H w Sediments.Dewaterin~ and W-

Descnotlon

Alternative 4 is similar to Alternative 3A except that temporary cofferdams will be placed

in the St. Louis Impoundment, water will be pumped from the cofferdam, the sediments will be

excavated or mechanically dredged, a stabilizing agent will be added and water will be treated

prior to discharge to the Pine River. The water treatment will be designed to meet surface water

discharge requirements and will probably consist of clarification, sand filtration, carbon filters

and 1 micron bag filters. During excavation operations monitoring will be conducted to ensure

protection of workers and the community. Monitoring of resuspension will be done directly

doivnstream of the excavation operations. Air monitoring will be conducted. After completion

of the dredging project sediment samples will be collected to ensure the clean-up standard has

been met. The State of Michigan will continue to monitor fish tissue levels.

Qverall Ptaes.tbn of H P

Alternative 4 considers removing all sediments exceeding 5 ppm total DDT from the St.

Louis Impoundment using temporary cofferdams in conjunction with excavation or mechanical

dredging. Based on the human health risk assessment and ecological risk assessment, removal of

sediments exceeding 5 ppm will provide protection to human health and the environment

because risk associated with the exposure pathways will be substantially reduced. Removal of

contaminated sediments are expected to produce a significant decrease in the levels of total DDT

in fish tissue, resulting in significantly reducing human health effects from consumption of

116

contaminated fish and reproductive effects to fish-eating birds. The second exposure pathway,

direct contact with contaminated sediments would also be eliminated by removing sediments

exceeding 5 ppm. This alternative would meet all the remedial action objectives (RAOs).

Excavation andlor dredging activities would comply with the substantive requirements of

the Federal Clean Water Act and the Michigan Inland Lakes and Streams Act and State

L chemical-specific ARARs. Contaminated sediments were tested by the TCLP (Toxicity

Characteristic Leaching Procedure) and determined not to be RCRA characteristic. The

contaminated sediments are not considered by EPA to be RCRA listed waste because the

contamination occurred primarily from the direct discharge of DDT process wastewaters to the 1

Pine River. & 40 CFR Section 261,33(d) comment. Waters from the dewatering process will

be treated using Best Available Technology (BAT) processes in order to comply with the

substantive requirements under the Clean Water Act and the Michigan Water Resources Act.

Excavation and/or mechanical dredging would comply with action- and location-specific

ARARs, through appropriate management (i.e., storage and disposal) of dredged materials.

Duririg implementation of this alternative reasonable efforts will be made to minimize

potential human health and ecological risks, as well as minimize disruption of existing natural

processes associated with remediation. Excavation and/or mechanical dredging is not expected

to create an inacceptable short-term risk to human health or the environment from resuspension

of contaminated sediments based on two sediment excavation projects EPA has completed.

Engineering controls. such as silt curtains and temporary coffer dams would be utilized to

117

minimize concerns with resuspension.

The effects of this alternative on DDT sediment concentrations are expected to be

immediate and permanent since there are no other known potential DDT sources in the Pine

River. Excavation andlor dredging contaminated sediments from the St. Louis Impoundment

will significantly reduce the risk to human health and the environment from consumption of fish

and direct contact with sediments. Removing the majority of the DDT mass will also eliminate

the threat of the contamination moving down river. AAer removing sediments exceeding 5 ppm

total DDT, no additional operations and maintenance will be required for the Pine River. Fish

tissue studies will continue to be conducted by the MDEQ to document levels of contaminants in

fish.

Water generated as a result of sediment removal activities would be treated and

discharged back in the Pine River. The water treatment will be designed to meet surface water

discharge requirements and will probably consist of clarification, sand filtration, carbon filters

and 1 micron bag filters.

WucLuu of To . .

wt&M&&v or Volume throueh T r a

Sediments contaminated with total DDT are the principal threat at the site. DDT and it

congeners are highly persistent, but not very mobile. DDT and its congeners bind tightly to

organic material in the sediments. It is hydrophobic and therefore generally will not move to

surface water. After the sediments are removed from the river, a stabilizing agent will be added

118

\ : to assist in dewatering the sediments and to bind the DDT even tighter to the soils. This

treatment will not meet the RCRA treatment standard for a U061 waste. However, as discussed

in the "Compliance With ARARs" section above, EPA has determined this is not a U-listed

waste. Therefore, EPA is not required to meet the RCRA treatment standard prior to disposal.

The short term effects of excavation/dredging would include some resuspension of

L-' contaminated sediments, however, based on EPA's experience with other dredging projects,

resuspension should be minimal with the use of engineering controls. Alternative 4 contains

added short-term protection from resuspension with the use of the temporary cofferdams. The

t-mporary cofferdams will contain any resuspension, and additional engineering controls could

be used with the cofferdams. like silt curtains to add additional layers of protection. During

dredging operations, on-site workers may be exposed to DDT contaminated sediments dermally

or via inhalation. These risks will be addressed using personal protective clothing and

L respiratory protection. Access to removal operations and dewatering areas would be restricted to

the general public. Dewatered sediments would be kept moist to prevent them from blowing. Air

monitoring will be used to ensure there is no airborne exposure of sediments to workers or the

ccmmunity. Remedial response objectives could be achieved in two to three construction

seasons.

. . v - Tec-

The technical ability to conduct excavation and/or mechanical dredging with temporary

cofferdams in the St. Louis Impoundment is considered to be good. Low water depths in the

SLl (averaging 7 feet of water) may slow down material handling. A mechanical dredge would

be mounted on a barge for most of the dredging operations and dredged sediments would be

loaded onto a separate barge to be taken to shore for off-loading. Because the water depths are

low, draft for the barges is limited which will limit the amount of sediment that can be moved in

a barge. As with hydraulic dredging, care will need to be taken while dredging around the mill

street bridge pilings. Use the main plant site for dewatering and water treatment operations

would reduce the distance sediments would need to be transported on the barge and therefore

reduce project time and costs. If the main plant site cannot be utilized, an alternate parcel(s) of

property would bc secured For dewatering and water treatment operations. This would add

additional cost and complexity to tKe project because water levels in the St. Louis Impoundment

may not be deep enough to cany a barge loaded with sediments.

Since the Velsicol site is a CERCLA site, pefmits are not required for on-site activities;

however the substantive applicable requirements of Federal and State regulations would need to

be met. It is expected that these requirements could be met. With respect to administrative

feasibility, access to properties in close proximity to the St. Louis Impoundment will need to be

secured before work can begin. Obtaining temporary dams, excavation, dredging, dewatering

and water treatment equipment should be easy as these items are readily available.

ve 5:

Descrlotlon

This alternative considers trucking of dewatered sediments and disposal in a

commercially operated RCRA subtitle D landfill located in the State of Michigan.

RCRA subtitle D landfills are constructed for the purpose of disposal of municipal solid

b waste. Construction requirements for bottom liners, leachate collection and monitoring are

generally not as stringent as for landfills designed to accept hazardous waste (subtitle C

landfills). The determination of how protective disposal in a subtitle D landfill would be will

depend on the mobility of the contaminants placed in the landfill and the construction I

specifications of the landfill. DDT and its congeners, which constitute the principal threat at the

site, are not very mobile. DDT and its congeners prefer to stay bound to organic matter and are

hydrophobic. If the landfill is constructed with bonom liners and leachate extraction, it is likely

b that this option would he protective of human health and the environment. The direct contact

exposure pathway would be eliminated with this alternative.

'3n.uzhance with A&BBs

Contaminated sediments were tested by the TCLP (Toxicity Characteristic Leaching

Procedure) and determined not to be RCRA characteristic. The contaminated sediments are not

considered by EPA to be RCRA listed waste because the contamination occurred primarily from

the direct discharge of DDT process wastewaters to the Pine River. & 40 CFR Section

121

261.33(d) comment. Transportation of the waste material will maintain the proper permits and

adhere to the applicable standards for proper identification number, reporting and manifest

system as established by the U.S. and Michigan Department's of Transportation. This alternative

would meet the chemical-specific, action-specific and location-specific requirements set forth in

federal and state laws.

The amount of contamination on the site would be reduced by removal and disposal of

contaminated sediments. Residual contamination that would remain after completion of

remedial activities would be minimal and would be below acceptable levels. The long-term

acTfcctiveness of this alternative would be a function of the long-term integrity of the landfill

chosen for a disposal site. If the waste is disposed of in a properly designed facility, the long-

term effectiveness would be expected to be good if the landfill is well maintained over time.

W c t i o n of Toxic~tv. Mob . .

ility or V o l u m e u g h Treatmw!

After the sediments are removed from the river, a stabilizing agent will be added to

assist in dewatering the sediments and to bind the DDT even tighter to the soils. This treatment

will not meet the RCRA treatment standard for a U061 waste. However, as discussed in the

"Compliance With ARARs" section for Alternatives 2A, 3A and 4 above, EPA has determined

this is not a U-listed waste. Therefore, EPA is not required to meet the RCRA treatment standard

prior to disposal. It is not anticipated that the landfill will provide any additional treatment prior

to final disposal.

122

~\ I

With this altemative, there could be dust emissions and direct contact hazards during

handling activities to which workers and the surrounding community could be exposed. To

address this threat, dust control measures, such as keeping the sediments moist, will be

implemented, and workers will wear protective clothing to reduce the risks associated with

remediation. There will also be a higher than usual volume of construction traffic because of the

transport of materials either to or from the site. Also with any type of transportation there is a

L potential for traffic accidents to occur. To address this threat. measures will be taken to use a

reputable transport company, and route truck traffic away from residential areas to the extent

possible.

This altemative is technically feasible. Subtitle D Landfills do exist within the State of

kiichigm, within a reasonable transportation distance. However, it should be noted that even

L though there are subtitle D landfills that could accept the waste, they may be reluctant to accept

sediments containing the highest concentrations of total DDT. EPA would consider sending

lower concentration sediments to a subtitle D landfill and sediments with higher concentrations

of total DDT to a subtitle C landfill. Other potential implementation problems could include

negative public reaction to truck traffic and noise.

-

e 6: RCRA Sub-

Q.wmUQn

This alternative considers trucking of dewatered sediments and disposal in a

commercially operated RCRA subtitle C landfill located in the State of Michigan.

RCRA subtitle C landfills are constructed for the purpose of disposal of industrial

hazardous waste. Construction requirements for bottom liners, leachate collection and

monitoring are more stringent than for landfills designed to accept municipal waste (subtitle D

landfills). The determination of how protective disposal in a subtitle C landfill is will depend on

the mobility of tht. contaminants placed in the landfill and the construction specifications of the

lw.dfill. DDT and its congeners, which constitute the principal threat at the site, are not very

mobile. DIjT and its congeners prefer to stay bound to organic matter and are hydrophobic. If

the iandfill is constructed with bottom liners and leachate extraction, it is likely that this option

would be protective of human health and the environment. The direct contact exposure pathway V

would be eliminated with this alternative.

Contaminated sediments were tested by the TCLP (Toxicity Characteristic Leaching

Procedure) and determined not to be RCRA characteristic. The contaminated sediments are not

considered by EPA to be RCRA listed waste because the contamination occurred primarily from

the direct discharge of DDT process wastewaters to the Pine River. & 40 CFR Section

124

\ 261.33(d) comment. Transportation of the waste material will maintain the proper permits and

adhere to the applicable standards for proper identification number, reporting and manifest

system as established by the U.S. and Michigan Department's of Transportation. This alternative

would meet the chemical-specific, action-specific and location-specific requirements set forth in

federal and state laws.

L The amount of contamination on the site would be reduced by removal and dispsoal of

contaminated sediments. Residual contamination that would remain after completion of

remedial activities would be minimal and would be below acceptable levels. The long-term

effectiveness of this alternative would be a function of the long-term inregrity of the landfill 1

chosen for a disposal site. Since a permitted Subtitle C landfill is built and maintained for

disposal of hazardous wastes, the long-term effectiveness is expected to be good if the landfill is

well maintained over time.

L

Reductinn of TOW- . . . .

After the sediments are removed from the river, a stabilizing agent will be added to

assist in dewatering the sediments and to bind the DDT even tighter to the soils. This treatment

will not meet the RCRA treatment standard for a U061 waste. However, as discussed in the

"Compliance With ARARs" section for Alternatives 2A, 3A and 4 above, EPA has determined

this is not a U-listed waste. Therefore, EPA is not required to meet the RCRA treatment standard

prior to disposal. It is not anticipated that the landfill will provide any additional treatment prior

125

to final disposal.

With this altemative, there could be dust emissions and direct contact hazards during

handling activities to which workers and the surrounding community could be exposed. To

address this threat, dust control measures, such as keeping the sediment moist, will be

implemented, and workers will wear protective clothing to reduce the risks associated with

remediation. There will also be a higher than usual volume of construction traffic because of the

transport of materials either to or from the site. Also with any type of transportation there is a

potential for traffic accidents to occur. The risk will increase with distance traveled to the

S~ibtitle C Landfill. To address this threat, measures will be taken to use a reputable transport

company. and route truck traffic away fro111 residential areas to the extent possible.

. . . . htv - T e b l and

This altemative is technically feasible. Subtitle <: Landfills do exist within the State of

Michigan. within reasonable transportation distances. Subtitle C landfills should have no

restrictions on taking this waste. Other potential implementation problems could include

negative public reaction to truck traffic and noise.

-

Alternative 7: C-s in Place

Descrlotlon

This alternative considers capping all the contaminated sediments in place. Alternative 7

considers the placement of a sand cap with a stone armoring system consisting of a 20-inch

coarse-grained sand cap and 5- to 7.5-inch diameter stone armor layer. Monitoring would occur

every 2-3 years and cap replenishment would occur every 5 years.

u

Capping would provide adequate protection for the dermal contact exposure pathway. It

is no! certain whether or not capping would reduce concentrations of contaminants in fish tissue

to levels that would be protective of human health and the environment because the biological

uptake mechanism is not known. Sediment sampling has documented that the majority of the

mass of total DDT occurs in sediments that are deeper than 6 inches and also that concentrations

4 of total DDT in the top 6 inches has decreased since 1980. However, fish tissue data shows that

levels of total DDT may be increasing, but more likely remain at similar levels as in the 1980's.

Lower levels of contaminants in the top 6 inches of sediment should result in lower levels in fish

tissue, but this is clearly not happening in the Pine River. Therefore, it is possible that total DDT

below 6 inches is bioavailable to fish. Therefore there is a significant amount of uncertainty with

whether or not a cap would reduce the concentration of total DDT in fish tissue to an acceptable

level.

w ~ t h A w

Since no sediments would be removed, handled, contained or treated, many of the

ARARs will not be triggered. It is expected that all chemical-, location-, and action-specific

ARARs would be met by this alternative.

Residual risk to human health and the environment after the cap is installed is uncertain.

As discussed in the "Overall Protection of Human Health and the Environment" section for this

alternative, capping may not reduce the concentration of total DDT in fish tissue to an acceptable

level. The only way to know how effective capping will be would be to conduct monitoring of

fish contaminant levels after installation of the cap. The cap would be zffective at eliminating

the dermal contact exposure route, however, the cap would need to be replenished as nzeded due

to scour. A cap is not considered to be permanent, it would need to be maintained as the river

scours it away. If no maintenance occurred, the cap eventually would be eroded away by the

river.

W c t ~ o n of Toxicitv. Mobilitv or V-

This alternative does not provide any active remediation of contaminated sediments.

Therefore there would be no reduction of mobility or volume by this alternative. Toxicity could

be reduced by capping, but there is much more uncertainty with this alternative than there is with

the dredging of excavation alternatives.

There should be no increased risk to the community during cap installation. Cap

installation will cause resuspension of contaminated sediments, just as in the dredging or

excavating alternatives. Engineering controls would be utilized to reduce resuspension.

Remedial response objectives could be achieved in one construction season.

L Implementation of a cap may create "islands" in the St. Louis Impoundment due to low

water depths. The bathymetry survey EPA conducted indicates that significant portions of the

St. Louis Impoundment have water depth of less than 5 feet. Capping the contaminated

sediments in place will reduce the holding capacity of the St. Louis lmpoundment and preclude I

the uossibitity of ever dredging the lmpoundment to increase the holding capacity. In atldition,

EPA anticipates there would be technical difficulties in implementing a cap sincz the capping

matefials viould need to be applied from a barge in some areas of the Impoundment. Low water

L levels create draft problems for barges.

The capital, operations and maintenance (O&M) and 30 year present worth costs for each

alternative are presented below. A discount rate of 8% was used. Detailed cost estimates are

located in Appendix B.

L7: Capping 1 $ 7.5M ( $30,100 1 $ 7.84M

u p v

Alternative 1, the No Action alternative, would not provide adequate protection of human

health or the environment. The risk assessment documents that unacceptable risk would occur to

d humans and is occurring to fish-eating birds if fish are ingested from the Pine River. These risks

cannot be adequately addressed through fish advisories, especially for fish-eating birds.

Therefore, the No Action alternative acts as a baseline to compare Alternatives 2.4, 3 4 4 and 7

agains!. Alternative 5 and 6 cannot stand alone, and must be paired with one of the sediment

removal options.

Alternatives 2A, 3A and 4 are very similar, they all entail the removal of contaminated

sediments above 5 ppm total DDT. The only difference between these alternatives is the method

'1 / for removal of the sediments. Alternative 2A considers hydraulic dredging, Alternative 3A

mechanical dredging, and Alternative 4 considers excavation. All of these removal methods are

implementable at this site. EPA prefers Alternative 4 over alternatives 2A and 3A because

excavation is the most efficient way to remove sediments and will produce the least amount of

water that will require treatment. Mechanical dredging would produce more water, but also

would be efficient. Hydraulic dredging would produce significant amounts of water for

treatment and therefore is the least favored of the three removal methods.

-, Alternatives 5 and 6, disposal in a Subtitle D and C landfills respectively, are both

considered to be favorable. Subtitle C landfill will be used to dispose of the highly contaminated

sediments and a Subtitle D landfill will be considered for disposal of less highly contaminated

sediments. This maintains flexibility. I

Capping the contaminated sediments in place, Alternative 7, is least favored due to the

significant uncertainty with the effectiveness of this option at protecting human health and the

environment The effectiveness of capping in reducing risk is based on how the contaminants

i . become bioavailable to fish. Since this mechanism is not known, the only way to ensure the

contaminants are not taken up by fish is to remove the contamination. If this Alternative was

selectcd and implemented and then found not to be effective at reducing contaminant levels in

fish tissue, EPA would have to reconsider the remedy and potentially select one of the removal

alternatives instead. This would significantly increase the costs overall, since not only would

EPA have to remove the cap, but also the contaminated sediments. In addition, capping poses

other problems for the St. Louis Impoundment. If a cap is placed over the contaminated

sediments the Impoundment will never be able to be dredged to increase holding capacity or

water depth. In addition, the cap will reduce the holding capacity of the Impoundment and create

"islands" where water levels are low. DDT and its congeners are very stable compounds. A

river is a very dynamic and thus unstable environment. Capping in place a very stable compound

in a very unstable environment means the potential threat of a release will remain indefinitely.

For all these reasons. removal of contaminated sediments are favored over capping in place.

45 ves 4.5 and 6 )

U.S. EPA Region 5 recommends Alternative 1: ttydraulic Modification of the Pine River, u

Excavation of Sediments, Dewatering and Water Treatment and disposal of contaminated

sediments in either a RCRA Subtitle D or C landfill, Alternatives 5 and 6. EPA believes

Alten~atives 4, 5 and 6 represent the best halance of the r:ine criteria.

FIGURES

-

Velsicol Chemical Corporation (Pine River) Superfund Site Figure 2-1

St Louis, Michican

Figure 2-2

Pine River, Chippewa River, Tittabawassee River, Saginaw River and Bay

StreetMap USA Highway

/V Primary road /V Secondary road L_i Water body F------,~ . ? , Park .i; . J

Velsicol Chemical Corporation Su~erfund Site

U S EPA

?E5

~elsicol Chemical Corporation r Sunerfund Site Figure 2-4 I

U S EPA

'2%"

-

Velsicol Chemical Corporation Figure 2-5

@LO E L , r D U S EPA

Reaim 5 m98

@seinnl d ivslvmW7 pnenv ap

,,,, "," ,,,,,,,,,,,,,,,, ,, ,, ....- ~~

Velsicol Chemical Corporation Figure 2-6

US EPA Regm 5 M9198

cgml d l v e l u a 7 pneovap

~m .

Velsicol Chemical Corporation (Pine River) Superfund Site Figure 2-7

1980 NElC Sediment Sampling Survey

In June of 1980, by the request of the USEPA Region 5, Enforcement Division, the NElC conducted a limited sampling survey of the Pine River. At a depth interval of 13 to 23 inches, in one of the sediment core samples, a maximum total DDTconcentration of 44,000 ppm was detected .

+ 1980 data (NEIC, USEPA)

0 Velsicol Chemical Corporation

U S FPA Regm 5

- -

Velsicol Chemical Corporation (Pine River) Superfund Site S t Louis. Michiaan

Figure 2-8

1982 NElC Sediment Sampling Survey

In November of 1981, the USEPA Region 5 and the NElC conducted additional sediment sampling to supplement the June 1980 sampling survey. The survey was needed to help define the areal and vertical distribution of the DDT contamination in the Pine River. The maximum concentration of total DDT detected was 26,000 ppm from a 16 to 28 inch depth interval.

+ 1982 data (NEIC, USEPA) a Velsicol Chemical Corporation

U S EPA Region 5 '&~,,<, 1,s

t APPENDIX A

Velsicol Chemical Corporation (Pine River) Superfund Site Figure 2-9

1996 GLNPO and MDEQ Sediment Sampling Survey

In May 1996, GLNPO and the MDEQ, Surface Water Quality Division conducted another sediment sampling survey. The survey was conducted with the use of the GLNPO's Muddpuppy. A maximum total DDT concentration of 1,175 ppm was found in one core sample at depth interval 6 to 28 inches.

+ 1996 data (GLNPO, MDEQ)

0 Velsicol Chemical Corporation

U S EPA RBgiCn 5 mEa

Velsicol Chemical Corporation (Pine River) Superfund Site S t Louis. Michiaan

Figure 2-10

1997 USEPA, GLNPO, & MDEQ Sediment Sampling Survey

In July 1997, the USEPA, Region 5, GLNPO and the MDEQ conducted a second sampling in the Pine River and the Impoundment area. The survey was intended to supplement the May 1996 survey and provide additional information as to the nature and extent of the DDT contamination in the Pine River. A total DDT maximum of 32,600 ppm was detected in one sample at depth interval 6 to 42 inches.

' u

+ 1987 data (USEP4 GLNPO, MDEQ) 0 Vslslcol Chemical Corporation

+ < " b",

U S EPA

Sediment Data Summary Table

LOCATION j DATE|

1980

RSS 1RSS-?RSS 3KSS-4RSS 5RSS-6RSS 6RSS /RSS 8RSS 9RSS- 9

KSS-10

6/2/006/2/806/2/806/2/806/?/806/2/806/2/806/2/606/2/806/7/BO6/2/806/3/80

ST DEPTH(inches)

0 1)0 00 00 00 03 i;: 3 50 00 00 00 0

0 0

END DEPTH(inches)

/ 0'2 0.' 0

1 0 0

1 1 013 '.,

? ( 0

10 0

8 018 0

^8 0

4 0

O,P'DDT

(ug'g)

0 0040 0040 0100 0040 200

650 00017000 000

/60 0000 590

1 300 0000 0040 070

P,P'DDT

(ug'g)

0 0040 0100 02000040 400

2000 00024000 0001200 000

5 5001900 000

0 0040410

Sum 'DOT(US/9]

0.0080.0140.0300.0080.600

2650,00041000.0001980.000

6.0903200,000

0.0080.480

O.P'DDE

(ug/g)P,P'DDE

(ug'g)

0 02000300 0100 0900 620

260 0001300 000

11 0001 400

80 0000 0100 060

Sum 'DDE(ug/g)

0.0200.0300.0100.0900.620

260.0001300,00011.0001.400

80.0000.0100.060

O.P'DDD(ug'g)

P,P'DDD(ug/g)

0 0400 0500 0100 ?801 400

1800 0001400 000340 000

5 8001 1 0 0000 00?0760

Sum 'ODD(ug/g)

0.0400.0500.0100.2801.400

1800.0001400.000340.0005.800

110.0000.0020.260

Total DOT(ug/g>

0.0680.0940.0500.3782620

4710.00043700.0002311.000

13.2903390.000

0.0200.800

HBB(ug/g)

0 0050 0100 00500800 130

540 000120 000190 00031 00020 0000 0050 300

PBB<"9'g)

0,010.010,010.380,29

270.0024007,801,402.500010.03

1981

01 101 202-102 ?03 103-203 304-104 705 1Or) 705 305-406-106 206-306 4Of 107-207.30 / - 4OB 108-2OB-309-109 ?09 309-410-110-210-31 1 - 111-717-117-212 3

11 /811 1 / 8 11 1 / 8 11 1 / 8 111/8111/811 1 /f! 11 1/8111/811 1 / 8 111/8111/8111/8111/811 1/8111/8!11 /8111/8!1 1/8111/811 1/811 1/811 1/811 1 / 8 iM/8111/8111/8111/8111/8!1 1/8111/811 1/8111/8111/811 1/811 1 / 8 1

0

404

04

160404162804!6?8

0

4

1b28i]

4

16

0

4

U-

78

0

4

16

0

4

0

4

16

4

13

4

1 /

4

1(3

24

4

13

n16

2840A

167832416283641!'.784167834416744

164

16

30

0 0250 0?50 1000 3600 0750 7500 490

32 0004 8000 1100 220

110 00000250 1900 2100 0500 0504 6002 500

7300 0001 1001 000

140 0001400 000

! 60032 0006 5000 39004802 5002 5000 4703 6001 1007 0000 075

0 1800 0253 8005 30006101 2006 400

200 00047 00011 0007 200

790 00000250 8401 6002 2000050

64 00074 000

11000 0002 00011 000

890 0003200 000

22 000130 00018 0001 0003 00025002 5004 9008 3003 9003 0000 025

0.2050.0503.9005.6800.8351.4506.890

232,000 r

51.80011.1107.420

900.0000.0501.0301.8102.2500,10068.60076.500

18300.0003.100'12.000

1030.0004600.00023.600162.00024.5001.3903.4305.0005.0005.37011.9005.0005,0000.050

0010001000250 060002500500 120027000500 0601 20022000010002500800240002503103 800

130 00000600 0250025

21 0000 12000250 02500250 0251 0001 0000 13002800 1000 1900 010

0 0 7 00 1000 3100 48003701 1001 0007?007 20004802 8005 30000100 1800340068000251 8009 700

160 00000502 100

22 00047 0000 6404 5000 0250 0250 1701 0001 00006100 7400 3900 7500010

0.0800.1100,3350.5400.3451.150

' 1.1202,4707.2500.5404.0007.5000,0200.2050.4200.9200.0502,11013,500

290,0000.1102,125

22.02568.0000.7604.5250.0500.0500.1952,0002.0000.7401.0200.4900.4400.020

0 0800 1200 2200 2200 2204 2004 80012 00032 0000 6404 200

22 0000 0250 32006202 10000509 7007 000

340000006806000

700 0002000 000

2 300180 00027 0007 5000600

275 0004 0004 0008 0007 900<! BOO0025

0 1000 1300 5800 5800 57012 0001200020 00037 0001 5008 800

58 0000 0251 10006602 6000 050

24 000220 000

3700 0000 85017 000

1100 0002700 000

6 500260 00026 0001 6001 500

1 /5 0003 800/ 000

12 0006 4006 7000 075

0.1800.2500.8000.8000.79016.20016.80032.00064.0002.14013.00080.0000.0501.4201.2804.7000.100

33.700227.0007100.000

1.53023.000

1BOO.OOO4200.000

8.800440.00053.0004.1002.100

450.0007.80011.00020.000e.30011.0000.050

0,4650,4105,0357,0001.77018.60024.810266.470123,05013.79024.420

987 5000.1202,6553.5107,8700.250

104410317.000

25890.0004.74037.125

2852.0258868.000

33.160606,52577.55055405.775

457.00014,80017.11032.92014.79016.4400.120

32000 4201 0001 1000 9600 5000 05015 00090 00092 0006 2000 2500 250

12 00028 0000 9200 2500 250

9300 000100 0001 000

2600 0001800 000

0 250140 00024 0000 2500 250

55 000440 00014 00097 000

610 00090 000170 0000 250

2.8000.4601.0000.7600.8400.5000.050

330.00023.0000.9400.2500.2500.2502.2000.5600.2500.25014.00064.00012.5000.25058.0000,2500.25018.00018,0000,2500,25014.00066.0002.5004,80021.0005,0008,0000.250

LOCATION DATE:

1996

ST DEPTH(inches)

04162840041G041G.'84004

'6

,'tf

;)4'6

28

40

L)

4

-604

Ibf)

4

16

0

4

16

U

4

• t ;3

4

:i4

• 605

• f )28

0G

"?')0.1

:i"

END DEPTH(inches)

4

1628404641628416284046416.'4424162B4045416354163441622

4162/41621414

416234162834

G35636

21366

O.P'DDT(ug/g)28000 250

30 000700 0000 400

140 000080000250 7400050

1100 000530 000

0 0503 000

13 0002 4000 050! 200005010 000C 02500251 8000 0501 2000 8100 05014 0000 2 1 01 0000 0250 1801 2 0000 0500 1603 1000 02502000 5000 0500 500005002201 00002500025

4500470000

4700VOOO21000

55026000

P.P'DDT

fug'g)5 0002 000

860001100 000

1 1001800 00010000002576001 GOO

1 200 0001000000

0 0502000012 0001 2 0000 48014 0001 800

30 000002500257 800005019 0004 0003 200

64 0003400100000 0256700

210 0000 100270018 00000252 3002 3001 1007 0000 7402000

38 0009 7000 025

Sum 'DOT(ug/g)7.8002.250

116,0001800.000

1.5001940,00010.8000,0508,3401.650

2300.0001530,000

0,10023.00025.00014.4000.53015.2001,660

40.0000,0500.0509,6000,10020,2004.8103.250

78,0003.61011,000O.OSQ6.880

222,0000,1502,86021,1000.0502.5002-8001,1507.5000,7902.22039,0009.9500.050

450047000047001100021000

55026000

O.P'DDE(ug/gl0 0700 1500 025

40 0000 12093000 120C 010C 120C 320

90 00035 00000250 0250 1400 6600 1800 060022034000 01000100 1000 0251 0000 10000250 56000801 0000 0100 1104 0000 02500602 6000 0100 0602 2000 0604 5000 1900 0800 7003 3000 010

13025000

260250

?500i>0

370

P,P'DDE(ug/g)0 3100 7400025

32 0000060

23 0000 2800 0100 4401 000

66 000370000 0250 4100 5500 8000 I GO0 2 7 00 8204 600001000100 29000251 4000 2700 0251 10002801 6000 0100 3806 0000025026030000 0100 2602 6000 3205 2000 3000 3601 8004 0000010

Sum 'DDE(ug/g)0,3800.8900.05072,0000,18032,3000,4000.0200,5601.320

156.00072.0000.0500.4350,6901.4600.3400.3301,0408.0000.0200.0200,3900,0502.4000.3700.0501.8600,3602.6000.0200.49010.0000,0500.3205.6000,0200,3204.8000.3809JOO0.4900,4402,5007,8000,020

13025,000

260250

2,50050

370

0,P'DDD(ug/gt2 0003 800

46 0001500000

3 400740 0007 00000254 1005 700

1500 0001200 000

0 2002 5001 400

1 8 0004 8002 0001 100

GO 0000 1200 0254 5000 120

48 0003 4000 160

28 0002 300

40 0000 0251 700

170 0000 5002 000

88 00000252 00078 0002 300

160 0005 1001 600

13 000150 0000025

1500680000

73001700

43000830

6600

P,P'DDD(ug/g)4 7009 200

£2 0001400 000

4 4001300 000

13 0000025-' SOO12 000

1400 0001 500 000

0 29012 0003 400

;.V' oooi- i!UO5 2001 800

120 000C 210C 0256 2000240

50 0005 6000 b10

34 0005 000

35 0000 0253 900

160 0004 6004 200

84 0000 0254 20070 0004 800

1 70 0009 6003400

32 000140 0000025

Sum 'ODD<U9/9>6.70013.000108.000

2900.0007.800

2040.00020.0000.05011.90017.700

2900.0002700.000

0.49014.5004,80038.0009. BOO7.2002.900

210,0000.3300.05010.7000.36098.0009.0000.67062.0007.30075.0000.0505.600

330.0005.1006.200

172.0000.0506,200

148.0007.100

350.00014,7005.000

45.000290.0000.050

1,500680,0007,3001,70043,000

8306,600

Total DOT(ug/g)14.88016.140

224,0504772,000

9.4804012.30031.2000.120

20.80020.670

5356.0004302.000

0.64037.93530.49053.86010,67022.7305.790

258.0000,4000,12020.6900.510

120.60014,1803.970

141.66011.27088.6000.12012.970

562.0005.3009.380

198.7000.1209.020

155.6008.630

36720015.9807.660

86.500307.7500.120

6,1301,175.000

12,26012,95066,5001,430

32,970d We

HBB<ug/<j)44 OOG

hOO 00028 0002 5000 2505 70002500 050

80 000GGO 00054 00044 0000 250

86 000220 000

0 ;"iCU JM>

5;> 0001 20 000

1 9000 0500 0504 30C0 5800 2505 0000 8100 250

34 00042 0000 050

82 00028 0000 250

54 00032 0000 050

52 00039 00035 00048 0000 250

1 80 00022 0000 5000 050

6000240000

7703200075004507500

!,i;;ol\dc;.-;s\S

PBB(ug/g)4.20025.0001.0002.5000.2502.7000.2500.0504.00016.0001.000

12.5000.25012.0006.5000,2500.2505.3001.6000.2500.0500.0251.2000.2500.2501.3006.8000.2503.0004.8000.05034000.2500,2503.4000.5000.0503.3000,5002.1005.2000.2504,4000.2500.5000.050

24029006309309005801900

'"•nary iis

DATE ST-DEPTH END-DEPTH 0,P'DDT F, JDT Sum'DDT 0,PD (~nches) (Inches) (uglgl ("gig) (Wgj - - - - ("gig)

6 28 7400 74w 710 10196 6 29 230000 259000 1900 10196 23 50 18000 18WO -- .- 630 10196 0 6 18000 l8OW 290 10196 6 24 5600 m?U 690 10196 14 4 1 1500 15W 60 10196 0 6 2800 28W 150 10196 0 6 3300 3300 120 10196 6 10 78000 78WO 7000 1019h 30 14 150 160 170

LOCATION

19202020

Oownstrea'nDowTstreariDownstreamDownstreamDownstream

1997

11122

2335556g

6B7

/7

889910101010111 11/121313131314141515'516161617'.7

Page 4

DATE

1 0/9610/961 0/9610/961 2/961 ?/9612/961 2/961 2/96

7.'977/977,'977/9 '7/977/977,977; 577/977/977/977/977/977,97

7,977,57

7i977i977,57li 9 77 (97,'/977,977,977,977,977/977,9/7/977 , 9 ?7/977/977/977/977/977,977,977/9 77/977/977/9 77/977/977/97

ST DEPTH E(inches)

4606

29i.McGregor Road.i.Bagley Roadi.Magrudder Road,i9 Mile Road(Meridian Road.

06

4206

42060G3006

42780636a6060G

42780G

0

G06

42'IS,0G0G

4206

420G

•40 DEPTH(mches)

676

2957

34 35' 50"84 34' 33"84 30' 29"84 25' 42",84 22' 09",

642706

42776

366

30466

4278956

36606186

316

427811!

6326

326

4278886

366

42526

42766

24

O.P'DDT

(ug(g_)120

75002200022000

43 25' 47")42 27' 00")43 29' 33")43 32' 09")43 33' 49")

0450 710 570430 750 5 10 560250 520 300720 510 580 540480570 540.460 220 340450 5 70 540500 540460 550 410 520 660 440680 510 400 73

360 002300

9100 002300 00

0790 360 590 46

40 00

P.P'DDT(ug'9)

0450 710 570 770 750 510 560 810 520 300 720 510 580540 480 570 840 460220 340 450 570 540 500540 460 550410 940 38036

42000 510 409 00

1100 0026 00

15000 001900 00

12006 801 500 94

40 00

Sum 'DOT(ufl/9)12075002200022000

0,9001.420, iS,1.1461,2001.5001.0201.1201.0601,0400,6001,4401.0201.1601.0800.9601.1401.3800.9200.4400.6800.9001.1401,0801.0001.0800.9201,1000.8201.4601.0400.800426801.0200,800 :9.73Q,

1460,00048.009,

241 6o;0004200,000

12.7907,1602.0901.400

80.000

O.P'DDE

(ug'fl)120430

25100970

0 450 710 570430 750 510 560250 5 20 300720510 580540480570 540460 2 20340 450570540.5011 006600 550 410 520660440680 5104007330 002300130 0066000790360 59046

40 00

P,P'DDE

(ug'g)

0450710 5 70430750 5 10560250520300720 510 580 540 480 570 460460 2 20340450570780263 7 01 800550410920 660 443600 510 401 50

30 002300

270 00100 000610980 590 46

40 00

Sum 'DDE<ug/g)_120460

2,900970

0.9001J20171400,8601.5001,0201.1200,6001,0400.6001,440

,1,0201.1801,0800.9601,1401,0000.9200,4400.6800.9001,1401.3200.76014.7008.4001,1000.8201,4401.3200.8604.2BO1.0200.8002.23060.00046.000400.000166.000

1.4001.3401.1800.92080.000

O,P'DDD(ug/g)

1802300

7700012000

0450 710 570 4 30 750 510560 250 5 20300720 510 580 540 480 570 540460 220 340450570540 2108804604!0 533402 200 442900 510 40073

67 002300

2000 00340 00

0438602200 46

230 00,•

P.P'DDD(ug'g)

0 450 7 10630430 750 5 10560250210300670 5 10 580 540 480280540460 2 20 340 970572 000 604 100 4 512 001 30

520023 000 829 800 400 4011 00

120 0027 00

6100 00520 0019 0016 004 302 30

280 00

Sum 'ODDGMM.._.__160

2.30077.00012.000

0.9001.4201.2000.8601.5001.0201.1200.5000.7300.6001.3901.0201.1601.0800.9600.8501.0800.9200.4400.6801.4201.1402.5400.8104.9800.91012.4101.830

55.40025.2001.26012.7000.9100.80011.730187.00050.000

8100.000660.00019.43024.6006.5002.760

510.000

Total DOT HBB PBB(ug/g) <ug/g) (ug/g)

420 120 58010,260 7400 2100

101,900 1300 90034,970 200 500

566 ug/kg1l7ug/kg259 ug/kg143 ug/kg

<100 ug/kg

2.7004.2603.4802.9204.5003.0603.3602.0602.8101.8004.2703.0603,4803.2402.8803.1303.4602,7601.3202.0403.2203.4204.9402.57020.76010.23014.6103.47058.30027.5602.94059.6602.9502.40023.690

1707.000145.000

32600.0005226.000

33.62033.1009.7705.0BO

670.000d \velsicol\docs\Siimmary xls

B L A N K SPACES REPRESENT FIELDS IN WHICH N O DATA W A S REPORTED

Plne River Contamlnation Survey S t L o ~ i s . Michigan (June 2-6, 1980) EPA~33012-80Ml31 (October. 1980) R. ForbaiNElClUSEPA

Summary of Pme River Sediment Samplmng Survey St Louis, Mlchlgan (November 20 22, 1981) EPA.33012-80 001 (April, 19821 R ForbalNElCfUSEPA

Status of the St. Louis Impoundment in the V!clnlly of the Former Velsicol Chemical Company Gratlot County, Mlchlgan. MDEQfSullace Water Quality Dlvis8onlStaff Repoll, October 1996 Page 5 ti ! ~ ~ l ~ ~ ~ ~ l \ d i ~ i i l S u n ~ m a r y x ' s

Fish Data Eiumniary Table

C'"""E SPECIES STYPE LENGTH WEIGHT FAT DDECONC DDDCONC DDTCONC TOTALDDT PBBCONC

(ems) (sms) (percent) (pprn) ( P P ) (PPm) ( P P ~ ) ( P P ~ )

= = = Gratct Co below St L L C L J S Dan:

Grat~ot C r below St I.OUIS Dam

Gralot Cc belo* St Lous Dam

Gratlot Cc belo& St louls Dam

G,atot C c below St 1 . 0 ~ s Dam

Gral~ot Co below St lou is Dam

Gratot Ca below St I.ouls D;im

Gratot Co below St l o u ~ s Dam

Gratlot Co below St l a u s Dan1

Gratot Co, below 31 L o u s Dam

Gratot Co below St L o m Dan1

Giatot Co, below St Louis Dam

Gratot Co below :St Lous Dam

Gratot Co below :St L O U I S Dam

Glatiot Co below St L O U I S Dam

Gratiot Co below !St L O U I S Dam

Gratot Co Deow !St Loas Dam

Gratot Co below !St La.ts Dam

Gratot Co, oeow !St L o ~ s Dam

Grattot Co oelow :St Lods Dam

Gratiot Ca 3elow St L o ~ s Dam

Grat~ot Co selow !St 10.1s Dam

Gratot Co i e o w !St L ~ J S Dam

Gratot Co selow !St Louts Dam

Giatot Co 3eow !St Lo8~1s Dam

Gratot Co, selow !St LOUIS Dam

Gratot Co i e o w !St Louis Dam

Gratot Co ,elow !St Lo~dts Dan,

Gratot Co, selow !St Lo.~is Dam

Gtatot Co seow !St L ~ ~ . J ! s Darn

Gratot Co aelow !it Lous Dan,

Gratot Co below St Lous Dam

- j583 Carp Fs 55 9 281: O W 6 0.016 0 100e

1983 Carp Fs 50 8 3402 0.061 0.061 0.100<

1983 Carp Fs 6 1 3674 0.02% 0.000 O.lOO< 1983 Carp Fs 43 2 1451 0.076 0.076 0 1 OO<

1983 Carp Fs 40 6 680 0.100 0.100 0.100<

1983 Carp Fs 0,100<

1983 Wtilte Sucker F 38 1 680 0810

1983 Wh~te Sucker F 33 499 0.055 0.055 0.220

1983 W h ~ t e Sucker F 33 499 0.060 0.060 0.lOOc

1983 Whlte Sucker F 30 5 408 0.130 0.130 0.460

1983 Whte Sucker F 27 9 434 0 loo< 1983 Smallmouth Bass F 27 9 434 0.083

1983 Smallmouth Bass F 25 4 317 0.035 0.036 0.073

198:3 Smallmouth Bass F 25 4 272 o.Wo< 0.000 0.130

1981 Smallmouth Bass F 22 9 113 0.026 0.026 0 140

198:3 Smallmouth Bass F 20 3 181 0.097 0.100< ~ ~ ~ ~

198:3 Rock Bass F 0.000 O.lOO<

198:3 Rock Bass F 0.020< 0.000 OIOOc

198:3 Rock Bass F 0.020c 0.000 O.lOO<

198:3 Rock Bass F

1983 Brown Bullhead F

198:3 Brown Bullhead F 0.020< 0.000 0.lOOC

1983 Brown Bullhead F 0.020C ~- 198:3 Common Sh~ner W 0.066 0.066 0.100<

198:3 Common Sh~ner W 0.066 0.066 0.1 00<

1983 Common Sh~ner W 0.066 0.066 0.100<

1983 Common Shner W 0.066 0.066 0.100<

1983 Common Shlner W 0.066 0.066 0.100<

198:3 Common Sh~ner W 0.066 0.066 O.lOO<

198:3 Common Shlnei W 0.066 0.066 0.100<

1983 Cornmon Shiner W 0.066 0.066 0.100<

1983 Common Sh~ner W 0.066 0.066 0.100<

Page 1 d \ ~ e l s ~ c ~ l \ d o c ~ \ S s h X I S

.. .. .. .

Grat~ot C o below St Lous Dam Brown Bullhead

Gratjot Co below St Lous Dani

Gratiot Co, below Sf Loills Dam Wh~te Sucker

Gratlot C o below St LOUIS Dam

Gratiot Co below St Louls Dam

Graf~ot Co below St Lou6 Dam

Gratiot Co below Sf Louls Dam

Gratot Co below St Louis Dam

St LOUIS Pine R~ver Imp

St LOUIS, Pine R~ver Imp 1989 Largemouth Bass F

St Lo i l~s, Plne Rlver Imp 1989 Largemouth Bass F

St Lout Plne Rlver Imp 1989 Largemouth Bass F

St LOUIS P ~ n e Rlver Imp 1989 Largemouth Bass F

St LOUIS. Pine R~ver Imp 1989 Largemouth Bass F

St Louis. Plne R~ver Imp 1989 Largemouth Bass F

St LOUIS. Pine R~ver Imp 1989 Largernouth Bass F

St LOUIS P ~ n e R~ver Imp 1989 Largemouth Bass F

St LOUIS P n e Rlver Imp

St Louts, P ~ n e R~ver Imp

St Lous, P ~ n e River Imp

St LOUIS, P~ne R~ver Imp

St Lous, Pfne Rfver Imp

St LOUIS, Ptne Rlver Imp

St Lous P n e River Imp

St LOUIS Pine River Imp

St LOUIS Plne Rlver Imp

Paae 2 d \vels~col\docs\Summfsl~ X I S

~ : O C A T I O N I DATE SPECIES STYPE LENGTIH WEIGHT FAT DDECONC DDDCONC DDTCONC TOTALDDT PBBCONC~

. ~~ ~~

St Lo111s Pin? R~ver Imp

St Lo~ris. Pine Rver Imp

St L o ~ ~ l s , Pine Rivet Imp

St Lous PI.>,? Rver Imp

St Lou s Pine River lnip

St Loo s Pine R~ver Imp

St Lou s P ~ n e R~ver Imp

St Lou s Pine R~ver Imp

St Lou s P ~ n e R~ver Imp

St Lous Ptne River lrnp

-- ~ ~ .~ ~ ~

(ems) (gms) (percent) (ppm) ~ ~ -~ -~~-~---~-p~ ~~

(PW) ( P P ~ ) ( P P ~ ) ( P P ~ ) 19t19 Black Crapp~e F 28 5 440 1 3 1.055 5.01 1 0.206 6.272 0.087

~ .... . Carp

Carp

Carp

Carp

Carp

Carp

Carp

Carp

Carp

St L o u i P~nc? R~ver lrnp I 19E9 Carp Fs 50 1810 6 65 5.614 11.745 3.667 21.026 0 111 -

199A .~

belox St Lous Dam

belov~, St LOUIS Dam

belovi St Loills Dam

below St Loufs Dam

below St Lnus Dam

belom, St L8,u$s Dam

below St Louis Dam

beom, St Lous Dam

belovg St Louis Dam

beovi St Louis Dam

below St Luus Dam

I 8 4 Carp Fs 56 2410 1 1 5 0.932 2.09CI 0.113 3.135 0.005< 1994 Carp Fs 48 1820 13 1 9.97 30.810 0.874 41.664 0.005~ 19E84 Carp Fs 52 2030 3 3.44 7.630 0.502 11.572 0.005~ 1954 Carp Fs 47 1500 11 3 12.58 31.620 3.106 47.308 0.005~ 1994 Carp Fs 47 1460 4 05 7.88 16.540 1.309 26.729 0.00% 1994 Carp Fs 54 2480 1 7 1.73 3.870 0.209 5.609 0.005~ 1994 Carp Fs 57 2320 0 6 0.706 0.861 0.081 1.648 0.005< 1994 Carp FS 54 2070 3 1 4.57 10.110 1.159 15.839 0.005< 195'4 Carp Fs 53 2200 9 7 13.95 25.340 3.389 42.679 0.00% 195'4 Carp Fs 50 1720 7 55 11.38 22.920 3.32 37.620 0.00% .. ... ...... .... . .. .. . . . .- .. .. , ..,. ,. - .. . 19F84 Carp W 46 1050 12 5 20.2 32.100 0.753 53.053 0.005<

below St Lollis Dam .- 1994 Carp W 61 3230 5 25 5.97 13.570 0.297 19.637 0.005~

1995

St Lous Impoundment Black Crapp~e f 29 5 390 0 25 0.786 2.330 0.222 3.338 0.667 St Lous Impoundment Black Crappie f 30 430 0 75 1.24 4.540 0.224 6.004 0.773 St Lous lmpr~~lndment Black Crapp~e f 30 460 1 1 5 1.5 4.430 0.260 6.210 0.570 St Louis Impoundment Black Crapp~e f 30 500 1 9 2.31 8.480 0.447 11.237 1.050 St LOLIIS Impoundment Black Crappe f 30 450 1 7 4.26 10.330 0.749 15.339 0.966 St 1.or11s Impoundment Black Crapp~e f 30 5 550 1 55 1.45 3.540 0.265 5.255 0.260 St L o i ~ s lmpciurrdment 1925 Black Crappie f 30 5 440 0 8 1.37 7.380 0.416 9.176 0.698 St Lo~i ls Impoundment 1955 Black Crapp~e f 30 5 520 2 4 3.34 11.130 0.594 15.064 1.450 St Lo1115 Impoundment 1955 Black Crapp~e f 31 580 1 1 5 4.46 4.710 0.340 6.610 0.651 St l o t i ~ s lrnpoun,iment 19'5 Black Crappie f 31 5 610 1 7

St L o l l s lmpriundment 19% Carp Fs 44 1240 0 6

Page ' d \velsco\docs~' fish xs

D~~~ 4 d \velsicol\docslSummflsh xls

LOCATION

~ ~ ~~~ ~ ~ ~ ~

St LOUIS Impoundment

St LOUIS Impoundment

St Lous Impoundment

St Louis Impoundment

St Lous Impoundment

St Lous Impoundment

St Lous Impoundment

St LOUIS Impoundmerit

St LOLIIS Impoundment

1997

Below St Louis Imp

Below St LOUIS Imp

Below St LOUIS Imp

Below St LOUIS Imp

Below St LOUIS Imp

Below St. Louis Imp

Below St Louis Imp

Below St LOUIS Imp

Below St LOUIS Imp

Below St LOLIIS Imp

Below St Louis Imp

Below St Louis Imp.

Below St Louis Imp

Below St LOUIS Imp

Below St LOUIS Imp

Below St LOUIS Imp.

Below St LOUIS lrnp

Below St LOUIS Imp

Below St Louis Imp

Below St LOUIS Imp

St LOUIS Impoundment

St LOLIIS linpoundrnent

St LOUIS Impoundment

St LOUIS Impoundment

St Louts Impoundment

St Louis Impoundment

DATE SPECIES STYPE LENGTH WEIGHT FAT DDECONC DDDCONC DDTCONC TOTALDDT PBBCONC

(ems) (gms) ~~~ (percent) ( P P ~ ) ( P W ) ( P P ~ ) ( P P ~ ) ( P P ~ ) 1995 Carp Fs 41.1 920 2 45 1.56 1.200 0.214 2.974

1995 Carp Fs 47 1480 2 55 3.15 6.250 0.322 9.722

1995 Carp Fs 44 1140 2 05 6.63 31.100 1.984 39.714

1995 Carp Fs 42 1000 1 05 6.34 34.800 1.03 42.170 1995 Carp Fs 48 1380 4 1 0.364 0.170 0.021 0.555 1995 Carp Fs 42 5 1200 3 1 11.91 28.200 3.158 43.268

1995 Carp Fs 47 5 1590 1 9 0.328 0.1M 0.014 0.506 1995 Carp Fs 64 3580 0 75 2.24 0.882 0.079 3.201 1995 Carp Fs 66.5 4360 2 4 13.74 0.372 0.032 14.144

10116197 Carp Fs 66 4680 4 9 3.327 13.964 0.651 17.942 0.005 1011 6197 Carp Fs 61 2 3180 5 2 2.056 8.151 0.406 10.613 0.005 1 011 6197 Carp Fs 58.4 2710 6.2 6.684 19.734 1.17 27.688 0.005 1011 6197 Carp Fs 58 2660 5.45 6.926 18.039 1.19 26.155 0.005 10116197 Carp Fs 53.2 2520 9 2 8.004 26.25 f.666 35.920 0.005 1 011 6197 Carp Fs 54.6 2500 5 55 8.45 16.927 0.905 26.282 0.005 10116197 Carp Fs 53.3 2460 3 4 1.842 9.22 0.682 11.744 0.005 10116197 Carp Fs 53.6 2450 18 5 14.943 53.146 4.47 72.569 0.005 10116197 Carp Fs 54.8 2240 5 9 6.361 19.03 1.074 26.465 0.005 10116197 Carp Fs 51.3 1970 8 8 8.111 34.535 1.223 43.869 0.005 10116197 Carp Fs 63.3 3640 2.45 2.387 8.73 0.451 11.668 0.005 10116197 Carp Fs 58.8 2820 3 15 2.605 10116197 Carp W 51.5 1960 11.8 12.754 39.199 10116197 Carp W 50.5 1760 12 6 12.037 38.532 2.394 10/76/97 Carp W 49.6 1780 16 6 16.285 1 011 6197 Carp W 48.7 1750 12 7 14.066 37.865 2.267 1 011 6197 Carp W 47.5 1740 13 3 17.653 42.224 10116197 Carp W 48.8 1870 18 16.814 58.907 10116197 Carp W 47 1 1620 9 9 8.704 10116i97 Carp W 46.6 7500 16 7 16.737 .. .. ... 10117197 Smallmouth Bass F 37.5 940 1 5 1.626 10117197 Smallmouth Bass F 34 5 725 1 9 5 1.216 10117197 Smallmouth Bass F 29 485 1 6 1.006 10117197 Smallmouth Bass F 27.3 385 2 05 1.543 10117197 Smallmouth Bass F 27.2 310 1 5 0.948 10117197 Smallmouth Bass F 28 1 390 1 85 0.94

-.OCATION I DATE SPECIES STYPE LENGTH WEIGHT FAT DDECONC DDDCONC DDTCONC TOTALDDT PBBCONC~

.. -~ ~~ ( cms l (gms) (percent) (ppm) (PPm) (Ppm) ( P P ~ ) ( P P ~ ) St Louts l m p o u n d m ~ ~ ~ b l l 7/97 Smallmouth Bass F 27.3 360 1.75 ' 1 .22 8.357 1.023 10.600 0.094

STYPE (Sample Type)= F: Sk in -on Fillet. Fs: Skin-off Fil let, W: Who le

St Louis Impoundment

St L C ~ U ~ S Irnpoundment

St L r ,u~s lmpoilnornent

St Lcuis lmpoutldment

St Lcu~s Impoundment

St LCJIS Impoundment

St L'JJ~S lmpou~idment

St L ~ ~ I I ~ s Impoundment

St L o i ~ s Impoundment

St LOOIS Impoundment

St L#,uls Inipoundment

St Ls>us Impoundment

St LOIJIS lmpouridment

St LOIJIS lmpouridment

St LOLJIS Impoundment

St LVIJIS Impoundment

St Louis lmpouridment

St Lou~s lmpouridment

St Lo~ils Impoundment

St LOUIS Impoundment

St Louts lrnpouridment

St Lous Impoundment

d \vels~col\docs\c ish x is

10117197 Smallmouth Bass F 25 2 260 1.35 1.134 7.259 0.887 9.280 0.107 10117197 Smallmouth Bass F 25.2 260 145 1.24 5.802 1.506 8.648 0.8 1011 7197 Smallmouth Bass F 25 240 125 1.049 7.316 1011 7197 Smallmouth Bass W 24.6 220 3 8 5.271 39.183 . - -- - 1011 7/97 Carp FS 78 5950 1.1 2.747 1.394 0.131 4.272 0.005 1011 7197 Carp Fs 76 5595 10.4 &685 3.841 1.371 6.897 0.055 1017 i197 Carp Fs 60 2880 1 8 2.814 7.662 0.428 10.904 0.005 10117197 Carp Fs 55 2320 1.7 4,328 12.337 1.379 18.044 0.005 1011 7197 Carp Fs 54 1910 2.9 17.812 60.232 11.871 89.916 0.005 10117191 Carp FS 54 2300 3.2 21.505 30.309 6.274 68.088 0.005 10117197 Carp Fs 51 1940 2.9 18.293 57.399 11.28 86.972 0.005 10117197 Carp Fs 53 1900 1.2 1.132 1.217 0.116 2.466 0.005 - ~

10/17/97 Carp W 52 1725 4 4 11.074 11.148 1.808 24.030 0.005 10117197 Carp W 52 1850 3.6 ,20.444 126.43 14.425 161.299 0.005 1011 7197 Carp W 52 1720 3.1 4.741 8.349 1.608 14.698 0.005 10117197 Carp W 48 1540 11.4 6.964 18.996 2.52 28.480 0.005 1011!197 Carp W 52 1760 10.8 29.645 46.479 11.104 87.228 0.005 1011?197 Carp W 48 1570 3.8 22.654 30.979 10.668 64.301 0.005 1011?197 Carp W 48 1350 4.2 9.893 23.651 2.942 36.486 0.005 1011 :?I97 Carp W 44 1400 8.7 8.79 7.629 0.516 16.936 0.005 1011 ;?I97 Carp W 46 1210 6.1 13.315 16.928 1.413 31 366 0.005 10117197 Carp W 43 1300 5.6 8.172 21.356 2.295 31.823 0.005

APPENDIX B

Alternative 1

COST ANALYSIS FOR NO ACTION ALTERNATIVE 1 - NO ACTION

VELSICOL ST. LOUIS. MICHIGAN

L~lng-term monitorin~ cast (30-years '4 8% rate)

Item description Present worth

180,125 180,125

i:lsh studies 2 ( ~ e a r I ~ , 0 0 0 ] I 'l'otal moriltorii,g cost

Frequency

$1 h.ilOi1 $lh,000

Factor CostiYear Unit CostNnit

COSI hN:\l.YSIS FOR SEDIMENT REMOVAI. ..\(l'lON A1.I'ERNATIVF. ,\I.rERNAI'IVE 2A: HYDRAULIC DREDGIIYG. DEWATERING.

AND WATER TREATMENT

VELSICOL ST. LOUIS, M1C;HIGAFl

$ 3 5 (1s t X hours)

$75 (2nd 4 hours) I $126,01

('OST ANAI.YSIS FOR SEDIMENT REMOVAL ,%('TION AI.TERVA'IIVE AL.TERNATIVE 2A: IfYDRAllLlC DREDGING. DEWA'I'ERING.

AND WATER TREATMENT VEL.SICOL

('OS'I ANA1,YSIS FOR SEDIMENI REMOVAL ACTION ALTERNATIVE :\LTERNATIVE 2A: HYDRAULIC DREDGING, DEWATERING,

AXD WATER TREATMENT VELSICOL

( ' O W ANALYSIS FOR SEDIMENT REMOV.4L A('I' l0N :\I. I FRNA rIVE ALrERNATlVE 3A: MECHANICAL DREDGING. I)EW,il'I.'RIN(;, AND

WATER TREATMENT VELSICOL

ST. LO1JIS. MICHIGAN

COST ANALYSIS FOR SEDIMENT REMOVAL ACTION AL'IERNATIVE AL'TERNA'IIVE 3A: MECHANICAL DREDGING. DEWATERING. ,\ND

WATER TREATMENT VELSICOL

ST. LOUIS. MICHIGAN

COST ANALYSIS FOR SEDIMENT REMOVAL ACTION A1,TERNATIVE ALTERNATIVE 3A: MECHANICAL DREDGING. DEWATERING. AND

WATER TREATMENT VELSlCOL

ST. LOUIS. MICHIGAN

& ;I = I;actor represents adjustments ibr ditliculty, s u e , and other intangibles !hat will affect the work

h = I)uc la round~ng, Lhc amount in thc Cust colulnn may be slighlly d~ffcrcnt Ltiun thc pioiluct ol.the values in thc qu;mtity, CostilJnlt, and Factor columns.

COST ANALYSIS FOR SEDIMENT REMOVAI. ACTION AL.TERNATIVE ALTERNATIVE 4: HYDRAULIC MODIFICATION OF PINE 'RIVER. EXCAVATION. DEWATERING.

AND WATER TREATMENT VELSICOL

ST. LOUIS. MICH1GA.N

COST ANALYSIS FOR SEDIMENT REMOVAL ACTION ALTERNATIVE ALTERNATIVE 4: HYDRAULIC MODIFICATION OF PINE RIVER. EXCAVATION. DEWATERING.

AND WATER TREATMENT VELSICOL

ST. LOUIS, MICHIGAN

COST ANALYSIS FOR SEDIMENT REMOVAI, ACTION ALTERNATIVE ALTERNATIVE 4 : HYDRAIII.IC MODIFICATION OF PINE RIVER, EXCAVATION. DEWATERING,

AND WATER TREATMENT VELSlCOL

ST. LOUIS, MICHIGAN

@

;I == IFactor represents adjostn~cnts 1Ur dilticuiti. sl,.e, illld olhcr in t i i~~p~hles lhi!t ililll affect the uork.

b - I)oe to roondlng, the amount in the Cost cuiolon inav he slightly difircnt than the product of the values

In the Quant~ty. CosUiJnit. uld Factor columns

COST ANALYSIS FOR SEDIMENT REMOVAL ACTION ALTERNATIVE ALTERNATIVE 5: DISPOSAL AT A RCRA SUBTITLE D LANDFILL

VELSICOL ST. LOUIS. MICHIGAN

Alternative 6

COST ANALYSIS FOR SEDIMENT REMOVAL ACTION ALTERNATNE ALTERNATNE 6: DISPOSAL AT A RCRA SUBTITLE C LANDFILL

VELSICOL ST. LOUIS, MICHIGAN

Item description I Quantity I Unit I CosUUnit IFactorl Cost

Cadtal cork: Direct capital cost Waste disposal at a commercial RCRA Subtitle C landfill

Disposal as nonhazardous uastc

Nan-hazardous waste transportation

Subtotal direct capital cost $16,087.50 - Markup for subcontract ( 8 5%) $1,367,43

'Total d~rect capital cost $17,454,938

178,7511

178,750

'Sons

Tons

$15500 $1 1,618.75

$2500

COST ANALYSIS FOR SEDIMENT CONTAINMENT ALTERNATIVE 7: IN SlTU SEDIMENT CAPPING

VELSICOL ST. LOUIS, MICHIGAN

days, 1-12 hr, shiwday on site+ 15%

Alternali\e 7

COST ANALYSIS FOR SEDIMENT CONTAlNMENr ALTERNATIVE 7: IN SlTU SEDIMENT CAPPING

VELSICOL ST. LOUIS. MICHIGAN

COST ANALYSIS FOR SEDIMENT CONTAINMENT ALTERNATIVE 7: IN SITU SEDIMENT CAPPING

VELSICOL ST. LOUIS, MICHIGAN

Key: a = I:actor represents adli~stments lor ditliculty, sue , and othcr untanglhles that will ;~ffect thc work.

h = I)uc to rounding, the curnoun1 in thc Cost column may he slightly d~tferent than the product of the valucs 111

lhc Quanluty, CoslAJnut. and ].:!ctor colutnuus.