United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R01-91/055
April 1991
&EPA Superfund
Record of Decision:
-------
REPORT DOCUMENTAnON 1'. REPORTNO. 1 ~ I. A8cIpIenI'8 ~on No.
PAGE EPA/ROD/R01-91/0SS
1118 end SIM1I8 5. Report Dete
3UPERFUND RECORD OF DECISION 04/16/91
Western Sand & Gravel, RI
I.
Third Remedial Action
7. Aulhor(8) .. Pwfonnlng OrganIzation Rapt. No.
8. JI8rfonnlng Orll8lnlza1lon ..... end AddI88 10. PtoJectlTuklWOItt Unit No.
11. ConII8cI(C) or Clr8nt(G) No.
(C)
(0)
12. ~ OrgeNDllon"'" end AddI88 11. Type of R':I*' & Pettocl Coveted
U.S. Environmental Protection Agency
401 M Street, S.W. 800/000
Washington, D.C. 20460 14.
15. SUppIemenI8ry No...
11. Abene! (LImI1: 200 wonIe)
The 20-acre Western Sand & Gravel site is a former liquid waste disposal site on the
boundary of Burrillville and North Smithfield, Rhode Island. Land use in the area is
primarily semi-rural. Tarklin Brook, which lies within a wetland immediately to the
west of the disposal area, discharges to a reservoir north of the site. Residential
areas to the west and north of the site have private wells and use treated ground water
as a source of drinking water. From 1975 to 1979, approximately 12 acres of the site
~ere used for the disposal of liquid wastes including hazardous substances and sewage.
These wastes. were dumped into 12 unlined lagoons and pits, and subsequently infiltrated
through the porous soil and into the ground water. As a result of a fire in one of the
pits in 1977, local officials ordered the owner to remove chemicals from the site.
After the owner failed to comply, a Cease and Desist Order was issued in 1979, and
wastes were no longer accepted. In 1980 at the request of the State, EPA removed
approximately 60,000 gallons of VOC-contaminated liquid wastes from the lagoons. In
1982, the State began a ground water recirculation system to control the spread of
contaminants in the ground water. Remedial activities for the site have been divided
into three operable units (OUs), addressed by three Records of Decision (RODs). A 1984
(See Attached Page)
17. Docun8nt An8Jy8I8 L D88crtptol8
Record of Decision - Western Sand & Gravel, RI
Third Remedial Action
Contaminated Medium: gw
Key Contaminants: VOCs (benzene, PCE, TCE, toluene, vinyl chloride, xylenes), other
organics, metals (arsenic, chromium, le~d)
b. Identltl8n/Qp8n-EndId T-
Co COSAl1 ~
18. An08bIIty SI8I8m8nt 11. S8curity CIa8 (ThI8 Report) 21. No. of P8ge.
. None 251
~ 211. S8a8tty CIa8 (ThI8 Page) ~ Prtce
Nonp-
80272-101
G
(S88 ANSI-Z38.18)
s..~_onllt-
(F0I'III8IIy NTlS-35)
-------
EPA/ROD/ROl-91/055
Western Sand & Gravel, RI
~bird Remedial Action
.~stract (Continued)
ROD provided for installation of water filters in affected residences, and subsequent
provision for a permanent alternate water supply (OU1). A 1985 ROD addressed OU2,
which provided site closure activities, including capping contaminated soil areas with
a RCRA-approved cap, phaseout of the ground water recirculation system, and removal and
offsite disposal of the associated equipment, evaluation of alternatives for ground
water treatment, ground water monitoring, and implementing site access restrictions
such as fencing. This ROD addre~ses contaminated ground water, which discharges into
Tarklin Brook and the reservoir as OU3. The primary contaminants of concern affecting
the ground water are VOCs including benzene, PCE, TCE, toluene, vinyl chloride, and
xylenes; other organics; and metals including arsenic, chromium, and lead.
~
The selected remedial action for this site includes natural attenuation of ground
water; implementing a site monitoring program for sediment, ground water, and surface
water; and implementing institutional controls to restrict consumption of ground water.-
A comparison of current and historical data indicates that the magnitude and extent of
contamination has decreased significantly and will continue to decrease with time as
the integrity of the cap is maintained. Ground water is expected to achieve interim
cleanup levels within 24 to 28 years. However, if this cleanup is proceeding at an
unacceptable rate, active restoration including pumping and treatment by sedimentation,
filtration, air stripping, and carbon adsorption, followed by onsite discharge to
Tarklin Brook will be implemented as a contingency remedy. There are three additional
scenarios that individually may trigger active restoration. These include: determining
that Tarklin Brook is endangered, that a threat exists from contamination of the
"~drock, or that institutional controls cannot be implemented effectively. The
;imated present worth cost for this remedial action is $1,123,952 ($4,039,227 with
active restoration), which includes an annual O&M cost of $1,041,452 ($2,990,151 with
active restoration) for 24 to 28 years.
PERFORMANCE STANDARDS OR GOALS: Interim ground water cleanup goals are based on SDWA
MCLs and MCLGs, a 10-6 excess cancer risk level and an HI=l, or practical
quantification limits. Once all ARAR-based interim levels have been achieved, a risk
analysis will be performed to develop a cumulative risk assessment. The cumulative
risk of residual levels must attain a 10-4 to 10-6 risk range for carcinogens and HI=1
for non-carcinogens before these levels will be considered as the final cleanup levels
for any action. Chemical-specific interim goals for ground water include benzene 5
ug/l (MCL), PCE 5 ug/l (MCL), TCE 5 ug/l (MCL), toluene 1 mg/l (MCL), vinyl chloride 2
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.
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION I
J.F. KENNEDY FEDERAL BUILDING, BOSTON, MA 02203-2211
DATE:
MEMORANDUM
SUBJ:
FROM:
v
TO:
April 25, 1991
ROD Signing ~fi
Pat Beland ~ J
Region I ROD Coo~ nator
Irene Johnson
Hazardous Site Control Division (OS-220)
Attached is a hard copy with diskette of the signed Record of
Decision (ROD) for the following site:
SITE:
WESTERN SAND , GRAVEL SITE
LOCATION:
BURRILLVILLE , NORTH SMITHFIELD, RI
DATE SIGNED:
APRIL 16, 1991
If you have any questions, please call me at FTS 833-1610.
Attachment
. -
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~ 87'..~.
(Sl'
(. 0fII(ftf.(.~
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION I
J.F. KENNEDY FEDERAL BUILDING, BOSTON, MASSACHUSETTS 02203-2211
u.s.
ENVIRONMENTAL PROTECTION AGENCY
REGION I
<.;
RECORD OF DECISION
WESTERN SAND , GRAVEL SITE
BURRILLVILLE AND NORTH SMITHFIELD, RHODE ISLAND
.,
Bt.&.T009~
~ .
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.. ..
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"311. ~
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.
.;t.O 8T..~
(ei)
~;!
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION I
J.F. KENNEDY FEDERAL BUILDING. BOSTON. MASSACHUSETTS 02203-2211
.-
DECLARATION FOR THE RECORD OF DECISION
Western Sand & Gravel Superfund site
Burrillville and North Smithfield, Rhode Island
. STATEMENT OF PURPOSE
q
This Decision Document presents the selected remedial action for
the Western Sand & Gravel Superfund site .in Burrillvilleand
North Smithfield, Rhode Island, 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), the National oil and
Hazardous Substances contingency Plan (NCP), and 40 CFR Part 300
et sea., as amended. The Region I Administrator has been
delegated the authority to approve this Record of Decision (ROD).
The State of Rhode Island does not concur with the selected
remedy.
STATEMENT OF BASIS
This decision is based on the Administrative Record which has
been developed in accordance with section 113(k) of CERCLA and
which is available for public review at the Burrillville Town
Building, 105 Harrisville Main street, Harrisville, Rhode Island,
and at the Region I Waste Management Division Records Center at
90 Canal Street, Boston, Massachusetts. The Administrative
Record Index (Appendix F to the ROD) identifies the items which
comprise the Administrative Record upon which the selection of
the remedial action is based. .
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 ROD, may present an imminent and substantial
endangerment to the public health or welfare or to the
environment.
DESCRIPTION OP THE SELECTED REMEDY
This remedy is the third remedy selected for the site. The
remedies selected in 1984 and 1985 and implemented in 1988, 1989
and 1990 reduced the immediate risk posed by the groundwater
contamination and reduced the source of contamination. This
remedy addresses the potential future risks caused by the
groundwater contamination remaining at the site.
8,,510-9..-
, .
'" '"
-' ..
<> ~
~ ..
"'3tJ.~
-------
.
2
The remedial measures to address the groundwater contamination
include:
.
Reliance on natural attenuation of contaminated groundwater
witn contingent active restoration. Natural attenuation
will lower contaminant concentrations through physical,
chemical and biological processes until groundwater interim
cleanup levels are met. According to hydrogeologic
groundwater models, groundwater is expected to be restored
to the interim cleanup levels in approximately 24 to 28
years. If the groundwater is not restored at the rate.
predicted by modeling or faster, active restoration shall be
utilized to restore the groundwater. Groundwater monitoring
data shall be evaluated every three years for the first nine
years, and every five years thereafter to determine if
natural attenuation is restoring the contaminated
groundwater at the rate predicted by modeling or faster.
utilization of institutional controls to reduce the risk to
public health from consumption of the groundwater. Such
controls may include regulatory restrictions, acquisition of .
affected properties or groundwater rights, and other
restrictions on property transactions. Institutional
controls shall be imposed in the area where the risk to
public health is outside EPA's acceptable risk range. In
addition, this area also includes a buffer zone which allows
for a residential well to be installed without drawing
contaminated groundwater from the area which poses an
unacceptable risk. This buffer zone is equal to 300 feet at
this Site.
o
.
.
Implementation of a site monitoring program that shall
include, at a minimum, long-term monitoring of the
overburden groundwater. In addition, the site monitoring
program may include long-term monitoring of the bedrock
system, the surface water, and the sediments. The
groundwater monitoring program shall operate until the
groundwater is restored which is predicted by modeling to
occur within 24 to 28 years.
In addition to requiring active restoration if natural
attenuation is not restoring the groundwater at a rate predicted
by modeling or faster, there are three other scenarios which
trigger active restoration. First, the selected remedy also
requires active restoration of theg=oundwater and/or long-term
monitoring of the surface water and sediments if necessary to
prote~t Tarkiln Brook. Second, based on a review of the new
information collected to characterize bedrock impacts, active
restoration and/or long-term monitoring may be implemented if
necessary for the protection of public health and the
environment. Finally, if effective institutional controls cannot
be implemented, the selected remedy utilizes active restoration
-------
.
3
DECLARATION-
'"
The selected re~edy is protective of the human health and the
environment, attains federal and state requirements that are
applica~le or relevant and appropriate for this remedial action,
and is cost-effective. If natural attenuation restores the
groundwater to the interim cleanup levels effectively, there is
no reduction of toxicity, mobility or volume through treatment
for this alternative. However, if the groundwater is not
restored at the rate predicted by modeling or faster, the
selected remedy utilizes active restoration to achieve the
necessary reductions of toxicity, mobility and volume.
Therefore, the selected remedy utilizes treatment to reduce
toxicity, mobility or volume to the extent necessary. In
addition, this remedy utilizes permanent solutions and
alternative treatment technologies to the maximum extent
practicable.
~ ", /111
Date
---
Julie Belaga .
Regional Administrator
u.s. EPA, Region I
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V.
VI.
ROD DECISION SUMMARY
WESTERN SAND , GRAVEL SITE
TABLE OF CONTENTS
Contents
paae Number
I.
-
SITE NAME, LOCATION AND DESCRIPTION
.......
. . .
II.
SITE HISTORY AND ENFORCEMENT ACTIVITIES. . . . . . . .
A. Land Use and Response History. . . . . . . . . . .
B. Enforcement History. . . . . . . . . . . . . . . .
III. COMMUNITY PARTICIPATION
. . . .
. . .
. . .
. . .
. . .
IV.
SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION
. . .
SUMMARY OF SITE CHARACTERISTICS. . . . . . . . . . . .
A. Overburden Groundwater. . . . . . . . . . . . . .
B. Bedrock Groundwater. . . . . . . . . . . . . . . .
C. Residential Wells. . . . . . . . . . . . . . . . .
D. Surface Water and Sediments. . . . . . . . . . . .
SUMMARY OF SITE RISKS. . . . . . . . . . . . . . . . .
A. Exposure Pathways. . . . . . . . . . . . . . . . .
1. Residential use of groundwater. . . . . . . .
2. Recreational use of surface water and
sediments. . . . . . . . . . . . . . . . . .
Characterization. . . . . . . . . . . . . . .
Residential Use of Groundwater. . . . . . . .
Recreational use of surface water and
sediments. . . . . . . . . . . . . . . . . .
Uncertainties and Conclusions of Public Health
Assessment. . . . . . . . . . . . . . . . . . . .
Environmental Risk Assessment. . . . . . . . . . .
B.
Risk
1.
2.
c.
D.
VII. DEVELOPMENT AND SCREENING OF ALTERNATIVES. . . . . . .
A. Statutory Requirements/Response Objectives. . . .
B. Technology and Alternative Development and
Screening. . . . . . . . . . . . . . . . . . . . .
VIII. DESCRIPTION OF ALTERNATIVES. . . . . . . . . . . . .
A. Alternatives developed by Hunt. . . . . . . . . .
Alternative 1 (No Action) ~ . . . . . . . . . . . .
Al terna t i ve 2 . . . . . . . . . . . . . . . . . . .
Al terna t i ve 3 . . . . . . . . . . . . . . . . . . .
Al ternati ve 4 . . . . . . . . . . . . . . . . . . .
Alternative 5 . . . . . . . . . . . . . . . . . . .
Alternative 6 (Developed by EPA) .........
A1 ternati ve 6 . . . . . . . . . . . . . . . . . . .
B.
i
.
1
1
1
4
<>
5
-'
6
7
"7
8
10
10
11.
12
12
13
13
14
16
17
18
19
19
20
21
21
21.
22
22
23
25
25
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STATUTORY DETERMINATIONS. . . . . . . . . . . . . . . .
A. The Selected Remedy is Protective of Human Health
and the Environment. . . . . . . . . . . . . . . .
The Selected Remedy Attains ARARs . . . . . . . . .
The Selected Remedial Action is cost-Effective
The Selected Remedy utilizes Permanent Solutions
and Alternative Treatment or Resource Recovery
Technologies to the Maximum Extent Practicable
The Selected Remedy does n~t Satisfy the
Preference for Treatment which Permanently and
Significantly reduces the Toxicity, Mobility or
Volume of the Hazardous Substances as a Principal
Element. . . . . . . . . . . . . . . . . . . . . .
Contents
IX.
'-'
X.
XI.
B.
C.
D.
E.
ROD DECISION SUMMARY
WESTERN SAND , GRAVEL SITE
TABLE OF CONTENTS
Paqe Number
SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
1: Overall protection of human health and the
environment. . . . . . . . . . . . . . . . . . . .
Compliance with ARARs . . . . . . . . . . . . . . .
Lona-term Effectiveness and Permanence. . . . . .
Reduction of Toxicitv. Mobilitv. or Volume throuah
treatment. . . . . . . . . . . . . . . . . . . . .
Short-term Effectiveness. . . . . . . . . . . . .
Implementabilitv . . . . . . . . . . . . . . . . .
Cost. . . . . . . . . . . . . . . . . . . . . . .
state Acceptance. . . . . . . . . . . . . . . . .
Communi tv Acceptance. . . . . . . . . . . . . . .
2.
3.
4.
5.
6.
7.
8.
9.
THE SELECTED REMEDY. . . . . . . . . . . . . . . . . .
A. Interim Cleanup Levels. . . . . . . . . . . . . .
B. Description of Remedial Components. . . . . . . .
1. Restoration of contaminated groundwater by
natural attenuation with contingent active
restoration. . . . . . . . . . . . . . . . .
Institutional controls for potential future
residences. . . . . . . . . . . . . . . . . .
Site monitoring. . . . . . . . . . . . . . .
2.
3.
XII. DOCUMENTATION OF SIGNIFICANT CHANGES. . . . . . . . . .
A. Institutional Controls. . . . . . . . . . . . . .
B. Modified Approach to Evaluation of Natural
Attenuation. . . . . . . . . . . . . . . . . . . .
XIII.
STATE ROLE. . . . . . .. . . . .
...........
ii
27
29
30
32
33
33
34
35
36
36
37
37
39
39
41
42
44
44
46
47
48
50
50
51
51
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.
ROD DECISION SUMMARY
WESTERN SAND , GRAVEL SITE
TABLE OF CONTENTS
APPENDICES
APPENDI~ A - FIGURES
APPENDIX B - TABLES
APPENDIX C - RESPONSIVENESS SUMMARY
APPENDIX D - EXAMPLE OF EVALUATION OF NATURAL ATTENUATION
APPENDIX E - STATE OF RHODE ISLAND NONCONCURRENCE LETTER
APPENDIX F - ADMINISTRATIVE RECORD INDEX
~
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.
ROO DECISION SUMMARY
Western Sand' Gravel site
Page 1
I.
SITE NAME, LOCATION AND DESCRIPTION
The Western Sand & Gravel (WS&G) Site (the site), is located on
Douglas Pike, also known as Route 7, on the boundary of
Burrillville and North Smithfield, Rhode Island (Appendix A,
Figure 1). Prior to 1975, the Site were used for a gravel mining
operation. Beginning in 1975 and continuing until April 1979,
approximately twelve (12) acres of the Site had been used for the
- disposal of liquid wastes, including hazardous substances and
sewage waste. These wastes- were dumped into twelve (12) unlined
lagoons and pits at the site. The wastes subsequently
infiltrated through the porous soils and contaminated the
groundwater.
"
The area surrounding the Site is primarily semi-rural. Tarkiln
Brook is located immediately to the west of the disposal area.
Tarkiln Brook flows north and discharges into the Slatersville
Reservoir (Appendix A, Figure 2). Tarkiln Brook and the
Slatersville Reservoir are Class B water bodies according to
Rhode Island Water Quality Standards, suitable for fishing,
swimming and other recreational purposes. A wetland area borders
Tarkiln Brook. To the east of the site is an area used for sand
and gravel mining. To the south of the site is a sand and gravel-
processing operation owned by Western Sand & Gravel, Inc., which
is bounded on the southern property line by Douglas Pike (Route
7) .
A residential area is located to the west and north of the site.
There are several homes near the site that currently have private
wells and use treated groundwater as a source of drinking water.
These homes are located on Douglas Pike, Pulaski Road and other
nearby roads. These shall be connected to a permanent alternate
water supply in the near future. The nearest residences are
approximately 1000 feet northwest of the disposal area. The site
is also located over the Slatersville Aquifer which has been
designated as a drinking water source by the State of Rhode
Island.
A more complete description of the site can be found in the
"Groundwater Remedial Investigation, Western Sand & Gravel Site,
Burrillville, ~ode Island," June, 1990, in section 1.0 of Volume
1.
II.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
A.
Land Use and Response History
The Site, owned by Western Sand & Gravel, Inc., was a sand and
gravel quarry operation from 1953 until 1975. Beginning around
1975, approximately twelve (12) acres of the twenty (20) acre
parcel were used for the disposal of liquid wastes, including
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.
ROD DECISION SUMMARY
Western Sand & Gravel Site
Page 2
twelve (12) unlined lagoons and pits. A fire occurred in one of
the chemical-pits in March 1977, and Fire Department officials
from Burrillville and North smithfield ordered Mr. James Cardi,
Jr., the Site owner and operator, to remove the chemicals from
the Si~e. Mr. Cardi responded by burying the contents of the
waste pit. On April 24, 1979, a Cease and Desist Order was
issued to Mr. Cardi by the Rhode Island Department of
Environmental Management (RIDEM) for violations of water and air
pollution regulations. After April 1979, wastes were no longer
accepted at the Site. RIDEM.Tecords indicate that about 470,000
gallons of waste were deposited at the Site during its last year
of operation.
In March 1980, at the request of RIDEM, EPA began a removal of
the hazardous liquid still remaining in the lagoons. It is
estimated that approximately 60,000 gallons of liquids were
pumped and removed from the lagoons. These actions were taken
under the authority of Section 311 of the Clean Water Act and
were completed in the fall of 1980, prior to the passage of the
Comprehensive, Environmental Response, Compensation and Liability
Act (CERCLA). Analysis of these wastes showed that they
contained high levels of volatile organic compounds (VOCs). In
October 1981, EPA proposed the addition of the Site to the
National Priorities List (NPL) making it eligible to receive
Superfund monies for investigation. The Site was thereafter
finalized on the NPL in September 1983. In 1982, RIDEM took the
lead responsibility for the activities at the Site and began a
groundwater recirculation system in an effort to control the
spread of contaminants in the groundwater. In May 1984, RIDEM
completed the first Remedial Investigation and Feasibility Study
(RIfFS) for the site under a cooperative agreement with EPA. The
conclusions of the RI were as follows:
.
Organic chemicals have infiltrated through highly
permeable soil into groundwater;
.
Some private drinking water wells show low levels of
contamination;
.
Contaminated groundwater has discharged into nearby
Tarkiln Brook and Slatersville Reservoir;
.
Organic chemicals have migrated from the site through
the upper fractured bedrock and have contaminated
residential wells downgradient from the Site;
.
Contaminated soil and sludges exist in various
locations on the site; and,
.
There is no indication of hazardous air. emissions.
In September 1984, EPA issued the first Record of Decision (ROD)
-------
ROD DECISION SUMMARY
Western Sand' Gravel site
Page -3
.
Install of water filters as an Initial Remedial Measure
.iIRM) to provide protection for homes with contaminants
identified in their wells, until the permanent
alternate water supply is functional; and,
Install of a permanent alternate water supply to
service approximately 56 parcels of land.
starting in August 1984, Olin Hunt Specialty Products, Inc.
(Hunt), a potentially responsible party at the Site, installed
water filters in private homes with contaminated wells and in
homes with wells that might become contaminated. EPA began
construction of the permanent water supply in April 1990. The
u.S. Army Corps of Engineers has indicated that the permanent
alternate water supply is certifiably complete and operational.
<>
.-
EPA conducted additional investigations in 1984 and 1985 which
concluded with the preparation of an Addendum to the 1984 RIfFS
Report developed by RIDEM. Following the finalization of the
Addendum in August 1985, EPA issued a second ROD in september
1985 which required the following:
.
Grade contaminated soil to the cap area;
Install an impermeable cap consistent with RCRA
provisions;
.
.
Phase-out the operation of the groundwater
recirculation system, and remove and dispose of the
associated equipment;
.
Grade, loam and seed the cap and the surrounding Site
surface;
.
Fence and post the site;
. Provide inspection and maintenance of the cap, fence
and postings consistent with RCRA provisions; .
.
.
Conduct groundwater monitoring consistent with RCRA
post-closure provisions; and,
.
Conduct a RIfFS to characterize the extent of the
groundwater contamination and to develop and evaluate
alternatives for groundwater remediation.
Pursuant to a consent decree among the EPA, the State of Rhode
Island and Hunt, construction activities for the impermeable cap
were completed by Hunt in 1987. All contaminated soils were
graded to the cap site and an impermeable cap, of approximately
two (2) acres, was installed and now covers the contaminated
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.
. ROD DECISION SUMMARY
. Western Sand & Gravel site
Page 4
warning si~ns and comprise approximately six (6) acres. Post
closure moni~oring and inspections of the cap and graded site
area are ongoing.
Also p~suant to the consent decree, Hunt initiated the
Groundwater Remedial Investigation and Feasibility study in 1988.
Hunt submitted the Draft Groundwater RI Report for the Site on
February 26, 1990. In a letter dated March 30, 1990, EPA
submitted comments on the document. In letters dated April 9,
1990 and May 3, 1990, RIDEM submitted comments on the document on
behalf of the state of Rhode Island."On June 22,1990, Hunt
submitted a Revised Groundwater RI Report and responses to EPA's
andRIDEM's comments. In letters dated July 24, 1990 and
September 10, 1990, RIDEM identified deficiencies in Hunt's
responses to RIDEM's comments. EPA also commented in a letters
dated October ,25, 1990 and October 31, 1990 on Hunt's analysis of
the data and the conclusions presented in the report. In
November 1990, EPA generated an Addendum to the report to present
the major findings of the RI and the remedial action objectives
for the Site as determined by EPA based on the data collected by
Hunt and presented in the Revised Groundwater RI Report (June
1990).
Hunt submitted the Draft Groundwater FS Report for the site on
May 8, 1990. In a letter dated June 13, 1990, EPA submitted
comments on the. document. In a letter dated June 14, 1990, the
RIDEM submitted comments on the document on behalf of the State
of Rhode Island. In letters dated October 12, 1990 and October
22, 1990, H~nt submitted a Revised FS Report and responses to
EPA's and RIDEM's comments. In a letter dated January 14, 1991,
EPA submitted comments to Hunton the Revised Groundwater FS
Report. EPA's comments focused on the detailed analysis, Section
4 of the report. EPA also generated an Addendum to that report
to address EPA's comments on the Revised FS Report developed by
Hunt. Specifically, the addendum contains a detailed analysis of
the alternatives developed by Hunt in the Revised Groundwater FS
Report and a new alternative developed by EPA.
A more detailed chronology of the Site history can be found in
Appendix A of the Revised Groundwater RI Report (June 1990)
developed by Hunt.
B.
Enforcement History
In February 1982, EPA notified approximately eight (8) parties
who either owned or operated the facility, generated wastes that
wer~ shipped to the facility, arranged for the disposal of wastes
at the facility, or transported wastes to the facility of their
potential liability with respect to the Site. Negotiations
commenced with these potentially responsible parties (PRPs) in
early 1982 regarding the settlement of the PRP's liability at the
site. These early negotiations did not result in any settlements
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ROD DECISION SUMMARY
, Western Sand & Gravel site
.
Page 5
~
In late 1983, EPA notified approximately ninety one (91) parties
of their potential liability. On February 7, 1984, a meeting
attended by forty nine (49) of the ninety one (91) PRPs was held.
in Boston, MA to begin negotiations in order to determine whether
any responsible party was willing and able to undertake the
remedial design/remedial action (RD/RA) for the first Record of
. Decision (ROD). The PRPs formed a steering committee and
substantial negotiations between EPA and the PRPs were conducted.
To date, these negotiations resulted in a settlement concerning
the Site in late 1986 with approximately forty five (45) parties.
The settlement covered the activities described by the two RODs
that had been issued as of. that time. The consent decree for the
settlement became effective on June 3, 19.87. Pursuant to the
consent decree, the settling parties have: paid for past costs
expended by EPA and RIDEM as of the settlement; paid for the
costs of future oversight by EPA and RIDEM related to the first
two RODs; implemented the interim water filter program; paid for
the construction and operation of the permanent water supply
system; closed the Site consistent with the second ROD; and
undertaken the RI/FS for groundwater contamination, although
final approval of RI/FS activities has not been granted.
Additional work relating to the bedrock characterization, and
additional surface water and sediment monitoring is still
necessary.
The PRPs have been active in the remedy selection process for the
groundwater contamination at the site. EPA mailed a copy of the
proposed plan 'for the groundwater contamination to the PRPs in
February 1991. Technical comments presented by PRPs during the
public comment period are included in the Administrative Record.
A summary of these comments as well as EPA's responses, which
describe how these comments affected the remedy selection, are
included in the Responsiveness Summary, Appendix C of this
document. EPA .expects that special notice for this remedy will
be issued in April 1991.
III. COMMUNITY PARTICIPATION
Throughout the site's early history, community concern and
involvement had been moderate to high. In 1978, local citizens
,formed a group called Protect Our Water (POW) in response to the
potential hazards posed by the Western Sand & Gravel site and
other sites in the area. In 1979, the Town Councils of
Burrillville and North smithfield also held joint meetings to
discuss the problems caused by the site. In December 1982, the
Western Sand & Gravel Coordinating Committee was formed by the
Burrillville Town Council to facilitate communications on matters
involving the Site.
EPA has kept the community and other interested parties apprised
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. ROD DECISION SUMMARY
Western Sand' Gravel Site
page 6
sheets, press releases and public meetings. EPA's public
meetings on the first ROD in 1984 was attended by between 50 and
100 persons. The 1985 public meetings on the second ROD,
however, was at~ended by only 10 to 20 attendees. The
Coordin~ting Committee was never officially disbanded, but has
not been active for almost five (5) years. In general, community
interest and awareness now is relatively low compared to the
activity that took place during the initial site investigation
phases.
In September 1982, RIDEM issued the first community relations
plan for the Site. In November 1990, EPA released a revised
community relations plan which outlined a program to address
community concerns and keep citizens informed about and involved
in activities during remedial activities. Also in November 1990,
EPA released a fact sheet to describe the results of the Remedial
Investigation.
On October 25, 1990, EPA made the administrative record available
for public review at EPA's offices in Boston and at the
Burrillville Town Building, 105 Harrisville Main Street,
Harrisville, Rhode Island. EPA published a notice and brief
analysis of the Proposed Plan in the Woonsocket Call on February
4, 1991 and made the plan available to the public at the
Burrillville Town Building.
On February 11, 1991, EPA held an informational meeting to
discuss the results of the Remedial Investigation and the cleanup
alternatives presented in the Feasibility Study and to present
the Agency's Proposed Plan. Also during this meeting, the Agency
answered questions from the public. From February 12, 1991 to
March 13, 1991, the Agency held a thirty (30) day public comment
period to accept public comment on the alternatives presented in
the Feasibility Study and the Proposed Plan and on any other
documents previously released to the public. On February 28,
1991, the Agency held a public hearing to discuss the Proposed
Plan and to accept any oral comments. A transcript of this
hearing and the comments and the Agency's response to comments
are included in the Responsiveness Summary in Appendix C.
IV.
SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION
The activities at the site have been divided into three operable
units. The first operable unit was defined by the first ROD
issued in 1984 and consisted of providing water filters for homes
with contaminated wells and in~talling the permanent alternate
water supply. The remedy in the 1984 ROD for the first operable
unit reduced the immediate risk to public health from exposure to
contaminated groundwater. The second operable unit was defined
by the second ROD issued in 1985 and consisted of site closure
activities. The remedy in the 1985 ROD for the second operable
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ROD DECISION SUMMARy
Western Sand' Gravel site
Page ~
contaminated soils remaining onsite and reduced the source of the
groundwater contamination. The third operable unit for the Site
addresses .the groundwater contamination. This remedial action
will address-the remaining principal threats to human health and
the environment posed by the contaminated groundwater at the
site. -
v.
SUMMARy OF SITE CHARACTERISTICS
The significant findings of the Groundwater Remedial
Investigation are summarized below.
'"
A.
Overburden Groundwater
Forty two (42) wells were installed at varying depths and fifteen
(15) locations in the overburden aquifer during the RI. In
addition, nine (9) piezometers were also installed to aid in
defining the hydrogeology of the study area. Water level
measurements were recorded from each well and each piezometer on
a monthly basis. Based on the water level data, EPA has
determined that groundwater in the overburden aquifer flows in a
north and northwest direction. Some of the groundwater
discharges into Tarkiln Brook. However, there is also a
component of flow in the deep portion of the overburden aquifer
that passes under the brook and discharges into the Slatersville .
Reservoir to the west of the brook. The magnitude of the
component of flow which passes under the brook varies seasonally.
This observation is based on a review of the groundwater
elevation contour maps prepared with the water level data from
the wells in the deep portion of the overburden aquifer and
without the surface water elevations of Tarkiln Brook. Figure 3
in Appendix A is an example of one such groundwater contour map
based on data collected during the month of February 1989.
Groundwater flows in a direction which is perpendicular to the
contours.
Groundwater samples were taken quarterly at each of the
monitoring wells and analyzed for over 100 different
contaminants. The RI found that volatile organic compounds
(VOCs) are the principal site-related groundwater contaminants.
Table 1 in Appendix B identifies the VOCs detected, the
concentrations, and the frequency of detection in the overburden
groundwater. Some semi-volatile organic compounds (SVOCs) and
metals were also detected in the groundwater. However, the
concentration and frequency of detection for both the SVOCs and
metals were low and below KCLs. Tables 2 and 3 in Appendix B
identify t~e SVOCs and metals detected, the concentrations, and
the frequency of detection in the overburden groundwater,
respectively. .
Based on the analytical results of the groundwater monitoring
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ROD DECISION SUMMARY
Western Sand' Gravel Site
Page 8
contamination in the overburden aquifer is described in Figure 4
in Appendix A~ As noted from the figure, the greatest
concentrations of contaminants are currently found at and near
the Site. Thes~ concentrations gradually decrease with distance
from the Site. In addition, the current vertical extent of
contamination in the overburden aquifer is described in Figure 5
in Appendix A. As noted from these figures, the greatest
concentrations of contaminants are found in the deeper portions
of the overburden aquifer. Concentrations of VOCs near the site
exceed federal safe drinking water standards. Concentrations of
SVOCs and metals do not.
Based on a review of the hydrological data, including the water
level data discussed above, EPA has determined that it is likely
that the historical extent of contamination could have been
larger. The potential historical maximum areal extent of
contamination is described in Figure 6 in Appendix A. The total
concentrations of VOCs presented in Figure 6 are based on data
collected in 1983 during the first RIfFS. Based on a comparison
of the current and historical data, EPA has concluded that the
magnitude and extent of contamination has decreased significantly
and will continue to decrease with time as the integrity of the
cap is maintained.
B.
Bedrock Groundwater
The bedrock system at the site consists of an uppermost zone of
bedrock which is weathered and fractured and a lower competent
(less fractured) zone which contains isolated zones of horizontal
and vertical fracturing. Groundwater in the upper weathered
fractured zone can readily move into and out of the
unconsolidated sediments above. Therefore, the uppermost zone of
the bedrock is considered part of the overburden aquifer. The
following discussion of the bedrock system pertains to the lower
competent zone of the bedrock system.
In order to determine if the bedrock system was contaminated, two
bedrock wells were installed in the lower competent zone of the
bedrock system. The 'bedrock well locations were selected based
on the sampling results from the overburden aquifer and were
located in areas which had elevated concentrations of
contaminants in the deep portion of the overburden aquifer.
Groundwater samples were taken from the two bedrock wells and
found to be contaminated primarily with VOCs. Table 4 in
Appendix B identifies the concentrations of VOCs and SVOCs
detected in groundwater from the bedrock wells. Since metals
were not detected in the overburden groundwater at significant
concentrations, samples from the bedrock were not analyzed for
metals.
Hunt has concluded that the contamination found in the bedrock
wells is from faulty well seals which resulted in contaminated
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ROD DECISION SUMMARy
Western Sand' Gravel site
.
Page 9
system due to artificially induced vertical migration. Hunt
theorizes that during the sampling process, the bedrock wells
were comp!e~ely evacuated (emptied). The evacuation created an
exaggerated head difference between the surrounding overburden
aquifer and the bedrock wells. In other words, once water was
evacuated during sampling, the water levels in the bedrock wells
were s~bstantially lower than the water levels in the overburden
aquifer. Since groundwater tends to flow from areas of higher
water elevation to areas of lower water elevation, the evacuation
created a large artificially induced downward flow potential.
Bedrock wells are typically constructed with seals to prevent the
groundwater in the overburden from interacting with the bedrock
wells. However, if the well seals are faulty, groundwater could
flow from the overburden aquifer into the bedrock wells and
contaminate the bedrock system. EPA agrees that this theory is
possible though certainly not conclusive. However, since it is
impossible to examine the integrity of these wells, this theory
cannot be verified by the data collected during the RI.
Furthermore, if the wells are faulty, conclusions regarding the
bedrock system are questionable.
EPA believes that there is another explanation for the
contamination detected in the bedrock wells. Contaminated
, groundwater could have migrated under natural conditions and
contaminated the groundwater in the bedrock system. As stated
above, the greatest concentrations of contaminants have been
detected in the deep portion of the overburden aquifer. If a
fracture is present in the bedrock system in these areas, there
is a potential for contaminants to migrate from the overburden
aquifer into the bedrock system under natural conditions. Since
a fracture network analysis was not conducted during the RI to
locate the fractures, the possibility of the presence of
fractures in these areas cannot be ruled out. The fact that
there are a number of residential wells drilled into the
competent zone of the bedrock system which provide some
residential homes with water is evidence of substantial
groundwater flow in the fracture network in this area.
Furthermore, some of the residential bedrock wells have shown
contamination throughout the history of the Site. This
contamination may be from the site or from unknown sources.
CUrrently, these residential wells are treated prior to use.
In summary, EPA has determined that there are two possible
explanations for the contamination detected in the bedrock wells.
One possible explanation is that the groundwater migrated under
natural conditions. The other possible explanation is that the
contamination resulted from faulty wells. However, even if the
wells are faulty, the possibility that the bedrock system is
contaminated remains. Therefore, further data must be collected
to verify whether or not the bedrock system is contaminated.
Presently, there are two (2) bedrock wells designated C-4B and
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.
. ROD DECISION SUMMARY
Western Sand & Gravel Site
Page 10
shall moni~or these wells on a quarterly basis for VOCs for one
year. In addition, three (3) additional bedrock wells shall be
installed pursuant to the Consent Decree. These wells shall also
be monitored on-a quarterly basis for VOCs for one year at a
minimum.
C.
Residential Wells
During the RI, information was gathered on the location and depth
of the existing residential wells. Much of the information was
obtained through discussions with the current property owners.
In many instances, the information obtained was not supported by
well installation boring logs. Based on the information
gathered, twelve (12) residential wells are known to be drilled
into the overburden aquifer, fourteen (14) residential wells are
known to be drilled into the bedrock and fourteen (14)
residential wells are of unknown depth. Maps identifying each of
these groups are presented in the Revised Groundwater RI Report.
In evaluating the impacts of the site on the residential wells,
EPA considered a number of factors. First, as stated above,
there is very limited information on the construction and depth
of the residential wells. Second, the full extent of
contamination in the bedrock system has not been determined.
Third, the sampling location for the residential wells is between.
a small storage tank and the carbon filtration units. This
location may not provide analytical results which are
representative of the groundwater in the aquifer. Fourth, there
is very little historical data available for the area to the west
of the site between the Site and Pulaski Road. In conclusion,
due to a number of factors, it is difficult, if not impossible,
to determine exactly which residential wells have been impacted
by the site. However, based on a review of the hydrologic and
analytical data collected, the following conclusions can be made:
.
D.
.
Eight ~8) of the twelve (12) residential overburden
wells are located downgradient from the Site and are
located in the path of a potential site plume during at
least a portion of the year. The other four (4)
overburden residential wells are located upgradient
from the site.
.
Due to the uncertainties regarding the extent of
contamination in the bedrock, it is not possible to
identify positively which of the residential bedrock
wells have been impacted by the site.
For the wells of unknown depth, conclusions regarding
impacts from the Site can not be made.
Surface Water and Sediments
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~
ROD DECISION SUMMARY
Western Sand' Gravel Site
Page %1
j.
area of the site and flows north discharging into the
Slatersville Reservoir. six (6) locations in Tarkiln Brook were
sampled d~ing the RI. The sampling locations included one
location that was upgradient from the Site and one location at
the mouth of the Slatersville Reservoir.
~
Several volatile organic compounds (VOCs) were detected at two
(2) downgradient surface water sampling locations along Tarkiln
Brook. The concentrations of VOCs detected at these two
locations are presented in Table 5 in Appendix B. Isophoron at 2
ppb is the only semi-volatile organic compound (SVOC) .that was
detected in the surface water downgradient from the Site. Four
(4) metals, aluminum, barium, copper and zinc were detected. in
the surface water. Copper and zinc were also detected at the
upgradient locations. The concentrations of these metals are
also presented in Table 5 in Appendix B.
Four (4) VOCs, acetone, chloroform, methylene chloride and
tetrachloroethene, were detected in the sediments of Tarkiln
Brook. The concentrations of VOCs detected in the sediments are
presented in Table 6 in Appendix B. Several SVOCs were detected
at the upgradient sampling location and at one downgradient
sampling location. The concentrations of SVOCs detected in the
sediments at these locations are also presented in Table 6 in
'Appendix B. Finally, several metals were also detected in the
sediments. Elevated levels of metals were detected at one
downgradient location as compared to the upgradient location.
The concentrations of metals detected in the sediments at these
locations are also presented in Table 6 in Appendix B.
As stated above, one sample was taken at the mouth of the
Slatersville Reservoir. No contaminants were detected in this
sample. These results can be explained by the fact that the
detectable portion of the contaminant plume currently does not
extend into the Reservoir. Therefore, the source for
contamination in the Reservoir no longer exists.
Additional information on the site characteristics can be found
in Sections 4.0 and 5.0 of the Groundwater Remedial Investigation
Report (June, 1990) and in the Groundwater Remedial Investigation
Report Addendum (November, 1990).
VI.
SUMMARY OP SITB RISKS
A Risk Assessment (RA) was performed to estimate the probability
and magnitude of potential adverse human health and environmental
effects from exposure to contaminants associated with the site.
The public health risk assessment followed a four step process:
1) contaminant identification, which identified those hazardous
substances which, given the specifics of the site were of
significant concern; 2) exposure assessment, which identified
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.
.. ROD DECISION StJHMARy
Western Sand' Gravel site
Page 12
potentially exposed populations, and determined the extent of
possible exposure; 3) toxicity assessment, which considered the
types and magnitude of adverse health effects associated with
exposure to hazardous substances, and 4) risk characterization,
which integrated the three earlier steps to summarize the
potential and actual carcinogenic and noncarcinogenic risks posed
by hazardous substances at the site. The results of the public
health risk assessment for the Western Sand and Gravel Site are
discussed below followed by the conclusions of the environmental
risk assessment.
;
Fifty contaminants of concern for groundwater, eighteen for
surface water and ten for sediment, listed in Tables 7 and 8 in
Appendix B, were selected for evaluation in the risk assessment.
A detailed summary of contaminants found within each group along
with the frequency, concentration, range and average
concentration is presented in Tables 6.2 through 6.8 of the RI
Report (June, 1990) for the Site. These contaminants constitute.
a representative group of the more than fifty contaminants in
groundwater, 21 in surface water and 36 in sediments which were
identified at the Site during the RI. Contaminants of concern
were selected to represent potential site related hazards based -
on toxicity, concentration, frequency of detection, and mObility
and persistence in the environment. A summary of the health
effects of each of the contaminants of concern is presented in
Section 6.2.4 and in Appendix AB of the RI Report (June, 1990).
Potential human health effects associated with exposure to the
contaminants of concern were estimated quantitatively through the
development of several hypothetical exposure pathways. These
pathways were developed to reflect the potential for exposure to
hazardous substances based on the present uses, potential future
uses, and location of the Site. The following is a brief summary
of the exposure pathways evaluated. A more thorough description
can be found in Section 6.4 of the RI Report (June, 1990). For
each pathway evaluated, an average and a reasonable maximum
exposure, (RME), estimate was generated corresponding to exposure
to the average and the maximum concentration detected in that
particular medium. ..
A.
Exposure Pathways
1.
Residential use of groundwater
The exposure pathways identified for the residential use of
groundwater were 1) ingestion of drinking water, 2) inhalation of
volatile compounds released indoors from household use of
contaminated groundwater and 3) dermal contact during showering
and bathing. Ingestion of drinking water was evaluated by
assuming that a 70 kg individual would ingest two liters of water
,per day for a lifetime. These assumptions were considered
representative of a possible future exposure scenario. A current
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RO~ DECISION SUMMARY
Western Sand' Gravel site
Page 1'3
~
area accessing groundwater all have treatment systems in place.
Dermal contact with household water and inhalation of indoor air
was not quantitated but instead was discus~ed qualitatively in
the Uncertainty Analysis of the risk assessment in Section 6..6 of
; the RI Report (~une, 1990).
2.
Recreational use of surface water and sediments
Study area surface water bodies include Tarkiln Brook which flows
into the Slatersville Reservoir and a seep area adjacent to the
Site. Since contamination was not detected in Slatersville
Reservoir, exposure to study area surface water bodies is defined
here as exposure to Tarkiln Brook and the adjacent seep. Three
exposure pathways were identified for a recreational use of
, Tarkiln Brook and the seep; 1) dermal contact with surface water
and sediments, 2) incidental ingestion of surface water and
sediments and 3) ingestion of fish from Tarkiln Brook.
The exposure scenarios assumed that children, ages 6 to 15, may
come in contact with surface water and sediments 21 times a year
for 2.6 hours at a time. For each wading event, a child was
assumed to incidentally ingest 50 milliliters of surface water
and to contact legs, hands and feet with surface water and -
: sediments. The exposure intakes quantitated for dermal and oral
'exposure to surface water were combined to produce a total intake
from surface water bodies. These exposure assumptions were
considered representative of current and future use of the area.
Ingestion of fish and sediments was considered to contribute
negligible amounts to total exposure and so was not
quantitatively evaluated. Table 9 in Appendix B lists all
exposure assumptions incorporated into the risk scenarios.
B.
Risk Characterization
Excess lifetime cancer risks were determined for each exposure
pathway by multiplying the exposure level with the chemical
specific can~er pctency factor. Cancer potency factors have been
developed by EPA from epidemiological or animal studies to
reflect a conservativ.e "upper bound" of the risk posed by
potentially carcinogenic compounds. That is, the true risk is
unlikely to be greater than the risk predicted. The resulting
risk estimates are expresled in scientific notation as a
probability (e.g. 1 x 10- for 1/1,000,000) and indicate (using
this example), that an individual is not likely to have greater
than a one in a million chance of developing cancer over 70 years
as a result of site-related exposure. Current EPA practice
considers carcinogenic risks to be additive when assessing
exposure to a mixture of hazardous substances.
The hazard index was also calculated for each pathway as EPA's
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. ROD DECISION SUMMARY
! Western Sand' Gravel site
Page 14
The hazard index is calculated by dividing the exposure level by
the reference dose (RfD) or other suitable benchmark for non-
carcinogenic health effects. Reference doses have been developed
by EPA to proteQt sensitive individuals over the course of a .
lifetime and they reflect a daily exposure level that is likely
to be Without an appreciable risk of an adverse health effect.
RfDs are derived from epidemiological or animal studies and
incorporate uncertainty factors to help ensure that adverse
health effects will not occur. The hazard index is often
expressed as a single value (e.g. 0.3) indicating the ratio of
the stated exposure as defined to the reference dose value (in
this example, the exposure as characterized is approx~mately one
third of an acceptable exposure level for the given compound).
The hazard index is only considered additive for compounds that
have the same or similar toxic endpoints (for example: the hazard
index for a compound known to produce liver damage should not be
added to a second whose toxic endpoint is kidney damage).
1.
Residential Use of Groundwater
Table 10 in Appendix B depicts the cumulative carcinogenic and
noncarcinogenic risk summary for the contaminants of concern in
all seven monitoring well groups for groundwater, evaluated to
reflect the potential future ingestion of groundwater
corresponding to the average and the RME scenarios. Wells were
divided into seven groups based on the type of well, (residential
or monitoring), and the location of the well relative to the
plume, (laterally and geologically).
a.
Monitoring Wells Groups 1 and 2
The wells in Group 1 were selected to represent the extent of
contamination in monitoring wells on-site in the overburden
aquifer plume while those in Group 2 were selected to represent
similar conditions but also included bedrock wells. The RME
total cancer risk predicted for these well groups are the same,
3 x 10-2. The average risk estimates are slightly different,
3 x 10-4 (Group 1) and 1 x 10-4 (Group 2). The compound that
'contributes most significantly to these carcinogenic risk
estimates is vinyl chloride which accounts for 80-97% of the
averaqe and RME risk estimates, respectively.
The RME risk estimates for the on-site monitoring wells located
within the plume exceed the Superfund target risk range of 10-4
to 10-'. The average cancer risk estimate for Group 1 slightly
exceeds the Superfund target risk range and for Group 2 is at the
upp~z enJ .of the Superfund target risk range.
A summation of all RME hazard indices for this well grouping
produces a value greater than one. When segregated by toxic
endpoint, however, the highest HI obtained is 1.5 for blood
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. -
ROD DECISION SUMMARY
Western Sand' Gravel site
Page 1~
f dichloroethene, (l,2-DCE), with a HI of 1.1. This slight
excursion of the HI was considered insignificant due to safety
factors inhe~ent in the derivation of the HI. All remaining
individual HI values- are less than one.
Maximum Contaminant Levels (MCLs), Proposed Maximum Contaminant
Levels ~PMCLs) or Secondary Proposed Maximum Contaminant Levels
(SMCLs) were exceeded for the following compounds identified in
monitoring wells from Group 1 and 2; trichloroethene (TCE), 1,2-
DCE (total), l,l,l-trichloroethane (l,l,l-TCA), tetrachloroethene
(PCE), methylene chloride, toluene, vinyl chloride,
chlorobenzene, benzene, l,l-dichloroethene (l,l-DCE), nickel,
lead, aluminum and bis(2-ethylhexyl)phthalate (DEHP).
b.
Monitoring Well Groups 3 and 4
The wells in Group 3 were selected to represent the extent of
contamination in monitoring wells off-site in the overburden
aquifer plume while those in Group 4 were to represent similar
conditions but also included bedrock wells. The average and RME
total cancer risk estimates for these well groups are the same, 7
x 10-5 and 3 x 10-3, respectively. The compound that contributes
most significantly to these risk estimates is vinyl chloride
which accounts for approximately 70 and 80% of the average and
RME risk estimates, respectively. l,l-DCE is also a significant
contributor to the risk estimates. The RME cancer risk estimates.
for both well groups is above the Superfund target risk range.
The estimated average cancer risk lor bot~ groups is within the
Superfund target risk range of 10- to 10- .
The cumulative HIs predicted for the RMEs equals 1.0. When
segregated by target endpoint, HIs fall below one, indicating
that lifetime exposure should not result in adverse non-cancer
effects.
MCLs, PMCLs or SMCLs were exceeded for the following compounds
identified in monitoring wells from Groups 3 and 4; TCE, PCE,
methylene chloride, toluene, vinyl chloride, chlorobenzene, lead,
benzene and DEHP. .
c.
Residential Well Groups 5, 6 and 7
(Group 5)
The wells in Group 5 were selected to represent all residential
wells in the overburden aquifer which were hydrogeologically
downgradient of the site and which were in the historical plume
path. The average and RME cancer risk estimates for the future
potential ingestion of water from these wells are 4 x 10- and 2
x 10-5, respectively. Nearly 90% of the predicted risk can be
attributed to three chemicals listed here in the order of their
importance; l,l-DCE, 1, 1,2, 2-tetrachloroethane, and trans-1,3-
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ROD DECISION SUMMARY
Western Sand' Gravel site
Page 16
dichloropropene (l,3-DCP). The MCL for methylene chloride was
the only standard exceeded among this group of wells. However,
its also important to note that this compound may be the result
of laboratory contamination during the sampling and analysis
process.and may not be Site related.
(Group 6)
Wells in Group 6 were selected to represent residential wells,
drilled into bedrock, which were hydrogeologically downgradient
of the site and which were in the historical plume path. The
average and RME cancer risk estimates for the !uture potential
ingestion of water from these wells is 2 x 10- and 2 x 10-5,
respectively. The majority of the predicted risk, (greater than
50 percent), is due to, l,l-DCE and l,3-DCP. only the MCL for
methylene chloride was the only standard exceeded among this
group of wells and may also be the result of laboratory
contamination.
(Group 7)
Wells in Group 7 were selected to represent residential wells of -
unknown depth potentially affected by site contamination. The
average and RME cancer risk estimates associated with the future
potential inges~ion of water from these wells are 4 x 10-7 and.
5 x 10-6, respectively. The majority of the predicted risk,
(greater than 50 percent), is due to l,l,2,2-tetrachloroethane
and l,4-dichlorobenzene. No MCLs, PMCLs or SMCLs were exceeded
in wells from this group.
Summary - Cancer Risks and Hazard Indices
The RME and average risk estimates associated with the possible
future ingestion of groundwater from the residential wells
(Groups 5,6, and 7) are all within the Superfund target risk
range. Chemical specific and total HIs for both the RME and
average exposure scenarios are well below one within each well
grouping.
2.
-Recreational use of surface water and sediments
Table 11 in Appendix B depicts the carcinogenic and
noncarcinogenic risk summary for contaminants of concern in
surface water and a seep tributary from potential present and
future exposure. Exposure parameters for both present and future
scenarios are assumed to be the same, thus there is one
calculation for surface water. 'Since exposure to this medium may
occur through qermal contact and incidental ingestion, exposure
intakes and risk estimates were combined. Calculated risks
reflect only the RME exposure scenario.
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~0~,D£CISION SUMKARY
Western Sand' Gravel site
Page 17
f
noncarc~nogenic risk summary for the contaminants of concern in
sediment from Tarkiln Brook and the seep evaluated to reflect
present apd potential future dermal contact, corresponding to the
RME. Exposure to this medium may occur though dermal contact.
Exposure parameters for the present and potential future
scenarios are assumed to be the same, thus there is one
calculation for this medium.
Summary - carcinogenic Risks and Hazard Indices
The cancer risks associated with surface water and sediments from
Tarkiln Brook and the seep are within Superfund's target risk
range. The cumulative surface water risk estimate in the seep of
4 x 10-5, is dominated by the presence of vinyl chloride. The
cumflative surface water risk estimate in Tarkiln Brook of 9 x
10- is well below the Superfund target risk range. The RME risk
estimate due to sediment exposure of 2 x 10-10 in the seep area,
is well below Superfund's target risk range. The RME HI values
for surface water and sediment are substantially lower than one.
c.
uncertainties and Conclusions of Public Health
Assessment
The potential risks for residential use of groundwater are based
solely upon the potential ingestion of untreated drinking water.
Consequently, this RA may under estimate risk because inhalation-
of volatiles released to the air during household use of
contaminated groundwater and dermal contact during showering have
not been quantitated. CUrrent research with volatile chemicals
has shown that showering, washing dishes and clothes, and
flushing of the toilet can result in elevated concentrations of
these chemicals in the indoor air. A potential also exists for
chemicals to be adsorbed through the skin during showering and
bathing. At present, models to predict exposure via inhalation
and dermal contact are still in the developmental stage and yield
highly variable results.
The exposure assessment for recreational use of the seep area and
Tarkiln Brook is conservative. The location of the highest
observed concentration is in a shallow seep tributary to the
brook. The banks of the tributary are steep and covered with
vegetation. The main portion of the brook has significantly lower
concentrations and these chemicals were not detected in
Slatersville Reservoir.
Actual or threatened releases of hazardous substances from this
Site into groundwater within the area identified in Figure 7 in
Appendix A, if not addressed by implementing the response action
selected' in this ROD, may present an imminent and substantial
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.
. ROD DECISION SUMMARY
Western Sand' Gravel site
page 18
D.
Environmental Risk Assessment
The focus of the environmental risk assessment is to identify the
potential for texic impacts to aquatic life in Tarkiln Brook and
the Sl~ersville Reservoir due to chemicals in the surface water
and sediments. The environmental risk assessment followed a
similar protocol to the public health risk assessment.
a.
Surface water
The results to the investigation of the surface water are
presented in Table 5 in Appendix B. . The results in Table 5 in
Appendix B were compared to federal aquatic water quality
criteria. In cases where federal aquatic water quality criteria
were not available, instream criteria were developed from
information published by EPA on the toxic effects to aquatic
organisms. Except for copper and zinc, all the compounds
detected in the surface water were below the federal aquatic
water quality criteria. Four locations labeled STRl, STR3, SUPL,
STR5, were sampled for metals.
Compound
STR1
STR3
SUPL
STR5
FWOC*
Copper
Zinc
69
58
44
25
30
39
43
48
1.65
15.07
Federal Water Quality criteria - Concentration instream that
should not be exceeded to minimize chronic effects based on
a hardness of 10 mg/l of CAC03. All concentrations are in
parts per billion.
As stated previously, VOCs are the primary contaminants detected
in the groundwater at the Site. Since locations STR1 and STR3
did not contain VOCs, these locations appear to be upgradient of
the discharge of contaminated groundwater from the Site.
However, STR1 contained a number of SVOCs and was determined to
be contaminated from a source other than the Site. Therefore,
STR3 appears to best represent upgradient conditions. Since
there is not clear indication of an increase in concentrations of
,contaminants downgradient from the Site, it is not clear whether
the metals detected in the surface water are from the site or
from natural conditions.
*
b.
sediments
The results to the investigation of the sediments are presented
in Table 6 in Appendix B. Since there are no federal criteria
for sediments, the results for the organic compounds in Table 6
in Appendix B were compared to federal instream aquatic water
quality criteria. In addition, the concentrations of metals in
the sediments were compared to a state wide survey of sediment
-------
..'. .. ..;,.;.;. '" ::. J~'iMARY
Western Sand' Gravel Site
Page 1~
contaminants in the sediments were below the instream criteria
for surface waters. In addition, with the exception of beryllium
and arseni9, the concentrations of metals were below the average
concentrations for other sediments in Rhode Island.
"'d.
Summary of Results
The RI Report developed by Hunt concluded that the concentrations
of contaminants in the surface water and sediments represent a
negligible potential for adverse impacts to the environment.
RIDEM has concluded that the investigations of the surface water
and sediment contamination in Tarkiln Brook and the Slatersville
Reservoir were inadequate. The state has requested, by letter
dated March 5, 1991, that Hunt conduct additional work under the
provisions of the existing Consent Decree to characterize the
impacts to Tarkiln Brook.
vxx. DEVELOPMENT AND SCREENING OF ALTERNATIVES
A.
statutory Requirements/Response Objectives
Under its legal authorities, EPA's primary responsibility at
Superfund sites is to undertake remedial actions that are
protective of human health and the environment. In addition,
Section 121 of CERCLA establishes several other statutory
requirements and preferences, including: a requirement that EPA's
remedial action, when complete, must comply with all federal and
more stringent state environmental standards, requirements,
criteria or limitations, unless a waiver is invoked; a
requirement that EPA select a remedial action that is cost
effective and that utilizes permanent solutions and alternative
treatment technologies or resource recovery technologies to the
maximum extent practicable; and a preference for remedies in
which treatment which permanently and significantly reduces the
volume, toxicity or mobility of the hazardous substances is a
principal element over remedies not involving such treatment.
Response alternatives were developed to be consistent with these
Congressional mandates.
Based on preliminary information relating to types of
contaminants, environmental media of concern, and potential
exposure pathways, remedial action objectives were developed to
aid in the development and screening of alternatives. These
remedial action objectives were developed to mitigate existing
and future potential threats to public health and the
environment. The response objectives were:
.
Restore contaminated groundwater in the overburden
aquifer, from the boundary of the existing cap to the
outer boundary of the contaminant plume, to State and
Federal applicable, relevant and appropriate
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.
. ROD DECISION SUMMARY
Western Sand' Gravel Site
page 20
.
standards, and to a level that is protective of human
health and the environment as soon as practicable.
Resto~e contaminated groundwater in the bedrock system,
to state and Federal applicable, relevant and
appropriate requirements (ARARs), including drinking
water standards, and to a level that is protective of
human health and the environment as soon as practicable
unless EPA determines, based on additional information,
that contamination in the bedrock does not exceed
protective levels.
.
Protect uncontaminated groundwater and surface water
for current and future use.
.
Prevent human and animal exposure to contaminated
groundwater.
.
Protect environmental receptors.
B.
Technology and Alternative Development and screening
CERCLA and the NCP set forth the process by which remedial
actions are evaluated and selected. In accordance with these
requirements, a range of alternatives were developed for the
site.
with respect to groundwater response actions, the RIfFS developed
a limited number of remedial alternatives that attain site
specific remediation levels within different time frames using
different technologies; and a no action alternative.
Pursuant to the Consent Decree, Hunt submitted the Revised
Groundwater FS Report to EPA and RIDEM on October 12, 1990. As
discussed in section 2 of the Feasibility Study, the RIfFS
identified~ as~essed and screened technologies based on
implementability, effectiveness, and cost. These technologies
were combined into alternatives. section 3 of the Feasibility
Study presented the remedial alternatives developed by cOmbining
the technologies identified in the previous screening process in
the categories identified in section 300.430(e) (4) of the NCP.
Each alternative developed was once again screened in Section 3
of the Feasibility Study according to effectiveness,
implementability, and cost. The purpose of the initial screening
was to narrow the number of potential remedial actions for
further detailed analysis while preserving a range of options.
In summary, Hunt developed and screened seven remedial
alternatives in section 3 of the Feasibility Study. As a result
of the screening process, five alternatives were retained by Hunt
for the detailed analysis. Table 13 in Appendix B identifies the
alternatives that were evaluated during the screening process.
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ROD DECISION SU~~\~
Western Sand' Gravel Site
.
Page 21
~
the detailed analysis.
In a letter dated January 14, 1991, EPA submitted comments to
Hunt on the Revised Groundwater FS Report. EPA's comments
focused on the detailed analysis, Section 4 of the report. To
address EPA's comments on the Revised FS Report developed by
Hunt, BPA developed the Groundwater FS Report Addendum (February
1991). The addendum contains a detailed analysis of the
alternatives developed by Hunt in the Revised Groundwater FS
Report. In addition, EPA developed and evaluated a new
alternative in the addendum. The new alternative developed by
EPA is also identified in Table 14 in Appendix B.
VIII.
DESCRIPTION OF ALTERNATIVES
This Section provides a narrative summary of each alternative
evaluated.
A.
Alternatives developed by Hunt
Hunt conducted a detailed analysis of five alternatives in the.
Revised Groundwater FS Report. A description of the alternative~
is presented below. A more detailed description of the
alternatives may be found in Section 4 of the Revised Groundwater
FS Report.
Alternative 1 (No Action)
.
.
Restoration by natural attenuation
Groundwater monitoring
Alternative 1 allows for the restoration of the contaminated
.groundwater in the overburden aquifer and bedrock system by
natural attenuation. According to hydrogeologic models presented
in the Revised Groundwater FS Report, restoration of the
groundwater to the cleanup standards presented in Table 15 in
Appendix B by natural attenuation is predicted to occur in
approximately 24 to 28 years. According to actual groundwater
data collected to date, restoration by natural attenuation may
take between 8 and 18 years. This alternative also includes a
long-term groundwater monitoring program for both the overburden
aquifer and the bedrock system. A detailed description of the
groundwater monitoring program is presented in the Groundwater FS
Report. This alternative does not include surface water or
sediment monitoring.
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
o
24 to 28 years
$ 0
$ 794,037
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.
, ROD DECISION SUMMARY
Western Sand' Gravel Site
Page 22
Alternative 2
.. .
.
.
Restoration by natural attenuation
Temporary access restrictions for.potential
reljidences
Groundwater monitoring
future
.
Like Alternative 1, Alternative 2 allows for the restoration of
the contaminated groundwater in the overburden aquifer and
bedrock system by natural attenuation. Therefore, the predicted
time frame for restoration to the cleanup standards in Table 15
in Appendix B is the same as Alternative 1. Alternative 2 .
utilizes temporary access restrictions to reduce the risk to
public health from consumption of the groundwater. The temporary
access restrictions considered by Hunt in the Groundwater FS
Report included the. following:
o
o
o
o
Deed restrictions
Zoning restrictions
Well use advisories
Restrictions on individual
permits
Acquisition of property or
sewer disposal system
o
groundwater rights
In order to evaluate temporary access restrictions, the area
needing restrictions was delineated by Hunt. Hunt utilized the 1
ppb total volatile organic compound (TVOC) plume contour as the
area needing restrictions (Appendix A, Figure 4). The area
delineated by Figure 4 is approximately 28 acres in size and
impacts 9 existing lots including the Western Sand & Gravel
Property. Hunt concluded that the most effective means to
control access was to acquire the property within the area
delineated. Therefore, Hunt conducted the detailed analysis with
acquisition of property as the institutional control. The
groundwater monitoring program for this alternative is the same
as the one utilized in Alternative 1. This alternative does not
include surface water or sediment monitoring.
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME. FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
o
24 to 28 years
$ 192,500
$ 944,981
$ 1,137,481
Alternative 3
.
.
Restoration by natural attenuation
Temporary alternate water supply for
residences
Groundwater monitoring
potential future
.
Like Alternatives 1 and 2, Alternative 3 allows for the
-------
ROD DECXSXOH SUMMARY
Western Sand' Gravel Site
Page 2!
aquifer and bedrock system by natural attenuation. Therefore,
the time for restoration is the same as Alternative 1.
Alternative 3 utilizes a .temporary alternate water supply for
future residences to reduce the risk to public health from
consumption of the groundwater. The temporary alternate water
supply considered by Hunt in the Groundwater FS Report included
the fol-Iowing:
o
o
Well head treatment
Use of existing supply system
The existing supply system considered by Hunt is the permanent
alternate water supply required by the September 1984 ROD. with
the exception of the residential connections, construction of the
system is complete. Residential connections will be completed
after RIDEM or the Nasonville Water District begins operation of
the system. The system was designed with the capacity to service
only the existing sixty (60) lots in the affected area of the
Site. Since the source for this system is located upgradient and
in the vicinity of the site, expansion beyond the 60 lot capacity
may result in contamination of the source. Therefore, this
system may not have the capacity to service any future lots
created by subdivisions. For this reason, use of the existing
system may not be feasible and was not considered any further in
the detailed analysis conducted by EPA in the Groundwater FS
Report Addendum. The groundwater monitoring program for this
alternative is t~e same as the one utilized in Alternative 1.
This alternative does not include surface water or sediment
monitoring.
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME FOR RESTORATION: .
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
o
24 to 28 years
$ 19,250
$ 1,114,162
$ 1,133,412
Alternative ~.
.
Active restoration
o Collection of contaminated groundwater by extraction
wells
Scenario 1: Collection of the 1 ppb plume
Scenario 2: Collection of the 100 ppb plume
o Groundwater treatment using an onsite treatment system
o Discharge of treated groundwater to local surface water
Temporary access restrictions or well head treatment
Groundwater monitoring
.
.
Alternative 4 restores the contaminated groundwater in the
overburden aquifer by collecting the contaminated groundwater
using extraction wells, treating the contaminated groundwater
-------
ROD DECISION SUMMARY
Western Sand & Gravel site
.
Page 24
carbon adsorption, and discharging the treated groundwater to
Tarkiln Brook. In the Revised Groundwater FS Report, Hunt
evaluated two collection scenarios for restoring the overburden
groundwater within the area delineated by the 1 ppb TVOC plume
contour~ Scenario 1 collects the entire volume of groundwater
within the area delineated by the 1 ppb TVOC plume contour
(Appendix A, Figure 4) and consists of five extraction wells.
The total discharge rate from this scenario is 132.5 gallons per
minute (gpm). Scenario 2 collects the volume of groundwater
within the area delineated by the 100 ppb TVOC plume contour and
consists of two extraction wells. The total discharge rate from
this scenario is 80 gpm. .
Some of the contaminated groundwater in the bedrock system would
be collected and treated in this alternative. The amount of
groundwater that would be collected from the bedrock system can
not be determined from the data collected to date. Groundwater
from the bedrock system that is not collected and treated would
be restored by natural attenuation.
According to the results of the hydrogeologic model, the
groundwater would be restored to the cleanup standards in
approximately 11 years for Scenario 1 and approximately 17
for Scenario 2.
years
To reduce the risks to public health from consumption of
contaminated groundwater, this alternative utilizes temporary
access restrictions as described in Alternative 2 or well head
treatment as described in Alternative 3. The groundwater
monitoring program for this alternative is the same as the one
utilized in Alternative 1; however, groundwater monitoring would
continue until the groundwater is restored which is predicted by
modeling to occur within 11 to 17 years. This alternative does
not include surface water or sediment monitoring.
With Access Restrictions
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
with Well Head Treatment
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
EST!l~TEu.TIME FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
1 year
11 to 17 years
$ 1,331,300
$ 2,789,181
$ 4,120,481
1 year
11 to 17 years
$ 1,158,050
$ 2,909,666
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ROD DECISION SUMMARY
f Western Sand' Gravel Site
,
I
Alternative 5
.
Page 25
Active restoration
o Collection of contaminated groundwater by extraction
wells-
o - Groundwater treatment using an onsite treatment system
o Discharge of treated groundwater to the aquifer with
excess flow to local surface water
Temporary access restrictions or Well head treatment
Groundwater monitoring
.
.
.
Alternative 5 is similar to Alternative 4 except this alternative
consists of one collection scenario, collection of the entire
volume of water within the area delineated by the 1 ppb TVOC
plume, and discharging the treated groundwater back into the
aquifer using groundwater injection wells. Since it is expected
that the entire flow from the treatment system may not be
assimilated using groundwater injection wells, discharge to
surface water may still be required for part of the flow.
Alternative 5 restores the groundwater to the cleanup standards
in approximately 10 years, according to modeling.
To reduce the risk to public health from consumption of
groundwater, this alternative utilizes temporary access
restrictions as described in Alternative 2 or well head treatment
as described in Alternative 3. The groundwater monitoring
program for this alternative is the same as the one utilized in
Alternative 1; however, groundwater monitoring would continue
until the groundwater is restored which is predicted by modeling
to occur within 10 years. This alternative does not include
surface water or sediment monitoring.
with Access Restrictions
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION' MAINTENANCE COST:
ESTIMATED TOTAL COST:
with Well Head Treatment
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TDKE FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
B.
Alternative 6 (Developed by BPA)
1 year
10 years
$ 1,532,540
$ 2,647,155
$ 4,179,695"
1 year
10 years
$ 1,359,290
$ 2,761,138
$ 4,120,428
After reviewing the circumstances at the site and the
alternatives developed by Hunt in the Revised Groundwater FS
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.
ROD DECISION SUMMARY
Western Sand' Gravel Site
page 26
included a pump and treat contingency should the groundwater not
be restore~by natural attenuation in the time predicted by
modeling. A more detailed description of the alternative may be
found. in Sectio~ II.B. of the Revised Groundwater FS Report
Addend~ (February 1991).
Alternative 6
.
Restoration by natural attenuation with contingent active
restoration
Temporary access restrictions for potential future
residences
Site monitoring
.
.
This alternative restores the groundwater in the overburden
aquifer and the bedrock system by natural attenuation. According
to hydrogeologic models presented in the Revised Groundwater FS
Report, Hunt determined that groundwater restoration will take
approximately 24 to 28 years. Active restoration would be
implemented to restore the contaminated groundwater if the
groundwater is not restored by natural attenuation at the rate
predicted by modeling or faster or if effective temporary access -
restrictions cannot be imposed.
EPA selected four indicator compounds to evaluate and monitor the.
effectiveness of natural attenuation. The four indicator
compounds are vinyl chloride, trichloroethene, tetrachloroethene
and benzene. For Alternative 6, the monitoring data would be .
evaluated every three years for the first nine years and every
five years thereafter to determine if natural attenuation is
restoring the contaminated groundwater at a rate at least as fast
as that predicted modeling. Active restoration would be
implemented to restore the contaminated groundwater if the
contaminated groundwater is not restored by natural attenuation
at a rate at least as fast as the rate predicted by modeling.
Depending on the results of the evaluation, active restoration
could begin at anyone of these intervals. The evaluation
process for this alternative is described in more detail in
Section II.B. of the Revised Groundwater FS Report Addendum.
The active restoration process to be utilized for this
alternative is the same as the active restoration process
utilized in Alternative 4. The collection scenario for this
alternative is the same as collection Scenario 2 in Alternative
4. Scenario 2 collects the volume of groundwater within the area
delineated by the 100 ppb TVOC plume contour. The time to
restore the groundwater using' activ~ restoration shall depend on
the concentrations of contaminants at the time when active
restoration is begun. Assuming that the area requiring
remediation at the time when active restoration is begun is equal
to the area delineated by the 100 ppb TVOC plume contour, it is
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ROD DECISION SUKMARY
Western Sand' Gravel site
.
Page 27
"
(
This alternative utilizes access restrictions to reduce the risk
to public health from consumption of the groundwater. For this
alternative, access restrictions would be imposed in the area
delineated in Figure 7 in Appendix A. This area includes the
area where the_risk to pUblic health is greater than 1 x 10-4
(i.e. in this area contaminant concentrations in groundwater
could be injurious to human health). In addition, this area also
includes a buffer zone which allows for a residential well to be
installed without drawing contaminated groundwater from the area
which poses an unacceptable risk. This buffer zone is equal to
300 feet at this Site. The risk to public health from
consumption of groundwater beyond the area delineated by EPA is 1
x 10-5 which is within EPA's acceptable risk r-ange. The area
delineated in Figure 7 is approximately 17 acres in size and
impacts four (4) existing lots including the lot owned by Western
Sand & Gravel, Inc.
The alternative iricludes a site monitoring program. The site
monitoring program includes a groundwater monitoring program
which is described in more detail in Section II.B. of the Revised
Groundwater FS Report Addendum. The groundwater monitoring
program shall operate until the groundwater is restored to
interim cleanup levels which is predicted by modeling to occur
within 24 to 28 years. In addition to requiring active
restoration if natural attenuation is not restoring the
groundwater at a.rate predicted by modeling or faster, this
alternative also requires active restoration of the groundwater
and/or long-term monitoring of the surface water and sediments if
necessary to protect Tarkiln Brook. .
Without Active Restoration
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME FOR RESTORATION:
. ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
With Active Restoration
ESTIMATED TIME FOR DESIGN & CONSTRUCTION:
ESTIMATED TIME 'FOR RESTORATION:
ESTIMATED CAPITOL COST:
ESTIMATED OPERATION & MAINTENANCE COST:
ESTIMATED TOTAL COST:
IX.
o
24 to 28 years
$ 82,000
$ 1,041,452
$ 1,123,952
1 year
11 years
$ 1,049,076
$2,990,151
$ 4,039,227
SUJOfARY 01' THE COMPARATIVE ANALYSIS 01' ALTERNATIVES
Section 121(b) (1) of CERCLA presents several factors that, at a
minimum, EPA is required to consider in its assessment of
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.
, ROD DECISION SOHMARY
Ii Western Sand' Gravel Site
Page 28
the National Contingency Plan articulates nine evaluation
criteria to be used in assessing the individual remedial
alternatives.
In the FS, a detailed analysis was performed on the alternatives
using tne nine evaluation criteria in order to select a site
remedy. The following is a summary of the comparison of each
alternative's strength and weakness with respect to the nine
evaluation criteria. These criteria and their definitions are as
follows:
Threshold Criteria
The two threshold criteria described below must be met in order
for the alternatives to be eligible for selection in accordance
with the NCP.
1.
OVerall protection of human health and the environment
addresses whether or not 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. .
2.
compliance with applicable or relevant and appropriate
requirements (ARARS) addresses whether or not a remedy will.
meet all of' the ARARs of other Federal and state
environmental laws andlor'provide grounds for invoking a
waiver.
primarv Balancina criteria
The following five criteria are utilized to compare and evaluate
the elements of one alternative to another that meet the
threshold criteria.
3.
Long-term effectiveness and permanence addresses the
criteria that are utilized to assess alternatives for the
long-term effectiveness and permanence they afford, along
with the degree of certainty that they will prove
successful.
4.
Reduction of toxicity, mobility, or volume through treatment
addresses the degree to which alternatives employ recycling
or treatment that reduces toxicity, mobility, or volume,
including how treatment is used to address the principal
threats posed by the site.
Short-term effectiveness addresses the period of time needed
to achieve'protection and any adverse impacts on human
health and the environment that may be posed during the
construction and implementation period, until cleanup goals
are achieved.
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~
ROD DECISION SUMMARY
Western Sand' Gravel Site
.
Page 29
;
6.
Implementability addresses the technical and administrative
feasibility of a remedy, including the availability of
materials and services needed to implement a particular
option.
Cost includes estimated capital and operation and
maintenance (O&M) costs, as well as present-worth costs.
7.
Modifvina criteria
The modifying criteria are used on the final evaluation of
remedial alternatives generally after EPA has received public
comment on the RIfFS and Proposed Plan.
8.
State acceptance addresses the State's position and key
concerns related to the preferred alternative and other
alternatives, and the state's comments on ARARs or the
proposed use of waivers.
community acceptance addresses the pUblic's general response
to the alternatives described in the Proposed Plan and RIfFS
report.
Following the detailed analysis of each individual alternative, a
comparative analysis, focusing on the relative performance of
each alternative against the nine criteria, was conducted.
9.
The section below presents the nine criteria and a brief
narrative summary of the alternatives and the strengths and
weaknesses according to the detailed and comparative analysis.
1.
Overall Drotection of human health and the environment
As discussed in the Summary of Site Risks above, the potential
future risks posed to human health from future exposure to
contaminated groundwater, between the capped area and Tarkiln
Brook, are outside of EPA's acceptable risk range. Since
Alternative I does not utilize adequate controls to prevent
exposure to the contaminated groundwater during restoration,
Alternative I would not protect future residents from groundwater
contamination associated with the site.
For all the other alternatives evaluated in the FS, the overall
protectiveness is dependent on the effectiveness of temporary
access restrictions or well head treatment at preventing exposure
to the contaminated groundwater during restoration. If temporary
access restrictions or well .head treatment are successfully
implemented and fully accepted DY ail affected residents, all of
the remaining alternatives would be protective of human health~
If temporary access restrictions or well head treatment are not
successfully implemented and fully accepted, protection would be
achieved when the groundwater is restored to drinking water
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.
. ROD DECISION SUMMARY
Western Sand' Gravel Site
Page 30
groundwater in approximately the same amount of time,
approximately 10 to 17 years, according to modeling.
Alternatives 2 and 3 take the longest period of time to restore
the groundwater7 approximately. 24 to 28 years, according to
modelin~.
RIDEN has concluded that the Remedial Investigation of the site
related contamination of the surface waters and sediments of
Tarkiln Brook and the Slatersville Reservoir was inadequate. In
a letter dated March 5, 1991, RIDEN requested that Hunt conduct
additional data to characterize the impacts to the surface water
and sediments. Alternatives 1 though 5 may not be protective of
the environment since they do not provide for any future
activities if the data indicates that the surface water has been
impacted. Alternative 6 is more protective than the other
alternatives ~ecause Alternative 6 allows for additional
activities such as long term monitoring and/or active restoration
of the groundwater if necessary for the protection of Tarkiln
Brook.
2.
ComDliance with ARARs
There are three types of applicable or relevant and appropriate
requirements (ARARs) referred to as chemical-specific ARARs,
location-specific ARARs and action-specific ARARs. A summary of .
the ARARs is presented in Table 16 in Appendix B.
The chemical-specific ARARs for all the alternatives are the
same. The chemical-specific ARARs are as follows:
.
Safe Drinking Water Act (SDWA) - Maximum contaminant
Levels (MCLs)
Safe Drinking Water Act (SDWA) - Maximum Contaminant
Level Goals (MCLGs)
Clean Water Act (CWA) - Ambient Water Quality Criteria
RhQd~ Island Rules and Regulations Pertaining to Public
. Drinking Water (R46-13-DWS)
Rhode Island Water Quality Regulations for Water
Pollution Control (R.I.G.L. 46-12, 42-17.1, 42-35)
Rhode Island Pollutant Discharge Elimination System
(R.I.G.L. 46-12, 42-17, 42-35)
.
.
..
.
.
All of the alternatives achieve compliance with the chemical-
specific ARARs. However, the alternatives differ in the time it
takes to achieve compliance. Alternatives 1, 2, and 3 rely on
natural attenuation to restore the groundwater to the chemical-
specific ARARs. As predicted by modeling, these alternatives
shall achieve compliance with the chemical-specific ARARs within
24 to 28 years. As predicted by actual data collected to date,
these alternatives may achieve compliance within a shorter period
of time, approximately 8 to 18 years. Alternative 4, which
utilizes active restoration with a discharge to surface water, is
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.
Page 31
ROD DECZSZON SUMMARY
~ Western Sand' Gravel site
~
,
years. Alternative 5, which utilizes active restoration with
discharges to both groundwater and surface water, is predicted to
achieve c~pliance within 10 years.
Like Alternatives 1, 2 and 3, Alternative 6 achieves compliance
through natural attenuation in approximately 24 to 28 years,
according to modeling, or faster according to actual groundwater
monitoring data. However, Alternative 6 also includes a
contingent active restoration component. specifically, if the
groundwater monitoring data indicates that the qroundwater is not
being restored by natural attenuation to ARARs within the time
predicted by modeling or faster, then Alternative 6 utilizes
active restoration to achieve compliance in approximately 11
years. This time may be decreased depending on how far natural
attenuation has progressed before active remediation occurs.
There are no location-specific ARARs for Alternatives 1, 2 and 3.
The location-specific ARARs for Alternatives 4, 5 and 6 are as
follows:
.
.
.
.
.
.
Clean Water Act, Section 404
Federal Protection of Wetlands Executive Order
Fish & Wildlife Coordination Act
Fish & Wildlife Improvement Act of 1978
, Fish & Wildlife Conservation Act of 1980
Rhode Island Freshwater Wetlands Act (R.I.G.L.
27)
2-1-18- .
The collection, treatment and discharge facilities for
Alternatives 4, 5 and 6 shall be designed and constructed in
compliance with all location-specific ARARs. Specifically, the
collection, treatment and discharge facilities would be sited so
as to minimize the destruction, loss, degradation or filling of
the wetlands. Furthermore, these facilities would be sited so as
not to jeopardize the continued existence of any endangered or
threatened species.
The action-specific ARARs for all alternatives are the
requirements of the occupational Health and Safety Act which
contain requirements for workers engaged in onsite field work.
In addition, the Department of Transportation (DOT) Rules for
Hazardous Materials contain applicable requirements for wastes
shipped offsite for laboratory analysis. These requirements
shall be complied with while conducting groundwater monitoring
activities.
In addition to the action-specific ARARs noted above, the action-
specific ARARs for Alternatives 4, 5 and 6 also include the
fOllowing laws, or requlations promulgates thereunder:
.
.
.
Clean Water Act
Clean Air Act
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.
ROD DECZSZON SUMMARY
Western Sand' Gravel site
page 32
.
.
.
~ode Island Air Pollution Control Regulations
Rhode Island Air Toxic Regulations
Rhode Island Pollutant Discharge Elimination System
Permit Regulations
-
For Alternatives 4, 5 and 6, the collection and treatment systems
shall be designed, constructed and operated in compliance with
the action-specific ARARs. Through appropriate design, emissions
from the air stripper would achieve compliance with the Clean Air
Act, the Rhode Island Air Pollution Control Act and the Rhode
Island Air Pollution Control Regulations promulgated pursuant to
that Act. These regulations, including regulations 5, 9.3.1 (e)
& (f), 9.3.3, 9.3.4, 17, 22.3.1, 22.3.3, .establish numerical
emission limits for listed substances as well as minimum
technology requirements and operating requirements. Compliance
with these regulations shall be achieved with the use of a vapor
phase carbon adsorption system to remove contaminants from the
air stripper emissions. The discharge to the local surface water
would achieve compliance with the Clean Water Act and the Rhode
Island Pollutant Discharge Elimination System Permit Regulations
via the onsite treatment system. Finally, offsite transportation
of treatment residuals would be conducted in compliance with the.
DOT Rules for Hazardous Materials.
3.
Lona-term Effectiveness and Permanence
As discussed above, the potential future risks posed to human
health from future exposure to contaminated groundwater are
outside of EPAls acceptable risk range. Since Alternative 1 does
not utilize adequate controls to prevent access to the
contaminated groundwater during restoration, Alternative 1 is not
protective over the long-term.
For the other alternatives evaluated, the long-term effectiveness
is dependent on the effectiveness of temporary access
restrictions or well head treatment at preventing exposure to the
contaminated groundwater during restoration. If temporary access
restrictions or well head treatment is effective at preventing
exposure to the contaminated groundwater during restoration, then
all the other alternatives are equally protective over the long-
term. However, if temporary access restrictions are not
effective at preventing exposure, protection is achieved when the
groundwater is restored to interim cleanup levels.
Alternatives 2 and 3, which rely on natural attenuation, take the
longest to restore the groundwater to interim cleanup levels and
ARARs, approximately 24 to 28 years according to modeling.
Alternatives 4 and 5, utilize treatment to permanently destroy
the contaminants in the groundwater reducing the concentrations
to interim cleanup levels and ARARs. Alternatives 4 and 5
restore the groundwater in approximately 10 to 17 years,
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ROD DECISION SUMMARY
Western Sand' Gravel Site
Page 33
.
.
Like Alternatives 2 and 3, Alternative 6 also relies on natural
attenuation to restore the contaminated groundwater and will take
approximat~ly 24 to 28 years to restore the groundwater.
However, if the groundwater is not restored at the rate predicted
by modeling or faster, or effective controls cannot be
implemented, Al~ernative 6 utilizes treatment to restore the
groundwater to interim cleanup levels in approximately 11 years,
according to modeling.
Reduction of Toxicitv. Mobilitv. or Volume throuah
treatment
4.
Alternatives 1, 2 and 3 do not utilize treatment to restore the
contaminated groundwater which is the principal threat at the
Site. Therefore, there is no reduction of toxicity, mobility or
volume through treatment for these alternatives.
Alternatives 4 and 5 utilize active restoration to restore the
contaminated groundwater. Alternatives 4 and 5 utilize the same
treatment processes. Alternative 4 discharges the treated
groundwater into the surface water of Tarkiln Brook or the
Slatersville Reservoir while Alternative 5 discharges a portion
of the treated groundwater into the groundwater and a portion
into the surface water. Two collection scenarios were evaluated.
for Alternative 4, collection of the 1 ppb TVOC plume (Scenario
1) and collection of the 100 ppb TVOC plume (Scenario 2).
Assuming that no hazardous substances adsorb to the soil, it is
estimated that Scenario 1 shall permanently destroy approximately
500 lbs of hazardous substances and Scenario 2 shall permanently
destroy approximately 400 lbs of hazardous substances.
Alternative 5 has one collection scenario, collection of the 1
ppb TVOC plume. Alternative 5 shall permanently destroy
approximately 500 lbs of hazardous substances.
Alternative 6 utilizes natural attenuation to restore the
contaminated groundwater. If natural attenuation restores the
groundwater.,to the interim cleanup levels effectively, there is
no reduction of ~cxicity, mObility or volume through treatment
for this alternative. However, if the groundwater is not
restored at the rate predicted by the model, Alternative 6
utilizes the s~e active restoration process as Alternatives 4
with collection Scenario 2 and therefore achieves the same
reduction. Therefore, Alternative 6 utilizes treatment to reduce
toxicity, mobility or volume to the extent necessary.
s.
Short-term Effectiveness
For all the alternatives, the potential short-term risks to the
community include the potential future risks posed from
residential use of the groundwater during restoration. Since
Alternative 1 does not utilize adequate controls to prevent
access to the groundwater during restoration, Alternative 1 is
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.
ROD DECISION SUMMARY
Western Sand' Gravel Site
Page 34
evaluated, the short-term effectiveness is also dependent on the
effectiveness of temporary access restrictions or well head
treatment at preventing exposure to the contaminated groundwater
during restoration. If temporary access restrictions or well
head treatment is effective at preventing exposure to the
contaminated groundwater during restoration, then all the other
alternatives are equally protective over the short-term.
However, if temporary access restrictions or well head treatment
are not effective at preventing exposure, protection is achieved
when the groundwater is restored to interim cleanup levels.
Alternatives 2 and 3, which rely on natural attenuation, take the
longest time to restore the groundwater to interim cleanup.
levels, approximately 24 to 28 years according to modeling.
Alternatives 4 and 5, which utilize active restoration, restores
the groundwater to interim cleanup levels in approximately 10
years, according to modeling. Like Alternatives 2 and 3,
Alternative 6 also relies on natural attenuation and restoration
of the groundwater to interim cleanup levels would also take 24
to 28 years. However, if effective controls cannot be
implemented, the preferred alternative relies on active
restoration to restore the groundwater to interim cleanup levels
in approximately 11 years according to modeling. -
Risks to workers, the community, and the environment during
construction of all the alternatives would be minimal.
Alternatives 1, 2 and 3 involve monitoring which has thus far
been successfully implemented with minimal impacts on the
community and the environment. Construction of well head
treatment systems, a component of Alternatives 3, 4, and 5, has
also been successfully implemented with minimal impacts to the
residents near this Site. Construction of the groundwater
treatment and discharge facilities for Alternatives 4, 5 and 6
would pose minimal impacts to the community since the facilities
would be located near the site. The treatment facility would be
sited within the WS&G, Inc., property boundaries which is 1000
feet from the nearest residence.
6.
ImDlementabilitv
Alternative 1 consists of groundwater monitoring utilizing
existing wells which is relatively easy to implement. The
implementability of Alternatives 2 and 3, which include either
temporary access restrictions or well head treatment,
respectively, is dependent upon the cooperation of the property
owners which cannot be determined at this time. Therefore, the
imp~3mer.tability of these alternatives is considered
questionable.
Alternatives 4 and 5 utilize active restoration consisting of
technologies that are proven, reliable and readily implementable.
However, like Alternatives 2 and 3, the implementability of
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J'
ROD. DECISION SUMMARY
Western Sand' Gravel site
Page 3!
components of both Alternatives 4 and 5, are considered
questionable. Since Alternative 5 has two discharge points, one
to groundwater and one to surface water, Alternative 5 is
technically and administratively more complicated to implement
than Alternativ~ 4. If natural attenuation is utilized, the
.. implementability of Alternative 6 is similar to Alternative 2.
However; Alternative 6 should be slightly easier to implement
than Alternative 2 since the area requiring restrictions is
smaller for Alternative 6. If active restoration is utilized,
the implementability of Alternative 6 is similar to Alternative
4.
All of the alternatives except Alternative 6 utilize the existing
bedrock wells to monitor the restoration of the bedrock system.
Due to the questionable integrity of the existing bedrock wells,
these alternatives may not be able to monitor the effectiveness
of the remedy. For Alternative 6, the long-term monitoring
program for the bedrock system shall depend on the results of the
additional investigations of the bedrock system conducted under
the provisions of the existing Consent Decree. Therefore, this
alternative is capable of effectively monitoring the performance
of the remedy.
7.
Cost
A comparison of the potential maximum total costs for each
alternative is as follows:
o with well head
treatment
Total
Total Operation & Total Costs
CaDital Maintenance (Dresent worth)
° $794,037 $794,037
$192,500 $944,981 $1,137,481
$19,250 $1,114,162 $1,133,412
$1,331,300 $2,789,181 $4,120,481
$1,158,050 $2,909,666 $4,067,716
Alternative
Alternative 1
Alternative 2
Alternative 3
Alternative 4
o with access
restrictions.
Alternative 5
o with access
restrictions
$1,532,540
$2,647,155
$4,179,695
o with well head
treatment
$1,359,290
$2,761,138
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ROD DECISION SUKMARY
Western Sand' Gravel site
Page 36
Alternative 6
o without active
restoration
$82,500
$1,041,452
$1,123,952
o with active
restotation
$1,049,076
$2,990,151
$4,039,227
8.
State AcceDtance
The state's comments on the RIfFS and Proposed Plan, as received
during the public comment period, and EPA's responses to their
comments are summarized in the Responsiveness Summary in Appendix
C of this document. The major comments received by the State are
summarized below.
The Rhode Island Department of Environmental Management (RIDEM)
does not approve of the use of natural attenuation to restore the
contaminated groundwater. RIDEM asserts that the State
Groundwater Protection Act mandates a strong policy of
restoration and non-degradation. Furthermore, the State contends
that failure to implement active restoration is in conflict with
the Act and is inconsistent with the pOlicies applied by the
Groundwater Section of RIDEM. -Therefore, the State does not
approve of the selection of Alternatives 1, 2, 3 and 6 for the
final remedy.
RIDEM has concluded that the investigations of the surface water
contamination in Tarkiln Brook and the Slatersville Reservoir
were inadequate. The State has requested, by letter dated March
5, 1991, that Hunt conduct additional work under the provisions
of the existing Consent Decree to characterize the impacts to
Tarkiln Brook. Furthermore, the State has indicated that
selection of the remedy should not be made until after the
additional data is collected.
RIDEM has also concluded that the investigations of bedrock
contamination was also inconclusive. They support EPA's position
of the need for additional investigations to further characterize
the extent of contamination in the bedrock aquifer and have
indicated that selection of the remedy should be made after the
additional data has been collected.
9.
Community AcceDtance
The comments received from the community on the RIfFS and
Proposed Plan during the public co~~ent period, and EPA's
responses to the comments are also summarized in the
Responsiveness Summary in Appendix C of this document. The
comments received by the community are summarized below.
major
One resident of the community submitted comments on the RIfFS and
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"
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ROD DECISION SUMMARY
Western Sand' Gravel Site
.
Page 37
"
restoration of the qroundwater as required by Alternatives 4 and
5. However, this resident did not support temporary access
restrictions- or well head treatment to prevent future risks to
public health. Furthermore, the Nasonville Water District (NWD)
believed that ~lternative 5 was the most protective since it
restored the groundwater in the fastest period of time and thus
should-be implemented by EPA. In addition, the NWD also
requested that additional data be collected to characterize the
impacts to the bedrock, the surface water and sediments.
Finally, if the preferred alternative is implemented, the NWD
also requested that the criteria which initiate active
restoration be made clear.
x.
THB SBLECTBD RBKBDY
This remedy is the third remedy selected for the Site. The
remedies selected in 1984 and 1985 and implemented in 1988, 1989
.. and 1990 reduced the immediate risk posed by the groundwater
contamination and reduced the source of contamination. This
remedy addresses the potential future risks caused by the
groundwater contamination remaining at the Site.
A.
Interim Cleanup Levels
Interim cleanup levels have been established for contaminants of
concern identified in the baseline risk assessment found to pose'
an unacceptable risk to either public health or the environment.
Interim cleanup levels have been set based on the appropriate
ARARs (e.g. Drinking Water MCLGs and MCLs) if available. In the
absence of a chemical siecific ARAR, or other suitable criteria
to be considered, a 10- excess cancer risk level for
carcinogenic effects or a concentration corresponding to a hazard
index of one for compounds with non-carcinogenic effects was used
.to set interim cleanup levels. In instances in which the values
'described above were not feasible to quantify, the practical
quantification limit was used as the interim cleanup level. At
the time that the interim cleanup levels described in Table 15 of
Appendix B, which are based on ARARs, have been achieved, a risk
.assessment shall be performed on the residual groundwater
contamination. This risk assessment of the residual qroundwater
contamination shall follow EPA procedures and will assess the
cumulative risks for carcinogens and non-carcinogens posed by
consumption of Site groundwater. If the risks are not within
EPA's risk management goal for carcinogens and non-carcinogens,
then the remedial action will continue until protective levels
are attained, or the remedy is otherwise deemed protective.
Because.'the aquifer at and beyond the compliance boundary of the
Site 'is"'classified according to Federal Classification Standards
as a Class IIA aquifer, a current source of drinking water, MCLs
and non-zero MCLGs established under the Safe Drinking Water Act
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. ROD DECISION SUMMARY
Western Sand' Gravel site
Page 38
Interim c1~anup levels for known and probable carcinogenic
compounds (Class A & B) have been set at the appropriate MCL or
non-zero HCLG. -Interim cleanup levels for the Class C, D and E
compounds (possible carcinogens not classified and no evidence of
carcinogenicity) have been set at the HCLG. In the absence of an
MCLG, an MCL or a proposed drinking water standard or other
suitable criteria to be considered (i.e. health advisory, state
standard), an interim fleanup level was derived for carcinogenic
effects based on a 10- excess cancer risk level considering the
ingestion of ground water.
Interim cleanup levels for compounds in groundwater exhibiting
non-carcinogenic effects have been set at the MCLG. In the
absence of a MCLG, interim cleanup levels for non-carcinogenic
effects have been set at a level thought to be without
appreciable risk of an adverse effect when exposure occurs over a
lifetime (hazard index = 1).
Table 15 in Appendix B summarizes the interim cleanup levels for
carcinogenic and noncarcinogenic contaminants of concern
identified in groundwater. Five compounds identified as
contaminants of concern do not have interim cleanup levels. The
five compounds are arsenic, beryllium, cadmium, chromium, and
copper. These compounds do not have interim cleanup levels
because they are currently below the specific MCLG, MCL, proposed
drinking water standard or other suitable criteria to be
considered.
-
The point of compliance for groundwater at the Site is the
perimeter of the cap represented by closure well clusters C-1
through C-6. EPA has estimated that these interim cleanup levels
will be obtained within 24 to 28 years as predicted by
hydrogeologic models. According to a review of the actual
groundwater monitoring data collected to date, EPA has estimated
that the interim cleanup levels may be achieved in a faster
period of time, approximately 8 to 18 years.
While these cleanup levels are consistent with ARARs, a
cumulative risk that could be posed by these compounds may exceed
EPA's goals for remedial action. Consequently, these levels are
considered to be interim cleanup levels for groundwater.
Furthermore, once all the ARARs have been achieved in
groundwater, EPA expects that due to different rates of
attenuation for each compound, levels of most contaminants will
be below these interim cleanup levels. Thus, when all of the
ARARs have been attained, a risk assessment will be performed on
the residual groundwater contamination to determine whether the
remedial action is protective. Remedial actions shall continue
until protective concentrations of residual contamination have
been achieved or until the remedy is otherwise deemed protective.
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.
ROD DECZSZON SUMMARY
Western Sand' Gravel Site
Page ~9
~
cleanup. levels for this Record of Decision and shall be
considered performance standards for any remedial action.
B.
Description of Remedial Components
The selected remedy has the following three major components.
A detailed description of each of the components is provided
below.
1.
Restoration of contaminated qroundwater by natural
attenuation with continqent active restoration
The selected remedy restores the groundwater in the overburden
aquifer and the bedrock system by natural attenuation. According
to hydrogeologic models presented in the. Revised Groundwater FS
Report, .Hunt determined that groundwater restoration will take
approximately 24 to 28 years. Active restoration shall be
implemented to restore the contaminated groundwater if the
groundwater is not restored by natural attenuation at the rate
predicted by modeling or faster.
In addition to requiring active restoration if natural
attenuation is not restoring the groundwater at a rate predicted.
by modeling or faster, there are three other scenarios which
trigger active restoration. First, the selected remedy also
requires active restoration of the groundwater and/or long-term
-monitoring of the surface water and sediments if necessary to
protect Tarkiln Brook. Second, based on a review of the new
information collected to characterize. bedrock impacts, active
restoration and/or long-term monitoring may be implemented if
necessary for the protection of public health and the
environment. Finally, if effective institutional controls cannot
be implemented, the selected remedy utilizes active restoration
to restore the groundwater. Such controls may include regulatory
restrictions, acquisition of affected properties or groundwater
rights, and other restrictions on property transactions.
Periodic Evaluation of Natural Attenuation
Groundwater monitoring data shall be evaluated every three years
for the first nine years, and every five years thereafter to
determine if natural attenuation is restoring the contaminated
qroundwater at the rate predicted by modeling or faster. The
evaluation consists of comparing the actual data collected during
future groundwater monitoring to the theoretical data predicted
by hydrogeologic models. The evaluation shall be conducted on
four indicator compounds: vinyl chloride, trichloroethene,
tetrachloroethene and benzena. The8e compounds were selected
based on toxicity, persistence in the environment and the
magnitude and frequency of detection.
EPA qenerated equations for each of the indicator compounds which
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~.
.
" ROD DECISION SUMMARY
Western Sand' Gravel Site
Page 40
at any point in the future. These equations were developed from
the results of" three hydrogeologic models, MODFLOW, STLINE and
the EPA Batch Flushing Model. The evaluation shall consist of
comparing the aetual concentrations to the theoretical
concent~ations as determined by the following equations:
Benzene: y = antilog (1.359 - 0.015(x»
Tetrachloroethene: y = antilog (1.804 - 0.004(x»
Trichloroethene: y = antilog (1.955 - 0.014(x»
Vinyl Chloride: y = antilog (2.117 - 0.020(x»
where
x = number of months after the ROD signing (i.e.
x = 1 for April 1991, x = 2 for May 1991,
etc.)
y = theoretical concentrations of contaminant
(ppb)
A statistical comparison of the actual data to the theoretical
data shall be conducted using the nonparametric distribution free
signed rank test of Wilcoxon with a 95 percent significance level.
as described in " Nonoarametric statistical Methods (by Hollander
and Wolfe, published by John Wiley in 1973, on pages 26-38). In
summary, the rank test determines whether the trend established
by actual data falls below the trend established by the
theoretical data. If the trend for the actual data does not fall
below the trend for the theoretical data as determined by the
rank test, active restoration shall be implemented. All
compounds must pass the rank test. If one compound fails the
rank test then active restoration shall be implemented.
The statistical comparison shall be done with the data from the
following well clusters: C-2, C-3, C-4, C-5, C-6, I-2, I-3, I-6
and I1-3. These nine clusters are the most contaminated well
clusters at the Site. The sum of the maximum concentration in
each of these 'well clusters, for each indicator compound, shall
be the basis for the comparison. Due to the proximity of well
clusters C-5 and 11-3, the cluster with the greatest
concentration during the particular sampling episode shall be
selected for the comparison.
An example of the evaluation using the rank test is presented in
Appendix D of the ROD using the data collected during the RI for
Benzene. EPA believes that this approach eliminates any
vagueness in the trigger for active remediation as it relates to
qroundwater contamination.
Since wastes remain at the Site, EPA will review the Site, to the
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~O~ DECISION SUKMARY
Wes~ern Sand' Gravel Si~e
Page 11
remedial action continues to protect human health and the
environment. During these periodic reviews, EPA shall also
consider an~ recently promulgated standards that would have been
ARARs had they been promulgated at the ~ime of remedy selection
to insure that_the remedy remains fully protective in light of
such new standards. EPA may also consider any newly promulgated
standards sooner than these evaluation periods if appropriate.
Active Restoration Process
The active restoration process to be utilized for this
alternative shall consist of collecting the contaminated
groundwater using extraction wells, treating the contaminated
groundwater using sedimentation, filtration, an air stripping
column and carbon adsorption, and discharging the treated
groundwater to Tarkiln Brook. The collection system shall be
designed to collect the volume of groundwater within the area
delineated by the '100 ppb TVOC plume contour (Appendix A, Figure.
4). The exact location of the extraction wells and the optimum
pumping rate shall be determined by pump tests conducted during
predesign studies.
The extracted groundwater shall be collected in a sedimentation -
tank where suspended solids and metals shall be removed (Appendix
A, Figure 8). The groundwater shall then be pumped into a filter
for further removal of metals and suspended solids. The solids
from the sedimentation and filtration system shall be disposed of
in a facility licensed to accept such wastes. Land disposal of
these solids may be impacted by the RCRA land disposal
requirements. Tests shall be performed during operation to
determine if these solids are Characteristic RCRA Hazardous
Wastes and restricted under the land disposal requirements.
From the filter, the groundwater shall be pumped into a counter
current air stripper for removal of VOCs. The air emissions from
the air stripper shall be passed through a vapor phase carbon
adsorber for removal of the VOCs from the air prior to discharge
to the atmosphere. The treated groundwater effluent from the air
stripper shall also be passed through a liquid phase adsorber for
. removal of VOCs. The treatment system shall be designed to meet
the numerical effluent limits based on state water quality
standards. The effluent shall be tested periodically to
.demonstrate that the effluent continues to meet effluent limits.
2.
Ins~i~u~ional con~rols for po~en~ial fu~ure
residences
The selected remedy utilizes institutional controls to reduce the
risk to public health from consumption of the groundwater. For
this alternative, institutional controls shall be imposed in the
area delineated in Figure 7 in Appendix A. This area includes
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.
, ROD DECISION SUMMARY
- Western Sand' Gravel Site
Page 42
4 (i.e. in this area contaminant concentrations in groundwater
could be injurious to human health). In addition, this area also
includes a buffer zone which allows for a residential well to be
installed without. drawing contaminated groundwater from the area
which poses an unacceptable risk. This buffer zone is equal to
300 fee~ at this Site. The risk to public health from
consumption of groundwater beyond the area delineated by EPA is 1
X 10-5 which is within EPA's acceptable risk range. The area
delineated in Figure 7 is approximately 17 acres in size and
impacts four existing lots including the lot owned by Western
Sand & Gravel, Inc.
3.
site monitoring
The third component of the selected remedy is a site monitoring
program. The site monitoring program shall include, at a
minimum, long-term monitoring of the overburden groundwater. In
addition, the site monitoring program may include long-term
monitoring of the bedrock system, the surface water, and the
sediments.
Overburden Aauifer Groundwater Monitorinq Plan
The groundwater monitoring program shall operate until the
groundwater is restored which is predicted by modeling to occur
within 24 to 28 years.
The groundwater monitoring program for the overburden aquifer is
as follows:
.
The following twenty eight (28) wells shall be monitored on
a quarterly basis for volatile organic compounds (VOCs) and
on an annual basis for semi-volatile compounds (SVOCs) and
metals.
C-1 C-3S C-SS I-2S I-6S
C-2S 'C-3M C-SM I-2M I-6M
C-2M C-3D C-SD I-2D I-6D
C-2D C-4S C-6S I-3S II-3S
C-4M C-6M I-3M II-3M
C-4D C-6D I-3D II-3D
A review of the analytical data presented in the RI Report
indicates that, with the exception of C-1 which is
upgradient of the Site, these wells were the most
contaminated wells in the plume (See Figure 4.2 in RI
Report, Hunt, June 1990). All of these wells shall be
utilized to evaluate the effectiveness of natural
attenuation. Quarterly monitoring is needed to provide
enough data to evaluate statistically the effectiveness of
natural attenuation. In addition, it is anticipated that
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ROD.DEC~B~~~ SUMMARY
Western Sand' Gravel site
.
Page 43
greatest in the first six (6) years. Therefore, quarterly
monitoring must be conducted for a minimum of six (6) years.
-
VOCs are the most prevalent compounds detected at the 5ite.
Furthermor~, VOCs result in the greatest risk to public
health. Therefore, the monitoring program includes long-
term monitoring of VOCs to insure that the plume continues
to decrease in magnitude and extent. In addition, some
5VOCs and metals have also been detected in the groundwater.
Based on EPA's review of the data, these compounds are not
expected to increase in magnitude and extent. However, due
to concerns raised by RIDEM on the impacts to Tarkiln Brook
and in order to verify this conclusion, annual monitoring of
5VOCs and metals has also been included in the monitoring
plan.
RIDEM also has concerns regarding the presence of non-
aqueous phase liquids (NAPLs). Therefore, in response to
RIDEM's concern, the selected remedy includes the use of an.
interface probe to identify the presence of NAPLs.
Four VOCs have "been selected as indicator compounds to
evaluate the effectiveness of natural attenuation. All of
the monitoring results shall be reviewed by EPA. EPA
suspects that all the compounds detected at the 5ite shall
behave in a similar fashion to the indicator compounds
selected. If EPA determines that the results do not support
EPA's conclusions, EPA shall modify the selected remedy to
insure that the remedy remains protective. After a minimum
of three years of monitoring, the monitoring plan may be
modified to reduce the frequency of sampling if approved by
EPA.
. In addition, the following twenty eight (28) wells shall be
monitored on an semi-annual basis for VOCs.
1-:15 . I-55 1-85 11-45 11-65
. I-1M. I-5M I-8M II-4M II-6M
I-ID I-5D I-8D II-4D II-6D
1-45 1-75 11-25 II-55
I-4M I-7M II-2M II-5M
I-4D I-7D II-2D II-5D
These wells were found to be in the overburden plume or just.
outside of the plume during the RI. As stated above, EPA
has concluded that the magnitude and extent of contamination
in the overburden aquifer is decreasing. In addition, EPA
has concluded that there is a small component of flow which
passes under Tarkiln Brook and discharges into the
5latersville Reservoir. This conclusion is based on seven
sampling episodes over a two and a half year period.
However, due to concerns raised by RIDEM on the potential
-------
.
. ROD DECISION SUMMARY
Western Sand' Gravel site
Page 44
with a9ditional long-term data. After a minimum of three
years 'of-monitoring, the monitoring plan may be modified to
reduce the frequency of sampling if approved by EPA.
Bedrock~vstem Groundwater Monitorinq Plan
Presently, there are two bedrock wells designated C-4B and 11-
3B. Under the provisions of the existing Consent Decree, Hunt
shall monitor these wells on a quarterly basis for volatile
organic compounds for one year. In addition, three additional
bedrock welis shall be installed pursuant to the Consent Decree.
These wells shall also be monitored on a quart~rly basis for
volatile organic compounds for one year. . After evaluating the
results of the bedrock investigation, EPA will determine if it is
necessary to modify this alternative to include active
restoration and/or long-term monitoring of the bedrock system.
Surface-water and Sediments Monitorinq Program
RIDEM has concluded that the investigation of the Site related
contamination of Tarkiln Brook and the Slatersville Reservoir was
inadequate. In addition, RIDEM has noted certain violations of
State water quality standards. RIDEM plans to request that
additional data be collected under the provisions of the existing
. Consent Decree. After reviewing this data, EPA will determine if .
it is necessary to modify the selected remedy to include active
restoration of the groundwater and/or long-term monitoring of the
surface water and sediments.
XI.
STATUTORY DETERMINATIONS
The remedial action selected for implementation at the Western
Sand & Gravel Site is consistent with CERCLA and, to the extent
practicable, the NCP. The selected remedy is protective of human
health and the environment, attains ARARs and is cost effective.
If natural attenuation restores the groundwater at a rate
predicted by modeling or faster, the selected remedy will not
satisfy the statutory preference for treatment. However, if this
does not occur ,:. the selected remedy will satisfy the statutory
preference for treatment which permanently and significantly
reduces the mobility, toxicity or volume of hazardous substances
as a principal element. Additionally, the selected remedy
utilizes alternate treatment technologies or resource recovery
technologies to the maximum extent practicable.
. A..
The Selected Remedy is protective of Human Health and
the Environment
The remedy at this Site will permanently reduce the risks posed
to human health and the environment by eliminating, reducing or
controlling exposures to human and environmental receptors
-------
ROD DECISION SUMMARY
Western Sand' Gravel site
Page 4~
r
'.
the groundwater. If the groundwater is not restored at the rate
predicted by modeling or faster, the risks posed to human health
and the environment shall be minimized through treatment.
The selected remedy reduces the potential future risks to public
health from exposure to the contaminated groundwater by restoring
the contaminated groundwater to drinking water standards. The
selected remedy utilizes natural attenuation to restore the
contaminated groundwater. According to hydrogeologic models, it
is estimated that groundwater restoration shall take
approximately 24 to 28 years. According to a review of actual
data collected to date, the predicted groundwater restoration
through natural attenuation may take 8 to 18 years. If the,
groundwater is not restored at a rate at least as fast as that
predicted by modeling, the active restoration shall be
implemented to restore the groundwater in a faster rate. It is
estimated from modeling that the groundwater shall be restored by
active restoration in approximately 11 years. However, the
actual time for restoration by active restoration shall depend on
the reductions that have occurred by natural attenuation.
The selected remedy at the completion of the remedial action will
result in human exposure levels that are within the 10-4 to 10-6 .
incremental cancer risk range and that are within the hazard
index of one for non-carcinogens. More specifically, during
groundwater restoration, the selected remedy utilizes
institutional controls to prevent use of the contaminated
groundwater and prevents human exposure to the contaminated
groundwater. In addition, the selected remedy includes site
monitoring to insure that the groundwater is restored to drinking
water standards. If the groundwater is not restored at the rate
predicted by models utilizing natural attenuation or faster, the
selected remedy utilizes active restoration to restore the
groundwater in a faster period of time.
In addition to requiring active restoration if natural
attenuation is not restoring the groundwater at a rate predicted
by modeling or faster, there are three other scenarios which
trigger active restoration. First, the selected remedy also
,requires active restoration of the groundwater and/or long-term
monitoring of the surface water and sediments if necessary to
protect Tarkiln Brook. Second, based on a review of the new
information collected to characterize bedrock impacts, active
restoration and/or long-term monitoring may be implemented if
necessary for the protection of public health and the
environment. Finally, if effective institutional controls cannot
be implemented, the selected remedy utilizes active restoration
to restore the groundwater.
Implementation of the selected remedy will not pose any
unacceptable short-term risks or cross-media impacts.
-------
.
ROD DECISION SUMMARY
Western Sand' Gravel Site
page 46
monitoring. poses minimal impacts to the community and the
environment. - Furthermore, if active restoration is utilized, the
treatment system shall be located onsite. Construction of the
system shall have minimal impacts to the community and to the
environment. The treatment system shall be designed and operated
to meet the effluent limits necessary to protect the environment.
RIDEM has concluded that the investigation of surface water
contamination of Tarkiln Brook and the Slatersville Reservoir was
inadequate. RIDEM has requested that Hunt conduct additional
sampling to characterize the impacts to the surface water. In
addition to requiring active restoration if natural attenuation
is not restoring the groundwater at a rate predicted by modeling
or faster, the selected remedy allows for additional activities
such as long term monitoring and/or active restoration of the
groundwater if nec~ssary for the protection of Tarkiln Brook. If
additional data indicates that there is an unacceptable risk to
public health or the environment, then EPA shall modify its
remedy as necessary to insure that the remedy is protective.
B.
The Selected Remedy Attains ARARs
This remedy will attain all applicable or relevant and
appropriate federal and state requirements that apply to the
site. Environmental laws from which ARARs for the selected
remedial action are derived, and the specific ARARs include:
Chemical-SDecific
.
Safe Drinking Water Act (SDWA) - Maximum contaminant Levels
(MCLs)
Safe Drinking Water Act (SDWA) - Maximum contaminant Level
Goals (MCLGs)
Clean Water Act (CWA) - Ambient Water Quality criteria
Rhode Island Rules and Regulations Pertaining to Public
Drinking Water (R46-13-DWS) .
Rhode Island Water Quality Regulations for Water Pollution
Control (R.I.G.L. 46-12, 42-17.1, 42-35)
Rhode Island Pollutant Discharge Elimination System
(R.I.G.L. 46-12, 42-17, 42-35)
.
.
.
.
.
Location-Specific
.
.
.
.
Clean Water Act, Section 404
Federal Protection of Wetlands Executive Order
Fish & Wildlife Coordination hCt
Fish & Wildlife Improvement Act of 1978
Fish & wildlife Conservation Act of 1980
Rhode Island Freshwater Wetlands Act (R.I.G.L.
2-1-18-27)
.
.
Action-SDecific
.
-------
, .
ROD DECISION 8ul'.:..,,:t::B::'. '-
Western Sand' Gravel Site
paqe #1
'.
.
.
.
.
.
.
.
Air Pollutants (NESHAPs)
OSHA Record Keepinq, Reporting and Related Regulations
OSHA ~ealth and Safety Standards
DOT Rules for Transportation of Hazardous Materials
Rhode Island Air Pollution Control Act
Rhode Island Air Pollution Control Regulations
RbQde Island Air Toxic Regulations
Rhode Island Pollutant Discharge Elimination System Permit
Regulations
To Be Considered
.
.
.
.
.
Rhode Island Groundwater Protection Act
Rhode Island Draft Groundwater Classification Regulations
EPA Risk Reference Dose
EPA Carcinogen Assessment Group Potency Factors
Threshold Limit Values
A more inclusive listing of ARARs can be found in Tables 16 in
Appendix B of this Record of Decision. . This table gives a brief
synopsis of the ARARs and an explanation of the actions necessary
to meet the ARARs. The table also indicates whether the ARARs
are applicable or relevant and appropriate to actions at the
site. In addition to ARARs, the table describes standards that
:are To-Be-Considered (TBC) with respect to remedial actions.
Location and action specific ARARs are identified in this ROD on
a general level. During remedial design a more detailed ARARs
analysis considering the specifics of design will be performed to
insure the remedy's compliance with ARARs.
C.
The Selected Remedial Action is Cost-Effective
In the Agency's judgment, the selected remedy is cost effective,
i.e., the remedy affords overall effectiveness proportional to
its costs. In selecting this remedy, once EPA identified
alternatives that are protective of human health and the
environment and that attain, or, as appropriate, waive ARARs, EPA
evaluated the overall effectiveness of each alternative by
assessing the relevant three criteria--long term effectiveness
and permanence; reduction in toxicity, mobility, and volume
through treatment; and short term effectiveness, in combination.
The relationship of the overall effectiveness of this remedial
alternative was determined to be proportional to its costs. The
-------
.
'~ ROD DEC:IS:ION SUMMARY
Western Sand & Gravel Site
Page 48
operation & Total Costs
Component -. Capital Maintenance (present worth)
site
Monitoring 0 $976,762 $976,762
-
TempOrary Access $82,500 $64,690 $147,190
Restrictions
Active $966,576 $1,948,699 $2,915,275
Restoration
------------------------------------~---------------------------
Total Costs
without Active
Restoration
$82,500
$1,041,452
$1,123,952
----------------------------------------------------------------
Total Costs
with Active
Restoration
$1,049,076
$2,990,151
$4,039,227
----------------------------------------------------------------
The selected remedy is cost effective and provides a degree of
protectiveness proportionate to its costs. The selected remedy
relies on natural attenuation to restore the groundwater to
cleanup standards. According to groundwater models, groundwater
restoration by natural attenuation is estimated to take
approximately 24 to 28 years. According to an analysis of the
actual data collected to date, groundwater restoration by natural
attenuation may occur in approximately 8 to 18 years. According
to hydrologic models, active restoration of the groundwater is
estimated to take approximately 11 to 17 years. Active
restoration is approximately $3,000,000 more expensive than
natural attenuation and may not provide a significant reduction
in the amount of time necessary to restore the groundwater.
Therefore, natural attenuation is less costly than active
restoration and may be as effective as active restoration. If
the groundwater is not restored at the rate as predicted by
models or faster, or if institutional controls cannot be imposed
to insure that the remedy is protective, then the selected remedy
utilizes active restoration to restore the groundwater in a
faster period of time.
D.
~he Selected Remedy Utilizes Permanent Solutions and
Alternative ~reatment or Resource Recovery Technologies
to the Maximum Extent Practicable
Once the Agency identified those alternatives that attain or, as
appropriate, waive ARARs and that are protective of human health
and the environment, EPA identified which alternative utilizes
permanent solutions and alternative treatment technologies or
resource recovery technologies to the maximum extent practicable.
This determination was made by deciding which one of the
-------
ROD DECISION SUMMARY
Western Sand, Gravel Site
Page -M
i.
identified alternatives provides the best balance of trade-offs
among alternatives in terms of: 1) long-term effectiveness and
permanenc~; 2) reduction of toxicity, mobility or volume through
treatmentf 3) short-term effectiveness; 4)implementability; and
5) cost. The balancing test emDhasized long-term effectiveness
and permanence and the reduction of toxicity, mobility and volume
throug~ treatment; and considered the preference for treatment as
a principal element, the bias against off-site land disposal of
untreated waste, and community and state acceptance. The
selected remedy provides the best balance of trade-offs among the
alternatives.
with the exception of Alternative 1, the long-term effectiveness
of all the alternatives depended on the effectiveness of
institutional controls. If effective institutional controls were
implemented and fully accepted, all the alternatives were equally
protective over the long-term. If effective institutional
controls are not implemented, those alternatives that restored
the groundwater in the fastest period of time were considered
more effective over the long-term. If effective institutional
controls cannot be implemented, the selected remedy utilizes
active restoration to restore the groundwater in the fastest time
feasible and is therefore more effective over the long-term.
, The selected remedy utilizes natural attenuation to restore the
groundwater which is significantly easier to implement and is
less expensive than active restoration while restoring the
groundwater in a time frame that is reasonable given the
circumstances of the site. Such circumstances include the
following: the present availability of an alternate water supply
to affected residences; the groundwater plume has reached its
maximum extent and is decreasing in magnitude and extent; and,
natural attenuation has been demonstrated with long-term site
specific data to effectively reduce the contamination at the
site. In addition, the selected remedy allows for additional
activities such as long-term monitoring and or active restoration
of the groundwater if additional data indicates that such
activities are necessary for the protection of the environment.
Both the state and the community requested that active'
restoration be implemented immediately to restore the
contaminated 'groundwater. EPA considered the concerns of both
the state and the, community and determined that, considering the
limited areal extent of contamination and location of the
groundwater plume, active restoration may not provide any
advantages over natural attenuation and is not immediately
practicable within the limits of CERCLA and the NCP.
The selected remedy utilizes 'natural attenuation to restore the
contaminated groundwater. If natural attenuation restores the
groundwater to the interim cleanup levels effectively, there is
no reduction of toxicity, mObility or volume through treatment
-------
.
, ROD DECISION SUKMARY
" Western Sand & Gravel Site
Page SO
restored at the rate predicted by modeling or faster, the
selected remedy utilizes active restoration to achieve the
necessary reductions of toxicity, mobility and volume.
Therefore, the ~elected remedy utilizes treatment to reduce
toxicity, mobility or volume to the extent necessary. At this
Site, treatment shall be used to the maximum extent practicable.
However, due to the circumstances of the Site, treatment will
only be practicable if the natural attenuation remedy does not
restore the groundwater at the rate predicted by modeling or
faster. Furthermore, the remedy achieves the best balance among
the other criteria.
E.
The Selected Remedy does not satisfy the Preference for
Treatment which Permanently and significantly reduces
the Toxicity, Mobility or Volume of the Hazardous
Substances as a principal Element
The selected remedy relies on natural attenuation to restore the
contaminated groundwater which is the principal threat.
Treatment was not utilized to restore the contaminated
groundwater because it was determined not to be practicable
considering the circumstances at the site. Based on a review of
the hydrologic models, it is estimated that the groundwater may
be restored to interim cleanup levels in approximately 24 to 28
years which is a reasonable period of time given the
circumstances of the Site. Furthermore, a review of actual
groundwater monitoring data collected to date indicates that the
groundwater may be restored in a faster period of time,
approximately 8 to 18 years. According to hydrologic models,
active restoration is estimated to restore the groundwater in
approximately 11 to 17 years. Therefore, EPA concluded that
active restoration may not be any more effective than natural
attenuation in reaching the groundwater cleanup goals.
XII., DOCUMENTATION OP SIGNIPICANT CHANGES
Based on further evaluation of the selected remedy, and in
, response to comments received on the RIfFS and Proposed Plan,
EPA has modified its selected remedy in two ways. EPA believes
these changes are significant in that they impact the overall
scope, performance or cost of the remedy. However, these changes
are of such a nature that they could have been reasonably
anticipated, considering the inherent uncertainties associated
with waste management technologies.
The change regarding institutional controls allows for greater
flexibility for successful implementation of such restrictions
than was presented in the Proposed Plan. In the Proposed Plan,
EPA stated that the only contemplated institutional controls, or
access restriction, would be property purchase. The other
possible institutional controls that EPA now contemplates were
-------
ROD DECISION SUMHARY
Western Sand' Gravel Site
Page ~
to review and comment on these options.
The change regarding EPA's modified approach to evaluating the
effectiveness of natural attenuation at the site is an outgrowth
of the evaluation presented in the Proposed Plan. It is more
. comprehensive in its analysis and ensures greater reliability in
determining the success of natural attenuation.
EPA further believes that while these changes are significant,
they do not radically alter the remedy from the form in which it
was presented in the Proposed Plan. Accordingly, while these
changes are described in detail in this section, it is not
necessary to receive additional public comments on these
modifications. .'
A.
Znstitutional Controls
EPA presented a proposed plan (preferred alternative) for
remediation of the Site on February 11, 1991. The management of
migration portion of the preferred alternative included:
1.
Restoration of contaminated groundwater by natural
attenuation with contingent active restoration;
Institutional controls for potential future residences;-
and,
site monitoring.
2.
3.
The institutional controls described in the Proposed Plan
consisted of the purchase of the properties that lie within the
area requiring institutional controls, presented in Figure 7 in
Appendix A of the ROD. During the public comment period, one
local resident expressed concern that this approach may be
unnecessary while enriching those landowners closest to the Site.
Hunt also commented that property purchase may be unnecessary.
EPA has reviewed this approach in comparison to other strategies
for achieving successful institutional controls. Based on that
review EPA believes that there are several options for successful
implementation of institutional controls at the Site. Such
institutional controls may include regulatory restrictions,
acquisition of affected properties or groundwater rights, and
other restrictions on property transactions. These options are
potentially more cost effective than purchase of the affected
properties, while still attaining protection of human health
during the remediation period. Thus, EPA believes that all these
options, and ,any others that are feasible and at least equally
protective, should be explored in determining how to most
efficiently implement that portion of the ROD requiring
institutional controls.
B.
Modified Approach to Evaluation of Natural Attenuation
-------
.
ROD DECISION SUMHARY
Western Sand & Gravel site
Page 52
effectiveness of natural attenuation would be conducted. The
evaluation~r~am identified in the Proposed Plan consisted of
conducting a linear regression of the actual data and comparing
the results to ~ linear regression of the theoretical data. In
response to the comments from the Nasonville Water District and
RIDEM, EPA has clarified the language and the criteria in the
selected remedy which shall be utilized to trigger active
restoration should natural attenuation not restore the
groundwater at the rate predicted by modeling or faster. Like
the approach outline in the preferred alternative, the evaluation
consists of comparing the actual data collected during future
groundwater monitoring to the data predicted by-hydrogeologic
models. The evaluation shall be conducted on four indicator
compounds. A statistical comparison of the actual data to the
theoretical data shall be conducted using the nonparametric
distribution free signed rank test of wilcoxon with a 95 percent
significance level as described in Nonoarametric statistical
Methods (by Hollander and Wolfe, published in 1973 by John Wiley,
on pages 26-38). In summary, the rank test determines whether
the trend established by actual data falls below the trend
established by the theoretical data. If the trend for the actual
data does not fall below the trend for the theoretical data as
determined by the rank test, active restoration shall be
implemented. All compounds must pass the rank test. If one
compound fails the rank test, then active restoration shall be
implemented. In addition to requiring active restoration if
natural attenuation is not restoring the groundwater at a rate
predicted by modeling or faster, the selected remedy also
requires active restoration of the groundwater and/or long-term
monitoring of the surface water and sediments if necessary to
protect Tarkiln Brook. An example of the test has been provided
in Appendix D of the ROD using the data collected during the RI
for benzene. EPA believes that this approach eliminates any
vagueness in the trigger for active remediation as it relates to
groundwater contamination. .
XIII.
STATE ROLE
The Rhode Island Department of Environmental Management has
reviewed the various alternatives and has indicated its
disapproval of EPA's selected remedy for the site. The state,
having reviewed the RI and RI Addendum, FS and FS Addendum and
the Proposed Plan, believes that the selected remedy is
inconsistent with the Rhode Island Groundwater Protection Act.
The Act contains language that sets goals of restoration and non-
degradation of groundwater. The state maintains that such policy
statements have been consistently interpreted to require active
restoration of .degraded groundwater resources. The state thus
contends that this policy of active restoration should be an ARAR
for the Site.
EPA has thoroughly reviewed the state's position.
-------
ROD DECXSXON SUMMARY
Western Sand' Gravel site
page 538
eligible to be a state ARAR, a state requirement must be legally
enforceable~ EPA does not believe that the state's policy is
legally enforceable, and thus it cannot be an ARAR for this site.
A more thorough discussion of this issue is contained in the
Responsiveness summary, response to Comment 5 in Part II of
section ~II. A copy of the State's declaration of non-
-------
,
.~
Figure 1 -
Figure 2 -
Figure 3 -
Figure 4 -
Figure 5 -
Figure 6 -
Figure 7 -
Figure 8 -
.
APPENDIX A
RECORD OF DECISION
WESTERN SAND & GRAVEL SITE
LIST OF FIGURES
site Location Map
site Features Map
Piezometric Contour .Map (Data from Deep Overburden
Wells, February 1989)
Current Areal Extent of contamination in Overburden
Aquifer
CUrrent Vertical Extent of contamination in
Overburden Aquifer
Potential Historical Maximum Extent of contamination
Area of Access Restrictions
-------
Ii
GEORGIA VILLE QUADRANGLE
RHODE ISLAND-PROVIDENCE CO.
.1.57'30'"
SCAlE
o 1000 2OCIO
.-- -~-=- -.
SITE
.
..~.. c.~i
i'
I.". ..
158"'\.$ ; '..J.
\ t ii...\.s
~
u~~r~.'o ""0 '4I1S "AG"('< "0.'"
.......r8()tf A' t'r-.,(- ".. ~"f'!"
*
FEET
Jj
:GURB 1
.~BSTBRN SAND , GRAVEL
SITE LOCMION HAP
-------
~
+
+
~
II ,,,' .
\~"'''' ...., ........ R, KilN S' ROO'v .. "",
-......."'..-....--......., . "
"""~',
~O~---:--"'-"'''''
. ~~ '~,
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.'
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Q 0 . .
~ 7_... CJ,
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\\ 0 \
\' '
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~ ~~ :' ...,
. '>, ,. I \
"fr~.' A !
..~" () ~. V i
~. I
~~ ..r.:l \
~~ ~ ,
// '
FIGURE 2
WESTERN SAND' GRAVEL SITE
SITE FEATURES MAP
i
~
<)
o 100 200
I
400
SCAlE IN F'EIr
1/.
II
-.-_......_-
,.
-------
'W
w
.C-1
.:1.D TO'" u~(.
HOI\~ ~.. ~-UN(
-1ifUu. v....... W""
I!IJ ." ,
.n-2
..--
+
-----
....---------
.smo
()
+
<>
LEGEND
. PHASE I OR a..OSURE
MONITORING „If:LLS
A sc- SlREAU CAUGES
A STR- SlREAU SANPUNC LOCA llai
. HISTORIC YIn1.
. PHASE II „If:LLS
. PIEZOMETERS
SLATERSWJ.£
R£SERYQR
~
Mininum Extent of Pl
~
+
<>
SCAI..£ IN f'EET
/)
C:::J
FIGURE 3
WESTERN SAND , GRAVEL SITE
PIEZOMETRIC CONTOUR MAP
(Data from Deep OVerburden
February 1989)
Wells,
o tOO 200
I
400
~
-------
FIGURE 4
WESTERN SAND & GRAVEL SITE
CURRENT AREAL EXTENT OF
CONTAMINATION IN OVERBURDEN AQUIFER
Slatersville Reservoir
@
I Site
.....................
Po \.""~ ..........
~~ .......
..... 0
.................
......-
.-
!
I
I
!
i
I
j
.j
.1
I
"'
.
I
I
I
I
I
I
!
Note: ppb - pa/1$ per b,.lrlOn.
The Safe Drinking ~atet' Act
Maximum Contaminant Level
(UeL) for OIUI of the most
abundant sit. contaminants.
TeE, is 5 ppb.
Legend
Drawing Not to Scale
I -:. "'1 WeUands
-
Western Sand
& Gravel Cap
--@- Current Total VOC
Plume 1988-89 In
Overburden
Aquifer
-------
v
\~
"
--------......,
"-
\
,
11-3
8&. --
~
-
ID
. O~BUROEH
~.
--
....-
....
ILl.&.
...... - a..l:=!
WIDL _f
.
--<:!!)-tnL... -- 8IUW
<91l1li."" _...~..
m ...... ~ M'/"""'1)
WlDLll A. A..-..'
- ".18&.__.......
SEPTEMBER, 1988
FIGURB 5
WESTERN SAND , GRAVEL SITE
CURRENT VERTICAL EXTENT OF .
CONTAMINATION IN OVERBURDEN AQUIFER
NORTH-SOUTH
-------
FIGURE 6
WESTERN SAND & GRAVEL SITE
POTENTIAL HISTORICAL MAXIMUM
EXTENT o.,F CONTAMINATION
.___.._e.
Slatersville Reservoir
\
.
\
,
,
.
,
,
\ ..-
" .....-
.1.............
". .
(0
j
I
1
i
,
t
i
!
I
()
.%
as\g
C'~
~\~
~.~
~\~
t':.~
~\ffi
-4.6
~\~
C\~
~.~
\11'
Legend
Drawing Not to Scale
l...... ...~ WeUands
-
Western Sand
& Gravel Cap
((f!jJ"
.",...::../....;
.....~:;..~:...
estimated ~
maximum extent of
contamination.
~ Historic
Groundwater
Volatile Organics
Plume
-------
.
FIGURE 7
WESTERN SAND' GRAVEL SITE
AREA OF ACCESS RESTRICTIONS
.. --
. ',.,:".:. <.\/,,;.
@
Legend
Drawing Not to Scale
I ...~ "'1 Wetlands
-r--
-- \
Approx.
property lines
,--
- Area of
access
restrictions
{8
Western Sand
& Gravel Cap
-------
------
FIGURE 8
WESTERN SAND , GRAVEL SITE
ACTIVE RESTORATION PROCESS
..-- --.- --,
: pH adjust if :
I necessary I
.. - - - .. - - ..
I .
Contaminated I
Groundwater .L Settling
Tank
i
\
Metals and
other solids to a
licensed disposal
facility
Groundwater
Extraction Well
~
U
Filter
o
Clean Air
~~i~ti~'::'~,{:~:~:
." ,". I'a.r, ,'.
.: ':'.P..fUi's.lj', ,,':.
..::,~.~. ,.",::
.::.,'~: .'. :::'
':.'A'v~'r.bfjt:.
'.:'.::.:.~v..t:!,~:,:',:.i
:'.~~~!l':,
:::.:::.:::.:::.:::"::: .
Air
Blower
-
r ~
::~~i1~~:~::.:
:""~"':"
,::,~p. .~.:'::'
,~',':~~~:::,
'':~tb~~'' Storage
" """$:'
:l~~t~, :~ Tank
':,,'s ,":,
::rtmovaj)'~
, ,q""" ,
...'",".,,',.,',',",'.
....... .J
Clean water
discharged to
Tarkiln Brook
.
.....
l ~
-------
..,\' .~
Table 1 -
Table 2 -
Table 3 -
Table 4 -
Table 5 -
Table 6 -
Table 7 -
Table 8 -
Table 9 -
Table 10 -
Table 11 -
Table 12 -
Table 13 -
Table 14 -
Table 15 -
Table 16 -
- ,
.
APPENDIX B
RECORD OF DECISION
WESTERN SAND , GRAVEL SITE
LIST OF TABLES
Overburden Groundwater VOCs Detected
Overburden Groundwater - SVOCs Detected
Overburden Groundwater - HSL Metals Detected
Bedrock Groundwater - VOCs and SVOCs Detected
Surface Water - VOCs, SVOCs and Metals Detected
Sediments - VOCs, SVOCs and Metals Detected
Chemicals of Concern for Groundwater
Chemicals of Concern for Surface Water and Sediments
Assumptions Used in Exposure Calculations
CUmulative carcinogenic Risk Estimates and Hazard
Indices, Ingestion - Groundwater
cumulative Carcinogenic Risk Estimates and Hazard
Indices, Dermal Contact and Ingestion - Surface
Water '
Cumulative carcinogenic Risk Estimates and Hazard
Indices, Dermal Contact - Sediments
Alternatives Screened during Feasibility Study
Alternatives Evaluated during Detailed Analysis
Selected Groundwater Interim Cleanup Levels
Applicable, Relevant and Appropriate Requirements
-------
.
TABLE 1
, WESTERN SAND , GRAVEL SITE
:., OVERBURDEN GROUNDlA'l'ER - VOCS DB'l'BC'rED
.- -
Geometric
Sample Number .: -Maximum Mean
Parameter(ug/I) Total of Detects Cone. Cone.
Volatile Organics Detected
Acetone 42 9 1400 1.1
Benzene 210 18 47 0.7
2-Butanone 42 2 600 0.9
Chlorobenzene 210 27 370 0.8
Chloroform 210 II 60 0.6
Chloromethane 210 I 16 0.5
1,1- Dichloroethane 210 47 160 1.0
1,2- Dichloroethane 210 I 3 0.5
1,1- Dichloroethene 210 1 11 0.6
1,2 - Dichloroethene 210 86 760 1.7
Ethylbenzene 210 17 610 0.7
Methylene Chloride 210 77 280 .0.8
4-Methyl-2-Pentanone 42 2 290 0.9
Tetrachloroethene 210 33 64 0.8
Toluene 210 22 2300 0.9
1,1,1- Trichloroethane 210 40 280 1.0
1,1 ,2- Trichloroethan~ 210 I 2 0.5
Trichloroethene 210 50 200 1.3
Vinyl Chloride 210 30 430 0.9
Xylene 210 24 1600 0.9
. Proposed
.. MCL for total trihalomethanes
Criterion D')t available
-------
TABLE 2
I WESTERN SAND , GRAVEL SITE
\. OVERBURDEN GROUNIMA!l'ER - SVOCs DETECTED
.,'
Geometric
Sample Number Maximum Mean
Parameter (ug/I) Total of Detects Cone. Cone.
Semi-volatile Organics Detected
Benzoic Acid 24 3 69+ S.6
4- Methylphenol 24 3+ 1.0
Isophorone 24 4 20+ 1.4
Bis(2 - Ethylhexyl)Phthalate 24 IS 30+ 2.3
1.2-Dichlorobenzene 24 7+ 1.1
Di-n-octyl Phthalate 24 4+ 1.0
Naphthalene 24 2 8+ 1.1
N - Nitrosodiphenylamine 24 3+ 1.0
(
2- Methylnaphthalene 24 2 9+ 1.1
1,2,4- Trichlorobenzene 24 3+ 1.0
Di-n-butylphthalate 24 4+ 1.0
. Proposed
Criterion not available
+ Maximum concentration was estimated below the practical
Quantitative level
-------
.
(
TABLE 3
WESTERN SAND , GRAVEL SITE
,,:., OVERBURDEN GROUNDiMER - HSL IIB'l'ALS DETECTED
"
Geometric
Sample Number Maximum Mean
Parameter (wg/I) Total of Detects Cone. Cone.
HSL Metals Detected
Aluminum 18 4 '13.100 71
Barium 18 15 321 68
Cobalt 18 S5 11
Copper 18 40 10
Lead 18 13 17 1.6
Nickel 18 3 144 25
Silver 18 3 29 12
Zinc 18 17 269 25
(
. Proposed
Criterion not available
-------
.
TABLE 4
WESTERN SAND , GRAVEL SITE
BEDROCK GROUNIMATER - VOCs AND SVOCs DE'l'EC'l'ED
.'
Parameter (ua/l)
Volatiles
. . *
Max1mum Concentrat10n
Detected in Wells
C-4B 1I-3B
Chloromethane
Vinyl Chloride
1,1-Dichloroethene
1,1-Dichloroethane
1,2-Dichloroethene
1,2-Dichloroethane
Chloroform
1, 1, 1-Trichloroethane
Trichloroethene
Benzene
Tetrachloroethene
Toluene
Chlorobenzene
Ethylbenzene
Xylene
Acrolein
ND
2
ND
2
2
ND
ND
ND
1
ND
5
9
7
7
13
ND
2
38
1
77
22
2
4
3
31
26
25
110
17
290
198
11
Semi-Volatiles
Isophoron
NA
4
* Based on four rounds of data collected during the RI
(May 1988 - March 1989)
ND - Not detected
-------
.
TABLE 5
WESTERN SAND , GRAVEL SITE
SURFACE WATER - VDCs, SVOCs AND HE'l'ALS DETECTED
"
..
1 ..- 1 1 2 . 2 1 1 1
Volatiles STR1 5TR2 STR3 SUPL1' SUPL11' STRUt STRI.8M STR5
Acetone 2 3.5 2.5 7.5 5.5 5 1..5
8enzene 29 16 1
2-8uunone 2
CM orobenzene 52 23 2 3
1, 1-0ichtoroetnene 120 '69 3 3
1,2-0iChloroetnane 2 1
1, 1-0ichtoroetnene 1
1,2-0iChtoroethene 71 1.1 4. I.
EthylbenZene 3 3
Methylene Chloride 2.5 0.5 0.5
Tetrechloroethene 3 2
Toluene 390 190 9 9
1,1, 1-Trichloroethene 57 35 2 2
Trichloroethene 3 3
vinyl Chloride 51 55
xylene - t.t. 0 180 12 13
Semivolatiles
I sophrone at 2 ug/l in SUPL1 (August 1989) was the only semi volatile detected in the stream
Selected Metals.. Sn1 STR3 SUPL HI SUPL1" STR5
Aluainun <100 <100 <100 102 <100
Ant imany <10 <10 <10 <10 <10
Arsenic <5 <5 <5 <5 <5
8ariun <50 <50 111 129 <50
Berylliun <5 <5 <5 <5 <5
ta~iun . <5 <5, <5 <5 <5
Chromiun <10 <10 <10 <10 <10
Cobalt <20 <20 <20 <20 <20
Copper 69 t.t. 30 26 '3
Lead <2 <2 <2 <2 <2
Mercury <0.2 <0.2 <0.2 <0.2. <0.2
Micltel <'0 <4.0 <'0 <'0 d.O
Seleniun <2 <2 <2 <2 <2
Silver <10 <10 <10 <10 <10
Thall iun <2 <2 <2 <2 <2
Vanedi", <50 <50 <50 <50 <50
Zinc 58 25 .. .);) ,. --.. ~y' - ._" '8
. Stre.. sampte results for (1) September 1988 and (2) August 1989
.. Calci"" ugnesiU8. iron. potassiua, eanganese. and sodi", not included
due to negligibte toxicity.
. SUPL1 and SUPL11 are duplicate samples at location STR-SUPL end
STR'A and STR" are duplicate samples at location STR-'.
-------
.
( ~ 'f
TABLE 6
WESTERN SAND , GRAVEL SITE
SEDIMENTS - VOCs, SVOCs AND METALS DETECTED
1 . 1 1 2 . 2 1 1
Volatiles SED1 SED2 SED3 SUPl1l SUPl11' SED'A SED'
Acetone 27 50 2'.5 19 22
Chtorofo"" 1.5 3
"ethylene chloride 26 10 12 17 63 21.5 13.5
Tetrachloroethene 120
Semivolatites SED 1 SED3 SUPl1 SUPl111 SED5
Acenaphthylene 110
Anthracene 93
Benzoic Acid 230 83
Benzo(a)Anthracene '30
Benzo(a)Fluoranthene 550
Benzo(b)Fluoranthene 1000 '8
BenZO(9,h,i)Perylene '30
8enzo(k)Fluoranthene 1000 '8
bis(2-chloroisopropyl)Ether 61.
bis(2.Ethylhexyl)Phthalate 72 59 65
Chrysene '60
Fluoranthene 720 '9 67
Ideno(1,2,3-cd)Pyrene '20
Phenanthrene 360
Pyrene 700 53
Selected "etlls.. SE01 SE03 SUPl1# SUPl11. SED5
AIUllinun' 17'5011: 159011: Ji.6011: 330011: 192011:
Ant imony <100 <100 <20 <20 <100
Arseni c 228 2'6 2170 997 36/0
BariUII 7630 '600 21100 21300 5380
Beryl I iUII 8l. 78 3/.9 262 10'
C.aa i UII 1010 <50 533 '55 7'53
Chromiua 1620 906 3920 3020 3870
Coba I t <200 <200 <200 <200 <200
Copper 1370 <200 7610 '1.6() <200
lead 29500 10500 23200 23100 15100
Mercury <100 <100 <100 <100 <100
Nickel l.68O 2890 7260 6890 3680
SeleniUII c20 <20 <20 <20 26
Silver <10 <10 <10 <10 <10
Thall iUII <20 <20 53 '0 <20
VanadiUII 3650 1510 1370 7170 3l.50
Zinc '8800 10500 "300 13700 2'900
. Sedf..,t Ulaple results for (1) Septeatler, 1988 and (2) August 1989
.. Calciua, -.gnesiUII, iron, potaSSiUII, llanganese and sodiun not included
not included due to negligible toxicity.
IC . 1000
. SUPl1 and SUPltt are duplicate ~.es _t' loealion SiR'SUPl.
-------
.
TABLE 7
WESTERN SAND AND GRAVEL SITE
CHEMICALS OF CONCERN FOR GROUNIMATER
Volati~s
Metals
Acrolein
Acetone
Benzene
Bromomethane
2-Butanone
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
l,l-Dichloroethane
1,2-Dichloroethane
l,l-Dichloroethene
l,2-Dichloroethene
trans-l,3-Dichloropropene
Ethylbenzene
Methylene chloride
4-Methyl-2-pentanone
l,l,2,2-Tetrachloroethane
Tetrachloroethene
Toluene
l,l,l-Trichloroethane
l,l,2-Trichloroethane
Trichloroethene
Trichlorofluoromethane
xylene
Vinyl chloride
Aluminum
Arsenic
Barium
Beryllium
Cadmium
Chromium
Cobalt
Copper
Lead
Nickel
Silver
Zinc
Semivolatiles
Benzoic acid
bis (2-ethylhexyl) Phthalate
l,2-Dichlorobenzene
l,4-Dichlorobenzene
Di-n-octyl Phthalate
Di-n-Butyl Phthalate
Isophorone
4-Methylphenol
2-Methylnaphthalene
Naphthalene
1,2,4-Trichlorobenzene
-------
.
TABLE 8
. WESTERN SAND AND GRAVEL SITE
CHEMICALS OF CONCERN FOR SURFACE WATER AND SEDIMENTS
-
SEDIMENT
SURFACE WATER
Volatiles
Volatiles
Acetone
Methylene chloride
Tetrachloroethene
Semivolatiles
Acetone
Benzene
2-Butanone
Chlorobenzene
1,1-Dichloroethane
1,2-Dichloroethane
1,1-Dichloroethene
1,2-Dichloroethene (total)
Ethylbenzene
Methylene chloride
1, 1, 1-Trichloroethane
Tetrachloroethene
Toluene
Trichloroethene
Xylene
Vinyl chloride
Benzoic Acid
Metals
Arsenic
Barium
Beryllium
Cadmium
Chromium
Copper
semivolatiles
Isophorone
Metals
Barium
-------
.
TABLE 9
WESTERN SAND AND GRAVEL SITE
.~ ASSUMPTIONS USED IN EXPOSURE CALCULATIONS
"
Ingestion - Groundwater
Ingestion Rate (liters/day)
Body weight (kg) - adult
2
70
Dermal contact and Ingestion - surface Water
Skin surface area (cm2)
Exposure time (hours/event)
Exposure frequency (events/yr)
Exposure duration (yrs)
Ingestion rate (liters/event)
Body weight (kg) - child
5633
2.6
21
9
0.05
40
Dermal contact - Sediment
Skin surface area (cm2)
Adherence factor (mg/cm2)
Absorption factor-metals, organics
Skin coverage fa~tor
Exposure frequency (events/yr)
Exposure duration (yrs)
Body weight (kg) - child
5633
0.5
0.01, 0.5
0.5
21
9
-------
.
TABLE 10
.. - WESTERN SAND' GRAVEL SITE
.'
CUIfULMIVB CARCINOGENIC RISK ESTIMATBS AND HAZARD INDICES
INGBSTION - GROUNIMATBR
Well Cancer Risk Estimates Hazard Index
Groupinqs Avq RHE Avq RHE
1 On-site 3X10-4 3X10-2 3X10-l 5xlOO
overburden
2 On-site lX10-4 3X10-2 3X10-l 5X100
overburden
& bedrock
3 Off-site 7xlO-s 3xlO-3 2X10-l lX100
overburden
4 Off-site 7X10-s 3X10-3 2xlO-l lX100
overburden
& bedrock
5 Residential 4X10-6 2X10-s lX10-2 7X10-2
overburden
6 Residential 2X10-6 2xlO-s lX10-2 lX10-l
bedrock
7 Residential 4X10-7 5XIO-6 <5XIO-4 lXlO-2
-------
TABl. .11
WESTERN SAND , GRAVEL SITE
CUMULATIVE CARCINOGENIC RISK ESTIMATES AND HAZARD INDICES
DERMAL CONTACT AND INGESTION - SURFACE WATER
Reasonable Reasonable Maximum
Chemical Potency F~ctor Dermal Maxinun Cone. Maximum Exposure Cancer Risk
(mg/kg/day)-1 Permeabi~ity ug/L mg/kg-day
Constant Seep Stream Seep Stream Seep Stream :,
CARCINOGENIC RISK
Benzene 2.9£-02 1.6£-01 2.9E+01 1.0E+00 1.3E-05 4.4E-07 3.SE-07 1.3E-08
1,1-Dichloroethane 9.1E-02 1.0E-01 1.2E+02 3.0E+00 3.4E-05 8.4E-07 3.1E-06 7.6£-08
1,1-Dichloroethene 6.0E-01 1.0E-01 1.0E+00 NO 2.8E-07 1.7E.07
1,2-0ichloroethane 9.1E-02 1.0E-01 2.0E+00 NO 5.6E-07 5. 1E-08
I sophorone 4.1E-03 5.0E-03 2.0E+00 NO 4.6E-08 1.9£-10
Methylene chloride 7.5E-03 1.0E-01 ND 2.5E+00 NO 7.0E-07 5.3E-09
Tetrachloroethene 5.1E-02 2.0E-01 3.0E+00 NO 1.7E-06 8.4E-08
Trichloroethene 1.1E-01 1.0E-01 3.0E+00 NO 8.4E-07 9.2E-08
Vinyl chloride 2.3E+00 1.0E-01 5.5E+01 NO 1.5E-05 3.5E-05
Total 4E-05 9£-08
Chemical Oral Reference Dermal Maximum Cone. RME Exposure RME Huard Index
Dose Permeability ug/L mg/kg.day
mg/kg/day Constant Seep Stream Seep Stream Seep Stream
NONCARCINOGENIC HAZARD
Baril.l1l 5.0E-02 3.0E-02 1.3E+02 NO 3.7E-04 7.4E-03
1,2-0ichloroetheneCtotal) 2.0E.02 1.0E-01 7. 1E+01 7.1E+01 6.3E-04 3.5E-05 3.1E-02 1.8E-03
Chlorobenzene 2.0E-02 1.0E-01 5. 2E+01 5.2E+01 4.6E-04 2.7E-05 2.3E-02 1 .4E -03
Toluene 3.0E-01 5.0E-02 3.9E+02 3.9E+02 1.8E-03 4.1E-05 5.9£.03 1.4E-04
1,1-0ichloroethane 1.0E-01 1.0E-01 1. 2E +02 1.2E+02 1.1E-03 2.7E-05 1.1E-02 2.7E-04
Acetone 1.0E-02 5.0E-03 7.5E+00 7.5E+00 5.4E-06 3.6E-06 5.4E-04 3.6E-04
1,1,1-Trichloroethane 9.0E-02 6.0E-03 5.7E+01 5.7E+01 4.6E-05 1.6E-06 5.1E.04 1.8E-05
Tetrachloroethene 1.0E-02 2.0E-01 3.0E+00 3.0E+00 5.2E-05 5.2E-03
Ethylbenzene 1.0E-02 1.0E+00 NO NO 2.6E-04 2.6£.02
Xylene 2.0E+00 8.0E-02 4.4E+02 4.4E+02 3. 1E -03 9.3E-05 1.6E-03 4.7E-OS
1.1-0ichloroethene 9.0E-03 1.0E-01 1.0E+00 1.0E+00 8.8E-06 9.8E-04 .
. .
Methylene chloride 6.0E-02 1. DE -01 ND ND 2.2E-05 3.7E-04
2-Butanone 5.0E-02 5.0E-03 2.0E+00 2.0E+00 1.4E-06 2.8E-05
Isophorone 2.0E-01 5.0E-03 2.0E+00 2.0E+00 1.I,E-06 7.0E-06
-------
TABLE 12
WESTERN SAND' GRAVEL SITE
CUMULATIVE CARCINOGENIC RISK ESTIMATES AND HAZARD INDICES
DERMAL CONTACT - SEDIMENTS
Reasonable Reasonable M8II.
Chemical Potency Factor Absorpt I on Maxinun Cone. Maxlnun Exposure Cancer Risk
(,,/kg/day) -1 factor ug/kg mg/kg-day
Seep Stream Seep Stream Seep Stream
CARCINOGENIC RISK
Tetrachloroethene 5.1e-02 5.0E-01 1.2E+02 NO 3.1E-09 ,1.6E-10
Methylene chloride 7.5E-03 5.0E-01 6.3E+01 2.6E+01 1.6E-09 6.8E-10 1.2E-11 5.1E-12
Total 1.7E-10 5.1E-12
Chemical Oral Reference Absorpt ion Maxinun Cone. RME Exposure RME Hazard Index
Dose Factor ug/l mg/kg-day
mg/kg/day Seep Stream Seep Stream Seep Stream
NONCARCINOGENIC HAZARD
Acetone 1.0E-01 5.0E-01 5.0E+01 2.7E+01 4.1E-08 2.2E-08 4.1E-07 2.2E-07
Methylene chloride 6.0E-02 5.0E'01 6.3E+01 2.6E+01 5.2E-08 2.1E-08 8.7E-07 3.5E-07
Tetrachloroethene 1.0E-02 5.0E-01 1.2E+02 NO 9.9E-08 9.9E-06
Benzoic acid 4.0E+OO 5.0E-01 2.3E+02 NO 1.9E-07 4.8E-08
Arsenic 1.0E-03 1.0E-02 2.2E+03 3.6E+02 1.8E-07 3.0E-OS 1.8E-04 3.0E-05
Bariun 5.0E-02 1.0E-02 2.1E+04 7.6E+03 1.7E-06 6.3E-07 3.4E-05 1.3E-05
Berylliun 5.0E-03 1.0E-02 3.5E+02 1.0E+02 2.9E-08 8.5E-09 5.8E-06 1.7E-06
Cadmiun 1.0E-03 1.0E-02 5.3E+02 1.0E+03 4.4E-OS 8.3E-08 4.4E-05 8.3E-05
Chromfun 5.0E-03 1.0E-02 3.9E+03 3.9E+03 3.2E-07 3.2E-07 6.4E-05 6.4E-05
Copper 3.7E-02 1.0E-02 7.6E+03 1.4E+03 6.3E-07 1. 1E-07 1. 7E -05 3.0E-06
Total 3.6E-04 1.9E-04
-------
.
(
TABLE 13
WESTERN SAND , GRAVEL SITE
ALTERNA!l'IVES SCREENED DURING FEASIBILITY STUDY
,-
General Response A lternaH ves
Actions Remedial Technologies 2 3 4 5 6 7
No Further Action .
InstituUonal Actions Groundwater Monitoring .
Temporary Access Restrictions ..
Use Restrictions
Property Acquisition
Temporary Alternate ..
Water Supply
Well Head Treat.ent
Use of Existing
Supply System
Alternate Water Source
Col lection Extraction Wells
Treatment Onsite: Solids Removal! .. ..
Preci pi tat ion
Air Stripping
" Carbon Absorption
( Offsite: PON
Private Facility
Discharge Onsite: local Surface Water .
Groundwater .
Offsite: POTW
.. Any of the technologies identified in the group can be used for the alternative.
-------
f
TABLE 14
WESTERN SAND' GRAVEL SITE
ALTERNATIVES EVALUATED DURING DETAILED ANALYSIS
Groundwater
Restoration
Controls
. Natural Active
Access Well Head
Groundwater
Monitoring
. .
Surface Water
& Sediments'
1
~
2
~
./
3
./
.I
4
I
"*
.I.
or
.I
.I
5
.1**
.I
or
.I
6
*;~*
./
./
*
DIscharge to Tarklln Brook .
**
'*** DIscharge to groundwater wIth excess flow t? Tar~rrn Brook
Contingent active restoration
./
./
.I
./
./
.I
./
.
-------
TABLE 1:)
WESTERN SAND' GRAVEL SITE
SELECTED GROUNIMATER INTERIM CLEANUP LEVELS
Chemlcel..
(Voletlle Orgenlcs)
Acetone
Benzene
2-Butenone
Chlorobenzene
Chloroform.
Chloromethene
1,1-0Ichloroethene
1,2'Olchloroethene
1,1-0Ichloroethene
1,2-0Ichloroethene (1)
Ethylbenzene
Methylene Chloride
4-Methyl-2-pentenone
Tetrechloroethene
Toluene
trens-1,3-0Ichloropropene
1,1,1-Trlchloroethene
1,1,2-Trlchloroethene
Trlchloroethene
Xylene
Vinyl chloride
Bromomethene
1,1,2,2-Tetrechloroethane
Chloroethene
Acrolein
Trlchlorofluromethane
Reference
Dose(orel)
(mg/kg/day)
1.0E-01
5.0E-02
2.0E-02
1.0E-02
1.0E-01
9.0E-03
2.0E-02
1.0E-01
6.0E-02
5.0E-02
1.0E-02
2.0E-01
3.0E-04
9.0E-02
4.0E-03
2.0E+00
1.4E-03
3.0E-01
Cerc. Potency Int Cleenup
Fector(orel) level
. (mg/kg/day)-1 (mg/l)
2.9E-02
3.5E+00
5.0E-03
1.8E+00
1.0E-01
1.0E-01
3.0E-03
3.5E+00
5.0E-03
7.0E-03
7.0E-02
7.0E-01
5.0E-03
1.8E+00
5.0E-03
1.0E+00
5.0E'03
2.0E-01
3.0E-03
5.0E-03
1.0E+01
2.0E-03
3.5E-02
1.0E'03
1.4E+01
6.1E-03
1.3E-02
9.1E-02
6.0E-01
7.5E-03
5.1E-02
1.8E-01
5.1£-02
1.1E-02
1.9E+00
2.0E-01
1.0E+01
Basis
HB
HCl
HB
PHClG
HCl
RB
HB
HCl
HCl
PHClG
PHClG
HCl
HB
HCl
MCl
Dl
HClG
PMClG
HCl
PHClG
MCl
HB
Dl
HB.
CNA
HB
Cancer
Risk
level
4.2E-06
1.8E-05
1.1E-06
1.3E-05
1.2E-04
1.1E-06
7.4E-06
2.6E-05
5.0E-06
1.6E-06
1.1E-04
Noncancer Noncancer
HaurdTerget
Index Endpoint
1.0E+00 liver, kidney
. 1.0E+00 fetotoxiclty
1.5E-01 liver, kidney
2.9E-01 liver
1.0E+00 none
2.3E-02 liver
1.0E-01 blood
2.0E-01 liver, kidney
2.4E-03 liver
1.0E+00 liver, kidney
1.5E-02 liver
1.5E-01 organ weight
4.8E-01 organ weight
6.4E-02 liver
2.2E-02 ciinicil chem.
1.5E-01 body weight, mortality
7.3E-01 stomach
1.0E+00 blood, CNS
9.7E-01 mortality
-------
TABLE 15 - CONTINUED
WESTERN SAND , GRAVEL SITE
SELECTED GROUNIMATER INTERIM CLEANUP LEVELS
Cheml cal Reference Carc. Potency Int Cleanup Basis Cancer Noneaneer Noncaneer
Oose( ore l> FactorCoral) level Risk Hazard Target ".
C 1IIg/ k 1/ day) Cmg/kg/day) -.1 Cmg/l) level Index Endpoint :.
CSemlvolat I lei)
Benzoic acfd 4.0E+00 1.4E+02 HB 1.0E+00 Irritation, malais
bIIC2-ethythexyt)phthalate 2.0E-02 1.4E-02 4.0E-03 PMCl 1.6E-06 5.8E-03 tlver
rlophorone 2.0E-01 4.1E-03 8.4E-03 RB 1.0E-06 1.2E-03 kidney
2-Methylnaphthalene CNA
4-Methylphenot 5.0E-02 1.8E -01 HB 1.0E-01 neurotoxicity
Napthal.". 4.0E-OS 1.4E-01 HB 1.0E+00 body weight
N-nltrosodlphenylamlne 4.9£-03 1.0E-02 Ol 1.4E-06
1,2,4-Trlchtorobenzene 1.3E-03 9.0E-03 PMClG 2.0E-01 blood
1, 2-D Ichlorobenlene 9.0E-02 6.0E-01 PHClG 1.9E-01 liver
t,4-Dlchlorob,ntene 2.4E-02 7.5E-02 HClG 5.2E-05
Ol-n-octyt phthaLate 2.0E-02 7.0E-01 HB 1.0E+00 liver, kidney
Ol-n-butyt phth~late 1.0E-01 4.0E-03 PHCl 1.2E-03 mortality
CMetals)
Aluninun 5.0E-02 SHCl
Barlun 7.0E-02 1.0E+00 PHClG 4.1E-01 blood pressure
Cobalt CNA
lead 5.0E-03 PHCl
Nickel 2.0E-02 1. OE -01 PHClG 1.5E-01 body, organ weight
Sit ver 3.0E-03 9.0E-02 SHCl 8.TE-01 argyria-skin
Zinc 2.0E-01 5.0E+00 SHCl 7.3E-01 blood
Total 3.7E-04 ~eight Change: 6.1E+00
Liver: 4.1E+00
Kidney: 2.5E+00
Blood: 2.4E+00
-------
TABLP "5 - CONTINUED
WESTERN ND' GRAVEL SITE
SELECTED GROUNIMMER INTERIM CLEANUP LEVELS
NOTES
MCl - Maximum Contemlnant level
PMCl - Proposed MIXI... Contemlnar t Level
MCLG - Maximum Cont..lnant level Goal
PMCLG - Proposed MaxlllUll Contemlnar'lt level Goal
SMCl - Secondary Maxlnun Contemlna.,t level
RB . Risk Based (carcinogens)
HB - Hazard Based (noncarclnogens)
HB. - The clean-up level for chloroethane Is based on the RfD for chlorobutane.
A structural similarity is assumed.
CNA - Criteria Not Available
RSD - Risk Specific Dose
Dl - Detection limit
Chloroform- - The MCl for total trlhalomethanes was used for chloroform.
:.
(1) Since the specific 1,2-Dlchlorothene Isomer was not identified In the RI Report, the MCl for the
cis" isomer Is cited. The cleanup level may be overprotective If the isomer detected Is the "trans" Isomer.
-------
TABLE 16
WESTERN SAND' GRAVEL SITE
APPLICABLE, RELEVANT AND APPROPRIATE REQUIREMENTS
(ARARs)
ARAR
:,
Sp.ct fi c
Type
federal-Contaminant.
Safe Drinking
Water Act
a. Haximum
Contaminant
Levels (MCLs)
b. Haximum
Contaminant level
Goah (HClGs)
c. Secondary Haxlmum .
Contanu.nant Levels
EPA Health Advisories
Heal th Effects
Assessments
Contaminant
Contami nant
Con t.aml nan t
Con taml nan t
lega 1 C I tatl on
Potent. ia 1 Legal
Classification
Explanat.ion of
Class i fI cat. ion
Applicabilit.y to
rs Opt.ions
40 erR 141
40 crR 141.50-51
40 erR 143
To 8e Considered
To 8e Considered
ReJevant. and
Appropriate
Relevant and
Appropri ate
Relevant and
Appropriat.e
Applicable
Relevant and
Appropriat.e
Enforceable standards
for public drinking water
water supply systems
(at. least 25 persons)
Non-enforceable healt.h
goals for public water
Non-enforceable guidelines
for public drinking water
systems
Non-enforceable guidelines
for public water supply
systems
Non-enforceable toxicity
data for specific chemicals
for use in public healt.h
assessments. Also to be
considered are Carcinogenic
Potency ractors and Refer-
ence Doses provided In the
Sup'rfund Public Health
Evaluat.lon Hanual.
HCls apply to public wat.er
systems which provide piped
water for human consumption
and are reJevant and appro-
priate to cleanup levels to
be achieved by CERCLA
. remedial actions for drink-
Ing water aquifers
Non-zero HClGs are relevant
and appropriate standards
for drinking wat.er sources.
To be considered for
remedial actions involving
groundwater monitoring,
recovery, and treatment.
To be considered where
remedial alternatives
address risk-based criteria
or standard setting for
cleanup
Also applies to dust emis-
sions, emissions during
excavat.lons, and emission
from leachate- or ground-
water treatment limits
-------
~
-
-
-
~
-
~..;-
-
-
-
-.
--:-
-
--
.-
-
-
TABLE 16 ~ ~ONTINUED
WESTERN SAND 1RAVEL SITE
APPLICABLE, RELEVANT AND- _~PROPRIATE REQUIREMENTS
(ARARs)
Spec! fi c Potential legal Explanation of Applicability to
ARAR Type legal Cltallon Class if I cali on Classification FS Opll ons
Clean Water Ad
a. Water Qual Hy Contalllinant EPA 44/5-86-001 App1l cab 1 e Non-enforceable guidance To be considered If the~,
deveJoped under Clean Water is a discharge to a stream
Act and used by the state, that may affect aquatic;
in conjunction with a deslg- organisms or human exposure
nated use for a stream from drinking the ~ater and
segment to establish water from consuming aquatic
quality standards organisms
b. Ambient Water Contaminant. Pl 92-5000 Relevant. and Non-enforceable crlt.eria To be considered for actions
Qual Hy CrHeria Section 304(a)(1) Appropriat.e used t.o develop standards that involve groundwater
treatment and discharge to
surface water
State-Contamlnant.
Rhode Island Water Conhmi nant RIGl 46-12 Applicable Set criteria to meet Clean To be used when there Is a
Quality Standards Water Act Standards for the discharge of recovered
intended use of state waters groundwater to surface
wat.ers
Rhode Island Water Conhmi nant RIGl 46-12, Applicable Regulates restoration,
Quality Regulations enhancement, and preserva- .
tion of state waters
Federal-location
RCRA location locall on App 11 cab 1 e limitations. on where To be considered when
Requirements onsite storage treatment remedial adlons involve
or disposal of hazardous ons ite acti ons
EPA Groundwater
Protection Standard
localion
To Be Considered
EPA pot icy regarding pro-
tection of groundwater
resources for Its highest.
present or beneficial use
The aquifer beneath the
site is considered to be of
IIA Classification. The
groundwater protection
strategy requires considera-
-------
-~
.-
-.-
-.
~
-
-
-.
--
TABLE 16 - CONTINUED
WESTERN SAND' GRAVEL SITE
APPLICABLE, RELEVANT AND APPROPRIATE REQUIREMENTS (ARARs)
Potent i a 1 Legal
ChssHi catl on
Exphnatlon of
Chssi flcltion
ARAR
SpecHi c
Type
Legal CHation
Applicability to
FS Options
Federal Protection of
Wetlands Executive
Order
Location
E .0. 11990
AppH cabl e
Requires federal agencies
to take action to minimize
the destruction, loss, or
degradation of wetlands
and to preserve and enhance
the natural and beneficial
values of wetlands
The Fish and Wildlife
Coordination Act
Location
16 USC 661
AppHcable
Requirements for the modi-
fication of any body of
water
.
To be considered when
reviewin9 remedial alterna-
tives whIch may impact :,
nearby wetlands
To be considered should
remedial action potentially
impact wetlands or protected
habitats
a. The Fish and Wild- Locati on 1'6 use 142. Applicable Provide for consideration To be considered if reme-
It h Iliprovement of the i~acts on wetlands dial action could impact
Act of 1978 and protected habitats wetlands or protected
! haM ta ts
i
b. The Fish and Wild- Location ;16 USC 2902 AppH cabl e Provide for consideration To be considered if reme-
life Conservation of the impacts on wetlands dial action could impact
Act of 1980 and protected habitats wetlands or protected
-------
a
.
..
..
-
-
IA'
-
..
..
..
..
-..
..
WI8.
m8IL
--.
~
-.
TABLE 16 - CONTINUED
WESTERN SAND & GF ~L SITE
APPLICABLE, RELEVANT AND APPj, .RIME REQUIREMENTS (ARARS)
ARAR
SpecHi c
Type
. legal CHalion
pot.enHal Legal
Classi Ucalion
Explanat.ion of
C1assificat.ion
Applicabillt.y t.o
fS Opt.ions
:,
Sht.e-Loc::at.ton
Rhode Island Ground- locati on RIGl-46-13.1 To 8e Considered Est.abllshes t.he st.at.e's Prot.ect.ion and rest.oralion
Wat.er Prot.ect.ion Act. classiflcat.ion syst.em for requirement.s t.o be consider-
of 1985 groundwater resources ed when finalized
Rhode Is land locat.lon RIGl - THle 2 Appli cable Regulat.es and preserves To be considered shou1d
freshwat.er Wet.1ands swamps, marshes, and wet.- remedial act.lons pot.enlially
Act lands. Requires capacit.y affect. swamps, marshes. or
maint.enance t.o support. wet.lands
wl1dlife and act. as a buffer
zone for flood condlt.ions
[edera1-Ac::t.ion
Clean Water Ad Act I on Secti on 404 and Appllcab1e Prohibit.s discharge of App11cab1e t.o p1acement. of
40 efR Part. 230 dredged or fi11 malerlal fi11 mat.eria1 necessary t.o
int.o wat.ers of t.he U.S., const.rucl any of t.he
inc1uding wet1ands a He rna ti ves
OOT Ru1es for Ac t.i on 49 CfR Part.s Appli cab1 e Regulat.ions for t.ransport. App11cable t.o wast.es shipped
Hazardous Hat.erials of hazardous mat.erla1s offslt.e for 1aborat.ory
ana1ysis, t.reat.ment.. or
-------
.....
~
....
~
ARAR
Occupational Health
and Safety Act
The Clean Air Act
Gen.ral Pre-treatment
Regulations
State-Action
Rhod. Island Hazardous
Wash Rules and
Regulations
Rhode Island Air
Pollution Control
Regulations
Rhode Island Ai r
Pollution Control Act
Rhode Island Air Toxic
Regulations
Rhode Island Pre-
treatment Regulations
Rhode Island Pollutant
Discharg. Elimination
System Regulations
TABLB 16 - CONTINUED
WESTERN SAND' GRAVEL SITE
APPLICABLE, RELEVANT AND APPROPRIATE REQUIREMENTS (ARARs)
--
Specific
Type
Action
Acti on
Action
Actt on
Action
Action
Action
Action
Action
Underground Injection Action
Control Program
Rules & Regulations
-.
u..
....
Legal Citation
29 CFR Parts
1904. 1910. and
1926
40 CFR 50
40 CFR 403
-
--
Potential Legal
Classification
AppH cabl e
AppHcable
App H cable
Relevant and
Appropriate
Applicable
Applicable
Regulation No. 22 Relevant and
Appropriate
Relevant and
Approprt ate
Applicable
Applicable
-
~J
-
Explanation of
Classification
-
-
-
-
.
.
Applicability to
FS Options
Provides occupational safety Area applicable to onslte',
and health requirements for work performed during,
workers engaged in onsite implementation of a remedia~
field activities
Establish air emission
standards
Standard for discharge to
publicly-owned treatment
works (POTW)
Correspond to RCRA hazard-
ous waste regulations
Details the requirements
of limitations and exemp-
tions of state air emis-
sion regulations specified
substances
Outlines the policy of
preserving. protecting.
and improving the air
resources of Rhode Island
Limits the emission of
listed substances from
stationary sources
Rhode Island standards for
discharge to POTWs
Are applicable for po~entia1
releases resulting from
remedial activities
To be considered should
remedial action entail dis-
charge to POTW
To be considered with RCRA
regulations
To be considered for poten-
tial air releases resulting
from remedial activities
To be considered for poten-
tla1 air releases resulting
from remedial activities
To be considered for poten-
1ial air releases resulting
from remedial activities
To be considered should
remedial action entail
discharge to POTW
Rhode Island permit require- To be considered should
ments for discharge to state remedial action entail
surface waters diicharge to surface
waters
RequiraTIents for
underground injection
. of groundwater
Tb be considered should
ra~ial action entail
discharge to groundwater
-------
.
APPENDIX C
.. -
RECORD OF DECISION
WESTERN SAND' GRAVEL SITE
-------
.
. United States
Environmental Protection Agency
Region I
.. -
SUPERFUND
Responsiveness Summary
Western Sand & Gravel Site
Burrillville, Rhode Island.
-------
.
.. -
Table of Contents
Preface
..................... ..... .................. 1
I.
Overview of Remedial Alternatives Considered in the
Groundwater Feasibility Study and Feasibility Study Addendum,
Including the Preferred Alternative. . . . . . . . . . . . . . . . . . . . .. 2
II. Background on Community Involvement and Concerns. . . . . .. 3
III. Summary of Comments Received During the Public
Comment Period and EPA Responses. . . . . . . . . . . . . . . . . . .. 6
Part I - Citizen Comments. . . . . . . . . . . . . . . . . . . . . . . . . . .. 6
Part II - State Comments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Part III - Potentially Responsible Party Comments. . . . . . . . . . 33
IV. Remaining Concerns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Attachment A:
Formal Community Relations Activities ConduCted To Date
at the Western Sand & Gravel Superfund Site
~ . Attachment B:
-------
.
Preface
The u.s. Environmental Protection Agency (EPA) held a 3o-day comment
period from February 12, 1991 to March 13, 1991 to provide an opportunity for
interested parties to comment on the Groundwater Feasibility Study (FS) , Feasibility
Study Addendum, the Proposed Plan and other documents developed for the Western
Sand & Gravel Superfund Site (the Site) in Burrillville, Rhode Island. The FS and FS
Addendum examined and evaluated various options, called remedial alternatives, to
address groundwater contamination at the Site. EPAidentified its preferred alternative
for addressing groundwater contamination in the Proposed Plan. ~ued on February 4,
1991. All the documents for the Site were placed in the Administrative Record for
review. The Admif1istrative Record is a collection of all the documents considered by
EPA to choose the remedy for the Site. It was made available at the EPA Records
Center at 90 Canat Street in Boston, Massachusetts and at the Burrillville Town
Building at 105 Harrisville Main Street in Harrisville, Rhode Island.
"
The purpose of this Responsiveness Summary is to document EPA responses
to the questions and comments raised during the public comment period on the FS,
FS Addendum, Proposed Plan and other documents in the Administrative Record.
EP A considered all of these questions and comments before selecting the final
remedial alternative to address the groundwater contamination at the Western Sand &
Gravel Site.
I.
This Responsiveness Summary is organized into the following sections:
Overview of Remedial Alternative. Considered In The Groundwater
Feasibility Study and Feasibility Study Addendum, Including the Preferred
AItematlve - This section briefly outlines the remedial alternatives evaluated in
the Groundwater FS, FS Addendum, and the Proposed Plan, including EPA's
preferred alternative.
II.
Background on Community Involvement and Concem. - This section
provides a brief history of community interests and concerns regarding the
Site.'
III.
Summaty of Comment. Received During the Public Comment Period and
EPA Re.pon.e. - This section summarizes and provides EPA responses to
the oral and written comments received from the public during the public
comment period. In Part I, the comments received from citizens are
presented. Part II containscoi,1ments from the State. Part III summarizes
comments received from potentially responsible parties (PRPs).
IV.
Remaining Concem. - This section describes issues that may continue to be
of concern to the community during the design and implementation of EPA's
selected remedy for the Site. EPA will address these concerns during the
Remedial Design/Remedial Action phase of the groundwater cleanup process.
WESTERN SAND & GRAVEL SUPERFUND SITE
-------
.
In addition, two attachments are included in this ResponsivenesS Summary.
Attachment A provides a list of the community participation activities that EP A and the
Rhode~1sIand Department of Environmental Management (RIDEM) have conducted to
date at the Site. Attachment B contains a copy of the transcript from the informal
publiC hearing-held on February 28, 1991 in Burrillville, RI.
.
I.
Overview of Remedial Alternatives
Considered in the Groundwater Feasibility
Study and Feasibility Study Addendu~,
including the Preferred Alternative
The cleanup plan selected by EPA will restore contaminated groundwater to
target cleanup levels through natural attenuation. The remedy requires groundwater
monitoring to ensure that levels of contamination decrease to safe levels in 24 to 28
years, or sooner, as predicted by groundwater modeling. Progress at the Site will be
evaluated every 3 years for the first 9 years, and every 5 years thereafter. A
groundwater collection and on-site treatment system will be employed if natural
attenuation fails to achieve EPA's groundwater cleanup goals in the projected time
frame. The cleanup plan will use institutional controls to prevent any use of
groundwater until contaminant concentrations have decreased to safe levels.
Additional data will be collected under the provisions of the existing consent decree
with the potentially responsible parties (PRPs) to further characterize the impacts to
the bedrock system, the surface water and sediments. After reviewing the results of
these investigations, EPA will determine if it is necessary to modify the selected
remedy to include active restoration of the groundwater and/or long-term monitoring of
the bedrock system, surface water and sediments. The estimated net present worth of
the groundwater cleanup is $1.1 million if natural attenuation is allowed to clean the
aquifer. or $4 million if active treatment of the groundwater is needed.
In the Groundwater FS and FS Addendum EPA evaluated a total of six
potential cleanup alternatives, Including the preferred altemative presented in the
Proposed Plan. for groundwater contamination at the Western Sand & Gravel Sne.
The other five alternatives are described briefly below.
AItemat1v8 1: Groundwater Re8foratlon by Natural Attenuation and
Groundwater Monitoring (No Act/on) This altemative did not include
restrictions on groundwater use.
Alternative 2: Groundwater Restoration by Natural Attenuation,
Groundwater Monitoring, and Temporary Acce.. Restrictions for Potent/a I
Future Re./dent. This altemative included access restrictions for an area
larger than the area selected by EPA.
2
-------
.
Altematlve 3: Groundwater Restoration by Natura' Attenuation,
..Gfoundwater Monitoring, and Well Head Treatment 'or Potential Future
R88Ident8 This alternative inctuded the use of filters to protect potential future
residents from contaminated groundwater instead of access restrictions.
.
Altemative 4: Actlve Groundwater Restoration with Discharge to Surface
Water, Groundwater Monitoring, and Temporary Access Restrictions or Well
Head Treatment 'or Potentia' Future Resident. This alternative proposed
immediate treatment of groundwater to be continued for approximately 11 to
17 years.
"
Altematlve 5: Active Groundwater Restoration with Discharge to
Growwlwater and Surface Water, Groundwater Monitoring, and Temporary
Aceell Restrictions or Well Head Treatment for Potentia' Future Residents
Tms altemati'c'e proJXJSed immediate treatment 01 groundwater to be continued
for appt'e»:im~ 10 years.
In addition, Alternatives 1 through 5 did not provide for additional activities
after a review of the data on the bedrock, surface water and sediments.
Additional infonnation on-each of the remedial alternatives can be found in the
Record of Decision (ROD), copies of which are located in the Town Clerk's Office in
the Burrillville Town Building at 105 Harrisville Main Street in Harrisville, Rhode Island,
and the EP A Records Center at 90 Canal Street in Boston, Massachusetts.
D.
Background on Community Involvement and
Concerns
Site History
The Western Sand & Gravel Site is located in the towns of Burrillville and North
Smithfield, Rhode Island. The area around the Site is primarily semi-rural residential.
The 2O-acre Site overlies the Slatersville Aquifer, a potential major drinking water
source for the State of Rhode Island.
The Site was an active sand and gravel quarry from 1953 until 1975. From
1975 to 1979, 12 acres at the north end of the Site were used for the disposal of liquid
chemical and septic wastes. Contents of tank trucks were emptied directly into 12
open lagoons and phs, none of which was lined to prevent materiais from escaping.
Over time the wastes penetrated into the soil and reached the.groundwater. A plume
of contaminated groundwater spread north and northwest towards wells supplying
drinking water to homes on nearby properties.
Chemical dumping on the Site stopped in 1979 following efforts by RIDEM to
close the Site for violations of state regulations. In 1980, EPA removed approximately
60,000 gallons of liquid wastes remaining in the lagoons. In 1981, EPA proposed the
WESTERN SAND & GRAVEL SUPERFUND SITE
-------
.
addition of the Western Sand & Gravel Site to the National Priorities Ust making it
. eligible to. receive federal Superfund monies for investigatJon. In 1982. RIOEM took the
lead responsibility for the Site investigations and began a groundwater recirculation
pro.gram In m-effort to control the spread of contaminants in the groundwater.
In 1984, EPA issued a ROO that required the installatJon of a permanent
alternate water supply to service approximately 56 parcels of land, and the installation
of water filters to provide protection for homes with contaminants identified in their
wells until the permanent alternate water supply is functional. Starting in August 1984,
Olin Hunt Specialty Products, Inc. (Hunt), a potentially responsible party (PRP),
installed water filters in private homes with contaminated wells and in homes with wells
that might become contaminated. EPA began COnstruction of the water supply in
1990.
After conducting additional studies, EPA issued a second ROO in 1985. This
ROO required the installation of an impermeable cap over the contaminated soils and
a study to evaluate groundwater contamination and determine alternatives for
groundwater cleanup. Construction of the cap was completed by Hunt in 1987.
Hunt submitted the Groundwater Aemediallnvestigation (RI) Aeport in June
1990 and the Groundwater FS Aeport in October 1990 to EPA and AIOEM. EPA and
AIOEM had comments on both of these reports. EPA prepared addenda to both
reports to address the comments developed by both EPA and AJOEM. The purpose
of EPA's addenda was to present the conclusions as determined by EPA based on
the data collected by Hunt.
History of Community Activity at the
Western Sand & Gravel Site
In the past, community interest and activity around the Site had been very
intense. In 1978, local citizens formed a group called Protect Our Water (POW) in
response to the potential hazards posed by the Western Sand & Gravel Site and the
other hazardous waste sites in the area. In 1979, the Town Councils of Burrillville and
North Smithfield held a joint meeting to discuss the problems caused by the Western
Sand & Gravel Site. In December 1982, the Western Sand & Gravel Hazardous Waste
Coordinating Committee was formed by the BurrilMlle Town Council at the suggestion
of AIDEM to facilitate communication between RIOEM and local government on
matters Involving the Site. The Committee included representatives of POW, the
BunilMDe Town Council, the BurrilMlle Conservation Commission, the BurrilMlle
Building Inspector, and the AIDEM Project Officer. The committee met on a quarterly
basis and the meetings were open to the public and attended by the press. EPA's
own public meetings on the proposed water supply in 1984 drew between 50 and 100
persons each. The 1985 public meetings on the capping proposal, however, drew
only 10 to 20 attendees. The Coordinating Committee was never officially disbanded,
but it has not been active for almost five years.
4
-------
Community Interests During the Groundwater FS
Community interest and awareness about the Westem Sand & Gravel Site has
been' reladve~ during the FS and public comment period compared to the activity
t~ took place during the initial Site investigations. Many residents contacted for
community interviews in the Summer of 1990, including those who had been very
involved in the earty stages of Site discovery and listing, were not aware that another
remedy (groundwater treatment) remained to be decided upon. One resident noted
that lack of opportunity for citizen participation had not been the problem; rather. a
high rate of tumover in the neighborhood had contributed to a lower level of interest in
the community. Community concerns expressed in public meeting procee~ings,
resident interviews. and contacts with public officials prior to the release of the
Proposed Plan for groundwater cleanup are listed below. .
1.
P."lng till Pu/aslci and Gig Roads. Some residents believe EPA should pave
Pulaski and Gig roads after constIUction of the water line.
2.
Respons/blliry for costs aI future connections to the water supply.
3.
Concerns regarding construction of the waterlIne. Concems included dust
during construction. the location of the main and hydrants. the locations of
household connections to the main, and the type of valves to be used.
4.
Safety of using private wells for non-drlnlclng water purposes.
5.
Potential Contamination of the New Water Supply Wells.
6.
Safety of eating fish caught In the Reservoir.
7.
Technic.ar Feasibility of Groundwater Cleanup.
8.
Diminished Property Values.
e.
Need for communIcation of all well test result. to resIdents.
10. DI.trlbution of MeetIng Summaries to those who could not attend.
11. &cesslve length ofUme between EPA communIcation. with residents.
ApproxImately 20 residents attended the public informational meeting held on
February 11, 1991 by EPA. The principal community concerns expressed at that
meeting are given below.
.
Potential ecologlca/.tress on TarIcJln Srook and the S/atersville
ReservoIr. Residents were unclear on the definition of .stresS- and
were concemed with the potential for additional off-site spread of the
contamination.
.
propo.ed groundwater monitoring program.. Residents wanted to
know If household well monitoring would continue and if new bedrock
monitoring would be performed.
WESTERN SAND & GRAVEL SUPERFUND SITE
-------
.
.
Criteria for Implementation of active groundwater treatment.
Residents were interested in monitoring EPA's future Site evaluations
and cleanup decisions.
- Rnanclng of the cleanup. Residents wanted to know which PRPs
would be approached regarding the cost of the cleanup.
..
.
Operation of the acce.. re.trlctlon.. Residents questioned whether
EPA would have to pay the potentially responsible parties for the right
to restrict groundwater access.
.
Safety of the new water supply. Residents were concerned over the
possibility of Site contamination reaching the new water supply.
ID. Summary of Comments Received During the
Public Comment Period and EPA Responses
This Responsiveness Summary addresses the comments received by EP A
during the public comment period (February 12 to March 13, 1991) concerning the
Groundwater FS, FS Addendum, EPA's Proposed Plan for groundwater cleanup and
other documents in the Administrative Record for the Western Sand & Gravel Site.
Four sets of written comments were received during the public comment period from
RIDEM, Hunt, the Nasonville Water District, and a resident of the area near the Site. A
local citizen and a representative of RIDEM submitted oral comments at the informal.
public hearing. A copy of the public hearing transcript is included as Attachment B to
this document.
Part I - Citizen Comments
The citizen who commented at the hearing also submitted her comments in
written form dated February 28, 1991. Comments from the Nasonville Water District
were submitted by their attorney in a letter dated March 11, 1991.
Comment 1: The resident stated that the preferred alternative is nOt a cleanup
because It does not physically and actively "clean" the groundwater. She also noted
that the last two major remedies at the Site, the cap and the permanent water supply,
were not cleanups for the same reason.
EPA Re.pon.e: The selected remedy Initially relies on natural attenuation to restore
the contaminated groundwater at the Site. However, if the groundwater is not restored
at the rate predicted by models or faster, then active restoration shall be utilized.
Natural attenuation has been occurring through out the history of the Site and has
. significantly reduced the levels of contamination. According to an analysis of the
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actual data collected to date, natural attenuation may restore the groundwater in a
time frame that is equivalent to that of active restoration. EPA must select remedies
that sr, ~otective of public health and the environment. In addition, Section 121 of
CERCLA requires EPA to select remedies that utilize treatment to the maximum extent
pradicable, 8f!d to restore the groundwater within a timeframe that is reasonable given
the particular circumstances at a site. All of the remedies selected for this Site by EP A
r8duced the risks to public health and the environment posed by the Site.
Furthermore, since natural attenuation may restore the groundwater in a time frame
that is equivalent to that of active restoration, and since EPA shall implement active
restoration if natural attenuation is not effective, EPA has selected a remedy that
utilizes treatment to the maximum extent practicable at the Site.
Comment 2: The resident contended that the owners of the w.estern Sand & Gravel
Site and another nearby Superfund Site would benefit from the preferred alternative
because they would be paid by EPA lor the acquisition of access restrictions on their
propel1y. She reconwnended that no access restrictions be implemented and that the
future buyers of any affected parcels shou1d bear the responsibility for protecting
themselves from any groundwater contamination on their property.
EPA Response: EPA considered a number of ways during the feasibility study (FS)
to restrict access to the contaminated groundwater which poses an unacceptable risk
to public health. Access can be restricted through deed restrictions, zoning
restrictions, well ~ advisories, restrictions on obtaining sewer disposal system
permits, or acquisition of property or groundwater rights. EP A utilized acquisition of
property in the FS for the purposes of estimating the cost of implementing access
restrictions. The actual mechanism to be utilized to restrict access shall be
determined after EP A conducts negotiations with the potentially responsible parties
(PRPs). However, EPA believes that some form of institutional controls are essential to
insure that there is no human exposure to unacceptable risk at the Site during
remediation.
Comment 3: The resident asked how the wastes under the existing on-site cap
would be attenuated If the impermeable cap prevents rainwater from reaching the
wastes.
\
EPA R..pon.e: Natural attenuation has been selected to restore the contaminated
groundwater not the contaminated soils. The Impermeable cap has minimized the
amount m rainwater that passes through the contaminated soils. Therefore, the
impermeable cap has reduced the source of contamination of the groundwater. Clean
groundwater from upgradient of the Site will pass under the contaminated soils and
the existing cap. The groundwater from upgradient of the Site dilutes the
contaminated groundwater downgradient from the Site and reduces the
concentrations Of contaminantS. Dilution is only one of the mechanisms that will
reduce the level m groundwater contamination under natural attenuation. Natural
chemical and biological processes will also reduce the level of contamination in the
groundwater. In summary, the cap minimizes the source of contamination and allows
WESTERN SAND & GRAVEL SUPERFUND SITE
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the natural chemical, biological and dilution processes to reduce any remaining
contamination in the groundwater.
.
Comment 4: -The resident urged EPA to begin active restoration of the groundwater
""mediately and dispense with any additional time consuming studies or reports.
EPA Response: EPA considered implementing active restoration immediately at the
Site. However, EPA selected natural attenuation to restore the contaminated
groundwater. As discussed in response to Comment 1 above, natural attenuation has
been occurring throughout the history of the Site and has significantly reduced the
levels of contamination. According to an analysis of the actual ~ata collected to date,
natural attenuation may restore the groundwater in a time frame that is equivalent to
that of active restoration. In addition, natural attenuation is protective of public health
and the environment easier to implement and cost effective. However, the remedy
provides that if the groundwater is not restored at the rate predicted by models or
faster, active restoration shall be implemented.
Comment S: The resident stated that active restoration would have been more
efficient if performed ten years ago as proposed by the State of Rhode Island. She
said that active restoration is more difficult and time consuming now because the
wastes have spread out over a larger area since the State first proposed the remedy.
She stated that if groundwater treatment had been started as planned, the
groundwater would be clean by now.
EPA Respon.e: The concentrations of contaminants have decreased significantly in
magnitude and extent since the early history of the Site. This decrease is in pan due
to natural attenuation. As indicated in Figure 6 in Appendix A of the ROD. the
concentrations of total volatile organic compounds (TVOCs) in the groundwater offsite
have been as high as 1000 parts per billion (ppb). During the remedial investigation
conducted in 1988 and 1989, the concentrations of TVOCs in the same area have
been reduced to 10 ppb as indicated in Figure 4 in Appendix A of the ROD.
Therefore, the contamination has not spread out as the commenter has suggested. In
fact the magnitude and extent of contamination has actually been reduced
significantly.
Based on the hydrogeologic models conducted during the FS, it is estimated that it
would take approximately 10 to 17 years to restore the groundwater from the currently
observed concentrations to drinking water standards, by active restoration. EP A did
not evaluate the time it would take to restore the groundwater based on the higher
concentrations observed in the early history of the Site. However, since the
C'JOCentrations of contaminants were significantly greater than those currently
Observed, EPA believes that It would have taken significantly greater than 10 years as
stated by the citizen.
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Comment 6: The Nasonville Water District noted that natural attenuation had not
been used before at other Superfund sites including W.R. Grace in Acton, MA and the
Valley .~~ce. area at the Groveland Mills Site in Groveland, MA.
EP~. Ife.pon.e: Although natural attenuation was not used as the principal remedy
at the two Superfund Sites noted by the commenter. natural attenuation has been
utilized at other Superfund Sites including the Yaworski Site in Connecticut and the
Winthrop Landfill Site in Maine. The National Contingency Plan (NCP) provides EP A
with the authority to select natural attenuation to restore contaminated groundwater if
the circumstances at the Site warrant such a remedy (See NCP at 55 Fed. Reg. 8846,
March 8. 1990). At the Western Sand and Gravel Site. natural attenuation has over
time significantly reduced the level of contamination. The groundwater plume has
reached its maximum extent and is Qecreasing. in magnitude and areal extent.
According to modeling, the groundwater shaD be restored to cleanup levels in
approximately 24 to 28 years which is a reasonable period of time giving the
circumstances at the Site. According to actual data, the groundwater may be restored
in a faster period of time of 8 to 18 years.
Comment 7: The Nasonville Water District endorsed Alternative 5 (active restoration
with discharge to both groundwater and surface water. groundwater monitoring and
access restrictions or an anlternate water supply) over EPA's preferred alternative for
groundwater cleanup because they believe that it assures the greatest safety to
residents in the affected area. They note that this recommendation arises from the
fact that their consultants did not have sufficient time, specifically 'several months', to
review the groundwater study reports and addenda for the Site.
EPA Response: Except for Alternative 1 (restoration by natural attenuation and
groundwater monitoring), the protectiveness of all the alternatives is dependent on the
effectiveness of institutional controls at preventing future exposure to the contaminated
groundwater. If the institutional controls are effective at preventing exposure, then all
the alternatives are equally protective of pubUc health. If the institutional controls are
not effective at preventing future exposure, then the selected remedy shall utilize
active restoration to restore the contaminated groundwater. Therefore, the selected
remedy is equally protective to Alternative 5, the alternative recommended by the
Nasonville Water District.
EPA announced the results of the remedial investigation (RJ) to the public in a fact
sheet In November 1990. At that time, the fact sheet was mailed to all persons on
EPA'. community relations mailing list including representatives from the Nasonville
Water District. The fact sheet also announced the availability of the Administrative
Record. Copies of the AI and FS Reports deYeloped by Hunt as well as EPA's
Addendum to the AI Report. were available in the Administrative Record for review at
that time. EPA released the Proposed Plan on February 4, 1991 and held a comment
period from February 12, 1991 through March 13, 1991. Therefore, the Nasonville
Water District and their consultant had four months to review the majority of the
Infonnation available on the Site.
WESTERN SAND & GRAVEL SUPERFUND SITE
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Comment B: The Nasonville Water District recommends that further studies be done
to -Verify, compliment or contradicr the groundwater investigations performed by EP A.
EP~ .Re8pon8t: Further investigations shall be conducted to characterize the extent
of contamination in the bedrock system as well as the impacts to the surface water
and sediments. Based on the results of these investigations, EPA shall determine if it
is necessary to modify the selected remedy to include active restoration and/or long-
term monitoring of the surface water and sediments. However, with the exception of
the information regarding the characterization of the bedrock, surface waters and
sediments, EPA is satisfied with the accuracy of reports concerning groundwater to
date and believes the information obtained to date is sufficient to select a groundwater
remedy at this Site.
Comment 9: The Nasonville Water District stated that the Record of Decision should
make clear the criteria to be used in determining whether or not active treatment will
be implemented.
EPA Response: In response to the comments from the Nasonville Water District and
RIDEM, EPA has cJarified the language and the criteria in the ROD which shall be
utilized to trigger aewe restoration should natural attenuation not restore the
. groundwater at the rate predicted by modeling or faster. Uke the approach outline in
the preferred altemative, the evaluation consists of comparing the actual data
collected during future groundwater monitoring to the data predicted by hydrogeologic
models. The evaluation shall be conducted on four indicator compounds:
tetrachloroethene, trichloroethene, vinyl chloride and benzene. A statistical
comparison of the actual data to the theoretical data shall be conducted using the
nonparametric distribution free signed rank test of Wilcoxon with a 95 percent
significance level as described in Noncarametric Statistical Methods (by Hollander and
Wolfe, published in 1973 by John Wiley, on pages 26-38). In summary, the rank test
determines whether the trend established by actual data falls below the trend
established by the theoretical data. If the trend for the actual data does not fall below
the trend lor the theoretical data as determined by the rank test, active restoration
shall be impJemented. All compounds must pass the rank test. If one compound fails
the rank test, then active restoration shall be implemented. An example of the test has
been provided in AppencflX D of the ROD using the data collected during the RI for
benzene. EPA believes that this approach eliminates any vagueness in the trigger for
active remediation as it relates to groundwater contamination.
In addition to requiring active restoration if natural attenuation is not restoring the
groundwater at a rate predicted by modeling or faster, there are three other scenarios
which trigger active restoratior.. First, t"e select&d remedy al$O requires active
restoration of the groundwater and/or long-term monitoring of the surface water and
sediments If necessary to protect Tarkiln Brook. Second, based on a review of the
new information collected to characterize bedrock impacts, active restoration and/or
long-term monitoring may be implemented If necessary lor the protection of public
health and the environment. Finally, if effective institutional controls cannot be
implemented, the selected remedy utilizes active restoration to restore the
groundwater.
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Part II - State Comments
.. -
RIDEM provided oral and written comments at the public hearing through
Warren Angell, Principal Engineer, Division of Air and Hazardous Materials. RIDEM
Jater submitted more detailed comments through a letter dated March 13, 1991 from
Thomas D. Getz, Chief, Division of Air and Hazardous Materials. RIDEM comments are
summarized below.
General Comments
Comment 1: RIDEM feels that EPA's refusal to extend the comment period under the
current circumstances is arbitrary, capricious and characterized by an abuse of
discretion. RIDEM stated that it was made aware of EPA's concerns by letter dated
February 28, 1991 and that EPArequired voluminous information to make an informed
d~ision concerning State ARARs. Finally, failure by EPA to grant the requested
extension may be interpreted as evidencing EPA's pre-judgement of this issue or
procedurally denying the State an opportunity to supplement the record with
information that substantiates the applicability of State ARARs.
EPA Response: Following issuance of its Proposed Plan, EPA offered a 3O-day
public comment period. That period ended on March 13, 1991. In a letter received by
EPA on March 11, 1991, the Rhode Island Department of Environmental Management
(AIDEM) requested a 60 day extension of that comment period. In a March 13, 1991
letter, EPA denied that request. In a March 13, 1991 response letter to EPA, RIDEM
maintained that EPA's refusal to extend the comment period was arbitrary and
capricious and an abuse of Agency discretion. EPA does not agree.
EPA and RIDEM have been in close contact during the development of the current
remedy for the Site. EPA met with RIDEM staff on December 5, 1990 to present EPA's
preferred alternative for the Site. RIDEM had no signifiCant comments during this
meeting. EPA sent RIDEM copies of the Draft FS Addendum, which described the
preferred alternative, on January 4, 1991, January 9, 1991 and January 22, 1991.
RIDEM did not submit any comments on these drafts. On January 31, 1991, RIDEM
first indicated to EPA that It believed that the Rhode Island Groundwater Protection Act
(GWPA) constituted an MAR mandating active restoration. At that time, EPA
requested that RIDEM provide the rationale for this position, in writing, as soon as
possible. Thereafter, the only information that EPA received from RIDEM regarding
this issue was a facsimile transmission of the GWP A Itself. This was received by EP A
on February 21, 1991. Thereafter, EPA requested a meeting with RIDEM to obtain
further clarification of the GWPA as,a pot&nt~,ARAR. At that meeting, held on
February 26, 1991, RIOEM again verbally explained to EPA that It believes that the
'policies stated in the GWPA constitute an ARAR. At the conclusion of that meeting,
EPA again requested that RIOEM document its position and provide examples of how
it has enforced the GWPA's policies.
Regarding requests for extensions to the public comment period,
WES 7"ERN SAND & GRAVEL SUPERFUND SITE
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the Preamble to the National Contingency Plan, at page 8770, states that "in order to
be time~, ~ request generally must be received within two (2) weeks after the initiation
of the comment period.' The final decision on granting an extension is within the
Age~'s discr~ion. In the present case, EPA made repeated efforts to obtain
inforination from RIDEM regarding its GWPA policies. However, it was not until March
11~ 1991, thirteen (13) days after the February 26, 1991 meeting between RIDEM and
EPA, that RIDEM requested the extension. RIDEM had an opportunity, as provided by
the NCP, to request an extension within two weeks after the initiation of the comment
period. Similarly, RIDEM could have made such a request shortly after its February
26, 1991 meeting with EPA. Considering that EPA has been in close communication
with RIDEM on the Proposed Plan since earty December and throughout the remedy
selection process, and considering that RIDEM's request was received two days
before the expiration of the comment period, EPA properly refused the request. EPA
notes, however, that on March 13, 1991, RIDEM did provide to EPA an extensive set of
comments to EPA's Proposed Plan as well as the Agency's RI and FS Addenda.
COtnllJelJt 2: RlOEM stated that the Groundwater At study of contamination in Tarkiln
Brook and the SlalersviUs Reselvoir was inadequate and that the findings of the study
regarding risks to the environment and public health were therefore inconclusive.
RIDEM requested that the PRPs conduct additional sampling that adheres to RIDEM
guidelines in the Brook and Reservoir prior to EPA's selection of a groundwater
cleanup remedy. RIDEM provided a sampling plan for the Brook and Reservoir, dated
January 15, 1991, in the Department's comments.
EPA Response: RIDEM had the opportunity to comment on the workplan for the RI
and did not submit comments on the approach for investigating the impacts to Tarkiln
Brook and the SJatersvilie Reservoir. Hunt has indicated a willingness to cooperate
with RIDEM to resolve the issues associated with the impacts to Tarkiln Brook and the
Reservoir. The selected remedy allows for additional activities to be conducted if EP A
determines that the remedy is not protective of public health and the environment.
Comment 3: RIDEM stated that the investigation of contamination in the bedrock
system was inconclusive and that additional studies are needed prior to the selection
(t a remedy.RIDEM stated Its belief that data from existing bedrock wells and the
geology of the Site indicate that the bedrock is fractured. RIDEM recommends that
the bedrock well installed in 1980 be resampled in future sampling and that, prior to
the installation d any new bedrock wells, a geophysical survey be completed to insure
proper placement d those wells.
EPA Re.pon..: EPA agrees with RIDEM that additional data is needed to
characterize the bedrock system. In a letter dated February 7, 1991, EPA requested
that Hunt conduct additional Investigations of the bedrock system. EPA disagrees that
selection d the remedy for the Site should be delayed pending receipt of this
information. The selected remedy in the ROD provides for additional activities such as
active restoration and/or long-term monitoring if necessary for the protection of public
health and the environment.
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\,
In response to resampling the 1980 bedrock well, EPA has reviewed th~ drillers logs
for all the wells drilled during the early history of the Site. The deepest well drilled in
1980 was 72 feet deep. In addition, there was a well drilled in March of 1981, labeled
GZ3-2 (also identified as B-1), that was screened aI a depth of 115 feet deep. Based
on a comparison to the driller's logs for the two bedrock wells installed during the RI,
EPA has conetuded that none of the wells drilled prior to 1981 were located in the
~petent zone of bedrock. According to the well driller's log for C-4B, the weathered
fracture zone aI this location extends from a depth of 65 feet to a depth of 100 feet.
The weD screen for this weD was located in the competent bedrock from a depth of
138 feet to a depth of 148 feet. According to the drillers log for I1-3B, the weathered
fractured zone aI this location extends from a depth of 73 feet to a depth of 110 feet.
The well screen for this well was located in the competent bedrock aI a depth of 124
feet to a depth of 134 feet. In both cases, the weathered fractured zone was about 35
feet in thickness. According to the drillers log for the GZ3-2 well, bedrock was first
encountered at a depth of 92.5 feet. Assuming that the depth of the fractured zone is
approximately the same, the well screen for the GZ3-2 well would have to be located
at a minimum depth of 127.5 feet deep to be in the competent zone of bedrock. As
stated above, the GZ3-2 well was screened at a depth of 115 feet. This zone of the
bedrock is the upper fractured zone of the bedrock system. Conclusions regarding
the extent of contamination in this portion of the bedrock are not in question. The
purpose of conducting additional investigations of the bedrock system is to
characterize the deep bedrock system, not the fractured bedrock zone. Therefore,
EP A does not agree thai the wells drilled prior to 1981 will provide any useful
information for characterizing the deep competent zone of the bedrock system.
"
EPA has considered the use of geophysics for locating fractures. Since geophysics is
not an exact science, EPA has determined that a more appropriate approach at the
Westem Sand & Gravel Site is to install three additional bedrock wells between the
Site and the residential neighborhood to the west of the Site. These wells shall be
sampled for VOCs on a quarterty basis for one year at a minimum. Sampling would
be carried out in discrete intervals of the borehole where fractures are encountered
and using methods capable of isolating the interval. This approach should prevent
artificially Induced vertical flow from the overburden aquifer. The number of samples
per borehole shall depend on the number of fractures encountered. An open
borehole method of COnstruction would be utilized with the use of sampling devices
capable of sampling discrete levels in the borehole. EPA has concluded that the
probability of finding a fracture using this approach is greater than using geophysics.
Comment 4: RIOEM questioned the accuracy of the groundwater model used by
Hunt to characterize the Site. Specifically, RIOEM questioned the number of layers
employed by the model, the piezometric contours USed, the hydraulic conductivities
employed, the discharge point employed, and the modeling of Tarkiln Brook. RIOEM
stated that, because many of RIOEM's previously expressed concerns over the validity
of the model have not been addressed, RIOEM questions the remediation scenarios
and times generated by the model and the use of linear regression graphs developed
by EPA. .
WESTERN SAND & GRAVEL SUPERFUND SfTE
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EPA Re.ponse: EPA believes that the model provides a conservative-estimate of the
. time necessary to restore the groundwater to cleanup levels. The hydraulic
conductivity input into the model was 30 feet per day. The average hydraulic
conductivity observed during the RI was 70 feet per day. Therefore, Hunt utilized a
conservadve hydraulic conductivity as input to the model This approach results in
CQnservatJve predictions of the restoration time frames. In other words, since Hunt
utilized a conservative value for the hydraulic conductivity, the time for restoration
predicted by the model may be greater than the actual time for restoration. This
conclusion is also supported by the actual data collected to date. Based on EPA's
review of the actual data collected, the groundwater may be restored in 8 to 18 years
as opposed to the 24 to 28 years predicted by the model
Use of a multilayer model would have been more representative of the actual
conditions at the Site. Adding layers to the model would result i.n restoration time
frames which are less than those currently predicted. However, the ratio between the
time frames for natural attenuation and active restoration would have remained the
same. In addition. EPA concluded that sufficient data does not exist to calibrate a
multi-layer model Therefore, EP A determined that a single layer model provides the
best conservative estimate of the restoration time frame.
The model utilizes Tari
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Rhode Island Department of Environmental Management's (RIDEM) Groundwater
Section to Tom Gatt. Chief of RIDEM's Division of Air and Hazardous Materials.
,- --
The~ater Protection Act, at 546-13.1-2, states, in relevant part, that 8(t]he
general assemI;)Iy hereby declares and recogniZes that: on
(3) It Is the paramount policy of the state to protect the purity of present and
future drinking water supplies by protecting aquifers, recharge areas. and watersheds;
(4) It Is the policy of the state to restore and maintain the quality of groundwater
to a quality consistent with its use for drinking supplies and other designated
beneficial uses without treatment as feasible. All groundwaters of the state shall be
restored to the extent practicable to a quality cOnsistent with this policy;
(5) It Is the policy of the state not to permit the introduction of pollutants into the
groundwaters of the state in concentrations that are known to be toxic. carcinogenic,
mutagenic, or teratogenic. To the maximum extent practical. efforts shall be made to
require the removal of those pollutants from discharges where such discharges are
shown to have already occurred;
(6) Existing and potential sources of groundwater shall be maintained and
protected. Where existing quality is inadequate to support certain uses, the quality
shall be upgraded if feasible to protect the present and potential uses of the resource;
RIDEM maintains that it has consistently implemented the above mentioned policies to
require active remediation when an aquifer is degraded below its intended use. The
groundwater beneath the WS&G Site is primarily classified GAA-NA, meaning that
while GAA groundwater is normally suitable for public drinking water use without
treatment, the groundwater at the Site is not attaining that goal. According to RIDEM's
interpretation of the above policies, active remediation is required to restore the
groundwater at the Site to GAA. RIDEM further contends that this interpretation of its
policies should be an applicable or relevant and appropriate requirement (ARAR) that
EPA. applies when choosing a remedy for the Site.
EPA Respon,.: EPA does not believe that the policies articulated under the
Groundwater Protection Aet are an ARAR. In order for a state requirement to be an
ARAR. It must be promulgated. Section 300.400 (g)(4) of the National Contingency
Plan (NCp) states that -the term 8promulgatgd8 shall mean that the standards are of
general applicability and are legally enforceable.8 The State's policy of active
remediation Is not legally enforceable.
EPA defines as legally enforceable requirements those State regulations or statutes
that contain specific enforcement provisions or are enforceable by means of the
general authority in other laws or in the State constitution. CERCLA Compliance With
Other Laws Manual, Part II, OSWER. August. 1989.
The goals set forth in the Groundwater Protection Ad are not themselves enforceable.
The Preamble to S 300.400 (g)(4) of the NCP states that 8(g]eneral goals that merely
express legislative intent about desired outcomes or conditions are not ARARs.8 The
WESTERN SAND & GRAVEL SUPERFUND Snc
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relevant words of the statute are specifically phrased as policy objectives. At chapter
46-13..1-4,- the GWPA mandates that "[tJhe Director shall promulgate rules setting forth
the range of responses that he or she may take" to maintain the integrity of the various
ctasses of ~er. If such rules had been promulgated and such rules had
reqUired treatment of class GAA-NA groundwater to established drinking water
s1andards. then such rules would have been ARARs. They would have been ARARs
because they would have been promulgated and enforceable standards. Although by
statute such rules were to have been promulgated by February 28, 1989, to date the
State has not promulgated such rules. Thus. there is currently no promulgated rule
that clarifies the policies set forth above. It is unclear what factors the State uses to
determine what is a "practical" versus a 'practicable" effort to restore a site. Similarly,
no dear definition of "restore" is provided. It is not sufficient that the State claims to
consistently interpret the policy statements as requiring active remediation. There
must be a promulgated rule describing the State's preference for active remediation in
order to enforce this policy as an ARAR. No such promulgated rule exists.
EPA does not dispute that the director of RIDEM obtains authority from R.I. Gen. Laws
chaptefs 42-17.1 and 45-12. These chapters give the director the general authority to,
among other things, protect the state's natural resources and enforce all promulgated
rules and regulations. However, for the reasons discussed above, EPA does not
believe that RIDEM's policy of preference for active restoration is a standard that
RIDEM can enforce.
As a non-enforceable policy, EPA recognizes that RIDEM's preference for active
remediation has been applied in numerous actions between the State and private
parties. As it is an effort to consistently apply the policies stated in the GWP A, EP A
recognizes this preference for active remediation as a t~be-considered (TBC)
standard. While not a potential ARAR, EPA has considered the State's policy during
the formulation of the current remedy.
Comment 6: RIDEM stated that the Record of Decision should make clear the
criteria to be used in determining whether or not active treatment will be implemented.
RIDEM noted that the criteria should cover both surface water and groundwater
conditions.
EPA R..pon.e: In response to the comments raised by RID EM and the Nasonville
Water District on the criteria to be used in determining whether or not active
restoration shall be Implemented, EPA modified the approach to conducting the
evaluation of natural attenuation. Uke the approach outlined In the preferred
alternative, the evaluation consists of comparing the actual data collected during future
groundwater monitoring to the data predicted by hydrogeologic models. The
evaluation shaD be conducted on four indicator compounds. A statistical comparison
of the actual data to the theoretical data shall be conducted using the nonparametric
distribution free signed rank test of Wilcoxon with a 95 percent significance as
described In NonDarametric Statistical Methods (by Hollander and Wolfe, published in
1973 by John Wiley, on pages 26-38). In summary, the rank test determines whether
. the trend established by actual data falls below the trend established by the
theoretical data If the trend for the actual data does not fall below the trend for the
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theoretical data as determined by the rank test, active restoration shall be
. imple~~ed. All compounds must pass the rank test. If one compound fails the rank
test. then active restoration shall be implemented. An example of the test has been
prcMded In Appendix D d the ROD using the data collected during the AI for
~nzene. EPA believes that this approach eliminates any vagueness in the trigger for
active remediation as It relates to groundwater contamination.
In addition to requiring active restoration I natural attenuation is not restoring the
groundwater at a rate predicted by modeling or faster, there are three other scenarios
which trigger active restoration. First. the selected remedy alsO requires active
restoration of the groundwater and/or Iong-tenn monitoring d the surface water and
sediments if necessary to protect Tarkiln Brook. EPA could not develop specific
triggers for the results of the surface water and sediment investigation since it is not
known, at this point, exactly what type of data shall be collected. Second. based on a
review of the new information collected to characterize bedrock impacts, active
restoration and/or long-term monitoring may be implemented if necessary for the
protection of public health and the environment. Finally, if effective institutional
controls cannot be implemented. the selected remedy utilizes active restoration to
restore the groundwater.
Comment 7: RIDEM expressed concern that the proposed temporary access
restrictions may. not effectively prevent human exposure to the contaminated
groundwater in all potential development scenarios. RIDEM did not provide any
examples or elaboration on this comment. RIDEM cited this concern as a JUStification
for immediately employing active treatment of the groundwater.
EPA Response: EPA agrees with RIDEM that the effectiveness of institutional
controls, Including access restrictions, is difficult to predict. Therefore, the selected
remedy requires active restoration of the groundwater if effective institutional controls
cannot be implemented. However, EPA does believe that institutional controls. if
effectively implemented, will adequately prevent human exposure to contaminated
groundwater during the remediation.
Comment 8: RIDEM noted that remedial activities carried out to date have not
addressed detection or loCatIon d non-aqueous phase liquids (NAPLs). The nature of
the wastes at the Site and observations made during monitoring weD sampling
suggest the presence of NAPLs. RIDEM recommended that future sampling address
this Issue.
EPA Response: The concentration of contaminants at the Site are not indicative of
the presence of NAPLs. Groundwater concentrationS of 5 to 10 percent of the field
solubility of a compound is thought to suggest the presence of NAPLs. The
concentrationS d contaminants at the Site currently do not approach this level.
However. In response to RIDEM's concern. the selected remedy includes the use of an
interface probe to identify the presence d NAPLs. This test shall be conducted during
the first round of groundwater sampling and shall confirm the conclusion.
WESTERN SAND & GRAVEL SUPERFUND SITE
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Comment 9: RIO EM stated that historic data indicates that the "F" weJl area may be
contaminated, but that this area has not been investigated by EPA RIOEM
rBCOIY!mends that this area be investigated for contamination as part of future
sampling - programs.
EPA R..ponn: According to Appendix C of the RI Report (June, 1990), the"F" well
area is located south of the existing cap, at the fork in the access road to the Site. As
presented in Table T.8 in Appendix T of the RI Report, this well was sampled on
November 29, 1979 and found to contain the following contaminants:
Contaminants
1,1,1-Trichloroethane
Trichloroethene
Toluene
Cadmium
Copper
Lead
Zinc
Concentration
3 ppb
2 ppb
91 ppb
2 ppb
70 ppb
5 ppb
85000 ppb
MClJMCLG
200 ppb
5 ppb
1000
5ppb .
1300 ppb*
5 ppb
5000 ppb
* Proposed MCL
With the exception of zinc, all of these compounds were detected at or below the MCL
or MCLG. Installation of the impermeable cap has resulted in significant decreases in
the magnitude and extent of contamination. Therefore, it is not expected that
contamination is currently present in this area at levels that present a risk to public
health. This conclusion is also supported by the fact that contamination was not
detected in the C-1 well which is located immediately to the east of the F well location.
In addition, the concentrations of zinc currently detected in the groundwater
downgradient from the Site do not approach the concentration detected at this well in
1979. The average and maximum concentration of zinc detected during the current RI
were 25 ppb and 269 ppb, respectively. In conclusion, future investigations of
contamination in this area are not justified and will not be included in the selected
remedy.
Comment 10: RIOEM stated that it had found "discrepancies" in cost estimates for
remedial alternatives in the Groundwater FS and that the estimates may be higher
than necessary. RIDEM recommends that EPA review the cost estimates and, if
necessary, meet with the PRPs conceming the cost estimates.
EPA R..pon.e: EPA conducted a thorough review of the cost estimates in the FS
Report. In fact. EPA requested that Hunt recalculate some of the costs. The revised
cost estimates were presented in a letter from Robert McCaleb to Lynne Fratus dated
January 22, 1991. A copy of the revised cost estimates were placed in the
Admnistrative Record. In addition, Hunt fOlWarded a co~ of the estimates to RIOEM.
. ACcOrding to EPA's Guidance for Conductina Remediallnvestiaations and Feasibility
Studies under CERCLA (EPA/540/G-89/004), the costs developed during the FS are
prepared with an accuracy of +50 percent to -30 percent O.e. actual costs may be 50
percent greater or 30 percent less than the estimate). The costs are intended to be
estimates for the sake of relative comparison. EPA has concluded that the costs in
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the FS Report are within this level of accuracy and were appropriate for the
comparison of alternatives.
Comment f f: RIDEM asked for responSes to all previous RIDEM comments not yet
Jlddressed by EPA on the Groundwater RI, Groundwater FS, and Addenda.
EPA Respon.e: RIDEM's comments on the Groundwater RI Addendum and FS
Repon Addendum were indicated in an attachment to AlDEM's Jetter dated March 13,
1991 to EPA. EPA's responses to these comments are presented below. RIDEM's
outstanding comments on the RI Repon were indicated in a previous letter dated July
24, 1990 from RIDEM. A copy of this Jetter was also enclosed with RIDEM's letter
dated March 13, 1991. Respo~ses to these comments are aIso.provided below.
Since RIDEM has not identified outstanding comments on the FS Repon separately,
EPA has assumed that these comments were included in the attachments discussed
above.
Comments on Groundwater RI Report Addendum
Comment 12: RIDEM noted that the repon should indicate that tests of NAPLs were
not carried out at the Site. The repon should note why these tests were not carried
out.
EPA Respon.e: As discussed in response to Comment 8 above, the concentration
of contaminants at the Site are not indicative of the presence of NAPLs. Groundwater
concentrations of 5 to 10 percent of the field solubility of a compound is thought to
suggest the presence of NAPLs. The concentrations of COntaminants at the Site
currently do not approach this level. However, in response to RIDEM's concern, the
selected remedy includes the use of an interface probe to identify the presence of
NAPLs. This test shall be conducted during the first round of groundwater sampling
and shall confirm the conclusion.
Comment 13: RIDEM recommended that the Groundwater RI Addendum state that
the piezometric contours for sections of the aquifer east of the Site are extrapolated
contours. AlDEM requested a description of the assumptions used to generate these
contours. .
EPA Re.pon.e: Both EPA and Camp Dresser and McKee, Inc., EPA's technical
support contractor, reviewed the piezometric contour maps presented in the RI Repon
for those portions 01 the Site which were contaminated. With the exception of the
. pi~c:.m~ric maps for the deep portion of the aquifer, EPA has concluded that the
maps presented in the AI Repon accurately represent the hydrogeologic conditions of
the overburden aquifer. EPA Included a corrected piezometric map for the deep
portion of the overburden aquifer In the RI Report Addendum. Based on the results
from the wells labeled 1-7 and 1-4, which are located to the east of the plume, elevated
- levels of contamination have not been detected to the east of the Site. Therefore, EP A
concluded that piezometric data in this area, which was demonstrated to not be
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contaminated. was not necessary. Regarding RIDEM's request for the assumptions
that were utilized to generate the piezometric maps. piezometric maps are developed
by cOfV1~ing points with equal piezometric measurements as is standard procedure
in the field of hydrogeology.
Oomment 14: R/DEM requested that EPA describe the off-site source of
contamination found in residential wells outside of the historical maximum extent of
contamination described in Fig. 5.8 of the Groundwater RI Addendum, and that EPA
explain the methods used to confirm this source.
EPA Response: The purpose of the RI was to characterize the extent of
contamination from the Site not from other sources beyond the .Slte. The extent of
contamination in the overburden aquifer has been well defined by the data collected
during the R/. However. further data must be collected to charaCterize the extent of
contamination in the bedrock system. Depending on the construction technique used
to install the residential wells. contamination from the bedrock system could be one
source of contamination in the residential wells.
Comment 15: RIDEM stated tMt the Groundwater RI Addendum should indicate the
total number of sampnng rounds performed tor VOCs. SVOCs and metals. RIDEM
also recommended that the report comment on the adequacy of the number of
sampling rounds for characterization of the overburden contamination.
EPA Response: The RI Report Addendum developed by EPA was intended to
supplement the RI Report developed by Hunt. The number of sampling rounds for
VOCs. SVOCs and metals is identified in the RI Report. The RI Report Addendum
explicitly directs the reader to refer to the RI Report for additional information on the
Site and the investigations. The following sampling rounds for groundwater were
conducted during the RI from May 1988 through February 1989: four rounds for VOCs,
two rounds for SVOCs and one round for metals. In addition, three additional
sampling rounds for VOCs were conducted between September 1989 and November
1990. EP A has concluded that the amount of data collected is sufficient for
characterizing the current extent of contamination in the overburden aquifer.
Comment 16: RIO EM requested that the RI Report Addendum should indicate the
possible mechanisms to be used to determine if the bedrock wells are contaminated.
EPA Response: In a letter dated February 7, 1991, which was included in the
Administrative Record, EPA requested that Hunt conduct additional activities to
characterize the extent of contamination in the bedrock system. As a first phase, EP A
requested that Hunt inStall three additio/1a1" bedrc.ck wells between the Site and the
" residential neighborhOOd to the west of the Site. These wells shall be sampled for
VOCs on a quarterty basis for one year at a minimum. Sampling would be carried out
in discrete Intervals of the borehole where fractures are encountered and using
methods capable of isolating the interval. This approach should prevent artificially
induced vertical flow from the overburden aquifer. The number of samples per
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borehole shall depend on the number of fractures encountered. An open borehole
method of construction would be utilized with the use of sampling devices capable of
samP.'ing discrete levels in the borehole.
Comment 1.7: RIOEM Stated that the RI Report Addendum should note the results of
Jhe surface water and sediment sampling of Tarkiln Brook and Slatersville Reservoir.
The Report should indicate the number of sampling rounds and the last sampling date
for the Tarkiln Brook and the SJatersville Reservoir.
EPA Re.pon.e: As disc1lSsed in response to Comment 15, the RI Report Addendum
developed by EPA was intended to supplement the RI Report developed by Hunt.
The results of the surface water and sediment sampling, the number of sampling
rounds and the date of the sampling rounds are identified in th$ RI Report. The RI
Report Addendum explicitly directs the reader to refer to the RI Report for additional
information on the ,site and the investigations. Tables 5 and 6 in Appendix B of the
ROD summarize the results of the surface water and sediment investigations
conducted dumg the RI. Two rounds of sampling were conducted for the surface
water and sediments in September 1988 and August 1989. The last sampling round
for Tarkiln Brook was conducted in August 1989. The last sampling round in the
Slatersville Reservoir was conducted in September 1988.
Comments on Groundwater FS Report Addendum
Comment 18: RIOEM questioned the validity of the groundwater model based on
RIOEM's belief that the model assumes groundwater from the Site discharges into
Tarkiln Brook even though evidence from the Groundwater RI indicates that some
groundwater flow from the Site passes under the Brook. RIOEM requested a
determination of which groundwater flow path is correct and an assessment of any
Impact this situatJon could have on the cleanup times predicted by the model. RIOEM
expressed its lack of confidence in the model's predictions for cleanup times and
recommended use of an altemate method of assessing the remedial alternatives.
EPA Re.pon.e: As d'1SCUSSed in the response to Comment 4, the model utilizes
Tarkiln Brook as a discharge point for contaminated groundwater. EPA recognizes
that there Is a component of flow which passes under the Brook. However, EP A has
conctuded that this component of flow is a small component relative to the amount of
water discharging into the Brook. This conclusion is based on a review of the actual
concentrations observed beyond the Brook. The concentrations beyond the Brook
currently meet Federal and State Orinking Water Standards. Therefore, the time for
restoration 10 cleanup standards is negligible a.1d shall not impact the overall time for
groundwater restoration at the Site. The rOOdels utilized in the FS Report are
. demonstrated and well known in the field of hydrogeology and are recommended for
use In EPA's guidance documents.
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Comment 19: RIDEM noted a discrepancy between the restoration time for Scenario
2 In the Groundwater FS and the restoration time for Scenario 2 in the FS Addendum.
RID EM recommended that the FS Addendum show the same time estimate as the
Groundwater FS.
PA Re.pon.e: EPA reviewed the restoration time frames presented in the FS
Report and found them to be incorrect. EPA requested that Hunt revise the
restoration time frames. The revised restoration time frames were presented in
correspondences from Robert McCaleb to Lynne Fratus dated December 14, 1990 and
January 7, 1991. A copy of the revised restoration time frames were placed in the
Administrative Record. In addition, Hunt forwarded a copy of the revised restoration
time frames to RIDEM. In summary, the restoration time frames presented in the FS
Report Addendum are based on the revised estimates and are correct.
Comment 20: RIDEM stated that for completeness, a table of toxicity, persistence,
magnitude, and frequency of detection data for all contaminants at the Site as well as
details of the formula used for the selection of indicator compounds should be
included in the FS Addendum.
EPA Response: Information pertaining to the toxicity, persistence, magnitude and
frequency of detection were summarized in Sections 5 and 6 of the RI Report. Some
of these tables are also presented in Appendix B to the ROD. .
Comment 21: RIDEM requested justification for EPA's proposed use of only four
indicator compounds to evaluate the effectiveness of natural attenuation. RIDEM
requested that EPA make a finding regarding the adequacy of using only four
indicator compounds for making public health and environmental decisions. RIDEM
requested details on what action EP A would take if increases are observed in the
levels of compounds not among the four chosen indicators. RIDEM stated that, if
effectiveness decisions are to be based on monitoring of other contaminants, EP A
should describe the decision mechanisms for these other compounds.
EPA Response: The monitoring program identified in the selected remedy requires
periodic monitoring of a number of contaminants. However, EPA selected four
indicator compounds, tetrachloroethene, vinyl chloride, benzene and trichloroethene,
to evaluate the effectiveness of natural attenuation. Specifically, EPA shall conduct a
statistical analysis on the performance of each of these four compounds. Conducting
such an evaluation on every compound detected would not be cost effective. The use
of indicator compounds is commonly used in the Superfund process, particularly in
conducting Risk Assessments, and is discussed in such guidance documents such as
the Guidance for Conductina Remediallnvestiaations and Feasibility Studies Under
CERCLA (EPA/540/G-89/004) and Suoerfund Public Health Evaluation Manual
(EPA/540/1-86/060).
The VOCs are the most frequently detected compounds at the Site. Furthermore, the
VOCs result in the greatest risk to public health. Therefore, EPA selected four VOCs
as indicator compounds. Trichloroethene was the most frequently detected
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compound. Tetrachloroethene was also frequently detected and is on~ of the most
. persistent compounds detected at the Site. Vinyl chloride was the compound which
presents the greatest risk to public health. Finally, benzene was selected as
representative of an average for all the compounds detected with respect to all the
crtt8fia. The performance of each of these compounds shall be evaluated during
future evaluatienS ~ natural attenuation. If any one of these compounds is found not
tQ be decreasing at the rates predicted by modeling or faster, then active restoration
shall be implemented. The monitoring results for the other compounds shall also be
reviewed by EPA. EPA SUSpects that these compounds shall behave in a similar
fashion to the indicator compounds selected. If EPA determines that the results do
not support EPA's conclusions, EPA shall modify the ROD to Insure that the remedy is
protective of public health and the environment.
Comment 22: RIDEM requested justification for EPA's choice of monitoring wells to
provide the data for judging the effectiveness of natural attenuation. RIDEM asked
whether the moveme~ of slugs of contaminants from the Site is expected and whether
the crileria for judging the effectiveness of natural attenuation will address slug
movement. RJOEM noted that the groundwater model did not consider slug
movement.
EPA Response: The Proposed Plan requires that data from well clusters C-2, C-3. C-
4, C-s, C-6, 1-2 and 1-3 be utilized in the evaluation of natural attenuation. The
Proposed Plan further states that these well clusters are the seven most contaminated
well clusters. In response to comments received from RlDEM and Hunt, EPA once
again reviewed the results from the RI and modified the selection of well clusters. The
nature of contamination detected in 11-3 was similar to the nature of contamination in
C-S. Therefore. the 11-3 well cluster was added to the list of well clusters to be utilized
in the evaluation of natural attenuation in the selected remedy. Similarly, the nature of
contamination in 1-6 was similar to that in 1-2. Therefore, the 1-6 well cluster was also
added to the evaluation. The remaining wells at the Site were either not contaminated
or contained compounds which did not exceed ARARs. If RIDEM did not agree with
the selection of wells, RlDEM should have recommended additional wells for EPA to
consider during the comment period.
Since the source of contamination has been minimized, EPA does not believe that a
slug of contamination shall emerge from the Site in the future. However, the
monitoring program would detect such an occurrence. Furthermore, such an
occurrence would likely trigger active restoration. Groundwater flows at a rate of 250
feet per Y"- The distance from the cap to the Brook is approximately 185 feet.
Therefore. if a slug were to emerge, increased concentrations of contaminants would
be noted for a period of at least one year. Due to the sensitivity of the rank test (95
percent significance), this type of deviation in the data would most likely trigger active
restoration.
Comment 23: RIDEM requested a detailed outline and justification of the decision
process EPA would use to determine whether or not to implement active treatment.
RIDEM specifically asked whether active treatment would be implemented if only one
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contaminant were found in excess of the concentrations predicted by ttie groundwater
model RlDEM also asked if comprehensive public health risk analyses would be
petforrnect on the data collected during the monitoring of the cfeanup and if these
wou~ be used In the decision process.
ERA R..pon.e: As diSCIlSsed in response to Comment 6, EPA modified the
approach to conducting the evaluation of natural attenuation. The modified approach
is described in more detail in EPA's response to Comment 6. Furthermore, as
discussed in response to Comment 21 above, if one of the four indicator compounds
fails the rank test, active restoration will be implemented. Finally, a risk assessment
shall not be conducted as part of each evaluation. However, at the time when interim
cleanup levels have been achieved, EPA shall conduct a risk assessment on the
residual groundwater contamination. This risk assessment shall assess the cumulative
risks for carcinogens and noncarcinogens posed by consumption of site groundwater.
If the risks are not within EPA's risk management goal for carcinogens and
noncarcinogens thr . the remedial action will continue until protective levels are
attained or the remedy Is otherwise deemed protective.
Comment 24: RIDEM asked for an assessment of EPA's confidence in the
predictions of the groundwater model for the active treatment scenario and in the
location of extraction wells for active treatment given that the model used by EP A does
not allow for the optimization of extraction well location and number. Based on this
limitation in the model, RIDEM questioned the remediation scenarios and times
generated by the model. RIDEM requested a description of mechanisms that could be
used to refine the placement of extraction wells for active treatment.
EPA Re.ponse: As stated in response to Comment 4, EPA believes that the model
provides a conservative estimate of the time necessary to restore the groundwater to
cleanup levels. The purpose of the model is not to identify the final locations and
pumping rates for the extraction wells but to estimate the restoration time frame.
During the calibration of the model, Hunt evaluated different pumping rates. For
example,l;iu"1t attempted to capture the 1 ppb plume at a total pumping rate of 145
gpm. However, under this scenario, several of the cells went dry. Therefore, Hunt
reduced the total pumping rate to 132.5 gpm. This scenario did not result in drying
out the cells. Based 00 EPA's review of the assumptions utilized in the model, EPA
has concluded that the results of the model are an accurate estimate of the restoration
time frame. However. If active restoration Is implemented, a pump test would be
conducted during design to optimize the number, the location and pumping rate for
the extraction wells.
Comment 25: RIDEM requested justification for the distribution of wells, the
frequency of sampling and the selected list of contaminants specified in EPA's
proposed groundwater monitoring plan. RID EM specifically asked why heavy metals
and semi-volatile organic compounds were not incfuded in the groundwater monitoring
even though they were included in the proposed surface water monitoring plan.
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EPA Response: EPA evaluated the groundwater monitoring plan for the overburden
aquifer In the FS Addendum and the Proposed Plan and has modified the monitoring
plan ~ on comments received from RIOEM and Hunt. The modified overburden
g~ater monitoring program is as follows:
.
.- The following twenty eight (28) wells shall be monitored on a quarterly
basis for volatile organic compounds (VOCs) and on an annual basis
for semi-volatile compounds (SVOCs) and metals.
C-1 Co3$ C-SS 1-2$ 1-65
C-2$ C-3M C-5M I-2M 1-6M
C-2M C-30 C-SD 1-20 1-60
C-20 Co4$ . C-6S 103$ 1103$
C4M C-6M I-3M I1-3M
C40 C-60 I~O I1-3D
A review of the analytical data presented in the RI Report indicates
that, with the exception of C-1 which is upgradient of the Site, these
wells were the most contaminated wells in the plume (See Figure 4.2
in RI Report, Hunt, June 1990). All of these wells shall be utilized to
evaJuaie the effectiveness of natural attenuation. Quarterly monitoring
is needed to provide enough data to statistically evaluate the
effectiveness of natural attenuation. In addition, it is anticipated that
the probability of implementing active restoration is the greatest in the
first six (6) years. Therefore, quarterty monitoring must be conducted
for a minimum of six (6) years.
VOCs are the most prevalent compounds detected at the Site.
However, some SVOCs and metals have also been detected in the
groundwater. Based on EPA's review of the data. these compounds
are not expected to increase in magnitude and extent. However, due
to concerns raised by RIDEM on the impacts to Tarkiln Brook and in
order to verify this conclusion, annual monitoring of SVOCs and metals
has also been included in the monitoring plan. After a minimum of
three years of monitoring, the monitoring plan may be modified to
reduce the frequency of sampling if approved by EP A
.
In addition, the following twenty eight (28) wells shall be monitored on
an semi-annual basis for VOCs.
1-1S I-SS l-as 1104$ 11-6S
I-1M 1-5M I-aM 114M 11-6M
1-10 I-50 1-80 1140 11-60
I-4S 1-75 11-2$ II-SS
14M 1-7M II-2M 11-5M
140 1-70 11-20 II-50
These wells were found to be in the overburden plume or just outside
of the plume during the RI. As stated above, EPA has concluded that
the magnitude and extent of contamination in the overburden aquifer
is decreasing. In addition, EPA has concluded that there is a small
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.-
component of flow which passes under Tarkiln Brook and discharges
. into the Slatersville Reservoir. This conclusion is based on seven
- . sampling episodes over a two and a half year period. However, due
to concerns raised by RJDEM on the potential impacts to the Reservoir,
- this conclusion shall be verified with additional long-term data. After a
minimum of three years of monitoring, the monitoring plan may be
modified to reduce the frequency of sampling if approved by EP A
Comment 26: RID EM stated that the FS Report Addendum should note why welll!-
3B was not included in the criteria wells. The Report should also note whether
additional bedrock wells will be included in the criteria well set. The EPA should
outline the action to be taken if contamination is found In these wells.
EPA Response: As stated in the RI Report Addendum, there are two explanations for
the contamination found in the bedrock wells. One explanation is that the
groundwater migrated under natural conditions and contaminated the wells. The other
explanation is that the contamination resulted from artificially induced vertical
migration. The RI Report Addendum further states that additional data is needed to
verify the conclusions regarding ;.~e bedrock system. The ROD states that additional
investigations to characterize the extent of contamination in the bedrock shall be
conducted. Based on the results of the investigations, EPA will determine if it is
necessary to modify the selected remedy to include active restoration and/or long-term
monitoring of the bedrock system. In summary, since the source of the contamination
in the I1-3B well has not yet been determined, it is not appropriate to include this well
in the set of wells to be utilized to evaluate the effectiveness of natural attenuation.
Comment 27: RIDEM stated that the FS Addendum should designate the future
upgradient sediment and surface water sample locations and justify the locations.
Furthermore, RIDEM requested that EPA review a memo which outlines the
Investigations of Tarkiln Brook. .
EPA Response: Since the scope of the surface water and sediment investigations
had not been finalized, the details of this investigation were not included in the Final
FS Report Addendum or the Proposed Plan. Furthermore, since collection of this data
is not part of the selected remedy, the details of the surface water and sediment
investigation have not been specified in the ROD. EPA expectS that RIDEM shall
specify the scope of these investigations. The selected remedy states that after
reviewing the results of the investigation, EPA will determine if it is necessary to modify
the selected remedy to include active restoration of the groundwater and/or long-term
monitoring of the surface water and sediments.
Comment 28: RIDEM requested a clarification of what model EPA used to produce
the graphs of theoretical concentrations In Section 2 of the FS Addendum. RIDEM
asked whether a model used by EPA was employed to validate the model used by
H&n in the Groundwater FS, and, if so, whether the models concurred. RIDEM
specifically requested documentation of concurrence. RIDEM also requested details of
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the groundwater model used by EPA as described in Section 2 of the FS Addendum.
RlOE~ requested an assessment of EPA confidence in EPA's model for determining
the need for active treatment.
,
...
EPA R.spotiie: A combination of three models were utilized to determine the time
frames for restoring the groundwater at the Site. MOOFLOWand STUNE were utilized
to determine the time necessary to achieve one flush of the aquifer. In addition, the
EPA Batch Flushing Model was utilized to determine the number of flushes necessary
to reduce the concentration of a particular contaminant to its cleanup level. Hunt
combined the results of these models to develop the restoration time frames in the FS
Report.
EPA reviewed the input and output from MOOFLOW and STUNE and determined that
these models provided an accurate representation of the time it takes to conduCt one
flush of the aquifer. EPA staff also ran the EPA Batch Flushing Model and verified
Hunt's results to this model. In addition, EP A utilized the output from the Batch
Flushing Model to develop the compliance curves placed in the FS Report Addendum
and Proposed Plan. The inputs and outputs to this model were previously offered to
RIOEM for review. Copies of this information have been placed in the Administrative
Record. In summary, EPA has concluded that the models utilized by Hunt provide an
accurate estimation of the time to restore the groundwater by natural attenuation.
Therefore, EP A has utilized the results of these models to generate the theoretical
predictions of the contaminant concentrations in the future. If future trends
determined by the actual data are not equal to or less than the trend determined by
. the theoretical predictions, then active restoration shall be utilized.
Comment 29: RIOEM questioned the validity of using a regression analysis to make
the projections upon which decisions regarding active treatment will be based. RIOEM
specifically pointed to small sample size, statistical confidence in the coefficient of less
than 95%, and the elimination of outliers as critical faults in EPA's projection method.
RJOEM recommended that alternative bases for the aCtive treatment decision be
investigated.
EPA Response: EPA recognizes the limitations in utilizing a regression analysis to
predict the restoration time frames based on the data collected to date. Therefore,
EPA conctuded that the groundwater ~ rather than wiI~ be restored in a time frame
that is faster than that predicted by the model. However, based on further
investigations of statistical methods for comparing data. EPA has modified the method
for evaluating the effectiveness of natural attenuation. A statistical comparison of the
actual data to the theoretical data shall be conducted using the non parametric
distribution free signed rank test of Wilcoxon with a 95 percent significance as
described in NonDarametric Statistical Methods (by Hollander and Wolfe, published in
1973 by John Wiley, on pages 26-38). EPA believes that this approach eliminates any
. vagueness In the trigger for aCtive remediation as It relates to groundwater
contamination.
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Comment 30: RIDEM requested that statements indicating that the highest levels of
cont~n8!ion . are located in deep ponions of the aquifer and that bedrock
contamination was found in three wells rather than two be added to the Proposed
Plan: RJDEM ~ recommended that statements be added to the Proposed Plan
emphasizing that cleanup times in the Proposed Plan do not apply to bedrock.
..
EPA Response:. The statement that contamination was found in the deepest ponion
of the overburden aquifer was lOCated in the RJ Addendum in the Administrative
Record. As a public panlcipation document, the Proposed Plan need not contain all
the technical information contained in other repons. The Proposed Plan directed the
reader to review the Administrative Record for funher information. Based on EPA's
review of the information, there are only ~ wells lOCated in the deep ponion of the
bedrock system. As discussed in response to Comment 3, the tI:1ird well that RIDEM
is referring to is located in the upper fractured zone of the bedrock system and is not
indicative of the results of the deep ponion of the aquifer. EPA recognizes that the
cleanup times in the Proposed Plan are not indicative of the bedrock system.
Comment 31: RIDEM recommended that the Proposed Plan be amended to note
whether boring logs were examined for information on the residential wells; to propose
alternative sources for the domestic well contamination that was found; and, to note
whether evidence exists to substantiate any proposed alternative source of the
domestic well contamination.
EPA Response: The Proposed Plan notes that there was a lack of information on the
depth and method of construction of the residential wells. Hunt attempted to obtain
the well drillers' logs for the residential wells and determined that most of the current
residents did not have the well driller's log. Appendix 0 in the RI Repon contains a
summary of the information available on the residential wells and the source of the
information presented. In addition, as discussed in response to Comment 14, the
purpose of the RI was to characterize the extent of contamination from the Site not
from other sources beyond the Site. The extent of contamination in the overburden
aquifer has been well defined by the data collected during the RJ. However, funher
data must be collected to characterize the extent of contamination in the bedrock
system. Depending on the construction technique used to install the residential wells,
contamination from the bedrock system could be extracted into the residential well
and be a source d contamination in the residential wells.
Comment 32: RIDEM requested justification for the statement in the Proposed Plan
that many of the metals detected in Tarkiln Brook upstream from the Site may be
occurring naturally given that the upstream sampling lOCation is contaminated and
tt!erefore does not represent natural conditions.
EPA Re,pon,e: EPA has concluded that the principal contaminants in the
groundwater at the Site are VOCs. Therefore, a review of the results for VOCs in the
surface water serves as the best indication of which sampling lOCations are located
upgradient from the Site and which locations are lOCated downgradient from the Site.
Based on this review, EPA has concluded that three surface water and sediment
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sampling locations are located upgradient from the Site, STR1, STR2 and STR3. The
term "upgradient" refers to all the points upstream from the points where the
contaminated groundwater is discharging into Tarkiln Brook. EPA notes that the
resu~s ~om STR1 indicated the presence of a number of SVOCs and agrees that this
~Ion may not be Indicative 01 natural conditions. However, this is the only
upstream location that EPA knows to be contaminated. In addition, STR2 and STR3
were noI contaminated and are considered more representative 01 natural conditions.
Therefore, these points serve as a good comparison for the downgradlent locations
such as SUPL 1, STR4 and STR5. A comparison of the concentrations of metals in
STR2 and STR3 to SUPL 1, STR4 and STR5 Indicates that many of the metals detected
in all of these locations are of the same order of magnitude. Therefore, EPA has
concluded that many of the metals ~ be occurring naturally.
Comment 33: RIDEM stated that the Proposed Plan should indicate that the
conclusion that no contamination exists in the Reservoir is based on a "limited"
number of samples from the early 1980s and that some samples taken at that time
comained contaminants. Furthermore, RIDEM recommended that the Proposed Plan
state that the conclusion that contaminant levels in the Brook and Reservoir do not
pose a risk to public health was ~ased on a "limited" number of samples that did not
include any samples of fish flesh.
EPA Response: EPA is aware of the fact that samples of the Slatersville Reservoir
taken during the earlier history of the Site showed contamination. During the early
history of the Site, the source of contamination for the Reservoir, namely the
groundwater plume, was at ~s maximum extent and most likely extended into the
Reservoir. This conclusion is supported by the detection of contaminants in the
Reservoir at that time. However, as indicated by Figure 4 in Appendix A. the current
extent of groundwater contamination does not extend imo the Reservoir. Since the
source of contamination for the Reservoir has been significantly reduced, it is unlikely
that contamination currently exists in the Reservoir. This conclusion is also supported
by the surface water and sediment data collected during. the RI. One sample was
taken at the mouth of the Slatersville Reservoir during the currem RI and showed no
contamination. Therefore, additional samples of the Slatersville Reservoir were
determined not to be necessary.
EPA also recognizes that fish flesh samples were not taken. However, tests such as
this are typically not required by EPA unless the levels of contaminants in the surface
water and sediments are significantly higher than those detected at the Western Sand
& Gravel Site.
Comment 34: RIDEM requested documemed justification for EPA's selection of the
area to be covered by the access restrictions under the preferred alternative. RIDEM
. also "asf(ad whether EPA would protect any areas outside of the areas designated in
the Proposed Plan. RIDEM recommended that EPA outline mechanisms to protect
areas outside of the areas designated in the Proposed Plan if EPA does not already
plan to protect those areas.
WESTERN SAND & GRAVEL SUPERFUND SffE
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. .
EPA Response: The area requiring institutional controls, such as access restrictions,
. is presented in Figure 7 in Appendix A of the ROD. This area includes a buffer zone
which.iIIIows for a residential well to be installed without drawing contaminated
groundwater from the area which poses an unacceptable risk. This buffer zone is
equBJ to 300 feet at the Site. The risk to public health in this area is outside of EPA's
~eptable risk range of 1x10-4 to 1x10~. The risk to public health outside of the area
delineated in Figure 7 is within EPA's acceptable risk range. The documentation
which supports the risk calculations are presented in the RI Report. Furthermore, the
concentrations of contaminants beyond the area delineated in Figure 7 are below
ARARs. EPA is required under CERCLA and the NCP to select a remedy that is
protective of public health and the environment and which meets ARARs. Since the
risk posed to public health is within EPA's acceptable range and the levels of
contamination do not violate ARARs, EPA does not agree that Institutional controls
should also be placed beyond the area delineated in Figure 7. .
Comments on Hunt's Response to Previous RID EM Comments
on the Groundwater RI
Comment 35: The RI Report states that 'Rhode Island records indicate that an
estimated 419,000 gallons of septage waste was deposited...' at the Site. RIDEM
claims that this statement is not correct and requested that the report be corrected.
EPA Response: The documents generated by EPA correctly reflect the information
regarding historical disposal of waste. In summary, EPA has stated that RIDEM
records Indicate that about 470,000 gallons of waste were deposited at the Site during
its last year of operation.
Comment 36: RIDEM noted that the GZ3-2 well is a bedrock well screened in
bedrock, !!Qt in the overburden or highly fractured zone and that the Groundwater RI
be corrected to reflect that fact.
EPA Response: EPA disagrees with RIDEM's conclusion regarding the GZ3-2 well.
As discussed in response to Comment 3 above, a review of the well driller's log
indicates that this well is located in the fractured weathered zone of the bedrock
system.
Comment 37: RIDEM stated that Section 1.2, Site Description and History, of the
Groundwater RI Report should indicate that SVOCs and metals were found on the Site
in high concentrations. Furtherm~re, RII)EM requested that the Groundwater RI
Report note whether the Groundwater fS addresses potential off-site migration of
these contaminants.
EPA Response: EPA agrees that, during the early history of the Site, SVOCs and
metals were detected in the Site groundwater and soils. Therefore, EPA required Hunt
to conduct sampling for these compounds during the RI. Based on a review of the RI
30
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results, these compounds are no longer frequently detected or detected at elevated
concentrations. A review of the risk assessment indicates that the VOCs currently
pose the greatest heahh risk at the Site. Therefore, the VOCs are the focus of the
selected remedy. However, the selected remedy also includes periodic monitoring of
the $VOCs and metals to insure that these compounds continue to pose an
acceptable riSk to public health and the environment.
Comment 38: Regarding previous RIDEM comments on Sections 1.2, 2.2, and 2.3 of
the Groundwater RI, RIDEM noted its assumption that the information on the
completeness of the removal action at the Site was based on research on the subject.
If this is not the case, RIDEM recommended that certain statements on the matter be
deleted from the Groundwater RI and all statements on the removal process should be
based on the material requested by RIDEM.
EPA Response: Detailed information on the removal process conducted at the Site is
available for review in the Administrative Record. EPA acknowledges RIDEM's
comment but contends that this comment has no impact on the selected remedy.
Comment 39: RIDEM's original comment on Section 4.1 of the RI Report stated that
Hunt's evaluation of potential sources for the residential wells contamination (i.e. septic
systems) in addition to the Site were in error. RIDEM requested that Hunt provide
references for the information presented. Hunt responded by noting a report
generated by CDM in 1985. RIDEM could not find the reference cited by Hunt and
requested that Hunt provide the proper references.
EPA Response: EPA agrees with RIDEM that the evaluations and conclusions
regarding septic tank contamination in the residential wells is not supported by the
information provided by Hunt in the RI Report. However, this conclusion does not
impact the selected remedy.
Comment 40: RIDEM noted that, according to the Cap Closure Final Report, the
proposed contaminated material removal included soils. RIDEM stated that, therefore.
the Groundwater RI had not addressed RIDEM's previous comments and the report
should address the contaminated material not removed from Pit 13.
EPA Re.pon.e: Based on EPA's review of the information, the purpose of RID EM's
comment Is not ctear. Comments on the closure work are not directly applicable to
the Groundwater RI. It is evident from the results of the groundwater investigation that
the source of contamination has been minimized. The post-closure plan for the cap
requires continued monitoring m the groundwater to Insure that the cap continues to
effectively control any remaining source ~ c~amination.
Comment 41: RIDEM commented on the Draft RI Report and noted that Section 7.3
of the RI Report should identify the average depth to groundwater. RIDEM's review of
the Revised RI Report indicated that the report was not revised accordingly.
WESTERN SAND & GRAVEL SUPERFUND SITE
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.
EPA Response: EPA's review of the Groundwater RI Report indicates that
groundwater is found at depths ranging from 3 feet below grade to 28 feet below
grade; -
.
..'
-
Comment 42: RIDEM noted that Hum had failed to address RIDEM's previous
eommem on Section 7.4, page 123, 7th paragraph. RIDEM's commem was as follows:
The report should incfude a statemem to support the conclusion that
.groundwater monitoring during the currem GRI evidenced that absence of
NAPL in the aquifer.. This would include the method employed for detecting
NAPL and a summary of the obtained results. Table 1-1, page 1-7 of the 1984
RIIFS comains an analysis of NAPL found at the Site. Information comained in
Appendix K indicates that a number of compounds, previously idemified in the
analysis of NAPL., are still being detected.
EPA Response: As discussed in response to Commem 8 above, the concentration
of comaminams at the Site are not indicative of the presence of NAPLs. Groundwater
concemrations of 5 to 10 percem of the field solubility of a compound is thought to
suggest the presence of NAPLs. The concentrations of comaminams at the Site
curremly do not approach this level. However, in response to RIDEM's concern, the
selected remedy includes the use of an interface probe to idemify the presence of
NAPLs. This test shall be conducted during the first round of groundwater sampling
and shall confirm the conclusion.
Comment 43: RIDEM noted that Hum had failed to address RIDEM's previous
commem on Section 7.4, page 124, 2nd paragraph. RIDEM's comment was as
follows:
RIDEM noted that for completeness the RI Report should include a statement
concerning the historic information for alcohols in monitoring wells.
EPA Response: Alcohols were detected at elevated concemrations in the
groundwater during the early history of the Site. Therefore, EPA requested that Hunt
conduct analyses for alcohols during the RI. The results of these analyses indicate
that alcohols do not currently pose a significant risk to public health and the
environment at the Site.
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Part III - Summary of Potentially Responsible Party Comments
..
Olin Hunt Specialty Products, Inc., (Hunt), a potentially responsible party the
Site, provided written comments which are summarized below.
Comment 1: Hunt recommended that the ROD allow flexibility in the approach to be
used to prevent human exposure to the contaminated groundwater. Hunt
recommended that the ROD allow for either an alternate water supply, such as
extension of the existing system under construction or well head treatment. or
implementation of groundwater access restrictions, such as deed restrictions or
purchasing the property or groundwater rights. Hunt believes that these methods can
effectively protect public health and notes that they have been used at other
Superfund sites. Hunt states that the ROD should not require specifically the
purchase of property to achieve this protection.
EPA Response: The selected remedy in the ROD requires the implementation of
institutional controls necessary for preventing exposure to the contaminated
groundwater within the area delineated in Figure 7 in Appendix A. The ROD states
that the institutional controls shall be implemented to reduce the risk to public health
from consumption of the groundwater. Such controls may include regulatory
restrictions, acquisition of affected properties or groundwater rights. and other
restrictions on property transactions. An alternate water supply, such as well head
treatment of expansion of the existing permanent water supply is not considered an
effective means to prevent access to the groundwater. Furthermore. expansion of the
existing system is not feasible without additional investigations to identify a source.
There are 45 existing residential homes in the affected area Of these 45 residences,
41 residences participated in the well head treatment program making this program 91
percent effective at preventing exposure to the groundwater. To date. 44 residences
have provided EP A with access agreements to connect to the permanent water supply
making this program 98 percent effective at preventing exposure to the groundwater.
While theSe percentages seem high, EPA does not consider these programs fully
effective at eliminating exposure to the groundwater.
The affected area Identified In the 1984 ROD included 56 parcels of land. An
investigation was conducted by Camp Dresser and McKee in 1985 to identify a source
for the water system assuming a 60 lot capacity. A pump test was conducted at the
source that was finally selected. COM concluded that the source selected for the
. water system had the capacity to service 60 residential lots. COM further stated that,
In the event d expansion beyond the 60 lots, additional data should be collected to
determine . the source had the capacity to service additional lots. After issuance of
the ROD, 9 additional lots on Douglas Pike were included in the consent decree as
part of the affected area resulting in a total of 65 lots within the affected area Since
the issuance of the ROD. some of the lots within the affected area have subdivided.
Currently. there are approximately 72 lots in the affected area Therefore, the capacity
WESTERN SAND & GRAVEL. SUPERFUND SfTE
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of the existing system is already consumed by the existing lots. Excess capacity is
not available for future subdivisions without additiOnal investigations. Therefore,
additi~nci!. investigations would have to be conduded to verify if the existing source
has the capacity to service any additional lots including those created by subdividing
the..1ots idemi!led in Figure 7 in Appendix A.
1ft summary, since the provisions of an alternate water supply is not 100 percent
effective at preventing exposure to the groundwater at the Site, EPA believes that
institutional comrols are also needed.
Comment 2: Hum agreed to install and sample additional bedrock wells. Hunt
stated that this work will more than adequately characterize the bedrock system and
should be the final phase of bedrock investigations. . ..
EPA Response: In a letter dated February 7, 1991, EPA requested that Hunt conduct
additional investigations of the bedrock system. These investigations included the
installation of three new bedrock wells. EPA does not agree with Hum's statement
that "this work will more than adequately characterize the bedrock system.. EP A
considers this conclusions premature. As stated in the February 7 letter, EPA
considers this work the first phase of the investigation. EP A shall determine if
additional investigations shall be conduded after reviewing the results from the first
phase of the investigation.
Comment 3: Hum believes that the existing data adequately characterizes the
surface waters and sedimems of Tarkiln Brook. Furthermore, Hum believes that the
results show that Tarkiln Brook is not experiencing significam environmental stress due
to Site comaminams. Hum contended that it has attempted to address all previous
concerns of RIDEM on this matter. Hunt requested further opportunity to address
specific RIDEM concerns regarding the Brook, including meetings with RIDEM.
EPA Response: EPA encourages Hum to cooperate with RIDEM in resolving the
issues ~ociated with the investigations of Tarkiln Brook. EPA will evaluate any
additiori~' data :ollected by Hum and determine tf modifications to the selected
remedy are necessary for the protection of the public health and the environment.
Comment 4: Hunt noted that the preferred alternative appears to propose sampling
from aU existing Groundwater RI and Site closure monitoring wells. Since the plume of
contamination Is already well defined, Hum believes that the plume can be adequately
monitored by a subset a the wells scheduled for future sampling in the preferred
alternative. Hunt proposed a specific subset of the welts and a monitoring schedule
for EPA's consideration. Hum noted that using a subset a the wells for monitoring the
plume would be consistem with past EPA and RIDEM practices at the Site. Hum also
recommended that the ROO allow for modification of the monitoring program based on
new sampling data as it is accumulated during the course of the remediation.
EPA Respon.e: EPA evaluated the groundwater monitoring plan for the overburden
aquifer in the FS Addendum and the Proposed Plan and has modified the monitoring
34
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plan based on comments received from RID EM and Hunt. The modified overburden
groundwater monitoring program is as follows:
.
The following twenty eight (28) wells shall be monitored on a quarterly
- basis for volatile organic compounds (VOCs) and on an annual basis
for semi-volatile compounds (SVOCs) and metals.
C-1 C-3S C-SS 1-2$ 1-68
C-2$ C-3M C-5M I-2M I-6M
C-2M C-3D C-5D 1-20 I-6D
C-2D C48 C-68 103$ I1-3S
C-4M C-6M I-3M I1-3M
C-4D .C-60. 1-30 I1-3D
A review of the analytical data presented in the AI Report indicated
that, with the exception of C-1 which is upgradient of the Site, these
wells were the most contaminated wells in the plume (See Figure 4.2
in At Repott, Hn. June 1990). All of these wells shall be utilized to
evaluate the eftectiveness of natural attenuation. Quarterty monitoring
in needed to provide enough data to statistically evaluate the
effectiveness of natural attenuation. In addition, it is anticipated that
the probability of implementing active restoration is the greatest in the
first six (6) years. Therefore, quarterty monitoring must be conducted
for a minimum of six (6) years. .
VOCs are the most prevalent compounds detected at the Site.
However, some SVOCs and metals have also been detected in the
groundwater. Based on EPA's review of the data. these compounds
are not expected to increase in magnitude and extent. However, due
to concerns raised by RIOEM on the imP8CtS to Tarkiln Brook and in
order to verify this conclusion, annual monitoring of SVOCs and metals
has also been included in the monitoring plan. After a minimum of
three years of monitoring, the monitoring plan may be modified to
reduce the frequency of sampling if approved by EP A.
.
In addition, the following twenty eight (28) wells shall be monitored on
an semi-annual basis for VOCs.
1-1S I-SS 1-85 1148 11-68
I-1M 1-5M I.;8M I1-4M 11-6M
1-10 I-50 1-80 11-40 11-60
148 1-7S 11-2$ II-SS
14M 1-7M II-2M 11-5M
1-40 1-70 11-20 II-50
These wells were found to be in the overburden plume or just outside
of the plume during the RI. As stated above, EPA has concluded that
the magnitude and extent c:A contamination in the overburden aquifer
is decreasing. In addition, EP A has concluded that there is a small
component of flow which passes under Tarkiln Brook and discharges
into the Slatersville Reservoir. This conclusion is based on seven
WESTERN SAND & GRAVEL SUPERFUND SITE
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.
.. -.-
sampling episodes over a two and a half year period. However, due
. to concerns raised by RIDEM on the potential impacts to the Reservoir,
this conclusion shall be verified with additional long-term data. After a
minimum of three years of monitoring, the monitoring plan may be
- modified to reduce the frequency cI sampling if approved by EP A
In summary, EPA considered Hunt's comments on the monitoring program.
EPA has concluded that based on the data collected to date, the magnitude
and extent of the overburden groundwater plume appears to be decreasing.
This conclusion supports EPA's selection of natural attenuation with contingent
active restoration. Immediate implementation of active restoration would insure
that the magnitude and extent of the plume would continue to decrease.
Since active restoration shall not be Implemented immediately, a
comprehensive monitoring plan is needed to verify this conclusion.
Furthermore, due to concerns raised by RIDEM on the Impacts to Tarkiln
Brook and the Slatersville Reservoir, long-term monitoring of SVOCs and
metals has also been included in the monitoring plan.
Comment 5: Hunt noted that tr~e Slatersville Aquifer is not a single regional aquifer
as implied in the Proposed Plan, but Is divided into several discrete units. Hunt
concluded that contamination in one unit will not impact other units. In addition, Hunt
emphasized that only a small portion of the aquifer in the area of the Site is impacted
by contamination from the Site.
EPA Response: EPA agrees that the Site has currently impacted one portion of the
SJatersville Aquifer. However, future impacts to the other portions of the aquifer will
depend upon future conditions around the Site. According to the investigations of the
Slatersville Aquifer conducted by the U.S. Geological Survey, a public water supply
located along the east bank of the Slatersville Reservoir With a pumping rate of 1000
gpm would have a cone of influence which extends about 5000 feet A cone of
influence of this size would impact the hydrogeology of the Site. In addition, a local
utility recently requested comments from EPA on the use of another portion of the
Slatersville Aquifer for the purpose of providing a source of cooling water. Future
changes in the use cI the aquifer such as this could also result in changes to the
hydrogeology at the Site. Therefore, EPA believes that it is possible that additional
portions of the Slatersville Aquifer could be impacted by the Site If the hydrogeological
conditions surrounding the Site are altered.
During the public hearing, RIDEM presented comments on EPA's Proposed Plan as
well as the other documentS in the Administrative Record. As pan 0' Hunt's comments
on the Proposed Plan, Hunt submitted responses to RIDEM's comments at presented at
the public hearing. Hunt's responses are presented in comments 6 through 10.
Comment 8: RlDEM stated that the assessment of the impacts to Tarkiln Brook were
inconclusive and that additional data is required and should be collected prior to
finalization of the ROD. In response to this comment, Hunt notes that the Proposed
Plan retains a provision for RIDEM to request additional surface water and sediment
36
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.
data. Hunt stated that the existing data is sufficient to characterize Tarktln Brook and
requests further opportunity to address specific concerns.
"
EPA Re.pon.e: As stated in EPA's response to Comment 3 in Part III of this section,
EPA..encourages Hunt to cooperate with RlDEM in resotving the issues associated with
thQ investigations of Tarkiln Brook. EPA will evaluate any additional data collected by
Hunt and determine if modifications to the selected remedy are necessary for the
protection of the public heatth and the environment.
Comment 7: RIDEM stated that the bedrock investigation was inconclusive and that
additional data should be collected prior to finalization of the ROD. In response to this
comment, Hunt noted that the Proposed Plan retains a provision for the Agency to
request additional data on the bedrOCk system. Furthermore, Hunt notes that EPA has
already requested that Hunt collect additional data. In response to this request, Hunt
has agreed to install and sample additional bedrock wells.
EPA Response: EPA believes that the issue of bedrock contamination can be
addressed after issuance of the ROD. Hunt has agreed to collect additional bedrock
data Alter reviewing the results at this investigation, EPA shall determine if additional
investigations are necessary or if the selected remedy should be modified to include
active restoration and/or 'ong-term monitoring of the bedrock system.
Comment 8: RIDEM had concems regarding the validity 01 the groundwater model
used in the Groundwater FS for predicting the time of restoration. Hunt noted that the
same model was used to evaluate both natural attenuation and active restoration and
thus provided a fair basis for a relative comparison of the two remedies. Hunt added
that field data have shown that natural attenuation is actually reducing contaminant
concentrations and shrinking the plume faster than predicted by the model.
EPA Response: EPA's responses to RIDEM's specific concerns with the model are
presented in EPA's response to Comment 4 in Part II of this section. In summary, EPA
has concluded that the model presents a conservative estimation of the actual time for
restoration of the groundwater. This conclusion is supported by the actual data
collected to date. In addition, since the same assumptions were utilized, the model
was an accurate tool for comparing the effectiveness of natural attenuation to active
restoration.
Comment I: RIDEM stated that selection of natural attenuation is not consistent with
the State of Rhode Island's statutory program regarding groundwater protection. In
response to RIDEM's assertion, Hunt contended that the Groundwater Protection Act
does not contain a mandaIe Of preference for active restoration over natural
attenuation where, as in this case, natural attenuation is as effective and as efficient as
active treatment at reS1lOring groundwater quality. Hunt also argued that, since RIDEM
has not formally adopted a groundwater classification system or any other regulations
relating to groundwater classification, natural attenuation does not conflict with RIDEM
policy. Hunt added that active treatment may not be any faster than natural
WESTERN SAND & GRAVEL SUPERFUND SITE
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.
attenuation because the rate at which the contaminants will be released from the
aquifer soils may limit the speed of restoration regardless of the quantitY of water
pumped.
.. -
EPA R..pon.e: EPA's complete response to this comment is presented in response
to COmment S. in Part II of this section. In summary, EPA believes that selection of
natural attenuation is consistent with the State's Groundwater Protection Act. The
..
Groundwater Protection Act mandates the State to promulgate cJassification standards
and regulations for the protection and restoration of aquifers in the State of Rhode
Island. Those standards and regulations have not been promulgated to date.
According to the Draft Groundwater Protect Standards, the groundwater at the
Western Sand & Gravel Site is classified as GAA-nonattainment. Class GAA-
nonattainment requires the groundwater to be restored to drinking water s.tandards. .
EPA's selected remedy shall restore the groundwater to drinking water standards
using natural attenuation within 24 to 28 years. This time-frame is appropriate given
the particular circumstances at the Site. EPA has determined that the GWPA does not
require active restoration of the groundwater at the Site.
EPA does not agree with Olin's conclusion that the desorption rate of contaminants
from aquifer soils may be the rate limiting step in restoration of the aquifer. The
desorption rate of contaminants is based on the organic content of the soils.
Contaminants tend to bind to soils with high organic content. The aquifer soils at the
Western Sand & Gravel Site consist primarily of sand deposits which contain a low
organic content. Therefore, EPA has concluded that it is unlikely that the desorption
rate shall be the rate limiting step in restoring the groundwater at the Site.
Comment 10: RIDEM stated that the decision mechanisms for contingent active
restoration which are based on the groundwater monitoring results were vague.
RIDEM further requested that detailed criteria for groundwater, surface water and
sediments were needed. In response to this comment, Hunt stated that the selection
of an appropriate monitoring program should not be a factor in the decision between
remedies since an adequate monitoring program will be required in any case.
EPA Re.ponse: EPA agrees with the State that the decision mechanism for
implementation of active restoration should be specified in detail. EPA disagrees with
Hunt that selection of a monitoring program should not be a factor in the decision
between remedies. Selection of naturaJ attenuation with COntingent active reStoration
was highly dependent on whether an effective monitoring and evaluation program
could be developed. If an effective program could not be developed, the preferred
alternative could not be implemented and the selection of a remedy at the Site would
have been between either natural attenuation without active restoration or active
restoration Itself. In response to RIDEM's comments on the monitoring and evaluation
pIa~ iEPA reviewed the program established to evaluate the effectiveness of natural
attenuation In the preferred alternative and has modified the monitoring and evaluation
program. A discussion of the revised program is presented in response to Comment
61n Part II of this section. EPA believes that the revised program shall be effective in
detennining whether natural attenuation Is reducing the concentrations of
38
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contaminants at the Site within a time frame which is reasonable given the particular
circumstances at the Site.
-
Comment 11: RIDEM stated that they had concerns about access restrictions for
fut~ ~ Hunt responded to this statement by noting that Hunt believes that
pubnc health can be protected by provision of an alternate water supply and/or
aCcess restrictions. Furthermore, Hunt noted that protection of public health has been
accomplished at other Superfund Sites using these methods.
EPA Response: EPA believes that institutional controls, such as access restrictions,
are a necessary component of the selected remedy. As discussed in response to
Comment 1 In Part 11/ of this section, provisions for an alternate water supply are not
considered effective and are not acceptable as a form of Institutional controls.
Comment 12: Hunt stated that it had received verbal comments from the Nasonville
Water District indicating that the Water District prefers an active restoration remedy
based on current problems with activation of the new permanent water supply. Hunt
argues that the seJection of a groundwater remedy for the Site should be kept
independent of disagreements related to the water supply. In addition, Hunt noted
that no technical barriers exist to' the operation of the water supply at this time.
EPA Response: The U.S. Army Corps of Engineers has indicated the permanent
altemate water supply is certifiably complete and operational. EPA has been working
towards resolving the issues associated with operation of the permanent water supply
and does not believe that these issues impact the selection of the remedy for the
groundwater contamination.
Comment 13: Hunt noted that the Groundwater RI Addendum should state that data
from the closure wells were used to aid in defining Site hydrogeology.
EPA Response: The AI Addendum states that "forty two wells were installed at
varying depths and fifteen locations in the overburden aquifer during the RI.' EP A
acknowledges Hunt's correction to this statement. The RI Addendum should also note
that in addition to the forty two wells, sixteen wells, also known as closure wells, were
installed at six locations around the perimeter of the cap. These wells were installed
to monitor the effectiveness of the cap. Data from these wells was also utilized to
characterize the hydrogeology of the Site.
Comment 14: Hunt believes that the decrease of contamination concentration with
distanCe from the Site should be described in the Groundwater AI Addendum as
"rapid" or "significant" rather than "gradu~' ~
EPA Respon.e: EPA believes that adjectives such as rapid, significant or gradual are
difficult to define and are subject to the opinion of the reader. The important fact to
note Is that the concentrations of contaminants at the Site decrease with distance from
WESTERN SAND & GRAVEL SUPERFUND SfTE
-------
.
the Site. The readers of the addendum can review the figures and make their own
judgement as to whether the decrease in concentration is gradual, rapid or significant.
..
Com.ment 15: Hunt commented that the bedrock sampling well seals were not
'aulty-, but were property designed and installed. Hunt noted that even if the well
seaJs were completely effective, artificial gradients induced by well evacuation may
cause migration of contaminated overburden groundwater through natural fractures to
the bedrock well screens. Hunt stated that this is a limitation of the best technology
available today for monitoring well construction.
EPA Response: EPA agrees with Hunt that the wells may have been installed
correctly. However, the wells were 'autty- in meeting the objective for which they were
installed. The objective of installing the bedrock wells was to characterize the extent
of contamination in the bedrock systems. Since the well seal may not have effectively
prevented contaminated groundwater from the overburden aquifer from entering into
the bedrock well, the wells were faulty in meeting the objective of the bedrock
investigation. Furthermore, EPA believes that the problems encountered during the
installation and monitoring of the existing bedrock wells can be eliminated with the use
of an open bore hole and sampling methods capable of isolating the discrete intervals
within the borehole.
Comment 16: Hunt disagrees with the conclusion that production from residential
bedrock wells indicates that there is a substantial flow of groundwater in the bedrock
fracture network near the Site. Rather, Hunt contends that a significant portion of
residential bedrock well water is likely from the overburden.
EPA Response: Hunt has not provided evidence to support their conclusion that the
primary source of water for the residential bedrock wells is actually overburden
groundwater. EPA believes that it is more likely that the source of water for the
bedrock wells is actually from water bearing fractures in the bedrock system. EPA's
conclusion seems reasonable when considering the approach taken to install
residential wells. Typically, a well driller installs wells to a depth necessary to obtain a
sufficient yield of water. If the well driller had identified a sufficient yield in the
overburden, the driller would have stopped drilling and left the well in the overburden
aquifer. If the driller does not encounter sufficient yield In the overburden, the driller
continues drilling into bedrock until a water bearing fracture Is found. The conclusion
is further supported by the fact that most of the known residential bedrock wells are
located In proximity to one another. One possible explanation for this occurrence is
the Jack d a source of overburden groundwater in this general area. Therefore, EP A
does not agree that the source of the water in the residential bedrock wells is
t:'Verbllrden groundwater.
Comment 17: Hunt disagrees with the conclusion that contamination In residential
bedrock wells indicates that the bedrock system may also be contaminated. Hunt
contends that, since the bedrock wells receive substantial recharge from the
overburden, they can also receive contamination from the overburden such as septic
40
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system contamination. Hunt noted that additional data will 'determine if the bedrock
system is contaminated,' not 'verify that the bedrock system is contaminated.'
EPA Re.ponse: As noted above in response to Comment 16 in Part III of this
section. Hunt has not presented evidence to prove that the residential bedrock wells
receive substantial recharge from the overburden. In addition, Hunt has not presented
evidence to support the conclusion that the source of contamination in the bedrock
wells is septic systems. Based on the data collected to date, it is premature to
eliminate the Site as a possible source of contamination in the residential bedrock
wells. Furthermore, as discussed in the RI Addendum, there are two explanations for
the contamination detected in the bedrock system One explanation is that the
groundwater migrated under natural conditions and contaminated the wells. The other
explanation is that the contamination resulted from artificially induced vertical
migration. .
Comment 18: Hunt had three comments on Figure 2 in the RI Addendum which is a
contour map based on piezometric data. First, Hunt noted a correction in the
presentation of the data. Hunt noted that the piezometric elevations should be
presented as 256.1 rather than 56.1. Second, Hunt stated that the piezometric map
should be prepared with the water levels of Tarkiln Brook. Finally, Hunt noted that the
area indicated as the 'Minimum Extent of Plume' should be identified as the 'Minimum
Potential Extent of Plume.'
EPA Response: EPA acknowledges Hunt's first comment on the presentation of the
piezometric information and has concluded that it has no impact on the conclusions
drawn by EPA on this figure. The numerical values for the piezometric data were
presented in abbreviated form due to limited space available on the map. Second,
EPA disagrees with Hunt's conclusion that the water levels of Tarkiln Brook should be
included in the piezometric map. As stated in the RI Addendum, there is a component
of flow in the deep portion of the aquifer which passes under the Brook (emphasis
added). The appropriate way to assess the direction of this component of flow is to
map the piezometric elevations without the water levels in the Brook. Finally, EP A
agrees with Hunt's comment that the area on Figure 2 should be identified as
'Minimum Potential Extent of Plume.'
Comment 19: Hunt noted that it is not certain whether residents who are not
participating in the residential well treatment program are being exposed to Site
contaminants.
EPA Re.pon.e: EPA acknowledges Hunt's comment that residents who, by their
own choice, are not participating in the residential well treatment program, may be
exposed to Site contaminants in the groundwater. Since the residents are not
participating in the residential well treatment program. data on the quality of the water
In their wells is not available.
WESTERN SAND & GRAVEL SUPERFUND SITE
-------
9 .
Comment 20: Hunt stated that the intent of further bedrock investigation is to identify
and monitor any productive zones. However, Hunt notes that it will be difficult to
compl~ely prevent inducing artificial gradients between the overburden and the
bedrock. -In addition, Hunt noted that evacuation of the bedrock will be required for
relJJ()Val of drilling water and, determination of yield, and/Ot sample event purging.
Such evacuations will unavoidably induce some artificial vertical gradient if the
~reened interval is an essentially non-water bearing zone.
EPA Response: EPA believes that the critical element in inducing artificial gradients
In bedrock wells is the sampling methods not the well installation methods. Sampling
from discrete ten foot intervals, continuously through the length of the borehole, will
not cause artificial gradients. Utilizing this approach fOt sampling would allow
sampling of discrete zones with adequate purging even if the entire borehole was. not
able to be developed.
Comment 21: Hunt argued that active restoration of bedrock groundwater is not
feasible due to low yield and the likelihood of drawdown of contaminated groundwater
from the overburden.
EPA Response: EPA disagrees with Hunt's conclusion that the bedrock at the Site is
low yielding. This conclusion is based on the results from two wells and may not be
indicative of conditions throughout the Site. Therefore, EPA also disagrees with the
conclusion that active restoration of the bedrock system may not be feasible. EPA
believes that sufficient data has not been collected to adequately characterize the
bedrock system and that it is premature to draw conclusions on the limited data
collected from the two bedrock wells.
Comment 22: Hunt disagreed with EPA's interpretation of the definitions of long- and
short-tenn effectiveness as described in EPA's comments on the Groundwater FS and
in the FS Addendum. Hunt argued that short-term effectiveness covers the time up to
the point where cleanup levels are achieved. Furthermore. Hunt asserts that their
discussion of ARARs was complete. Hunt recognized that the cleanup levels would be
finalized at the time of the ROO. However, Hunt provided EPA with the opportunity to
comment on the cleanup levels listed in Table 2.2 in the Draft deliverables.
EPA Response: Hunt's response asserts that in its discussion of ARARs in its FS
report it has complied with S 300.430 (e) (9) Oi~ (8) of the NCP. That section
describes how the Detailed Analysis section of the Feasibility Study must assess
whether each proposed remedy attains applicable or relevant and appropriate
requirements (ARARs). The Preamble to that section states thar[t]he detailed analysis
should summarize which requirements are applicable or relevant and appropriate to
an alternative and deScribe how the a~emative r,leats these requirements.. The
Detailed Analyses of Alternatives 1, 2 and 3 merely state that those alternatives "will
achieve compliance with ARARs.. This statement falls well short of the level of detail
required by the NCP. The analyses of Alternatives 4 and 5 are also incomplete, in that
they do not summarize the ARARs affecting those alternatives or adequately describe
42
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. .
how each alternative meets those ARARs. The NCP requires that such discussion
occur specifically within the Detailed Analysis section.
EPA.understands Hunt's response that the ARARs for alternatives 1, 2, 3, 4 and 5
w" presented in Table 2.2. However, this table was not referenced at any point
during the discussion of AAARs in the Detailed Analysis or the Comparison of
.Alternatives. Moreover, the groundwater modeling which Hunt refers to as identifying
how each alternative will comply with chemical-specific AAARs is not mentioned in any
ARARs discussion in the report. Finally, while EPA agrees that additional ARARs for
Alternative 4 were listed in the Comparison of Alternatives ARARs discussion, EP A
believes that these ARARs would have been equally applicable to Alternative 5.
However, Hunt does not even mention Alternative 5 in the ARARs discussion of the
Comparison of Alternatives. .
Comment 23: Hunt contends that the residual risk could not be identified in the FS
Report because the finaf clean-up levels had not been selected by EPA. Hunt stated
that the residuaf risk would equal that associated with the dean-up level chosen by
EPA and that risk would be protective of human health. Furthermore. Hunt states that
the analysis of the long-term effectiveness and permanence criteria should, according
to the NCP, "ocus on any residual risk remaining at the conclusion of the remedial
actions. .
EPA Response: EPA believes that Hunt may have used ARARs in calculating
residual risk at the Site. Regardless of whether residual risk could be identified in the
Feasibility Study, the remedy selected in the ROO provides that residual risk will be
determined only when ARARs are met and a risk assessment is conducted.
EPA understands Hunt's concerns regarding the analysis of long-term effectiveness.
Due to the stated preference for active treatment in the NCP, short-term effectiveness
and long-term effectiveness as defined in the NCP are difficult to apply in a remedy
using natLral attenuation. The clear distinction between an active remedial period and
the residual risk after treatment is completed does not exist for a natural attenuation
remedy: However, EPA believes that it has property addressed long-term
effectiveness ar.d short-term effectiveness in light of the circumstances of this remedy.
Comment 24: Hunt requests justifiCation for EPA's conclusion that a 300-foot
hydrogeological racjius of influence exists around residential wells.
EPA R..pon.e: EPA believes that the 300 foot buffer zone within the area requiring
institutional controls is reasonable. According to Rhode Island' rules and regulations
pertaining to groundwater protection (R46-13-0WQ). a 400 foot radius of protection is
required for a gravel developed domestic well and a 200 foot radius of protection is
required for a drilled domestic well.
WESTERN S~D & GRAVEL SUPERFUND SITE
-------
.
IV.. Remaining Concerns
... Issues raised during the public comment period that will continue to be of
concern as the Site moves into the RD/RA phase are listed below. EPA will continue
too address these issues as more information becomes available during the RD/RA.
1
The public will remain concerned over the progress of the natural attenuation,
especially in the first few years. Residents will wish to be informed of the
results of the monitoring and the evaluations. Special attention may need to
be paid to explaining how the evaluations are perform~.
2.
Potential contamination of the bedrock and surface water will also remain
important concerns to the public at least until the results of the additional
studies of these media have been published.
Community interest in the Site may rise due to remedial activity at neighboring Sites
such as Stamina Mills and LandfiU & Resource Recovery.
44
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..
.
Attachment A
Formal Community Relations Activities Conducted To Date
at the Western Sand & Gravel Superfund Site
2 April 1980
30 September 1981
September 1982
29 December 1982
23 February 1983
6 April 1983
23 November 1983
12 December 1983
23 December 1983
28 December 1983
23 January 1984
23 January 1984
EPA Press Release conceming EPA and .RIDEM
announcement that PCBs have been discovered in material
taken from an industrial waste lagoon on. the Site.
RIDEM status letter to Town Council.
RIDEM Community Relations Plan.
Burrillville Town Council appoints Coordinating Committee
(Ethel Halsey, Chair) to work with RIDEM. as suggested by
former RIDEM Director, Ed Wood, in 9/30/81 letter to Town
Council.
RIDEM status letter to Ethel Halsey, including copy of RIDEM
quarterty status report to EP A covering 7, 8, & 9/83.
EPA Press Release conceming a study to determine the extent
of chemical contamination in groundwater.
Letter from John P. Hartley, RIDEM, to Ethel M. Halsey, Protect
Our Water, conceming an update on state and EPA activities
at the Site, with attached Progress Report. RIDEM, July -
September 1983.
RIDEM status Jetter to Burri/lville Building Inspector
EPA Press Release regarding filing of administrative complaint
against president and owner of Westem Sand & Gravel, Inc.
for violation of Federal Hazardous Waste Management laws.
Letter from John P. Hartley, RIDEM, to Ethel M. Halsey, Protect
Our Water, conceming progress on the cleanup, the RIIFS,
and installation of a new pumping well at the Site.
EPA newspaper advertisements in the Providence Joumal and
Woonsocket Call announcing the availability of the Feasibility
Study and preferred altemative (water supply construction),the
public comment period, and two scheduled public meetings.
EPA Press Release regarding scheduled Public Meetings on
-------
February 1984
2 Fe~(UIUY 19~
.
2 February 1984 -
7 March 1984
6 February 1984
14 February 1984
16 February 1984
23 February 1984
(during comment
period)
February 1984
24 February 1984
27 February 1984
27 February 1984
29 February 1984
. 29 February 1984
.
EPA Press Release announcing Hunt Proposal for residential
water filters.
EPA and RIDEM public meeting on the Feasibility Study and
EPA's preferred alternative (water supply construction).
Recording of meeting available for review at EPA Region I.
EPA public comment period on the Feasibility Study and
preferred alternative (water supply construction).
EPA Press Release announcing. change of public meeting from
219/84 to 2123/84, and the extension of the close of the
comment period to 2129/84.
- Letter from Christine J. Spadafor, EPA Region I, to Ethel M.
Halsey, Protect Our Water, concerning assistance in
structuring public comments on the RI/FS.
Letter from Christine J. Spadafor, EPA Region I, to Ethel M.
Halsey, Protect Our Water, concerning requested sections of
the RIIFS.
EPA and RIDEM informal public hearing to accept comments
on the Feasibility Study and preferred alternative. Recording
of hearing available for review at EPA Region I.
Two EPA informal meetings with the Western
Sand & Gravel Hazardous Waste Coordinating Committee to
answer questions and receive comments on the Feasibility
Study and preferred alternative.
EP A Press Release regarding second extension of comment
period, until 317/84. .
Memorandum from Christine J. Spadafor, EPA Region I, to
Ethel M. Halsey, Protect Our Water, concerning requested
sections of the RIIFS.
RIDEM letter to WSG Coordinating Committee wI RIDEM
comments on RIIFS.
Letter from John P. Hartley, RID EM, to Ethel M. Halsey, Protect
Our Water, concerning follow-up for the 2123/84 public
meeting.
Memorandum from Christine J. Spadafor, EPA Region I, to
Ethel M. Halsey, Protect Our Water, concerning follow-up for
the 2123/84 public meeting.
Letter from John P. Hartley, RIDEM, to Arthur Denomme, North
Smithfteld Town Administrator, and to the Town Clerk,
concerning the timetable for public comments and the Record
-------
20 April 1984
28 ~sptember .1984
15 October 1984
27 November 1984
6 December 1984
18 December 1984 -
8 February 1985
August 1985
12 August 1985
August 1985
20 August 1985 -
13 September 1985
21 August 1985
27 August 1985
4 September 1985
9 September 1985
30 September 1985
.
Letter from John P. Hanley, RIDEM, to Ethel M. -Halsey, Protect
Our Water, concerning the status of the RI/FS and other Site
activities.
EPA Responsiveness SummarylRecord ~ Decision on water
supply construction.
EPA Press Release announcing the Record of Decision (water
supply construction).
EPA Press Release regarding $1000 fine levied against WSG
for failure to respond to information request from EPA.
EPA Press Release concerning EPA's review of Hunt's
proposal for water filters.
Letter from Jack W. McGraw, EPA Headquarters, to Ethel M.
Halsey, Town of Burrillville, concerning the authorization of the
design of an alternative water supply and the next phase of
remedial. action.
EPA Press Release concerning EPA citing ACME Services
owner.
EPA information sheet about the domestic water filter systems
and sampling program.
EPA Press Release announcing Site capping Proposed Plan,
8/27/85 public meeting, 9/10/85 public hearing, and public
comment period closing 9/13/85.
EPA fact sheet about the Feasibility Study and preferred
alternative (Site Capping).
EPA public comment period on the Feasibility Study and
preferred alternative (Site Capping).
EPA meeting with the Western Sand and Gravel Coordinating
Committee to discuSS the Feasibility Study, EPA's and
preferred alternative, and upcoming public meetings.
EPA public meeting on the Feasibility Study and preferred
alternative.
RIDEM public notice on site public meeting concerning the
proposed creation of the Nasonville Waster District.
EPA informal public hearing on the Feasibility Study and
preferred alternative.
EPA Responsiveness SummarylRecord of Decision, Site
-------
1 October 1985
21 FfbtuBry 1986
...
5 March 1986
19 May 1986
9 October 1986
14 November 1986
14 November 1986
15 December 1986
24 Apri/1987
4 June 1987
5 August 1987
22 March 1988
14 March 1989
27 March 1989
14 November 1989
28 November 1989
19 December 1989
.
EPA Press Release announcing the ROD for the Second
Operable Unit (Capping).
Lener from John Gallagher, EPA Region I, to Ethel M. Halsey,
Nasonville Water District. concerning future public meetings.
Meeting of EPA, RIDEM, and Nasonville Water District.
EPA Press Release announcing the allocation of $150,000 for
the design of a public water supply for homes near the Site.
EPA public meeting with the Nasonville Water District to
discuss the public water supply.
EPA Press Release announcing Consent Decree entered into
with approximately 51 PRPs (a $5.8 million settlement for the
Western Sand & Gravel cleanup), and Public Meeting to be
held 12115/86 to discuss agreement.
Hunt (PRP) Press Release announcing Consent Decree.
EPA public meeting with North Smithfield Town Council to
discuss the settlement for the Site.
EPA Press Release announcing finalization of EPA contract
with State of RI for funding water supply installation and
operation & maintenance.
EPA Press Release announcing the finalization of the cleanup
settlement.
EPA Press Release announcing the start of cap construction at
the Site.
EPA public meeting with the Nasonville Water District to
discuss the public water supply.
EPA public meeting with the Nasonville Water District to
discuss the public water supply.
EPA public meeting with the Nasonville Water District to
cflSCUSS the public water supply.
EPA Press Release announcing the 28 November meeting to
discuss construction of the new water supply to serve homes
affected by Site COntamination.
EPA public meeting to discuss the commencement of
construction of the new water supply.
U.S. Army Corps of Engineers (USACE) Press Release
-------
19 March 1990
19 ApriU990
21 June 1990
25 October 1990
November 1990
November 1990
4 February 1991
4 February 1991
11 February 1991
12 February 1991 -
13 March 1991
28 February 1991
15 Apri/1991
USACE Press Release discussing water tank/pumping station
construction start.
EPA/USACE Press Release announcing the start of and the
schedule for construction of the new water supply.
EP A conducts community interviews to gather information for
the preparation of this Community Relations Plan.
EPA establishes Administrative Record at two information
repositories at the Burrillville Town Hall and the EPA Records
Center (see APPENDIX B for the addresses and hours of
operation of the repositories).
EPA completes Community Relations Plan.
EPA Fact Sheet on results of Groundwater RI and RI
Addendum.
EPA Advertisement of Proposed Plan and Public Comment
Period published.
EPA Proposed Plan published.
EPA Public Meeting on Proposed Plan, Groundwater Feasibility
Study, and Feasibility Study Addendum.
EPA Public Comment Period.
EPA Informal Public Hearing on Proposed Plan, Groundwater
Feasibility Study, and Feasibility Study Addendum.
EPA Responsiveness Summary for Record of Decision on
-------
.. -
Attachment B
-------
.
I
1 - 22
UNITED STATES OF AMERICA
2 .
ENVIRONMENTAL PROTECTION AGENCY
3
REGION ONE
4
5 In the Matter of:
6 INFORMAL PUBLIC HEARING RE:
WESTERN SAND & GRAVEL SUPERFUND SITE
7
8
9
10
Burrillville Town Hall
Harrisville, Rhode Island
11
Thursday
February 28, 1991
12
13
14
The above entitled matter came on for hearing,
15 pursuant to Notice at 7:05 p.m.
16
17 BEFORE:
RICHARD C. BOYNTON, Chief
Rhode Island Superfund Section
U.S. Environmental Protection Agency
Region One
JFK Federal Building
Boston, Massachusetts 02203
18
19
20
LYNNE FRATUS
Remedial Project Manager
and
SUSAN FRANK
Community Relations Coordinator
Office of Public Affairs
U.S. Environmental Protection Agency
Region One
JFK Federal Building
Boston, Massachusetts 02203
21
22
23
24
25
APEX REPORTING
Registered Professional Reporters
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18
19
20
21
22
23
24
25
..
2
.
l_tL~L~_.t
~Eg~I~~J;B
3
Ri chard Bc,ynt.:.n
4
Lvnne Fratus
5
Warren Angell
6
Ett"lel Ha I sey
7
8
9
10
11
12
13
14
15
16
17
APEX REPORTING
~Registered Professional Reporters
(617:) 426 -3077
~ .
E~@g
......
,':t
5
1:2
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..
E_B_Q_~-£_g_Q_l_~_~-~
2
(7:05 pm)
3
.
MR. BOYNTON:
My name is Richard
Boynton.
I'm
4
Chief of the Rhode Island Superfund Section of EPA's Region I
5
I have supervisory responsibilities
for yesponse
Office.
6
actions at Superfund Sites in Rhode Island.
7
Tonight we're here to conduct an
informal publi~
8
hearing to accept oral comments on the cleanup alternatives
9
consideration for the Western Sand ~ Gravel Site.
under
10
I will serve as the Hearing Officer and, also, on
11
the hearing panel are Lynne Fratus, and I'd like to introduce
.
12
Warren Angell, who is the State Project Officer,
in the
front
13
row~ and in the rear,
from our Office of Public Affairs is
14
She's our Community Relations Coordinator.
Susan Frank.
15
We held a meeting in this building on Monday
16
the 11th,
in
this room.
to present ;~fcY~2~ion abo0t
evening,
17
the evaluational alternatives for the cleanup of the site and
18
the preferred alternative for the cleanup of the site.
The
19
public comment period began on the ne~t day,
February 12th,
20
and will close on March 13th.
21
Now,
I'd like to go over the hearing format for
~
We'll begin with a brief presentation by Lynne Fratus,
you.
23
She'll describe the proposed cleanup plan.
on my right.
24
Following Lynne's presentation, we'll ~ccept oral comments Y0U
25
wish -- may wish to make for the record.
The panel may ask
APEX REPORTING
Registered Professional Reporters
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2 .'
you some questions to -- in order to clarify your
c,:.mments.
j".
I.
I
I
We wi 11 prepare a w'r i tten resp.:.nse t.:. the c, .mment:<= I
: ,-- I
received tonight, and include the written responses with EPA'~ I
I
4
1 i iial decisic.n.
After all
5
the comments have been heard,
I
will close the hearing.
6
11 y.:.I.1 wi sh t.:. sl.lbmi t wr i t ten
c,:.mments.
yo:,'.! ma y
7
submit them to us tonight or mail them -- mail them
t h r 0:' !J 9 h
8
Met.rch 13t~l,
to Lynne, at the address on page three 01 the
9
p'r.:.p.:.sed plan.
Copies of the plan are available in the back
10
.:,1 the
rc.c.m, if
Y':''-I need t t,em.
11
12
At the conclusion of the hearing, we'll stay.for a
short time to address questions you may have about
c 1 eanl~tp
13
alternatives and the decision making process.
14
15
Those wishing to make comments tonight
s h ':' u 1 d h .:\ '.' e
filled out an index card available at the rear 01 the room.
16
If v,:.u
wish to speak and
have not completed a
card,
pleCl.se,
17
complete a card and Susan will give it to me.
I' 11
call
18
I pe061e in the order that the index cards were completed.
19
When we do call your name,
you should come forward
20
to the microphone or -- I think our
-- if our court reporter
21
can hear you clearly,
I don't think the microphone would be
22
23
necessary, but we are making a record of the proceeding.
8,:,
24
I'd like to have you come forward and qive your name and
affiliation so that we get the correct information.
25
A transcript of tonight's hearing will be prepared
APEX REPORTING
Registered Professional Reporters
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.
\
I
I
1
.and mage available as the administrative rec,:,yd here in the
2
Burrillville Town Building, and,
also, at EPA -- the EPA
3
at 90 Canal Street, Boston, Mass.
Recc,rd Center,
4
As I mentioned, we will preoare a response
t,:, .:.r a 1
5
comments received during the comment period, and
and written
6
we'll include the response~ in the responsive
summarv, o..,.ith
7
the re c,:,rd ,:,f
de c i si.:.n.
8
Lynne will
give an overview of the preferred
N.:......,
9
alternative.
10
(PaL,se. ..,
11
MS. FRATUS:
Like Dick said,
I'm going to give a
12
.
brief overview of what our preferred alternative was in the
13
as well
as the other alternatives that were
pr.:.p.:.sed plan.
14
evaluated during the feasibility study.
15
Our oreferred alternative has three major
16
The first component is called Natural Attenuati0~
c,:.mp.:,nent s.
17
with Contingent Groundwater Treatment.
18
Natural attenuation -- under natural attenuation.
19
the EPA would rely on natural processes such as biodegradation
20
chemical reactions and dilution to restorE the
and natural
21
groundwater to cleanup standards.
22
Natural attenuation has been going on historically
2J
already with the groundwater contamination since the waste was
24
deposited at the site and has been effective in reducing the
25
levels of contaminants in the groundwater historically.
APEX REPORTING
Registered Professional Reporters
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If the groundwater does nc~
I
I
I
,
I 0
process to restore the I
.
2
y~~t~~~ ltself at a
rate that's acceptable to EPA under natural attenuation. the
3 0"
EPA would utilize an active restoration
4
groundwater to cleanup standards.
5
The second
component of our preferred alternative
6
is Access Restrictions.
Due to the
current or the future
7
potential risk to public health, EPA would
propOse
8
restrictions on the use of the groundwater that poses that
9
unacceptable risk to public health.
10
The third component is Site Monitoring.
I ' I I
11
explain a little c~t more about the Access Restrictions and
12
the Site Monitoring in just a minute.
13
In discussing the first component,
I -- I st~ted
14
that EPA would utilize active restoration if the
ground~ater
15
was not restoring itself at a rate that was acceptable to EP~.
16
I'd just
like to take a moment to explain what I mean bv
that.
17
EPA utilized two methods for predicting the
18
estimated time to reach cleanup standards.
The first method
19
was utilizing hydrogeologic models.
The models were basically
20
computer programs which can input site specific perimeters
21
such as the contaminants and concentrations and the types 01
~
50i15 present.
The model will basically calculate or si~ulate
23
how the groundwater is going to behave.
24
According to hydrogeologic models,
it was
25
predicted that it would take approximately 24 to 28 years to
APEX REPORTING
Registered Professional Reporters
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."
restore the groundwater to cleanup standards.
2 .'
The second method that EPA utilized
t .:. p r .:' j E' C t t :-. ...~
..
3
cleanup times was we did a statistical
ana lysis ,:.f
the C\ c t 1).:0. 1
4
data that's been collected at the site to date.
G ... .:. u n d '.J C\ t e (
5
samoling has been going on pretty consistently
since 1'?88.
,- -
.~:.I_'
6
we had Quite a bit of data to t~ke a look at.
.'
7
AccordinQ to the analysis ~~~t
:..;;; d...d ~ we
8
deteymi ned .that it w':'lIl d take appr.:.:-:ima te I y 8
t.:. 18 years t,:,
9
restore the groundwater according to natural attenuation.
10
if the grollndwatey continlles to yes tore itself at the
That
is,
11
-
rate that it currently appears to -- it currently appears to
12
be restoring right
n.:.w,
if we pr.:.jected
that ,:.ut,
i t '...11:'1.11 d
13
take about 8 to 18 years to reach dYinking water standards.
14
According to groundwater models,
it would take approximately
15
11 to 17 years using an active restoration process.
16
The other two components of our preferred
17
alternative, which I've mentioned,
first, is Access
18
Once again, as I stated,
the access
Restrictic.ns.
19
restrictions are necessary to reduce the risk to public
20
Access restrictions would be imposed in this arEa
health.
21
delineated by this heavy -- heavy line.
22
Basically, there are four properties that would be
23
impacted by our acces~'re~trictions.
Each pr.:.perty
is
24
delineated by a different
cCllc.r.
First property is actually
25
the Western Sand & Gravel property, itself.
Then there is
APEX REPORTING
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1
2
)his yellow shaded property right here,
property, and the blue shaded property.
the green shaded
3
The third major component of EPA~s preferred
4
alternative is Site Monitoring.
The groundwater would be
5
sampled every three months, until
it's rest,:.red t.:.
c lean'.lp
6
standards.
Every three years EPA would conduct
an e val u a -: i. -:' r"o
7
of the data and determine whether
or not it's restoring it~s
8
rate -- itself at a rate that's predicted by the model or
9
faster.
10
If this did not happen -- and we would repeat this
11
every three years for the first nine years and every five
12
years thereafter.
13
If at any point in the process during one
,:,f t he.;"e=- ,
14
evaluations EPA determined that it
'.'; a c: :'-~ -:1 t
~e~toring itself ~.~
15
a rate predicted by the model or faster, EPA would implement
16
an active restoration process to meet the drinking
wate"(
17
standards.
In a minute I'll give you a brief description of
18
what the active restoration process would entail.
19
The last component or potential component
,:,f ,:,u r
20
remedy is Surface Water and Sediment Sampling.
At this point,
21
it 15 not a -- planned in the remedy but there is some future
22
sampling of the surface waters and sediments planned.
<'3
Based on the results of that monitoring, EPA would
24
determine whether or not our preferred alternative should
a 1 51:1
25
include long term monitoring of the surface water and
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1
sediments of the sit~.
2
I'd just like to give you a brief descriptiGn
NCtw,
3
of the active restoration process.
Okay,
first,
the
4
groundwater would be extracted using extraction wells.
T~le
5
groundwater would be pumped into a settling tank where
me+:al::.
6
and other solids would be collected and settled
,:,1.\ t.
T~,':'SE'
7
metals and solids would be -- wOl.\ld be disposed of at a
8
licensed facility capable of accepting such waste.
9
From the settling tank the groundwater would be
10
for further removal of metals and solids.
pumped int,:, a filter
11
the groundwater would pass
- .
After passing through the filter,
12
The air
into what we identify -- we call it an air stripper.
13
stripoer would remove the volatile organic
compounds w~ic~ afe
14
contaminants at the site.
principal
15
the way an air stripper works is that
Basically,
16
is passed in the opposite direction to the air
the grl:rI.mdwater
17
which is forced against it, and just by the nature of the
18
contaminants that tend to volitize they transfer from the
19
water into the ~ir.
20
The air is then treated using a vapor phase carbon
21
absorber prior to discharging it into the atmosphere and any
22
contaminants that were pulled out of the water are then
23
transferred onto the carbon in the -- in the carbon absorber.
24
The water that passes to the bottom of the
25
stripper is then pumped also into a liquid phase carbon
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abs~rber to remove any metals and semi-volatile
c,:.mp':,ur.ds.
3
...Finally, the water is pumped intc, a st.:.rage tank and
eventually clean water would be discharged to the Tarkiln
4
Br,:,,:,k.
5
6
The -- both the carbon and the -- the liquid
r.. h a ::. E" .'
carbon absorber and the vapor carbon absorber
w.:, 1.1 1 d t".a ve
t.:, bE I
7
changed periodically.
8
The last thing I'd like to go
c,ver
is a brief
9
,:,verv iew .:,f
what all the alternatives are that ~PA considered
10
du~ing th~ feasibility study.
There were six alternatives
11
that were evaluated during the detail analysis in the
12
feasibility study.
13
14
The first alternative is similar to the pref~rYe~
alternative.
It relies .:.n nat',,"'-al attenl.latic,n t.:, rest';'r"e tr
15
gr':'l..tndwa ter.
However, unlike the preferred alternative,
t t,e).-.;:;
16
would be no access restriction or
controls placed on the
17
pr.:.perties.
The first alternative, also, includes qroundwate~
18
mc,ni tc,r ing.
19
The second alternative is similar to the first and
20
the preferred alternative.
It, a Is,:. ,
includes access
21
restrictions.
One difference between the second alternative
22
and EPA's preferred alternative is that the access
23
24
restrictions would have been imposed in an area much larger
than that identified in EPA's preferred alternative.
25
Alternative three includes restoration of the
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1 .
gY-1:'l.U1dwater by natural attenuatil:.n.
Rather than access
2
}';estri~ticlns, this alternatille w,:,uld use what we call loIell
3
head treatment to treat future loIells that would be installed
4
in the area that poses a risk.
These well head treatment
5
systems are similar to what's currently being used in the
6
residential
tll:lmes nea r
the site.
A I 51:' ,
the third alternatillE
7
includes Qroundwater monitoring.
8
The fourth alternative restores the groundwater
9
using active restoration.
The active restoration process in
10
the fourth alternatille is identical to the one that
I just
11
.
described to you lor the preferred alternative.
12
The difference is that under alternative
f':".Ir
13
.
M.:,ni t.:,'( ing
active restoration would be started immediately.
14
would be conducted, but it loIould not be such that
we 101':' '_l1 d
15
wait for a certain period of time before we triggered the
16
restoration process.
active
17
Fo:,r alternative
f':'I.lr, fc,r
the controls on the
18
both access restrictions or well head treatment loIas
pr.:.p.er ty,
19 .
identified as being potential mechanisms to prevent or to
20
reduce the risk to public health.
Like I said it, also,
21
includes groundwater monitoring.
22
The last alternative -- I'm sorry, the fifth
23
alternative utilizes active restoration,
as we 11.
The
24
difference between the fifth alternative and the fourth
25
alternative is that the fifth alternative would discharge a
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2
pctr.tie.n e.f the gr':''-Indwate.,.o that's extracted back int,:. tl",e
i
I
I
I
. .i
, -I
"groun~water after it has been treated.
3
It's -~ it's predict~d that
the groundwater would
4
5
not all be able to be discharged back into the groundwater.
The system wouldn't be able -- were -- the
c,:,nc 1 usi.:.n
~,,< t""tl,
I
6
the groundwatar svst~m ~ay .not
be able to simulate or
7
8
assimilate the actual -- the total discharge that would be
e~t;tracted.
S,:, a
p,:.r t ic.n ,:.f
the extracted groundwater would.
9
also, have to be discharged into Tarkiln
B"",:,,:,k.
5,:, this
10
11
alternative actually has two discharges.
The controls are similar to alternative
f ,:.IJ r ,
12
13
either access restrictions or well head treatment and,
a I!:.,:,.
groundwater monitoring.
14
The last alternative, alternative
\
si); ,
is the
~ /
15
16
preferred alternative, which I just described in detail.
17
I guess that concludes my presentation.
MR. BOYNTON:
Thanks, Lynne.
18
19
We'll begin the oral comments with a statement by
20
the Rhode Island Department of Environmental Management.
Warren Angell will give that statement.
21
MR. ANGELL:
Good evening.
22
23
As Dick mentioned, my name is Warren Angell, and
24
I'm a principal engineer with the Division of Air and
Hazardous Materials, within the DEM.
25
MS. FRATUS:
Warren,
could you ,just get a little
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c;l c.se I" t.:. the mike?
2
MR. ANGELl.: Sure. I'd rather 1ace the c<,udience
3
t h,:,..\ g h.
4
MS. FRATUS: Yes. Can YCll\ turn the mike ar,:,und?
5
MR. ANGELL: It's kind ,:.1 taped d.:.wn.
6
(Pause.)
7
MR. ANGEL.L: Okay. Based '.lpCI n tt.e i n 1 ':1)" mat i I:' n
8
available at this time, the Department cd Env i y.:.nmenta I
9
Management does not concur with the remedies proposed by the
10
EPA.
11
The Department 01 Personnel have conducted a-
12
t t,.:. '( ':"-19h
review 01 the technical documents generated as a
13
result 01 this groundwater remedial investigation and
14
feasibility study.
This includes three drafts of the IRA and
15
two drafts 01 the FS generated by Olin'~ contract with BCM, as
16
well as the addenda 101" the RI and FS produced by the EPA.
17
As a result 01 this review, we have generated
18
numer.:.us
technical dc.c
-- comments and have some significant
19
concerns with both the material presented and the conclusions
20
drawn.
21
We are providing a written comment letter to the
22
EPA during this comment period that includes all 01 OUy
23
concerns in more detail.
I will only outline a 1ew of our
24
main concerns this evening.
25
First,
I would like to say tha~ the Department 01
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2
Personnel concluded that the investigation of contamination
3
,TarkilD Brook and Slatersville Reservoir was inadequate.
Tt"t i::
4
resulted in inconclusive findings regarding
~:u:' ten t ,i a 1 and
environmental and public health risks.
5
The Department will
be requesting that the
6
7
responsible parties conduct,additional sampling and adh2re~ to
8
guidelines specified by the Oepartment~
Secondly, both the OEM and the EPA
t", a v e c ':t n r:: 1 IJ d E' j
9
that the investigation of contamination to
the bedrock aquifer
10
wa 5. a 1 ::..:.
i nCt:.nc 1 usi ve.
As noted by the EPA in the proposed
11
plan, they will notify Olin that additional
stl.1dies are
12
necessary.
13
Although the OEM would like to see an exoedited
14
remedy chosen for the site, we believe that such
15
investigations should be conducted prior to selectinq a
16
remedy. thereby, allowing for a complete,
accurate, ,,,,nd
17
comprehensive selection process.
18
T t", i r d I y ,
the department
has raised numerous
19 .
c.:.ncerns
regarding the validity of the model employed by Olin
20
to characterize groundwater at the site.
As many .:.1 these
21
concerns have not yet been addressed,
we q'.testic.n tl",e
22
23
remediation scenarios and remediation ti~e~ qenerated by this
model.
We are requesting that the EPA revisit
,:.ur c,:.mments .:'"
24
the model prior to the final remedy selection.
25
Fourth, based upon groundwater classification 10r
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1
I
15
. 1
this area as designated by the Department~s Groundwater
2
.-
-Section, we believe that a natural attenuation remedy is
3
unacceptable.
-
4
The State Groundwater Protection Act mandates a
5
strong policy of
restoration and nondegradation.
Fa i 1'.1 -roo? t I:.
6
implement active restoration is in conflict with the Act and
7
is inconsistent with
the p.:.licies c'=-,nsistP.ntly applied by H,i.?
8
Groundwater Section.
9
Lastly, although we feel an active
res t.:.r a t i.:,n
10
scheme should be implemented, ~e would believe that the
11
decision mechanisms that could possibly trigger an active
12
restc.rati.:.n
scenari.:"
if natural attenuation is the
ct-.,:.sen
13
remedy, are extremely vague.
14
We are, therefore,
requesting that the EPA outline
15
in detail
the criteria that would trigge~ active restoration.
16
This mltst address b,:.th grc".lndwater and 5urif.r:-.ce water tr i r';H]£.=!(S..
17
The Dep.artment is, al.so, cc.ncerned that the
18
proposed temporary access restrictions may not prevent all
19
future development that maybe impacted by ~.~ntaminant5
fr,:,m
20
the site.
21
That ec.ne 1 udes what we ~(c.nsider tc. be our maj,:.r
22
concerns at this time.
As I have prev i.:.IJs.l y said, we're 9,:.i ng
23
to submit a more det.iled cc.mment lriter, '.within the c.:.mment
24
period, and this letter will be forwarded to the local
25
representatives and, also, entered into the administrative
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2
Thank y':".I.
3
MR. BOYNTON:
Thanks, Warren.
4
5
I'd now like to call Ethel Halsey.
MS. HALSEY:
This may well be a first.
I t ~, i "k I
6
agree with DEM tonight.
It's probably the first
time
ir-, 12
7
years.
8
9
I have some written comments which I will submit,
but I w,:,uld
like to just give a brief summary of the written
10
ccomments.
11
.
I be:~eve that the plan, as outlined by EPA,
is an
12
13
insult to the intelligence of the people of the effected area.
14
Anyo:one wh,:, has taken ttle .:.pp.:ortunity tCI read and study tt'e
15
plan realizes that the chances of their being any real
~
c 1 ea'
taking place under that plan are minuscule.
16
We weren't fooled by the former
cleanup plans
17
presented by EPA.
When they told us they were going
t c, b u i 1 d
18
a cap of plastic and clay and sand and cover it over
wi tt,
19
20
grass and call it a cleanup, we knew that was not a cleanup.
21
That was literally and figuratively a coverup.
22
When they said they were going to build us a water
23
supply, we said, wonderful; we certainly need water, and if we
24
ever get it, we can celebrate, but it is not a cleanup.
25
As I see it, the benefactors -- the big
benefactors of alternative six, as outlined tonight, will be
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~h~ owners of Western Sand ~ Gravel,
the owners of Landfill
2
.' and R~sour ce Recclvery, whcl happen tc. be the same as t~Je
c.wners
3
of DC Land Company~ and they, also, happen to own the
4
so-called Burma Road, which passes adjacent to the site.
5
These are the properties that EPA is talking
a b'::/j t
6
purchasing from the present owners,
to limit access to the
7
area.
8
Now, on the matter of natural
at tenua t io:.n,
9
attenuation in my dictionary means dilution or weakening.
As
10
I understand it, the main force that wiJl
cause this
11
attenuation to occur naturally -- that's what we're talk~ng
12
about natural attenuation -- is rain water.
13
Now, three or four years ago we sat in this
r ':":' tTI
14
and EPA presented us a plan that they were going to build a
15
Cdp -- an impermeable cap over the waste so that the rain
16
water could not get to it.
NC1w,
they are telling us that the
17
rain water is going to cause the natural attenuation of the
18
waste.
I'm a little confused.
19
My recommendation,
for what it's worth,
is that
20
we've had enough studies; we've had enough monitoring;
we've
21
hAd enough records of decision and all the rest of the
22
gObble-glob.
We need action and we need it now.
23
.We need the wa~te water -- the groundwater
24
treatment plant should be built immediately.
It should have
25
been built ten years ago, when it was first proposed by the
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'.... .
23
.
1
I
"State.
It would have been a lot
e.::\sier
and a lot cheaper,
2
because the wastes would have been in a more concentrated
3
area.
Now they are ~ll spread out allover the place.
f,j.:.
4
IJ,:.nder
it is going to take 18 years.
5
The State said that they
c.:,uld d,:, it
in one.
~
, ,
6
t,:..:r,
qlJestic.n that,
but ma',>,'be
t w.:. ':11"
1;,hree,
and by t~li!::, tim.;:-,
7
it would have been done.
8
I dc. n,:.t think
the r e ':' u q ~I t
t,:. be a buy ,:,ut
':' of the
9
surrounding areas.
I think the policy that should be
10
instituted should be let the buyer beware and nobody who
11
blJilds
f'("':'1TI n.:.w ,:,n
in that area should be allowed to
h,:..:.k
int,:,
12
the -- to tie into the Nasonville water supply.
The r e sot,,:, u 1 d
13
be no well head treatment for the same
-- f,:,r the s,",me
.,.-ea~.I'"
14
In c.:,nc 1 usi,:'n,
just let me read my
c ':. n c Iud i n q
15
cI:.mments
from my written comments.
"We've r-,ad
enc,ugh st'_tdie':;:-.
16
rep,:.r t s,
RI's, ROD's, FS's, and (
-,er paper plJ~,h i ~',Ci
.-,,:: t i ine
17
wasting pro.jects.
Get the stuff out of there and get it out
18
n':tw. II
19
MR. BOYNTON:
Thank yelu.
20
(Pause. )
21
MR. BOYNTON:
Is there anyone else that would like
22
to make a comment for the record?
(Pause.)
24
MR. BOYNTON:
If there are no further comments for
25
the rece.rd,
I' 11
close the hearing.
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1°.
..
We'll
remain for a short time for
ql.lesti.:.ns and
2
.informal discussions about the remedy and the procedures.
3
(Pause.)
4
This hearing is now closed.
MR. BOYNTON:
5
(Whereupon, on February 28th,
1990, at 7:30 pm,
6
the hearing in the above entitled matter was closed.)
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
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20
. 1
CERTIFICATE OF REPORTER AND TRANSCRIBER
2 "
3
before: RICHARD BOYNTON. Environmental Protection Aqency
4 .
1n the Matter of:
This is to certify that the attached proceedings
5
6
INFORMAL PUBLIC HEARING
WESTERN SAND & GRAVEL SITE
7
8
9 Place:
Harrisville, Rhode Island
10 Date:
February 28, 1991
12
accurate and complete transcript prepared from the notes
11
were held as herein appears, and that this is the true, .
13
and/or recordings taken
of the above entitled proceeding.
14
15
16 Donna Br ideau
Reporter & Transcriber
03/04/91
Date
17
18
19
20
21
22
23
24
25
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APPENDIX D
RECORD OF DECISION
WESTERN SAND , GRAVEL SITE
,"' BXAMPLE 01' EVALUATION OF NATURAL ATTENUATION
. BENZENE
I.
Introduction
The evaluation of natural attenuation shall be conducted on each
of the four indicator compounds. The evaluation has three major
steps:
1)
Tabulate the data and calculate the sum of the maximum
concentrations detected in each well 'cluster;
Calculate the theoretical concentrations; and,
2)
3)
Conduct a nonparametric statistical rank test to
evaluate how well the actual data compares to the
theoretical data.
Below is an example of the evaluation for benzene.
II.
Tabulate the data and calculate the sum of the maximum
concentrations detected in each well cluster
The first step in the evaluation consists of tabulating the
actual data collected for the site. The data from the following
well clusters must be utilized in the evaluation: C2, C3, C4, C5,
C6, 12, 13, 16, and 11-3. Below is a table of the actual data
collected for benzene during the Remedial Investigation. Please
note that the data from the RI was utilized for the example only
and shall not be utilized in future evaluations. The table
should identify the maximum concentration in each well cluster
during each sampling round. In addition, the table should also
identify the sum of the maximum concentrations for each sampling
round. Finally, the table should identify the elapsed time in
months. Due to the proximity of well clusters C5 and 113, the
sum of the maximum concentrations detected shall be determined
from using either the maximum from C5 or the maximum from 113,
-------
.
Tabulation of Actual Data for Benzene.
Maximum Concentrations Detected in Well Cluster
Well May Sept Dee Feb Sept Aug Nov
Cluster 1988.' J..2.ll 1988 1989 1989 1990 1990
C2 3
C3
C4 27 12 3 4 2 1 5
C5 42 35 36 34 1 4
C6
12
13 5 3 5 2 1 1 2
16
113 14 16 13 19
Actual
Sum of
Maximum 74 50 24 42 37 18 26
Cone.
Total
No. of 0 4 7 9 16 27 30
Months
III. Calculate the theoretical concentrations
The theoretical concentrations shall be determined from the
equations presented in the ROD for each of the four indicator
compounds. These equations were developed from the results of
three hydrogeologic models, MODFLOW, STLINE and the EPA Batch
Flushing Model. The following equation was developed by EPA to
predict the theoretical concentrations for benzene:
Benzene:
y = antilog (1.359 - 0.015(x»
where
x = number of months after the ROD signing (i.e.
x = 1 for April 1991, x = 2 for May 1991,
etc. )
y = theoretical concentrations of contaminant
(ppb)
The equation presented above for.benzene is based on data
collected after the ROD signing. Since this example utilizes
data collected prior to the ROD signing, EPA had to adjust the
equation. The adjusted equation to be utilized for this example
only. is:
Benzene:
y =
antilog (1.869 - O.015(x»
To calculate the predicted theoretical concentrations, insert the
-------
.
Tabulation of Theoretical Data for Benzene
-,tal
. of 0 .- 4 7 9 16 27 30
Months
Theoretical
Sum of
Maximum 74 64 58 54 43 29 26
Cone.
IV.
Conduct a nonparametric statistical rank test to evaluate
how well the actual data compares to the theoretical data.
A statistical comparison of the actual data to the theoretical
data shall be conducted using the nonparametric distribution free
signed rank test of Wilcoxon with a 95 percent significance level
as described in NonDarametric statistical Methods (by Hollander.
and Wolfe, published by John Wiley in 1973, on pages 26-38). In
summary, the rank test determines whether the trend established
by actual data falls below the trend established by the .
theoretical data. If the trend for the actual data does not fal~
below the trend for the theoretical data as determined by the
rank test, active restoration shall be implemented. All
compounds must pass the rank test. If one compound fails the
rank test then active restoration shall be implemented.
The rank test has six steps. These six steps are summarized
below followed by the actual results for the rank test.
step 1:
Compute the difference between the actual and
theoretical data as follows:
Yi = Co - C~
where Co
=
the actual sum of the maximum
concentrations determined in section II
above.
C~
=
the theoretical sum of the maximum
concentrations determined in section III
above.
Yi
=
the difference between the actual and
the theoretical.
step 2:
Rank the absolute value of the difference as follows:
-------
step 3:
Determine W. as follows:
1
Set. Wi = 1 if Yi > 0
,.'Set W~ = 0 if Yi ~ 0
Step 4:-
Compute T. as follows:
1
Ti = E Ri X Wi
step 5
Compute Tr as follows:
Tr = [n(n+1)/2] - t(C(,n)
where n
0<
= the number of samples
= 0.055 (95% significance)
NOTE: t(C(,n) is determined from the attached tables
which are found in the reference discussed above.
step 6:
Determine in active restoration should be implemented
as follows:
If Ti ~
If Ti >
Tr do not implement active restoration
Tr implement active restoration
Results of Rank Test for Benzene
Co Ct Y. Iy I R. W. ~ R.xW.
1 I il 1 1 1 1
74 74 0 0 1 0 0
50 64 -14 14 6 0 0
24, 58. -34 34 7 0 0
42 54 -12 12 5 0 0
37 43 -6 6 3 0 0
18 29 -11 11 4 0 0
26 26 0 0 2 0 0
Ti= 0
Tr = [7(7+1)/2] - t(7,0.055)
= 28 - 24* = 4
* From attached table.
Since Ti < Tr' active restoration shall not be implemented.
This exercise must also be conducted for the three remaining
indicator compounds. If one compound fails the rank test, active
-------
.
..
Tllble ..t.". Upptl tllil pTobllbililies 10' tM lUlU distribution 01 WilCX'xon "
stgned 1'l1I'IK. T+ ,Ultistic: n. 3(1)15
Por Iltvcn II. the table entry ror the point JC isPo (T+ > JC). Under these con4itionl,tr JC is
IUcb thltP 0 (T+ > JC). O. \beD' (Q, II). x:.
II
:r 3 4 5 6 7 8 9
3 .625
4 .375
5 .250 .562
6 .125 .438
1 .312
8 .188 .500
9 .125 .406
10 .062 ..312
11 .'219 .500
12 .156 .422
13 .094 .344
14 .061 .281 .531
15 .031 .219 0469
16 .156 .406
17 .109 .344
18 .078 .289 .517
19 .047 .234 .473
20 .031 .188 .422
21 .016 .148 .371
22 .109 .320
23 .078 .273 .500
24 .055 .230 .455
25 .039 .191 .410
26 .023 .156 .367
2; .016 .125 .326
28 .008 .098 .285
29 .074 .248
30 .055 .213
31 .039 .180
32 .027 . .150
33 .020 .125
34 .012 .102
35 .008 .082
36 .004 .064
37 .049
38 .037
39 .027
40 .020
41 .014
42 .010
43 .006
44 .004
45 .002
169
Hollander, M. and D.A. Wolfe, 1973, Nonparametric statistical
-------
."
Tule A.4 (continued)
n
% 10 .11 12 13 14 15
28 .500
29 A61
30 .423
31 .385
32 .348
33 .312 .517
34 .278 .483
J5 . .246 ....9
36 .216 AI6
37 .188 .382
38 .161 .350
39 .138 .319 .515
40 .116 .289 .485
41 .119 7 .260 .A55
42 .080 .232 .A 25
43 .065 .207 .396
44 .053 .183 .367
45 .042 .160 .339
46 .032 .139 .311 .500
47 .024 .120 .285 .473
48 .019 .103 .259 .446
49 .0]4 .087 .235 .420
50 .0]0 .074 .212 .393
51 .007 .062 .190 .368
5:2 .005 .051 .170 .342
53 .003 .042 .151 .318 .500
S
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.
.. Ttlble A.4 (continued)
"
Jt 10 11 12 13 14 15
78 .000 .011 .059 .165
79 .009 .052 .151
80 .007 .045 .138
81 .005 .039 .126
82 .004 .034 .115
83 .003 .029 .104
84 .002 .025 .094
85 . .002 .021 .084
86 .001 .018 .076
87 .001 .015 .068
88 .001 .012 . .060
89 .000 .010 .053
90 .000 .008 .047
91 .000 .007 .042
92 .005 .036
93 .004 .032
94 .003 .028
95 .003 .024
96 .002 .021
97 .002 .018
98 .001 .015
99 .001 .013
100 .001 .011
101 .000 .009
102 .000 .008
103 .000 .006
104 .000 .005
105 .000 .004
106 .003
1(17 .003
108 .002
109 .002
no .001
1)1 .001
112 .0(\ I .;.,.
IU .001
; 14 .000
U5 .000
il6 .000
117 .000
118 .000
119 .000
120 .000
Adapted from Table C of A Norr1»'llmrmc Irrtroducriorr to Stlltilfics, by C. H. Kraft and
C. van £eden, Macmillan, Ne.' York. 1968, with the permission of the authors and the
publisba. Copyright C> 1968, by the Macmillan CompIJlY.
2il
Hollander, M. and D.A. Wolfe, 1973, Nonparametric statistical
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. .
APPEND:IX E
RECORD OF DEC:IS:ION
WESTERN SAND , GRAVEL S:ITE
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. -
:l:;T A Ti OF RHODE IS~ND AND PROVIDENCE PLANT A TIONS
~.
D.~ment ot Environmental Mllnilemlnt
O".1CI OF LEGAL SERVICES
8 Haye. Str.tt
Providence, LJ. 02808
(iOl)277.~771 ...
P1...8 note ft.w tel.phone number
401-2"-660' PAS~IMIL~ ~SSAa~
FA~tnMILE NO.
(401) 274-7337
filE CO~y ~\~
.ANY PRO!lL!:M~ PL~"'II~ ~~LL!
(401) 277-6607
Number of pegel
d-.j-
. ."
(.zclu~in; cov.r .h..t)
mH~ENT! ! I
PL~"'SE ~rLI~. !~~tA~~
To~L~
N FIRM/LOCATION
\
fn}:}.. 6 73~
TEL. NO. FAX NO.
. I ~, .fJ1.
DATE SENT: j..,t - /~ - ~ (
TIME S!NT:--Lm! h{~
COMMENTS:
~'-
(1m) . (pm) .
~a~~
Sign.d .
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4 '"JSi.1tqJ I State of Rhode Island and ProvIdence Plan-tatlons .
Department of Environmental Management.
- Office of the Director
9 Hayes Street
Provld.nce, RI ~2908 .
. .
J
,
10 April 1981
JUlie 8e18ga
Reglonal A4mlni.trator .
U.S. Environmental Protection Agency
John P. ~ennedy 'aderal BUilding.
Boaton, MA 02203-2211
RE: We.tern Sand and Crave 1 8uperfun~ Sit.
Dear M.. Belagal
~e Rhode I.land Department of Environmental Management (RIDEM) ha.
completed it. review ot the Record of Deoi.ion (ROD) and
Reepon.ivenes8 Summary for the propoaed remedy at the We.tern Sand
and Gravel Supertund Site in Burrillv111e, Rhode I.land.
In a letter dated 13 March 1981, addre..ed to Lynne Fratu., thi.
Department aubmitted our comment. on the propo..a remedy. At that
time, we intormed your agency that. we did not concur tiith the
propo.ea remedy and we cited our rationale tor that determination.
We have reviewed the Draft Record of Deci-ion and your agencY'a
re.pon.e to our comment. and thi. Department maintain. it. previou.
pO.1tion of nonconcurrence.
Listed below are the Department'. primary concern. regarding the
alcord of Dlci.ion.
1.
Department personnel have concluded that the
inve.tigation ot surtace water contamination to Tarklin
Brook an4 the Slater.ville Re.ervoir wa. inadequate.
Tbi. ha. re.ulted .in 1nconclu.1v. f1ndinC;1 1"'c;ar~in;
potential environmental and pUblic health ri8k.. The
Department. ha. reque.ted that the re.pon.ible part1ea
conduct additional aamplin; which adhere. to quid. line.
.pecitiact 8arl1*r I:»y this Department Cae. attaoh.d) I
bowever, ve have no enforoeable commitment from tbe
re.pon'.ible partie. that the appropriate ..urtace water
inve.ti,at1on. will I:»e con4ucte4. Although the remedy
AlJOW8 tor additional activities i.e aotive re.toration
and/or long term monitoring of .urtace water. and
.ediment. "1f it i. nece..ary t.o protect '1'ark11n Brook",
this Department t.el. .trongly that adct1tional .urtaoe
water and .ediment investigation. with continued
monitoring .hould be rlquttld a. part ot the ROD. The
T.Jephone40t.~77.l71', TOO 277-6800, FAX 214,7337
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2.
.
,
additional .tudie. .boule! be clearly identified in the
ROD and the re.ult. .hould be oon.idered .. part of the
0" triqgerin; .echani.. for active re.toration. With no
.".. conclu.ive evidence that Tarklin Brook i. hot being
0" advu.ely impacted and with no required future 8urface
water inve.ti9ation./monitorin; required, we ~l1eve the
ROD 1. not adequately protective of the nearby .urface
water..
8a.e4 upon groundwater cla..ification for thi. area, as
de.ignated by thi. Department'. Croundwater section, we
believe that a natural attenuation reaeely i.
unacoeptable. The State Groundwater Protection Act
mandata. & .tron9 policy ot re~toration and non-
da;radation. Failure to impl..ent activ. re.toration i.
in conflict with the Aot and 1. inoon.i.tent with the
polioie. con.iatently applied by ~e Groundwater Seotion
(lea attached). Although in a letter trom Marrill Hohman
on 27 )larch 1991 the !Pl." poaition re;ardin; State DAR.
1. explained, "e do not aqrae.witb hi. a..e...ent ot the
Department'. enrorce~ent capabilities related to
;roundwater. We al.o do not believe that allowin; tor
a twenty-tour year cleanup via natural attenuation verau.
an eleven y.ar cleanup uain; an activ. re.toration
machani.m 1. protective ot human health and the
envi~onmant. .
A. mentioned above, the Department prefer. an active
re.toration alternative. In addition, we believe the
de.cribed 4eci.ion mechani.m that could potentially
trigger an active re.toration 8cenario .hould includa not
only the .onitoring information trom the overburden
aquifer but additional bedrock aquiter data and .urfaca
water data. We are a1.0 concerned that tha tr1g;ering
machani.m it.elf ..y not be .ufficiently .enaitive to
.i;nificant data fluctuation. and, theretore, may not ba
a4equately proteotive. .
'!'h. Department i. &1'0 concerne4 that the propo.ed
~emporary 80C... re.trictiona may not etfectively protect
.811 groundwatar u.er. in the area. specificallY, we are
concerned that future development o,f .i;nificant
commercial or re.idential/municipal ;roundwater u.era
out.ide of the area de.i9nate4 for aooe.. re.triction .ay
alter contaminant migration from ~e .ite an4 could
potentially impact unprotected area..
Without adequate information concern in; the bedrock aquiter
contamination, potential impact. to .urface watera and adequate
in.t1tutional control. enforoed and in plaoe, thi. Department teal.
the .elaction of a remedy for this sit. at thil t1.. i.'premature.
MY .tatt ha. generated other technical comment. re~ardin; .pacific
item. in tha ROD and in the Re.pon.ivana.. Summary. 'rha.e comment.
are attached.
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.
I urge you to .trongly oonsider our concern. prior to finalizing
your aecord of Deci.ion for thi. .ite. Thi. Department would be
willing -'to- d1..O\1.. any of th..e 188U.. with you in hope. of
re.olv~9 the d1fterence. our .gencie. currently have.
,.-
Very truly your.,
f:i:. Dvr~
Director
LD/kz
cc: Jame. W. "..ter, Thoma. D. Get., Xerrill: Hobman
u/8/w.qrod2
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SENT BY:Xerox Telecopier ~020 ; 4-'~-&' ;'~:i,~~ ;
Au)"",,,,
,. .
.
, '
RECORD OF DECISION
..'
1M foU()~ ",., Ihb /JepQttmenl:r outIttJlldbw ~ncmu tmd ~ IU they relate to
&cord oj D«:J.rion: '.
General Comments:
. .
The BP A baa stated in the ROD that after evalUating the bedrock lDvestiptioD they will
determine if it Is necessary to modify the seleeted remedy to- include active restoration.
. Reaidcnual bedro~ wella m the area are mown to be contJtmfnAted. The source of the
residential bedrock wella contamination was not confirmed IS the integrity of the existing
bedrock wells was questioned. Currently, data collected from the proposed bedrock wells
will Dot be included in the decision mechAn~lm for active restoration. Comiderinl the
disttibutioDi of CODtAmfnA"ts at the lite, the tationa.1e for the additioDal bedrock
investiaation, and the nature of the bedrock investigations, the State feels that the bedrock
wella should be included in any decisions concendng the active r86toration alternative. The
State wou1d be willing to meet with the EP A to discuss possible trigger me~Ant&mS for the
bedrock wells.
Additionally, the main body of the ROD does not contain tanguaae concerning the
construction and or lOQtion of additional bedrock welll (Information conceminB the
monitoring, genera1location and construction of the proposed bedrock wells is presented
in Appendix C). Due to problems associated with the ex1stiq bedro~ wells and our
concerns reiucting the sightini of additional bedro~k weDs, we request adequate opportunity
to review and comment on any documents perte;,,;ng to the location (including location
mechanisms), construction and development of the proposed bedrock wells.
SurJace J„Qf~" tmd..hdJmmts ~
The EP A has stated that after reYiewin& additionallU1'face water and secUment data, they
wm determine if it is neceuary to modify the .elected remedy to include active restoration.
'lbe Alen")' hu 'not swed the nature of the mechanism to be used to determine if
modification of the remedy II neetssary. 1be ROD ,bould include the mechanism to be
employed to determine if modification fa required. 'lbe ROD should be modified to include
State input and approval of the triiler mechan!cs for active restoration. In addition,
tanauase should be included In the ROD which would require additionallamplina of the
stream system u a mandatory portion of the remedy.
-------
.
Specific Comments:
1. ~ale 3 (2nd paragraph): "The U.S. Army Corps of &peers has indicated that the
pe~nt ~temative water supply is certifiably complete and operational"
This statement Ihould be revised to reflect the exact ItatuJ of
the project u deseribed by the Army Corps of Ensineen in
QO%tespondence to ~e "Fratus dated 19 February 1991 from
Maurice Beaudion. It read. as follows: "The project exclUltve
of the residential connections 1nstallation and flushini of
domestic water aemcel and meten and operation and
maintenance training of the aeieCted" I)'Ste~ operator is
complete u of th!a date."
2. Peae 9 (3rd par~graph): T)'po: "Once" should be "One".
3. Page 26 (3rd parasraph): Typo: "evezy three years for the first three years" should
read as fonows: "eveI)' three years for the first nine years".
~.
4. Page 26 (4th paragraph): "Assumina that the area requiring remediation at the
time wben active restoration is begun is equal to the area delineated by the 100 pp"b
plume ~ntour. it is estimated that the groundwater shall be restored within 11 years."
Accordini to
~ of the Groundwater Feasibility Study. this remediation
time is incorrect. Said tables indicate that the remediation time
for the 1 ppb plume is and 11 years.
5. Page 36 .Commum~ Acceptance: language should be added to this section to
indicate that the residents did not support the purchase of property for access
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RESPONS~SS~Y
TM follo..w" t;I!e thl.r ~~ DUtstanding COncmIJ a1Ul c1arijicatiOlLf as they relate to the
RaponsMM.u SIDruna1)1:
.
Comm~ .{
The SPA hu Itated that they have been in dolO contact with the DBM durfna the
development of the current remedy for the lite. The BPA cites a meetiq that they had
with the DBM on 5 December 1990, In which they pre&ented their preferred alternative for
the lite. They mention that the DEM had DO aigDificant comments durlDa this meeti%1g or
to any of the submittals of the Draft FS Addendum dated Jan~ 4'1~91. January 91991
or JanulJ)' 22 1991. The EP A alao Itatel that it waa not undI .Januay 1991. that we first
indicated that we considered the Rhode Island Groundwater Protection Act to be an ARAR
mandatina active restoration.
On May 15 1990 the EP A met with State officials and presented their proposed plan for this
8lte. The preferred alternative at this time was ODe of aCtive restoration (pump and treat).
The only question presented to us at that time W8I whether they would try to capture the
100 part per billion plume or the 1 part per billion plume. Natural attenuation was Dever
mentioned at this time. It was not until the aforesaid December 5 1990 meeting, that we
were fint informed of the EP A's intent to choose a natural attenuation alternative. AI this
was a rather significant chanle in plam. we were not prepared to offer wmments at that
time. AJ mentioned. Draft FS Addendum documentS were submitted to DEM throughout
the month of January. The DBM provided c;1Ommenta to the appropriate drafts of laid
documents.
During a conference eall with the EPA. we indicated that a remedy l'.AtHna for natural
attenuation was inconsistent with the RIOW ProtectJon Act and the subsequent policies of
the program consistently enfor"d by this Department. .A copy of the relevant portions of
the RIOW Protection Act was forwarded to the EPA. In a meeting of February 26 1991,
and in correspondence dated 28 February 1991 and received 1 March 1991, the EPA
requested specific documenta.t1on to suppon our position.. 111e fmormadon requested by the
BP A required an extensive record search and was quite voluminous. AI we proceeded to
. compile information durinl the formal comment period we realized that more time would
be necessary to complete the taSk in a thorough and confident mA1'\ner. The BP A denied
our request for aD ateDifon.
CtJmmml ~
The EP A hu stated that the lelected remedy. .110\\1 for additional aamplina activities to be
conducted of the lUtface water and lec1lmen~ fr' EP A determines' that the remedy is not
pro~. of pubHc health and the environment lanIuaIe mould be included m the ROD
which would ~ additional aampUna of the stream l)'ltem u a mandatOry portion of the
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--.., -. ..w.
.
Also, the EP A has DOt represented an opinion as to whether they qree or disagree with our
commenu aDd -coDcema regarding the adequacy of the surface water u.d .ediment
. invesdaatfon. The ABmcy should have qualified personnel from their Water Resources
Section cOnduct a tJrorough review of this assessment and offer their profeasionaI COJ"ments.
CDm.m.!nt ~
The EP A has stated that based upon a m;ow of the bedrock wens !nstalled at the lite as
part of the Groundwater Remedial Investiaation Report the highly fractured zone of the
bedrock would be approximately thirty.fiv~ feet in thfckntjl, which would result in the GZ3-
2 wen being located in the hiahly fractured portion of the overburden and not in the more
competent bedrock. The BP A should ltate whether any confident conc1uaionJ concernin&
the depth of the bedrock fracture zone can be made baaed upOn two weDs. It ahould be
noted that information presented In the Geobydrologica1 and Treatment Fea.dbillty Studies
indicate the depth of the fracture bedrock zone at the lite ia not uniform. In addition
information presented in the 1981 Bedrock Water ContSlminAtion Study indicates that the
aZ-3 well screen wu not placed in the highly fractured zone of the bedrock (the well was
screened below the highly fractured zone).
The EP A has stated that additional bedrcx:k wells should be installed between the site ant!
the residential neighborhood to the west of the site. A preliminary review of the Project
Operations Plan for Additional Bedrock Investigation indicatc5 that the proposed locations
lor these wells He outside of the bi&h1y contAminated plumes. The need for additional
bedrock wells arose from questions concerning the integrity of the existing bedrock wells and
therefore whether the bedrock is contaminated. It is our understandina that the purpose
of the additional bedrock wells is to determine if contamination exists in the bedrock
aquifer. by plac:in& the wells further away from the more highly-contAmtnated area. the
likelihood of detecting contSl~iMtion is decreased.
The EP A believes that leopbysica1 techniques are not required for the sighting of these
wells. The ROD as wriuen does not require that the additional bedrock wens be fwlctional,
In that the wells do not have to be drilled into productive fractures. Considering the nature
of bedrock investilationa, the EP A should require that the additional wel1l be installed as
to maximize the probability of encountering fractures or require that if poaslble the wells
should be fuDctfow. It is the State's contention that the use of geophysical tedmfques
would optimize the lightiq of the additional bedrock we11a. In addition Beophysical
techniques may be used to addreas CODtJLmtMtlon outside of the ,ltudy area. , '
Commmt 4.
Tl1e E?A hu stated that the model employed at the lite provides a conservative estimate
ot the time necessary to restore the JI'Oundwater to cleanup levea. and that a multilayer
, model is not necessary. In addition the BP A has Imted that not enoup fnfonnation is
avaDable to calibrate a multilayer model. Durina a meetlna held on 28 lune 1990. the EP A
and the EP A's contractor agreed with tbe State concerning the inadequacies of the mode~
-------
o:IC:.11 1.1 I . "III!. WA 1111 I ~ '" W'" 4111' I W ~ W . .. - '" II I
, .6' I." 81. ,
~W,.I~'''W1
Wit --- ..... ....
.
.
extraction weUs and more realiatic active reatoration IcenariOS. The BP A. the EP A'.
contractor Ud"1he State were IUpposed to meet with the PRPa after they had reca1Ibrated
the mod~1 and iDstaDed additional layer to diacuas pouible .chemes for extraction well
locationsI' After reeelviDa a proposed .chedule from the PaPa concemina the time required
to mate the Deceua:y modifications" to the modo!. the EPA stated that the modification
schedule wu ,~~asJve and there wu no 10lller a Deed for a multJ1ayer model. 1bis
decision was made without consultinl the State or sendina the State Information from the
EP A or the EP A'I contractor which would justify the BP A decision.
To date the EP A has not Indicated how they correlated the remediation times for lone
layer model to that produced by a multilayer model. The multilayer model is not subject
to the WDe constraints IS the one layer model and has the potet1t1al to allow lor optim;~"i
atraction we111ocation. depth and pumplDa rate. The EPA has Dot indicated what
additional data would be needed for the calibration of . multilayer modeL It should be
Doted that . multilayer model was employed 111 the 1985 RIIPS. AlIo. the EP A has not .
addressed the StaM', comment concernina the apparent discrepancy between the discharae
point into the Tark1in Brook used In tbo model and the di.charse points pre,eDted in the
Remed1allDvestigation Report. If the discharae points in the RI are eorrect, (the EP A
" apparently agree with the ROD discharge pomt) theD the remediation time for natural
" attenuation may, be underestimated and the time for active reltoration may be
overestimated.
Commt!nt ~
The theoretical contAminant concentratioDS predicted by the ErA are baaed upon a model
which the State and the pubUc has Dot had the opportunity to review. Therefore the State
cannot eoDCUl with the trigcr mechanism u we have not had the opportunity to determine
the c:apabWtie& and constrainu of the EP A model.
-
Also. the BP A has stated that they could not dev~1op specific trigen for surface water and
sediment investigation since it is not known at this point what type of data will be co11ected.
'Ibis issue could be relolved if the ROD apecified that the aurface water and sediment data
Deeds. and based upon ~modified the triger mec,.."fftft
CQmmDII 1
" Access resuicdcm boundarJes should have addressed the cone of influence of supply wells
, for potential future development in the area, such as the consuuctlon of private residents,
houslq developmentS or I IIWDicipal weD aimilar to that reference In t"nmmeDt 5 of the
EPA's RespoDSivenw S"m~.
".
Cnmml!lIt 0
The EP A hu stated that lunher investlaation in the F well area is Dot Justified due to the
fact that, concentrations of cont,m;","ts found In the weD are not aJsnificant. the
-------
.
cont.Am1fttl1ion. and CODt..llm1nation was not found in the Cl well. Remedial investigation&,
(with the exce.ption of a Umited uumber of aamplina rounds) was not canied out in this F
well are~' Infonnation presented in the 1980 Geohydrologica1and Treatment Feasibility
Studiea iDdicate tPt the concentratioDi of COJ1t1m4nllnts found in the F wel1£ WII ,4m{1ar to
the ~ntamfDlJ1t observed In wells located clOler to the visible waste pita, (concentration
of ceriain contsum"Ants waa bfJher In the F weD than the wellJ located closer to the above
pits). In addition this area WII Dot subject to any remedial actions durlni the consuuction
of the cap. Finally weD C 1 fa screened in the bedrock overburden interface and is a low
permeability well.
Comm~nt 1J
The EP A bas stated that they do not understand the RIDEM'a request for the assumptions
used to generate the piezometric maps. In addition the EP A Doted that pIezometric maps
are developed by connectin& points of equal piezometric measurements. It should be noted
that the piezometric contour maps generated In the 1989 Remedial Investigation report were
limited to actual data points. The contour lines ,eDerated in the 1990 repen were computer
generated and used extrapolated lines outside of the sample area. RIDE.M'a comments
were desianed to address the above.
Commen.t 2l
The EP A has indicated that trich1oroethene was the most frequently detected compound.
Information .presented in the 1990 Groundwater Feasibility Study Indicates that
trichloroethene was n.Q1 the most frequently detected compound. other compounds were
detected at higher frequencies and at higher maximum concentrations. The most frequently
detected compound according to said document appears to be l,2-Dich1oroethene.
Also, the EP A has stated that if the non-indicator compounds do not behave in a fashion
similar to the indicator compounds then the EP A &ball modify the ROD to ensure that the
remedy is proteCtive of pubUc health and the environment. The EP A should verify that the
non-indicator compounds are currently behaving in a fashiOD simllar to that of the indicator
compounds. In order to avoid possible problems concerning EP A determination whether
non-indicator compounds are behaving in a fashion lImn", to that of the indicator
compounds, the State proposes that a series of compliance Jraphs be generated for the non.
Indicator compounds. The State would be wi11ing to assist the EP A in the above endeavor.
In additioD the EP A should specify the activation process to be employed when one of the
Don-indicator compounds exceeds the compIfance curve. One posdble mec1oJ'l'i4,ms to
address the l1onindicator compounds is to construct a trJaer curve composed of tota.1
organic compounds found at the site. 'l')ili tottJ organic compounds trigger curve would be
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617 "~ ~~~a. .."
Cnmmm1 31 .~ -
The EPA ~ ltated.Jbat the foUowiq locatioDS STRl. STR2. aDd STR3 are located
uparadient of the lite. The EP A also DQted that the concentrations of metala In STR2 and
STR3 to SUP1. STR4 and STR5 ue of the wne order of m..ptude and therefore
concluded that many of the metals may be occ:urrlni aatura11y. The 1990 PS model, (A
model which the EP A has apparently approved) has contaminants from the lite enteriq the
ltreBm In the vicinity of snu and STR3. The SPA &bould darlfy the above dlscrepaney,
(ie why they believe that sampUna station STR2 and STR3 are upgradient of the site, while
the apparently EP A approved FS model, has the discb~e points for cont.mfn~U from the
site located in the vicinity of the sampUna ltationa labeled "upgradient" by the EPA.
~
The State has completed a pre1fm.'lIuy review of the Itatistica1ly methods to be employed
in the trigger mechAnfll'n$- The State questions the use of tbe employed alpha value and
feels that an alternative alpha value such as to 0.025 or 0.01 would be more conservative
and protective of public health. The State also CtUe5UOD6 thelo&ic of using the ROD sipS
.date as the startina x value for the equations employed by the EP A. Use of the ROD-
ltanin& date produces unrealistic curves. Therefore the State proposes mat x values
col'tf1!ue from those presented in the FS Addendum.
The State also questions the mechaniama used for the Input of the triger curvet presented
in tho ROD. The State feels that the FS Addendum Theoretical Curves are more
appropriate and more protective of pubUc health than the ODes employed in the ROD.
However it should be noted that the State has still not been with provided a copy of the
EPA model employed in the triger mechanism and thua hu not had the opportUnity to
-------
:l:8TATZ OF ~D! ~ANJ) p~ PlANTlmONS
~ePartment at EnYlronmental Management
0" DMSION OF GROUNDWATER AND
: FRESHWATER WETlANDS
.. ~Ol ~ Street
PnMdmce. R.L 02Q08 - 8781
.
'1'0:
'rom Getz
Chief
DEK/Divi.ion of Air and Hazardou8 Katerial.
FROM:
Sua Xiernan ~I ~
Deputy Chief. O~
DEM/Qroundwater Section
Comment. on the Propo.ed ~emedy for ~he We.tarn Sand'
Gravel
-'
RE:
DATE:
March 13, 1iil
.
As requested, the DEM Croundwater Section has reviewed ~e
propo.ed remedy, a8 it per~ain. to groundwater contamination, for
the Western San4 , Gravel NPL lita. ~he following outlines our
objection to the EPA'a proposal to rely on natural attenuation to
achieve restoration ot the aquifer. Sucb an approach i. in .
conflict with Itate .ta~uta. and policies pertain!ni to
groundwater protection and restoration.
Remediation Goal
On page 7 0: the document outlinin; !PA's analy.il of
remedies tor the .ite, the re:ediation 90al tor qroundwater i.
tied to drinking water Itandard. or maximum contaminant level.
(HCLs). We concur ~at the HCLs are ~e appropriate standards
for qroun~water at an~ around the 'ita, excepting the araa which
underlies the capped fill on the aite... DEM would expect the
qroundwater baneath the fill ~o likely. remain degraded below
MCLs.
~h. ra=adial investigation clearly identifi.d the oft-sit.
migration of contaminant. in qrounc!water. our review of the
available intormation indioate. that there contiDues to be an
area ot qroun~watar contamination to the 8cuth/8outhwest ot ~e
tilled portion ot the site wbich exhibit. levels of contamination
in a range of ever 1,000 ppb tor total VOQ's. ~hi. area, it 18ft
unaddr...ad,'repre.ent. a con~inuing source of qroun4water
contamination 1n the 4own~adi.nt aquifer area. ~he Groun4watar
Section beli.ve, that, 4ue to the aite'condition., groundwater
classification and other factor., thil portion ot the lite
-------
.
a tailure to take additional action to promote remediation ot
apactad vroundwater at thi. .ite would be a oonflict with the
Rhoda I,laneS Croundwater Protection Act (JUGWPA), IlIGL 42-13.1,
R1 Wa~.r Pollution Control Act, RIGL 46-12 and tha policia.
routibaly u.ad by the Croundwater Saction to 1mplament 'the
statute. an~a..ociate4 regulation..
.
~eable Sta~a Pol~e.' R8aardinq Creundwatar
The state policies pertainin; ~o qroundwater pro~ection are
outlined in tha RICWPA which amon; othar items require. that 811
;roundwater be cla..ifiad. In developing re;ulation8 to
implement tha Act, the Groundwater Section has devi.ad a
;roundwata~ clas8ification .y.te. which embodia. . policy of
difterential protection. A8 explainad in detail in the
cla..itication 8trategy, the .tate policy allow. ~EM to racoqnile
the variable value ot the .tate. groundwater resource..
consistent with thi., the DEM Croundwater' section, through its
exi.ting proqrama, impose. clean-up standard. that reflect the
pclicy of 4iftarantial protection. lor exampla, . .ita
cl..sified a. 01 will be treated differently than 8 .ite
ela.sifiad .. GA (suitabla fcr drinking water without traatment.)
While tha policy of ditterential protecticn allow. DEM a .
cartain tlaxibility in protection of the .tata'. ;roundwatar,
tha RIGWPA .imultaneou.ly has mandated a .trOft; policy of
~..toration and non-deqradation. ~i. i. reflacted in tha .
tcllcwin; lanqua;a from the Act: Cbapter13.1, 46-13.1-2.
(3) It 18 a paramount policy of 'tha .tata to protect the
purity ot p~e8ent and fut~e 4rinkin; watar .upplie. by .
protectin; aquitar8, raehar;e area., and watar.hed.;
(4) It i8 a policy of the .tate to restore and maintain the
quality ot qroun4water to a quality consi.tent with itl ~Ie for
drinkinq .upplia. and other 4a.lqnate4 ~aneficial u.a. without
treatmant aa taa.i~la. All ;roundwatarl of the .tate 8hall be
restorad to tha axtent practicable to . quality consi.tent with
thi. polioy, .
(5) It i. 'the policy of tha Itate not to perm1t the
inuoduction of »ollutant8 into tha ;:,oundwatar of the .tate 1n
concentrat1ona which are known to be to~ic, carcinogenic, .
mutagenic, or taratogenic. To tha maxtmum extent pra~ical,
ettort. .hall be made to require tha removal of IUch pollutant.
:trom di.char;a. where such di.charge. are .hewn ~o hava already
occurred,
(6) Ixi.tin; and potential .ource. ot ;roundwater Ihall b.
mainta1na4 and protected. Where e~istin; quality i8 inadequata
to lupport oarta1n u..., 8uch quality .hall be upgorade4 it '
t.a.i~la to protect the pr...nt and potential U." ot the
-------
SENT ~T;xerox teleCopler 1U'U , .-I~-DI
, 1£' "11"111 .
"w..''''''..'
In impl.men~inq the policies articulate~ in tn. Act, the DEM
Groundwa~er Section has consistently require~ an active approach
to grounawater contamination whenever fealible in area. in which
the qoal va. to return the resource to a drinkable wa~.r quality.
We cal~ att.ntionto the u.. ot the wor~inq .ma~1mum .xt,nt
practical" from 46-13.1-2. (5) ~hi8 i. how We believ.the
W.stern Sand' Qrav8l .it.' ahou14 be a4dr....d.
~forc.m.nt ot ActJV8 R8s~oration PoliCY .
In . ..etinq in February 26, 1991, DEM met with ZPA ~o
aiscuss more specifically how the Groundwater Section admini.ters
and enforo.a policies r89ardinq qroun~w.ter contamination. As
in41cated in the me.tinq the DEK Groundwater Section haa
consiatently required an ac~ive remediation approach at .ite.
located in QAA area. wher.ver feasibl. in ord.r to promote
re.toration ot the resource to a drinkable water quality. The
Groundwater Section relies on the author1tie. ot the Director a.
provi~e~ for in 42-17.1 an~ 46-12 to entorce all water quality
stan~ar4. and policies that pertain to aChievinq compliance with
.uch .tan4ard8. ~he .pecitic enforcement mechanism. which are
routinely utilized inclu~e Notice. ot Violation., Adminiatrative
Order. and Immediate Complianca Or4er8. Th... mechanilm., aloni
with the ability to entar into con.ent aqr.8ment., hava providea
tha maans by which DEM has r.quired active ramediation ot aite..
(S.e Attached) ~he mechanisms hava larqaly been suoce..ful in .
achiaving the implemantation ot remedie., although the Section
- will .tate that there exi.t oartain ca... Cc"t..ted by the
taeili ty or.' prcparty cwnara and th.retor. c;roundwater traatment
.y.tem. have yet tc be in.talled and activated pendinq final
admini.trative ad~udiQ~tory or cour~ action. Saveral ease are
currently pendin; with the n.w Admini.tratio" A~judieation
Division ot CEM.
A8 to cur track record, tha CEM Groundwater Section deal.
with a variaty of contaminated lita., including tho.a re.ul~ini
from .eakinq underqround Itora;e tank. (LUST.). A preliminary
raview of LUST .ite. raveala the following:
~otal number of site. 14entitied
Number lite. ramediation complete4/clo.ad
Number aite. with on-qoinq activity
NWlHZ' 8it.. in GAl Area
217
85
122
28
Statu. of Si~.. in G1A ~r.a.
Activ. rame~iation on-qcing
(80il venting/pump' treat)
Ordared or required ~o implement active
re~adiation (not yet operational)
10
-------
SENT ~y:x,rox leleCOOler 1U~U , '-1~-„1 ,1~;la~M i
4U 1:'/4/,),) ,-
- "I I ...-v -.....~ ,. ."
.
.
. conduct.ing.. .ite .1nve.~i9ation. ~c
a.!e~. extent of ~elea.e of contaminan~.
Contam1nated .oi1 removed; no
further-action required (clo.8d ca...)..
6
7
-
other ***
1
Hote * New lite. are ident1fied on an on-;o1ng ~a.ia.
** No evidence of ;rcundwater contamination exh1bited.
*.. Thi. lite refer. to Canc~ Park which pre-dated the
exi.tence of nST regulation. and the RIGWPA.
Thi. review indicate. that where .ite tnspections and/or
inve.tigations identif1ed groundwater contamination, an ac~1ve
approach to r.mediation was required by DEM.
A complete ~eview of otber type. of aite. va. no~ possible
with the time frame allotted to DEM follow in; the .eeting.
Rowevar, 'the Sec1:1on ha. handled aite. involving VOC
contamination remediation and adheres to aimiliar policies in
entcrcement mattera pertaining to the Underground Injection
control Pr0CJram.
The w..tern Sand and Gravel .ita i. cla..ified CAA-- which
mean. the .ite lie. within the Z'ecbar;e area to one of th.
atate'a moat productive aand and ;ravel aquifer.. This
de.1;nat10n furthar .iiftifie. that it i. the .tate'a ;oal to
aaintain the qroun4water in a condition 8uitable tor drinking
wat.er purpo.e..
'1'he Groundwater Section ha. mapped the recharge areas 'to 20
groune!water resarvoir. whiCh were previously mappad by the JlI
Water Re.ource. Board. (See attachad aummary of method u.ad by
RIDEK) There 1. . C01\'.1\8\18 amon; atate official. and other.
tha~ tha.a aquiter areaa repre.ent the mo.~ p~04uotive, anc!
con.equently the .oat bi;h1I valued, portion of the .ta~e'.
;roundwatar reaource.. A h 9h prior1ty for protection i.
as.igned ~o the cr1tical portions of tha rechar;e area. 1n o~4ar
to pre.U'Va ~e a~ifer. value for ~cth pre.en~ and future watar
aupply n.ee!l. The presence at a p~lic water lina doe. not
na;&te the value of the re.ource or 41min1ah the fteed to protect
it..
In recoqnition of tha .pecifio condition. at the We.tern
Sand , Graval .ite, the Gro\mdwa~ar section hat further
d..ignatae! portion. of tha .ite both OS and au Non-attainment.
At wa.te di.po.al ait.., the OS Claa.iticat1on i. r.atricted to
the actual wa.te di8posal area. ~ha GAA/NA 4e.iqnat10ft applies
to vroundwater ~ayone! the .ouree ar.. that 1. not. 4rinkinq water
-------
SeNt DY'AerOX leI8Cg~lV~
IU~U , "-'''-01
, I&.' ..rlll ,
~.._...,..._.
.
quality, therefore it il not in compliance with the GAA
Standar4.. The foal for groundwater de.ignated CAA-NA i.
re.toration to 4rinkinq water quality. The GAA-NA de.ignation i.
ba.ed Qn mon1toring well data and any other information
indicating areas that do not me.t the .tandard..
In delineatin9 the.rea cla..ified CS and de.iqnated GAA-NA
at W..tern Sand and Cravel, the Rem.dial
Inve.t1;ation/F.a.i~ility Study, Kay 22, 1i84 was u.ed. U.ing
Figura 1-2 of ~e RI/IS the area labeled M.1te" va. cla..ified GB
and the area labeled "affected are." wal de.iqnated CAA-NA. At
the time 0: our groundwater cla..ification delineation., this was
the be.t available intormation. Re.toration.of the area
designated GAA"NA i. ~elievec! fea.ible.. Site condition. are not
known to be 8uch that remediation technologi.. would be arguably
inetfective; 8uch a. miqht be found with contamination in .
fractured ~edrock.
As more reliable qroundwater data become. available about
thi. aite or any other aite in the atate, the groundwater
clas.ification may change. The criteria, or method u.ed to
delineate GS and GAA-NA will remain the .ame. However ~e
intormation u..d in applying the criteria will be updated, (i.)-
new ;roundwater data.
Givan the GAA-NA de.ignation tor groundwater beyond the
waate area that 40.. not meet the QAA atanda~d., the Qroundwater
- Section believe. that activa treatment ot the mOlt contaminated
CIZ'oundwater is nece..ary and required under the RIGWPA. Thi.
would ~. con.i.tent with other DIM Groundwater Section deoi.ion.
reqard1nq .imilar Voc. oontamination incident. in GAA are...
Natural attanuation i. unacceptable for the following reasons:
d.
a.
Tha site cla..ification ,. GAA mandate. all rea.onable
efforts be made to remadiate exi.ting contamination.
DEM believe. groundwater treatment i. rea.onable
approach.
the .ite 11.. upqrad1ant ot property that .ay ~e
developed ut111z1n~ private well.. ~h. Oroun4wat.r
Section i. not eontidant that temporary acc...
reltriction. wou14 effectively prevent _11 tuture
development.
J:).
0.
The aite conditione appear to ~e amenable to
qrounc!\'ater treatment. Active remediation i. not
con. trained ~ technical teasibility concern..
.Ther. has been ftO 'howinq-economic, technical or
otherwi.e-that it ia unrea.onable to require active
qroundwater treatment at the .it.. The DEM Groundwater
-------
'.-.' .,..
. - .. ,1'. .......... ~ . ..
0.""" . ~ ,.., ". .W
.
.-
propoled treatmant option. may ba higher" than
nec...ary. La.. co.tly ~rea~.n~ .y.~am. appear ~o b.
. available.
In:.umma~~, natural attenuation doe. not do anything ~o
promo~. re.toration of groundWater at ~e Wel~arn Sand' Oraval
.ite.-Th. DEM Groundwater section findl that thi. ,ropolal il
therefore in conflic~ vi~ .tat. polici.. concerning ~e
r.ltoration Of groundwater. To 40 otherwi.e in thil cale woul~
.et . preoedent that .u;;..~. that i. a aoceptable to ~~.lum8
that ;roundwater contaminant concentration. will decline over
18n;thI period. of time. W. remain unconvinoed of the
rellab lity of the ~oun4water .cdelin; upon which the analYli.
of alternative. i. ~a.ed. . %Yen with an effective monitoring
program, ZPA'. propo.ed approach, if adopted:. widely would
effectively r~n4er an increaling portion of the .ta~e.
vroundwater re.ourc.. unulable for lon; period. ot time. Thi8 i.
clearly not the approach the DEN .hould be encouraging.
co:
~. 'ester
s. Morin
-------
RHODE ISUND tlEPAD!!Nl' 01 ~ ~
A SUZmna:y ot ~. AnA Mappin; to
~Ur RasL~in tor QAA Clus1:icat.ion
-I,
.
-~ Jhcc5a %alw Grcun:!wttar Prct.Ict1cn Act ot 1;85 ~ the
Grcundwate S-=-..icn of 't.'w ~ %&lw ~ ot !:nvirc:I'D8nta
. Mar.aqCD8nt (1U C!M) to clu8i:Y t:'A mta '. ~t8r ~ \2111:1; a
tcur clau 8",iRE an:! to 48v81cp Itan:!ama for aac:h clu8Uleaticn. ~
g%'CImdwatar cluaitied cw. is cr::nsidand the ltata '. =-t valuBl.
~tar ~ W will ncaiV8 the h19hM't 18Y8l ot ~.
~ -jar c::crt;cn8nt ot the ~4tu clusified ca\A u t.h8 crit.ic:al
portion ot th8 nc.~ &t'8a to tb8 ~'at.tr ~izII. '%he .
~~ ftMrYC1n &r8 the h1;hat y1a1c!in; ~.1cma ct the 8'tata '.
8'tmtitied drift aquifers (at'.:-ata:!~.ickn88s gnaw than ..0 f~ 8:'4
tnnsmisBivity ;natar than 4000 f..~ ~ pc" day) t.'-.t u. capel. ot
servin; .. a significant sourca cf PJ!:lic m:pply.
I%he ~ IIlw Otf1ca cf ~ u.s. QeQlo;ic&l ~ffi baa ~ a
~J:d to .., the ~ areu to the ~t8r %'88C'VOir8. :his
-thcd wu ~tieC ~ RI CD( fer UM in ~tar c1...~ic:a't1on
-win;. h n.::."'.a:va area mappini -~lClgy dat1nes thne ~
ZCX188 :
Aquilar A%'U8 -
Adjacent Ar8u -
t.".. ~tc :'IMrVQ1ra a:x! ~ ot tJ'18
~ 8t2:'aWied cb:1ft.
area ot t.i1l ~ ~~ f:tD t.1h.1ch ~tI:' that:
percclate8 to the W&tar ~. tlC1W8 th.rc:u;b tba
8'WbIurfaQ8 to t.~ aqW.ter ana w1~ t1Dt:
~ to a ~ 8t:um.
~ tninat;a
Me.u -
the ~ usa ot Irti 8U1"fac8 water \;8b:um
tr= tha ~8%' C8& ~.
~ ~tar Sect:icn has c5u1grated t.~ aqW.fer 8ftU and adj~
8r8U .. the c:itic:a1 pcrticn ot th8 ftd-.ar;a ana to th8 ~t.c
~1:s. 'IheM C"8U will be clU81tied QAA (... F1;ut'8 1.).
In 1IIpp1ni the ~ aruI tc tha ~t8r ~in, ~ rAW
~loiic c!ata was coll8Ct8!. '1'h8 d8lin8aticrw are bu8cS on
%'8UCInIb1y IWAf~~l. W==atJ.an en tha ~8Olc:q1c ~
u~1at81S with ucb ~t.Ir Z'88CYCir. ~'JM of the ~18Xiti8s
of ~tC' tlQW, MYWnJ. .~l1fY1n; ~cna hava *n 1IIde,
~\1I:!:in;1 .
. - Wh8r8 watar tCl. cSata 18 net ~1., the 14W'~. 8Urfa=e
18 ccn8~ to m1mic 8UZ'tace tcpcr;tapby.
- All ot th8 ~t.er ot . win Car ~in) di8ct~ tc tha
penmial 8tru.m Cdalinut8:! en th8 USGS ~l.) that datinM
-------
" . ~
" '" ...
-~ 0)
, I
I
'.
(
"
~ ..-
~-
/
I
,./ .
~
~
/
\
.
\
;; Aquif.~ u.a
lID Adjacent ~I.
(J Vp.c-r... J)l'Uua' ...~..
_-I)~as.u.' I.d.n Icnm4ary
- 'f111/Sc~acUi,4 1)~Ut Contact
- - Groa4vacu ""'1Noi-r JouDc1a~
.-+- S tor....
rilUrl 1.
lypOtblC1cal draiDA,' ba.in Ihovinl th, 41fflfiDt rlchar,a 80n.' to
-------
..-... -. . .,.. ..
DR"AFT GROUND1V A T]R CLASSIFICATION
-. .
RHODE ISLAND DEPARTMENT OF E~VIRO~MENTAL MANAGEMENT
.
,I.
",'
~ 0
,
~
, ..-
-.~.T.._..--r.
~Q . ~ \.
, v ,
~ ' I *
V ' , .
, r -w '
t ,
, ,
, ,
I ,
- - - - . - .. . . - - - - --- . -
~ "
. ~ I I
-------~- ~~~.-
I
I
I
I
---a-------
GROUNDWATER CLASSES
~ CAA
o GA
m CB
[!] GC
~ Town Boundaries
G
*
SCALE 1 : 420,000
1
I
HOT!!: Ctoundw:lter clCSliftc:tionl "F' delltlelt.d 811 1 : 24,000 ICel. ~.!. C.o1cfc= .
~Y" quachnglt mop.. It.flt t. tilt" ",apl It Ute Grounel.at" $tctlaft, RJ. DEW
. f. 8ftt ".cia. ""tloft " tba .._.ater cluJif1cotiw.
WIthin ttli t"OIIftdwotll' clOIai"1d eM 814 CA '" tM tUv. map or, arias ""Ir. tilt
tL DOl 110. .8termiMd tIIat ttl. ,0000001ter dOli ut Nit .tarlft1'4. fit CM GIld
CAe 1",,, areol .., cdtG GAA - Nonattainmtftt - GA - Honattcil'lll'llllt. 8M tI\e
-4-181'," ;ocl it ,,,torouon to GAA ",d GA .tOftdardl. R,f.r to IOrglf' .colt mopl
,rodl:ctd by R.l D£\I for Uti dtGn,atiClrl of tll... nonatU1l'lme!:t arlCI.
.
~
(e) ... MCIS
18ft If o,.8PMM I" Itpt C*"
AI 11"'1 _'H,.t4
-------
. .
APPENDIX F
RECORD OF DECISION
WESTERN SAND , GRAVEL SITE
-------
.
.-
-Western Sand & Gravel
NPL Site Administrative Record
~
Index
Compiled:
Updated:
Updated:
ROD Signed:
March 16, 1990
November 21, 1990
February 4, 1991
April 16, 1991
Prepared for
Region I
Waste Management Division
U.S. Environmental Protection Agency
With Assistance from
. . . AMERICAN MANAGEMENT SYSTEMS, INC.
-------
.
IntrMlaction
This docUment is the Index to the Administmtrve Record for the April 16, 1991 Record of
Decision (Operable Unit ill - Groundwater Reme4f) for the W.estem Sand and Gravel National
Priorities Us~ (NPL) site. Section I of the Index oite& 'liite-speQffic documents and Section IT cites
guidance documen1S used by EPA staffil'.sdecting:aJresponse action at the site.
The Administrative Record is available for-public review at EP A Region I's Office in Boston,
Massachusetts and at the lhmiDville Town Building, 1{)s Harrisville Main Street, Harrisville,
Rhode Island 02830. This Administraiiw!Record includes, by rllference only, all documents
included in the Administrative Record/orrihe September 28, 19M/Record o/Decision (Operable
Unit 1- Temporary Domestic Well Treatment anil Per1fIJIDe:nt Alternative Water Supply) and the
Administrative Record/or the September 30, lJIK5 Record 0/ Decision (Operable Unit 11 - Source
Control). Questions concerning the Acbninillr'.rtive Record.rJmu1d be:addressed to the EPA
Region I site manager.
The Administrative Reoon:i is requimi by!t2ComprehenBive Environmental Response,
Compensation, and liability Act (CERCLA), asaIJmmded by the~rfund Amendments and
Reauthorization Act (SARA).
-------
. .
."
Section I
Site-Specific Documents
-------
ADMINISTRATIVE RECORD INDEX
for the
Westem Sand and Gravel NPL Site
..,.-
(Groundwater Remedy. Operable Unit llI)
3.0
Remedial Investigation (RI)
3.1 Correspondence
Agency for Toxic Substances and Disease Registry (A TSDR)
1.
Letter from Lynne A. Fratus, EP A Region I to Louise House, Agency for Toxic
Substances and Disease Registry (A TSDR) (March 2, 1990). Concerning
transmittal of the Draft Remedial Investigation Report.
Letter from Lynne A. Fratus, EP A Region I to Louise House, Agency for Toxic
Substances and Disease Registry (A TSDR) (April 2, 1990). Concerning
ttansmiual of Appendix 0 of the February 1990 "Draft Groundwater Remedial
Investigation Report," Olin Corporation.
Camp Dresser & McKee me.
3. Memorandum from Jan Drake, Camp Dresser & McKee Inc. to Lynne A. Franis,
EP A Region I (June 15, 1989). Concerning review of contamination of the
bedrock aquifer. .
4. Letter from Karen Stone, Camp Dresser & McKcc Inc. to Rose Harvell, EP A
Region I (June 27, 1989). Concerning the attached "Letter Report: Review of
Olin's Stream and Surface Water Assessment," Camp Dresser & McKee Inc.
(May 12, 1989).
5. Letter from John Wa1ker, Camp Dresser & McKee Inc. to Jack Jojokian, EP A
Headquarters (July 14, 1989) with the attached "Draft Report Review ofPRP's
Data Validation Report" (July 14, 1989).
Olin Corporation
2.
6. Letter from John W. Gallagher, EPA Region I to Verrill M. Norwood Jr., Olin
Corporation (August 4, 1986) with the attached Telephone Notes between John
W. Gallagher, EPA Region I and Margaret Leshen, EPA Region I
(August 4; 1986). Concerning follow-up of July 29, 1986 meeting held to
discuss cleanup of site
7. Letter from John W. Gallagher, EPA Region I to James C. Brown, Olin
Corporation (September 4, 1986). Concerning the groundwater study.
8. Letter from James C. Brown, Olin Corporation to John W. Gallagher, EPA .
Region I (September 12, 1986). Concerning clarification of agreements made in
the September 4, 1986 conference call.
9. Letter from Michael J. Bellotti and Robert D. McCaleb, Olin Corporation to John
W. Gallagher, EPARegioo I (January 12, 1987). Concerning clarification of soil
samples.
10. Letter from John W. Gallagher, EPA Region I to James C. Brown, Olin
Corporation (August 3,1987). Concerning summary of the July 30,1987
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Page 2 .
3.1
Correspondence (cont'd.)
Olin Corporation (cont'd.)
11. -Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A
Region I and Felix Harvey, State of Rhode Island Department of Environmental
Management (March 8, 1988). Concerning Groundwater Remedial
InvestigationlFeasibility Study and closure field activities.
. 12. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin Corporation
(March 14, 1988). Concerning certification of approval for Groundwater
Remedial Investigation Site Operations Plan.
13. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A
Region I (March 21,1988) with attached model letter and well installation
agreement. Concerning inability to obtain access to Lot 7/38 in North Smithfield.
14. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EPA Region I
and Felix Harvey, State of Rhode Island Department of Environmental
Management (April 26, 1988). Concerning disposal ofpcrsonal protective
equipment.
15. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin Corporation
(May 5, 1988). Concerning approval of contractors.
16. Letter from Richard Boynton, EP A Region I to James C. Brown, Olin
. Corporation (June 2,1988). Concerning disposal of personal protective
equipment and additional approval of analytical labs.
17. Letter from Richard Boynton, EP A Region I to James C. Brown, Olin
Corporation (June 2, 1988). Concerning approval of Project Operations Plan.
18. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EPA .
Region I and Wmen S. Angell IT, State of Rhode Island Department of
Environmental Management (July 22, 1988). Concerning Phase IT Groundwater
Remedial Investigation/Feasibility Study well installation.
19. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin Corporation
(J.uly 27, 1988). Concerning split sample results.
20. Letter from Robert D. McCaleb for James C. Brown, Olin Corporation to Lynne
A. Fratus, EPA Region I (August 19, 1988) with the attached specification sheets.
Concerning piezometer installation and specifications.
21. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin Corporation
(August 24, 1988). Concerning the bedrock well at CW-4.
22. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin Corporation
(April 5, 1989). Concerning the March 28, 1989 meeting regarding Olin
Corporation's fmdings and conclusions for the Remedial Investigation.
23. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(August 7, 1989). Concerning fmdings from Olin Corporation's investigation of
alternate bedrock monitoring well installation and sampling techniques.
24. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(October 27, 1989). Concerning EP A's review of the draft GR! report.
25. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A
Region I and Wmen S. Angell IT, State of Rhode Island Department of
Environmental Management (January 9,1990). Concerning disposal of soil and
bedrock samples.
26. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A
Region I and Wmen S. Angell IT, State of Rhode Island Department of
Environmental Management (January 11, 1990). Concerning Olin Corporation's
designation of David L. Cummings as coordinator. .
27. Letter from Lynne A. Fratus, EP A Region I to David L. Cummings, Olin
Corporation (January 22,1990). Concerning response to the Janumy 9,1990
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Page 3 .
3.1
COrre5l1Ondence (cont'd.)
Olin Corporation (cont'd.)
28. Letter from Lynne A. Fratus, EP A Region I to Robert D. McCaleb, Olin
Corporation (February 6, 1990). Concerning tranSmittal of the December 1988
"Guidance OIl Remedial Actions for Contaminated Groundwater at Superfund
Sites."
29. Letter from David L Cummings, Olin Corporation to Lynne A. Fratus, EPA
Region I and Warren S. Angell n, State of Rhode Island Department of
Environmental Management (February 26, 1990). Concerning the attached:
A. Cross Reference: "Draft Groundwater Remedial Investigation Report,"
Olin Corporation (February 1990) [Filed and cited as entry number 3 in
3.6 Remedial Investigation (RI) Reports].
B. Cross Reference: "Draft Groundwater Remedial Investigation Report -
A~ A-M," Olin Corporation (February 1990) [filed and cited as
entry number 4 in 3.6 Remedial Investigation. (RI) Reports].
C. Cross Reference: "Draft Groundwater Remedial Investigation Report -
Appendices N-U," Olin Corporation (February 1990) [Filed and cited as
entry number 5 in 3.6 Remedial Investigation (RI) Reports].
D. Cross Reference: "Draft Groundwater Remedial Investigation Report -
~ AA-AE," Olin Corporation (February 1990) [Filed and cited as
en1ry uumber 6 in 3.6 Remedial Investigation (RI) Reports].
30. Letter from Robert D. McCaleb for David L. Cummings, Olin Corporation to
Lynne A. Fratus and Warren S. AngeU n, State of Rhode Island Department of.
Environmental Management, EP A Region I (March 16, 1990). Concerning
tranSmittal of Appendix 0 of the February 1990 "Draft Groundwater Remedial
Investigation Report," Olin Corporation.
31. Letter from Lynne A. Fratus, EP A Region I to Robert D. McCaleb, Olin
Corporation (March 16,1990). Concerning transmittal of the October 25,1985
"Draft Focused Feasibility Study Report," Camp Dresser & McKee Inc.
32. Letter from Robert D. McCaleb, Olin Corporation to Warren S. AngeU n, State of
Rhode Island Department of Environmental Management (April 10, 1990).
Concerning confumation of the State of Rhode Island Department of
Environmental Management's address.
33. Letter from David L. Cummings, Olin Corporation to Warren S. Angell II, State
of Rhode Island Department of Environmental Management (April 11, 1990).
Concerning request for approval or comments on the February 1990 "Draft
'. . Groundwater Remedial Investigation Report," Olin Corporation.
. 34. Letter from David L Cummings, Olin Corporation to Lynne A. Fratus, EP A
Region I and Warren S. AngeU n, State of Rhode Island Department of
Environmental Management (June 22, 1990). Concerning the attached:
A. Cross-Reference: "Draft Groundwater Remedial Investigation Report,"
Olin Corporation (June 1990) [Filed and cited as entry number 7 in 3.6
RemceJja) Investigation (RI) Reports].
B. Cross-Reference: ''Draft Groundwater Remedial Investigation Report -
Partial Appendices," Olin Corporation (June 1990) [Filed and cited as
entry number 8 in 3.6 Remedial Investigation (RI) Reports].
The mops associDted with the record cited as enl1'y number 35 are oversized and may be
reviewed, by appointment only, tlI EPA Region 1, BostOn, Massachusetts.
35. Letter from Robert D. McCaleb for David L Cummings, Olin Corporation to
Lynne A. Fratus, EP A Region I and Warren S. Angell n, State of Rhode Island
Department of Environmental Management (August 10, 1990). Concerning
transmittal of attached figures and maps to be inserted into the June 1990
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.
Page 4
3.1 Correspondence (cont'd)
0!in Cmporation (cont'd.)
..
.. .
36. Letter from Robert D. McCaleb for David L Cummings, Olin Corporation to
. Lynne A. Fratus, EPA Region I and Warren S. Angell n, State of Rhode Island
Department of Environmental Management (August 27, 1990). Concerning
notification that Olin COrporation will sample OR! wells during the week of
August 27, 1990.
37. Letter from Robert D. McCaleb, Olin Corporation to Burrillville Police
Department (September 19, 1990). Concerning notification of acts of vandalism
at the site.
38. Letter from Richard C. Boynton, EP A Region I to David L Cummings, Olin
Corporation (October 25, 1990). Concerning disapproval of the June 1990
"Groundwater Remedial Investigation Report," Olin Corporation.. .
39. Letter from Richard C. Boynton, EPA Region I to David L. Cummings, Olin
Corporation (October 31, 1990). Concerning the need for additional
groundwater data and the testing of samples for volatile organic compounds.
40. Letter from Robert D. McCaleb for David L. Cummings, Olin Corporation to .
Lynne A. Fratus, EP A Region I (November 1, 1990). Concerning transmittal of
the following attachments:
A. Cross-Reference: "Groundwater Remedial Investigation - Text," Olin
Corporation (June 1990) [Filed and cited as entry number 10 in 3.6
Remedial Investigation (RI) Reports]. -
B. Cross-Reference: "Groundwater Remedial Investigation - Appendices
A-M," Olin Corporation (June 1990) [Filed and cited as entry number 11
in 3.6 Remedial Investigation (RI) Reports].
C. Cross-Reference: "Groundwater Remedial Investigation - Appendices
N-U," Olin Corporation (June 1990) [Filed and cited as entry number 12
in 3.6 Remedial Investigation (RI) Reports].
D. Cross-Reference: "Groundwater Remedial Investigation - Appendices
AA-AF," Olin Corporation (June 1990) [Filed and cited as entry number
13 in 3.6 Remedial Investigation (RI) Reports].
41. Letter from David L Cummings, Olin Corporation to Lynne A. Fratus, EPA
Region I and Warren S. Angell II, State of Rhode Island Department of
Environmental Management (November 6, 1990). Concerning notification that
groundwater sampling will be conducted November 8,9, and 10, 1990. .
42. Memorandum from Robert D. McCaleb, Olin Corporation to WarrenS. Angell II,
State of Rhode Island Department of Environmental Management
(November 12, 1990). Concerning transmittal of sampling notes.
43. Letter from Bruce R. Cushing, BCM Engineers to Warren S. Angell II, State of
Rhode Island Department of Environmental Management (November 12, 1990).
Conetming transmittal of the "Biological Assessment Field Log Book" for review.
44. Letter from Robert T. Hart, Chemwest Analytical Laboratories, Inc. to Mickey
Cartegena, CompuChem Laboratories, Inc. (November 15, 1990). Concerning
transmittal of the attached data for November 9, 1990 sampling.
45. I.dter from William Walsh-Rogalski, EPA Region I to Gregory L. BeniIe,
Hinckley, Allen, Snyder & Comen (Attorney for Olin Hunt Specialty Products
Inc.) (November 20, 1990).. Conce_"Ding EPA's proposed resolution of the
dispute concerning disapproval of the June 1990 "Revised Groundwater Remedial
Investigation Report, " Olin Corporation.
46. Letter from David L (:ummings, Olin Corporation to Lynne A. Fratus, EP A
Region I (November 21, 1990). Concerning transmittal of the attached "Draft
Summary of Groundwater Monitoring Well Data."
47. Letter from Lynne A. Fratus for Richard C. Boynton, EP A Region I to David L.
Cummings, Olin Corporation (November 23, 1990). Concerning ttansmittal of
the Addendum developed by EP A Region I to the June 1990 "Revised
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.
Page 5
3.1 Correspondence (cont'd.)
Olin Corporation (cont'd.)
48. -Letter from Elaine Wong, Chemwest Analytical Laboratories, Inc. to Rick
Camp, CompuChem Laboratories, Inc. (December 7, 1990). Concerning
transmittal of tile attached additional data for the November 9, 1990 sampling.
. 49. Memorandum from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus,
EP A Region I (December 13, 1990). Concerning transmittal of the attached
groundwater monitoring weD data summaries.
50. Letter from Richard C. Boynton, EP A Region I to David L. Cummings, Olin
Corporation (February 7, 1991). Conccming a request that Olin Corporation
conduct an investigation of the bedrock at the site. .
51. Letter from David L. Cummings, Olin Corporation to Lynne A. Fratus, EPA
Region I (March 11, 1991). Concerning notification that Olin Corporation plans
to install and sample additional bedrock wells between the site and the residential
neighborhood northwest of the site.
State of Rhode Is1and Department of Environmental Management
52. Letter from Lynne A. Fratus, EPA Region I to Wmen S. AngeU n, State of
Rhode Island Department dEnvironmental Management (March 23, 1990).
Concerning request for transmittal of the list of Applicable or Relevant and
Appropriate Requirements (ARARs) as identified by the State of Rhode Island.
53. Letter from Lynne A. Fratus, EPA Region I to Wmen S. AngeU n, State of
Rhode Island Department of Environmental Management (March 28, 1990). .
Concerning transmittal of the results of the screening of alternatives and request
for a draft list of the action specific Applicable or Relevant and Appropriate
Requirements (ARARs) as identified by the State of Rhode Island.
54. Letter from Lynne A. Fratus, EPA Region I to Wmen S. AngeU n, State of
Rhode Island Department of Environmental Management (April 17 , 1990).
Concerning transmittal of notes from the April 16, 1990 meeting and the
August 1988 "CERCLA Compliance with Other Laws Manual: Part ll."
55. Letter from Lynne A. Fratus, EPA Region I to Wmen S. AngeU n, State of
Rhode Island Department of Environmental Management (May 10, 1990).
Concerning transmittal of the August 1988 "CERCLA Compliance with Other
Laws Manual - Part L" .
56. Letter from Richard C. Boynton, EPA Region I to Alicia M. Good, State of
Rhode Island Department of Environmental Management (October 29,1990).
Concerning progress at the site, transmittal of the attached October 26, 1990
''Draft GroundwaterRemcdial Investigation Report Addendum," EP A Region I
for comments, and the Letter from Richard C. Boynton, EP A Region I to David
L. Cummings, Olin Corporation (October 1S, 1990).
57. Letter from Wmen S. AngeU n, State of Rhode Island Department of
Environmental Management to Richard C. Boynton, EP A Region I
(November 5, 1990). Concerning transmittal of major fmdings regarding the
biological assessment.
58. Letter from Lynne A. Fratus, EPA Region I to Warren S. AngeU n, State of
Rhode Island Department of Environmental Management (November 6, 1990).
Concerning the meeting scheduled for November 9, 1990 regarding the
Remedial Investigation Report.
59. Letter from Lynne A. Fratus for Richard C. Boynton, EPA Region I to Alicia M.
Good, State of Rhode Island Department of Environmental Management
(November 23, 1990). Concerning transmittal of the Final Addendum to the
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Page 6 .
3.1 Correspondence (cont'd.)
State of Rhode Island Department of Environmental Management (cont'd.)
60: Letter from Warren S. Angell n, State of Rhode Island Department of
&vironmcntal Management to Lynne A Fratus, EPA Region I
(Dece~ 20, 1990). Concemitig transmittal of the attached infonnation
concerning the State of Rhode Island Water Quality Regulations.
- 61. Letter from Paul Kulpa,.State of Rhode Island Department of Environmental
Management to Lynne A. Fratus, EP A Region I (February 4, 1991).
Concerning notification that remedial activities have not addressed Non Aqueous
Phase Liquids (NAPLs).
62. Letter from WarrenS. Angell n for Claude Cote, State of Rhode Island
Department of Environmental Management to Gregory L Benik, Hinkley, Allen
Snyder & Comen (Attorney for Olin Hunt Specialty Products, Inc.)
(March S, 1991). Concerning a reqUest for additional sampling and the attached
Memorandum from Carlene Newman, State of Rhode Island Department of
Environmental Management to Alicia M Good, State of Rhode Island
Department of Environmental Management (January 15, 1991).
3.2 Sampling and Analysis Data
1. Letter from Anita C. Rigassio, Camp Dresser & McKee Inc. to Nancy Barmakian,
EP A Region I (December 28, 1987). Concerning the attached organic analytical
data from two low level water samples from Camp Dresser & McKee Inc. .
2. Letter from Anita C. Rigassio, Camp Dresser & McKee Inc. to Nancy Barmakiln,
EPA Region I (December 29,1987). Concerning the attached "Inorganic
Analytical Data from Two Low Level Water Samples," Camp Dresser & McKee.
Inc.
3. Memorandum from Jan Drake, Camp Dresser & McKee Inc. to Lynne A Fratus,
EPA Region I (May 11, 1988). Concerning attached well samples.
4. Memorandum from Jan Drake, Camp Dresser & McKee Inc. to Lynne A Fratus,
EPA Region I (July 21,1988). Concerning the attached "Certificate of Laboratory
Analysis," Camp Dresser & McKee Inc. (July 12, 1988).
3.4 Interim Deliverables
.
..'
Reports
Camp Dresser & McKee Inc.
1. Letter from Jan Drake, Camp Dresser & McKee Inc. to Lynne A. Fratus, EP A
. Region I (February 18,1988). Concerning field oversight report.
2. Weekly Status Report Summary, Camp Dresser & McKee Inc. (April 19, 1988).
3. Letter from Lynne A Fratus, EP A Region I to Jan Drake, Camp Dresser &
McKee Inc. (May S, 1988). Concerning the attached "Western Sand and Gravel
OW RI/FS CDM Split Sampling Plan," Olin Corporation (April 4, 1988).
4. Memorandum from Jan Drake, Camp Dresser & McKee Inc. to Lynne A. Fratus,
EPA Region I (May 23, 1988). Concerning the attached "Sumnwy of Phase I
Sampling Event," Camp Dresser & McKee Inc. (May 1988).
5. Letter from John WaJker, Camp Dresser & McKee Inc. to Rose Harvell, EP A
Region I (July II, 1988). Concerning the attached "Quality Assurance Project
Plan," Camp Dresser & McKee Inc. (July 11, 1988).
6. Letter from Karen Stone for John Walker, Camp Dresser & McKee Inc. to Rose
Harvell, EPA Region I (January 6,1989). Concerning the attached "Draft Letter
Report: Organic Data Validation, Case 9615," Camp Dresser & McKee Inc.
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Page 7. .
(.
3.4 Interim Deliverables (cont'd.)
Reports - Camp Dresser & McKee Inc. (cont'd.)
7. - Letter from Karen Stone for John Walker, Camp Dresser & McKee Inc. to Rose
Harvell, EPA Region I (January 6, 1989). Concerning the attached "Draft Letter
Report: Inorganic Data Validation, Case 9615," Camp Dresser & McKee Inc.
(January 6, 1989).
8. Letter from Karen StOne for John Walker, Camp Dresser & McKee Inc. to Rose
Harvell, EPA Region I (January 10, 1989). Concerning the attached "Letter
Report: Summary of Split Sampling Oversight Activities," Camp Dresser &
McKee Inc. (January 10,1989).
9. Letter from Karen Stone, Camp Dresser & McKee Inc. to Rose Harvell, EP A
Region I (March 2, 1989). Concerning the attached "Draft Letter Report: Data
Validation," Camp Dresser & McKee Inc. (March 2, 1989).
10. Letter from Karen Stone, Camp Dresser & McKee Inc. to Rose Harvell, EP A
Region I (June 27, 1989). Concerning the attached "Letter Report: Review of
Olin's Assessment of Bedrock Aquifer Contamination," Camp Dresser & McKee
Inc. (June 27, 1989).
Olin Corporation
11. "Sampling Plan for Groundwater," Olin Corporation (June 1987).
12. "Construction Procedures and SpecifICations," Olin Corporation (June 1987).
13. "Quality Assurance Plan for Groundwater Remedial Investigation and Feasibility
Study," Olin Corporation (June 1987). -
14. "Quality Assurance Plan for Groundwater Remedial Investigation and Feasibility
Study and for Post-Closure Monitoring," Olin Corporation
(November 6, 1987).
15. "Sampling Plan for Groundwater Remedial Investigation and Feasibility Study
and for Post-Closure Monitoring," Olin Corporation (November 6, 1987).
16. "Construction Procedures and Specifications for Groundwater Remedial
Investigation and Feasibility Study and for Post-Cosure Monitoring," Olin
Corporation (November 6, 1987).
17. Letter from Robert D. McCaleb for James C. Brown, Olin Corporation to Lynne
A. Fratus, EP A Region I and Felix Harvey, State of Rhode Island Department of
Environmental Management (December 23, 1987) With attached Exhibits A, B .
and C. Concerning a description of the soil vapor survey technique.
18. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region
I and Felix Harvey, State of Rhode Island Department of Environmental
Management (March 8, 1988). Concerning transmittal of the attached
"Description of Current Situation," Olin Corporation (February 1988).
19. Letter from James C. Brown, Olin CorporatiOn to Lynne A. Fratus, EPA
Regi~ I (April 15, 1988) with attached replacement page 15 for the
November 6, 1987 "Construction Procedures and Specifications for Groundwater
Remed;a1 Investigation and Feasibility Study and for Post-Cosure Monitoring," .
Olin Corporation (November 6, 1987).
20. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region
I and Felix Harvey, State of Rhode Island Department of Environmental
Management (May 13, 1988) with the attached "Project Operations Plan," Olin
Corporation.
21. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EPA Region
I (May 26, 1988). Concerning Sampling Plan revision to use Teflon-coated
stainless steel cable.
22. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region
I (June 30, 1988). Concerning the attached "Appendix r' to the Description of
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Page 8 .
3.4 Interim Deliverables (cont'd)
Reports - Olin Corporation (cont'd)
23. - Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
and Warren S. Angell IT, State of Rhode Island Department of Environmental
~ement (July 1, 1988). Concerning transmittal ofpreliminmy data for
groundwater RIIFS and post-closure monitoring and the attached:
A. Attachment 1: Well Boring Logs.
B. Attat'hment 2: Chemical analytical results for the May sampling event for
Groundwater Remedial InvestigationlFeasibility Study and Post-Cosure
Monitoring.
C. Attachment 3: Bedrock Elevations and Contour Map.
D. Attachment 4: Water Elevations, typical piezometric gradient map, analysis
of vertical groundwater gradients.
E. Attachment S: Map and rationale for tentative Phase n well locations.
24. ''Report on the Findings of the Petrex Soil Gas Survey for BCM Eastern and Olin
Corporation," Petrex (July 1, 1988).
The maps associaled with the record cited in entry number 25 are oversized and may
be reviewed, by appointment only, at EP A Region I, Boston, Massachusetts.
25. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
and Warren S. Angell n, State of Rhode Island Department of Environmental
Management (July 20, 1988). Concerning transmittal of additional infonnation for
July 1, 1988 package, Base Map (D-T412-120-10-1), isopleths ofpotentiometlic
heads in each zone, and residential well data sununaIy.
The enclosures referred to the record cited in entry number 26 are oversized doCUTneIUs
and may be reviewed, by appointment only, at EPA Region I, Boston, Massachusetts.
26. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
and Warren S. Angell IT, State of Rhode Island Department of Environmental
Management (August S, 1988). Concerning transmittal of bedrock well
specifications and sketch, base map, historic welllocations-partiaI plan, base
contour map, domestic well water sUnunaIy maps, topographic sheets of site area,
composite topographic sheet of site area, and topographic sheet with Phase I and n
well locations.
27. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
'. , and Warren S. Angell n, State of Rhode Island Department of Environmental
Management (August 16, 1988). Concerning a proposal for analytical parameters
for the second round of sampling.
28. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(September 8, 1988) with the attached "December Revisions to Project Operations
Plan," Olin Corporation.
29. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(September 12, 1988). Concerning transmittal of the attached "September
Revisions to Project Operations Plan for Groundwater Remedial Investigation and
Feasibility Study and for Post-cIosure Monitoring," Olin Corporation.
30. Letter from Robert D. McCaleb for James C. Brown, Olin Corporation to Lynne
A Fratus, EPA Region I and Warren S. Angell IT, State ofRhocle Island
DepartmcntofEnvironmental Management (Novembec 22,1988). Concerning
. preliminary results of well installation and sample analysis associated with the
groundwater at site and attached maps.
31. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EPA Region I
(January 20,1989). Concerning transmittal of Exhibits A, B, and C of the Risk
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...
3.4 Interim Deliverables (cont'd.)
Reports - Olin Corporation (cont'd.)
Maps associated with the record cited in entry number 32 are oversized and may be
reviewed, by appointment only, at EPA Region 1, BoSton, Massachusetts.
c
.
"32. Leucr from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(April 11, 1989). Concerning transmittal of the attached ''Draft Data Validation
Review," BCM Eastern for Olin Corporation (December 1988).
33. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(May 12, 1989). Concerning transmittal of the attached "Surface Warer and
Sediment Assessment," Olin Corporation.
34. Letter from James C. Brown, Olin Corporation to John Zannos, EP A Region I
(May 18, 1989). Concerning transmittal of attached "Bedrock Investigation," Olin
Corporation.
35. Letter from Robert D. McCaleb for James C. Brown, Olin Corporation to Lynne
A Fratus, EP A Region I (July 18, 1989). Concerning transmittal of attached
"Addendum Number 1 to the Project Operations Plan ," Olin Corporation
(July 1989).
36. Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A Region I
(July 27, 1989). Concerning transmittal of attached "Exhibit A - Well Group
Selecnon for Risk Assessment," Olin Corporation.
37. Mtmc:nndum from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus,
EPA Region I (January 8, 1990). Concerning transmittal of the attached
"Groundwater Risk Assessment," Olin Corporation (January 8, 1990).
38. Letter from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus, EP A
Region I (April 18, 1990). Concerning transmittal of the attached "Flow Net
Evaluation," Olin Corporation (March 12, 1990).
Comments
Camp Dresser & McKee Inc.
39. Memorandum from Jan Drake, Camp Dresser & McKee Inc. to Lynne A Fratus,
EPA Region I (September 19, 1988). Concerning Olin Corporation's Phase I
Data and attached maps.
40. Memorandum from Bill Swanson, Camp Dresser and McKee Inc. to Lynne A.
Fratus and John Zannos, EP A Region I (December 1, 1988). Concerning review
of sampling and analysis at the site and attached maps and data.
41. Letter from Lynne A. Fratus, EP A Region I to James C. Brown
(June 29, 1989). Concerning transmittal of the "Draft Report: Review ofPRP
Data Validation Report," Camp Dresser & McKee Inc. (June 29, 1989).
Comments
EPA Region I
42. Comments Dated August 1, 1986 from John W. Gallagher, EPA Region I on the
draft "Quality Assurance Plan for Groundwater Remedial Investigation and
Feasibility Study andfor po~t-aosure Monitoring," Olin Corporation.
43. Comments Dated September 22, 1987 from Charles Porfert, EP A Region I on the
June 1987 "Quality Assurance Plan for Groundwater Remedial Investigation and
Feasibility Study," Olin Corporation.
44. Comments Dated January 21, 1988 from Lynne A. Fratus, EPA Region I on the
Groundwater Remedial InvestigationlFeasibility Study and Post-Cosure
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.
3.4 Interim Deliverables (cont'd.)
Comments - EPA Region I (cont'd.)
45. Comments Dated February 17, 1988 from Lynne A. Fratus, EP A Region I on
the November 6, 1987 "Sampling Plan for Groundwater Remedial Investigation
ancfFeasibility Study and for Post-Closure Monitoring," Olin Corporation.
Page 10
Responses to Comments
Olin Corporation
46. Response Dated August 7, 1987 from John C. Brown, Olin Corporation on the
August 1, 1986 Comments from John W. Gallagher, EPA Region 1
47. Response Dated January 21, 1988 from James C. Brown, Olin Corporation on
the "Olin Responses to Comments by US EP A (Conference Call of
January 13, 1988) on Western Sand and Gravel GroUndwater Remedial
InvestigationIFeasibility Study and Post-Qosure Monitoring Site Operations
Plan," Olin Corporation.
48. Response Dated January 27,1988 from Olin Corporation on the
January 13, 1988 Conference Call.
49. Letter Dated March 8, 1988 from James C. Brown, Olin Corporation on the
February 12, 1988 Conference Call with attached "Olin Responses to
Comments by US EPA on Western Sand and Gravel Groundwater Remedial
InvestigationIFeasibility Study and Post-Closure Monitoring Well Construction -
Procedures and Specifications."
50. Letter Dated March 29, 1988 from James C. Brown, Olin Corporation on the
attached February 17, 1988 Comments from Lynne A. Fratus, EP A
Region I, the attached March 14, 1988 Comments from Lynne A. Fratus, EPA
Region I, and the March 23, 1988 Conference Call.
3.5 Applicable or Relevant and ApproPriate Requirements (ARARs)
1. Letter from James Fester, State of Rhode Island Department of Environmental
Management to Merrill S. Hohman, EPA Region I (June 22, 1990). Concerning
the attached Applicable or Relevant and Appropriate Requirements (ARARs):
General
A.
B.
"Rhode Island Pretreatment Regulations," State of Rhode Island
(June 26, 1984). .
"Rhode Island General Laws of 1956 Title 46 - Chapter 12 - Water
Pollution."
"Regulations for the Rhode Island Pollutant Discharge Elimination
System," State of Rhode Island (June 26, 1984).
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Page 11.
3.5 Applicable or Relevant and Appropriate Requirements (ARARs) (cont'd.)
Air
,0"
. -D. "Sources Required to File Applications for Approval to Construct, Install,
or Modify," State of Rhode Island. '
E. - "Air Pollution Control Regulation No.7 - Emission of Air Contaminants
Detrimental to Person or Property," State of Rhode Island (July 19, 1977).
F. "Air Pollution Control Regulation No.9 - Approval to Construct, Install,
Modify, or Operate," State of Rhode Island (Much 28, 1988).
G. .. Air Pollution Control Regulation No. 15 - Control of Organic Solvent
Emissions," State of Rhode Island (December 10, 1989).
H. "Air Pollution Control Regulation No. 17 - Odors," State of Rhode Island
(February 22, 1977).
L "Air Pollution Control Regulations No. 22 - Air Toxics," State of Rhode
Island (November 22, 1989). " " " "
W~
J. "Chapter 12 - Water Pollution."
K. "Water Quality Regulations for Water Pollution Control," State of Rhode
Isbmd (May 21,1984).
Groundwater
L. "Chapter 13 - Groundwater Protection."
M. "A Summary of Groundwater Classification - Draft," State of Rhode
Island (January 1990). "
Wetlands
- .
N. "Preliminary Detennination Application - Freshwater Wetlands Application
Package," State of Rhode Island.
O. Letter from the State of Rhode Island concerning the attached compilation
of roles and regulations governing the enforcement of the "Fresh Water
Wetlands Act."
P. Letter from W. Edward Wood, State of Rhode Island to Robert F. Bums,
Secretary of the State of Rhode Island (March 9, 1981). Concerning the
enclosed ''Rules and Regulations Governing the Enforcement of the Fresh
W~ Wetlands Act."
3.6 Remedial Investigation (RI) Reports
Reports
1.
2.
"Draft Groundwater Remedial Investigation," Olin Corporation (June 1989).
"Draft Groundwater Remedial Investigaq.on Report - Appendices," Olin
Corporation (June 1989).
The maps associaled with the records cited tIS entries numbered 3 through 6 are
oversized and may be reviewed, by appointment only, at EPA Region /, Boston,
Massachusetts .
3.
4.
"Draft Groundwater Remedial Investigation Report," Olin Corporation
(February 1990).
''Draft Groundwater Remedial Investigation Report - Appendices A-M," Olin
-------
Page 12. .
3.6 Remedial Investigation (RI) Reports (cont'd.)
Reports (cont'd.)
5.. . "Draft Groundwater Remedial Investigation Report - Appendices N-U," Olin
COrporation (February 1990).
EJ. ''Draft Groundwata' Remedial Investigation Report - Appendices AA-AE," Olin
Corporation (February 1990).
- 7. "Draft Groundwater Remedial Investigation Report," Olin Corporation
(June 1990). .
8. ''Draft Groundwater Remedial Investigation Report - Partial Appendices," Olin
Corporation (June 1990).
9. "Addendum Report to Groundwater Remedial Investigation (GRI)," BCM
Engjneers, Inc. for Olin Corporation (October 1990).
The maps associated with the records cited as entries numbered 10 through 13 are
oversized and may be reviewed, by appointment only, at EP A Region I, Boston,
Massachusetts .
10. "Groundwater Remedial Investigation - Text," Olin Corporation
(June 1990).
11. "Groundwater Remedial Investigation - Appendices A-M," Olin Corporation
(June 1990).
12. "Groundwater Remedial Investigation - Appendices N-U," Olin Corporation
(June 1990). .
13. "Groundwater Remedial Investigation - Appendices AA-AF," Olin Corporation.
(June 1990).
14. "Groundwater Remedial Investigation Report - Addendum," EP A Region I
(November 1990).
Comments
15. Comments Dated October 19, 1989 from Lynne A. Fratus, EPA Region I on the
June 1989 "Draft Groundwater Remedial Investigation," Olin Corporation.
16. Comments Dated March 30, 1990 from Lynne A. Fratus, EP A Region I on the
February 1990 "Draft Groundwater Remedial Investigation Report," Olin
Corporation. .
17. Comments Dated April 9, 1990 from Wazren S. Angell n, State of Rhode Island
Department of Environmental Management on the February 1990 "Draft
Groundwater Remedial Investigation Report," Olin Corporation.
18. Comments Dated May 3, 1990 from Wazren S. Angell n, State of Rhode Island
Department of Environmental Management on the February 1990 "Draft
Groundwater Remedial Investigation Report," Olin Corporation.
19. Comments Dated July 24,1990 from Warren S. Angell IT, State of Rhode Island
Department of Environmental Management on the June 1990 "Groundwater
Remedial Investigation Report," Olin Corporation.
20. Comments Dated September 10, 1990 from Warren S. Angell n, State of Rhode
Island Department of Environmental Management on the June 1990
"Groundwater Remedial Investigation Report," Olin Corporation.
21. Comments Dated October 22,1990 from Warren S. Angell n, State of Rhode
Island Department of Environmental Management on the June 1990
-------
Page 13-
3.6 Remedial Investigation (RI) Reports (cont'd.)
Responses to Comments
v
22. -Response Dated November 10, 1989 from John C. Brown, Olin Corporation to
the October 19, 1989 Comments from Lynne A. Fratus, EPA Region I.
....23. Response from Olin Corporation to the October 19, 1989 Comments from
Lynne A. Fratus, EP A Region L
- 24. Response Dated February 26, 1990 from Olin Corporation to the
October 20, 1989, February 13 and February 22, 1990 Comments from Lynne
A. Fratus, EP A Region 1.
25. Response from Olin Corporation to the March 30, 1990 Comments from Lynne
A. Fratus, EP A Region I on the February 1990 "Draft Groundwater Remedial
Investigation Report," Olin Corporation.
26. Response from Olin Corporation to the April 9, 1990 Comments from Wanen
S. Angell n, State of Rhode Island Department of Environmental Management
on the February 1990 "Draft Groundwater Remedial Investigation Report," Olin
Corporation. .
27. Response from Olin Corporation to the May 3,1990 Comments from Warren S.
Angell n, State of Rhode Island Department of Environmental Management on
the February 1990 "Draft Groundwater Remedial Investigation Report," Olin
Corporation.
3.7 Work Pians and Progress Reports
Reports
1. "Draft - Work Plan for Groundwater Remedial Investigation and Feasibility
Study,' 1 Olin Corporation (February 1986). .
2. "Work Plan for Groundwater Remedial Investigation and Feasibility Study," Olin
Corporation (June 1987).
3. Progress Report, Olin Corporation (April 1, 1988).
4. Progress Report, Olin Corporation (May 1, 1988).
5. Progress Report, Olin Corporation (June 1, 1988).
6. Progress Report, Olin Corporation (July 1, 1988).
7. Progress Report, Olin Corporation (August 1, 1988).
8. Progress Report, Olin Corporation (September 1, 1988).
9. Progress Report, Olin Corporation (October 1, 1988).
U). Progress Report, Olin Corporation (November 1, 1988).
. 11. 'Pro~ss Report, Olin Corporation (December 1, 1988).
12. Progress Report, Olin Corporation (January 1, 1989).
13. Progress Report, Olin Corporation (February 1, 1989).
14. Progress Report, Olin Corporation (March 1, 1989).
15. Progress Report, Olin Corporation (April 1, 1989).
16. Progress Report, Olin Corporation (May 1,1989).
17. Progress Report, Olin Corporation (June 1, 1989).
18. Progress Report, Olin Corporation (July 1, 1989).
19. Progress Report, Olin Corporation (August 1, 1989).
20. Progress Report, Olin Corporation (September 1, 1989).
21. Progress Report, Olin Corporation (October 1,1989).
22. Progress Report, Olin Corporation (November 1, 1989).
23. Progress Report, Olin Corporation (December 1, 1989).
24. Progress Report, Olin Corporation (January 1, 1990).
25. Progress Report, Olin Corporation (February 1, 1990).
26. Progress Report, Olin Corporation (March 1, 1990).
27. Progress Report, Olin Corporation (April 1, 1990).
-------
Page 14
3.7 Work Plans and Progress Reports (cont'd)
Reports (cont'd)
29. - Progress Report, Olin Corporation (Iune 5, 1990).
30. Progress Report, Olin Corporation (Iuly 2,1990).
..'31. Pro.gress Report, Olin CorPoration (August 1,1990).
32. Progress Report, Olin Corporation (September 1, 1990).
. 33. Progress Report, Olin Corporation (October 1, 1990).
34. Progress Report, Olin Corporation (November 1, 1990).
35. Progress Report, Olin Corporation (December 1, 1990).
36. Progress Report, Olin Corporation (Ianuary 1, 1991).
37. Progress Report, Olin Corporation (February 1, 1991).
38. Progress Report, Olin Corporation (March 1, 1991).
Comments
39. Letter from Iohn W. Gallagher, EPA Region I to Verrill M NOlWood Ir., Olin
Corporation (April 14, 1986) with attached:
A. "Preliminary Review of Olin Workplans Site Cosure and Groundwater
Study," Olin Corporation.
B. Attendance List, EP A Region I, Rhode Island Department of Environmental
Management, and Olin Corporation (April 1, 1986).
40. Letter from Iohn W. Gallagher, EPA Region I to Verrill M. NOlWood Ir., Olin
Corporation (April 14, 1986) with attached comments on Olin Corporation's job
safety plans for site closure and groundwater study. .
41. Comments Dated December 31, 1987 from Lynne A. Fratus, EPA Region I on the
February 1986 "Work Plan for Groundwater Remedial Investigation and
Feasibility Study," Olin Corporation.
Responses to Comments
42. Response Dated May 14, 1986 from lames C. Brown, Olin Corporation to the
April 14, 1986 Comments from Iohn W. Gallagher, EPA Region I.
43. Response Dated May 29, 1986 from Iohn W. Gallagher, EPA Region I to the
May 15,1986 Response from lames C. Brown, Olin Corporation.
44. Response dated Iuly 23, 1986 from lames C. Brown, Olin Corporation to the
May 29,1986 Comments from Iohn W. Gallagher, EPA Region I.
4.0
Feasibility Study (FS)
4.1 Correspondence
Agency for Toxic Substances and Disease Registry (A TSDR)
1.
Letter from Lynne A Fratus, EP A Region I to Louise House, Agency for Toxic
Substances and Disease RegisDy (ATSDR) (February 4,1991). Concerning an
update of activities at the site and transmittal of the addenda to the Remedial
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Page 15 .
4.1 Correspondence (cont'd.)
BCM Engineers, Inc.
2. - Letter from Roy C. Peterson, BCM Engineers, Inc. to Lynne A. Fratus, EP A
Region I (May 8, 1990). Concerning tranSmittal of the attached:
A. -Cross-Reference: ''Draft Groundwater Feasibility Study Report -. .
Volume 1," Olin Corporation (May 1990) [Flled and cited as entry number
2 in 4.6 Feasibility Study (FS) Reports].
B. Cross-Reference: "Draft Groundwater Feasibility Study Report -
Volume 11," Olin Corporation (May 1990) [Flled and cited as entry number
3 in 4.6 Feasibility Study (FS) Reports].
3. Letter from Roy C. Peterson, BCM Engineers, Inc. to Lynne A. Fratus, EP A
Region I (October 12, 1990). Concerning the tranSmittal of the following
attachments:
A. Cross-Reference: "Groundwater Feasibility Study - Volume 1," BCM
EngiDeers, Inc. for Olin Corporation (October 1990) [Flled and cited as
entry number 4 in 4.6 Feasibility Study (FS) Reports].
B. Cross-Reference: "Groundwater Feasibility Study - Volume 11," BCM
£ngineers, Inc. for Olin Corporation (October 1990) [Filed and cited as
entJy number 5 in 4.6 Feasibility Study (FS) Reports].
C. Cross-Reference: "Groundwater Feasibility Study - Volume m," BCM
Engineers, Inc. for Olin Corporation (October 1990) {Filed and cited as
entry number 6 in 4.6 Feasibility Study (FS) Reports].
Olin Corporation
4. Letter from David 1... Cummings, Olin Corporation to Lynne A. Fratus, EP A
Region I and Warren S. Angell n, State of Rhode Island Departtnent of .
, Environmental Management (February 1, 1990). Concerning transmittal of the
attaChed progress report and Feasibility Study schedule.
S. Letta' from Lynne A. Fratus, EP A Region I to David 1... Cummings, Olin
Corporation (February 23, 1990). Concerning revisions to the Feasibility Study
schedule.
6. Letter from Lynne A.. Fratus, EP A Region I to Robert D. McCaleb, Olin
Corporation (April 17, 1990). Concerning the need for a section in the
Feasibility Study addressing the potential for development of the affected area.
7. I:-ettcr from Robert D. McCaleb for David 1... Cummings, Olin Corporation to
Lynne A. Fratus, EP A Region I (May 8, 1990). Concerning notification that the
February 26,1990 "Initial Screening of Technologies and Process Options,"
BCM Engineers, Inc. for Olin Corporation and the March 23, 1990" Alternative
Screening Results," BCM Engineers, Inc. for Olin Corporation have been
clarified and incorporated into the May 1990 ''Draft Feasibility Study Report,"
Olin Corporation.
8. Letter from Robert D. McCaleb and David 1... Cummings, Olin Corporation to
Lynne A. Fratus, EPA Region I and Warren S. Angell n, State of Rhode Island
Department of Environmental Management (July 10, 1990). Concerning a
summary of the June 28, 1990 meeting and a request for a project schedule
extension.
9. Letter from Robert D. McCaleb and David 1... Cummings, Olin Corporation to
Lynne A. Fratus, EPA Region I and Warren S. Angell n, State of Rhode Island
Department of Environmental Management (July 26, 1990). Concerning a
revised project schedule for the groundwater model
10. Letter from Lynne A. Fratus, EPA Region I to David 1... Cummings, Olin
Corporation (August 24, 1990). Concerning notification that Olin Corporation
is in violation of the Consent Decree for not submitting a revised "Groundwater
-------
.
Page 16
4.1 Correspondence (cont'd.)
Qlin- C9JP0I'8tion (cont'd.)
..' 11. Letter from David L. Cummings, Olin Corporation to Lynne A.lFratus, EP A
Region I (September4,1990). Conceming Olin Corporation'sTeSponse to
EPA's notification that.Olin is in nOD-compH~ with the Consent Decree.
12. Memorandum from Robert D. McCa1eb, Olin Corporation to Lynne A. Fratus,
EPA Region I (December 12, 1990). Concerning tr.msmittal of the attached
BCM Engineers acreage estimates.
13. Memorandum from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus,
EP A Region I (December 14, 1990). Concerning transmittal oCthe attached
description of the modeling scenarios.
14. Letter from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus, EP A
Region I (January 7, 1991). Conceming calculaUons of contaminant mass in the
aquifer. .
15. Letter from Robert D. McCaleb and David L. Cummings, Olin Corporation to
Lynne A. Fratus, EPA Region I (January 7,1991). Concerning transmittal of
the attached revisions and expansions to the October 1990 Feasibility Study'
alternatives. .
16. Letter from Robert D. McCaleb and David L. Cummings, Olin Corporation to
Lynne A. Fratus, EP A Region I (January 22, 1991). Concerning transmittal of
the attached "Revised Cost Estimates." .
17. Memorandum from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus,-
EPA Region I (January 23, 1991). Concerning calculations of the contaminant
mass in the aquifer. .
18. Memorandum from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus,'
EPA Region I (January 23,1991). Concerning acreage estimates.
19. Memorandum from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus,
~.EPA Region I (January 23, 1991). Concerning transmittal of the attached
revised figures for the Feasibility Study. .
20. Letter from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus, EP A
Region I (January 23, 1991). Conceming transmittal of the attached calculations
of contaminant mass in the aquifer. '
21. Letter from Richard C. Boynton, EPA Region I to David L. Cummings, Olin
Corporation (February 4, 1991). Concem1ng transmittal of the February 1991
"Groundwater Feasibility Study Report - AddenduJn," EP A Region I and the
Proposed Plan for the site cleanup. .
22. Letter from Lynne A Fratus, EP A Region I to David L. Cummings, Olin
Corporation (March 15, 1991). Concerning transmittal of the requested
comments submitted to EP A Region Ion the Proposed Plan for the site cleanup
by the State of Rhode Island Dtpartmcnt of EnvUoDmCntal Management
State of Rhode Island Department of Environmental Management
23. Memorandum from Lynne A Fratus, EPA Region I to State of Rhode Island
Department of Environmental Management staff (December 5, 1990).
Concerning a briefing on the proposed plan for the site.
24. Letter from Richard-C. Boynton, EP A Region I to Alicia M. Good, State of
Rhode Island Department ofEnvironmenta1 Management (January 4, 1991).
Concerning the Draft Addendum to the Groundwater Feasibility Study Report.
25. Letter from Lynne A. Fratus for Richard C. Boynton, EPA Region I to Alicia M.
Good, State of Rhode Island Department of Environmental Management
(January 9,1991). Concerning transmittal of Appendix A of the Feasibility
-------
Page 17-
4.1 Correspondence (cont'd.)
State of Rhode Island Department of Environmental Management (cont'd)
26. - Letter from Lynne A. Fratus for Richard C. Boynton, EP A Region I to Alicia M.
Good, State of Rhode Island Department of Environmental Management
(January 22, 1991). Concerning 1raDSmittal of a draft of the Feasibility Study
Report Addendum for review.
- 27. Letter from Richard C. Boynton, EP A Region I to Alicia M. Good, State of
Rhode IslaDd Department of Environmental Management (Febnwy 4, 1991).
Concerning transmittal of the Febnwy 1991 "Groundwater Feasibility Study
Report - Addendum," EP A Region I and the Proposed Plan for the site cleanup.
28. Letter from Lynne A. Fratus, EP A Region I to Susan Kiernan, State of Rhode
Island Department of Environmental Management (FebroaIy 28, 1991).
Concerning potential applicable or relevant and appropriate requirements
Jegarding the site. .
.
,..
'"
4.4 Interim Deliverables
Reports
"Summary, Remedial Objectives, and Potential Technologies for Remediation,"
Olin Corporation (FebnlaIy 8, 1990). .
"Initial Screening of Technologies and Process Options," BCM Engineers, Inc.
for Olin Corporation (FebnlaIy 26, 1990).
"Alternative Screening Results," BCM Engineers, Inc. for Olin Corporation -
(March 23, 1990).
Comments.
1.
2.
3.
Comments Dated February 13, 1990 from Lynne A. Fratus, EPA Region I on
the FebroaIy 8,1990 "Summary, Remedial Objectives, and Potential
Technologies for Remediation," Olin Corporation.
Comments Dated February.22, 1990 from Lynne A. Fratus, EPA Region I on
the FebroaIy 8,1990 "Summary, Remedial Objectives, and Potential
Technologies for Remediation," Olin Corporation.
Comments Dated March 14, 1990 from L~e A. Fratus, EP A Region I on the
FebnlaIy 26, 1990 "Initial Screening of Teebnologies and Process Options,"
BCM Engineers, Inc. for Olin Corporation.
Comments Dated April 10, 1990 from Lynne A. Fratus, EP A Region I on the
March 23,1990 "Alternative Screening Results," BCM Engineers, Inc. for Olin
Corporation. .
Responses to Comments
4.
s.
6.
7.
8.
Letter from David L Cummings, Olin Corporation to Lynne A. Fratus, EP A
Region I and Warren S. Angell n, State of Rhode Island Department of
Environmental Management (February 27, 1990). Concerning transmittal of the
~1V'Jti.
A. Response from Olin Corporation to the FebnlaIy 13,1990 Comments
from Lynne A. Fratus, EPA Region I.
B. . Response from Olin Corporation to the Febnwy 22, 1990 Comments
-------
.
Page 18
4.4 Interim Deliverables (cont'd.)
Responses to Comments (cont'd.)
..
9.
Letter from David L. Cummings, Olin Corporation to Lynne A. Fratus, EP A
Re~on I (May 21,1990). Concerning transmittal of the attached:
A. Response from Olin Corporation to the March 14, 1990 Comments from
Lynne A. Fratus, EPA Region I.
B. Response from Olin Corporation to the April 10, 1990 Comments from
Lynne A. Fratus, EPA Region I.
4.~ Feasibility Study (FS) Reports
Reports
1.
2.
"Draft Focused Feasibility Study Report - Task 3 - Pennanent Water Supply
Study," Camp Dresser & McKee Inc. (October 1985).
"Draft Groundwater Feasibility Study Report - Volume 1," Olin Corporation
(May 1990).
"Draft Groundwater Feasibility Study Report - Volume n," Olin Corporation
(May 1990).
"Groundwater Feasibility Study - Volume I," BCM Engineers, Inc. for Olin
Corporation (October 1990).
"Groundwater Feasibility Study - Volume 11," BCM Engineers, Inc. for Olin .
Corporation (October 1990).
"Groundwater Feasibility Study - Volume m," BCM Engineers, Inc. for Olin
Corporation (October 1990).
"Groundwater Feasibility Study Report - Addendum," EP A Region I
(February 1991).
3.
4.
5.
6.
7.
. .
Comments
8. Comments Dated June 13, 1990 from Lynne A. Fratus, EPA Region Ion the
May 1990 "Draft Groundwater Feasibility Study Rcport," Olin Corporation.
9. Comments Dated June 14, 1990 from Wmen S. Angell n, State of Rhode
Island Department of Environmental Management on the May 1990 "Draft
Groundwater Feasibility Study Report," Olin Corporation.
10. Comments Dated July 16, 1990 from Alicia M Good, State of Rhode Island
. . ,DepClrtment of Environmental Management on the May 1990 "Draft
Groundwater Feasibility Study Report," Olin Corporation.
11. Comments Dated January 10, 1991 from Lynne A. Fratus, EPA Region Ion the
October 1990 "Groundwater Feasibility Study," BCM Engineers, Inc. for Olin
Corporation.
Responses to Comments
12. Response Dated October 22, 1990 from David L. Cummings, Olin Corporation
10 the June 13, 1990 Comments from Lynne A. Fratus, EPA Region I and the
June 14,1990 Comments from Warren S. Angell n, State of Rhode Island
Department of Environmcntal Management
4.9 Proposed Plans for Selected Remedial Action
1.
''EP A Proposes Cleanup Plan to Address Groundwater Contamination at the
-------
.t'age l'j.
Record of Decision (ROD)
5.1 Correspondence
Letter from James W. Fester, State of Rhode Island Department of
EnVironmental Management to Merrill S. Hohman, EP A Region I
(March 11, 1991). Concerning a request for a 60 day extension to the comment
period on the Proposed Plan.
Letter from Merrill S. Hohman, EPA Region I to James W. Fester, State of
Rhode Island Department of Environmental Management (March 13, 1991).
Concerning the response to the March 11, 1991 letter and the denial of an
extension to the comment period on the Proposed Plan.
Letter from Meni11 S. Hohman, EP A Region I to Thomas D. Getz, State of
Rhode Island Department of Environmental Management (March 25, 1991).
Concerning transmittal of the "Draft Record of Decision" for review and
confmnation of the State of Rhode Island's position on the Proposed Plan.
Letter from Merrill S. Hohman, EP A Region I to Thomas D. Getz, State of
Rhode Island Department of Environmental Management (March 27, 1991).
Concerning the response to the March 13, 1991 letter regarding the Groundwater
Protection Act
Letter from James W. Fester, State of Rhode Island Department of
Environmental Management to Merrill S. Hohman, EPA Region I
(March 28, 1991). Concerning a request for additional time to review the Draft
Record of Decision.
Letter from Meni11 S. Hohman, EPA Region I to James W. Fester, State of
Rhode Island Department of Environmental Management (March 29, 1991).
Concerning the response to the March 28,1991 request for additional time to .
review the Draft Record of Decision. .
Facsimile from Louise Durfee, State of Rhode Island Department of
Environmental Management to Julie Belaga, EP A Region I
(Apri112, 1991). Concerning comments on the Draft Record of Decision and
nonconcurrence.
Letter from Julie Belaga, EP A Region I to Louise Durfee, State of Rhode Island
Department of Environmental Management (April 16, 1991). Concerning the
response to the April 12, 1991 facsimile regarding comments on the Draft
Record of Decision.
5.3 Responsiveness Summary
5.0
...1.
'-0
Sp _of Rhode Island Department of Environmental Management
2.
3.
4.
5.
6.
7.
8.
Cross Ref~ce: Responsiveness Summary is an attachment to the
Apri116, 1991 ''Record of Decision;t EPA Region I [Filed and cited as entry
number 1 in 5.4 Record of Decision (ROD)).
TM following citations indicate documents received by EP A Region 1 during the
formol public comment period.
1.
2.
3.
Comments Dated February 28, 1991 from Ethel M. Halsey on the
February 1991 Proposed PJ..an. .
Comments Dated Febnwy 28, 199 i from the State of Rhode Island Department
of Environmental Management on the February 1991 Proposed Plan.
Comments Dated March 11, 1991 from Richard E. Kyte Jr. (Attorney for
Nasonville Water District) on the February 1991 Proposed Plan with the attached
Comments Dated February 26,1991 from George R. Allan, Dufresne-Henry,
Inc.
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.
Page 20
5.3 Responsiveness Summary (cont'd)
5. Comments Dated March 13, 1991 from David L. Cummings, Olin Chemicals on
.~ _the February 1991 Proposed Plan.
6. Comments Dated March 13, 1991 from Thomas D. Getz, State of Rhode Island
Department of Environmental Management on the February 1991 Proposed
Plan.
- 7. Comments Dated ~h 15,1991 from Warren S. Angell n, State of Rhode
Island Department of Environmental Management on the February 1991
Proposed Plan. .
5.4 Record of Decision (ROD)
1.
"Record of Decision," EPA Region I (April 16, 1991) with the attached
Responsiveness Summary, State of Rhode Island NonconcUITence Letter, and
the Administrative Record Index. .
6.0
Remedial Design (RD)
6.1 Correspondence
Nasonville Water District
1. Letter from Felix Harvey, State of Rhode Island Department of Environmental
Management to Maria f1anagan, Nasonville Water District
(September 26, 1986). Concerning location of storage tank.
2. Letter from Felix Harvey, State of Rhode Island Department of Environmental
Management to Maria flanagan, Nasonville Water District (October 15, 1986). .
Concerning agreement on the location of the storage tank.
3. Letter from John W. Gallagher, EPA Region I to Maria Flanagan, Nasonville
..Water District (October 15, 1986). Concerning construction of the water line.
. 4.. Letter from David E. Pinsky, Camp Dresser & McKee Inc. to John Hagopian,
State of Rhode Island Department of Health (June 3, 1987). Concerning design
considerations for the proposed well field at Site E.
5. Letter from John W. Gallagher, EPA Region I to Ethel W. Halsey, Nasonville
Water District (June 12, 1987). Concerning status on worlc begun as ordered by
Consent Decree. .
6. Letter from Warren S. Angell n, State of Rhode Island Department of
Environmental Management to Ethel M. Halsey, Nasonville Wate!' District
(June 3,1988). Concerning progress at the site.
7. . Letter from Warren S. Angell n, State of Rhode Island Department of
Environmental Management to Ethel M. Halsey, Nasonville Water District
(June 3, 1988). Concerning progress of issues listed on the proposed
June 7, 1988 Nasonville Water District meetiJ:tg agenda.
8. Letter from Warren S. Angell n, State of Rhode Island Department of
Environmental Management to Ethel M. Halsey, Nasonville Water District
(September 13, 1988) with attached Letter from Peter P. Calise, State of Rhode
Is1and Water Resources Board to Warren S. Angell n, State of Rhode Island
Department of Environmental Management (June 9,1988). Concerning the
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'--
Page ~ 1
6.1 Correspondence (cont'd.)
, Nasonvillc Water Disttict (cont'd.)
.'
." 9. - Memorandum from Ethel M. Halsey, Nasonville Water Disttict to Lynne A.
..' Fratus, EPA Region I (September 22, 1988) with attached:
A. Memorandum from Ethel M. Halsey, Nasonville Water Disttict to Nasonville
Water Disttict ~ Members (September 21, 1988). Concerning the lack of
progress at the site.
B. Letter from Peter P. Calise, State of Rhode Island Water Resources Board to
Warren S. Angell n, State of Rhode Island Department of Environmental
Management (June 9, 1988). Concerning the approval of the application for a
new water supply source.
C. Letter from Irene Winkler, U.S. Department of Agriculture to Ethel M.
Halsey, Nasonville Water District (August 31, 1988). Concerning the
installation of a public water line. '
10. Letter from Lynne A. Fratus, EPA Region I to Warren S. Angell n, State of
Rhode Island Department of Environmental Management (October 24, 1988).
Concerning response to the attached October 3, 1988 Letter from Nasonville Water
District
11. Letter from W men S. Angell II, State of Rhode Island Department of
Environmental Management to Ethel M. Halsey, Nasonville Watr.r Disttict
(November 25, 1988). Concerning response to the October 3, 1988 Letter from
Nasonville Water District.
12. Letter from Ethel M. Halsey, Nasonville Water District to Warren S. Angell If,
State of Rhode Island Department of Environmental Management
(December 21, 1988). Concerning the attached compilation of questions, answers
and comments on progress at the site.
13. Letter from W men S. Angell n, State of Rhode Island Department of
Environmental Management to Ethel M. Halsey, Nasonville Water District
(February 22, 1989). Concerning Nasonville Water District water main.
14. Letter from Mary E. Kay, State of Rhode Island Department of Environmental
Management to Francis A. Gaschen (Attorney for the Nasonville Water District)
(March 27,1989). Concerning parcels of real estate needed for construction of a
water line in the Nasonville Water District.
15. Letter from Lynne A. Fratus, EPA Region I to Ethel M. Halsey, Nasonville Water
District (March 27,1989). Concerning the attached estimated schedule for
construction of water line.
16. Letter from Lynne A. Fratus, EPA Region I to Warren S. Angell n, State of
Rhode Island Department of Environmental Management (March 29, 1989) with
attached~. Concerning description of the affected area at the site.
17. Letter from W men S. Angell n, State of Rhode Island Department of
Environmental Management to Maria Flanagan, Nasonville Water District
(lune 6, 1989). Concerning transmittal of correspondence from U.S. Army
Corps of Engineers pertaining to construction of a water line.
Miscellaneous
18. Memorandum from Robert P. Hartley, EPA Headquarters to File
. (January 13, 1987). Concerning summary of meeting with representatives of
American Colloid Company.
19. Letter from Paul P. Ozarowski and Wesley E. Stimpson, Haley & Aldrich, Inc. to
Thomas E. Taylor, Weston Services, Incorporated (July 28, 1987). Concerning
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.
Page 22
6.3 Applicable or Relevant and Appropriate Requirements (ARARs).
1.- Letter from Felix Harvey, State of Rhode Island Department of Environmental
.. -Management to Venill M Norwood Jr., Olin Corporation (April 22, 1986).
Concerning the attached "Regulations for Underground Storage Facilities Used
foN»etroleum Products and Hazardous Materials," State of Rhode Island
Department of Environmental Management.. .
6.4 Remedial Design Documents
The record cited in e1llry number 1 is an oversized document and may be reviewed, by
appointment only, at EPA Region I, Boston, Massachusetts.
"Permanent Water Supply, Western Sand and Gravel Superfund Site, Final
Engineering Plans," Sea Consultants, Inc. (January 1988).
Letter from Mary E. Kay, State of Rhode Island Department of Environmental
Management to Lynne A. Fratus, EPA Region I (April 12, 1989). Concerning
transmittal of the attached "Statement of Condemnation of Fee Title and
ConstJUction and Maintenance Easements," State of Rhode Island Department of -
Environmental Management. (March 29,1989).
Plans associated with rhe records cited in e1llry numbers 3 and 6 may be reviewed, by
appointment only, at EPA Region I, Boston, Massachusetts.
1.
2.
3.
"Plans and Specifications (ForConstJUction Contract) Western Sand & Gravel-
Superfund Site Permanent Water Supply," U.S. Army Corps of Engineers
(May 1989).
"Amendment No. 0001 to Specifications and Drawings for ConstJUction of
Western Sand and Gravel Superfund Site, Permanent Water Supply, Bunillville,
..iRhode Island," U.S. Army Corps of Engineers (May 17, 1989).
. "Amendment No. 0002 to Specifications and Drawings for ConstJUction of
Western Sand and Gravel Superfund Site, Permanent Water Supply, Bunillville,
Rhode Island," U.S. Army Corps of Engineers (June 28, 1989).
"Amendment No. 0003 to Specifications and Drawings for ConstJUction of
Western Sand and Gravel Superfund Site, Permanent Water Supply, Bunillville,
Rhode Island," U.S. Army Corps of Engineers (July 12, 1989).
"Amendment No. 0004 to Specifications and Drawings for ConstJUction of
Western Sand and Gravel Superfund Site, Permanent Water Supply, Bunillville,
Rhode Island," U.S. Army Corps of Engineers (July 21, 1989).
4.
s.
6.
7.
The record cited in e1llry number 8 is an oversized document and may be reviewed, by
appointment only, at EPA Region I, Boston, Massachusetts.
8.
Letter from State of Rhode Island Department of Environmental Management
(July 24, 1989). Concerning transmittal of the attached final signed easement
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Page 23 .
Remedial Action (RA)
7.1 Correspondence
.
NasoDville Water District
,.i. Le~ from Lyune A. Fratus, EP A Region I to William Flanagan, Nasonville
Water District (November 7, 1989). Concerning the status of construction of the
waterline which will service the Nasonville Water District. .
2. Letter from Lynne A. Fratus, EP A Region I to William Flanagan, Nasonville
Water District (December 4, 1989). Concerning EP A's position on future
connections to the waterline.
3. Letter from Lynne A. Fratus, EP A Region I to William Flanagan, Nasonville
Water District (May 9, 1990). Concerning a request that the Nasonville W iter
District finalize the State-Aid Agreement with the State of Rhode Island
Department of Environmental Management as soon as possible.
4. Letter from Lynne A. Fratus, EPA Region I to Richard E. Kytc Jr. .
(August 8, 1990). Concerning the derivation of the estimated operation and
maint.enance costs for the waterline and the attaChed Letter from John Gallagher,
EPA Region I to Felix Harvey, State of Rhode Island Department of
Environmental Management (October 16, 1986).
S. Letter from Richard E. Kyte Jr. to Lynne A. Fratus, EPA Region I
(October 17, 1990). Concerning both the dcsU'e that the roadways serviced by
the waterline should be paved and the attaChed:
A. Letter from Richard E. Kyte Jr. to Oaude Cote, State of Rhode Island
Department of Environmental Management (October 17, 1990). -
B. Letter from George R. Allen, Dufresne-Henry, Inc. to William Flanagan,
N asonville Water District (September 28, 1990).
C. Letter Report from David L. Merithew, Robert L. Merithew, Inc. to
George R. Allen, Dufresne-Henry, Inc. (September 26, 1990).
Concerning the September 5, 1990 inspection of the 100,000 gallon water
sphere located within the Nasonville Water District.
6. Letter from Richard E. Kyte Jr. (Attorney for Nasonville Water District)
(December 6, 1990). Concerning transmittal of the attaChed Letter from Michael
E. Grilli, Beta Engineering, Inc. to William Flanagan, Nasonville Water District
(October 26,1990) regarding paving the roads.
7. Letter from Richard E. Kyte Jr. (Attorney for Nasonville Water District) to
Lynne A. Fratus, EPA Region I (February 13,1991). Concerning the request
for specific cost infonnation regarding the site cleanup.
S. ., Letter from Thomas Bercher, Town of Bunillville to William Flanagan,
Nisonville Water District (February 21, 1991). Con~g the inadequate
reconstruction of Gig and Pulaski Roads.
9. Letter from Lynne A. Fratus, EPA Region I to William Flanagan, Nasonville
Wattt District (February 21, 1991). Concerning transmittal of the infonnation
requested on EP A's decision to not pave the roads over the water system.
10. Letter from Richard E. Kyte Jr. (Attorney for Nasonville Water District) to
Lynne A. Fratus, BfA Region I (March 13, 1991). Concerning the request for
cleanup cost figures.
11. Letter from Lynne A. Fratus, EP A Region I to Richard E. Kyte Jr. (Attorney for
Nasonville Watt:rDistrict) (March 20, 1991). Con~g a 1'q)ly to the request
-------
7.1 Correspondence (cont'd.)
Olin COIpOr'ation
Page 24 .
12. - Letter from Iohn W. Gallagher, EP A Region I to lames C. Brown, Olin
Corporation (August 22, 1986). Concerning Bentonite-enhanced layer.
..' 13. LettCr from lames C. Brown, Olin Corporation to John W. Gallagher, EPA
Region I (September 29, 1986). Concerning the Bentonite-enhanced soil layer
of the cap. .
14. Letter from John W. Gallagher, EPA Region I to Venill M. Norwood Jr., Olin
Corporation (May 21, 1987). Concerning comments on the cover system and its
installation.
15. Letter from John W. Gallagher, EP A Region I to James C. Brown, Olin
Corporation (Iune 9,1987). Concerning summary of plans for the cap.
16. Letter from James C. Brown, Olin CorpOration to John W. Gallagher, EPA
Region I and Felix Harvey, State of Rhode Island Department of Environmental
Management (Iuly 3, 1987). Concerning field permeability testing of the cap.
17. Letter from lames C. Brown, Olin Corporation to Tina Cardi, State of Rhode
Island Department of Environmental Management (July 3, 1987). Concerning
attached Permanent Cosme Application for the underground storage tank located
at the site.
18. Letter from James C. Brown, Olin Corporation to John W. Gallagher, EPA
Region I and Felix Harvey, State of Rhode Island Department of EnvironmentaI
Management (Iuly 13, 1987) with attached map. Concerning sources of
stJUctura1 and frost protection fill materials.
19. Letter from James C. Brown, Olin Corporation to John W. Gallagher, EPA
. Region I (August 4, 1987). Concerning field permeability testing of the cap.
20. Letter from lames C. Brown, Olin Corporation to John W. Gallagher, EPA
Region I and Felix Harvey, State of Rhode Island Department of Environmental
Management (September 9, 1987). Concerning the handling of solid
. contaminated materials at the site.
21. Letter from James C. Brown, Olin Corporation to Peter Sullivan, State of Rhode
Island Department of Environmental Management (October 26, 1987).
Concerning transmittal of photographic documentation of the August 22, 1987
underground storage tank at the site.
22. Letter from lames C. Brown, Olin Corporation to Iohn W. Gallagher, EPA
Region I and Felix Harvey, State of Rhode Island Department of Environmental .
Management (November 2, 1987). Concerning transmittal of report on
laboratory and field test work supporting the final design of Bentonite-enhanced
layer.
23. Letter from James C. Brown, Olin Corporation to John W. Gallagher, EPA
Region I (November 4, 1987). Concerning notes from October 7, 1987
conference call.
24. Letter from lames C. Brown, Olin Corporation to John W. Gallagher, EPA
Region I and Felix Harvey, State of Rhode Island Department of Environmental
Management (December 7, 1987). Concerning seeding of the fenced area at the
site.
25. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin
Corporation (December 8, 1987). Concerning letter from EP A Region I to State
of Rhode Island Departmeut of Env:ronmental Management regarding the
cover's ability to meet RCRA requirements.
26. Letter from Lynne A. Fratus, EPA Region I to James C. Brown, Olin
Corporation (December 28, 1987). Concerning seeding of the cap.
27. Memorandum from Doug G. Harrod, Olin Corporation to Robert D. McCaleb,
Olin Corporation (February 17, 1988). Concerning seeding of the cap.
28. Letter from lames C. Brown, Olin Corporation to Lynne A. Fratus, EPA
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.
Page 25
7.1 Correspondence (cont'd.)
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Page 2t1
7.1 COITespondence (cont'd.)
S.E.A. Consultants Inc. (cont'd.)
49. - Letter from Douglas F. Reed, S.E.A. Consultants Inc. to Lynne A. Fratus, EP A
Region I (September 10,1990). Concerning transmittal of the attached "Draft
W~ Supply and Distribution System Operation and Maintenance Manual,"
Nasonville Wasa- District Board of Water Commissioners (August 1990) for
CODUnenm. .
41. Letter from Douglas F. Reed, S.E.A Consultants Inc. to Lynne A. Fratus, EP A
Region I (October 4, 1990). Concerning response to the State of Rhode Island
Department of Environmental Management's concerns over the watennain size
and material used as well as providing service to Lot 50A and Lot 51.
42. Letter from Douglas F. Reed, S.E.A. Cons~tants Inc. to Lynne A. Fratus, EP A
Region I (December 11, 1990). Concerning the Swface Water Treatment Rule.
43. Letter from Douglas F. Reed, S.E.A. Consultants Inc. to Maurice Beaudoin,
U.S. Army Corps of Engineers (December 12,1990). Concerning responses to
the October 12, 1990 Department of Health concenis with the Nasonville water
system.
44. .Letter from Douglas F. Reed, S.E.A. Consultants Inc. to Maurice Beaudoin,
U.S. Army Corps of Engineers (December 20, 1990). Concerning comments
on the "Scope of Services" for an operator of the Nasonville water system.
. 45. Letter from Douglas F. R=i, S.E.A. Consultants Inc. to Lynne A. Fratus, EP A
Region I (January 15, 1991). Concerning the attached "Evaluation of Impacts of
the Swface water Treatment rule on the Taddin Road Well Site."
46. Letter from Douglas F. Reed, S.E.A. Consultants Inc. to Lynne A. Fratus, EP A
Region I (January 15, 1991). Concerning the attached "Supplemental Response
to RIDOH Comments on Nasonville Water System."
State of Rhode Island Department of Environmental Management
. .
47. Letter from Dennis Huebner for Menill S. Hohman, EPA Region I to Thomas
D. Getz, State of Rhode Island Department of Environmental Management
(November 19, 1987). Concerning comments on the cover's ability to meet
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Page 27
"
7.1 Correspondence (cont'd.)
State of Rhode Is1and Department of Envirorimental Management (cont'd.)
. AS. ~ from Wmen S. Angell n, State of Rhode Island Depal'UDeDt of
. Environmental Management to Lynne A Fratus, EP A Region I
(November 28, 1989). Concerning tranSmittal of the following attaChments:
A. Letter from Dean H. Albro, State of Rhode Island ~t of
Environmental Management to Anthony 1. Zuena, S.E.A Consultants,
Inc. (March 23, 1988). Concerning the review of the request for "Fresh
Watcr Wetland Applicability Determination."
B. Letter from Edgar R. Girard, State of Rhode Island ~nt of Health
to Warren S. Angell n, State of Rhode Island Department of
Envirorimental Management (June 2, 1988). Concerning the attaChed State
of Rhode Island Department of Health's approval for a tubular well field,
pumping station, and 100,000 gallon elevated storage tank to serve the
~ Nasonvillc Water District
C. Letter from Eugene A. Morin, State of Rhode Island Department of Health
to Thomas D. Getz, State of Rhode Island Department of Environmental
Management (June 22, 1987). Concerning the attached State of Rhode
Island Department of Health's approval of a site for the ~ed
development of a well field to serve the proposed Nasonville Water
District
D. Letter from Peter P. Calise, State of Rhode Island Water Resources Board.
to Wmcn S. AngeU n, State of Rhode Island Department of
Environmental Management (June 9, 1988). Concerning the State of
Rhode Island Water Resources Board's recommendations, for the State of .
Rhode Island DepartI1!CDt of Environmental Management
E. "Notice of Proposed Construction or Alteration" Form, U.S. Department
of Transportation Federal Aviation Administration (July 14, 1988).
49. Letter from Lynne A Fratus, EPA Region I to Warren S. Angell n, State of
Rhode Island Department of Environmental Management (April 4, 1990).
Concerning notification that construetion of the waterline has begun and the
attached "News Release," U.S. Army Corps of Engineers (March 19, 1990).
SO. Letter from Menill S. Hohman, EP A Region I to Michael A. Annanllnmo, State
of Rhode Island Department of Environmental Management (May 24, 1990).
Concerning the request that the State of Rhode Island Department of
Environmental Management finalize the State-Aid Agreement with the Nasonville
Water District as soon as possible.
51. Letter from Lynne A Fratus, EPA Region I to Warren S. Angell n, State of
Rhode Island Department of Environmental Management (August 28, 1990).
Concerning comments on the August 31, 1990 ''Draft Rules and Regulations for
the Nasonville W mer District," S.E.A. Consultants, Inc.
52. Letter from Lynne A. Fratus, EPA Region I to Warren S. Angell n, State of
Rhode Island Department ofEnvironmcntal Management (September 4, 1990).
Concerning tranSmittal of the 1984 Rcconi of Decision.
53. Letter from Richard C. Boynton, EP A Region I to Alicia Good, State of Rhode
Island Department of Environmental Management (September 17, 1990).
Concerning the schedule for completing construction of the waterline.
54. Letter from Michael Annarummo, State of Rhode Island Department of
Environmental Management to Julie Bdaga, EP A Region I
(September 18, 1990). Concerning the Superfund State Contract for Remedial
Measures Related to the Site and the Nasonvil1e water system.
55. Letter from Warren S. Angell n, State of Rhode Island ~t of
Environmental Management to Ann Marie Gomes (October 11, 1990).
Concerning tranSmittal of the attaChed "Request for Connection to the EP A
Watel' Distribution System."
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Page 28.
7.1 Correspondence (cont'd)
State of Rhode Island Department of Environmental Management (cont'd)
56. - Letter from Julie Belaga, EP A Region I to Michael Annanunmo, State of Rhode
Island Department of Environmental Management (October 17, 1990).
Co.ocemiDg Superfund State Contract for Renvo.ttill Measures Related to the Site
and the Nasonville water system.
- 57. Letter from Richard C.- Boynton, EP A Region I to Alicia M Good, State of
Rhode Island Department of Environmental Management (November 13, 1990).
Concerning transmittal of the draft scope of services for the operation and
maintenance of the water supply.
58. Letter from Alicia M Good, State of Rhode Island Department of Environmental
Management to Richard C. Boynton, EP A Region I (November 29, 1990).
Concerning an update of the State of Rhode Island's activities at the site.
59. Letter from Thomas D. Getz, State of Rhode Island Department of .
Environmental Management to William Flannagan, Nasonvill~ Water District
(December 4, 1990). Concerning the request of whether or not the Nasonville
Water District is willing to accept operation and maintenance responsibilities for
the water supply system.
60. Letter from Richard C. Boynton, EP A Region I to Alicia M Good, State of
Rhode Island Department of Environmental Management (December 14, 1990).
Concerning response to State of Rhode Island Department of Environmental
Management comments on the waterline.
61. Letter from June Swallow, State of Rhode Island Department of Health to
Richard C. Boynton, EPA Region I (December 14,1990). Concerning
~jmjnaJy determination that the surface water treatment rule will apply to the
Nasonville Water District. .
62. Letter from Lynne A. Fratus, EPA Region I to Wmen S. Angell n, State of .
Rhode Island Department of Environmental Management (December 21, 1990).
Concerning transmittal of a copy of S.E.A. Consultants Inc. 's response to State
of Rhode Island Department of Environmental Management's comments on the
waterline.
63. Letter from Alicia M. Good for Thomas T. Getz, State of Rhode Island
Department of Environmental Management to Merrill S. Hohman, EP A Region I
(December 26,1990). Concerning issues that have come up regarding the site
waterline.
64. Letter from Merrill S. Hohman, EPA Region lto Thomas T. Getz, State of
Rhode Island Department of Environmental Management (February 25, 1991).
, Con~g the status of construction and ownership of the waterline.
U.S. Army Corps of Engineers
65. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Gary D.
Robinson, R.H. White Construction Company, Inc. (November 1,1989).
Concerning the confmnation that a pre-construction conference will be held on
November 6, 1989 to review the contract requirements.
66. Memorandum from Maurice Beaudoin, U.S. Army Corps of Engineers to
Contract Files (November 7, 1989) with the attached Attendance List.
Concerning notes on the November 6, 1989 pre-construction conference.
67. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Gary D.
Robinson, R.R White Construction Company, Inc. (November 8, 1989).
Concerning the confinnation that a public meeting is scheduled for
November 28, 1989.
68. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to the U.S.
Department of Transportation Federal Aviation Administration
(January 18, 1990). Concerning transmittal of the "Notice of Proposed
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~
a
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.
Page 29
7.1 Correspondence (cont'd.)
Q.S. Army Corps of Engineers (cont'd.)
"' 69. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to William
~ Flanagan, Nasonville Waa District (March 1, 1990). Concerning tranSmittal of
the color chart for the paint system for the elevated water storage tank to be
constructed. ".
70. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Gary D.
Robinson, R.H. White Construction Company, Inc. (March 9,1990).
Concerning a request for a price quotation to upsize the proposed pump station
generator exhaust louver.
71. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Susan Frank,
EPA Region I (April 16, 1990). Concerning an update on site activities and
tranSmittal of the attaChed ~ "Schedule of Construction."
72. Letter from Lynne A. Fratus, EP A Region I to Maurice Beaudoin, U.S. Army
Corps of Engineers (March 7, 1990). Concerning changes to be made to the
waterline design.
73. Letter from Anna F. Krasko, EPA Region I to Maurice Beaudoin, u.s. Army
Corps of Engineers (March 27, 1990). Concerning U"ansmittal of the EP A logo
to be posu:d on the construction sign for the site.
74. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Lynne A.
Fratus, EP A Region I (April 23, 1990). Concerning the on-the-ground staking
of the limias of the road easement.
75. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to William
Flanagan, Nasonville Water District (April 26, 1990). Concerning tranSmittal of
the color charts for the paint system for the pump station exterior door and
interior surfaces.
76. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Lynne A.
Fratus, EPA Region I (April 30, 1990). Concerning the following attachments:
A. "Physical Alteration Permit App1icatioo," State of Rhocle Island
Departme1!t of Transportation (April 30, 1990).
B. "Building Permit Application."
C. Letter from James B. Duncan, The Stephen B. Church Company to Herb
Johnston, U.S. Geological Survey (April 19, 1990). Concerning
notification that The Stephen B. Church Company will be testing water
wells on April 23 or April 24, 1990.
D. Letter from James B. Duncan, The Stephen B. Church Company to Sue
Kiernan, State of Rhode Island Departtnent of Environmental Management
(April 19, 1990). Concerning notification that The Stephen B. Church
Company will be testing water wells on April 23 or April 24, 1990.
77. Letter from Lynne A. Fratus, EP A Region I to Maurice Beaudoin, U.S. Army
Corps of Engineers (May 3,1990). Concerning EPA's response to the
April 23, 1990 letter recommending that the limits of the easements for the
w8tcr1ine be physically staked in the field and requesting an updated budget for
the project.
78. Letter from Lynne A. Fratus, EP A Region I to Maurice Beaudoin, U.S. Army
Corps of Engineers (May 18, 1990). Concerning tranSmittal of access
agteements. ",,"
79. Letter from Lynne A. Fratus, EP A Region I to MaUrice Beaudoin and John
Barrett, U.S. Army Corps of Engineers, and Douglas F. Reed, S.E.A.
Consultants Inc. (June 18, 1990). Concerning a request that the "Rules and
Regulations Manual" and the "Operation and Maintenance Manual" be prepared
and submitted to EP A and the State of Rhocle Island Departtnent of
Environmental Management by July 31,1990.
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.
Page 30
7.1 Correspondence (cont'd.)
t}.S.- Anny Corps of Engineers (cont'd.)
. 80. ~ from Maurice Beaudoin, U.S. Anny Corps of Engineers to Gary D.
RGbinson, R.H. White Constnlction Company, Inc. (June 27, 1990).
Concerning a request that the Operation and Maintenance Manuals for the pump
station be submitted to S.E.A. Consultants Inc. as soon as possible.
81. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to Ronald S.
Ponte, S.E.A. Consultants Inc. (July 23, 1990). Concerning transmittal of the
following attached letters:
A. Letter from Gary D. Robinson, R.H. White Construction Company, Inc.
to Maurice Beaudoin, U.S. Anny Corps of Engineers (July 19, 1990).
Concerning submittal of additional cost estimates to provide three phase
power.
B. Letter from Jeffrey T. Palumbo, Blackstone Valley Electric Company to
Dana Johnston, Electrical Associates (June 29, 1990). Concerning utility
charges associated with supplying three phase power to the Nasonville
water pump station.
82. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to Richard Sl
Sauveur, Town of Bunillville Department of Public Works (July 24, 1990).
Concerning the attached diagram of a reinforced concrete collar to be constructed
at all six inch diameter gate valve boxes.
83. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to Douglas F. .
Reed, S.E.A. Consultants Inc. (August 27, 1990). Concerning transmittal of
copies of plan and deed data for the Salvatore DeFelice parcel of land.
84. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to Edgar R.
Girard, State of Rhode Island Department of Health (September 18, 1990).
Concerning transmittal of the following attachments:
A. Letter from Ronald S. Ponte, S.E.A. Consultants Inc. to Maurice
Beaudoin, U.S. Anny Corps of Engineers (July 27, 1990). Concerning
the conclusion that the water samples taken from the newly installed wells
are not representative of the water quality to be seen when the well system
is on line.
B. "Certificate of Analysis," R.I. Analytical.
85. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to Warren S.
Angell IT, State of Rhode Island Department of Environmental Management
(September 21, 1990). Concerning transmittal of a September 18, 1990 letter
from the R.H. White Construction Company, Inc. stating that the watermain
was tested on June 6,1990.
86. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to Lynne A.
Fratus, EPA Region I (September 28, 1990). Concerning a reply to the State of
Rhode Is1and Department of Environmental Management's suggestion that the
water supply system be redesigned and that a protective bituminous concrete
pavement be constructed whezoe watermains were installed.
87. Letter from SL. Carlock, U.S. Anny Corps of Engineers to Lynne A. Fratus,
EPA Region I (September 28, 1990). Concerning the recommendation that
asphalt road swfacing will not SClVe as any extra protection to the buried
waterline.
88. Letter from Maurice Beaudoin, U.S. Anny Corps of Engineers to R.H. White
Constnlction Company, Inc. (September 28,1990). Concerning the pre-fmal
inspection conducted on September 26, 1990 and the attached "Deficient Work
Item List As Of 27 September 1990."
89. Letter from Lynne A. Fratus, EPA Region I to Maurice Beaudoin, U.S. Anny
Corps of Engineers (October 10, 1990). Concerning a request that Plat 43, Lot
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i-age :H. .
7.1 Correspondence (cont'd.)
U.S. Army Corps of Engineers (cont'd.)
-
90. .Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Lynne A.
Fratus, EPA Region I (October 18, 1990). Concerning clarifICation of what is
exp..ccted from the U.S. Army Corps of Engineers under the existing contract.
91. Letter from Lynne A. Fratus, EPA Region I to Maurice Beaudoin, U.S. Army
Corps of Engineers (October 22, 1990). Concerning tranSmittal of a package of
information from the Nasonville Water District for review.
92. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Gary D.
Robinson, R.H. White ConstIUction Company, Inc. (October 25,1990).
Concerning notification that an operator for the water supply system has not yet
been selected by the State of Rhode Island Department of Environmental
Management.
93. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Gary D.
Robinson, R.H. White ConstIUCtion Company, Inc. (October 29, 1990).
Concerning baumlittal of the September 28, 1990 Letter from Dufresne-Hemy,
Inc. and the September 26, 1990 "Inspection Report," Robert L. Merithew, Inc.
94. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Lynne A.
FratDs, EP A Region I (November 1, 1990). Concerning transmittal of the
,ttw-.bcd "Draft Soope of Services for the Operation and Maintenanee of the
Site', Permanent Water Supply Syuem."
95. Letter from Maurice Beaudo~ U.s. Army Corps of Engineers to Douglas F.
Reed, S.E.A. Consultants Inc. (November 9, 1990). Concerning transmittal of
the October 30, 1990 comments on the construction of a permanent water
supply.
96. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to William
Flanagan, Nasonville Water District (November 14, 1990). Concerning
confmnatioo that painting will be conducted from November 14, 1990 to
November 19, 1990.
97. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to Richard St.
Sauveur, Town of Bunillville (December 6, 1990). Concerning transmittal of
one set of half-size prints and As-Builts swing tie infonnation for the waterline.
98. Letter from Maurice Beaudoin, U.S. Army Corps of Engineers to R.H. White
ConstIUction Co., Inc. (December 28, 1990). Concerning transmittal of results
of water sampling.
99. Letter from Lynne A. Fratus, EPA Region I to Maurice Beaudoin, U.S. Army
Corps of Engineers (January 3,1991). Concerning transmittal of a
December 26, 1990 Letter from the State of Rhode Island Department of
Environmental Management for review.
100. Letter from Maurice Beaudoin, U.S. Army Corps of Engineen to Lynne A.
Fratus, EP A Region I (January 18, 1991). Concerning response to comments
from the State of Rhode Island ~t of Environmental Management and
the State of Rhode Island Department of Health.
7.2 Sampling aDd Analysis Data
1. -. "Report on Low Permeability Borrow Material Investigation," Haley & Aldrich,
Inc. for Olin Corporation (August 1986).
2. "Report on Supplemental Laboratory Low Permeability Soil Testing Program,"
Haley & Aldrich, Inc. for Olin Corporation (May 1987).
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7.5 Remedial Action Documents
.
Page 32
Letter from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus" EP A
Region I (August 29,1990). Concerning transmittal of the attached
August 11, 1989 Letter from J.C. Brown, Olin Corporation to Lynne A. FratU6,
EP A Region I and WaITen S. Angell II, State of Rhode Island Department of
Environmental Management as well as the "Site Cosure Survey Plat."
Letter from Richard C. Boynton, EP A Region I to David L. Cummings, Olin .
Corporation (September 18, 1990). Concerning transmittal of EP A Rt::gion I
comments on the August 1989 "Post-Closure and Contingency Plan," Olin
Corporation.
Letter from Lynne A. Fratus for Richard C. Boynton, EP A Region I t<> David L.
Cummings, Olin Corporation (February 8,1991). Concerning clarification of a
comment on the post-closure and contingency plans for the site.
7.6 Work Plans and Progress Reports
The records cited in entries number 1 and 2 may be reviewed, by appointment only, at
EPA_Region 1, Boston, Massachusetts.
..' 1.
2.
''Final Certification Report - Cap Closure: Volume 1 of 2," Golder Associates
for-olin Corporation (April 1988).
"Fmal Certification Report - Cap Cosure: Volume 2 of 2," Golder Associates
for Olin Corporation (April 1988). .
Letter from James C. Brown, Olin Corporation to Lynne A. Fratus, EP A
Region I and WaITeD S. Angell n, State of Rhode Island Department of
Environmental Management (October 6, 1989). Concerning the request for
written approval of site closure construction activities.
Letter from David L. Cummings, Olin Corporation to Lynne A. Fratus, EP A
Region I and WaITeD S. Angell n, State of Rhode Island Department of
Environmental Management (August 20, 1990). Concerning the scheduled dates
for the annual post-closure sampling event at the site and the request for formal
approval of the "Post-Cosure and Contingency Plan."
3.
4.
The map associated with the record cited in entry number 5 is oversized aniJ' may be
reviewed, by appoinlment only, at EPA Region!, Boston, Massachusetts.
s.
6.
7.
1.
Letter from John W. Gallagher, EPA Region I to Robert P. Hartley, EPA
Office of Research and Development (October 6, 1986). Concerning proposal
by Olin Corporation for the clay layer cap at the site.
Letter from James C. Brown, Olin Corporation to John W. Gallagher, EPA
Region I and Felix Harvey, State of Rhode Island Department of Environmental
Management (June 12, 1987). Concerning the attached site closure exhibits:
A. Worlt Plan for Closure and Post-Closure Activities.
B. Pedormance Schedule. .
C. Construction Procedure and Specifications.
D. Groundwater Recirculation System Closeout Details Drawings.
E. Remedial Action/Site Closure.
F. Construction Quality Assurance Plan.
G. Map with Site Location.
H. Names of "Pond Washings" and Other Material Suppliers.
L Monitoring and Pumping Wells to be Closed.
J. Justification for 6 inch Bentonite-Enhanced Soil.
"Permeability Testing for the Western Sand and Gravel Cap," Haley & Aldrich,
Inc. for Olin Corporation (September 1987).
"Quarterly Progress Report No.1," Olin Corporation (October 10, 1987).
"Quarterly Progress Report No.2," Olin Corporation (January 10, 1988).
2.
3.
4.
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Page 31
J
7.6 Work Plans and Progress Reports (cont'd.)
'6. "Quarterly Progress Report No.2, Page 2 of Appendix A," Olin Corporation
(January 12, 1988).
7.' . - "Quar1erly Progress Report No.3," Olin Corporation (April 10, 1988).
8. "Quarterly Progress Report No.4," Olin Corporation (July 10, 1988).
,.,' 9. "Qurterly Progress Report No. 5," Olin Corporation (October 10,1988).
- 10. "Quarterly Progress Report No.6," Olin Corporation (January 10, 1989).
11. "Quarterly Progress Report No.7," Olin Corporation (April 1 0, 1989).
12. "Quarterly Progress Report No.8," Olin Corporation (July 10, 1989).
13. "Quarterly Progress Report No.9," Olin Corporation (October 10, 1989).
14. "Quarterly Progress Report No. 10," Olin Corporation (January 10, 1990).
15. "Quarterly Progress Report No. II," Olin Corporation (April 10, 1990).
16. "Quarterly Progress Report No. 12," Olin Corporation (July 10, 1990).
17. "Quarterly Progress Report No. 13," Olin Corpo~tion (October 10, 1990).
18. "Quarterly Progress Report No. 14," Olin Corporation (January 10, 1991).
Comments
L.
19. Comments Dated March 31, 1986 from John W. Gallagher, EPA Region I on
the draft work plans for the site closure and groundwater study.
20. Comments Dated July 8, 1987 from John W. Gallagher, EP A Region Ion the
July 3, 1987letter from James C. Brown, Olin Corporation.
21. Comments Dated July 10, 1987 from Felix Harvey, State of Rhode Island
Department of Environmental Management on the June 1987 It Site Qosure -
Exhibits A Through J," Olin Corporation. .
10.0 Enforcement
10.1 Correspondence
1. Letter from John W. Gallagher, EPA Region I to Venill M. Norwood Jr., Olin
Corporation (February 20, 1986). Concerning expediting the implementation of
the Remedial Action Plan for the site.
2. Letter from John W. Gallagher for Richard C. Boynton, EP A Region I to VerriU
M. Norwood Jr., Olin Corporation (June 12, 1987). Concerning designation of
John W. Gallagher, EPA Region I as the On-Scene Coordinator.
3. Letter from James C. Brown for Verrill M. Norwood Jr., Olin Corporation to
" '. John W. Gallagher, EPA Region I and Felix Harvey, State of Rhode Island
'Department of Environmental Management (June 24, 1987). Concerning
designation of James C. Brown, Olin Corporation as the coordinator for
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.
10.8 EPA Consent Decrees
Page 34
1.
Consent Decree, Arlene Violet vs. United States 01 America, Plaintiff, v.
Defendants, Western Sand and Gravel, et al., United States District Court for the
District of Rhode Island Civil Action No. 86-0608-B (March 5, 1986) with
attached:
A Appendix I, Remedial Action PIan, Consent Decree, Arlene Violet v. United
States 01 America, Plaintiff, v. Defendants, Western Sand and Gravel, et al.,
United States District Court for the District of Rhode Island Civil Action No.
86-0608-B (March 5, 1986).
B. Appendix n, Guaranty of Performance, Consent Decree, Arlene Violet v.
United States of America, Plainlijf, v. Defendants, Western Sand and
Gravel, et al., United States District Court for the District of Rhode Island
Civil Action No. 86-0608-B (March 5,1986).
C. Appendix m, Escrow Agreement, Consent Decree, Arlene Violet v. United
States 01 America, Plainlijf, v. Defendants, Wqtern Sand and Gravel,
et al., United States District Court for the District of Rhode Island Civil
Action No. 86-0608-B (March 5, 1986).
Judgment, James O'Neil, in his capacity as Attorney General 01 the State 01
Rhotk Island v. Western Sand &: Gravel, Inc., et ai, Civil Action No.
83-0788-B; United States of America v. Western Sand &: Gravel, Inc., et ai,
Civil Action No. 86-0608-B (June 3,1987).
2.
Comments
3.
Comments Dated January 2, 1987 from Ethel M. Halsey, Nasonville Water
District on the Consent Decree fued in the United States District Court for the .
District of Rhode Island.
13.0 Community Relations
13.1 Correspondence
1.
Letter from John W. Gallagher, EPA Region I to Ethel M Halsey, Nasonville
Water District (February 21, 1986). Concerning future public meetings.
Meeting Notes, Meeting for the Western Sand and Gravel Site, EPA Region I,
State of Rhode Island Department of Environmental Management, and the
Nasonville Water District (March 5, 1986).
Letter from John W. Gallagher, EPA Region I to Maria K. Flanagan, Nasonville
Water District, (March 17, 1986). Concerning meeting notes from the
March 5, 1986 meeting.
Letter from lohn W. Gallagher, EPA Region I to Leonard Chen, U.S.
Department of Justice Land and Natural Resources Division (August 11, 1986).
Concerning community relations activities for the site.
Letter from Lynne A Fratus, EP A Region I to Jeff Fontaine, Prudential &
Fontaine (December 4, 1989). Concerning the potential for Lot 51 to be
connected to the site waterline.
Letter from Thomas Bercher, Town of Burrillville to Lynne A. Fratus, EP A
Region I (January 2, 1990). Concerning comments on the proposed waterline
design. ..
Letter from Lynne A. Fratus, EP A Region I to Thomas Bercher, Town of
Bunillville (March 7,1990). Concerning a response to the January 2,1990
letter regarding comments on the proposed waterline design.
2.
3.
4.
s.
6.
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Page~
13.2 Community Relations Plans
1.
"Community Relations Plan - Western Sand & Gravel Supetfund Site,
Buni1lville, Rhode.Island,'.' Alliance Technologies Corporation
(November 1990). .
.. .
13.3...'News ClippingsJPress Releases
News Clippings
-
'-'
.jJ
1.
2.
"BiD Filed to Form New Water District," Woonsocket Call- Woonsocket,
Rhode Island (January 27, 1986). .
''Federal Officials Okay Settlement for Dump's Cleanup," Evening Bulletin -
Providence, Rhode Island (November 15,1986).
''Water District Locks Hams With EP A," Woonsocket Call - Woonsocket, RI
(December S, 1990). .. . .
"The U.s. Environmental Protection Agency Invites Public Comment on the
Proposed Plan for Groundwater Ceanup at the weStern Sand & Gravel
SuperfuDdSite," WoonsocketCall- Woonsocket, RI (February 4,1991).
3.
4.
Press Releases .
S. "Environmental News - Cleauup Plans fa Picil10 and Western Sand & Gravel
Sites Announceci," EPA Region I (October 1,1985).
6. ''Environmental News - The U.S. Environmental Protection Agency (EPA)
announced today that $150,000 has been allocated for the design of a public
water supply for homes near the Western Sand & Gravel Superfund hazardous
. waste site in Bwrillville, Rhode Island," EP A Region I (May 19, 1986).
7. "Environmental News - $S.8 Million Settlement Announced for Western Sand &.
Gravel Cleanup," EPA Region I (November 14, 1986).
8. "Environmental News - Ceanup SettlementFina1ized forWest.em Sand &
Gravel Waste Site," EPA Region I (June 4,1987).
9. "Environmental News - Ceanup Work Begins at the Western Sand & Gravel
Waste Site," EPA Region I (August S, 1987).
10. ''Environmental News," EPA Region I (November 14, 1989). Concerning the
announcement of a November 28, 1989 Public Meeting to discuss construction
of a waterline near the site.
11. "News Release," U.S. Anny Corps of Engineers (March 19, 1990).
Concerning the announcement that construction of an elevated water storage tank
and a pumping station wiD begin in April 1990. .
12. "Environmental News," EPA Region I (April 19, 1990). Concerning the
announcement of the waterline construction schedule.
. 13. "The United.States Environmental Protection Agency Invites Public Comment
on the Proposed Plan for Groundwater Cleanup at the Western Sand & Gravel
Site," EPA Region I (February 4,1991).
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Page 36
13.4 Public Meetings
1., - ''Nasonville Water District," EP A Region I (October 9, 1986). Concerning
project schedule and responsibilities.
...2. Me!Cting Notes, Consent Decree Public Meeting, EP A Region I, State of Rhode
Island Department of Environmental Management, and State of Rhode Island
Office of the Attorney General (December 15, 1986).
3. "Summary of the Public Infonnational Meeting on the Proposed Plan"
(February 11, 1991).
4. Cross-Reference: Transcript of the March 28,1991 Public Hearing on the
Proposed PIan is an attachment to the Responsiveness Summary which is an
attachment to the April 16, 1991 "Record of Decision," EP A Region I [Filed and
cited as entry number 1 in 5.4 Record of Decision (ROD)].
13.5 Fact Sheets
1.
"EPA Announces the Results of Remedial Investigation and Risk Assessment
for Groundwater Contamination," EPA Region I (November 1990).
14.0 Congressional Relations
14.1 Com:spondence
1.
Letter from John R Chaffe, Member of the United States Senate to Julie Belaga,
EP A Region I (December 11, 1990). Concerning the desire that the EP A
consider paving roads near the site as a means of maintaining the remedy.
Letter from Julie Belaga, EP A Region I to John R Chaffe, Member of the
United States Senate (January 4,1991). Concerning EPA's response to the
December 11, 1990 letter.
16.0 Natural Resource Trustee
2.
16.1 COIrespondence
1.
Letter from Gordon E. Beckett, U.S. Department of the Interior Fish and
Wildlife Service to John W. Gallagher, EPA Region I (July 21, 1987) with
attached April 27, 1984 Letter from Bruce Blanchard, U.S. Department of the
Interior Office of the Secretary to Gene Lucero, EP A Headquarters. Concerning
coordination in the development and review of draft documents re.lating to site
activities.
Letter fromL)'nne A. Fratus, EPA Region I to Kenneth Finkelstein, U.S.
Department of Commerce National Oceanic and Atmospheric Administration
(Februaty 27, 1990). Concerning transmittal of the February 1990 "Draft
Groundwater Remedial Investigation Report," Olin Corporation.
Letter from Lynne A. Fratus, EPA Region I to William Patterson, U.S.
Department of the Interior (February 27,1990). Concerning transmittal of the
February 1990 "Draft Groundwater Remedial Investigation Report," Olin
Corporation.
Letter from Lynne A. Fratus, EPA Region I to Kenneth Finkelstein, U.S.
Department of Commerce National Oceanic and Atmospheric Administration
(April 2, 1990). Concerning transmittal of the February 1990 "Draft
Groundwater Remedial Investigation Report - Appendix 0," Olin Corporation.
Letter from Lynne A. Fratus, EPA Region I to William Patterson, U.S.
Department of the Interior (Apri12, 1990). Concerning transmittal of the
February 1990 "Draft Groundwater Remedial Investigation Report -
Appendix 0," Olin Corporation.
2.
3.
4.
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16.1 Correspondence (cont'd.)
6. Letter from Lynne A. Fratus, EP A Region I to Kenneth Finkelstein, U.S.
. - ~t of Commerce National Qcc,nic and Atmospheric Administration
(May 9, 1990). Concerning transmittal of the May 1990 ''Draft Groundwater
Feasibility Study Report - Volume 1," Olin Corporation.
7. Let1er from Lynne A. Fratus, EPA Region I to William patterSon, U.S.
Department of the Interior (May 9, 1990). Concerning transmittal of the May
1990 "Draft Qmandwatcr Feasibility Study Report - Volume 1," Olin
Corporation. .
8. Letter from Lynne A. Fratus, EPA Region I to Kenneth Finkelstein, U.S.
Department of Commerce Nati9D3l Oceanic and Atmospheric Administration
(Febnwy 4, 1991). Coaceming an update of site activities and transmittal of the
addenda to the Remedial Investigation and Feasibility Study Reports.
9. Letter from Lynne A. Fratus, EPA Region I to William PatterSOn, U.S.
Department of the Interior (February 4, 1991). ~ceming an update of site
activities and transmittal of the addenda to the Remedial Investigation and
Feasibility Study Reports.
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./J
Page 3.,
16.4 TJUSUjC Notification Form and Selection Guide
1.
Letter from Pa1Iida L. Meaney for Merrill S. Hohman, EP A Region I to William
Pattmon, U.5.. Department of the Interior (May 20, 1986) with attached Trustee
Notification Form. .
Leu&7 from Patricia L. Meaney for Mcnill S. Hohman, EP A Region I to Sharon
Christophmon, U.S. Department of the Interior (May 20, 1986) with attached
Trustee Notification Form. .
2.
17.0 Site Management Records
17.2 Access Records
1.
Letter from William Walsh-Rogalski, EP A Region I to Michael Mosco,
Hinckley, Allen, Tobin and Silverstein (Attorney for Philip A. Hunt Chemical
Corporation) (November 18,1985) with attached "Declaration of Restrictions
and Protective Covenants Imposed Upon the So-Called Western Sand & Gravel
Hazardous Waste Disposal Site."
Letter from Gregory L. Benik, Hinckley, Allen, Tobin and Silverstein (Attorney
for Philip A. Hunt Chemical Corporation) to Susan B. Squires, State of Rhode
Island Office of the Attorney General (May 21, 1986). Concerning the
tranSmittal of deed restrictions.
2.
The record cited in entry number 3 is an oversized document and may be reviewed, by
appointment only, at EPA Regionl, Boston, Mass~husetts.
3.
Cross Reference: Letter from State of Rhode Island Department of
Environmental Management (July 24, 1989). Concerning transmittal of attaChed
final signed casement drawings [FlIed and cited as entry number 8 in 6.4
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Page 38
17.4 Site PhotographslMaps
The photographs and maps referred to in entry numbers 1 through 5 may be reviewed,
by ll1!pointment only,.at EPA Region 1, Boston, Massachusetts.
1.
2.
Six 5" x 7" Photographs of the site prior to construction of the Cap, Western
Sand and Gravel Site.
Nine 3" x 5" Photographs of Construction of the Cap, Western Sand and Gravel
Site. .
Two 4" x 6" Photographs of Construction of the Cap, Western Sand and Gravel
Site.
One 5" x 7" Photograph of the Completed Cap, Western Sand and Gravel Site.
Letter from Verrill M Norwood Ir., Olin Corporation to Iohn W. Gallagher,
EP A Region I (Ianuary 17, 1986). Concerning two maps of the Topographic
Plan of Land for the Philip A ~unt Chemical Corporation. .
17.7 Reference Documents
3.
4.
5.
1.
Technical Paper: "Field Evaluation of Three Methods of Soil-Gas Measurement
for Delineation of Ground-Water Contamination," Henry B. Kerfoot, Lockheed
Engineering and Management Services Company, Inc. (Ianuary 1988).
Technical Information Packet Regarding Petrex Soil Vapor Surveys, Northeast
Research Institute, Inc.
17.8 State and Local Technical Records
2.
1.
2.
"Table - Groundwater Elevations," (November 13, 1985).
"Table - Groundwater Elevations," (March 14, 1986).
18.0 Initial Remedial Measure (IRM) Records
18.1 Correspondence
Nasonville Water District
1.
Memorandum from Ethel M Halsey, Nasonville Water District to Iohn W.
Gallagher, EPA Region I (February 18, 1987). Concerning water sampling
results.
. Olin'Corpcntion
2. Letter from Verrill M Norwood Ir., Olin Corporation to Iohn W. Gallagher,
EPA Region I (October 15, 1985). Concerning domestic well reports.
3. Letter from Verrill M Norwood Ir., Olin Corporation to Iohn W. Gallagher,
EP A Region I (November 14, 1985). Concerning summary of the
November 7, 1985 meeting.
4. Letter from Iohn W. Gallagher, EPA Region I to Verrill M Norwood Ir., Olin
Cmporation (November 22, 1985). Concerning review of the
November 7, 1985 meeting.
5. Letter from Iohn W. Gallagher, EPA Region I to Verrill M Norwood Ir., Olin
Corporation (February 7,1986). Concerning review ofOlin's'proposal to
change the analysis program for the Interim Water Program.
6. Letter from Robert D. McCaleb, Olin Corporation to Iohn W. Gallagher, EPA
Region I (Ianuary 30, 1987). Concerning domestic well water sampling
program.
7. Letter from John W. Gallagher, EP A Region I to Robert D. McCaleb, Olin
Corporation (April 27, 1987). Concerning interim water supply response
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Page 39
18.1 Correspondence (cont'd.)
Olin Corporation (cont'd)
.' -
.'" 8. Letter from Robert D. McCaleb, Olin Corporation to Lynne A. Fratus, EPA
Region I (November 15, 1990). Concerning the Domestic Well Program.
-
Sta!e of Rhode Island Department of Environmental Management
9. Letter from lohn W. Gallagher, EP A Region I to Felix Harvey, State of Rhode
Island Department of Environmental Management (February 11, 1986).
Concerning analysis program for the interim water supply.
10. Letter from Felix Harvey, State of Rhode Island Department of Environmental
Management to lohn W. Gallagher, EPA Region I (August 18, 1986).
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,
~
Section II
-------
.
GUIDANCE DO~UMENTS
EPA guidance docll~ts may be ~viewcd at EPA Region ~JBoston. Massachusetts.
General EpA C.uidanee Dommenbil
"
1. ~heMive Environmental Re~nse. ContpCnsation. and Liabili\y Act of 1980. amended
October 17, 1986.
-
2. ''PCB Spill CeanupPolicy" {40 CfR Part 1(1), Volume52, Number 63, April 2, 1987
3. "Interim Procedures for Estimating Risks Associated with:Exposures to Mixtures of
Chlorinated Dibcnzo - P - Dioxins and Dibenzofurans ~Ds and CDFs)," EPA Region I,
October 1986.
4. Memorandum fromJ. Winston Jbtt&:r to Addtessees.("Begiona1 Administrators, Regions I-X;
Regional Counsel, Regions I-X; Diredor. Waste Managttment Division, Regions I, IV, V,
VII,and VIII; Director, Emergency and"Remedial.Responsc DiVision. Region n; Director,
Hazardous Waste Management Divman, Regi0D5m and VI; DiIectcn-, Toxics and Waste
Management Division. Region IX; Director, Hazardous W.aste Division. Region X;
Environmental Services Division Directars, Region I, VI, 1II1d VII"), July 9,1987 (discussing
interim guidance on compliance widt appIicab1e one1evant and A}I}I!VjRiate requirements).
5. "National Oil and }ln~I'QOUS SubstaDces Pollution Contingency Plan.1I (40 CFR Part 3(0),
November 20, 1985.
6. U.S. Department of Health and Human Services. NationalIiD&titute for Occupational Safety -
and Health. and Occupational Safety and Health Administmticn. Occupational SafetY and
Health Guidance Manual for Hn~mous Waste Site Activffies.rOctober 1985.
7. U.S. EnvironmentaI Protection Agency. .ot'fire of EmerFi~ and Remedial Response.
CommunitY Relations in Su,perfund: A Handbook (Interim Version) (EPAJHW-6. OSWER
Directive 9230.0-3A), June 1988..
8. U.S. Environmental Protection Agency. OfflCC'ofEme!5"I1~ and Remedial Response. A
Compendium of Superfund Field Qperations Methods (EPAl5401P-87/001, OSWER Directive
9355.0-14), December 1987.
9. U.S. Environmental Protection Agency~ Office of Emergency and Remedial Response.
Guidance on Remedial Actions for Contaminated Omtmdwater at Sqperfund Sites (OSWER
Directive 9283.1-2). December 1988.
10. U.S. Environmental Protect;ion A,gency. Offi= of EmeI'FJIC.Y and Remedial Response.
Superfund Federal-T ~~ti RemediatErWect ~~ment ~ (EPAl5401G-871001.
OSWER Directive 9355.1-1), Decembet 19J6.
11. U.S. EnvinJmnentaJ Protection Agencr~ Office of Emergenoy and Remedial Response.
Sqperfund..S.tate-Lead Remedial PrQject Mana~mentHandbook. (EPAl5401G-871OO2),
December 1986-
12. U.S. Environmental Protection Agency. Office of~~....)' 1Uld Remedial Response.
Superfund Public Hea1th Evalua~ (OSWER Dimctive 9285.4-01), October 1986.
, 13. U.S. Environment3I PrOtection Agency. OffICe of Emergenoy and Remedial Response.
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.Page 41
14. U.S. Environmental Protection AgenCy. Offwe of E~ergency and Remedial Response.
Interim Final Guidance on Conductine R~Mial Investieations and FeasIbilitY Studies under
CERCLA (Conwrehensive EnvironmCQtal Re!ipo!,se. Compensation. and LiabilitY Act),
October 1988.
15. U.S. Enyironmen!al Protection Agency. Office of Health and Environmental Assessment
A Con\pendium ofTechnol~es Used in the Treatment ofHSI7~mnus Waste
(EPN625/8-871014), September 1987.
16. U.S. Environmental Protection Agency. Office of Research and Development Hazardous
Waste Engineering Research Laboratory. Technolo~ Briefs: Data Req,uirements for Selectine
Remedial Action TechnolOjy (EPA/600/2-87/001), January 1987.
17. U.S. Environmental Protection Agency. Office of Research and Development Hazardous
Waste Engineering Research Laboratory. Treatment Technolo~ Briefs: Alternatives to
Ha7~mous Waste LandIdls (EPA/600/8-861017), July 1986.
18. U.S. Environmental Protection Agency. Office of Research and Development Hazardous
Waste Engineering Research Laboratory. Handbook: Remedial Action at Waste Di!iposal Sites
lReviseQ) (EP A/625/6-85/006), October 1985.
19. U.S. Environmental Protection Agency. Office of Solid Waste and Emergency Response.
Data QualitY O~ectives for Remedial R~se Activities: Develqpment Process
(EP A/540/G-87/003), March 1987.
20. U.S. Environmental Protection Agency. Office of Solid Waste and Emergency Response.
Interim Guidance on Superfund Selection of Remedy (OSWER Directive 9355.0-19),
December 24, 1986.
21. U.S. Environmental Protection Agency. Office of Solid Waste and Emergency Response.
Additional Interim Guidance for Fiscal Year 1987 Record of Decisions. July 24, 1987.
22. U.S. Environmental Protection Agency. Office of Solid Waste and Emergency Response.
Draft Guidance on CERCLA Compliance with Other Laws Manual (OSWER Directive
9234.1-01), August 8, 1988.
23. U.S. Environmental Protection Agency. Office of Solid Waste and Emergency Response.
Alternate Concentration Limits Guidance (OSWER Directive 9481.00-6C,
EPA/530-SW-87-o17), July 1987.. .
24. U.S. Environmental Protection Agency. Office of Solid Waste and Emergency Response and
Office of Emergency and Remedial Response. Mobile Treatment Technolo~es for Superfund
Wastes (EP A 54012-861003 (t), September 1986.
25. U.S. Environmental Protection Agency. Region I Risk Assessment Work Group. .
Supplemental Risk Assessment Guidance for the Superfund PrQp-am (BPA 900115-89-0(1),
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