United States
Environmental Protection
Agency
Office 01
Emergency and
Remedial Response
PB93-964107
EPAIROD/R05-92/201
June 1992
SEPA
Superfund
Record of Decision:
Electrovoice, MI
Ru . ~. Environmen"tal Protection Agency
eglO~ III Hazardous Waste
Tecl1nrcallnformation Center
84: 1 Chestnut Street, 9th Floor
Philadelphia, PA 19107
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----
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EPA Report Collection
Information Resource Center
US EPA Region 3
Philadelphia. PA 19107
HozardoUS waste COltecftdn
information Resource Center
US EPA Region 3
Philadelph\a" PA 191Q1
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NOTICE
The aPPendices listed in the index that are not found in this document havE! been removed at the request of
the issuing agency. They contain material which supplement, but adds no further applicable information to
the content of the .document. All supplemental material is, however, contained in the administrative record
for this site.
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50272.101
REPORT DOCUMENTATION I 1. REPORT NO. I ~ 3. Recipient's Acceaaion No.
PAGE EPA/ROD/R05-92/201
4. ThIa and Subtitle 5. Report Date
SUPERFUND RECORD OF DECISION 06/23/92
Electrovoice, MI
6.
First Remedial Action - Final
7. Author(s) 8. Perfonnlng Organization RepI. No'
8. Parfonnlng Orgalnlzallon Name and Adchu 10. ProjactlTuklWork Unit No.
11. Contract(C) or Grant(G) No.
(C)
(G)
1~ ~ng Organization Name and AddreM 13. Type of Report & Period Coverad
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
Washington, D.C. 20460 14.
15. SuppI8nwUJy NoIM
PB93-964107
16. AbaIr8ct (UnlIt: 200 _Ida)
The Electrovoice (EV) site is an active manufacturing facility for audio equipment in
Buchanan, Michigan. Land use in the area is predominantly residential. McCoy Creek,
the nearest surface waterbody, is located approximately 2,000 feet north of the
facility. All residents are connected to the city water supply and city wells are
located 4,000 feet west of the property. Electrovoice has been in operation at its
present location since 1946. Current activities at the facility include painting,
electroplating, assembly, die casting, and machining. The site contains a dry well
area, where disposal of paint wastes occurred between 1964 to 1973; a fuel tank area,
which stored no.6 fuel oil from 1946 to 1960; and a lagoon area, where disposal of
electroplating wastewaters occurred from 1952 to 1962. In 1979, the state was
notified of a release of plating waste into one of the lagoons, which prompted an
inspection of the site. That same year, Electrovoice hired a contractor to remediate
the two lagoons and install ground water monitoring wells onsite. In 1980, the north
lagoon and its contents were removed, and the south lagoon was backfilled. However,
no contaminated materials were removed from the south lagoon. Ground water monitoring
conducted in 1980 revealed significant concentrations of VOCs and metals. The dry
(See Attached Page)
17. 00curn8nt Analyala L De8criptoI8
Record of Decision - Electrovoice, MI
First Remedial Action - Final
Contaminated Media: soil, sludge, gw
Key Contaminants: VOCs (benzene, toluene, PCE, TCE, xylenes), organics (P AHs ), metals
( chromi urn)
b. 1denIIfier8I00000Ended Terma
c. COSATI FieIcIIGroup
18. Availability SUIement 19. Security Class (This Report) 21. No. of Pages
None 52
I 20. Security Class (1bia Page) 22. Price
None
(See ANSl-Z38.18)
See IMl1uCIioM on Re-
OP1l0NAL FORM 272 (4-77)
(Formelly NTls.35)
Depu1ment o' Comrwce
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EPA/ROD/ROS-92/201
Electrovoice, MI
First Remedial Action - Final
Abstract (Continued)
well ,area soils are the principal onsite threat because they are the source of the ground
water contamination. This ROD addresses remediation of onsite ground water and soil as a
final remedial action. ~ future ROD will address all offsite ground water contamination,
which extends from the EV property boundary about one-half mile north to McCoy Creek.
The primary contaminants of concern affecting the soil, sludge, and onsite ground water
at the site are VOCs, including benzene, PCE, TCE, toluene, xylenes; other organics,
including PAHs; and metals, including chromium.
The selected remedial action for this operable unit includes construction of a soil vapor
extraction system (SVE), followed by excavation of 2,100 cubic yards of remaining sludge,
offsite solidification, and landfilling of the sludge layer; collection and treatment of
onsite contaminated ground water onsite using either granular or powdered activated
carbon, air stripping, chemical oxidation/reduction or photolysis/oxidation; discharge to
a POTW; and monitoring of off-property ground water. If, following these actions, the
soils do not meet treatment standards, further remedial action consistent with RCRA
closure will be taken, including installation of a hazardous waste cap over the lagoon
area soils. An investigation of the potential existence of a lower aquifer in the area
of the former dry well area will also be conducted. Deed restrictions for the property
and surrounding properties will prohibit future installation of drinking water wells.
The estimated present worth cost for this remedial action is $4,100,000, which includes
an annual O&M cost of $330,000 for a 2- to 5-year operational period.
PERFORMANCE STANDARDS OR GOALS: Chemical-specific soil clean-up goals are based on state
standards and include arsenic 0.4 ug/kg; benzene 20.0 ug/kg; PCE 14.0 ug/kg; TCE
60.0 ug/kg; toluene 16,000 ug/kg; and xylenes 6,000 ug/kg. Chemical-specific ground
water clean-up goals are also based on state standards and include benzene 1.0 ug/l; TCE
3.00 ug/l; toluene 800.0 ug/l; xylenes 20.00 ug/l.
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DECLARA~ION FOR THE RECORD OF DECISION
SITE NAME AND LOCATION
Electro-Voice Site
Buchanan, Michigan
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for
. the Electro-Voice, Inc. (EV), site developed in accordance with
the Comprehensive Environmental Response, Compensation, and
'Liability Act of 1980 (CERCLA), as amended by the Superfund
Amendments and ReaUthorization Act of 1986 (SARA), and, to the
extent practicable, the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP).
This decision is based upon the contents of the Administrative
Record for the EV site.
The State of Michigan concurs on the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this
site, if not addressed by implementing the response action
selected in this Record of Decision (ROD), may present a current
or potential threat to public health, welfare, or the
environment.
DESCRIPTION OF SELECTED REMEDY
This operable unit is the first of two operable units for the
site. The first operable unit addresses remediation of on-
property groundwater and soil contamination by eliminating or
reducinq the risks posed by the site throuqh treatment of the
source of groundwater contamination, the dry well area soils,
treatment of on-property groundwater, monitoring off-property
qroundwater, and engineerinq and institutional controls.
The major components of the selected remedy include:
*
Evaluate and determine the existence of a separate
lower aquifer and any impact the EV site may have on
it.
Deed restrictions on the EV property to prohibit
installation of drinking water wells and prohibit
construction in the lagoon area and dry well area if
cleanup levels are not attained. Deed restrictions on
properties under which the EV.plume travels to. prohibit
installation of drinkinq water wells.
*
1
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DECLARATION
*
Soil Vapor Extraction (SVE) for 2 to 5 years followed
by excavation, solidification and landfilling of the
dry well area sludge layer.
If after treatment and excavation the dry well area
soils do not meet the cleanup standards established
pursuant to Michigan's Act 307 Type B criteria, u.s.
EPA will consider further remedial action consistent
with RCRA.
*
*
Install and maintain a hazardous waste cap meeting the
substantive requirements of Michigan's Act 64 over the
lagoon area soils. .
*
Install and maintain a groundwater collection and
treatment system capable of capturing all contaminated
groundwater located beneath the EV property boundary.
Groundwater will be actively remediated until it meets
Michigan's Act 307 Type B cleanup standards.
Discharge of treated groundwater will be to the
Publicly Owned Treatment Works (POTW).
*
*
Monitor off-property groundwater.
The selected remedy for the first operable unit is protective of
human health and the environment, complies with Federal and state
requirements that are legally applicable or relevant and
appropriate to the remedial action, and is cost-effective. This
action utilizes permanent solutions and alternative treatment
technologies to the maximum extent practicable given the limited
scope of the action. Because this action does not constitute the
final remedy for the site, the statutory preference for remedies
that employ treatment that reduces toxicity, mobility, or volume
as a principal element will be addressed at the time of the final
response action. Subsequent actions are planned to address fully
the off-property groundwater at this site.
Mil. tt&/
A Valdas v. Adamkus
Regional Administrator
u.s. EPA - Region V
~/(£ 23 Ifflr
Da e "/
2
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RECORD OF DECISION
DECISION SUMMARY
ELECTRO-VOICE SITE
SOURCE CONTROL OPERABLE UNIT
BUCHANAN, XICHIGAN
Prepare4 :By:
U.8. Environmental Protection Aqency
ReqioD V
chicaqo, Illinois
June, 1992
3
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TABLE OF CONTENTS
I.
Site Location and
Description..............."........... .6
II.
Site History and Enforcement Activities ......... .......7
III. Community Relations Activities
. . . . . . . . . . . . . . . . . . . . . . . . 8
IV.
Scope and
Role of the Action................ ..... . .... .10
V.
Summary of Site
Summary of Site
Characteristics....................... .11
.VI.
Risks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
A. Contaminants of Concern............................ .12
8 . Toxicity Assessment......................... . . . . . . . . 12
C. Exposure Assessment and Risk Characterization...... .13
D. Ecological Assessment............:................. .16
VII. Environmental Standards Not Met at the Site........... .17
A . Groundwater......................................... 17
Groundwater Protection Goals and the NCP......... .19
State of Michigan Groundwater Protection Goals....19
Cleanup Standards................................. 20
B. Dry Well Area Soils............ ~ . . . . . . . . . . . . . . . . . . . .22
C. Laqoon Area Soils........... ~ . . . . . . . . . . . . . . . . . . . . . . .23
D. Rationale for Further Action....................... .23
VIII.Summa~y of Alternatives.............................. ..24
IX.
Comparative Analysis of Alternatives...................30
x.
Selected Remedy.......................... ~ . . . . . . . . . . . . .34
A. Remediation Standards................................ 35
XI.
Statutory Determinations...............................35
A. Protection of Human Health and the Environment......36
B. Compliance with ARARs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
C. Cost-Effectiveness................................. .41
D. Utilization of Permanent Solutions and
Alternative Treatment Technologies (or
Resource Recovery Technologies) to the
Maximum Extent Practicable..........................41
E. Preference for Treatment as a Principal Element.....42
XII. Documentation of Significant Changes...................42
XIII.Responsiveness Summary..................following page 44
4
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FIGURES AND TABLES
Fiqures
Followinq Paqe...
1
EVProperty Map
6
2
Site Map
6
Tables
.1 Chemicals Detected in Groundwater
2 Chemicals Detected in Soils
3 Summary of Chemicals of Potential Concern
.10
11
12
Paqe Number
4 Groundwater Standards and Cleanup Criteria 18
5 Groundwater Remediation Standards 21
6 Dry Well Area Soils Remediation Standards 22
5
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1.
SITE LOCATION AND DESCRIPTION
Electro-Voice, Inc. ("EV"), is located at 600 cecil Street in the
City of Buchanan, Berrien County, Michigan, and is a manufacturer
of audio equipment. Current activities at the facility include
painting, electroplating, assembly, die casting and machining.
EV has been in operation at its present location since 1946.
The site consists of the Electro-Voice building and parking area,
a former dry well area where disposal of paint wastes occurred, a
former lagoon area where disposal of electroplating wastewaters
occurred, a former fuel tank area and a groundwater contaminant
'plume which extends from the EV property boundary one-half mile
north to McCoy Creek. Groundwater contamination has been
determined to extend from the Electro-Voice property to McCoy
Creek, which is located approximately one-half mile north of the
EV property (downgradient). See Figures 1 and 2.
The population of Buchanan in 1980 was approximately 5,142. The
EV property is surrounded on three sides by residential homes and
on the fourth side by an elementary school. All residents are
connected to the city water supply. The city wells are located
approximately 4,000 feet west of the EV property and are not
considered to be threatened by the EV contaminant plume, as
groundwater flow is to the north. The city water supply wells
are screened from 20 to 44 feet below grade and are screened in
the same aquifer in which the EV contaminant plume exists. The
city's water supply is tested annually for volatile organic
compounds (VOCs), and according to a city official, has never
tested positive for VOCs.
McCoy Creek is the nearest surface water body and is located
approximately 2,000 fee~ north of the EV facility. The Creek has
an average depth of 2 feet, average width of 12 feet, and average
velocity of 0.66 feet per second. McCoy Creek discharges into
the st. Joseph River. other surface water bodies in the vicinity
of the EV property consist of ponds associated with gravel-pit
operations, and several small unnamed lakes and ponds southeast
of the property.
There are no rare or endangered species known to be resident at
the EV site, nor are there species of special economic or
recreational value for which the EV site serves as critical
habitat. McCoy Creek is designated as a protected trout stream
by the Michigan Department of Natural Resources (nMDNR"). Brown
trout are stocked by MDNR at locations upstream from the City of
Buchanan. There are no known wetlands in the immediate vicinity
of the EV property. '
The study area is covered with soils of the Oshtemo series.
These soils are formed on glacial outwash plains and moraines and
are described as well-drained sandy loams. Permeability is
6
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EV Property
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SOURCE: Fqur8 ,... s.cn...- Fa
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FIGURE 1
EV PROPERTY MAP
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FIGURE 2
SITE MAP
Co............ ~ PII88
EIIcIa- ~ ~....... Inc. IS
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moderately rapid in the upper part of the subsoil and very rapid
in the lower part. The study area generally consists of two'
geological units: an outwash, sand and gravel unit, underlain by
a clay-rich-till unit. The upper portion of the outwash'unit is
unsaturated and the lower portion comprises an unconfined
aquifer. Drillers' logs of the region indicate that a lower-
confined aquifer also exists in localized areas. In the areas
where both aquifers exist, they are separated by a clay-rich-
confining layer.
II.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
In 1952, EV constructed two clay-lined lagoons (north and south)
for disposal of liquid waste from the electroplating operation at
the plant. The north lagoon was the primary discharge lagoon.
The north lagoon was approximately 50 feet in diameter and 11
feet deep with very steep side slopes. EV discharged plating
waste to the north lagoon from 1952 to 1962'. Information
supplied by plant personnel indicates that this lagoon was
continuously filled. with standing water. A 12-inch-diameter pipe
served as an overflow to the south lagoon. The south lagoon was
approximately 40 feet by 75 feet in area and 10 feet deep. Use
of these lagoons was discontinued in 1962, due to t~e
installation of a new wastewater treatment facility in the EV
building.
With the installation of a new automated painting system in 1964,
a dry well was installed for disposal of wastes produced during
painting operations. The dry well consisted of a hole in the
ground which was backfilled with gravel. A gravity drain pipe
connected a sink inside the building to the dry well. The sink
was used to clean equipment associated with the paint shop.
Liquid waste disposal in the sink reportedly included cleaning
solvents (toluene, xylene, 2-butanone (HEK) and chlorinated
solvents) and residual paint used in the manufacturing
operations. The dry well was reportedly in use from 1964 to
1973. .
In 1973, a subsurface tank (20,OOO-gallon capacity) was installed
immediately west of the dry well to collect discharge from the
paint shop. In 1975, the subsurface tank was removed and
replaced with an upright buried tank of similar capacity. The
second tank was removed in 1983. An aboveground tank, with a
capacity of 1,000 gallons, was placed near the dry well and was
identified as the HEK tank. The MEK tank has also been removed
from the site.
Two partially buried
from the site during
since 1930. EV used
No.6 fuel oil.
fuel-oil tanks were excavated and removed
July 1987. These tanks had been onsite
the tanks from 1946 to 1960 for storage of
7
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In March 1979, plating waste solution was released into the north
lagoon as a result of a ruptured drain pipe. EV reported this
incident to the MDNR, which began an investigation of the site
shortly after the incident was reported. The MDNR requested a
review of 'onsite plating waste treatment and conducted an
inspection of the EV property in March 1979.
In 1979, EV hired a contractor to develop a program for removal
and abandonment of the two lagoons. In January 1980, four
groundwater monitoring wells were installed around the lagoons to
determine if liquid waste had leaked from the lagoons, thereby
contaminating groundwater in the area. Groundwater samples
collected in January 1980 contained detectable concentrations of
xylene, toluene and lead.
In September 1980, the north lagoon and its contents were
removed. The area was then backfilled. The south lagoon was
merely backfilled (no contaminated materials were removed) and
leveled to the natural surface topography of the area.
On July 29, 1982, a Hazard Ranking System (HRS) score was
developed for the EV site. On September 8, 1983, the EV site was
proposed for inclusion on the National Priority List (NPL), and
the proposal became final on November 21, 1984 (49 Fed.Req. 185).
In October 1987, EV entered into an Administrative Order by
Consent to conduct the Remedial Investigation and Feasibility
Study at the EV site.
III. COMMUNITY RELATIONS ACTIVITIES
A Community Relations Plan for the EV site was finalized in March
1989. This document lists contacts and interested parties
throughout government and the local community.' It also
establishes communication pathways to ensure timely dissemination
of pertinent information. A fact sheet outlining the Remedial
Investigation (RI) sampling program was distributed to interested
parties in February 1991. U.S. EPA held a public meeting in
Buchanan, Michigan on February 28, 1991, to explain the results
of the RI. U.s. EPA was informed by the public at the public
meeting on February 28, 1991, that children were regularly
playing in the former lagoon area on the EV property. In
response to this information, u.s. EPA collected five surface
soil samples from the lagoon area soils. The samples were
analyzed for arsenic, lead and cadmium. The levels of cadmium in
the surface soils exceeded the recommended levels for residential
backyard soils. u.s. EPA requested that EV construct a fence
around these soils immediately to discourage children from
trespassing on them. EV complied with this request. U.s. EPA
held an availability session in Buchanan on May 14, 1991, to
discuss the lagoon area soil sampling results and any other
health concerns the public had.
8
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u.s. EPA and MDNR notified the local community, by way of the
Proposed Plan; of the recommendation of a remedial alternative
for the EV site. To encourage public participation in the
selection of a remedial alternative, u.s. EPA and MDNR scbeduled
a public comment period from October 1, 1991, to November 29,
1991. At the request of the Buchanan City Manager, the public
comment period was extended to December 13, 1991.
u.s. EPA and MDNR held two public meetings in Buchanan, Michigan,
on October 30, 1991, and November 14, 1991, to discuss the
recommended remedial alternatives and the other alternatives
identified and evaluated in the Feasibility study (FS).
Transcripts of these meetings are included as part of the
Administrative Record for the EV site.
A significant change has been made in the remedy selected for the
EV site since the publication of the FS and the Proposed Plan in
september 1991. The remedy recommended in the Proposed Plan was
Alternative 4A: institutional controls; soil vapor extraction of
dry well area soils followed by excavation and landfilling of
remaining sludge layer; Michigan's Act 64 cap on the lagoon area
soils; pump and treat all on- and off-property contaminated
groundwater. Since publishing the Proposed Plan, U..S. EPA has
determined that an operable unit. approach is more appropriate for
this site than selection of a final remedy at this time. The
Agency's decision to utilize an operable unit approach was made
after considering the substantial number of public comments which
preferred m~nitoring the off-property groundwater rather than
actively remediating the off-property groundwater through pump
and treat. u.s. EPA has determined that the operable unit
approach is more appropriate at this time because it allows a
more focused, logical approach, whereby the contaminated soils,
which are the source of groundwater contamination, and the more
highly contaminated groundwater, the on-property groundwater, are
treated first. The treatability study is requireq under this
first operable unit ROD. u.s. EPA will evaluate the effect of a
treatability study on soils and on-property groundwater prior to
making a final remedy decis~on for the off-property groundwater
in the second operable unit ROD.
u.s. EPA's responses to comments received during the public
meeting and to written comments received during the public
comment period are included in the Responsiveness Summary which
is attached to this ROD. This decision document presents the
selected remedial action for the first operable unit for the EV
site in Buchanan, Michigan, chosen in accordance with CERCLA, as
amended by SARA, and, to the extent practicable, the NCP. The
decision for this site is based on the Administrative Record.
AIl'comments which were received by u.S. EPA prior to the end of
the public comment period, including those expressed verbally at
the public meeting, are addressed in the Responsiveness Summary
9
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which is attached to this ROD.
IV.
SCOPE AND ROLE OF THE ACTION
This ROD addresses the first of two operable units for the EV
site and consists of treatment and excavation of the dry well
area soils, closure of the lagoon area soils, treatment of the
on-property groundwater and monitoring of the off-property
groundwater. The threats posed by this site to human health and
the environment are future residential use of contaminated
groundwater (both on- and off-property), and future residential
use of the lagoon area soils. The dry well area soils are the
principal threat at the site because they are the source of
groundwater contamination.
These threats will be addressed through the selected cleanup
action, which includes:
Lower Aquifer Investiqation
*
Determine whether a lower aquifer exists below the clay
till in the area of the dry well area soils, and ensure
that no contamination from the EV site has .entered the
lower aquifer, if it exists.
Drv Well Area Soils
*
*
soil vapor extraction
excavation, solidification and landfilling of sludge
layer
closure, if cleanup standards cannot be met with SVE
and excavation
*
Laqoon Area Soils
*
*
determination of the extent of contamination
capping of contaminated soils with a hazardous waste
cover pursuant to Michigan Act 64
Groundwater
*
pump and treat on-property groundwater with discharge
to a publicly-owned treatment works (POTW)
monitor off-property groundwater.
*
NOTE: The term "on-property groundwater" means all contaminated
groundwater located under the EV property: "off-property
groundwater" means the portion of the contaminated groundwater
plume which was identified during the Remedial Investigation,
extending from the EV property boundary approximately one-half
mile north to McCoy Creek (see Figure 2, site map).
10
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V.
SUMMARY OF SITE CHARACTERISTICS
The purpose of a Remedial Investigation (RI) at a Superfund site
is to characterize the nature and extent of contamination and
associated risks posed by hazardous substances at a site.. The
objective of an RI 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 the most
appropriate for a given site.
The RI performed at the EV site was designed to determine the
nature and extent of site contamination through a program of
. soil, groundwater and surface water sampling. site geology and
ground water flow patterns also were examined during the study.
Analysis of groundwater indicated the presence of eleven VOCs and
two inorganic compounds. Maximum contaminant Levels (MCLs),
established by the Federal Safe Drinking Water Act, were exceeded
in on-property groundwater for vinyl chloride, benzene,
ethylbenzene, and toluene. Off-property groundwater consists of
the groundwater contaminant plume which extends from the EV
property boundary, approximately 2,000 feet north to McCoy Creek.
Off-property groundwater exceeded MCLs for trichloroethylene and
vinyl chloride. contaminants detected in groundwater during the
RI are presented in Table 1.
Fuel tank area soils indicated five VOCs in concentrations
considered to be too low to pose a threat to human health and the
environment. .
Three out of five surface water samples from McCoy Creek showed
levels of 0.6 ug/l of trichlorethylene, which is below the
Michigan ambient water quality criteria (AWQC) of 94' ug/l.
The population within the study area is presently utilizing city
water for domestic uses. The City's groundwater wells are not
considered to be threatened by the EV plume, although they are
located in the same aquifer.
Analysis of dry well area soils indicated the presence of nine
VOCs, twenty-six semi-volatile compounds (SVOCs), and fifteen
inorganic compounds above background levels.
Analysis of north lagoon area soils indicated the presence of two
VOCs, five SVOCs, and thirteen inorganic compounds above
background levels. Analysis of south lagoon area soils indicated
the presence of three VOCs, ten SVOCs and seventeen inorganic
compounds above background levels.
contaminants detected in soils are presented in Table 2.
11
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TABLE 1
a...lcau DIn'8n8D I. O80......A7..
rw..u.'CT .f
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..... Llalh Conc..'nUon. Ln."
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"&aWl US
ac.t... 1/" IIA 10 - no I - ... I - II
1........- 1/11 I , I - ,. 10
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1.1.'a.....' 1/" I" II no - Itl "0
Carll.. '''ailid. 1/11 ." S - "I I NO
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Chi 810181. 1/11 ." I - 110 1-' NO
Chl.ro...It.n.- 1/11 I" .. - UI II NO
I,I-Dlchlor..'h...- 'III "" 5 I - III "0
1,I-Dlchl.r...It.... 1/11 I , - II' I - II 810
I,I-Dlcltl.r,,'h... 1/11 "" I - "I I NO
I,I-Dlcltl.r..",., 1'0..11- 11/.. I , I - III "0
Dlbro..chl.r...th... 5/11 81" 5 - 110 1 . I "0
It"lb....... ./.. 1 , I - I,'" 810
.-"...,I-I-'.n""o". 1/11 .' I' - nl n "0
"o'h,.... chlorld. 11,11 I' S - UI 1-' 1-'
"olu....' 1/11 I , I - 11,001 NO
I,I.I-.wlchlor..th.n.' I,.. 1 , - 50 1 - IS 10
.rlchl.ro.'I1...- 18,.. II 5 - UI I - 18 10
"rlc'lo...'II,....- 1/II .a ID .. liD
91.,. chl.rI... '/11 ' 10 - ..0 5 - 11 110
.,..... Itot.ll- 1/.. . S I - I,'" 810
laal-90LaTIUS
"0 1....lc acl.' 1/" ." 51-56 '" ND
o 1I1.11-.'h,lh..,II,"h.I...- 11,11 ." II-II 5 - II 10 - ..
00 1,4-DI...It,I,......' I'" ." II-II . ID
1-loth,l,h...I' 1/11 ." II-II II liD
;0,0 1-ldh,I,h...ol- I,ll I. II-II .. liD
-
C)O ...,tll...... I,.. "" II-II "I ND
-C flnus
Z»
~t:: 11..1... .,.. I JI-U n - St.S Ii - 69.'
I,"ao., I'll "I II - 51&1 II.' ND
~ ar...lc 1/11 . I.' - 1:1 I.' 1.1 - II
1,,1.. 1,.. . HI II - In II - ltJ
I ~",III..: II" NI I.n - '.1 1.1 0.11-1.'
I ca..lu8 I'" I . - ... II.' II.'
Calclu. J,II 11& III 5',100 - I",'" to ,100 - 1.010,000
'.u'.u;'..,~~,,~ .I~o' 11M.'.
-------
"0
0°
;;00
_:::0
Qo
zc
>)>
r- r-
~
Tabl~ 1 (C!ont - )
fuqu.ncy or
D.t.cU.n ..n" or
I..,a. "8n,. or
Qu..Uhtlon DIt.et.. .'C"l'ound
Abo.. LI.U, Cone.atl'.taon. L.....
ch..lc.1 OWlU" "CL ""/L' b,/L' .",/L'
Chl'OllUI a/.. . '.J - ... .., ..,
Cob.n II" HA I.a - I.' ..., - J.' J.J - U.,
COpp,1' 1/11 . I.' - 1.1 '0.1 - IS.S .... - U
II'0n It/.. 1 1.1 - I ... - n.101 11.1 - n,"1
LOI' 1/11 N" l.tI - L' 1.1 - '.1 J.'
""n..aul '/" "" "' n.Ja. - ".101 ",801 - sa."1
".n,..." a ./11 ' I' ".J - UI '.J - 511
"nc..y a/.. ' 1.11 1.1 liD
lIad.a II" . U - n.1 II ID
,ou..a.. 1/.. ... a.111 - 1,"1 ..ua - '."" ',111 - aa,ll'
1I1..lu. 1/" II. '.1 - II ID ID
III... 1/" "" 5.1 - ,.. ID ID
10.1.. '/" II. "' J,na - IU. 001 ., no - J6, 110
Tit. I IIUI 1/.. II. ... - I ID liD
...I.lu. 1/.. It. H' I.' - II.' ... - 15.'
line 1/.. I J.I 15.' - In II - ',110
IIIO.GUICS
c,..I'. II" "" a. It - 1,010 .. - 1.010
IENIEY".IIDI"', hiol. '"-21
Hi - Not 1.,lllb'l.
ND . lot ..tlctl'.
"CL . s.t. ..In.I., w.t.. .t .,.i..1 cont..ln.nt a.v.l.
.Ch.llc.a..ot pot,ntl.. c.nco.n.
Sou u:o :
Icol0tY .nd En.i.on..nt, Inc. ."0.
-------
TABLE 2
allllrc:u.l _.£_- D SOZU
..... .f
S....~. ..... 01
Qua~i~a~i.. D.ten... ..-.~....
rr....8CT d UUU c:o--c~.~a... Lo981.
Q8Mca~ D8~.cu.oa (".,.., C".,..' C""'9'
~
Ac:oC... nn5 11 - 24.0ao u - :1.100 ant
.......- 1/2S 5 - U.ooa 1.100 ant
2-"'.....- 3/25 10 - 24.oao 511- .. tOO ant
QJ.8r.'.ro 4.125 5 - 12.000 1 - ) 1 - 3
1.1-Dical.~..~.- 4'25 5 - 12.000 4 - no R
~.2-Dica1.r.8sa... .totall- 5.125 5 - 12.DOO 1 - 2 CICI I'ID
EUlVl.."."- I,Z5 5 - no 11 - ".ODa 1m
.-Ro~1-J-'..C""8 11'25 10 - 24 .000 4 ant
".tay1... cal.ca". U/2! M 4 - ..000 R
sqo~.- 1/U 5 - 12.000 , . COO ant
,..c~.~.r8.ca...- sns 5 - no 1 - 14. 000 lID
"01.... - .n5 5 - ..0 2 - 130.000 lID
1.1.1-tricb1.,"""'- 5/15 5 - 12.100 171 - 6 .ZOI lID
'!"icUo,..ca...- 11/15 5 - 12.101 2 - 420 lID
SF"'...' .t.~J- Ins 5 - , 4 - no .000. -
saar-w1Aft1.81
Ac"'''~- 11'11 3.. - 1.500 nl 8D
Ac....-uayl...- 11'15 3.0 - 1.501 120 lID
Mtar.c...- 11'15 3.. - 1.500 ZOO lID
'."...I&.ta~.".8- 11'15 ,.. - 1. 510 no lID
'.....k"lU8'''~...' 31'11 ,.. - 1.510 3t - 2.000 lID
'8"oC.,tlu.,..~.'" 31'15 3tO - 1.510 3t - 2.001 lID
'8...C.IPI'~..0- 11'15 3.. - 1. 510 nl n
......,...il..ry~8"- 11'15 ,.. - 1.500 nl lID
.8...ac &ea.- 1.111 1.100 - '7.301 '4 lID
...8T1 de...l- 11'15 3.. - 1.500 41 lID
~~..Z..~lb..Tll..caal.~.- . 1/15 3.. - 1.510 a .500 - u .000 lID
'u~l ..aoyl ,.~1.~.- 11'15 ,to - 1.510 121 8D
au..,..-- 2/11 3.. - 1.500 U - no -
D1.....'...'oaca,.....- 1.115 3.. - 1.500 150 8D
D1H...,.,..- 1115 34. - 1.510 ... lID
U---tyl ,1tdaa18c.- 1115 3.. - 1..11 150 lID
1.2-Di~.'''''''''. 1111 3.. - 1.511 I. 8D
z. .-Di-CIITlpoao~ - 1111 3.. - 1.511 5J. -
Di---'Yl ,.~....~. 1111 3.. - 1..0. 41. -
rl..ca.dt888- Sill 3.. - 1..11 .. - 1..0. .J!ID
u..,.- 1115 3.. - 1..11 '10 lID
%.....ll.2.J-c..PrT".- 111' J.' - 1..11 340 8D
2-11.~1""caa~.-- 4111 J.' - 1..11 " - 1.nO ID
2-11.caylp...l. 2115 '" - 1..11 II' - 640 ID
4-11.cayl,....I. 1115 '" - 1.511 U. . lID
.....U.l.... 4.111 ,.1 - 1.511 11.1'1 - 14.110 ID
,1a....U,."- S/1I ,.1 - 1..10 5e - 1..'0 ..
ry~...- 4/11 ,.0 - 1.'" 10 - 1.~00 lID
1.z..-rr1C1t1.~........ 1/11 ,.1 - 1.'" 11 ID
t&8ICVZ,aO:D2.11. 11lDI. Pft815
Pv,-" , ,.
ORIGjNAL
. -.... J
-------
Table 2
(cant. )
~o~ca!.
JII8DIo8
UU8&O-
,.&~..o,
A~..~c.
..w~_.
luyUi1l8
C&8III&-.
Calci-
caw....
CUU&
C..,.w.
U.
Le...
"a......
mo......
..oen"
Hi...1.
pot....-
Se1ou.
SU..oc
s....-
ftaUi1l8
'a..~-
Ii..
II ..~
ey88&U
lID . .ot dotoc&o..
SA . Not ...&1&810.
r~ocruoacy o~
CotOC1:&OD
11.111
4/11
11.111
11.111
1.111
1.111
11.111
11.111
11.111
11.111
11.111
11.111
11.111
11.111
1.111
10.111
'7/11
0/11
1111
11"11
2.111
11.111
11.111
5111
Souccor
.eaO"C..8 0' potoata.. c08COca.
Aaa..o of
5."'.0
Q\&..t&~aU,OD
~a&t.
(N9"k"
SA
7.0 - '.3
SA
SA
O.OU - 0.13
0.10 - 0.11
IUo
IUo
SA
IUo
SA
1IA
IUo
IUo
0.10 - 0.11
6.5 - 6.J
311 - ..6
o.tS - 4.5
1.1 - Z.C
1IA
o.SI - 0..'
SA
SA
0.11 - 0.17
te010", a.a ca..aeo....c. %ac. 1J.0.
~~:,:leo :a:!-
11....0 o~
O.tOCtoa
Coacoo1:..a1:&oa.
(1I,,,a,,
1.100 - 6.520
i.1 - 9.1
1.5 - 14
4.' - It
0.11 - 0.41
O.IS - 73'
UI - n.lOo
1.5 - 1.1"
2.2 - 5.2
'7.2 - 152
c.no - 15.100
c., - n
,n - Jt.IOO
::. - nl
0."
7.1 - 112
UJ - 1.%I~
lID
"
UI - 1.010
0.. - 0.42
5 - l'
31 - '"~
'7.5 - 24
8ack'l'ouaa
..0..1.
111"."
;: .110 - IoJOO
SO
2.0 - 4.'7
12-13
0.21 - 0.40
lID
531 - ..100
5.5 - t.4
2.1 - 6.1
11-15
6.UO - 12.700
5.4 - 15
n. - 1.060
11'-721
!tD
8.1 - 17
721
1m
lID
220 - 241
n
I.. - 10
40 - '7'7
IcaIEV2'OO:~Z'17. Il104. lReal
n
POOR QUALITY
ORIGINAL
-------
VI.
SUMMARY OF SITE RISKS
A baseline risk assessment (RA) was conducted for the EV site in
accordance with the guidance provided in U.S. EPA's Risk"
Assessment Guidance for SUDerfund (RAGs): Volume I. Human Health
Evaluation Manual and risk assessment guidelines developed by the
State of Michigan. The RA for the EV site is presented in two
documents entitled "Risk Assessment for the Electro-Voice Site,"
September 1990, and "Supplemental Risk Assessment for the
Electro-Voice Site," March 1991. The baseline RA consists of an
identification of chemicals of concern, toxicity assessment,
exposure assessment, risk characterization and ecological
. assessment. The baseline RA assumes no corrective action will
take place and that no site-use restrictions will be imposed.
The RA then determines actual or potential risks or toxic effects
that the chemical contaminants at the s~te pose under current and
future land use assumptions.
The off-property portion of the groundwater plume of
contamination moves for a half mile under residential and city
property before it discharges to McCoy Creek. Therefore,
exposures based on drinking and dermal absorption were used to
estimate the risks posed by the groundwater. The source of
hazardous substance contamination of the groundwater are the dry
well area soils at the EV property. The property owned by EV is
currently used for industrial purposes; however, the property is
bounded on the north, south and west by residences. The east
side is bounded by an elementary school. Therefore, exposures
based on reasonable future residential land use are appropriate
to estimate the risks posed by the source areas.
MCLs were exceeded in on-property groundwater for vinyl chloride,
benzene, ethylbenzene, and toluene. Off-property groundwater
exceeded MCLs for trichloroethylene and vinyl chloride.
A.
Contaminants of Concern
contaminants of concern are detected contaminants which have
inhere~t toxic/carcinogenic effects that are likely to pose the
greatest concern with respect to the protection of public health
and the environment. Selected contaminants of concern, for the
purpose of the RA at the EV site, are presented in Table 3.
B.
Toxicity Assessment
The purpose of the toxicity assessment is to develop human health
and environmental receptor toxicity and carcinogenicity data for
the chemicals of concern at the site and to provide an estimate
of the relationship between the extent of exposure to a
contaminant and the likelihood and/or severity of adverse
effects. The toxicity assessment is accomplished in two steps--
hazard identification and dose-response assessment.
12
-------
TABLE 3
SU111Q8Z 01' c::sagCloLa 01' Jov.;_...&L ......~
C:o.c..c~.cJ.O..
Oeuc..L
s.u.
(~II.'
G~._".c.~
("'.110'
..,........-
.......
Ol....ea...
Ol..._ea...
1.1-D1Cb1.~..C88..
1.~-D1Cb1.~..C888.
1.~-D1Cb1.~..ea... 'toull
IUy.Ltt......
2-"'.....
Scyn-
1.1.1-Trtca.L.r..C8888
~.t..ca.L.r..ca...
'01....
,r1.a1.c..ca...
nayl cU.raca.
Jrl".. (coca.L I
1aI~
A8888"ca...
A8888_~.L...
Aa-......
.......aaea......
......lIlfl..caaea...
.......,f1..c..cae..
''''.'.'","'''''
........b.1Ip.~.L."
.....ac .caca
'88871 a.Lc....L
bi..a..tby.Lb.ay.L,pacaa.Lac.
latY.L "..8Y.L paua1a&.
ca.,.....
D~.".(...,..ea~.....
DDaaa.'.Ir88
01 . a.~.L ,ataala'.
2..-Di88casya.....L
D1 . ..cpaptlL8.LaU
rs..eaaua...
IaMllet1. ~ . I.... tWl''''
Z",,,,1 ........1...
Z",,,l~
4-ll8UlFl~
""'1...
,.....cae...
P7ft88
~UI.
1."0
1m
-
4 - .
1m
1 - ..
11 - IS.OOO
581 - . ..00
J.."
170 - 6.aOO
1 - U.OOO
2 - no .000
2 - ..ao
1m
4 - '71D .000
3 - 5.
1 - J1
10
:s - 100
~ - 2.
1 - 120
1 - 2..00
"'0 - 1t0
lID
7 - J5
lID
1 - 10.000
1 - "
5 - '2
J.- 1.'00
170
121
201
I.
n - 2.000
n - 2.000
III
nl
,.
..
lS.500 - U.OIO
no
.5 - no
UI
...
UI
SSI.
411
" - 1..0.
UI
n - 1.UO
nl - ...
nl
11.'" - 1. ....
.4 - 1.."
.1 - 1.100
ns
1m
lilt
lilt
ID
1m
lilt
lilt
lilt
200
lilt
5 - 10
..
lID
lID
lID
lID
.
.. -
..
..
..
11
..
UI
..
..
..
.....
Aa8eaa8
..n-
c:a~-
~-
C:..,.C
108M
8&811.1
1&88
1.1 - U
4.1 - ,.
D.'. - 15.
S.I - 1.1.0
'.S - 112
4.' - II
'.1 - US
11 - tI.
J.O
44 - 112
1a..
1.1
11.2 - 11.1
2.' - ,.,
31
J'.. - n.
i ~~C8
c,au-
'.1 - at
11 - 2.010
(C811V2100,DaJl,. 11lDI. 'ft8~.
8D . Mt ca.t.ft-.
..n..
£=-1." ... cawae.....t. %.c. 1"'.
........ ...... .................
-t!:\ :i..: CI:"
~
- ...I
~~
at;
~C2
00
o
a.
-------
The dose-response evaluation presents available human health and
environmental criteria for the contaminants of concern, and
relates the chemical exposure (dose) to expected adverse health
effects (response). Included in this assessment are the'
pertinent standards, criteria, advisories and guidelines
developed for the protection of human health and the environment.
An explanation of how these values were derived and how they
shall be applied is presented below.
Cancer potency factors (CPFs) have been developed by u.s. EPA's
Carcinogenic Assessment Group for estimating excess lifetime
cancer risks associated with exposure to potentially carcinogenic
'chemicals. CPFs, which are expressed in units of (mg/kg/daY)-l,
are multiplied by the estimated intake of a potential carcinogen,
in mg/kg/day, to provide an upper-bound estimate of the excess
lifetime cancer risk associated with exposure at that intake
level. The term "upper-bound" reflects the conservative estimate
of the risks calculated from the CPF. Use of this approach makes
underestimation of the actual cancer risk highly unlikely.
Cancer potency 'factors are derived from the results of human
epidemiological studies or chronic animal bioassay to which
animal-to-human extrapolation and uncertainty factors have been
applied. '
Reference doses (RfDs) have been developed by u.s. EPA for
indicating the potential for adverse health effects from exposure
to chemicals exhibiting noncarcinogenic effects. RfDs, which are
expressed in units of mg/kqlday, are estimates of lifetime daily
exposure levels for humans, including sensitive individuals.
Estimated, intakes of chemicals from environmental media (e.q.,
water) can be compared to the RfD. RfDs are derived from human
epidemiological studies or animal studies to which uncertainty
factors have been applied (e.g., to account for the use of animal
data to predict effects on humans). These uncertainty factors
help ensure that the RfDs will not underestimate the potential
for adverse noncarcinogenic effects to occur.
C.
Exposure Assessment and Risk Characterization
The exposure assessment identified potential pathways and routes
for contaminants of concern to reach the receptors and the
estimated contaminant concentration at the points of exposure.
The risk characterization quantifies present and/or potential
future threats to human health that result from exposure to the
contaminants of concern at the EV site.
Excess lifetime cancer risks are determined by multiplying the
intake level with the cancer potency factor. These risks are
probabilities that are generally expressed in scientific notation
(e.g., 1xl0-6 or 1E-6 or 0.000001). . An excess lifetime cancer
risk of lx10-6 indicates that, as a plausible upper bound, an
13
-------
individual has a one in one million chance of developing cancer
as a .result of site-related exposure to a carcinogen over a 70-
year lifetime under the specific exposure conditions at a site.
The u.s. EPA generally attempts to reduce the excess lifetime
cancer risk posed by a Superfund site to a range of 1X10-4 to
1X10-6 (1 in 10,000 to 1 in 1 million), with an emphasis on the
lower end, 1X10-6, of the scale.
Potential concern for noncarcinogenic effects of a single
contaminant in a single medium is expressed as the hazard
quotient (HQ) (or the ratio of the estimated intake derived from
the contaminant concentration in a given medium to the
. contaminant's reference dose). By adding the HQs for all
contaminants within a medium or across all media to which a given
population may reasonably be exposed, the Hazard Index (HI) can
be generated. The HI provides a useful reference point for
gauging the potential significance of mUltiple contaminant
exposures within a single medium or across media. If the
estimated non-carcinogenic risk is less than 1.0, no adverse
effects are expected. If the calculated non-carcinogenic risk is
greater than 1.0, adverse health risks are possible.
The EV current land use exposure scenarios and the calculated
risk characterization associated with each exposure scenario are
as follows:
1.
2.
3.
4.
5.
Scenario
Inhalation of vapors from dry well area soils to:
a. on-site workers
b. children trespassing
Workers at Front st. businesses, basement infiltration
of groundwater vapors, inhalation exposure indoors.
Recreational fishermen using McCoy Creek, ingestion and
dermal exposure to water, fish ingestion.
Children trespassers, exposure to lagoon area soils
(ingestion, dermal and inhalation of vapors).
Child exposure to arsenic in dry well area soils
(ingestion, dermal).
Reasonable Max.
Carcinogenic Risk
Rea.sonable Max.
Non-carcinogenic Risk
--------------------------------------------------------------
1a
1b
2
3
4
5
1 X 10-6
1 X 10-7
8 X 10-7
5 X 10-4
3 X 10-8
1 X 10-7
2 X 10-7
0.03
0.03
0.0006
Groundwater
0.000004
0.04
(if VC detected in
at 5 ppb)
------
--------------------------------------------------------------
Note: bold numbers indicate risk is outside risk range set
forth in the NCP
14
-------
Scenario 2 indicates a possible adverse carcinogenic exposure.
At the time the risk assessment was completed, no vinyl chloride
had been detected in groundwater in the area where Front Street
businesses are located. However, because the detection limit
used was inadequate, vinyl chloride may be present at
concentrations below its detection limit but high enough to still
pose a significant health risk. To take this possibility into
account, the risk assessor assumed that vinyl chloride was
present at its qualitative detection limit (5 ppb). During a
subsequent investigation of surface water, monitoring wells 26
(shallow), 28, 30 and 35 were sampled and analyzed for vinyl
chloride at a detection limit of 1.5 ppb. vinyl chloride was
detected in monitoring well 30 at a concentration of 7 ppb; none
of the other monitoring wells sampled showed vinyl chloride above
the detection limit (1.5 ppb). Monitoring well 26 is located
.closest to Front street.
The future residential land use exposure scenarios that were
evaluated are as follows:
1.
2.
3.
4.
5.
Scenario
Residential use at dry well location (direct contact),
outdoor soil exposures (ingestion, dermal, and
inhalation of vapors). .
Residentia~ use at dry well location, infiltration of
vapors, indoor inhalation only.
Residential use of groundwater for drinking and
showering (ingestion and dermal).
Residential use of lagoon area soils (ingestion, dermal
and inhalation of vapors indoors and outdoors).
Residential use at dry well location, exposure to
arsenic (ingestion, dermal).
Reasonable Max.
Carcinogenic Risk
Reasonable Max.
Non-carcinogenic Risk
--------------------------------------------------------------
1 5 X 10-5 0.6
2 1 X 10-5 0.2
3 4 X 10-4 18.0
4 1 X 10-5 2.0
5 4 X 10-6 -----
--------------------------------------------------------------
Note: bold numbers indicate risk is outside risk range set
forth in the NCP
All of the future use scenarios indicate there is a low long-term
carcinogenic threat. Scenarios 3 and 4 both indicate an
unacceptable non-carcinogenic risk (greater than 1). The dry
well area soils, although posing a low long-term threat, has been
identified as the source of groundwater contamination.
15
-------
The exposure assumptions used in the EV RA are in accordance with
u.s. EPA's guidance document Risk Assessment Guidance for
Su~erfund: Volume 1 - Human Health Evaluation Manual (Part A).
December 1989, and are as follows:
Scenario
Exposure Exposure
Frequency Duration
365 days/yr 30 years
365 days/yr 5 years
120 days/yr 30 years
150 days/yr 5 years
365 days/yr 30 years
365 days/yr 5 years
365 days/yr 30 years
365 days/yr 5 years
365 days/yr 30 years
365 days/yr 5 years
365 days/yr 30 years
365 days/yr 5 years
120 days/yr 30 years
150 days/yr 5 years
365 days/yr 30 years
365 days/yr 5 years
1 - ingestion adult
child
.1 - dermal adult
child
1 - inhalation adult
child
2 - inhalation adult
child
3 - ingestion adult
child
4 - ingestion adult
child
4 - dermal adult
child
4 - inhalation adult
child
D.
Ecological Assessment
An ecological assessment of the EV site was undertaken in order
to identify any environmental resources at or near the site that
might be adversely affected by site contaminants. An ecological
assessment is a qualitative or quantitative appraisal of the
actual or potential effects of hazardous waste site contaminants
on plants and animals other than humans and domesticated species.
Organic and inorganic contamination in the dry well area, lagoon
area and fuel tank area soils is not expected to result in
adverse effects on terrestrial ecosystems due to the absence of
stressed vegetation or stained soils at the site. At the time
the ecological assessment was conducted, no surface soil sampling
had been completed anywhere at the site. Surface soil sampling
of lagoon area soils was subsequently conducted and confirmed
that contamination of metals existed in surface soils as well as
subsurface soils in this area.
16
-------
Chlorinated hydrocarbons, alkylbenzenes, and low concentrations
of several PAHs were found in groundwater near the former dry
well area. Groundwater is located 30 to 50 feet below ground
surface at the site and does not discharge to the site stirface.
Groundwater is therefore not expected to have anyon-site
ecological impacts. Groundwater does discharge to McCoy Creek
approximately one-half mile north of the site. Surface water
sampling of McCoy Creek indicated that contaminant levels from
the EV plume in the Creek are below MCLs. Therefore it does not
appear that contaminated groundwater entering McCoy Creek will
adversely affect plants or animals which utilize McCoy Creek.
'There are no
the EV site,
recreational
habitat.
rare or endangered species known to be resident at
nor are there species of special economic or
value for which the EV site serves as critical
u.S. EPA ambient water quality criteria (AWQC) for the protection
of freshwater species are available for 1,2-DCE and TCE, which
are designated chemicals of concern for the site. A computer
database search was conducted to assess the toxicological effects
of 1,2-DCE, TCE and vinyl chloride on aquatic flora and fauna.
The search included the AQUIRE, PHYTOTOX, ENVIROLIN~, BIOSDIS,
POLLUTION, ABSTRACTS, and other data bases.
The quotient method was chosen as the methodologies for assessing
risks to aquatic systems. The risk characterization results
,indicate that no significant effects on aquatic organisms are
expected to result from groundwater contaminants discharged to
McCoy Creek.
VII. ENVIRONMENTAL STANDARDS NOT MET AT THE SITE
In addition to posing unacceptable risks to receptors, the
Electro-Voice site does not meet certain applicable or relevant
and appropriate Federal or State environmental requirements
(ARARs) at this time.
A.
Groundwater
Table 4 lists the representative chemicals found in the
contaminated groundwater plume and the corresponding Federal and
Sta~e groundwater cleanup standards which the u.S. EPA believes
to be adequately protective of human health and the environment.
The off-property groundwater contains trichloroethene, 1,2-
dichloroethene, and vinyl chloride. All other chemicals
identified in the groundwater were detected only in the on-
property groundwater. The groundwater contaminant plume contains
concentrations of hazardous substances which exceed most of these
groundwater standards and cleanup criteria.
17
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TABLE 4
FEDERAL AND STATE GROUNDWATER CLEANUP STANDARDS
CHEMICAL
CAS #
MCL/MCL~
(ug /1)
MI"ACT 307
TYPE B*
(ug/l)
Volatile organic Compounds
-----------------------------------------------------------------
Alkylbenzene
Benzene
71-43-1
2-Butanone
78-93-3
Chloroethane
75-00-3
Chloromethane
74-87-3
1,2-Dichloroethane (1,2-DCA)
. 107-06-2
1,1-Dichloroethene (l,l-DCE)
75-35-4
1,2-Dichloroethene (1,2-DCE)
cis 156-59-2
trans 156-60-5
Ethyl Benzene
100-41-4
Toluene
. 108-88-3 .
1,1,1-Trichloroethane (l,l,l-TCA)
" 71-55-6
Trichloroethylene (TCE)
79-01-6
Vinyl Chloride
75-01-4
Xylenes (total)
1330-20-7
Semi-volatile organic compounds
Bis(2-ethylhexy)phthalate
117-81-7
Napthalene
91-20-3 .
* Groundwater protection criteria. .
. + proposed MCL and MCLG
18
20.00
5/0 1.00
----- 400.00
----- 9.00
----- 3.00
5/0 0.40
7/7 0.06
70 70.00
100 140.00
700/700 70.00
1,000/1,000 800.00
200/200 600.00
5/0 . 3.00
2/0 0.02
10,000/10,000 20.00
4/0+
2.50
-----
30.00
.
-------
The point of compliance for groundwater for cleanup purposes
shall be throughout the on-property plume within. the EV property
(see Figure 1). This first operable unit addresses only the
contaminated groundwater located within the EV property boundary.
Groundwater cleanup standards (Michigan's Act 307 Type B
standards, see Table 5 of this ROD) shall be applicable
throughout the on-property contaminated groundwater. Groundwater
background concentrations shall be required to be established
during the remedial design.
Groundwater Protection Goals and the National Contingency
Plan
The u.s. EPA's groundwater protection goal has been set forth in
the NCP as follows:
The national goal of the remedy selection process is to select
remedies that are protective of human health and the environment,
that maintain protection over time, and that minimize untreated
waste. Title 40 of the Code of Federal Regulations (40 CFR)
section 300.430(a) (1) (i).
The NCP states that the u.s. EPA expects to return usable ground
waters to their beneficial uses, wherever practicable, within a
time frame that is reasonable given the particular circumstances
of the site. Whenever restoration of groundwaters is not
practicable, u.s. EPA expects to prevent further migration of the
plume, prevent exposure to the contaminated groundwater, and
evaluate further risk reduction. 40 CFR section
300.430(a) (1) (iii) (F).
u.s. EPA expects to use institutional controls such as water use
and deed restrictions to supplement engineering controls as
appropriate for short-and long-term management to prevent or
limit exposure to hazardous substances, pollutants, or
contaminants... The use of institutional controls shall not
substitute for active response measures as the sole remedy unless
such response measures are determined not to be practicable...
40 CFR Section 300.430(a) (1) (iii) (D).
State of Michigan Groundwater Protection Goals
Michigan Act 307 provides ~or remedial action, at contaminated
sites within the State, which "shall be protective of the public
health, safety, and welfare and the environment and natural
resources." Additionally, all "remedial actions which address
the remediation of an aquifer shall provide for removal of the
hazardous substance or substances from the aquifer..." Michigan
Act 307 also provides for the determination of acceptable
criteria for groundwater remediation at the site.
19
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Cleanup Standards
U.S. EPA's groundwater cleanup policy is to attain Maximum
Contaminant Levels (MCLs) under the Federal Safe Drinking Water
. Act (SDWA); however, if cleanup to MCLs causes the residual risk
levels to exceed the 1 X 10-4 to 1 X 10-6 risk range, then the
U.s. EPA must apply risk-based cleanup levels to reach the goal
of protectiveness (1 X 10-6 excess lifetime cancer risk).
Michigan Act 307 Rules contain clean-up criteria which include
three different methods by which clean-up levels can be
determined. The levels are Type A, Type B, and Type C. The
'methodology for Type A clean-up is based on background levels or
method detection limits for chemicals of concern. The
methodology for Type B clean-up uses standardized risk
assumptions and exposure assumptions to determine clean-up levels
which will be protective of human health and the environment and
the use of the involved resource. Rules 299.5709 and 299.5J11 of
Michigan's Act 307 provide a thorough explanation on how to apply
the Type B clean-up to the chemicals of concern and calculate the
cleanup levels for the site. The methodology for Type C clean-up
reviews the actual conditions of the site; the uses, present and
future, of the site; a site specific risk assessment; and cost
effectiveness analysis. Rule 299.5717 of Michigan's Act 307
provides a thorough explanation of how to apply the Type C clean-
up to the chemicals of concern.
Michigan's Act 307, Type B clean-up criteria provide for the
calculation of risk-based clean-up standards at the 1 x 10-6
excess 'lifetime cancer risk level for each carcinogenic compound.
,These standards are usually more stringent than the corresponding
MCLs or non-zero Maximum Concentration Limit Goals (MCLGs). The
u.s. EPA has determined that Michigan's Act 307, Type B criteria
are protective and are applicable or relevant and appropriate to
the EV site.
Table 5 lists the Groundwater Remediation standards for the
Electro-Voice site. '
20
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TABLE 5
GROUNDWATER CLEANUP STANDARDS FOR THE ELECTRO-VOICE SITE
CHEMICAL
CAS #
(ug / 1 )
-------------------------------------------------------------
Alkylbenzene
20.00
Benzene
71-43-1
2-Butanone
78-93-3
Chloroethane
75-00-3
Chloromethane
74-87-3
1,2-Dichloroethane (1,2-DCA)
107-06-2
1,1-Dichloroethene (l,l-DCE)
75-35-4
1,2-Dichloroethene (1,2-DCE)
cis 156-59-2
trans 156-60-5
1.00
400.00
9.00
. 3.00
0.40
0.06
70.00
140.00
Ethyl Benzene
100-41-4
Toluene
108-88-3
1,1,1-Trichloroethane (l,l,l-TCA)
. 71-55-6
Trichloroethylene (TCE)
79-01-6
Vinyl Chloride
75-01-4
Xylenes (total)
1330-20-7
70.00
800.00
600.00
3.00
0.02
20.00
Semi-volatile organic compounds
Bis(2-ethylhexy)phthalate
117-81-7
Napthalene
91-20-3
2.50
30.00
NOTE:
Table 5 is the more stringent standard of the standards
presented in Table 4.
21
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B.
Dry Well Area Soils
Cleanup levels are developed in accordance with Michigan's Act
307 Type B criteria (aquifer protection criteria) or background,
whichever is more stringent. U.S. EPA shall require
establishment of background soil concentrations during the
remedial design.
TABLE 6
CHEMICAL
CAS #
MI ACT 307 TYPE B*
(ug/kg)
----------------------------------------------------------------
Volatile Organic Compounds
Alkanes
-----
Alkylbenzenes
-----
Benzene
71-43-1
Ethylbenzene
100-41-4
stYrene
100-42-5
Tetrachloroethene
127-18-4
Toluene
108-88-3
Trichloroethylene
79-01-6
Xylenes
1330-20-7
Semi-yolatile Organic Compounds
benzo(a) anthracene
56-55-3
benzo(k)fluoranthene
207-08-9
benzo(b)fluoranthene
205-99-2
benzo(a)pyrene
50-32-8
benzo(ghi)perlyene
191-24-2
Bis (2-ethylhexy) phthalate
117-81-7
Chrysene
218-01-9
dibenzo(a,h) anthracene
53-70-3
idenO[l,2,3-cd]pyrene
193-39-5
Napthalene
91-20-3
20.0
1,400.0
20.0
14.0
16,000.0
60.0
6,000.0
100.0
100.0
100.0
100.0
100.0
40.0
100.0
100.0
100.0
600.0
22
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TABLE 6 (continued)
CHEMICAL
CAS #
MI ACT 307
TYPE B*
(ug/kg)
----------------------------------------------------------------
PCB
PCB 1254
11097-69-1
1,000.0
Metals
Arsenic
0.4+
Beryllium
0.8+
* Groundwater protection criteria.
+ Local background levels will be used as the cleanup standard if
they are more stringent than Type B criteria.
C.
Lagoon Area Soils
During remedial design, and prior to capping of the lagoon area
soils, the horizontal and vertical extent of contamination shall
be determined.
A Type C ~emedy developed pursuant to Michigan's Act 307 Rules
has been determined to be relevant and appropriate for the lagoon
area soils because these soils are located in a natural
depression, and therefore are an unlikely area for future
development. However, children may trespass and play in this
area, both currently and in the future. The cap shall be
designed in accordance with the State of Michigan's hazardous
waste rules, Michigan's Act 64. A hazardous waste cap shall
eliminate or decrease dermal contact and ingestion of lagoon area
soils. The hazardous waste cap will also eliminate or decrease
infiltration into the soils, thereby decreasing the mobility of
cadmium, which was present at elevated levels in the lagoon area
soils and was detected above background levels in the soil column
at 26 feet deep (groundwater table is at 29.5 feet deep).
Cadmium is one of the more mobile metals, and may pose a threat
to groundwater in the future. See Figure 3.
23
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D.
Rationale for Further" Action
Actual or threatened releases of hazardous substances from this
site, if not addressed by implementation of the response'action
selected by this Record of Decision, may present an imminent and
substantial endangerment to public health, welfare, or the
environment. Therefore, based on the findings in the RI report
and the discussion above, a Feasibility study (FS) was performed
to focus the development of alternatives to address the threats
at the site. The FS report documents the evaluation of the
magnitude of site risks, site-specific applicable or relevant and
. appropriate requirements, and the requirements of CERCLA and the
. NCP, especially the groundwater protection policy, in the
derivation of remedial alternatives for the EV site.
VIII. SUMMARY OF ALTERNATIVES
The principal objective of remedial action is to eliminate and/or
reduce the threat or potential threat to human health and the
environment posed by the areas of concern. The selection process
for remedial actions is developed to address the specific threat
posed in an area of concern, and considers the chemicals of
concern and the routes of exposure, as well as effe~tive
technologies to address them.
The alternatives analyzed for the site are presented below. All
of the alternatives except the No Action Alternative include a
limited investigation for a lower aquifer. The purpose of the
lower aquifer investigation is to determine if a second aquifer
exists below the clay till layer in the vicinity of the dry well
area and if so, if that aquifer has been impacted by contaminants
from the EV site. .
The estimation of groundwater cleanup times as presented in the
Feasibility study (FS) report assumes that relative decrease in
contaminant mass (or concentration) with each pore volume is
constant. In other words, for each pore volume, the same ratio
of mass is removed from the system, but the total mass removed by
each successive pore volume is less. This constant reduction in
contaminant mass can be described by the first order exponential
decay equation used in the FS.
24
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Alternative 1: "No Action"
The NCP requires that a "No Action" Alternative be considered at
every site. It is used as a basis for comparison during the
evaluation of other alternatives. The "No Action" Alternative
assumes that no active remediation shall be conducted to address
potential public health and environmental problems.
Years to Attain Groundwater Cleanup Standards: 100+ years
Capital Cost: $0
Annual Operation and Maintenance (O&M) Cost: $0
Present Net Worth (over 30 years): $0 .
Alternative 2: xnstitutional controls; impermeable cap over all
contaminated soils.
As a component to this Alternative, institutional controls shall
require placement of deed restrictions on property and site
monitoring. Deed restrictions shall restrict future excavation
on the EV property and restrict groundwater usage throughout the
contaminant plume. Site monitoring shall include site
inspections and groundwater monitoring. The inspection program
shall include inspecting the fence for damage and monitoring for
any signs of trespassing. Groundwater monitoring shall track the
lonq-term aquifer quality through sampling.
A clay cap that shall meet the requirements of Michigan's Act 64
(a minimum of 3 feet of compacted clay, with 2 feet of additional
material including .a vegetative layer) over the dry well area and
lagoon area soils shall ensure long term effectiveness and
permanence of protection of human health and the environment.
The Resource Conservation and Recovery Act (RCRA) Subtitle C and
Michigan Act 64 are not applicable because the wastes in the
lagoon area soils are not RCRA listed wastes. RCRA Subtitle C
and Michigan ("MI") Act 64 have been determined to be relevant
and appropriate. RCRA Subtitle C/MI Act 64 are relevant because
the wastes which were disposed in the former lagoons are
sufficiently similar to RCRA listed wastes F006, F007 and/or
FOOS. RCRA subtitle C/MI Act 64 are appropriate because capping
with a RCRA Subtitle C/MI Act 64 hazardous waste cap shall
address the following concerns: a hazardous waste cap shall
provide long-term protection of human health and the environment,
specifically protection from direct contact or gardening of
plants which may uptake the soil contaminants and ,enter humans
via ingestion, at a future date; the additional degree of .
protection which shall be achieved with the hazardous waste cap
(as opposed to a solid waste cap, RCRA subtitle D or Michigan Act
641) is cost effective; a hazardous. waste cap shall decrease
infiltration into the soils, thereby decreasing the mobility of
cadmium, which was present at very elevated levels in the lagoon
area soils and was detected above background lev~ls in the soil
column at 26 feet deep (groundwater table is at 29.5 feet deep).
25
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Cadmium is one of the more mobile metals, and may pose a threat
to groundwater in the future. See Figure 3.
Based on groundwater modelling, it is estimated that without
treatment of the source area (the dry well area. soils),
groundwater may take over 100 years to clean itself up.
Years to Attain Groundwater Cleanup Standards: 100+ years
Capital Cost: $580,000
Annual Operation and Maintenance (O&M) Cost: $24,000
Present Net Worth (over 30 years): $940,000
Alternative 3A: Institutional controls; soil vapor extraction
and excavation and landfilling of sludge layer in dry well area
soils; cap over the lagoon area soils; pump and treat on-property
groundwater, monitoring of off-property groundwater.
This Alternative includes the institutional controls described in
Alternative 2; a Soil Vapor Extraction (SVE) system in the dry
well area and excavation, solidification, and off-site
landfilling of dry well area sludge; a hazardous waste cap which
meets the requirements of Michigan Act 64 over the lagoon area
soils; and pump and treat of on-property groundwate~ followed by
discharge to a local POTW. See Figure 4. .
A combination of SVE, excavation, solidification and off-site
landfilling of the sludge layer identified in the dry well area
soils shall be used to clean up the dry well area soils to the
cleanup levels specified in Table 6, page 21 of this ROD.
The SVE process acts as a vacuum to strip contaminated vapors
from the soil. These vapors shall then be treated before being
allowed to be released to the atmosphere. All releases to the
atmosphere shall meet the requirements of the Clean Air Act prior
to discharge. The treatment residuals shall be tested by the
Toxicity Characteristic Leaching Procedure (TCLP) to determine if
the treatment residuals are a characteristic waste as defined in
RCRA. Proper disposal of the treatment residual shall be
determined upon completion of the TCLP. Vapor extraction wells
shall be placed near the sources of contamination in the dry well
area. The SVE wells shall provide a consistent supply of oxygen,
remove waste products, and control soil moisture distribution.
After 2 to 5 years of operation, the dry well area soils shall be
sampled and analyzed at a laboratory approved by u.S. EPA to
determine how much contamination remains in the soi1s.
Excavation, solidification and off-site landfi1ling of the sludge
layer may be required by u.s. EPA. Prior to landfi1ling, the
solidified soils shall be tested to determine if the waste is
RCRA characteristic. If the ~aste is characteristic, Land
Disposal Restrictions (LDR) shall apply to its disposal. If the'
contamination levels are at or below the cleanup levels set forth
26
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in Table 6 of this ROD, no further action will be taken on these
soils. If contamination in the soils remains above the cleanup
standards, u.s. EPA shall evaluate further remedial activities.
Lagoon area soils shall be capped with a Michigan's Act 64
hazardous waste cap as described in Alternative 2.
This Alternative contemplates a pump and treat for groundwater
located within the EV property. Groundwater shall be treated on
the property by either granular or powdered activated carbon, air
stripping, chemical oxidation/reduction, or photolysis/oxidation.
After treatment, groundwater shall be discharged to a POTW. It
is estimated that it will take 2 years to clean-up the on-
property groundwater. Treatment residues from the groundwater
treatment system shall be tested by the TCLP to determine if it
is RCRA characteristic prior to disposal. RCRA Land Disposal
Restrictions may be applicable to these wastes. The remaining
off-property contaminated groundwater, from EV's northern
property boundary to McCoy Creek, shall be monitored.
Years to Attain Groundwater Cleanup
capital Cost: $3,000,000
O&M Cost: $330,000
Present Net Worth: $4,100,000
standards: 53 years
Alternative 3B: Institutional controls; 80il vapor extraction
and excavation and incineration of sludge layer in dry well area
soils; cap on the lagoon area soils; pump and treat on-property
groundwater, monitoring off-property groundwater.
This Alternative is identical to Alternative 3A, with the
exception that the dry well area source material, the sludge
layer, shall be excavated and incinerated off-site instead of
landfilled. Incineration of the source material will eliminate
long-term-risk associated with the highly contaminated sludge by
complete destruction of the contaminants.
Years to Attain Groundwater Cleanup
Capital Cost: $8,300,000
O&M Cost: $330,000
Present Net Worth: $9,400,000
standards: 53 years
27
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Alternative 4A: Institutional controls; soil vapor extraction of
dry well area soils followed by excavation and landfilling of
remaining sludge layer; cap on the lagoon area soils; pump and
treat all on- and off-property contaminated groundwater.'
This Alternative is identical to Alternative 3A, with the
addition of a comprehensive groundwater cleanup component. This
Alternative provides for pumping and treating the entire
contaminated groundwater plume which stretches from the EV
property to McCoy Creek (see Figure 5). On-property groundwater
shall be pumped and treated on-property and discharged to a POTW,
and off-property groundwater shall be pumped and treated and
discharged either to a POTW or to McCoy Creek. If off-property
groundwater is discharged to the creek, it shall be required to
meet the substantive requirements of an NPDES permit for
discharge of treated groundwater to a surface water body.
Treatment shall consist of either granular or powdered activated
carbon, air stripping, chemical oxidation/reduction, or
photolysis/oxidation. Any treatment residues from pumping and
treating the groundwater shall be tested by the TCLP to determine
if the residues are RCRA characteristic prior to disposal. It is
estimated to take 35 years to clean up off-property groundwater.
U.s. EPA has determined, based on the groundwater modeling
presented in the feasibility study report, that groundwater shall
reach standards that are protective of human health and the
environment in a shorter timeframe than may be achieved through
natural attenuation. The time savings that can be achieved by .
pumping and treating the groundwater versus natural attenuation
is estimated to be 30%-35%. The additional capital cost for an
off-property pump and treat is estimated to be $400,000.
Years to Attain Groundwater Cleanup Standards: 35 years
Capital Cost: $3,400,000
O&M Cost: $440,000
Present Net Worth: $5,700,000
Alternative 4B: Institutional controls; soil vapor extraction of
dry well area soils followed by excavation and incineration of
remaining sludqelayer; cap OD the lagoon area soils; pump and
treat all on- and off-property contaminated groundwater.
This Alternative is identical to Alternative 38, with the
addition of a comprehensive groundwater component. The
comprehensive groundwater component, consists of on-property and
off-property pump and treat. Groundwater from near the dry well
source shall be pumped and treated and discharged to a POTW, and
off-property groundwater shall be pumped and treated and
discharged either to a POTW or to McCoy Creek. If off-property
groundwater is discharged to McCoy Creek, it shall be required to
meet NPDES discharge permit requirements. Treatment shall
consist of either granular or powdered activated carbon, air
28
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stripping, chemical oxidation/reduction, or photolysis/oxidation.
Any treatment residues from pumping and treating the groundwater
shall be tested by the TCLP to determine if the residues are RCRA
characteristic prior to disposal. If the wastes are'
characteristic, RCRA Land Disposal Restrictions shall be required
to be met.
Years to Attain Groundwater Cleanup
Capital Cost: $9,000,000
O&M Cost: $440,000
Present Net Worth: $11,010,000
standards: 35 years
. Alternative SA: Institutional controls: excavate
all contaminated sludge and soils in the dry well
the lagoon area soils; pump and treat all on- and
contaminated groundwater.
and landfill
area; cap on
off-property
Alternative SA is similar to Alternative 4A with the exception
that all soils in the dry well area including the sludge shall be
excavated, solidified on-property and landfilled off-property at
a RCRA-permitted landfill. Dry well area soils shall be removed
to a depth of 40 to 50 feet. The excavated area shall be filled
with clean soil. Capping of the lagoon area shall be performed
as in the other alternatives. Groundwater extraction and
treatment shall be identical to the requirements set forth. in
Alternative 4A. See Figure 6.
Years to Attain Groundwater Cleanup Standards: 35 years
Capital Cost: $7,000,000
O&M Cost: $350,000
Present Net Worth: $8,900,000
Alternative SB: Institutional controls; excavate
all contaminated sludge and soils in the dry well
the lagoon area soils; pump and treat all on- and
contaminated groundwater. .
and incinerate
area: cap on
off-property
Alternative 5B is
that the dry well
incinerated at an
and landfilled.
identical to Alternative 5A with the exception
area soils including the sludge shall be
off-property facility rather than solidified
Years to Attain Groundwater Cleanup
Capital Cost: $11,000,000 .
O&M Cost: $350,000 .
. Present Net Worth: $13,000,000
standards: 35 years
29
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IX.
COMPARATIVE ANALYSIS OF ALTERNATIVES
In accordance with the NCP, the relative performance of each
alternative is evaluated using the nine criteria, 40 CFR"Section
300.430(e) (9) (iii), as a basis for comparison. . An alternative
providing the "best balance" of trade-offs with respect to the
nine criteria is determined from this evaluation.
A detailed analysis was performed on the alternatives using the
nine evaluation criteria in order to select a site remedy.
Alternatives 4 and 5 contain a component for treatment of the
off-property groundwater. Because a final remedy for groundwater
.will be addressed in the record of decision for the second
operable unit, these alternatives will not be evaluated further
in this first operable unit record of decision. The following is
a summary of the comparison of each alternative's strength and
weaknesses with respect to the nine evaluation criteria. The
nine criteria are: 1) overall protection of human health and the
environment; 2) compliance with applicable or relevant and
appropriate requirements (ARARs); 3) long-term effectiveness and
permanence; 4) reduction of toxicity, mobility or volume through
treatment; 5) short-term effectiveness; 6) implementability; 7)
cost; 8) state acceptance; and 9) community accepta~ce.
OVerall Protection of Human Health and the Environment.
This criterion addresses whether a remedy provides adequate
protection and describes how risks posed through each pathway are
eliminated, reduced, or controlled through treatment, engineering
controls, or institutional controls.
All alternatives, with the exception of Alternative 1 (No
Action), will reduce risks to human health. As the No Action
alternative does not provide protection of human health and the
environment, it is not eligible for selection and will not be
discussed further. Alternative 2 reduces human exposure to
contaminants through institutional controls. However,
institutional controls may not guarantee reduced risks to human
health in the future and institutional controls may not reduce
the risk to the environment.
Alternatives 3A and 3B further minimize the risks to human health
and the environment by treating the dry well area soils, which
are the principal threat, and treating the on-property
groundwater. Alternatives 3A and 3B rely on institutional
controls to protect human health and the environment from risks
posed by off-property groundwater. Institutional controls may
not guarantee reduced risks to human health in the future. A
final remedial decision for the off-property groundwater shall be
made in the record of decision for the second operable unit for
this site.
30
'.
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Compliance with Applicable or Relevant and Appropriate
Requirements (ARARs).
Alternatives 3A and 3B shall meet all ARARs for this first.
operable unit action, which consists of treatment of the dry well
area soils, closure of the lagoon area soils, and treatment of
the groundwater which is located on the EV property. Alternative
2 may not meet ARARs pertaining to the groundwater in this first
operable unit action in a reasonable time frame as Alternative 2
does not require active remediation of the groundwater.
Long Term Effectiveness and Permanence.
This criterion delineates the residual risk and evaluates the
ability of an alternative to maintain reliable protection of
human health and the environment over time, once cleanup
objectives have been met.
Alternatives 2 and 3 offer protection of public health and the
environment over the long term by treating or containing
contaminants. However, treatment alternatives are more effective
at eliminating risk in the long term than the containment'
alternatives.
Alternatives 3A and 3B are most effective at eliminating long
term risk because groundwater shall be treated and monitored, the
lagoon area soils shall be capped, and once the sludge layer has
been effectively treated or is removed, residual risk in tnose
soils shall be greatly decreased. Closure or other simila~
action shall be considered if the treatment system in the dry
well area is unable to reduce contaminant levels to equal or
below Michigan's Act 307 Type B cleanup levels.
u.s. EPA has decided to collect and evaluate additional data
regarding the off-property groudnwater before a final remedy is
selected for the off-property groundwater. A final remedy
decision for the off-property groundwater shall be addressed in
the record of decision for the second operable unit, after
additional information is gathered (see discussion in
"Documentation of significant Changes" at the end of this ROD).
Reduction of Toxicity, Mobility, or Volume Through Treatment.
This criterion evaluates the anticipated performance of the
treatment technologies a remedy may employ.
Alternatives 3A and 3B shall utilize treatment to reduce the
toxicity, mobility or volume of contamination in the dry well
area and in the on-property groundwater in order to protect human
health and the environment. Treatment of the dry well area soils
shall address the principal threat (sludge layer in the dry well
area).
31
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Alternative 2 does not utilize treatment for soils or
gro~ndwater.
Short-Term Effectiveness.
Short-term effectiveness addresses the period of time needed to
achieve protection and evaluates any adverse impacts on human
health and the environment that may be posed during the
construction and implementation of the remedy.
All of the alternatives involve construction at the
Protection of site workers and the community during
implementation of the selected alternative shall be
site health and safety plans.
site.
the
addressed by
No unacceptable short-term risks or cross-media impacts shall be
caused by the implementation of any of the alternatives. During
the period required for remediation, institutional controls shall
be used to mitigate the interim threats from possible use of
contaminated groundwater and possible exposure to contaminated
soils. The community and site workers may be exposed to
contaminants in the soils and the air, and to dust and noise
nuisance during implementation of the groundwater and soil
remedies. Standard safety. equipment, monitoring arid dust control
measures, shall mitigate any short-term risks.
Xmplementability.
This criterion considers the technical and administrative
feasibility of implementing an alternative, including the
availability of material and services needed to implement a
particular option.
There will be some implementation problems for all of the
alternatives. Deed restrictions which shall be required to be
placed on all properties under which the contaminated groundwater
flows could pose implementation problems because there are
nu.erous parcels of properties under which the contaminated
groundwater flows. capping and SVE are well established
technologies and should not be difficult to implement.
Incineration, as contemplated by Alternative 38, may pose
problems with respect to locating an off-site incinerator to
accept the waste. .
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Cost.
The estimated capital, annual operation and maintenance, and 30-
year present worth costs for each of the alternatives is'
presented below:
Alternative
Capital Cost
O&M
Present Worth
-----------------------------------------------------------------
1 $ ° $ ° $ °
2 $ 580,000 $ 24,000 $ 940,000
3A $ 3,000 ,,;00 $330,000 $ 4,100,000
3B $ 8,300,000 $330,000 $ 9,400,000
4A $ 3,400,000 $440,000 $ 5,700,000
4B $ 9,000,000 $440,000 $11,010,000
5A $ 7,000,000 $350,000 $ 8,900,000
5B $11,000,000 $350,000 $13,000,000
state Acceptance.
The last two criteria, state and community acceptance are
modifying criteria. .
The Michigan Department of Natural Resources (MDNR) .concurs
the U.S. EPA's selection of Alternative 3A as the preferred
remedial alternative for the first operable unit for the EV
as presented in the next section.
with
site
community Acceptance.
Based on the comments received by U.S. EPA, the community has
expressed its desire for u.s. EPA to carefully consider and
accept a proposal which EV presented to u.S. EPA during the
public comment period for the final remedy selection. U.S.EPA
has carefully considered EV's proposal and has decided to accept
several of the components of EV's proposal. u.s. EPA has
addressed why it has not accepted all components of EV's proposal
and the community's concerns in the attached Responsiveness
Summary. Briefly, the "common earth" cap which EV has proposed
for the lagoon area soils does not afford long-term protection.
The "common earth" cap is similar to a former Michigan Act 87 cap
which was designed to last for only 2 years. Maintenance
requirements for the "common earth" cap are expected to be
excessive in light of the fact that the lagoon area soils cap
shall need to be maintained indefinitely. In addition, the
"common earth" cap proposed by EV does not keep infiltration from
entering the contaminated lagoon area soils. Sampling conducted.
during the Remedial Investigation indicated that levels of
cadmium and arsenic above background levels were detected at
depths in the soil column of 26 feet and 23.5 feet, respectively.
The groundwater table is located at 29.5 feet. These sampling
results indicate that cadmium and arsenic are migrating toward
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the groundwater table and may pose a threat to the groundwater.
Cadmium is one of the more mobile metals. Therefore, a cap that
does not reduce infiltration into the lagoon area soils is not
sufficiently protective of the groundwater. .
EV has proposed that five years of off-property groundwater
monitoring be conducted instead of treatment of the off-property
groundwater. However, U.S. EPA's groundwater guidance and the
preamble to the NCP indicate that groundwaters which are
currently being used as a drinking water source, or groundwaters
which may be used as a drinking water source in the future (i.e.,
groundwaters which are not naturally unusable due to salinity or
'other natural factors), shall be actively remediated unless it is
impracticable. At the EVsite, MCLs have been exceeded and
unacceptable risk has been identified with the groundwater.
Also, the City of Buchanan's drinking water wells are located
4,000 feet west of the EV property. Therefore, in this first
operable unit,. the on-property groundwater shall be actively
remediated. The second operable unit will address a final remedy
decision for the off-property groundwater.
SELECTED REMEDY
x.
Based upon consideration of the requirements of CERCLA, as
amended by SARA, and the NCP, the detailed analysis of the
alternatives, and public comments, U.S. EPA has determined that
Alternative 3A (institutional controls; soil vapor extraction of
dry well area soils followed by excavation and landfilling of
remaining sludge layer; Michigan's Act 64 cap on the lagoon area
soils; pump and treat of the contaminated on-property groundwater
and monitoring of the contaminated off-property groundwater) is
the most appropriate remedy for the first operable unit to
protect human health and the environment.
Alternative 3A shall achieve substantial risk reduction through
soil vapor extraction followed by excavation of any of the
remaining 2,100 cubic yards of sludge; capping of the lagoon area
soils; and pumping and treatment of the contaminated on-property
groundwater and monitoring of contaminated off-property
groundwater. The dry well area soils, the source of the
groundwater contamination, shall be treated for 2 to 5 years with
SVE followed by excavation, solidification, and landfilling of
any remaining sludge. If the dry well area soils do not meet
cleanup standards after the SVE and excavation, additional
treatment with SVE or closure shall be considered by U.S. EPA.
The hazardous waste cap on the lagoon area soils shall ensure
long-term effectiveness and permanence because it shall eliminate
direct contact with the lagoon area soils both currently and in
the future and shall eliminate or reduce infiltration which
minimizes, if not eliminates contaminant movement in the soil
column. The groundwater pump and treat for the contaminated on-
property groundwater shall remediate the most highly contaminated
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groundwater first. Monitoring of the off-property groundwater
will allow u.s. EP~ to detect any changes in the off-property
groundwater before selecting a final remedy for. the second
operable unit. Alternative 3A provides the best balance 'of
benefits, with respect to the nine evaluation criteria for this
first operable unit among the alternatives considered.
A.
Remediation Standards
The purpose of this response action is to control risks posed by
ingestion and dermal contact with contaminated groundwater;
ingestion, dermal and inhalation contact with lagoon area soils;
.and to treat the principal threat (dry well area soils). The
future residential use scenario has been determined to pose an
excess lifetime cancer risk of 4 X 10-4 and a hazard index of 18
from use of groundwater for drinking and showering. This risk
relates to the concentration of vinyl chloride,
1,2-dichloroethene, benzene and trichloroethylene. Direct
contact, ingestion and inhalation of vapors from lagoon area
soils results in a hazard index of 2. This risk relates to the
concentration of lead (up to 83 mg/kg) in these soils. These
risks are outside u.s. EPA's acceptable risk range of 1X10-4 and
1X10-6 and exceeds the acceptable hazard index of 1~ Michigan's
Act 307 Rules sets forth cleanup levels for soils and
groundwater. Michigan's Act 307 Type C cleanup levels will be
achieved in the lagoon area soils, and Michigan's Act 307 Type B
cleanup levels shali be achieved in the dry well area soils and
in the groundwater located beneath the EV property. Off-property
groundwater shall be monitored until a final remedy decision is
made in tbe second operable unit ROD for this site.
XI.
STATUTORY DETERMINATIONS
Under its legal authorities, u.s. EPA's primary responsibility at
Superfund sites is to undertake remedial actions that achieve
adequate protection of human health and the environment. In
addition, Section 121 of CERCLA establishes several other
. statutory requirements and preferences. These specify that when
complete, the selected remedial action for this site must comply
with applicable or relevant and appropriate environmental
standards established under Federal and State environmental laws
unless a statutory waiver is justified. The selected remedy also
must be cost-effective and utilize permanent solutions and
alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. Finally, the
statute includes a preference for remedies that employ treatment
that permanently and significantly reduces the volume, toxicity,
or mobility of hazardous wastes as their principal element. The
following sections discuss how the selected remedy meets these
statutory requirements.
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A.
Protection of Human Health and the Environment
The selected remedy for the first operable unit for the EV site
protects human health and the environment through treatment of
the principal threat (dry well area soils), treatment of the
contaminated on-property groundwater, capping of the lagoon area
soils, and monitoring the off-property groundwater. The dry well
area soils shall be treated with SVE to reduce contaminant levels
to below Michigan Act 307 Type B levels. The sludge layer in the
dry well area soils shall be excavated, solidified and landfilled
if Type B cleanup levels cannot be met with SVE, If it is
demonstrated that the SVE and excavation of the sludge layer
cannot attain Michigan Act 307 Type B standards in the dry well
area soils, continued treatment with SVE or closure shall be
required by u.s. EPA. Lagoon area soils shall be contained with
a Michigan Act 64 cap to ensure long term effectiveness and
permanence from contact with these soils, and to eliminate
infiltration. . The contaminated on-property groundwater shall be
pumped and treated. The contaminated off-property groundwater
shall be monitored.
A limited investigation shall be conducted to determine "if a
lower aquifer exists at the site, and if so, if tha~ lower
aquifer is contaminated from EV site activities.
No unacceptable short-term risks or cross-media impacts shall be
caused by the implementation of the remedy for the first operable
unit. During the period required for remediation, institutional
controls shall be used to mitigate the interim threats from
possible use of contaminated groundwater and possible exposure to
contaminated soils. The community and site workers may be
exposed to organic and inorganic contaminants in the soils and
air, and to dust and noise nuisance during implementation of the
groundwater and soils remedies. standard safety equipment,
monitoring and dust control measures, shall mitigate any short-
term risks. .
Compliance with Applicable or Relevant and Appropriate
Requirements
The selected remedy shall compiy with the Federal and/or State,
where more stringent, applicable or relevant and appropriate
requirements (ARARs) listed below:
B.
Chemical SDecific ARARs
Chemical-specific ARARs regulate the release to the environment
of specific substances having certain chemical characteristics.
Chemical-specific ARARs typically determine the extent of clean-
up at a site.
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i. Groundwater
Federal ARARs
Maximum contaminant levels (MCLs) and, to a certain extent, non-
zero maximum contaminant level goals (MCLGs), the Federal
drinking-water standards promulgated under the Safe Drinking
Water Act (SDWA), are applicable to municipal water supplies
servicing 25 or more people. At EV, MCLs and MCLGs are not
applicable, but are relevant and appropriate since the sandstone
aquifer in the area of contamination is suitable for use as a
source of drinking water in the future. The sandstone aquifer is
currently being used as the drinking water source for the City of
Buchanan. The city wells are located 4,000 feet west of the EV
contaminant plume. MCLGs are relevant and appropriate when the
standard is set at a level greater than zero (for non-
carcinogens); otherwise, MCLs are relevant and appropriate. The
point of compliance for Federal drinking-water standards is
throughout the contaminated groundwater plume. For the purposes
of this operable unit ROD, the point of compliance for
groundwater for cleanup purposes shall be throughout the on-
property plume within the EV property (see Figure 1). This first
operable unit addresses only the contaminated ground~ater located
within the EV property boundary. The point of compliance for the
off-property groundwater will be addressed in the second operable
unit ROD.
state ARARs
The substantive provisions of Parts 6 and 7 of Michigan Act 307
rules and Rule 57 of Act 245 are relevant and appropriate to the
EV site. u.S. EPA has determined that acceptable standards for
groundwater clean-up, that have been derived under Type B
criteria, are protective in all the areas of the plume. Clean-up
levels derived under Type B criteria allow the aquifer to be
restored to its beneficial uses by achieving risk-based clean-up
standards. u.s. EPA has determined that these clean-up standards
are protective of human health and the environment. The point of
compliance for these standards is throughout the contaminated
groundwater plume. For the purposes of this operable unit ROD,
the point of compliance for groundwater for cleanup purposes
shall be throughout the on-property plume within the EV property
(see Figure 1). This first operable unit addresses only the
contaminated groundwater located within the EV property boundary.
The point of compliance for the off-property groundwater will be
addressed in the second operable unit ROD.
u.s. EPA has determined that Type B criteria yields groundwater
clean-up standards which also provide for the protection of
surface water quality, in turn protecting human health and the
environment.
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Discussion
Alternative 3A will achieve the groundwater cleanup levels
established pursuant to Act 307, Type B, for on-property'
groundwater. A final remedy decision for off-property
groundwater will be made in the record of decision for the
operable unit.
For the purposes of this operable unit ROD, the point of
compliance for groundwater for cleanup purposes shall be
throughout the on-property plume within the EV property (see
Figure 1). This first operable unit addresses only the
contaminated groundwater located within the EV property boundary. .
The point of compliance for the off-property groundwater will be
addressed in the second operable unit ROD1 the final operable
unit shall require compliance with Federal and state ARARS
throughout the plume.
second
ii. Soils
State ARARs
MERA - Act 307, P.A. 1982 (Michigan Environmental Re~ponse Act)
provides rules regarding the procedures for determining cleanup
criteria for contaminants in groundwater, surface waters, soils,
and air. Act 307 Type B criteria are relevant and appropriate
for the dry well area soils, and Act 307 Type C criteria are
applicable or relevant and appropriate for the lagoon area soils.
Discussion
The Michigan Act 307 Type B cleanup criteria
be met for groundwater and the dry well area
cleanup criteria shall be required to be met
soils.
shall be required to
soils. Type C
for the lagoon area
iii. Air
Federal ARARs
Regarding the Clean Air Act requirements, 40 CFR 50.1-50.12
requirements are applicable because emissions from the
groundwater and soil treatment systems are subject to Primary and
Secondary Ambient Air Quality Standards. Construction and
treatment system activities are potential sources of fugitive
dust, particulates, and VOCs and therefore, these activities are
subject to the TSP standard.
State ARARs
Certain state Air Pollution Act requirements are ARARs. Act 348
contains rules regarding emission limitations and prohibitions
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b
for particulate matter, fugitive dust, and VOCs. MAC Rule
336.1702, 336.1901, and 336.1373 requirements are applicable
since emissions from the treatment system are subject to state
standards for VOCs. Construction activities are potential"
sources of fugitive dust.
Discussion
The selected alternative shall meet air emission requirements
through use of proper emission control devices.
Location-sDecific ARARs
Location-specific ARARs are those requirements that relate to the
geographical position of a site. These include:
Federal ARARs
Executive Order 11988 and 40 CFR 264.18(b), Protection of Flood
Plains, are relevant and appropriate for this site. This Order
requires that the off-property groundwater treatment system be
located above 100-year flood plain elevation and be protected
from erosional damage. Any portion of the remedy that is
constructed within the 100-year flood plain must be adequately
protected against a lOO-year flood event (i.e., geotextiles
should be used to secure topsoil, etc.).
Section 404 of the CWA regulates the discharge of dredged or fill
material to waters of the United states. Construction of surface
water discharge points may be regulated under Section 404 of the
CWA; therefore, the substantive requirements of Section 404 are
relevant and appropriate to the remedial action at the site.
Action-sDecific ARARs
Action-specific ARARs are requirements that define acceptable
treatment and disposal procedures for hazardous substances.
Federal ARARs
For landfill closure, RCRA Subtitle C requirements are relevant
and appropriate because the lagoon area soils contain waste which
is sufficiently similar to listed and/or characteristic RCRA
Subtitle C waste. The Subtitle C cap is appropriate because
long-term effectiveness and permanence of protection of human
health and the environment shall be achieved with the cap.
RCRA Land Disposal Restrictions (LDR or Land Ban) are relevant
and appropriate as applied to the solidified sludge layer if
listed or characteristic RCRA Subtitle C hazardous wastes are
identified in the sludge layer during sampling and analysis. The
RI poorly defined inorganic contamination of the dry well area
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sludge layer, and it is not known if listed or characteristic
wastes are present in the sludge layer. Therefore, additional
sampling of this area shall be required, and, if listed and/or
characteristic RCRA Subtitle C hazardous wastes are identi~ied,
treatment requirements set forth in the Land Disposal
Restrictions at 40 CFR Part 268 shall be satisfied prior to land
disposal. In addition, LDRs are relevant and appropriate to any
treatment residuals generated during remediation if the treatment
residuals are determined to be listed or characteristic RCRA
Subtitle C hazardous wastes.
Disposal of nonhazardous wastes are regulated under 40 CFR 257
and these requirements are applicable to disposal of nonhazardous
wastes associated with this remedial action.
Disposal of the solidified sludge layer from the dry well area at
an offsite landfill, if determined to be a hazardous waste, shall
be requlated by 40 CFR 264.
40 CFR 264 and 40 CFR 268 (Subpart D) are applicable to
excavation which shall occur in the dry well area to remove the
sludge layer.
The only foreseeable manner in which the selected remedy may
require storage or disposal of hazardous waste is when or if the
groundwater treatment system requires emission control units to
capture or contain volatile organics derived from aeration of the
contaminated groundwater. The RCRA waste generation and
temporary storage regulations under 40 CFR Part 262 are then
applicable to that action. For example, spent activated carbon
canisters utilized as emission controls shall be managed as
characteristic waste if the waste canisters fail the Toxicity
Characteristic Leaching Procedure (TCLP) test.
The treatment contemplated for some contaminated groundwater
includes discharge of these liquids to a POTW. The POTW is
regulated under 40 CFR 403.5, and the National Pollution
Discharge Elimination System (NPDES). The actions of this remedy
shall meet the substantive requirements of NPDES.
Direct discharge of treatment system effluent is regulated by 50
FR 30784 (July 29, 1985), 40 CFR 122.44, 40 CFR 122(a), 40 CFR
122.21, 40 CFR 125.100, 40 CFR 125.104, and 40 CFR 136.1-136-4.
These requirements are all applicable to discharge of treated
groundwater to McCoy Creek.
Applicable post-closure care requirements to ensure that the site
is maintained and monitored are set forth in 40 CFR 264.310.
Responsibilities for offsite transportation of hazardous wastes
shall be applicable to the transportation of the solidified. dry
well area sludge layer. See 40 CFR 262, 263 and 49 CFR 100-199.
40
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b
State ARARs
The State of Michigan has been authorized to administer the
hazardous waste program within the State. Under Hazardous Waste
Management Act 64 of 1979, as amended, the State regulates the
generation, transport, treatment, storage, and disposal of
hazardous waste. Act 64 also regulates the closure, and the
postclosure care, of hazardous waste disposal facilities in the
State. As with RCRA Subtitle C, above, Act 64 is relevant and
appropriate to closure of the lagoon area soils. Act 64 is
applicable to the treatment residuals from on-site treatment.
Parts 4, 9, and 21 of the Water Resources Commission Act 245 of
1929, as amended, establishes rules for water quality by
prohibiting injurious discharges to surface water. These rules
are applicable to the discharge of treated groundwater to McCoy
Creek or to a POTW treatment system. .
The Michigan Environmental Response Act 307 of 1982, as amended
(Act 307), provides for the identification, risk assessment, and
evaluation of contaminated sites within the State. The U.S. EPA
has determined that the substantive provisions of Parts 6 and 7
of Act 307 are relevant and appropriate to the EV site. The Act
307 rules require that remedial actions shall be protective of
human health, safety, the environment, and the natural resources
of the state. To achieve this standard of protectiveness, the
Act 307 rules require that a remedial action achieve a degree of
clean-up under either Type A (clean-up to background levels),
Type B (clean-up to risk-based levels), or Type C (clean-up to
risk-based levels under site-specific considerations) criteria.
Type B criteria shall generally apply at sites where the desired
outcome is to allow the site to be returned to unrestricted use
at the completion of the remedial action. Type C cleanups shall
generally apply at the largest and most complex sites, and at
sites where the uses of the property are expected to be limited
at the completion of the remedial action. U.s. EPA has
determined that the Type C criteria are appropriate for the
lagoon area soils since this area of the site is located in a
natural depression area and therefore use of the area would be
limited (e.g., homes would probably not be built in a natural
depression area). However, protection is still required since
homes could be built on the EV property where the building
currently exists and the lagoon area soils would become the
backyard to these future homes. Type B criteria are appropriate
for the groundwater and the dry well area soil portions of this
remedy because the goal of the selected remedy is to return the
groundwaters and dry well area soils to unrestricted use.
C.
Cost-Effectiveness
The selected remedy is cost-effective because it has been
determined to provide overall effectiveness proportional to its
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costs, the net present worth value being $4,100,000. The only
alternatives that are less costly than the selected alternative
are Alternatives 1 and 2.
utilization of Permanent Solutions and-Alternative
Treatment Technologies (or Resource Recovery
Technologies) to the Maximum Extent Practicable
u.S. EPA has determined that Alternative 3A represents the
maximum extent to which permanent solutions and treatment
technologies can be utilized in a cost-effective manner for the
first operable unit for the EV site. u.S. EPA has determined
that Alternative 3A provides the best balance of tradeoffs in
terms of long-term effectiveness and permanence, reduction in
toxicity, mobility, or volume achieved through treatment, short-
term effectiveness, implementability, and cost, also considering
the statutory preference for treatment as a principal element and
considering State and community acceptance for the first operable
unit.
D.
Alternative 3A shall significantly reduce the inherent hazards
posed by the contaminated soils by treatment of dry well area
soils with soil vapor extraction and excavation of the source
(sludge layer), if necessary.
Alternative 3A treats the principal threat, the dry well area
soils which are the source of groundwater contamination.
Alternative 3A affords greater long term effectiveness and
permanence and affords greater reduction of toxicity, mobility,
or volume through treatment than Alternative 2 because
on-property groundwater shall be treated. Short-term
effectiveness is similar for all the alternatives considered,
approximately 1 year. All of the alternatives will have similar
implemen~ability problems. Alternative 3A is the least costly
option which provides for on-property groundwater treatment.
Alternative 3A provides a significantly greater degree of long-
term effectiveness and permanence, reduction of toxicity,
mobility and volume than Alternative 2, and is cost-effective.
E.
Preference for Treatment as a Principal Element
By treating the dry well area soils, which are the source of the
groundwater contamination, and then excavating, solidifying and
landfilling the remaining sludge layer, the selected remedy
addresses the principal threat posed by the site through the use
of treatment technologies. Therefore, the statutory preference
for remedies that employ treatment as a principal element is
satisfied for this operable unit.
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b
XII. DOCUMENTATION OF SIGNIFICANT CHANGES
A significant change has been made in the remedy selected for the
EV site since the publication of the FS and the proposed P1an in
September 1991. The remedy recommended in the Proposed Plan was
Alternative 4A: institutional controls; soil vapor extraction of
dry well area soils followed by excavation and 1andfi11ing of
remaining sludge layer: Michigan's Act 64 cap on the lagoon area
soils: pump and treat all on- and off-property contaminated
groundwater. Since publishing the Proposed Plan, U.S. EPA has
determined that an operable unit approach is more appropriate for
this site than selection of a final remedy at this time. The
Agency's decision to utilize an operable unit approach was made
after considering the substantial number of public comments which
preferred monitoring the off-property groundwater rather than
actively remediating the off-property groundwater through pump
and treat. U.S. EPA has determined that the operable unit
approach is more appropriate at this time because it allows a
more focused, logical approach, whereby the contaminated soils,
which are the source of groundwater contamination, and the more
highly contaminated groundwater, the on-property groundwater, are
treated first. The treatability study is required under this
first operable unit ROD. U.S. EPA will evaluate the .effect of a
treatability study on soils and on-property groundwater prior to
making a final remedy decision for the off-property groundwater
in the second operable unit ROD.
U.s. EPA has determined that the first operable unit, which is
addressed by this ROD, shall consist of institutional controls:
soil vapor extraction and excavation and landfilling of the
sludge layer in dry well area soils: Michigan's Act 64 cap over
the lagoon area soils: pump and treat on-property groundwater,
and monitoring of off-property groundwater. A treatability study
shall be conducted on the dry well area soils arid the on-property
groundwater beginning the summer of 1992 for a period of one
year. The treatability study will be conducted with the
cooperation of U.s. EPA's Superfund Innovative Technologies
Evaluation (SITE) Program in Cincinnati, Ohio. The treatability
study shall test the effectiveness of an innovative technology
called the Subsurface Volatilization and Vapor System (SVVS) ,
which is a combination air sparging/bioremediation system, and
should be effective at cleaning up both the dry well area soils
and the on-property groundwater at the EV site. The
determination that this innovative technology may be effective at
this site was made in November 1991. The advantages to the SVVS
system are that most of the treatment is completed in-situ and
the system is expected to clean up the soils and groundwater
faster and be less expensive than conventional treatment systems.
For further information regarding this technology, consult the
Administrative Record for this site. If the treatability study
indicates the SVVS system is effective at cleaning up the
contaminants at the EV site, U.S. EPA will consider using this
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technology to clean up the off-property groundwater in the second
operable unit ROD in accordance with CERCLA and the NCP.
The Record of Decision (ROD) has also reordered the manner' in
which the chosen technologies will be applied to the dry well
area soils, in accordance with EV's suggestion. The Proposed
Plan indicated that excavation, solidification and landfilling of
the sludge layer in the dry well area soils would be completed
first, followed by soil vapor extraction (SVE) to remove residual
contamination. The ROD indicates that SVE will be completed on
the dry well area soils for 2 to 5 years followed by excavation,
solidification and landfilling of any remaining sludge.
The remedy selected for this first operable unit is Alternative
3A: institutional controls; soil vapor extraction and excavation
and landfilling of sludge layer in dry well area soils;
Michigan's Act 64 cap over the lagoon area soils; pump and treat
on-property groundwater; and monitoring of off-property
groundwater. This change in remedy selection is a logical
outgrowth based on the information available during the public
comment period and the comments submitted. Alternative 3A has
been determined to provide the most appropriate balance of
tradeoffs among the alternatives, with respect to pertinant
criteria, given the limited scope of this action.
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