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Superfund
Record of Decision:
Clare Water Supply, MI
EPA Report Collection :
Informatirm Resource Center
US EPA Region 3
PhiladoIphlaa PA 19107

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50272-101
REPORT DOCUMENTATION II. REPOATNO. I 2.
PAGE EPA/ROD/R05-90/140
3. A8dp1ent'a AcC888Ion No,
4. TItle end SubIItI8
SUPERFUND RECORD OF DECISION
Clare Water Supply, MI
First Remedial Action
7. AuthM(a'
5. Report D-
08/30/90
8.
8, Performing OrvenlutJon Rapt. No.
8. PerlOl'ming OrgainlutJon N8m8 end Addr8u
10. ProjectlTulllWoriI Unit No.
t t. Contreet(C) or GranI(G) No.
(C)
12. Sponeorlng Org8nlzadon N8m8 end Add....
U.S. Environmental Protection
401 M Street, S.W.
Washington, D.C. 20460
(G)
t3. Type of Report. Pwtod eownd
Agency
800/000
t4.
15. Suwl8mentary No..
18. Abalraet (Umit: 200 WOI'de)
The Clare Water Supply site is the public water supply system for the city of Clare,
Clare County, Michigan. The Clare Water Supply system withdraws ground water from four
municipal wells (MW) in the site wellfield, each tapping an unconsolidated sand aquifer.
In 1981, ground water sampling revealed contaminants including chlorinated hydrocarbons
in two of the wells (MW #2 and MW #5) in the northeastern portion of the site. An
industrial area containing approximately 14 manufacturing and retailing businesses
operates west of the contaminated wells. 50il samples extracted from this industrial
area indicate soil contaminated with TCE and DCE. In addition, a nearby settling lagoon
contains solvents and heavily contaminated sediments. EPA conducted a short-term study
that determined that the major source of ground water contamination resulted from
contaminants leaching out of soil on the industrial properties, entering a shallow
perched aquifer, and migrating to the deeper aquifer that serves the municipal
wellfield. The Clare Water Supply wellfield is the sole source of drinking water for
the community. Remedial actions for this site will focus on two operable units. The
first, Operable Unit One (OU1), an interim remedy addressing TCE contamination of the
drinking water supply, will be implemented in this Record of Decision (ROD). A
(See Attached Page)
17. Document Anary"a L DaacriptOl'a
Record of Decision - Clare Water Supply, MI
First Remedial Action
Contaminated Medium: gw
Key Contaminants: VOCs (TCE)
b. IdandfleralOpen-Endad Tanna
c. COSA TI Fl8Id1Group
18. Availability 51818manl
18. S8cur1ty CI... (Thla Report)

None

20. Security CI- (Thla Paga)
Nnno:>
21. No. o' Pall"
17
22. Price
See ANSI-Z38.18
5H In./rUCtJona on Rave,..
(4-71)
(Form8fty NTlS-35)
Dapartmant o' Commerce

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EPA/ROD/R05-90/l40
Clare Water Supply, MI
First Remedial Action
Abstract (continued)
subsequent ROD will
soil contamination.
VOCs including TCE.
address OU2, the remaining ground water contaminants as well as
The primary contaminants of concern affecting the ground water are
The selected remedial action for this interim remedy includes installing and operating
an air stripper to treat the ground water, modifying pipelines on the existing water
supply system, monitoring treated water from the air stripper prior to its release into
the water supply system, and monitoring air emissions from the air stripper. The
estimated present worth cost for this interim remedial action is $1,284,059, which
includes an annual O&M cost of $61,000 for 30 years.
PERFORMANCE STANDARDS OR GOALS: This ROD will remediate ground water TCE
TCE-degradation components to meet Safe Drinking Water Act MCLs including
Additional chemical-specific ground water goals will be determined in the
ROD.
and
TCE 5.0 ug/l.
subsequent

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DECLARATION FOR THE RECORD OF DECISION
SITE NAME AND LOCATION
Clare Water Supply
Clare County, Michigan
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the Clare Water Supply site, in Clare,
Michigan, which was chosen in accordance with the requirements of 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 document explains the factual
and legal basis for selecting the remedy for this site. The information supporting this remedial action
decision is contained in the administrative record for this site.
The State of Michigan concurs with the selected remedy.
ASSESSMENT OF THE SITE
I
J
Actual or threatened releases of hazardous substances from this site, if not addressed by implementing
the response action selected in this ROD, may present an imminent and substantial endangerment to
public health, welfare, or the environment.
DESCRIPTION OF THE SELECTED REMEDY
This interim action operable unit is the first of two operable units for the site. This operable unit addresses
contamination of drinking water by eliminating or reducing the risks, through treatment and engineering
controls, posed by the distribution of contaminated drinking water. The second operable unit will address
contaminated soils and groundwater and will be the final response action at the site.
The major components of the selected remedy include:
o
Installation and operation and maintenance of an air stripper and minor piping or power
supply modifications to the existing system; and
o
Monitoring of water treated by the air stripper prior to release into the distribution system.
Inlet water to the air stripper will also be monitored on a regular basis for contaminant
concentrations to ensure air emissions being stripped off the water are within an
acceptable range.

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)
DECLARATION
This interim action is protective of human health and the environment, complies with Federal and State
applicable or relevant and appropriate requirements directly associated with this action, and is cost-
effective. This action utilizes permanent solutions and alternative treatment technologies to the maxirrum
extent practicable, given the limited scope of this action. This action does not constitute the final remedy
for the Clare Water Supply site and the statutory preference for remedies that employ treatment that
reduces toxicity, mobility, or volume as a principal element will not be satisfied by this interim action.
Subsequent actions are planned to address fully the principal threats posed by this site.
k:&(!t}'~/

~fialdas V. Adamkus
(T - Regional Administrator
U.S. EPA - Region V
f"~ ~iJ//99v
Date
- 2-

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DECISION SUMMARY
SITE NAME. LOCATION. AND DESCRIPTION
The Clare Water Supply is in the southwestern quadrant of the City of Clare. Michigan; in the southeast
1/4 of Section 34, Township 17 North, Range 4 West of Grant Township, Clare County, Michigan. The
Clare Water Supply system withdraws groundwater from four municipal wells (MW) in the area, each
tapping an unconsolidated sand aquifer which occurs between approximately 30 to 80 feet below the
surface. Two of the wells. MW #2 and MW #5, are located in the northeastern portion of the site. Based
on sampling since 1981, these wells have been shown to be contaminated. The contaminants in these
wells consist primarily of chlorinated hydrocarbons. Two uncontaminated wells, MW #6 and MW #7, are
located generally south and southwest of the contaminated portion of the site, respectively. The Clare
Water Supply is the Public Water Supply for the 3,300 residents of Clare, Michigan. This has been found
to be the only feasible source of drinking water for the community.
West of the contaminated wells, approximately 14 manufacturing and retail businesses are operating. It
appears that several of these facilities may be or have been the location of contamination source areas.
Current or past operations which contributed to the contamination include lagoon storage. and
underground and above ground tank storage. North and east of the contaminated municipal wells,
additional source areas appear to include refueling and storage operations and a dry cleaning operation.
Currently, seven potential source areas have been identified. Several of these source areas contain
identical contaminants.
The site is generally bounded to the north by 5th Street (U.S. Highway 10). The western boundary of the
site roughly corresponds to the western side of the Mitchell Property, and the wellfield is bounded to the
east by Maple Street (Figure 1). The Ann Arbor railroad line traverses the sije from the south to north and
the C&O Railroad line crosses the site at the northwest edge. The Little Tobacco Drainage Ditch flows
across the wellfield entering from the southern border of the industrial area located directly west.
northwest of the municipal wellfield. The drainage ditch is spring fed before it enters the industrial area
and receives input from surface runoff. The flow in this drainage ditch is intermit1ent and it rarely exceeds a
few inches in depth.
Flow from the drainage ditch infiltrates the soils at the western edge of the well field. On the eastern edge
of the wellfield, surface flow from the little Tobacco Drainage Ditch joins the Little Tobacco River and
continues eastward. Other local surface water includes the Tobacco River, approximately one-half mile
north of the well field, and Shamrock Lake, approximately 1 mile northeast of the well site.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
In December, 1981. the Clare municipal wells were sampled by the Michigan Department of Public Health
(MDPH) for organic compounds. The Clare wells were selected as part of a statewide survey of municipal
wells due to their shallow depth, lack of protective clay overburden, and proximity to industrial plants. The
sampling revealed Volatile Organic Compound (VOC) contamination in MW #2 and MW #5. The
contaminants were identified as chlorinated hydrocarbons and included Trichloroethene (TCE) and
dichloroethene (DCE). The MDPH determined that the aeration process, which the city used to remove
iron from the drinking water, and blending of the water from the contaminated wells (MW #2 and MW #5)
with water from ihe uncontaminated well (MW #6) would effectively remove some of the contamination
from the water prior to distribution. The City of Clare agreed to use MW #5 as little as possible, and to
blend the water primarily from MW #2 and MW #6. In testing the distribution system for contamination,
water from

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:..
Figure 1
Site Location Map
Clare Municipal Well Field Site
Clare, Michigan
I
J

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MW #5 was sampled prior to treatment and then after treatment. Testing results indicated that the iron
removal aeration treatment removed approximately 67% of the TCE contamination through volatilization
during the forced draft aeration (45 ppb before treatment, 15 ppb after treatment). DCE concentrations
were not significantly aHected by the aeration (11 ppb before treatment, 10 ppb after treatment).
Blending of water from the least contaminated wells facilitated a further reduction in contaminant
concentrations within the tap water system. Water is still aerated and blended in this manner before
delivery .
Well log data from a 1982 monitoring well drilling program conducted by the Technical Assistance Team
(TAT), a contractor working on behalf of the U.S. EPA, established the existence of clay lenses that
covered the area west of the municipal well field. Soil samples from the industrial area indicated grossly
contaminated soils near at least four industrial sites. A settling lagoon, located on the Essex/Holley
Carburetor property, was found to contain solvents and heavily contaminated sediments. The lagoon was
noted to have an oily film on top, and during storm conditions, the lagoon contents generally overflowed
into the drainage ditch.
This short-term study indicated that the major sources of soil and groundwater contamination were most
likely located in the industrial area directly west of the well site. Contaminants are believed to be leaching
out of soils on the industrial properties, entering a shallow perched aquifer, and migrating to the deeper
aquifer that serves the municipal well field. Contaminants appear to be transported by both surface water
(the drainage ditch) and groundwater flow pathways.
In November 1982, the Clare site was evaluated using the Hazard Ranking System (HRS) and a score of
32.26 was assigned. The site was the proposed to Group 7 of the National Priorities List (NPLj. The site i
was listed as final on the NPL on September 21, 1984 with a final score of 38.16.
In September 1984, the MDNR requested that a RemediallnvestigationfFeasibility Study (RifFS) for the!
Clare Water Supply be initiated in fiscal year 1985. Concurrent to this request, a short-term hydrogeologic
investigation was conducted by the MONR. The objective of this study was to identify potentially
responsible parties (PRPs) so that they could be requested to undertake the RVFS.
On September 27, 1985, a Consent Order was signed, binding the U.S. EPA and the PRPs: Colt
Industries (now COltec), Ex-Cello Corporation, Ransburg Corporation, and United Technologies
Automotive, to complete a RifFS at the Clare Water Supply field in Clare, Michigan. The Remedial
Investigation (RI) was initiated in September, 1988.
From September 6, 1988 to November 12, 1988, the following Phase I field work was completed by the
PRPs: installation of 24 shallow (5-7 feet deep), 11 intermediate (18-47 feet deep), and 4 deep (55-105)
groundwater monitoring wells; completion of 41 soil borings; collection of 6 sediment and 12 surface
water samples from the Little Tobacco Drainage Ditch; sampling and measuring water levels of all ground-
water monitoring wells; and geophysical surveys. This field work was designed to identify the sources of
the contaminants, determine the vertical and lateral extent of contamination, locate contaminant migration
pathways, and evaluate the public health and environmental risks associated with the site.
Phase II of the Remedial Investigation (RI) field work was conducted from June 13, 1989 to August 16,
1989. Field activities during this period included geophysical surveys, 4 additional shallow ground-water
monitoring well installations, 6 additional intermediate depth groundwater monitoring well installations, 10
soil borings. drain tile investigations with 14 test pits, 6 piezometer installations, a 72 hour pump test of the
aquifer serving the wellfield, sampling of ground water, 5 surface water samples from the drainage ditch
and ground water level measurements.
A draft Remedial Investigation Report prepared by the PRPs was submitted in December of 1989. This
report revealed that levels of DCE and Vinyl Chloride, both of which may be formed as degradation
2

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products of TCE, were at levels equal to or greater than the MCL in MW #5 and that DCE equalled the
Maximum Contaminant Level (MCL) in the distribution system water during at least 1 sampling episode in
1989.
j
v
COMMUNITY PARTICIPATION
A Community Aelations Plan for the Clare Water Supply site was finalized in February, 1989. This
document lists contacts and interested parties throughout government and the local community. It also
established communication pathways to ensure timely dissemination of pertinent information.
Subsequently, a fact sheet outlining the AI sampling program was distributed in August of 1988. An RI
initiation public meeting was also held at that time in Clare. The Proposed Plan for the interim action at the
Clare Water Supply site was released to the public on July 12, 1990. All of these documents, including
the analytical data upon which this decision is based, were made available in both the administrative record
and the information repository maintained at the Garfield Memorial Library at 4th and McEwan Streets in
Clare. The notice of availability for these documents was published in the Mount Pleasant Morning Sun
on July 6,1990, in the Clare Sentinel on July 10, 1990 and in the Clare County Review on July 9,1990.
A public comment period was held from July 12, 1990 through August 13, 1990. In addition, a public
meeting was held on July 18, 1990 to present the results of the initial data submissions and the preferred
alternative as presented in the Proposed Plan for this interim action. All comments which were received
by EPA prior to the end of the public comment period, including those expressed verbally at the public
meeting, are addressed in the Responsiveness Summary which is attached to this Record of Decision.
SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION WITHIN SITE
STRATEGY
U.S. EPA has organized this project into two operable units. The first operable unit is an interim action to
address contamination of the drinking water supply by Trichloroethene (TCE) and TCE-degradation
products. The second operable unit will constitute the final response action at the site addressing the
remaining groundwater and soil contamination. The intermittent occurrence of degradation products at
levels approaching or equalling the MCL in recent samples of the water in the distribution system presents
a potential for an imminent and substantial endangerment to the persons served by the water supply prior
to completion of the RifFS for the source areas.
This interim action is intended to provide for protection of public health before the occurrence of a rise in
the level of TCE breakdown products which exposes the public to drinking water which exceeds MCLs.
This interim action is intended to continue until the subsequent remedial investigation/feasibility study
addressing overall aquifer and soil contamination has been completed. This expedited operable unit
remedial action is considered to be consistent with achieving a final site remedy.
SUMMARY OF SITE CHARACTERISTICS
Contaminants that have been detected in the groundwater include: vinyl chloride, trichloroethene (TCE),
1,1-dichloroethane (1 ,1-DCA), methylene chloride, benzene, bromoform, chlorodibromomethane, 1,1,2-
trichloroethane (1 ,1 ,2-TCA) and 1,2-dichloroethane (1,2-DCA). Only TCE and DCE contaminants have
been continuously detected in measurable concentrations in the municipal well water. Concentrations 01
TCE as high as 48 ppb and DCE at 26 ppb have been found in the aquifer that services the City Water
3

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Supply wells. Concentrations detected in the public water supply at the tap have been consistently lower
than those found in the production wells. Contaminant concentrations in MW #2. MW #5, and the
distribution system are shown in Table 1 below.
TABLE 1 : CONTAMINANT CONCENTRATIONS FOUND IN RECENT SAMPLING
ACTIVITIES         
  Distribution Municipal Municipal Maxirrum 
  System Tap Well #2  WeU#5 Contaminant 
  11/88 9189 1"88 9/89 11/88 9/89 Level lMCU 
Trichloroethene 3 0 7 4 21 14  5 
, ,2-Dichloroethane 5    0  5 
Trans-' ,2  6 0 26 35 13 14   
Dichloroethene         
Vinyl Chloride 0 0 2 2  0  2 
. All numbers represent micrograms per liter which is equal to parts per billion.  
SUMMARY OF SITE RISKS
Persons who utilize municipal well water from the Clare Water Supply wellfield are identified as the
population at risk. The primary routes of exposure to contaminants in groundwater are ingestion,
inhalation of volatiles and dermal absorption. Trichloroethene, 1,2-dichloroethene. methylene chloride,
bromoform, dibromochloromethane and vinyl chloride detected in the distribution system water are the
contaminants of concern. Trichloroethene, methylene chloride, and vinyl chloride are probable or actual
human carcinogens. The maximum carcinogenic risk from exposure to contaminated drinking water is 4 x
10-4 (4 excess cancer cases in ten thousand persons). As part of the ongoing RifFS, a baseline risk
assessment will be prepared.
Actual or threatened releases of hazardous substances from this site, if not addressed by implementing
the response action selected in this ROD, may present an imminent and substantial endangerment to
public health, welfare, or the environment.
DESCRIPTION OF ALTERNATIVES
Two alternatives were proposed for the purposes of this interim action. These alternatives address only
the municipal well water which is supplied to the residents of Clare.
ALTERNATIVE 1
NO ACTION WITH CONTINUATION OF CURRENT AERATION AND
BLENDING TREATMENT
The Superfund program requires that the "no-action" alternative be considered at ev~ry site. Under this
alternative, EPA would take no further action to control the contaminated municipal water. The current
treatment procedures being implemented by the City of Clare (Aeration and Blending) would however. be
continued.
4

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Applicable or relevant and appropriate requirements (ARARs) for the No Action alternative are Federal
drinking water standards and Michigan Department of Public Health standards and requirements adopted
under the Wellhead Protection Program. Drinking water MCLs may potentially be exceeded under the no
action alternative.
There is no cost or operation and maintenance (O&M) associated with the No Action Alternative. Annual
costs to operate the present aeration and blending system were not considered.
AL TERNATIVE 2
PACKED TOWER AERATION OF WATER FROM MW#2 AND #5
PRIOR TO DISTRIBUTION
In the proposed treatment scenario, water from wells MW #2 and MW #5 will be fed to the inlet of the
proposed air stripper system as shown in figure 2. The air stripper will be sized to handle 2,100 gallons per
minute (gpm). This is the maximum flow rate which could be encountered if MW #2 and MW #5 were
pumping water at their maximum capacity.
Because the current piping system allows for the flow of water from any well to either of the aerators, no
major piping modifications are anticipated. However, installation of a pipe from the mutual MW #2 and MW
#5 piping line to the air stripper will be required. Due to this modification, a pipe line will be added to the
system to also allow water to flow from MW #6 and MW #7 to either of the two existing aerators if the need
should occur.
Monitoring of the water coming into and out 01 the treatment system would be required during the life of i
the treatment process. The duration of this treatment p~ocess is yet to be determined and will be .
dependent upon the decision to be made for the second operable unit. ,

Implementation of this alternative is not expected to be a problem. The technology is readily available,
conventional, and well demonstrated. Construction is straight forward and no unusual features are
anticipated to be required for the system. Coordination between U.S. EPA, MDPH. MDNR and the City
of Clare will be required to accomplish implementation of this ~lternative.
Capital Cost:
Annual 0 & M:
30 Year Present Worth:
$ 346,000
61,000
$ 1,284,059
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
In order to determine the most appropriate alternative for the Clare Water Supply site, the alternatives were
evaluated against each other. Comparisons were based on the nine evaluation criteria outlined below.
1 .
Overall Protection of Human Health and the Environment addresses whether
a remedy adequately protects human health and the environment and whether risks are
properly eliminated. reduced, or controlled throughl treatment. engineering controls. or
institutional. controls.
2.
Compliance with Applicable or Relevant and Appropriate Requirements
addresses whether a remedy meets all state and federal laws and requirements that apply
to site conditions and cleanup options.
5

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Figure 2: Site Detail Map

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3.
Long- Term Effectiveness and Permanence refers to the ability of a remedy to
reliably protect human health and the environment over time once cleanup goals have
been met.
4.
Reduction of Toxicity, Mobility, or Volume are three principal measures of the
overall performance of an alternative. The 1986 Superfund Amendments and
Reauthorization Act (SARA) emphasizes that whenever possible. the U.S. EPA should
select a remedy that will permanently reduce the level of toxicity of the contaminants at
the site, the spread of contaminants away from the Site. and the volume, or amount. of
contaminants at the site. ' .
5.
Short- Term Effectiveness refers to the likelihood of any adverse impacts to human
health or the environment that may be posed during the construction and implementation
period until cleanup goals are achieved.
6.
Implementability is the technical and administrative feasibility of a remedy. including
the availability of materials and services needed to implement the remedy.
7.
Cost includes capital, annual operation. and Total Present Worth costs of implementing a
remedy.
8.
State Acceptance indicates whether, based on its review of the initial data
submissions by the PRPs and Proposed Plan, the State of Michigan (MDNR) concurs
with, opposes, or has no comment on the alternative the U.S. EPA is proposing as the
preferred response technology for the site.
9.
Community Acceptance indicates whether the public concurs with the remedy
presented in the U.S. EPA's proposed plan.
. The No Action alternative is not protective of human health and, and there is a potential that Federal and
State drinking water ARARs will not be met. For these reasons. it is not available for selection and will not
be carried through the analysis against the nine criteria described above. The following is a discussion of
each of the criteria and alternative #2's performance against each of these. As an operable unit,
comparative analysis against the nine criteria will be limited to criteria relevant to this interim remedial action.
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT -- Threats to
public health would be eliminated for those residents receiving water from the public water system.
Exposure to organic contaminants would be reduced during the time it takes to determine the final
cleanup solution for the source areas at the Clare Water Supply.
COMPLIANCE WITH ARARs -- The State and Federal drinking water standards could be met in the
short term due to water treatment by the air strippers prior to distribution. Technology-based limitations
can be met by the air stripping alternative. Air Emission Requirements and Sewer Pretreatment
Requirements are other action-specific ARARs which can be met by the air stripping alternative. Vapor
phase carbon absorption may be required if contaminant cQ.Qcentrations in the inlet stream increase
significantly. The Michigan Department of Public Health is reituiring a permit for construction of the air
stripper. CE~.~LA exempts on-site actions from permit requirements.but the State wi'J.review all plans.

~ -- ~stimated capital costs for the air stripping alternative total $346,000.00. Major capital cost
items for t'fm; alternative include the stripping tower, building to support tower, cleaning package, gas
chromatograph and pertinent operator training. Major operation and maintenance items include energy
costs. sampling and monitoring, analytical laboratory serVices, routine systems inspection, and
6

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maintenance and reporting. Total annual major operation and maintenance costs are estimated to be
$60,700. The 30 year present worth cost is equal to $1,284,059 using a 5% discount rate.
IMPLEMENTABILITY -~ The technologies and services used in Alternative #2 is conventional. The
required contractor services for the treatment system are available. Coordination between U.S. EPA,
MONR, MOPH, and the City of Clare, would be required for the alternative. Potential future actions would
be possible and effectiveness could easily be monitored with the air stripping alternative.
SHORT TERM EFFECTIVENESS -- The air stripper can be designed and installed within several
months and will reduce contaminant concentrations in the municipal system immediately upon startup.
Contaminants in the water would change into a vapor and be emitted from the air stripper into the
atmosphere.
The carcinogenic risk associated with living in close proximity to the proposed air stripper, inhalation doses
were calculated for the contaminants found to be present in MW #2 and MW #5. The long-term
carcinogenic risks resulting from the inhalation of air emissions from the proposed air stripper is calculated
to be 1.3 x 10-7. It has been determined that the vapor would contain such a low concentration of VOCs
that dispersion into the atmosphere would not present a significant risk to plant workers or nearby
residents.
Pumping rates were selected to represent the largest daily ~olume pumped in 1989. Air stripper removal
efficiencies were assumed to be 100%. Downwind concentrations were estimated for a residence located
250 feet south of the treatment plant (the lo~ation of the closest residence).

LONG. TERM EFFECTIVENESS AND PERMANENCE - Not applicable because this first phase I
cleanup action is designed to protect public health while any longer term cleanup measures are being'
determined. .
REDUCTION IN TOXICITY. MOBILITY AND VOLUME -- By air stripping the drinking water, the
volume of contaminants is reduced in the water supply. However, generally no reduction in toxicity,
mobility, or volume of waste or hazardous substances is achieved by the alternative. Such reduction of
toxicity, mobility, or volume is not cost-effective when compared with the effectiveness and relatively lower
cost of an air stripping system alone, versus a system which utilized granular activated carbon to control air
emissions, considering the relatively low levels of contaminants to be treated.
STATE ACCEPTANCE -- The State of Michigan agrees with the EPA's Interim Action Proposed Plan.
COMMUNITY ACCEPTANCE -- Specific comments were received during the public comment period
and at the public meeting for the proposed plan. These comments were generally in favor of the air
stripping alternative and are addressed further in the Responsiveness Summary.
SUMMARY OF COMPARISON
Under the No Action alternative, contaminants would continue to increase in the distribution system and
would be progressively more difficult to remove by the current blending and aeration measures being
taken by the City of Clare. The Federal MCLs would likely be exceeded, especially during times of peak
demand. For these reasons, the No Action alternative is not considered a viable option for the site.
SelecteQ Remedy - Alternative #2 . the Air Stripping alternative would provide for protection of public
health in a very short time frame and for a reasonable cost and is the preferred remedial alternative for this
interim action operable unit. '
7

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This interim action will not exacerbate the existing situation and it is consistent with the goals of the final
operable unit.
STATUTORY DETERMINATIONS
Under its legal authorities, 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 must cornply with ARARs under Federal and State environmental
laws, unless a statutory waiver is justified. The selected remedy must also be cost effective and utilize
permanent solutions and alternative treatment or resource recovery technologies to the maximum extent
practicable. Finally, the statute includes a preference for remedies that employ treatment that
permanently and significantly reduce the toxicity, mobility or volume of hazardous substances, pollutants
and contaminants. The following sections discuss how the selected remedy, where applicable. meets the
statutory requirements and preferences.
A.
Protection of Human Health and the Environment
The selected remedy provides for protection of human health by eliminating consumption of. and
exposure to, contaminated drinking water with the affected area. As a public water supply system, the
selected remedy is a proven and reliable method of providing a permanent and safe drinking water supply
through required treatment and monitoring. .
The remedial objective of this operable unit is protection of human health only. Protection of the J
environment will be achieved by future operable units that address contaminated groundwater and on-site.
sources of contamination. .
B.
Compliance with Aoolicable or Relevant and Appropriate Requirements (ARARs)
The selected remedy will comply with all identified Federal ARARs and more stringent State laws. The
RCRA Land Disposal Restrictions do not apply to this operable unit remedial action.
C.
Cost-Effectiveness
The selected remedy is cost-effective.
D.
Utilization of Permanent Solutions and Alternative Treatment TechnoloQies to the Maximum
Extent Practicable
U.S. EPA and the State of Michigan have determined that the selected remedy represents the maximum
extent to which permanent solutions can be utilized in the most cost effective manner to addrElss drinking
water contamination in the affected area. Of the alternatives that are protective of human health and the
environment and comply with ARARs, U.S. EPA and the State have determined that the selected remedy
provides the best balance of tradeoff in terms of short-term effectiveness, implementability, cost and
considering State and community acceptance. The criteria of long-term effectiveness and permanence
are not relevant in the analysis of this interim action.
This operable unit does not address the reduction in toxicity. mobility or volume achieved through
treatment or the statutory preference for treatment as a principal element of the selected remedy. Future
operable units will specifically address the remediation of on-site sources and contaminated soils and
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groundwater with respect to applicable statutory requirements.
E.
Preference for Treatment
Since the selected alternative only transfers the VOCs to the atmosphere, this operable unit does not
address the preference for treatment. Again, this statutory preference will be evaluated in future operable
units that specifically address contamination at the Site.
RESPONSIVENESS SUMMARY
Appended to this ROD is the Responsiveness Summary which present background information,
community involvement and categorizes the public comments received during the public comment period
and U.S. EPA's responses to the comments. .
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RESPONSIVENESS SUMMARY
CLARE WATER SUPPLY SITE
CLARE, MICHIGAN
I.
RESPONSIVENESS SUMMARY OVERVIEW
The U.S. Environmental Protection agency (EPA) held a public comment period from July 12, 1990,
through August 13,1990 for comments on the Proposed Plan for an Interim Action Operable Unit at the
Clare Water Supply Site in Clare, Michigan (Site).
The Proposed Plan (PP) provides a summary of the background information leading up to the public
comment period. Specifically, the PP includes information pertaining to the history of the Clare Water
Supply Site, the scope of the proposed cleanup action and its role in the overall Site cleanup, the risks
presented by the Site, descriptions of the remedial alternatives evaluated by EPA, the identification of
EPA's preferred alternative, the rationale behind EPA's preferred altemative. and the community's role in
the remedy selection process.
EPA held a public meeting at 7:00 p.m. on July 18, 1990 at the Clare City Hall in Clare. Michigan to outline
the interim remedial alternatives described in the PP and to present EPA's proposed remedial alternative
for controlling contamination of the Clare drinking water supply.

This responsiveness summary, required by the Superfund Law, provides a summary of citizens' ,
comments and concerns identified and received during the public comment period, and EPA's responses'
to those comments and concerns. All comments received by EPA during the public comment period will
be considered in EPA's final decision for selecting the remedial alternative for addressing contaminated
drinking water at the Clare Water Supply Site.
This responsiveness summary is organized into sections and appendices as described below:
I.
RESPONSIVENESS SUMMARY OVERVIEW. This section outlines the purposes of the
Public Comment period and the Responsiveness Summary.
II.
BACKGROUND ON COMMUNITY INVOLVEMENT AND CONCERNS. This section
provides a brief history of community concerns and interests regarding the Clare Water
Supply.
III.
SUMMARY OF MAJOR QUESTIONS AND COMMENTS RECEIVED DURING THE
PUBLIC COMMENT PERIOD AND EPA RESPONSES TO THESE COMMENTS. This
section summarizes the oral comments received by EPA at the July 18, 1990 public
meeting, and provides EPA's responses to these comments.
IV.
WRITTEN COMMENTS RECEIVED DURING THE PUBLIC COMMENT PERIOD AND EPA
RESPONSES TO THESE COMMENTS. This section contains the letter received by EPA
containing written comments, as well as EPA's written response to that letter.
II.
BACKGROUND ON COMMUNITY INVOLVEMENT AND CONCERNS
Local awareness of the Clare Water Supply Site is very high, due to the fact that any contamination of the
city's municipal water system directly affects the entire community. The city provides municipal water

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service to Clare's 3,300 residents as well as to the many businesses located in the community. During the
school year, system use increases, since many of the children attending Clare public schools
(approximately 1,450 in total) reside outside the city limits. During business hours, water use by
employees who wor1< in Crare but reside outside the city limits, increases water usage.
Past involvement from the general community has primarily been expressed through calls to local and
state officials. These calls, which have occurred since the problem was first identified in 1981-1982,
primarily related to concerns about the safety of drinking the municipal water and questions about
potential health effects associated with short and long-term exposure to Site contamination. Other
residents have contacted the water department to complain about unusual odors in their tap water and to
register other concerns about water quality and taste. One resident contacted a city official to express
concem that the municipal water contamination may have been the cause of her husband's cancer.
In an attempt to address some of these concerns, the city water department prepared an information
summary about the Site including available health data regarding long-term exposure to identified levels of
TCE and DCE. Nonetheless, community concern about this issue has remained high.
The greatest community involvement to date has been provided by the Clare Pure Water Task Force. The
task force is comprised of concerned community members, primarily local businessmen. Between 1982
and 1985 (prior to official formation of the task force), some members of this group began to meet
informally to explore issues regarding contamination at the Site and the Site's potential impact on their
community. On November 7, 1985, several city officials and members of this unofficial community group
went to Lansing to meet with Representative Sidney Ouwinga, an aide to State Senator John Engler, and.
Michigan Department of Public Heahh (MDPH) and Michigan Department of Natural Resources (MDNR) I
representatives. The purpose of the meeting was to express the community's concerns about the Site
and urge State and Federal officials to expedite Site cleanup. The city also inquired into the availability of ,
State or Federal funds for well replacements and were informed that no funds would be available for at .
least a year.
On July 2, 1986, the city was informed by Senator John Engler that a grant of $300,000 would be
provided to Clare through a special state legislative action (House Bill 5936). This grant enabled the city to
begin studies to identify a suitable location for the new well. Eventually, these efforts resuhed in the
construction of MW #7. A hydrogeological study was initiated on behalf of the city in August 1986 by
Groundwater Management Inc. and the Layne Northern Company.
According to MDPH and city officials, problems with ground water quality and supply in the Clare area
restricted potentially suitable locations for a new well. Historically, areas on the north side of Clare have
had poor ground water quality, due to high iron content and water hardness. In the northeastern sector,
low ground water flow impacted overall water capacity considerations. Septic disposal problems impacted
use of areas to the west of the city. Consequently, after investigating several alternative locations, the city
uhimately elected to site MW #7 in an area about 1,500 feet to the west of the current well field.
This decision was reportedly unpopular with many community members, including some task force
members who had originally urged construction of a new well in a area removed from the site
contamination. Community and city concern increased following release of a 1988 study prepared for the
city. This study indicated that pumpage of MW #7 would need to be confined to 200 gallons per minute
(GPM) for a 24-hour day, or 400 gpm for a 12-hour day, in order to avoid a cone of depression drawing
contaminated ground water towards the new well. The study indicated that even if pL!mpage of MW #7
were confined under this scenario (which could produce less water capacity than required by the city), site
contamination might still reach MW #7 within five years.
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Despite the findings of the study, the city has continued to support construction of the well in the
selected location. According to city officials, this decision is primarily due to water qualitylWater supply
problems with other potential sites and the lack of available funds to both continue siting studies and still
have sufficient monies to~onstruct a new production well. While city official are disappointed that a
suitable location could not be identified outside the contaminated site area, they are hopeful that the Site
can be cleaned up before contamination reaches the new well. However, many community members
reportedly remain opposed to this solution.
At the initial Remedial Investigation public meeting conducted by EPA in Clare in August 1988,
community members raised a number of concems which had been previously expressed to state and local
official. Among these were: the concern for pure water; concerns about potential Site-related health
effects to children and adults; frustration over continued Site investigations rather than prompt Site
cleanup; concern over contamination remaining in soils despite two major removal activities, and concern
that Site contamination will eventually contaminate the city's planned new well (MW #7) as well as impact
the city's use of this well and its ability to supply adequate water capacity. Other concerns by interested
parties at the public meeting included whether the PRPs will pay for a new production well for the city,
whether purging will be performed to clean up contamination in MW #2 and MW #5, and questions about
why EPA hasn't considered current contaminant levels in municipal water to pose an immediate threat to
public health.
Types of information requested included:
o
Clearer information regarding current levels of contaminants in the municipal water and known
associated health effects data.
o
Clarification regarding relevant regulatory standards.
o
Clarification of specific contaminants identified in municipal well water versus those identified in
soils and surface water around the Site.
o
Clarification regarding the roles and authorities of various agencies in the remedial process
(including EPA, MDNR, and MDPH). .
o
Time frames for planned RifFS activities.
o
Status reports on the progress of site work including analytical results of sampling and findings of
major phases of RifFS work.
ADMINISTRATIVE RECORD
As part of EPA's responsibility and commitment to the Superfund Program, the community has been kept
informed of ongoing activities conducted at the Clare Water Supply Site. EPA has established information
repositories where relevant Site documents may be reviewed at the Garfield Memorial Library at 4th and
McEwan Streets in Clare, Michigan. Documents stored at the repositories include:
o
Proposed Plan for Wellhead Protection.
o
Analytical Data upon which this Decision is based.
o
Fact sheets, summarizing the technical studies conducted at the Site.
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o
Public Meeting Transcript.
Alternatives Array for 2nd Operable Unit.
o
EPA's selection of a remedy to control drinking water contamination at the Site is presented in a document
known as a Record of Decision (ROD). The ROD and the documents containing information which EPA
used in making its decision (except for documents that are published and generally available) will also be
placed in the information repositories, as will this responsiveness summary.
III.
COMMENTS RECEIVED DURING THE PUBLIC COMMENT PERIOD AND EPA
RESPONSES TO THESE COMMENTS.
A Public Meeting regarding the Interim Action took place on July 18, 1990. At this meeting, the public was
updated on the status of the on-going Remedial Investigation/Feasibility Study (RifFS), the current and
potential site risks, the alternatives which had been considered for addressing the potentially
contaminated drinking water supply, and the EPA and MDNR preferred remedial alternative of Packed
Tower Aeration of the drinking water from municipal wells (MW) #2 and MW #5. Questions and concems
were expressed by the Citizens of Clare at the public meeting.
U.S. EPA and MDNR responded to these questions and concerns during the July 18, 1990 public
meeting. These questions and the U.S. EPA's and MDNR's responses can be found in the public
meeting transcript, which is part of the Administrative Record for the Clare Water Supply Site.
,
Comments offered during the FORMAL COMMENT PORTION of the Public Meeting included:
Mr. Brad Brogren of the Michigan Department of Public Health expressed the following comments --
They have been sampling the Clare Water Supply on a quarterly basis for the last 8 years and have over
100 samples. Even though these samples generally back up what the EPA is trying to say - the Clare
Water Supply has not been over the MCL for 4 times during the year which is the requirement. MDPH
generally feel that a new well should be installed but in this case agrees that that would not be feasible.
MDPH accepts the proposed plan for air stripping at the Clare Site, will review construction plans, issue
construction permits, and ensure the proper operation and maintenance of the air stripping system.
Mr. Patrick Boyle expressed his acceptance of the plan and stated his preference that the PRPs pay
the costs of operation and maintenance of the air stripper system. Response to Mr. Boyle - The
U.S. EPA is pursuing a settlement with the PRPs which will include their payment of all Operation and
Maintenance costs.
IV.
WRITTEN COMMENTS RECEIVED DURING THE PUBLIC COMMENT PERIOD.
Jody McDaniel of Clare filed the only written comment during the comment period. Therein she
expressed that she is very anxious to see the air stripping system implemented and expressed her
concern over the present quality of Clare drinking water.
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