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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)
-
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.
-
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.
-
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
-
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.
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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.
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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.