SEVENTH FIVE-YEAR REVIEW REPORT FOR
WESTERN SAND & GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
£
<
3D
O
\
S2.
ro
z
RRO^^°
o
Prepared by
U.S. Environmental Protection Agency
Region 1
Boston, Massachusetts
Olson, Bryan
Digitally signed by Olson,
Bryan
Date: 2023.09.21 18:28:40
-04'OO1
Bryan Olson, Director Date
Superfund and Emergency Management Division
-------
Table of Contents
LIST OF ABBREVIATIONS & ACRONYMS 2
I. INTRODUCTION 3
FIVE-YEAR REVIEW SUMMARY FORM 5
II. RESPONSE ACTION SUMMARY 5
Basis for Taking Action 5
Response Actions 6
Status of Implementation 10
Systems Operations/Operation & Maintenance 10
IC Summary Table 1 1
III. PROGRESS SINCE THE LAST REVIEW 13
IV. FIVE-YEAR REVIEW PROCESS 15
Community Notification, Involvement & Site Interviews 15
Data Review 17
Site Inspection 21
V. TECHNICAL ASSESSMENT 22
QUESTION A: Is the remedy functioning as intended by the decision documents9 23
QUESTION B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action
objectives (RAOs) used at the time of the remedy selection still valid9 24
Question B Summary 24
Changes in Standards and TBCs 24
Changes in Toxicity and Other Contaminant Characteristics 27
2022 CVS-1,2-Dichloroethylene non-cancer toxicity value 27
2022 PFB A non-cancer toxicity value 27
2021 PFBS non-cancer toxicity value 28
2020 Trans-1,2-dichloroethylene non-cancer toxicity value 28
Changes in Risk Assessment Methods 29
Changes in Exposure Pathways 29
Expected Progress Towards Meeting RAOs 3 1
QUESTION C: Has any other information come to light that could call into 3 1
question the protectiveness of the remedy9 31
VI. ISSUES/RECOMMENDATIONS 32
OTHER FINDINGS 32
VII. PROTECTIVENESS STATEMENT 32
VIII. NEXT REVIEW 34
APPENDIX 35
1
-------
LIST OF ABBREVIATIONS & ACRONYMS
ARAR
Applicable or Relevant and Appropriate Requirement
CERCLA
Comprehensive Environmental Response, Compensation, and Liability Act
CFR
Code of Federal Regulations
CIC
Community Involvement Coordinator
COC
Contaminants of Concern
EPA
United States Environmental Protection Agency
FYR
Five-Year Review
ICs
Institutional Controls
ICL
Interim Cleanup Level
IRM
Initial Remedial Measure
LNAPL
Light Non-Aqueous Phase Liquid
MCL
Maximum Contaminant Limit
MNA
Monitored Natural Attenuation
NCP
National Oil and Hazardous Substances Pollution Contingency Plan
NPL
National Priorities List
O&M
Operation and Maintenance
OU
Operable Unit
PCB
Polychlorinated Biphenyl
PFAS
Perfluoroalkyl and Polyfluoroalkyl Substances
PFBA
Perfluorobutanoic Acid
PFBS
Pert!uorobutanesulfoni c Acid
PFHpA
Pert!uoroheptanoic Acid
PFHxA
Pert!uorohexanoic Acid
PFHxS
Perfluorohexane Sulfonate
PFNA
Pert]uorononanoic Acid
PFOA
Perfluorooctanoic Acid
PFOS
Perfluorooctane Sulfonate
PFPeA
Pert!uoropentanoic Acid
PRP
Potentially Responsible Party
PPb
Parts per Billion
PPm
Parts per Million
ppt
Parts per Trillion
RAO
Remedial Action Objectives
RCRA
Resource Conservation and Recovery Act
RIDEM
Rhode Island Department of Environmental Management
RfC
Reference Concentration
RfD
Reference Dose
RIPDES
Rhode Island Pollution Discharge Elimination System
ROD
Record of Decision
RPM
Remedial Project Manager
TBC
To be considered
TCA
1,1,1 -Trichloroethane
TCE
Trichloroethene
UU/UE
Unlimited Use and Unrestricted Exposure
2
-------
I. INTRODUCTION
The purpose of a Five-Year Review (FYR) is to evaluate the implementation and performance of a
remedy to determine if the remedy is and will continue to be protective of human health and the
environment. The methods, findings, and conclusions of reviews are documented in Five-year review
reports such as this one. In addition, FYR reports identify issues found during the review, if any, and
document recommendations to address them.
The U.S. Environmental Protection Agency (EPA) is preparing this Five-year review pursuant to the
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Section 121,
consistent with the National Oil and Hazardous Substances Pollution Contingency Plan (NCP) (40 CFR
Section 300.430(f)(4)(ii)) and considering EPA policy.
This is the seventh FYR for the Western Sand & Gravel Superfund Site. The triggering action for this
statutory review is the signature date of the previous FYR. The FYR has been prepared as hazardous
substances, pollutants, or contaminants remain at the site above levels that allow for unlimited use and
unrestricted exposure (UU/UE).
The Site consists of three Operable Units (OUs) which are all addressed in this FYR. OlJ-1 provides a
permanent supply of safe drinking water to area residents. OlJ-11 addressed bulk waste and contaminated
soils through consolidation and construction of an impermeable cap. OlJ-111 addresses the groundwater
remedy via monitored natural attenuation (MNA). The Western Sand and Gravel Superfund Site Five-
Year Review was led by Joe Cunningham, the EPA Remedial Project Manager (RPM). Participants
included Paul Kulpa, Rhode Island Department of Environmental Management (R1 DEM) Project
Manager, and the following staff at U.S. EPA Region 1: Ashlin Brooks, Community Involvement
Coordinator; Courtney Carroll, Human Health Risk Assessor; Valeria Paz, Ecological Risk Assessor;
and Michelle Lauterback, Site Attorney.
The potentially responsible party, 01 in Corporation, was notified of the initiation of the Five-year
review. The review began on 1 1/14/2022.
Site Background
The 2 5-acre Site consists of two abutting properties located in the Towns of Burrillville, Rhode Island
(Map 149, Lot 015) and North Smithfield, Rhode Island (Map 007, Lot 005) (See Appendix B1 - A and
Bl-B). The Site was the location of a sand and gravel quarry operation from 1953 until 1975. From
1975 to 1979, approximately 12 acres of the site were used for disposal of liquid wastes, including
multiple hazardous chemical and septic waste. During a one-year period from May 1978 to April 1979,
hazardous waste manifests indicated that approximately 470,000 gallons of liquid waste were disposed
at the site. Over time, the wastes penetrated the overburden and contaminated the groundwater. In 1980,
EPA removed approximately 60,000 gallons of liquid wastes from the Site. From 1982 to 1984, the RI
DEM operated a groundwater recirculation system to control the spread of groundwater contamination
and to remove light non-aqueous phase liquids (LNAPL). Records indicate that from 1982-1884
approximately 1,000 gallons of LN APL, some of which contained PCBs, was extracted from the site. In
1983, EPA added the Site to the CERCLA National Priorities List (NPL). EPA has issued three Record
of Decision (ROD) documents for the Site, one for each OU as listed above. The Site is being addressed
and managed via Federal, State and potentially responsible party (PRP) actions. Initial actions included
3
-------
installation of point of entry water filters as an Initial Remedial Measure to provide interim protection
for residents who relied upon contaminated groundwater wells as a potable water source until a
permanent alternate water supply became functional.
Contaminated soils and consolidated materials were placed in specially constructed on-site hazardous
waste landfill consistent with Subtitle C of the Resource Conservation and Recovery Act (RCRA). The
RCRA landfill includes an impermeable cap and security fencing to protect the area. Completion of the
RCRA landfill and implementation of the institutional controls which prohibited the use of groundwater
was complete by March 1989.
In September 1994 the alternative water supply became fully operational and served as a permanent
public water supply for 56 impacted residential homes downgradient of the site. The groundwater
cleanup remedy chosen for the site was natural attenuation to Interim Cleanup Levels (ICLs). Progress is
being tracked through an approved sampling plan with annual monitoring reports issued to stakeholders.
The Site was purchased in 2001 by Supreme Mid-Atlantic which constructed a truck body assembly
plant on the southern extent of the property. During con structi on-rel ated blasting activities, two nearby
residents reported turbidity problems in their wells. Elevated levels of lead, above Maximum
Contaminant Levels (MCLs), were found in one of the residential wells. An investigation was conducted
of alleged disposal pits on a portion of the site close to these residents. The disposal pits were not found,
and the concentration of all contaminants were below MCLs in a subsequent sampling round of the
nearby residents. Therefore, this issue was not thought to be site related. The presence of alleged
disposal pits was again brought to the attention of EPA by a resident in February 2023, however, was
unable to be substantiated based upon information available at the time.
Ownership of the property was transferred in January 2018, and it continues to operate as a truck body
assembly plant on the southern extent of the property. The site is bounded by parcels with institutional
controls preventing groundwater use to the North and West and is bound to the south by Douglas Pike
(Route 7). As depicted in Appendix B1-B, the Site contains a parcel within the Town of North
Smithfield. The parcels under Institutional Controls (ICs) are mature areas and significant future
development is not expected. The quarry to the east of the property, which is not under any institutional
controls, has expanded significantly since the last FYR and has been the subject of many complaints by
abutters and nearby residents. The general layout of the Site, as well as the IC areas, are shown on base
maps in Appendix B. It should be noted that the property identified by the North Smithfield Tax
Assessor as Map 149, Lot 005 which abuts the quarry is part of the Western Sand & Gravel Superfund
Site, and is not, as has been incorrectly stated in the past, an upgradient buffer property.
As a result of recommendations in the 2018 Sixth FYR, monitoring wells at the site were evaluated for
the emerging contaminants 1,4 Dioxane and per- and poly-fluorinated alkyl substances (PFAS)
compounds. 1,4 Dioxane and select PFAS compounds were detected above EPA Regional Screening
Levels (RSLs) in several monitoring wells, suggesting wastes disposed on-site may have contained 1,4
Dioxane and PFAS or pre-cursor chemicals such as fluorotelomers. This finding is consistent with other
liquid waste disposal sites in the region.
4
-------
FIVE-YEAR REVIEW SUMMARY FORM
Site Name:
Western Sand & Gravel
EPA ID:
RID009764929
Region: 1
State: Rl
City/County: Burrillville and North Smithfield;
Providence County
NPL Status: Final
Multiple OlJs?
Yes
Has the site achieved construction completion?
Yes
Lead agency: EPA
Author name: Joe Cunningham, Remedial Project Manager
Author affiliation: U.S. EPA, Region 1 - New England
Review period: 9/26/2018 - 9/26/2023
Date of site inspection: 12/1/2022
Type of review: Statutory
Review number: 7
Triggering action date: 9/26/2011
Due date: 09/26/2023
II. RESPONSE ACTION SUMMARY
Basis for Taking Action
From 1975 to April 1979, a portion of the Site (approximately 12 acres) was used for the disposal of
liquid wastes, including chemicals and septic waste, into unlined lagoons and pits. Over time the wastes
penetrated the soils, overburden, fractured bedrock, and contaminated the groundwater. A fire in March
1977 in one of the chemical pits resulted in local fire officials ordering the Site owner to remove the
chemicals from the pit, and the contents were reportedly buried. Also in 1977, residents began
complaining about odors emanating from the Site. In February 1979, due to concerns regarding local
water supplies, nearby wells were sampled by the Rhode Island Department of Health (R1DOH). In
September 1984, RI DEM completed the first Remedial Investigation/Feasibility Study (RI/FS) for the
Site under a cooperative agreement with EPA.
5
-------
The conclusions of the RI included:
• Organic chemicals had infiltrated through highly permeable soil into groundwater;
• Organic chemicals had migrated off-site and residential wells downgradient from the Site were
contaminated, thus impacting the quality and safety of residential drinking water supplies;
• Contaminated groundwater had discharged into nearby Tarkiln Brook and Slatersville Reservoir;
• Contaminated soil and sludge existed in various locations on the Site; and
• Hazardous air emissions were not detected at the Site.
Findings in the 1984 OU-I ROD and the 1985 OU-II ROD demonstrated that both human and
environmental receptors existed which could potentially be exposed to contaminants occurring at
concentrations in excess of State and Federal standards. The primary exposure to Site contamination was
presumed to be through direct contact and/or ingestion of soils, sludge, and sediments in waste
basins/lagoons; direct contact and/or ingestion of surface water; and ingestion of contaminated
groundwater. The subsequent 1991 ROD for OlJ-111 identifies Site Contaminants of Concern (COCs),
including, but not limited to the organic chemicals Benzene, chlorobenzene, toluene, xylenes, 1,1,1-
trichloroethane, trichloroethene, tetrachloroethene, 1,2- dichloroethane, 1,1-dichloroethane, and vinyl
chloride. Inorganics chemicals include arsenic, chromium, and lead. For a complete list of all COCs
listed in the ROD for OlJ-111, see Appendix H. For a summary table of COCs that have yet to meet
cleanup goals and their respective Groundwater Interim Cleanup Levels, please see Table 1.
It should be noted that the presence of 1,4-Dioxane and PFAS compounds at concentrations higher than
the EP A RSL and the State of Rhode Island interim water quality standards were detected in several on-
site wells during sampling events conducted in 2018, 2019, 2020 and 2021. Neither 1,4-Dioxane nor any
PFAS compounds have been added as a COC for this site. Therefore, these compounds are not reflected
in the remedial action objectives or interim cleanup levels at this time.
Response Actions
The initial response actions included the following:
• 1979: RI DEM issued a Cease-and-Desist Order for violations of water and air regulations at the
Site;
• 1980: Approximately 60,000 gallons of VOC-contaminated liquids were pumped and removed
from lagoons by EPA. This action was taken under the authority of Section 3 1 1 of the Clean
Water Act, prior to passage of CERCLA;
• 1981: The Site was proposed for listing on the NPL in October 1981;
• 1982: RI DEM, as the lead agency at the time, began a groundwater recirculation system to limit
the spread of groundwater contamination and reduce the size of the contaminant plume;
• RI DEM and EPA conducted Rl/FS studies at the Site from 1982 to 1985 for OUs I and II; and
• The site was formally listed on the NPL in September 1983.
Remedial Actions have been performed on each of three OUs as detailed below.
Operable Unit I Remedy Selection/Implementation
The 1984 ROD for OIJ-I contained the following remedial objectives:
• Provide residents in the affected area with a permanent supply of safe drinking water;
• Abate local sources of contamination at the Site; and
• Minimize future public health risks by restricting site access.
6
-------
The ROD specified the following actions to achieve these objectives:
• The installation of point of entry water filters as an Initial Remedial Measure to provide protection
for homes where contaminants were identified in wells used as a potable water source until the
permanent water supply became functional; and
• The installation of a permanent alternate water supply to service approximately 56 parcels of land.
Beginning in August 1984, 01in Hunt Specialty Products, Inc. (Olin), a PRP at the Site, installed water
filters in private homes with contaminated wells and in homes that might become contaminated. EPA
began construction of the permanent water supply system in April 1990 which became operational in
September 1994. The water supply system ownership was transferred to the State of Rhode Island on
September 16, 1992, and subsequently transferred to a privately owned water utility, the Nasonville
Water District. R1DOH is responsible for ensuring that the water supply is being operated and
maintained properly and remains protective of human health.
Operable Unit II Remedy Selection/Implementation
The 1985 ROD contained the following additional remedial objectives:
• Contain or remove sources of contamination at the Site to minimize the continued release of
contaminants to the groundwater and potential public exposure and associated health impacts; and
• Mitigate the environmental impact of contaminated groundwater.
The ROD specified the following actions to achieve these objectives:
• Consolidation of contaminated materials and disposal at an on-site RCRA landfill;
• Grading of contaminated soil to the cap area;
• Installation of an impermeable cap consistent with RCRA provisions;
• Removal and disposal of the groundwater recirculation system;
• Final Site grading with loam and the seeding of the cap and surrounding surface; and
• Securing the Site with a fence and posting of the Site.
The ROD also required the following operation and maintenance activities:
• The inspection and maintenance of the cap, fence, and postings consistent with RCRA provisions.
• Continue groundwater monitoring consistent with RCRA post-closure provisions.
Construction activities for OlJ-11 were complete by March 1989. All contaminated soils were excavated
and consolidated under approximately 2-acres of a RCRA Subtitle C impermeable cap. The entire Site
was graded and the cap plus its surrounding areas were fenced and posted with warning signs. The
fenced area comprises approximately six acres of the 2 5-a ere Site. Post-closure monitoring and
inspections of this fenced area are ongoing by PRPs.
Operable Unit III Remedy Selection/Implementation
The 1991 ROD contained the following remedial objectives:
• Restore contaminated groundwater in the overburden aquifer from the boundary of the existing
cap to the outer boundary of the contaminated plume to State and Federal ARARs, including
drinking water standards, and to a level that is protective of human health and the environment as
soon as practical;
7
-------
• Restore contaminated groundwater in the bedrock system to state and federal ARARs including
drinking water standards, and to a level that is protective of human health and the environment as
soon as practical unless EPA determines, based on additional information, that contamination in
the bedrock does not exceed minimum protective levels.
The ROD specified the following to achieve these objectives:
• Use of natural attenuation as the primary remedial method for contaminated groundwater.
However, due to concerns expressed by R1 DEM, a contingency was added which required
routine re-evaluation of the observed degradation rate of the COCs, and in the event re-evaluation
of models and/or statistical analysis demonstrated that groundwater would not be restored to
interim cleanup levels within 24 to 28 years from the date of the OU-III ROD, an active remedial
method was required. As the OU-III ROD went into effect on 04/16/1991, the groundwater was
expected to be restored to interim cleanup levels between 04/16/2015 and 4/16/2019 (N.B., This
was later amended by a December 11, 2012 letter issued by EPA which changed statistical
methods and extended the cleanup time to 33.2 years).
• Utilization of ICs to reduce the risk to public health from consumption of groundwater.
• Implementation of a Site monitoring program to include long term monitoring of the
groundwater.
Four indicator compounds ICLs were established, as shown in Table 1. For the complete list of COCs,
see Appendix H.
Indicator Compound
Interim Cleanup Level (ICL)
Benzene
5 |.ig/L
Tetrachloroethene (PCE)
5 |ig/L
Trichloroethene (TCE)
5 |.ig/L
Vinyl Chloride (VC)
2 |ig/L
Table 1: ICLs for four indicator compounds used to determine if natural attenuation was occurring.
Performance requirements for periodic evaluations of the natural attenuation remedy were initially
identified in the 1993 Site Monitoring Plan. Submittal of the first evaluation was completed in
accordance with the Site Monitoring Plan and the CD Statement of Work and was presented in
Appendix E to the 1994 Data Report, dated February 1995. The evaluation showed that the statistical
test passed for the indicator compounds tetrachloroethene, trichloroethene, and vinyl chloride only when
outliers were excluded. The report made recommendations regarding treatment of outliers for the
indicator compound benzene and a further recommendation of the benzene theoretical curve based on
the additional information derived from a review of the groundwater modeling assumptions and
modeling parameters reported in the literature.
Following submission of the 1994 Data Report, three consecutive quarters of groundwater monitoring
showed benzene maximum concentrations to be at, or below, the theoretical curve. However, for the
period December 1995 through December 1996, three of the five quarters showed benzene maximum
concentrations to be above the theoretical curve. As a result, and consistent with the CD Statement of
Work, another periodic evaluation was completed and submitted to EPA in April 1997. That evaluation
suggested a change to the Wilcoxon statistical test to better represent outliers and variable environmental
data.
8
-------
The 1997 proposal for modification of the statistical test received EPA concurrence during the
development of the second FYR in 1998. With this modification to the statistical analysis, active
remediation would be implemented only if both of the following conditions are met for any of the four
indicator compounds:
• In applying the Wilcoxon Signed Rank Test, the null hypothesis is rejected in favor of the alternative
hypothesis that attenuation is occurring at a rate slower than predicted by the theoretical curve; and
• Least squares regression fails to identify a statistically significant negative slope at the 95 percent
confidence level.
Due to growing concerns that the statistical methods and assumptions being used were not appropriate
for site conditions, EPA sent a letter to the project team on December 1 1, 2012, requesting the
assumptions and methods be reevaluated. As a result, on February 22, 2013, EPA issued a letter which
required the following modifications:
• The Wilcoxon Rank Sum Test and the Mann-Kendall Trend Test are now applied with the
stipulation that both tests must fail in order for active remediation to be considered. The Wilcoxon
Rank Sum Test determines whether the actual measured concentrations are statistically different
than those predicted by the theoretical equations. The Mann-Kendall Trend Test determines
whether there is a statistically significant increasing or decreasing trend of maximum detections
concentrations for each indicator compound through time.
• The theoretical equations for the estimated decline in concentrations of indicator compounds were
revised and are used as a basis of comparison in the application of the Wilcoxon Rank Sum Test
• Apparent outliers are to be determined via an alternative linear regression approach that offers a
statistical and reasonable approach to revealing a probable outlier value. This approach is used to
evaluate potential outlier values in the data sets and to conduct the required trend tests with regard
to the outlier values.
The 2013 modification to the statistical approach included updated theoretical degradation rates and it
was concluded that the projected time for achieving natural attenuation of all four indicator compounds
needed to be extended approximately five more years (33.2 years vs 28 years indicated in the 1991
ROD). This would extend the date groundwater is projected to be complaint with the ICLs using natural
attenuation to June 2024.
EPA also requested in the December 2012 letter that additional lines of evidence that natural attenuation
is occurring at the Site be provided. In response, tables were provided in annual reports (beginning with
the 2012 data report) that demonstrate the progress of the natural attenuation remedy. While not
statistical in nature, these tables summarized the means and number of sampling events in which the
reported maximum concentrations of the indicator compounds meet their respective MCLs for
successive five-year periods. These tables also track the number of wells monitored in which the
indicator compounds Benzene, PCE, TCE, and VC are detected and the number of times the reported
results were greater than the respective MCL for each year. Examples of these tables can be found in
Appendix E.
Indicator compound benzene met the ICL sitewide by 2018, and since then only two monitoring wells
remain which exceed indicator compounds ICLs (Monitoring wells C4-S and I1-3S). These monitoring
wells continue to be monitored semi-annually, while routine sampling on the remaining wells has
ceased, with the exception of recent 1,4-Dioxane and PF AS sampling events. For a complete list of all
COCs listed in the ROD for OlJ-111, and their respective Groundwater Interim Cleanup Levels, please
see Appendix H.
9
-------
Status of Implementation
Operable Unit I
The water supply system (implemented in accordance with the OU-I ROD) was completed in September
1994 and is currently operated and maintained by a privately-owned water utility (Nasonville Water
District). The water district currently provides water to 53 residences. RIDOH is responsible for
ensuring that the water supply system is being operated and remains protective of human health. A
review of Consumer Confidence Reports issued by the Nasonville Water District for the calendar years
2019, 2020, and 2021 showed no permit exceedances or substantial deviations, other than failure to issue
reports in a timely manner. The source wells for the Nasonville Water District (Well Field "A" and Well
Field "B") were tested for PFAS in 2018 and had no detections above the reporting level.
Operable Unit 11
Construction activities, including an approximately 2-aere RCRA Subtitle C impermeable cap and
installation of fencing and signage to prevent access, were complete by March 1989. The PRPs have
continued to conduct annual inspections and general maintenance of the grounds and cap, including
inspections of fencing and signage. EPA is not aware of any significant disruptions or failures of the
remedy.
Operable Unit III
A long-term Site monitoring plan, which includes long-term monitoring of groundwater, was developed
in response to the OIJ-III ROD. The natural attenuation remedy continues to be evaluated via statistical
analysis of four indicator compounds (Table 1). Detailed analyses and conclusions are presented in the
annual Data Reports for the Site. ICs were implemented to reduce the potential risk to public health from
consumption of groundwater via prohibition on installation wells on select parcels. In addition to the
ICs, EPA instituted a 300-foot buffer zone in the ROD which prohibits installation of a residential well
for unrestricted use. More detailed information on Site ICs are included in Table 2 on the following
page.
Systems Operations/Operation & Maintenance
The Site RCRA Subtitle C Cap and surrounding area of approximately 6 acres within the fenced area is
mowed semi-annually during the growing season. Grounds maintenance around the monitoring wells
adjacent to the fenced area is also conducted during those times. The access roads alongside the capped
area and to wells downgradient were cleared as necessary as were the fences around the capped area.
During this five-year period minor soil additions were made to settling areas near/within swales and the
southeastern side of the fenced area in 2019 and 2021 with soil stockpiled on-site that met RI DEM
Residential Soil Criteria; the areas were seeded thereafter.
10
-------
IC Summary Table
Tabic 2: Summary of Planned and/or implemented ICs
Media, engineered
controls, and areas that do
not support IJU/UE based
on eurrent conditions
ICs
Needed
ICs Called
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
Site Property and
Groundwater under Site
Yes
Yes
Site Property,
which
includes
parcels 43/50
(now 149/15)
in
Burrillville.
and 7/5 in
North
Smithfield
Prevents any use of
remedial action area
(fenced area) that
could disturb the
integrity of the cap
and surrounding
fenced area.
Prevents use of
groundwater under
site
Declaration of
Restrictions and
Protective
Covenants
Imposed upon are
known as
Western Sand &
Gravel
Hazardous
Disposal Site.
April 23. 1986
Groundwater Use,
Installation of Wells
Yes
Yes
Original
Parcel
43/42B (now
132/006)
Prevents any use of
groundwater or
installation of wells
Declaration of
Groundwater Use
Restrictions and
Protective
Covenants
March 27, 1991
Groundwater Use,
Installation of Wells. Site
Property
Yes
Yes
Site Property
which
includes
Parcels 43/50
(now 149/15)
in
Burrillville.
and 7/5 in
North
Smithfield
Prevents use of
groundwater,
installation of
groundw ater wells,
excavation or
installation of
structures below
groundwater level
that could expose
groundw ater or alter
groundw ater flow in
entire site
Declaration of
groundwater use
restrictions and
protective
covenants
August 23. 1991
Groundwater Use,
Installation of Wells. Site
Property
Yes
Yes
Original
Parcels
43/76, 43/48
in Burrillville
and 7/3 in
North
Smithfield.
Burrillville
parcels are
now 149/014
and 132/007
respectivelv.
Prevents use of
groundwater,
installation of
groundw ater wells,
excavation, or
installation of
structures below
groundwater level
that could expose
groundwater or alter
groundwater flow in
entire Site.
Institutional
Control
Agreement
Western Sand &
Gravel Superfund
Site. Burrillville
and North
Smithfield Rhode
Island,
September 3,
1991.
1 1
-------
Groundwater Use,
Installation of Wells. Site
Property
Yes
Yes
Site Property
which
includes
Parcels 43/50
(now 149/15)
in Burrillville
and 7/5 in
North
Smithfield
Prevents use of
groundwater,
installation of
groundw ater wells,
excavation, or
installation of
structures below
groundwater level
that could expose
groundwater or. alter
groundw ater flow in
entire site
Confirmatory
Declaration of
Groundwater Use
Restrictions and
Protective
Covenants. June
5,1996
Groundwater Use,
Installation of Wells. Site
Property
Yes
Yes
Site Property
which
includes
Parcels 43/50
(now 149/15)
in Burrillville
and 7/5 in
North
Smithfield
Reiterates
Institutional
Controls on property
from previous
documents
Warranty Deed.
Book 771. page
273-277,January
16. 2018
12
-------
III. PROGRESS SINCE THE LAST REVIEW
This section includes the protectiveness determinations and statements from the last Five-year review as
well as the recommendations from the last Five-year review and the status of those recommendations.
Table 3: Protectiveness Determinations/Statements from the 2018 FYR
OH#
Protectiveness
Determination
Protectiveness Statement
1
Protective
OU-I involved the construction of a water supply system
to provide residents in the affected area with a
permanent supply of safe drinking water. The water
supply system has been in operation since September
1994. The remedy at OU-I is protective of human health
and the environment
II
Protective
OU-I 1 involved the consolidation of contaminated soils
to the cap area and construction of an impermeable
barrier over the consolidated contaminated soils. The
OU-I 1 remedy continues to minimize the continued
release of contaminants to the groundw ater and prevents
public exposure to the contaminated soils. The remedy at
OU-I 1 is protective of human health and the
environment.
III
Short-term Protective
The remedy of OU-III currently protects human health
and the environment through implementation of various
response actions, the placement of Institutional Controls
and water line, long-term Monitored Natural Attenuation
with statistical analysis, and the physical control of Site
access in the short term. How ever, in order for the
remedy to be protective in the long-term, the cleanup
levels in the 1991 ROD. or alternative clean-up levels
that are demonstrated to be equally protective, have to be
met to ensure protectiveness.
Sitewide
Short-term Protective
The 2018 FYR concluded that overall, the remedy at the
Site currently protects human health and the
environment through implementation of various
response actions, the placement of Institutional Controls
and water line, long-term Monitored Natural Attenuation
with statistical analysis, and the physical control of Site
access in the short term. How ever, in order for the
remedy to be protective in the long-term, the cleanup
levels in the 1991 ROD. or alternative cleanup levels
that are demonstrated to be equally protective, have to be
met to ensure protectiveness.
13
-------
Table 4: Status of Recommendations from the 2018 FYR
OU#
Issue
Recommendations
Current
Status
Current Implementation Status
Description
Completion
Date (if
applicable)
III
Presence of
Emerging
Contaminant at
Site (PFAS)
Assess extent of
PFAS in
overburden and
bedrock
groundwater at site
Ongoing
See Below
III
Presence of
emerging
contaminant at
site (1,4 Dioxane)
Assess presence of
1,4-dioxane in site
bedrock
groundwater
Completed
See Below
11/2/2021
III
Presence of
emerging
contaminant at
site
Continue to sample
monitoring wells
for a period of time
to evaluate the
attenuation
dynamics of 1,4-
dioxane within the
Site Groundwater
Plume
Ongoing
See Below
Note: There were no recommendations for OU #1 and 2 in the 2018 FYR
Recommendation #1: Assess extent of PFAS constituents in overburden and bedrock groundwater
Samples from 18 on-site wells (2 bedrock, 16 overburden) were collected and analyzed for the presence
of PFAS compounds in 2018 and 2019. PFAS compounds were present above the detection limit in 16
of the 18 monitoring wells, however few exceeded the State standard at the time of collection (70 ppt).
However, multiple wells exceed the 2022 updated EPA RSL for PFOA and PFOS, as well as the
proposed total PFAS standard for the State of Rhode Island which is expected to become law in late
2023. The highest concentrations of PFAS compounds were found in overburden monitoring wells C4-S
and C6-S with peak concentrations of PFOA 680 and 55 ng/L, respectively, with other PFAS
compounds in lower concentrations, including in bedrock wells. The data suggests that PFAS
compounds are present above the RSL in both the overburden and bedrock.
Recommendation #2: Presence of 1.4 Dioxane in Bedrock Groundwater
Sampling and analysis of 1,4 Dioxane in select wells began in 2014, and Recommendation #2 resulted in
the addition of two bedrock monitoring wells, I-2B and I-6B. Samples from the bedrock wells were
collected and analyzed for the presence of 1,4-Dioxane annually between April 2018 and October 2021.
Concentrations of 1,4-Dioxane in the wells ranged from 3.9 to 82 |ig/L, significantly higher than
observed in the overburden wells, and above the RSL of 0.46 |ig/L, and conclusively demonstrated that
1,4 Dioxane was present at the site. Recommendation #2 was completed on November 2, 2021.
Recommendation #3: 1.4 Dioxane attenuation Trends
Recommendation #3 aimed to examine the attenuation dynamics of 1,4 Dioxane over time. However,
sample events were inconsistent, with several wells containing concentrations above the RSL which
were not sampled until the bi-annually sampling events in 2019 and 2020, and not consistently sampled
thereafter. Nine monitoring wells were sampled once and had a concentration of 1,4 Dioxane less than
14
-------
the detection limit (0.020 |ig/L). Further discussion of trends can be found in Section IV, Data Review,
Emerging Contaminants of Concern.
IV. FIVE-YEAR REVIEW PROCESS
Community Notification. Involvement & Site Interviews
Per EPA Region 1 policy, a public notice was made available in a region-wide press release announcing
all upcoming Five-year reviews in New England (See Appendix I). This public notice was sent to all
media in Region 1 where there are Superfund sites with 2023 FYR and the notice was also published on
the EPA New England web page https://www.epa.gov/newsreleases/epa-review-cleanups-four-rhode-
island-superfund-sites-vear on January 18, 2023. This press release invited the public and local officials
to submit any comments to EPA and provided web links to detailed site information on site status and
past assessment and cleanup activity.
During the FYR process, interviews were conducted to document any perceived problems or successes
with the remedy that has been implemented to date. As is typical of every FYR, the project team aimed
to interview the PRP group. Town officials, a representative from the State Environmental Agency, and
select individuals who live in the vicinity of the site. EPA's Community Involvement Coordinator
(CIC) reached out to multiple residents who live in the vicinity of the Site and was also directly
contacted by other residents who wished to participate in the review process. Due to on-going fugitive
dust complaints from residents to State and Federal agencies originating from a parcel adjacent to the
Site containing an operational quarry (North Smithfield Tax Map 7, Lot 38, a/k/a Material Sand & Stone
Corp), EPA conducted more in-depth resident interviews to fully capture the thoughts of the community.
As a result, a total of four residents were interviewed for this FYR. One resident corresponded with EPA
multiple times and provided additional information and context to the concerns of the community. The
results of these interviews are summarized below.
A R1 DEM representative stated that the Site is beneficially being reused for economic development.
They stated that the Site cap is maintained, and all previous cap issues have been addressed. They
believe current performance of the remedy will need to be reevaluated to determine whether emerging
contaminates, such as PFAS, need to be addressed. In addition, institutional controls must be
periodically re-evaluated to ascertain if they are still appropriate. Ongoing inspections, meetings, and
communications with the EPA and PRP representatives have been conducted to ensure that the
aforementioned potential issues are being investigated.
The PRP group's environmental manager noted that the remedy outlined in the three RODs for this Site
continue to effectively protect human health and the environment. All activities prescribed in the first
two RODs have been achieved. The objectives specified in the third ROD have been addressed as ICs
which are currently in place. In addition, natural attenuation has been monitored and proven effective at
significantly reducing concentrations of contaminants of concern. ICs maintained for the Site property
and portions of four surrounding parcels prohibit some residential uses such as installation of
groundwater wells; these restrictions are outlined in documents properly recorded in the Towns of
Burrillville and North Smithfield. The PRP group noted they have also received inquiries from residents
regarding fugitive dust generated at the adjacent quarry east of the Site. Apparently, the residents
mistakenly believed the PRP group was the owner of the active quarry abutting the Site. The PRP group
passed along the residential inquiries to RI DEM.
15
-------
The current property owners believe the Site has not had any effect on the surrounding community. The
owners have, however, also observed fugitive dust issues at the adjacent quarry and independently
reported these concerns to RI DEM. The owners stated that they were told by RI DEM dust mitigation
"wasn't an issue at the gravel site".
The Town Manager of Burrillville is aware of the Site and its status. However, the office has not
recently received information regarding the Site's activities and remedial progress. This is likely due to
the current status of the Site - post remediation and monitoring. The Town Manager notes that deed
restrictions might be in place on surrounding properties. The of Town of Burrillville had no further
comments, suggestions, or recommendations regarding the project.
Despite multiple attempts to contact the Town of North Smithfield, no response to EPA's inquiries were
returned.
Community members and abutting homeowners provided multiple comments. All community members
expressed concerns about fugitive dust from quarry operations at the adjacent property, despite being
told this was a separate property and not part of the Site. However, several individuals expressed
concern over not only the toxicity and carcinogenic properties of the dust due to the inherent nature of
material being handled (quartz and silica), but also dust from material potentially co-contaminated from
historic dumping related to the Site. It should be noted that many of the comments received appear to
confuse the Western Sand & Gravel Superfund Site (Site) with the quarry at the adjacent property.
There is no evidence that the Site is generating any fugitive dust. Instead, the fugitive dust appears to be
solely generated at the adjacent active quarry.
One resident who lives adjacent to the property line between the Site and the active quarry stated that
locations where sand and gravel are currently being processed by the active quarry were historically
used as dump locations. The resident allegedly was told "not to dig" in those locations by the prior
owners of the site. EPA is actively investigating this claim and any potential dumping sites that may not
have been included in the conceptual site model at the time of writing this FYR and investigating the
potential impact of continued quarry operations on the Site remedy.
Some community members noted concerns regarding the cleanup work at the Site. Some stated that the
groundwater well testing performed was "insufficient" and were tested using "inaccurate methods". As a
way of clarification, the analytical well testing methods used at the Site were consistent with best
practices and are appropriate for the contaminants of concern. Other residents said they were not told the
contaminated materials and remedial waste would be taken off-site. It should be noted that no waste was
taken off-site, and all remedial waste was placed in the on-site RCRA Subtitle C compliant hazardous
waste landfill and capped. Finally, several community members stated they would like to receive more
correspondence from EPA regarding ongoing Five-Year Review Efforts and were surprised they weren't
interviewed in previous iterations. Despite explaining that only a small subset of residents are contacted
for participation in the Five-Year review interviews, several wished to be added to the "mailing list" and
expressed a desire to participate in every Five-Year Review moving forward.
In sum, the primary concern in the community is the on-going fugitive dust issue from the adjacent
quarry which is not directly related to the Site. Multiple residents, as well as the owner of the Site, said
they voiced their fugitive dust concerns to RI DEM, but feel their concerns were not adequately
addressed. Several residents stated that they no longer call RI DEM due to ineffective response. The
16
-------
EPA Superfund RPM passed these concerns along to the State coordinator with EPA's Air Resources
program and RI DEM.
The community involvement portion of this Five-Year Review showed that residents are concerned
about air quality and fugitive dust issues from the adjacent quarry. There is, however, confusion in the
community about the relationship between the quarry adjacent and the Site. In addition, many residents
appear to be unclear on the specific remedial actions taken at the Site. To address these concerns, EPA
will develop a fact sheet which reviews the history of the Site, specific remedial actions taken, as well as
distinguish between the Site and parcels adjacent to the Site which may be contributing to concerns
within then community (See "Other Findings").
The results of the review and the completed FYR Report will be made available on EPA's site profile
page at www.epa.gov/superfund/wsg.
Data Review
The site currently contains 19 known viable monitoring wells, 7 historic, closed, or abandoned
monitoring well clusters, and seven piezometers. Of the known monitoring wells, only two, overburden
wells II-3S and C4-S, are still monitored twice annually for contaminants of concern. All monitoring
wells with the exception of 11-3 S and C4-S have met ICLs for contaminants of concern, and approval to
discontinue sampling was given to the remaining wells as the data dictated. 18 wells were sampled for
emerging contaminants 1,4-Dioxane and PFAS compounds during this Five-Year review period.
During the period covered for this FYR, overburden monitoring wells II-3S and C-4S were sampled
biannually and analyzed using EPA Method 8260C. Figure 5 shows data collected during this FYR
period. Tabulated data for detected contaminants of concern from the years 2013-2022 for monitoring
wells I1-3S and C4-S can be found in Table E in the appendix.
Sample Date
II-3S
C-4S
PCE
(fig/L)
TCE
fcg/L}
VC
(re/L>
PCE
(wA)
TCE
(fig/L)
VC
(fig/L)
4/2/2018
0.4
0.1
0.1
1.4
5
BDL
10/17/2018
1.8
BDL
0.08
0.6
1.1
BDL
4/1/2019
0.5
BDL
0.5
0.1
0.2
BDL
10/2/2019
24
BDL
36
42
0.7
BDL
12/12/2019
1.6
BDL
9.3
16
5.2
BDL
9/23/2020
3.1
BDL
37
11
2.7
BDL
4/7/2021
0.37
BDL
0.5
3.3
BDL
BDL
9/29/2021
0.49
BDL
0.5
2.6
BDL
BDL
4/11/2022
0.5
BDL
0.5
0.61
BDL
BDL
10/20/2022
2.4
BDL
23
16
BDL
BDL
Tabic 5: VOC Concentrations in Monitoring Wells II-3S and C-4S
Boldcd values indicate cxcecdance of the ICL; BDL = Below Detection Limit
As shown in Figure 5, all indicator chemicals had at least once exceedance of the ICL during this review
period. PCE exceeded the ICL in 5 of 20 samples, TCE exceeded the ICL in 1 of the 20 samples, while
17
-------
VC exceeded the ICL in 4 of the 20 samples. It should be noted that there were no exceedances of the
TCE ICL in monitoring well 11-3 S, and no exceedances of the VC ICL in monitoring well C-4S. This is
an improvement from the 2018 FYR, where 9 of 20 PCE samples exceeded the ICL, 5 of 20 TCE
samples exceeded the ICL, and 4 of 20 VC samples exceeded the ICL.
Statistical Analysis
A Mann-Kendall test at a level of significance of 0.1 (Confidence Coefficient 0.9) was conducted on
PCE and VC data from the last 40 consecutive sampling events (e.g., 1989 - 2022) and found that both
exhibited statistically significant decreasing trends (Table 6 and Appendix E). TCE was not included as
there was only 1 minor exceedance of the ICL during the period analyzed (5.2 |ig/L in the October 2019
sample event for monitoring well C-4S) and declined to below detection limits in subsequent samples. A
Mann-Kendall test was also conducted on a contaminant and well basis for the data collected during this
FYR period (2018 - 2022) (Table 6 and Appendix E), however was unable to establish a trend at a level
of significance of 0.1. This is most likely due to the relatively low concentration and high variability of
the data and is consistent with intermittent reductive dechlorination at low concentrations.
A one sample Wilcoxon Signed Rank Test with a confidence coefficient of 95% was performed on PCE
and Vinyl Chloride (VC) data from 1989 - 2022 (Appendix E) and found that measured concentrations
were less than the calculated concentrations for the majority of samples, indicating that natural
attenuation is occuring at a rate equal to or higher than predicted. While there are multiple points which
exceed the predicted theoretical concentration, this can be explained by the variable nature of in situ
reductive dechlorination and is not necessarily an indicator of a problem with the remedy.
Analysis
Mann-Kendall Result (95% CI)
PCE Concentration (MW C-4S and 11-3S 1989 - 2022)
Decreasing Trend
VC Concentration (MW C-4S and II-3S) 1989 - 2022)
Decreasing Trend
PCE in MW C-4S (2018 - 2022)
Insufficient Evidence to Identify Trend
PCE in MW 11-3S (2018 - 2022)
Insufficient Evidence to Identify Trend
VC in MW 11-3S (2018 - 2022)
Insufficient Evidence to Identify Trend
Tabic 6: Mann-Kendall Trend Analysis Results
Based on evaluation of criteria presented in the Consent Decree along with the modified and approved
statistical methods, MNA continues to be an effective remedy for the Site. As indicated in the 2021
Annual Data Report, the data suggests that the three remaining indicator compounds for the Site (PCE,
TCE and VC) all show statistically significant downward trends with confidence levels greater than 99
percent, and in the case of TCE in II-3S and VC in C-4S, no contaminant detections. The data show that
natural attenuation has been able to achieve site-wide reductions in the concentrations of the indicator
compounds. Statistical analyses of the indicator compounds, as well as tables and figures documenting
remedy performance, as presented in the 2021 Annual Data Report, are shown in Appendix E.
Emerging Contaminants of Concern
IIMUIIIIIIHIIBBBBBBBIBBIBBfawhBB—BBrtaagaBBBBBBBBBBIBBBBBBBBBBIBBBBBBBBBBBBBBBBBBgWBBBBBBBB—BBBBIIBBBBBBBBBBBBBBIIBBBBBBBBBBBBIBBIBBBBBW
Sampling during this Five-year review period has shown that both the overburden and bedrock
groundwater at this site contains emerging contaminants 1,4 Dioxane and the PFAS compounds
Periluorooctanoic acid (PFOA), Periluorooctane sulfonate (PFOS), Periluorobutane sulfonate (PFBS),
Periluorononanoic acid (PFNA), and Periluorohexane sulfonate (PFHxS).
18
-------
1.4 Dioxane
Sampling and analysis of 1,4 Dioxane in select wells began in 2014 and was expanded by the 2018 FYR
to include the addition of two bedrock monitoring wells, I-2B and I-6B. Samples from the bedrock wells
were collected and analyzed for the presence of 1,4-Dioxane annually between April 2018 and October
2022. Concentrations of 1,4-Dioxane in the bedrock wells ranged from 3.9 to 82 |ig/L, significantly
higher than observed in the overburden wells, and above the RSL of 0.46 |ig/L. Recommendation #3
from the 2018 FYR aimed to examine the attenuation dynamics of 1,4 Dioxane over time.
Nine monitoring wells (C-1D, C-6S, I-2S, 1-3S, I-4D, I-4S, I-6S, I-7D, I1-3S) were sampled once and
had a concentration of 1,4 Dioxane less than the detection limit (0.020 |ig/L). While it is likely that these
wells represent areas that are not contaminated above the RSL, contamination of these wells cannot be
ruled out due to the high data variability observed at other wells and the reliance upon one sample.
The nine remaining wells were sampled multiple times and had concentrations greater than the detection
limit, however, the number of sampling events and concentrations observed were highly variable.
It is important to note that 1,4 Dioxane concentrations appear to be increasing at monitoring well I-6D,
in contrast to decreasing concentrations at 1-3 D and I1-3D. Due to a lack of consistently sampled and
repeatable data, trend analysis could not be performed at this time, however, should be reassessed in the
future as more data becomes available. It should be noted that bedrock wells I-2B and I-6B contained
the highest concentrations observed, and therefore it is reasonable to conclude that majority of
contamination remaining at the Site remains in the fractured bedrock aquifer. As these are the only
bedrock wells included in the sampling event, inclusion of additional bedrock monitoring wells should
be considered to better delineate the 1,4 Dioxane plume in the fractured bedrock.
PFAS
The 2019 - 2021 sampling events demonstrated that multiple PFAS constituents are present at the Site,
primarily located in the immediate vicinity and downgradient of the on-site RCRA Subtitle C landfill.
As shown in Appendix Figures C-9 and C-10, the highest concentrations of total PF AS are in the
vicinity of the former source area and the capped area as would be expected and supports the hypothesis
that the PF AS contamination is the result of dumping related to the site and not likely to be attributed to
off-site sources. Many of the wells in this area exceed both the current Rhode Island standard (70 ppt)
and the EPA RSL in effect at the time of this review (4 and 6 ppt for PFOA and PFOS, respectively),
and in some cases by an order of magnitude. The concentrations attenuate with distance from the source
area, however, multiple downgradient and cross-gradient wells both in the overburden and bedrock
contain concentrations that exceed the EPA RSL, proposed MCL, and proposed RI groundwater
standard. While it is likely the existing groundwater remedy remains protective for PFAS compounds
due to no known exposure pathways on the site (See Question B in Section V), additional data should be
collected to better understand which PFAS compounds are present beyond the six included in the initial
screening, as well an expanded sampling plan which includes off-site or sentinel wells and more
frequent sampling to better understand the distribution and variability of PFAS on the site and potential
off-site pathways. Due to reporting limitations of the method used to screen for PF AS, it is not currently
known what other, if any, PF AS compounds or precursors are present at the site which are being
degraded to regulated PFAS compounds.
19
-------
Groundwater Elevation
Groundwater elevations for all monitoring wells were measured during sampling events and used to
produce piezometric contour maps for the shallow, medium and deep aquifers (see Appendix D). As in
previous reviews, the groundwater contour maps indicate that groundwater flows in a north to north-
west direction and remains consistent with historical observations. There is little deviation between the
shallow, medium, and deep wells, suggesting a relatively homogeneous subsurface conductivity across
the depths evaluated. It should be noted that the groundwater elevations collected in this Five-year
review, and thus the groundwater contours, are limited to wells on the site as has been the case for
multiple FYRs. Historic groundwater monitoring wells exist off-site; however, they have largely been
abandoned.
Regional groundwater flow and COC contaminant pathways have previously been evaluated, however,
changes to land use upgradient of the site, most notably an active quarry to the east of the site which
appears to be infiltrating pumped groundwater on the border of the site raises concerns about potential
impacts to the regional groundwater flow and contaminant pathway models for this site. Groundwater
elevation at on-site wells evaluated during this FYR period remain consistent with historical
observations, however, the infrequent measurement of groundwater elevation on-site (twice annually)
and the erratic and poorly understood groundwater pumping and transport activities upgradient of the
site remain a concern as potential impacts, if any, are unlikely to be captured with the infrequent nature
of current groundwater elevation measurements.
Metals
Due to findings of the 2018 FYR which showed no significant risk due to metals, most notably lead in
the soil, the PRP group was not required to perform metal sampling as part of this 2023 FYR in any
media. As a result, the risk findings are carried over from the 2018 FYR. For additional discussion, see
Question B.
Ecological Risk
The R1 for the Site (dated June 1990) concluded that 1) there were no signs of ecological stress at any
location and 2) concentrations in surface water and sediment represented a negligible potential for
adverse effects to either humans or the environment. In the ROD, EPA stated that "the cancer risks
associated with surface water and 13 sediments from Tarkiln Brook, and the Seep are within
Superfund's Target Risk Range". These findings were re-evaluated in the 2018 FYR, and concurred that
"Overall, the results of the environmental assessment activities conducted at the Site since the issuance
of the ROD in April 1991 do not indicate that there were or had been any significant effects to the
environment or ecological receptors at or in the vicinity of the Western Sand & Gravel Site" (See
Appendix F). Furthermore, "the surface water and sediment assessment activities and the substantial
improvements in groundwater quality at the Site over the past three decades indicate that there are
minimal, if any, impacts to surface water and sediment, and that risks to environmental and human
receptors from potential exposures to surface water and sediment in Tarkiln Brook are de minimis".
There have been no significant changes to cancer slope factors, exposure, or other factors since the 2018
FYR, and therefore the conclusion that there are not any significant effects to the environment or
ecological receptors within the vicinity of the Western Sand & Gravel Site remain valid. However, it
should be noted that these conclusions were based on the COCs contained in the ROD, and do not
include an assessment of emerging compounds 1,4-Dioxane or PF AS constituents which have a low Koc
20
-------
coefficient and thus are more mobile than the COCs evaluated, and it is not unreasonable to hypothesize
that 1,4 Dioxane and PFAS constituents may travel farther than the COC included in the ROD.
Groundwater flows generally north to northeast towards Tarkiln Brook, and groundwater may discharge
to this brook. PFAS has been detected in 11-3, which is the nearest well to Tarkiln Brook. The highest
detection of PFAS is 17.01 ppt in 11-3S, measured in the November 2019 monitoring event. The lowest
available ecological risk screening value for this compound is 2940 ppt (Grippo et al. 2021). Even with
minimal dilution by receiving water in the brook, it is unlikely that surface water concentrations in
Tarkiln Brook would approach a concentration that would be harmful to aquatic life. Sampling of
surface water for PFAS should be considered in the event that future monitoring finds increasing PFAS
concentrations in the upgradient well.
Site Inspection
The inspection of the Site was conducted on 12/1/2022. In attendance were Joe Cunningham, U.S. EPA
RPM; Ashlin Brooks, U.S. EPA Community Involvement Coordinator (CIC); Paul Kulpa, RI DEM
Project Manager; Randy Morris and James Cash well of 01 in Corporation; Jane Parkin Kullmann of
WSP, Environmental consultant for the PRP. The purpose of the visit was to perform a site inspection to
better assess the protectiveness of the remedy and identify areas of concern. The group walked the
interior of the fenced in area which surrounds the WSG cap area first. Soil cover was in good condition
with adequate vegetative coverage for the season. Vegetation along fence line was recently cut and
appears to be well maintained. No visible damage or holes in the fencing. One small depression (< 2 ft
diameter, < 6" deep) in the soil cover approximately 1,000ft from the entrance was observed and
appeared to be due to natural settling of capped materials. 01 in staff indicated this was an infrequent
occurrence, however they maintained a small stockpile of clean soil on-site to fill in depressions as
encountered. No areas of significant concern visible inside of the fenced in area. The group then
inspected all on-site monitoring wells outside the capped area. Wells were in good condition and kept
clear of vegetation to avoid overgrowth. However, two wells, C-6 and C-2, were found to be open, with
both the casing cap and liner seal removed and exposed to the atmosphere. Upon discussion with 01 in
staff present, it appears the caps and seals were removed for sampling by 01 in staff during the summer
sampling event, however, they were inadvertently not replaced. 01 in staff stated they would reiterate the
importance of ensure seals and caps are replaced after sampling.
The group then walked along Tarklin Brook to view the stream gauges. Stream gauges were in good
condition and had recently been replaced with a new design to avoid damage from ice and other debris.
Quarry operations at an adjacent property were clearly visible from the WSG site. US EPA and RI DEM
staff observed a significant amount ot fugitive dust being generated, however, the prevailing wind
appears to carry the dust parallel to the WSG property. Ground level at the quarry appeared to be
significantly lower than at the previous FYR, indicating that a significant amount of material has been
removed from the quarry in the past five years. In addition, four ponds, each approximately 50 x 100
feet are present at the edge of the quarry property. [N.B., In the time since the site inspection was
performed, four additional infiltration basins were constructed along the property boundary, bringing the
total infiltration basins to eight]. Several piles of vegetation debris and rocks were observed on the
hillside between the WSG property and the quarry, indicating that the quarry may be dumping material
in that area. At least one section of the hillside had mild erosion and an absence of leaves, suggesting a
focused discharge may have occurred.
21
-------
Overall, the WSG property appeared to be well maintained, except for failure to replace well caps and
seals on two monitoring wells after sampling. Corrective action was immediately taken by the PRP and
is not considered a significant concern at this time.
V. TECHNICAL ASSESSMENT
This section provides a technical assessment of the remedy implemented at the Site, as outlined in the
Comprehensive Five-Year Review Guidance. The remedy was evaluated based on its function in
accordance with decision documents, its adherence to valid risk data and scenarios, its adherence to
Applicable or Relevant and Appropriate Requirements (ARARs), and any other information that could
have affected the remedy's protectiveness.
22
-------
QUESTION A: Is the remedy functioning as intended by the decision documents?
Operating Unit
Functioning as Intended?
Decision Document
OU-I
Yes
RA Complete Report - September 1994
OIJ-II
Yes
RA Completion - March 1989
OU-I 11
Yes
Construction Complete Report - December 1992
The remedies continue to function as intended by the three Records of Decision for the Site. The water
supply system implemented as OU-I is being operated and maintained by the Nasonville Water District
and continues to provide potable water for area residents. Except for minor violations related to timely
delivery of water quality reports between 2019 - 2022, the water district meets all minimum State and
Federal requirements for a public water supply system and the water provided to residents eliminates the
most significant site contaminant exposure pathway (i .e., ingestion of groundwater from residential
wells) and remains protective.
The landfill cap, installed as part of OIJ-II, is in good condition and is being well maintained by the PRP
group. Minor depressions from settling are promptly filled with soil, and the vegetative cover is
maintained. The landfill cap is secured by a chain link fence that is routinely checked for integrity and
kept clear of brush and fallen trees, and there is no evidence of trespassing. The remedy for OIJ-II is
functioning as designed and remains protective.
The groundwater data collected thus far as part of OU-III indicates that natural attenuation is occuring at
a reasonable and expected rate, and at this time there is no need to consider active remediation. As
required by the ROD and subsequent amendments, statistical analysis was performed using the Mann-
Kendall Trend analysis and Wilcoxon Signed Rank Test and demonstrated that the COC are decreasing
and are consistent with calculated theoretical degradation rates with reasonable confidence. This
provides additional evidence that MNA is resulting in adequate degradation and meets the requirements
of the remedy.
Institutional Controls
Current institutional controls can be viewed in Appendix B3. As shown, institutional controls limiting
access and use of groundwater are present on the Site parcel, as well as four adjoining parcels. The
parcels adjoining the property are wooded lots, except for the truck assembly facility to the south on
Route 7. During the site inspection, there was no evidence of activities prohibited by the institutional
controls on the lots identified in Appendix B3. It should be noted that the adjoining parcel to the east.
North Smithfield Map 7, Lot 5, is only 52 feet at its narrowest point. This means that the parcel which
contains the active quarry (North Smithfield Map 7, Lot 38) is therefore approximately 75 feet from the
boundary of the RCRA Subtitle C cap and upgradient of the site and there are no institutional controls
on this parcel preventing impacts to the downgradient site. As previously mentioned, the parcel at Map
7, Lot 38 contains eight man-made and unlined ponds along the western site boundary which appear to
temporarily store and infiltrate water collected across the quarry, including what appears to be
groundwater from the eastern site of the property, adjacent to the L&RR Superfund site. This is of
concern due to the close proximity of these ponds to the site and the potential to disrupt groundwater
dynamics and surface and/or overland flow discharges. In addition, during the inspection of the
properties with institutional controls, evidence of dumping of vegetative debris and water discharge on
North Smithfield Map 7, Lot 5 was observed, and is presumed to have originated from the parcel at Map
23
-------
7, Lot 38 (i.e., the quarry). RI DEM issued a Rhode Island Discharge Elimination System (RIPDES)
permit to allow infiltration of "stormwater", however is it unclear if impacts to the Site were considered,
or if setback requirements were followed when this permit was issued. Investigations into these
activities are ongoing.
Climate Change
Climate change is not anticipated to significantly impact the effectiveness of the remedies for the Site.
Source water wells for the Nasonville Water District are located on the edge of an area identified by the
State of Rhode Island as a "Effective Flood Zone", and service disruptions are possible from significant
flooding events. However, a disruption due to flooding of the source wells is unlikely to cause a long-
term impact to the remedy because impacted groundwater wells downgradient of the site have been
taken out of service and the Nasonville Water District is the sole source of potable water.
Tarklin brook, located approximately 100 feet West of the RCRA Subtitle C cap for OIJ-II, is located
within a flood plain, however, the base of the RCRA Subtitle C cap is located approximately 14 feet
above the flood stage of Tarklin brook, and the brook is unlikely to pose a significant danger to the
integrity of the cap.
We are unable to draw any conclusions at this time of the impact of climate change on the remedy for
OlJ-111. It is possible that flooding and drought conditions will alter the groundwater elevation,
direction, and flow rate, however, there is not enough data available to conclude if this would impact the
remedy in a meaningful way.
QUESTION B: Are the exposure assumptions, toxicity data, cleanup levels, and
remedial action objectives (RAOs) used at the time of the remedy selection still
valid?
Question B Summary
No. There have been no changes in toxicity values, exposure assumptions, exposure pathways and
methods of evaluating risk, as well as potential standards and TBCs since the 1984, 1989, and 1991
RODs. New information on emerging contaminants including PFAS and 1,4-dioxane is available. The
changes described below do not impact the protectiveness of the remedy because institutional controls
are in place to prevent disturbance of the cap system and prevent use of impacted groundwater.
Changes in Standards and TBCs
New standards (federal or state statutes and/or regulations), as well as new TBC guidances, should be
considered during the Five-year review process as part of the protectiveness determination. Under the
NCP, if a new federal or state statute and/or regulation is promulgated or a new TBC guidance is issued
after the ROD is signed, and, as part of the Five-year review process it is determined that the standard
needs to be attained or new guidance procedures followed to ensure that the remedy is protective of
human health and the environment, then the Five-year review should recommend that a future decision
document be issued that adds the new standard as an ARAR or guidance as a TBC to the remedy.
24
-------
EPA guidance states:
"Subsequent to the initiation of the remedial action new standards based on new scientific
information or awareness may be developed and these standards may differ from the cleanup
standards on which the remedy was based. These new ... [standards] should be considered as part of
the review conducted at least every Five-Years under CERCLA §121(c) for sites where hazardous
substances remain on-site. The review requires EPA to assure that human health and the
environment are being protected by the remedial action. Therefore, the remedy should be examined
in light of any new standards that would be applicable or relevant and appropriate to the
circumstances at the site or pertinent new standards, in order to ensure that the remedy is still
protective. In certain situations, new standards, or the information on which they are based may
indicate that the site presents a significant threat to health or environment. If such information comes
to light at times other than at the Five-year reviews, the necessity of acting to modify the remedy
should be considered at such times." (See CERCLA Compliance with Other Laws Manual: Interim
Final (Part 1) EPA/540/G-89/006 August 1988, p. 1-56.)
PFAS (Federal)
In May 2022, EPA issued updated noncancer reference dose (RfD) values for several PFAS compounds
which result in the following Regional Screening Levels (RSLs) at HQ target 0.1:
• PFOA 6 ng/L
• PFOS 4 ng/L
• PFNA 6 ng/L
• PFHxS 40 ng/L
• HFPO-DA (Gen-X) 6 ng/L
The RfD values for PFOA, PFOS, PFNA and PFHxS are based on Agency for Toxic Substances and
Disease Registry (ATSDR) Minimal Risk Levels (MRLs) for ingestion exposure.
The RfD value for HFPO-DA (Gen-X) is based on a chronic oral RfD from EPA Office of Water which
is 3E-06.
In May 2021, EPA issued an updated noncancer RfD for Pert!uorobutanesulfoni c acid (PFBS). PFBS
has a chronic oral RfD of 3E-04.
In December 2022, EPA released a new oral reference dose (RfD) of 1.0E-03 mg/kg-day for
Perfluorobutanoic acid (PFBA) based on a new IRIS value. Previously, no RfD was available for
PFBA.
In 2023, EPA released a new oral reference dose (RfD) of 5.0E-04 mg/kg-day for Perfluorohexanoic
acid (PFHxA) based on a new IRIS value. Previously, no RfD was available for PFHxA.
PFAS (State)
On January 9, 2019, amendments to Rhode Island Groundwater Quality Rules became effective
including, among other things, groundwater quality standards for PFOA and PFOS of 70 ng/L (ppt)
25
-------
individually or combined, in groundwaters classified as GAA and GA.1 On June 27, 2022, the Governor
of Rhode Island signed a law establishing the sum of six PFAS compounds (pert! uorooctanoi c acid
(PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS),
perfluorononanoic acid (PFNA), pert]uoroheptanoic acid (PFHpA), and pert]uorodecanoic acid (PFDA),
either individually or in combination, as the interim drinking water standard not to exceeds 20 ppt
(PFAS in Drinking Water, Groundwater and Surface Waters Act, H 7233 Substitute A ("Resolution")).
At the time this FYR was written, the RIDEM has not yet promulgated this standard, however it is
expected to by the end of 2023.
At this time EPA has made no determination of whether these new standards will need to be added as
an ARAR for this Site. They should, however, be used as screening values for PFAS compounds,
along with the RSLs.
Although there are multiple exceedances of the current 70 ng/L Rhode Island groundwater quality
standard and the EPA RSL, the remedy remains protective because the alternative water supply and
institutional controls limits exposure pathways to contaminated groundwater. Expanded groundwater
sampling will be conducted for both PFAS compounds and 1,4 Dioxane to better understand nature and
extent of the contamination to better assess potential risk to receptors.
PFAS data has been collected from a series of wells between 2018 and 2022. For purposes of this FYR,
PFAS concentrations are compared to EPA RSLs and state standards. PFOA exceeded the EPA RSL of
6 ppt in 4 out of 18 wells sampled (CMS, C-5S, C-6S, II-3S) between 2018 and 2022. PFOA exceeded
the state standard in 2 out of 18 wells (CMS, C-6S) between 2018 and 2022. Wells CMS and C-6S had
multiple exceedances of PFOA. PFOS exceeded the EPA RSL of 4 ppt in 11 out of 18 wells sampled
(CMD, C-4M, CMS, C-5S, C-6S, I-2B, I-2D, I-2S, I-6B, I-6D, I-8D) between 2018 and 2022. PFOS
exceeded the state standard in 1 out of 18 wells between 2018 and 2022. Wells CMS and C-6S had
multiple exceedances of PFOS.
PFNA exceeded the EPA RSL of 6 ppt in 3 out of 18 wells sampled (CMS, C-5S, C-6S) between 2018
and 2022. PFNA exceeded the state standard in 2 out of 18 wells between 2018 and 2022 (CMS, C-6S).
Wells CMS and C-6S had multiple exceedances of PFN A. PFHxS and PFBS did not exceed screening
levels or standards. No data is available for PFBA or PFHxA.
Detections of PF AS do not alter the current protectiveness of the remedy because ICs are in place which
restrict use of groundwater.
1 GA A is defined as, "those groundwater resources which the Director has designated to be suitable for public drinking water
use without treatment and which are located in.. .Groundwater reservoirs and portions of their recharge area.. .Wellhead
protection areas... [and] physical lv isolated Groundwater dependent areas." Groundwater Quality Rules, Rule 9.1.1. GA is
defined as, "those groundwater resources which the Director has designated to be suitable for public or private drinking water
use without treatment and which arc not described in Rule 9.1.1." Rule 9.1.2 Groundwater Classes G A A and G A arc those
resources that arc suitable for public drinking water use and arc thus to be protected to maintain drinking water.
26
-------
1,4-dioxane
As of the date of this FYR, the State of Rhode Island does not have a MCL or groundwater standard for
1,4-Dioxane. Using 2013 updated IRIS toxicity information and the standard Superfund risk assessment
approach, EPA's carcinogenic risk range of 1 to 10"4 for 1,4-dioxane equates to a concentration range
of 0.46 to 46 |ig/L. 1,4-Dioxane is not currently a COC for this site, and there is not a cleanup goal for
1,4-dioxane.
The 2018-2022 groundwater sampling results for 1,4-dioxane indicate that multiple wells had detections
of 1,4-dioxane exceeding the RSL (0.46 (.ig/L) including C-4D, C-4S, I-2B, I-2D, 1-3D, I-6B, I-6D, I-
8D, and I1-3D. While most detections were within the cancer risk range, one well (1-6B), showed two
detections exceeding 46 (.ig/L (10~4 cancer risk). ICs are in place which restrict use of groundwater.
Therefore, the remedy remains protective of human health and the environment because there is no
completed exposure pathway to the 1,4-dioxane contamination.
Changes in Toxicity and Other Contaminant Characteristics
There have been updates in toxicity values for some of the contaminants that were identified in decision
documents, which are discussed below. Additionally, new information has become available on
emerging contaminants including 1,4-dioxane and PFAS. Although cancer risk and non-cancer hazards
from these contaminants may change due to updates in toxicity values, these changes would not be
expected to alter the protectiveness of the remedy because there is no current exposure to impacted
groundwater and ICs are in place.
2023 PFHxA non-cancer toxicity value
In 2023, EPA released a new oral reference dose (RfD) of 5.0E-04 mg/kg-day for Pert]uorohexanoic
acid (PFHxA) based on a new IRIS value. Previously, no RfD was available for PFHxA. No data is
currently available for PFHx A. However, there are ICs in place which prevent exposure to drinking
water. Therefore, this update does not impact remedy protectiveness.
2022 cis-1,2-Dichloroethylene non-cancer toxicity value
In October 2022, EPA released a non-cancer reference concentration (RfC) of 4.00E-02 mg/m3 for cis-
1,2-Dichloroethylene (Cis-1,2-DCE), based on a PPRTV screening value. Previously, no RfC was
available for Cis-1,2-DCE.
This update does not impact remedy protectiveness because ICs are in place to prevent use of impacted
groundwater.
2022 PFBA noil-cancer toxicity value
In December 2022, EPA released a new oral reference dose (RfD) of 1 0E-03 mg/kg-day for
Perfluorobutanoic acid (PFBA) based on a new IRIS value. Previously, no RfD was available for
PFBA.
27
-------
There is currently no data available for PFBA. However, this update does not impact remedy
protectiveness because groundwater that may be impacted by PFAS contamination is not being used as a
drinking water source, therefore there would not be any current exposure to PFAS in groundwater.
2022 PFOA/PFOS/PFNA/PFHxS 11011-cancer toxicity values
In May 2022, EPA released updated oral reference doses (RfDs) for perfluorooctanoic acid (PFOA),
Pert!uorononanoic acid (PFNA), Pert!uorooctanesulfoni c acid (PFOS), and Perfluorohexanesulfonic
acid (PFHxS), based on the ATSDR Minimal Risk Level (MRL). The new RfDs are as follows:
• PFOA 3x 10"06 mg/kg-day
• PFOS 2x 10"°" mg/kg-day
• PFN A 3xlO"06 mg/kg-day
• PFHxS 2.0xl0"°5 mg/kg-day
These new values indicate that PFOA and PFOS are more toxic from non-cancer health effects and
would result in an increased non-cancer risk. Values for PFNA and PFHxS were not previously
available, but if detected would result in increased non-cancer risk.
Potential estimated health risks from PFOA, PFOS, PFNA, and PFHxS would likely increase total site
risks due to groundwater exposure, however there is no current groundwater exposure at the Site and ICs
are in place. Therefore, this update does not impact remedy protectiveness.
2021 PFBS 11011-cancer toxicity value
In May 2021, EPA released an oral reference dose (RfD) of 3xlO"04 mg/kg-day, based on an EPA
Provisional Peer Reviewed Toxicity Value (PPRTV) (USEPA, 202 la). The new value indicates that
PFBS is more toxic from non-cancer health effects and would result in an increased non-cancer risk.
PFBS did not exceed the EPA screening level. Additionally, there is no current exposure to groundwater
at the Site. Therefore, there is no impact to remedy protectiveness.
2020 Trails-1,2-dichloroetliyleiie 11011-cancer toxicity value
In November 2020, EPA finalized a new reference concentration (RfC) for trans-1,2-dichloroethylene
based on a new PPRTV. There previously was no RfC for trans-1,2-dichloroethylene.
This update does not impact remedy protectiveness because ICs are in place to prevent use of impacted
groundwater.
Lead in Soil Cleanups
EPA continues to examine the science around lead exposure. Updated scientific information indicates
that adverse health effects are associated with blood lead levels (BLLs) at less than 10 |ig/dL. Several
studies have observed "clear evidence of cognitive function decrements in young children with mean or
group BLLs between 2 and 8 (.ig/dL."
Based on this updated scientific information, EPA is including an evaluation of potential lead risks with
a goal to limit exposure to residential and commercial soil lead levels such that a typical (or
28
-------
hypothetical) child or group of similarly exposed children would have an estimated risk of no more than
5% of the population exceeding a 5 |ig/dL blood lead level (BLL). This is based on evidence indicating
cognitive impacts at BLLs below 10 |ig/dL. A target BLL of 5 |ig/dL reflects current scientific literature
on lead toxicology and epidemiology that provides evidence that the adverse health effects of lead
exposure do not have a threshold.
EPA's 2017 OLEM memorandum "Transmittal of Update to the Adult Lead Methodology's Default
Baseline Blood Lead Concentration and Geometric Standard Deviation Parameters" (OLEM Directive
9285.6-56) provides updates on the default baseline blood lead concentration and default geometric
standard deviation input parameters for the Adult Lead Methodology. These updates are based on the
analysis of the NHANES 2009-2014 data, with recommended updated values for baseline blood lead
concentration being 0.6 |ig/dL and geometric standard deviation being 1.8.
Using updated default IEUBK and ALM parameters at a target BLL of 5 |ig/dL, site-specific lead soil
screening levels (SLs) of 200 ppm and 1,000 ppm are developed for residential and
commercial/industrial exposures, respectively.
Given the ongoing review of information, the above SLs are considered in this Five-Year Review for
informational purposes.
Lead was not identified as a COC in the decision documents for the Site; however, as part of the remedy
for OU2, all contaminated soils were excavated and consolidated under a RCRA C impermeable cap.
Additionally, the cap plus its surrounding areas were fenced and posted with warning signs. The cap
remains in place and would prevent exposure to metals including lead; therefore, this update does not
alter the protectiveness of the remedy.
Changes in Risk Assessment Methods
There are no updates on changes in risk assessment methods since the 2018 FYR. Although some risk
methodologies have changed since the time of remedy selection, a review of site information finds that
these changes do not call into question the protectiveness of the remedy. Links to the most recent
updates to the EPA Regional Screening Level tables and Vapor Intrusion Screening Level tables can be
found below.
EPA RSL Updates
Updated twice/year. Use most up-to-date tables as available at:
https ://www. epa. gov/ri sk/regi onal -screeni ng-1 evel s-rsl s-whats-new
EPA VISL Updates
Updated twice/year. Use most up-to-date tables as available at:
https://www.epa.gov/vaporin.tnisioii/visl-whats-iiew
Changes in Exposure Pathways
2021 Development of the Ecological Screening Values (ESVs) for per- and poly-fluorinated alkyl
substances
29
-------
The ecological screening values (ESVs) have been developed to support screening-level ecological risk
assessments sites where per- and poly-fluorinated alkyl substances (PFAS) have been detected in soils
and surface waters. The ESVs, developed for eight PFAS, represent PFAS concentrations in soil and
surface water at or below which chronically exposed biota are not expected to be adversely affected and
ecological risks or other impacts are unlikely.
The ESVs support the screening level steps (Steps 1 and 2 of eight steps) of U.S. Environmental
Protection Agency's Ecological Risk Assessment Guidance for Superfund and may be applied at sites
undergoing investigation for the historic release or disposal of PFAS, to identify whether PFAS levels
pose potential unacceptable ecological risks. Sites that have concentrations of PFAS that exceed ESVs
may require further investigation in a baseline ecological risk assessment, which in turn may support
risk-management decisions and actions to reduce risks. These ESVs are solely for use in conducting
screening-level ecological risk assessments and are not recommended or intended for use as default
cleanup values.
The ESVs were developed for the following media and receptors:
Soils for invertebrates;
Soils for plants;
Soils for avian and mammalian wildlife;
Surface water for freshwater and marine aquatic biota; and
Surface water for aquatic-dependent avian and mammalian wildlife.
(Ecological Screening Values can be found in: (hippo et al, 2021)
Vapor Intrusion and 2018 EPA VISL Calculator
In February 2018, EPA launched an online Vapor Intrusion Screening Level (V1SL) calculator which
can be used to obtain risk-based screening level concentrations for groundwater, sub-slab soil gas, and
indoor air. The VISL calculator uses the same database as the Regional Screening Levels for toxicity
values and physiochemical parameters and is automatically updated during the semi-annual RSL
updates. Please see the User's Guide for further details on how to use the VISL calculator.
https://www.epa.gov/vaporintrusion/vapor-intrusion-screening-level-calculator.
The groundwater data reviewed for the 2018 FYR showed a few concentrations above EPA target
groundwater VOC concentrations for the VI pathway including TCE, PCE, vinyl chloride and 1,1-
dichloroethane, but because there are no potential receptors (e.g., occupants of buildings) in the area
where vapor-forming chemicals are present in the subsurface, the vapor intrusion exposure pathway at
the Site was determined to be incomplete.
Groundwater data was reviewed again for the 2023 FYR. Groundwater data for the period of 2018-2022
indicated TCE, PCE, vinyl chloride exceeded EPA groundwater VISLs. These results are consistent with
the previous FYR. The vapor intrusion pathway remains incomplete because there are no potential
receptors currently.
The implemented remedy addresses the presence of vapor-forming chemicals by reducing contaminant
concentrations through MNA. However, if Site conditions or land use were to change in the future, or if
there is evidence of contaminant migration from the Site towards residences, vapor intrusion may need
to be re-evaluated.
30
-------
Expected Progress Towards Meeting RAOs
uiuuuuuuuuuuiuuuuuuuuuuuuuuuuuuiiuAiwauuuuuuui liiiiiiiiiiiiiui uuuuuuuuuiiuuuiuuuuuuuuumaSiniuuuuuuuuuuuuuuuuuuiuuuuiij
The remedy is progressing as planned toward meeting RAO of the 1991 ROD (OIJ-III) to restore
contaminated groundwater in the contaminated plume zone to state and federal ARARs, including
drinking water standards, and to a level that is protective of human health and the environment as soon
as practical. RAOs for OU-I and OIJ-II have been met. As noted, the presence of emerging contaminants
1,4 Dioxane and PFAS have not been fully investigated and do not have RAOs in the 1991 ROD.
QUESTION C: Has any other information come to light that could call into
question the protectiveness of the remedy?
The expected impacts of climate change in New England pose increasing risks to contaminated sites.
Increases in air and water temperature, precipitation, flooding, and periods of drought may result in
altered fate and transport pathways and exposure assumptions, impaired aquatic habitats, dispersal of
contaminants, damage to remediation related structures, and ultimately ineffective remedies. Increased
frequency of extreme weather events may cause damage or releases at sites, impairing remedial efforts
where remedies have not been adequately designed to protect against these previously unrealized risks.
The risks posed by climate change in New England are not expected to alter the protectiveness of the
remedy at the Western Sand and Gravel site. When the Western Sand and Gravel Superfund site is
compared to FEMA Flood Hazard Zones and EPA Estimated 100-year Floodplains using the Region 1
NPL Vulnerability Assessment tool, although a portion of the site is within a 100 year floodplain, the
RCRA Subtitle C landfill as part of OLJ-11 is located at an base elevation which is well above flood stage
of nearby streams (see Appendix B), and the increasing severity and frequency of storms are unlikely to
cause significant damage to the well maintained cap. While increased frequency and severity of storms
or long periods of drought or flood conditions may impact the vegetative cover of the cap or alter
groundwater elevation, there is no evidence at this time to support a conclusion that permanent damage
to the remedies, or new or accelerated exposure pathways would develop which would significantly
impact or change human risk scenarios.
Changes to land use and surface hydrology, most notably installation of eight infiltration basins/ponds
and pumping activities at the low elevation point at the northeast edge of the property, have occurred at
the adjacent land parcel ("the quarry") in the time since the 2018 FYR was completed. Information
gathered since then suggests the geologic material being removed during quarry operations is often
saturated, indicating close proximity to the groundwater table, and that dewatering activities may be
occuring on the northeast portion of the property and a mixture of storm water and groundwater is being
transported to the infiltration basins on the western edge of the property. It is unclear at this time if these
activities are being performed on a scale that has potential to impact local and regional groundwater
flow, however, it should be noted that the quarry is bounded by the Western Sand & Gravel superfund
site to the west and the L&RR Superfund Site to the northeast, and historic groundwater elevation data
suggests a groundwater divide exists on the quarry property. Therefore, it is conceivable that disruption
to the natural flow regime at the quarry property by pumping, infiltration, or dewatering has the potential
to alter subsurface flow and potentially impact the protectiveness of the remedies at both the Western
Sand & Gravel Superfund site and the L&RR Superfund site. Additional monitoring of site conditions
and groundwater elevation at the Western Sand and Gravel Superfund site should be performed by the
PRP group as outlined in the "Other Findings" section to gain a better understanding of the magnitude of
any changes and to better evaluate potential changes to protectiveness of the remedies.
31
-------
VI.
I ssiics/ Rccoin incniliiI io 11 s
OlJ(s) without Issues/Recommendations Identified in the Five-Year Review:
OU-1
Issues and Recommendations Identified in the Five-Year Review:
OU(s): II
Issue Category: Monitoring
Issue: As ICLs are met, groundwater monitoring for OU-III is being reduced and
wells decommissioned. As a result, the remedy for OU-II is no longer adequately
monitored for break-through or failure.
Recommendation: A sampling and analysis plan shall be developed to monitor
the long-term protectiveness and efficacy of OU-II remedy.
Affect Current
Protectiveness
Affect Future
Protectiveness
Party
Responsible
Oversight Party
Milestone Date
No
Yes
PRP
EPA/State
9/26/2028
OU(s): III
Issue Category: Monitoring
Issue: Presence of emerging contaminants 1,4 Dioxane and PFAS Constituents
Recommendation: Sample and analyze groundwater monitoring wells C-4S/D. 1-
2D. 1-3D. I-6D. I-8D, and 11-3D twice annually for the presence of 1,4 Dioxane.
and monitoring wells C-4S/M/D, C-5, C-6S. I-2B. I-2S/D. I-6S/D. I-8D, and II-3S
twice annually using appropriate U.S. EPA method for reporting required PFAS
constituents in order to better understand the nature and extent of PFAS
contamination on-site. Sampling frequency or method may be altered at the
discretion of the RPM if results show groundwater consistently meets any
applicable MCL or RSL in place or if there are indications of risk to receptors.
Affect Current
Protectiveness
Affect Future
Protectiveness
Party
Responsible
Oversight Party
Milestone Date
No
Yes
PRP
EPA/State
9/26/2028
OTHER FINDINGS
In addition, the following are recommendations that were identified during the FYR which improve
long-term management of the site but do not affect current and/or future protectiveness:
• Stream flow data is no longer required, and collection of flow rate and depth can be discontinued.
Permanent and temporary stream gauges should be removed.
• In order to evaluate and monitor potential impacts resulting from the infiltration, storage, and
dewatering at the adjacent quarry property, the PRP group should closely monitor conditions on-
site and at adjacent properties for evidence of direct impacts such as overland flow, and perform
routine groundwater elevation monitoring at existing monitoring wells and piezometers to better
characterize groundwater elevation and flow direction.
32
-------
VII. PROTECTIVENESS STATEMENT
I'rolccliMMicss Sljilciiicnl(s)
Operable Unit: Protectiveness Determination: Planned Addendum
I Protective Completion Date:
Protectiveness Statement: OU-I implemented a permanent alternative water supply in the form
connection of impacted or potentially impacted homes to a municipal water supply as a means
of permanent source of safe drinking water. The water supply system has been in operation
since September 1994 without significant disruptions or issues. The remedy at OlJ-1 is
protective of human health and the environment.
I'rolccliMMicss Sliilciiicnt(s)
Operable Unit: Protectiveness Determination: Planned Addendum
II Protective Completion Date:
Protectiveness Statement: The remedy at OIJ-II is currently protective of human health and the
environment due to the consolidation of contaminated soil and bulk waste in an on-site RCRA
Subtitle C landfill with an impermeable barrier and liner. To remain protective in the long term,
the following actions should be taken: A sampling and analysis plan shall be developed for
long-term monitoring of the existing groundwater monitoring wells in the vicinity of the RCRA
Subtitle C landfill which is consistent with RCRA landfill monitoring requirements and
adequately monitors the protectiveness and efficacy of OIJ-II remedy.
I'rolccliMMicss Sliilcincnl(s)
Operable Unit: Protectiveness Determination: Planned Addendum
III Short-term Protective Completion Date:
Protectiveness Statement: The remedy for OU-III currently protects human health and the
environment through implementation of various response actions, the placement of institutional
controls on adjacent land parcels, physical barriers to site access, and long-term monitored
natural attenuation of Site COC's with routine statistical analysis. While the monitored natural
attenuation of chlorinated solvents and other VOCs has proceeded as expected and all but two
wells have met site ICLs, the recent discovery of 1,4-Dioxane and PFAS in multiple wells is of
concern. However, as potential receptors are protected by the alternative water source and no
known direct exposure pathways, the presence of PFAS and 1,4-Dioxane at the site are not
believed to significantly impact the protectiveness of the remedy, however, to ensure long-term
protectiveness, sampling and analysis of groundwater monitoring wells C-4S/D, I-2D, 1-3 D, I-
6D, I-8D, and 11-3D should occur twice annually to evaluate the presence of 1,4 Dioxane, and
monitoring wells C-4S/M/D, C-5, C-6S, I-2B, I-2S/D, I-6S/D, I-8D, and II-3S twice annually
using appropriate U.S. EPA method to evaluate the presence of PFAS constituents in order to
better understand the nature and extent of emerging contaminants on-site.
33
-------
Sik'widc Protect ivonoss Slulciiienl
Protectiveness Determination:
Short-term Protective
Planned Addendum
Completion Date:
Protectiveness Statement: The remedies for OU-I and OIJ-II have significantly reduced or
eliminated potential human exposure pathways of site COCs, while the remedy for OU-I 11 has
resulted in a significant reduction in the contaminants of concern in the groundwater, of which
there are very limited potential exposure pathways. However, for the remedy to be protective in
the long-term, the cleanup levels in the 1991 ROD, or clean-up levels which are demonstrated
to be equally protective, must be met to ensure protectiveness of the remedy. The remedy must
also be demonstrated to ensure that emerging contaminants 1,4-Dioxane and PFAS do not post
an unacceptable risk to potential receptors or migrate off-site; and implementation of a sampling
and analysis plan for long-term monitoring of the existing groundwater monitoring wells in the
vicinity of the RCRA Subtitle C landfill which is consistent with RCRA landfill monitoring
requirements to adequately monitor the protectiveness and efficacy of the OU-I I remedy
The next Five-year review report for the Western Sand & Gravel Superfund Site is required Five-
Years from the completion date of this review.
VIII. NEXT REVIEW
34
-------
APPENDIX A - REFERENCE LIST
ATSDR. 2021. Toxicological Profile for Perfluoroalkyls.
https://www.atsdr.cdc.gov/toxprofiles/tp20Q.pdf
EPA 1984. Supcrfund Record of Decision: Western Sand & Gravel Site. Rl. EPA/ROD/RO1-84/006
EPA 1985. Superfund Record of Decision - Remedial Alternative Selection: Western Sand and Gravel Site OU-
II. EPA/ROD/RO 1-85/
EPA. 1988. CERCLA Compliance with Other Laws Manual: Interim Final (Part 1). EPA/540/G-89/006. August
1988.
EPA 1991. Superfund Record of Decisions - Western Sand & Gravel Site OU-III
EPA 1992. First Five-Year Review - Western Sand & Gravel
EPA 1998. Second Five-Year Review - Western Sand & Gravel
EPA 2003. Third Five-Year Review - Western Sand & Gravel
EPA 2008. Fourth Five-Year Review - Western Sand & Gravel
EPA 2013. Fifth Five-Year Review - Western Sand & Gravel
EPA. 2014. Human Health Evaluation Manual, Supplemental Guidance: Update of Standard Default Exposure
Factors Memorandum. OSWER Directive 9200.1-120
EPA. 2017. Transmittal of Update to the Adult Lead Methodology's Default Baseline Blood Lead Concentration
and Geometric Standard Deviation Parameters Memorandum, May 17. 2017. OLEM Directive 9285.6-56.
EPA, 2018. Five-Year Review Report For Western Sand and Gravel Superfund Site
Providence County, Rhode Island. September 26th, 2018.
EPA 2018. Sixth Five-Year Review - Western Sand & Gravel
EPA. 2018. Vapor Intrusion Screening Level (VISL) Calculator. Office of Land and Emergency Management.
Office of Superfund Remediation and Technology Innovation (OSRTI). May 2018.
https://www.epa.gov/vaporintrusion/vapor-intrusion-screening-level-calculator
EPA 2019. OU-III Remedial Action Report Approval. July 23, 2019.
EPA 2020. Hydrogeologic Review of the 2020 Proposed Sampling Plan for the Western Sand & Gravel
Superfund Site in Burrillville. Rhode Island. February 20, 2020.
EPA. 2021. Provisional Peer-Reviewed Toxicity Values for Perfluorobutane Sulfonic Acid (PFBS) and Related
Compound Potassium Perfluorobutane Sulfonate. Office of Research and Development. Center for Public Health
and Environmental Assessment. EPA/690/R-21/001F. 2021.
EPA. 2021. Recommendations on the Use of Chronic or Subchronic Noncancer Values for Superfund Human
Health Risk Assessments Memorandum. May 26. 2021. Office of Land and Emergency Management,
Washington. DC. 2021.
35
-------
EPA. 2021. Human Health Toxicity Values for Hexafluoropropylene Oxide (HFPO) Dimer Acid and Its
Ammonium Salt (CASRN 13252-13-6 and CASRN 62037-80-3) Also Known as "Gen-X Chemicals." Office of
Water. Health and Ecological Criteria Division. Washington. DC. October 2021.
EPA, 2023. Western Sand & Gravel Superfund Website. Retrieved from
https://cumulis.epa.gov/supercpad/cursites/csitinfo.cfrn?id=Q 101233
EPA. Integrated Risk Information System (IRIS). Available at https://www.epa.gov/iris
EPA. Provisional Peer-Reviewed Toxicity Values. Available at https://www.epa.gov/pprtv
EPA. Regional Screening Level Tables. Available at https://www.epa.gov/risk/regional-screening-levels-rsls-
generic-tables
M. Grippo. J. Hayse. I. Hlohowskyj. and K. Picel. 2021. Derivation of PFAS Ecological Screening Values.
Environmental Science Division. Argonne National Laboratory. September 2021.
01 in Corporation, 2019. 2019 Fall Site Inspection Report. Western Sand & Gravel. October 9th, 2019.
01 in Corporation, 2019. 2018 Data Report - Western Sand & Gravel. July 29, 2018
01 in Corporation, 2020. 2020 Fall Site Inspection Report. Western Sand & Gravel. October 8th, 2020.
01 in Corporation, 2020. 2020 Fall Site Inspection Report. Western Sand & Gravel. April 8th, 2020
01 in Corporation, 2021. 2021 Fall Site Inspection Report. Western Sand & Gravel. October 8th, 2021.
01 in Corporation, 2021. 2021 Spring Site Inspection Report. Western Sand & Gravel. April 1st, 2021
01 in Corporation, 2021. 2020 Data Report - Western Sand & Gravel. June 1, 2021
01 in Corporation, 2022. 2022 Fall Site Investigation Report. Western Sand & Gravel. October 7th, 2022.
01 in Corporation, 2022. 2022 Spring Site Inspection Report. Western Sand & Gravel. April 1st, 2022.
01 in Corporation, 2023. 2022 Data Report. Western Sand and Gravel. Burrillville. Rhode Island.
State of Rhode Island. 1991. Declaration of Groundw ater Use Restrictions and Protective Covenants - North
Smithfield 168/00792. August 23rd, 1991.
Wood. 2020. Olin Responses to February 27. 2020 US EPA Comments concerning proposed plan for PFAS and
1.4-Dioxane - Western Sand & Gravel Landfill Superfund Site in Burrillville. Rhode Island. March 9th, 2020.
Wood. 2022. Technical Memo Providing Summary of Sampling and Evaluation of PFAS in Groundw ater.
September 12th, 2022.
Wood Environment & Infrastructure Solutions, Inc., 2018. Eco Assessment for 2018 Western
Sand & Gravel Five-Year Review.
36
-------
Appendix B
Site Maps
Appendix B1
Appendix B1
Appendix B2
Appendix B3
Appendix B4
Appendix B5
.A - Burillville Tax Map
B - North Smithfield Tax Map
- Monitoring Well Locations
- Institutional Controls
- Climate Change Vulnerability Map
- 2023 Aerial Photo
-------
¦ yc»03'g
35
#155
39
#150
\ Burrillville Tax Map
i ¦
IP •-
37
#135
/a*A V fM>
41
#100
f '132-0.4-2
42
#70
132-006'
|P^
#0
45
#99
5
#OFF
Burrillville
'J-1. A'.
#24
WS&G ,
RCRA Sub
Landfill
^0-29 Ai
#0
J/19-Q0I
Ac
#275
12
7 #51 .
#255 8 #235
kTV|? A/'q?31 At$pF
#243 #225
NORTH SMITHFIELD
.149 -0 2 5
5.64>Ac
#25
!" 017
'04.AC-
#0
18
#1820 *
jpafAe
#54
'149-9,19
'
#1802
mm
#1
t
11
Appendix B1-A - Bunillville Tax Map
38
-------
North Smithfield Tax Map
North Smithfield
RCRA SU
Landfill
Burrillville
:
Appendix Bl-B
Appendix Bl-B- North Smithfield Tax Map
39
-------
IX-.UI "Til '.'.VVFD-Il iFii'i'-tl^ld V'i.-kc'iv J ?d.;&'ic¦5C.iASIi?P,«w.lLiuli-».S^" J _-n J L-v-¦:d!JAj 'J'J c t u 11 on.jiVji ¦Jjiioit i-vi 5 'iik'J
Western Sard and Gravel
Burrillville, Rhode Island
Site Map
Legend
4r Historic Monitonng Weli
0. Historic Well Clusters; Cannot Be
Located
ft Monitoring \Afell
+ Piezometer
& Stream Gauge
¥ Stream Sampling Location
~ Town Boundary
Parcel Boundary
~ Capped Area
—t- Fenced Area
Vv^ter
Prepared/Bate JMM 03/17/23
Chected/Date JP 03/17/23
40
-------
Site
Block 7 Lot 5
\ \\
\.w
x ¦. \ \
Prepared/Date EFG 03/26/20
Checked/Date MJM 03/26/20
J
Legend
Si Historic Monitoring Well
® Monitoring Well
Pi ^ometer
Stream Gauge
S7 Stream Sampling Local)on
Q Town Boundary
| Parcel Boundary
CD Gapped Area
a—w- Fenced Area
Water
Institutional Control Areas
Map 132/Lot 6 (Former Block 43 Lot42B)
Map 132/Lot 7 (Former Block 43 Lot 4S)
Map 149/Lot 14 (Former Block 43 Lot 76)
| Sleek 7 Lot 3
'Atestern Sand & Gravel Site - Block 7 Lot
5 & Map 149/Lot 15 (Former Block 43 Lot
50)
Note: BurrlllvJIe Parcel Boundsites provided by the Town
af BuiribiBe Planning Dopaftment on 01/26/2018. Parcel
hourcfaric^ fertile Tpv.'n af Nartn Smith field approximated
based co in formation from the tho latin of North Srrrthfiald
wab GIS. Tcnwn bcunderiira obtained From R!<3 S.
Institutional Control Boundaries based on information
recorded in ExNb* A from three \0 itoc-uments signed and
recorded In 13S1 for the following properties; Lots 43/50 In
BurrllMlle and 7/3 In North Smthlleld: Lot 43M2B n
BurrtlMlle: arte L« 43/76 arri Lot43/4S In BurHSvllle
and Lot 7/3 m North Smlthlleld.
Western Sand and Gravel
Burrillville, Rhode Island
wood
Institutional Control Areas
41
-------
Nasoriville
Glendale
Primrose':
Tarkiln
Climate Change Vulnerability Map
5/2/2023, 1:12:59 PM 1:41,378
0 0,25 0.5 1 mi
FEMA Flood Hazard Zones Regulatory Floodway | 1 j 1 f j f / f
3 1% Annual Chance Flood Hazard NPL Superfund Site Boundaries (EPA Public 2022) - Superfund Site Boundaries 0 0 4 ° ® 1.6 km
¦¦ Earlhstar Goographkis, Esri, HERE, Garmin, SafoGraph. GeoTechnotocper.,
0.2% Annual Chance Flood Hazard |U Area in Estimated Floodplain inc. metim iasa, usgs. epa, hps. ijsda
ArcGIS Web AppBuilder
Maxar Esrl Community Maps Contributors. MassGlS. © OpenStreetMap, Microsoft, Esrl. HERE, Garmin. OafeGraph. GeoTechnologies. Inc. METI/MA3A, U3GS. EPA, I IPC. US Census Bureau. USD A |
42
-------
Western Sand & Gravel Aerial Photo
Spring 2023
RCRA Subtitle C
Landfill
Appendix B5 - Aerial Photo - Spring 2023
43
-------
Appendix C
Data Tables
Table la and lb: VOC Groundwater Analytical Data for Monitoring Wells C-4S and 11-3S
Table 2: Historic VOC Concentrations in Monitoring Wells C-4S and II-3S
Table 3: Historic Total VOC for Select Monitoring Wells
Table 4: Summary of 1,4-Dioxane results
Table 5: Tarklin Brook Stream Gauge Data
Table 6: Summary of PFAS Sampling Results
Table 7: Number of wells Impacted by Indicator Compounds and Number Greater than MCL
Table 8: Spring 2018 VOC and 1,4 Dioxane Sampling Event for select monitoring wells
Figure C-9: 1,4-Dioxane in Groundwater Box Plot
Figure C-10: PFAS in Groundwater Box Plot
44
-------
Table 1-a
VOC Groundwater Analytical Data - Well C-4S 2018-2022
Western Sand and Gravel
Burriltvllle, Rl
Location
C-4S
C-4S
C-4S
C-4S
C-4S
C-4S
C-4S
C-4S
C-4S
C-4S
Sample Date
4/2/2018
10/17/201S
4/1/2019
10/1/2019
12/12/2019
9/22/2020
4/7/2021
9/29/2021
4/11/2022
10/20/2022
Sample ID
C-4S PDB
C-4S PDB
C-4S PDB
C-4S PDB
C-4S PDB
C-4S PDB
C-4 S PDB
C-4S PDB
C-4S PDB
C-4S
QC Code
FS
FS
FS
FS
FS
FS
FS
FS
FS
FS
Class
Parameter
Units
ICL
Result Q
Result Q,
Resu ft Q
Result Q,
Result Q
Resu It Q
Result Q.
Result O
Resu It Q.
Result Q.
VOCs
1,1,1 Trichloropthane
UG/L
200
20
VOC s
1,1,2,2-Tet rac h loroetha ne
UG/L
1
0.1 U
VOCs
1,1,2-1 richloroethane
UG/L
3
0.1 U
VOCs
1,1-Dichloroethane
UG/L
3,500
12
VOCs
1,1-Dichloroetliene
UG/L
7
0.2 J
VOCs
1,2 Dichlorobcnzene
UG/L
600
0.1 U
VOCs
1.2 Dichloroet ha no
UG/L
5
0.1 U
VOCs
1.4 Diclilorobenzene
UG/l
75
0.1 U
VOCs
Benzene
UG/l
5
0.1 LI
VOCs
Bromomethane
UG/l
35
0.1 U
VOCs
Clilorobenzene
UG/L
100
0.1 U
VOCs
Chloroethane
UG/L
14,000
0.5 J
VOCs
Chloroform
UG/L
100
0.41
VOCs
Clilofometlidne
UG/L
3
0.2 U
VOCs
cis 1,2 Dichloroethene
UG/L
70
36
VOCs
Ethylbcnzene
UG/L
700
0.3 1
VOCs
Methylene chloride
UG/L
5
0.2 1
VOCs
Tet rac h lo roet he n e
UG/L
5
1.4
0.6
0.1 J
16
11
3.3
2.6
0.61
16
VOCs
Toluene
UG/L
1,000
0.5 J
VOCs
trans-l,2-L)ichloroethene
UG/L
?0
0.1 J
VOCs
trdris-l,3-Dichloiopropene
UG/L
5
0.1 U
VOCs
Trichloroethene
UG/L
5
1.1
0.2 J
0.7
5.2
2.7
VOCs
Trichbrofluoromethdrie
UG/L
10,000
0.1 LI
VOCs
Vinyl chloride
UG/L
2
0.1 1
VOCs
Xylene, o
UG/L
10,000
4.6
VOCs
Xylenes (m&p)
UG/L
10,000
3.3
VOCs
Xylenes, lotal
UG/L
10,000
7.9
Notes and Abbreviations:
ICL: Interim Cleanup Level ug/L: micrograms per liter
J: estimated concentration U: not detected above the repotting limit
1. Yellow shading indicates that the detected concentrations ot chemicals ot concern (COQ forthe most recent eight rounds of sampling are at or below Ids or that the COC
were not detected in any ot the most recent eight sampling rounds for this well.
L Green shading indicates that compliance was previously demonstrated loi the specified COC in the; well with the use of the Groundwater Statistics Tool developed by U5EPA
3. Blue shading indicates that the detected concentration of the specified COC is above the ICL and compliance could not yet be demonstrated
4. No color shading indicates detected concentrations of the COC are not above the ICL or the COC was not detected and the reporting limit is below the ICL.
Prepared by: JPK 2/6/2023
Checked by: CP 2/8/2023
45
-------
Table 1-b
VOC Groundwater Analytical Data - Well II-3S 2018-2022
Western Sand and Gravel
BurrllMlle, Rl
Location
II-3S
II-3S
II-3S
II 3S
II-3S
II-3S
II-3S
II-3S
II-3S
II-3S
Sample Date
4/2/2018
10/17/2018
4/1/2019
10/2/2019
12/12/2019
9/23/2020
4/7/2021
9/29/2021
4/11/2022
10/20/2022
Sample ID
II-3S PDB
II-3S PDB
II-3S PDB
II-3S LF
II-3S LF
II-3S PDB
11-35 PDB
II-3S PDB
II-3S PDB
II-3S PDB
QC Code
FS
FS
FS
FS
FS
FS
FS
FS
FS
FS
Class
Parameter
Units
ICL
Result Q
Result Q
Result Q
Result Q
Result Q.
Result Q
Result Q
Result Q
Result Q
Result Q,
VOCs
'1,1,1 Triehloroethane
UG/L
200
1.8
VOCs
1,1,2,2-T etrachloroethane
UG/L
1
0.1 U
VOCs
1,1,2 - T ric hloroethane
UG/L
3
0.1 U
VOCs
1,1-Dic hloroethane
UG/L
3,500
2.5
VOCs
1,1-Dichloroethene
UG/L
7
0.1 J
VOCs
V-Dichlorobenzene
UG/L
600
0.1 U
VOCs
1,2-Dichloroethane
UG/L
5
0.1 U
VOCs
1,4- Die hloro benze ne
UG/L
75
0.1 U
VOCs
Benzene
UG/L
5
0.1 U
VOCs
Bromomethane
UG/L
35
0.1 U
VOCs
Chloiobeiwene
UG/L
100
0.1 U
VOCs
C hloroethane
UG/L
14,000
0.1 U
VOCs
Chloroform
UG/L
100
0.1 U
VOCs
Chloromethane
UG/L
3
0.2 U
VOCs
cis-l,2-Dichloroethene
UG/L
70
5.3
VOCs
Lthylbenzene
UG/L
/OO
0.1 U
VOCs
Methylene chloride
UG/L
5
0.2 U
VOCs
Tet r ac h lo roet he ne
UG/L
5
0 .4 J
1.8
0.5 U
24
1.6
3.1
0.37 J
0.49 J
0.5 IJ
2.4
VOCs
Toluene
UG/L
1,000
0.1 U
VOCs
trans- 1,2-Dichloroethene
UG/L
/o
0.1 U
VOCs
trans-l,3-Dk.hk)Fopiopene
UG/L
5
0.1 U
VOCs
Irichloroethene
UG/L
5
0.1 J
VOCs
Trichlorotluoromethane
UG/L
10,000
0.1 IJ
VOCs
Vinyl chloride
UG/L
2
0.1 U
0.08 LJ
0.5 U
36
9.3
37
0.5 U
0.5 U
0.5 U
23
VOCs
Xylene, o
UG/L
10,000
0.1 U
VOCs
Xylenes (m&p)
UG/L
10,000
0.1 U
VOCs
Xylenes, lotal
UG/L
10,000
0.1 J
Notes and Abbreviations:
ICL: Interim Cleanup level ug/l: micrograms per liter
J: estimated concentration U: not detected above the reporting limit
1. Yellow shading indicates that the detected concentrations of chemicals of concern (COC) for the most recent eight rounds ot sam pling are at or below IQs or that the
COC were not detected in any of the most recent eight sampling rounds for this well.
2. Green shading indicates that com pliance was previously demonstrated for the specified COC in the well with the use of the Groundwater Statistics lool developed by UStPA
3. Blue shading indicates that the detected concentration of the specified COC is above the ICl and com pliance could not yet be demonstrated
4. No color shading indicates detected concentrations of the COC are not abovethe ICl or the COC was not detected and the reporting limit k below the ICL
Prepared by: JPK 2/5/2023
Checked by: CF 2/8/2023
46
-------
Table 2: Historic VOC Concentrations in Monitoring Wells C-4S and II-3S
II-3S
C-4S
PCE
TCE
vc
PCE
TCE
VC
4/1/2013
0.71
40
9.7
8.1
190
9/1/2013
13
0.1
0.87
13
2.3
0.1
4/1/2014
2.4
0.91
0.49
0.1
0.1
0.1
9/1/2014
3
0.1
0.1
1.8
0.1
0.1
4/1/2015
0.96
0.34
0.1
0.1
0.1
0.1
10/1/2015
0.52
0.1
0.1
0.63
0.1
0.1
3/1/2016
7.2
3
32
14
3
1.7
9/1/2016
0.1
0.1
0.1
0.1
0.1
3/1/2017
7.9
5.6
0.2
40
8.2
0.1
9/1/2017
11
1.5
0.1
4.9
0.8
0.1
4/2/2018
0.4
0.1
0.1
1.4
5
0.1
10/17/2018
1.8
0.1
0.08
0.6
1.1
0.1
4/1/2019
0.5
0.1
0.5
0.1
0.2
0.1
10/2/2019
24
0.1
36
42
0.7
0.1
12/12/2019
1.6
0.1
9.3
16
5.2
0.1
9/23/2020
3.1
0.1
37
11
2.7
0.1
4/7/2021
0.37
0.1
0.5
3.3
0.1
0.1
9/29/2021
0.49
0.1
0.5
2.6
0.1
0.1
4/11/2022
0.5
0.1
0.5
0.61
0.1
0.1
10/20/2022
2.4
0.1
23
16
0.1
0.1
47
-------
Table 3: Historic Total VOC for Select Monitoring Wells
C-4S
II-3S
I-3M
I-3D
C-5S
C-5M
Apr 2007
4194
512.0
13.1
NS
25.8
42.4
Oct 2007
194.5
91.0
2.3
1.5
101.4
26.8
Mar 2008
746.0
99.4
BDL
2.3
66.7
BDL
Sep 2008
67.5
104.3
2.1
2.3
77.3
159.4
Oct 2009
42.3
113.9
3.4
2.6
124.7
51.3
Jul 2010
186.3
238.4
3.9
2.0
17.7
BDL
Oct 2010
81.5
201.8
7.2
1.7
155.5
0.4
Mar 2011
26.0
13.0
BDL
1.1
BDL
0.2
Sep 2011
290.0
205.5
1.0
1.1
15.5
0.5
Mar 2012
494.0
246.2
2.7
2.6
3.4
BDL
Sep 2012
24.9
53.1
BDL
2.9
179.8
BDL
Apr 2013
1201.4
477.3
0.8
2.4
38.4
0.3
Sep 2013
112.6
151.7
BDL
30.3
BDL
Apr 2014
2.2
32.7
BDL
24.1
1.6
Sep 2014
7.9
13.4
BDL
26.5
BDL
Apr 2015
0.5
16.1
1.7
BDL
0.3
Oct 2015
1.8
3.0
BDL
67.6
0.5
Mar 2016
54.7
177.8
BDL
94.8
0.7
Sep 2016
1.2
5.0
BDL
131.8
0.8
Mar 2017
161.7
143.6
2.5
79.3
1.0
Sep 2017
20.6
46.2
0.2
44.5
1.5
Apr 2018
56.2
10.2
BDL
NS
0.8
1.5
Oct 2018
0.8
1.8
0.5
Apr 2019
0.8
BDL
Oct 2019
47.2
60.0
Dec 2019
18.7
10.9
Sep 2020
11.0
40.1
NS
NS
NS
Apr 2021
3.3
0.4
Sep 2021
2.6
0.5
Apr 2022
0.6
BDL
Oct 2022
16.0
25.4
NS - Not Sampled/Sampling Discontinued
BDL - Below Detection Limit
48
-------
Table 4
SUMMARY OF 1,4-DIOXANE SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURR1LLVILLE, RHODE ISLAND
Sampling Event
1/2-3,24/2018
10/16-17/2018
1/1-2/2019
9/10-11/2019
9/11/2019
10/1-2/2019
9/22-23/2019
4/28/2021
9/28-29/2021
10/14/2021
10/19-20/2022
Sample Type
FS
FS
FS
FS
PS
FS
FS
FS
F5
FS
FS
Location
Parameter
C-1D
1,4-Dioxane
-
< 0.02D
-
-
-
-
-
-
C-4D
1,4-Dioxane
4.9
2.9
8.4
-
-
0.80
0.76
-
--
0.45/0.51
0.076
C-4S
1,4-Dioxane
-
-
2-1
-
-
0.20
< 0.020
-
4.9
-
0.44
C-5D
1,4 Dioxcifie
* 0.020/^0.020
t 0.020
< 0.020
C-6S
1,4-Dioxane
-
-
-
-
-
<0,020
-
-
-
T-2B *
t,4-Dioxane
-
12
-
40
31/30
43
-
19
-
15
depth sampled
124-1291 bjs
loe.y-m.s1 bToc
120'-12 5" bTOC
122'bTOC
122' bTOC
122' bTOC
I-2D
1,4-Dioxane
0.18
<0.020
0.50
-
0.36
0.49
-
0.29/0.33
< 0.032/<0.032
I-2S
1,4-Dioxane
-
< 0.020
< 0.020
-
-
-
-
-
~
1-3D
1,4-Dioxane
28
43
32
33
43
-
26
24
I-3S
1,1-Dioxane
-
--
< 0.020
-
-
-
-
-
-
-
I-4D
1,4-Dioxane
-
-
< 0.020
-
-
-
-
-
I-4S
1,4-Dioxane
-
--
< 0.020
-
-
-
-
-
-
-
I-6B*
1,1-Dioxane
-
82
-
50
3.9
4.5
-
4,0
-
4.7
depth sampled
11S' I2C bus
115.5-120.5' blOC
94.5-99.5' bTOC
118' bTOC
118' broc
118' bTOC
I-6D
1,4-Dioxane
0.12/0.15
0.37/0.36
0.S2/O.77
-
2-8/3.2
3.3/3.5
-
2.9
-
0.16
I-6S
1,4-Dioxane
-
< 0.020
<0.020
-
-
-
-
-
-
I-7D
l,4-Dk>xane
< 0.020
-
-
T-8D
1,4-Dioxane
-
~
-
-
--
-
1.1 J/1.4 1
1.4
-
1.7
II-3D
1,4-Dioxane
1.3
1.5
1.1
-
1.0
1.5
-
0.60
1,1
n 3S
1,4-Dk>xane
< 0.020
Notes:
All units in ppb (micrograms per liter).
All cells with two values represent data with field duplicate results —parent sample/field duplicate
Not sampled = — FS = Field Sample J = estimated concentration based upon QC data
Not detected above method detection limit (MDL) =
-------
Table 5
Tarklin Brook Stream Data (2018-2022)
Date Measured
Apr-18
Sep-18
Mar-19
Sep-19
Mar-20
Sep-20
Mar-21
Sep-21
Mar-22
Sep-22
Gauge
SG-1
255,15
255.23
254.81
254.05
254.35
253.85
D
D
D
R
SG-2A
252.68
1.86
253.56
252.26
252.45
252.43
252.50
253.28
253.68
S6-2
252,68
1.26
253.14
2.52.68
252.87*
252.65*
252.86
F
253.34
252.30
SG-3
252.19
0
253,10
O
252.87
251.82
252.32
252.32
253.68
253.70
Notes:
* -no measurable water-number is to mud surface
Q = Overgrown—unable to see stream gauge to read
F = Area flooded—unable to get close enough to read
D= Gauge damaged
R = Repair completed but riot yet re-surveyed
50
-------
Table 6
SUMMARY OF PFAS SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
Sampling Event
4/2/2018
-1/28/2018
2018-10
2019-01
2019-09
2019-09
2019-10
2020-09
2021-04
2021-09
2022-10
Result Unit
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nn/L
nq/L
nq/L
C-1D
N-ethyl pcrtluorooctancsulfonamidoacetic acid (NEtFOSAA)
-
< 2.8
-
-
-
-
N-methyl perfluorooctanesulfonamidaacetic acid (NMeFOSAA)
-
< 2,8
-
—
-
~
-
Perfluorobutanesulfonate (PFDS)
<0.93
-
~
-
Perfluorodecanoic arid (PFDA)
-
< 1.9
--
-
-
-
-
Perfluorododecanok: acid (PF-DoA)
-
< 1.9
-
-
-
--
-
-
-
Perfluoroheptanoic acid (PFHjjA)
<0.93
Perfluorohexanesulfonate (PFHxS)
< 1.9
--
Perfluorohexanoic acid (PFHxA)
< 1.9
-
-
-
-
-
Perfluorononanoic acid (PFNA)
-
< 1.9
-
-
-
-
-
-
-
Perfluoro-octanesulfonate (PFOS)
-
< 1.9
-
-
-
-
Perfluorooctanoic acid (PFOA)
--
<0.93
-
-
-
--
-
-
Perfluorotetradecanoic acid (PFTA)
-
<0.93
-
-
-
-
-
-
--
Perfluorotridecanolc acid (PITrDA)
-
<0.93
-
-
—
-
-
-
PerfluormindecanQic. acid (PFllnA)
-
< 1.9
-
-
-
-
-
C-4D
N ethyl perfluoroocUinesulfonarnldoacetk: acid (NEtFOSAA)
<2.8
N-methyl perflijorooctanesulfonamidoacetlc acid (NMef~0SAA)
-
<2.8
—
-
--
Perfluorobutanesulfonate (PFBR)
-
<0.94
-
-
-
-
-
Perfluorodecanoic acid (PbL)A)
-
< 1.9
--
-
-
-
Perfluorododecanok; acid (PFDoA)
< 1.9
Perfluoroheptanoic acid (PFHpA)
-
2.2
—
-
—
Perfluorohexanesulfonate (PFHxS)
-
-
-
2.5
-
-
-
-
Perfluorohexanoic acid (PFHxA)
-
-
2.4
-
-
-
Perfluorononanoic acid (PFNA)
-
-
--
< 1.9
-
-
-
--
-
--
Perfluoro-octanesultDnate ( PFOS)
-
5.7
«
-
-
-
-
Perfluorooctanoic acid (PPOA)
4.3
Perfluorotetradecanoic arid (PrTA)
-
<0.94
-
-
--
Perfluorotridcicanoic acid (PFTrDA)
-
-
<0.94
-
-
-
--
Perfluoroimdeuinofc acid (PRJnA)
< 1.9
C-4M
N-ethyl perfluarooctanesuifonamidoacetk: acid (NEtFOSAA)
-
--
--
< 2.8
-
N-methyl perfluorooctanesulfortarradoacetic acid (NMeFOSAA)
-
--
-
< 1.9
-
-
PerfluorobuUinesiilfoiidle (PFBS)
< 1.9
Perfluorodecanoic acid (PFDA)
< 1.9
-
-
Perfluorododecanok: acid (PFDoA)
-
-
-
< 1.9
-
-
-
Perfluoroheotanoic acid (PrilpA)
-
-
< 1.9
-
-
Perfluorohexanesulfonate (PFHxS)
-
-
-
--
7.7
-
-
-
Perfluorohexanoicacid (PFHxA)
-
-
< 1.9
-
~
Perfluorononanoic acid (PFNA)
< 1.9
Perf luor o -o ctanes ulfo nate (Pros)
-
-
4.7
-
-
-
-
Perfluorooctanoic acid (PFOA)
-
—
...
2.3
-
-
-
Perfluorotetradecanoic acid (Phi A)
-
-
< 1.9
~
Perfluorotridecanolc acid (PFTrDA)
< 1.9
Perfluoroundecanok acid (PFUnA)
-
-
-
-
-
-
< 1.9
-
-
-
-
Page 1 of 7
51
-------
SUMMARY OF PFAS SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
Sampling Event
•1/2/2018
4/28/2D18
2018-10
2019-01
2019-09
2019-09
2019-10
2020-09
2021-04
2021-09
2022-10
Result Unit
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
C-4S
N-ethyl pertluarooctanesulfonamidoacctic acid (NEtFOSAA)
<2.B/<2.7
<2.7/<2.9
< 2.8/<2.8
< 2.9
-
-
< 2.8
< 2.9
-
< 2.8
< 2.9
N-methyl perfluorooctanesulfanamidoacetic acid (NMeFOSAA)
<2.8/<2.7
<2.7l<2.9
< 2.8/ <2.8
< 2.9
-
-
< 1.9
< 1.9
—
< 1.8
< 1.9
Perfluorobutanesulfonate (Pr3S)
< 0,92/<0.9Q
<0.92/<0.%
< 0.93/<0.95
<0.98
-
< 1.9
< 1.9
< 1.8
< 1.9
Perfluorodecanolc acid (PFDA)
12/12
33/35
19/20
9.1
< 1.9
< 1.9
6.7
< 1.9
Perfluorododecanoic acid (PFDoA)
<0.92/<0.90
<0.92/<0.96
< 1.9/<1.9
< 2.0
-
-
< 1.9
< 1.9
—
< 1.8
< 1.9
Perfluoroheptanoic acid (PFHpA)
<1.8/1.9
740/720
170/180
160
-
-
2.9
< 1.9
-
85
14
Perfluorohoxa nesulfonate (PFHxS)
<1.8/1.8
<1.8/1.9
<1.9/1.9
< 2.0
-
--
< 1.9
< 1.9
--
< 1.8
< 1.9
Perfluorohexanoic acid (PFHxA)
190/180
330/360
130/130
120
—
—
2.6
< 1.9
—
63
8.5
Perfluorononanoic acid (PFNA)
62/62
130/130
56/58
63
-
-
2.4
< 1.9
-
26
4.3
Perfluoro-octanesulfonate (PFOS)
6.4/6.9
10/9.7
7.3/8.5
7.2
-
-
< 1.9
< 1.9
-
4.4
4.6
PerfluoroQCtanoic acid (PFOA)
770/290
6?0/6R0
190/190
210
-
~
4.2
1.9
-
110
16
Perfluorotetradecanoic acid (PFIA)
<0.92/<0.90
<0.92/<0.96
< 0.93/<0.95
< 0.98
< 1.9
< 1.9
< 1.8
< 1.9
Perfluorotridecanoic acid (PFTrDA)
<0.92/<0.90
<0.92/<0.96
< 0.93/<0.95
<0.98
< 1.9
< 1.9
< 1.8
< 1.9
Perfluoroundecanolc acid (PRJnA)
1.9/2.0
4.6/4.8
< 1.9./<1.9
< 2.0
-
~
< 1.9
< 1.9
—
< 1.8
< 1.9
C-5S
N-ethyl perfluorooctariesulforiarnidoacetic acid {NEtFOSAA)
-
-
~
-
-
< 2.8
-
...
N methyl perfluorooclanesuirorkmiidaiicelic acid (NMeFOSAA)
< 1.9
Perfluorobutanesulfonate (PFBS)
-
-
-
-
—
-
< 1.9
-
-
Peifluorodecanoic acid (PFDA)
-
-
~
~
--
-
< 1.9
-
-
~
Perfluorododecanoic acid (PFDoA)
~
-
-
-
-
-
< 1.9
-
-
-
-
Perfluoroheptanoic acid (PFHpA)
-
-
-
--
--
-
4.3
-
-
-
Perfluorohexariesulfonate (PFHxS)
-
-
-
-
-
< 1.9
-
-
Perfluorohexanolc acid (PFHxA)
3.5
Perfluorononanoic acid (PFNA)
--
-
--
--
-
13
~
—
-
Perfluoro-octanesulfonate (PFOS)
-
-
-
-
-
-
7.3
—
-
-
-
Perfluorooctanoic acid (PFOA)
13
Perf luorotetradecano Ic add (PFFA)
< 1.9
Perfkiorotridecanoic acid (PFTrDA)
-
—
«
-
-
< 1.9
—
-
Perfluoroiindecanoic acid (PFUnA)
-
-
--
--
-
< 1.9
«
-
-
C-6D
N-ethyl pertluorooctancsulfonamidoacctic acid (NEtFOSAA)
-
~
-
< 2.7/<2.7
-
-
—
—
—
-
N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
-
-
-
< 2.7/<2.7
~
-
-
-
—
-
Perfluorobutanesulfonate (Pros)
-
-
~
< 0.69/<0.89
-
-
—
-
-
-
-
Perfluorodficanoic arid (PFDA)
-
-
< 1.8/<1.8
-
-
—
»
-
-
--
Perfluorododecanoic acid (PFDoA)
-
--
< 1.8/<1.8
-
-
-
-
~
PerfluoroliepUinuic ackl (PFHpA)
< 0.89/0.89
Perfluorohexar>esulfonate (PnixS)
-
-
< 1.8/<1.8
-
-
—
-
-
--
Perfluorohexarwic acid (PFHxA)
-
—
--
< 1.8/<1.8
--
-
-
—
-
Perfluorononanoic acid (PFNA)
-
—
-
< 1.8/<1.8
-
—
—
—
-
-
Perfluoro octanesulforwle (PFOS)
< 1.8/<1.8
Perfluorooctanoic acid (PFOA)
-
—
1.2/1.3
~
-
-
-
~
Perfluorotetradecanoic acid (PFTA)
-
-
< 0.89/<0.89
~
-
-
-
-
-
Perfluorotridecanoic acid (PFTrDA)
-
-
-
< 0.89/ <0.89
-
-
—
-
...
Perfluoroundecanoic acid (PRJnA)
-
-
< 1.8/<1.8
--
-
-
-
-
Page 2 of 7
52
-------
SUMMARY OF PFAS SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
Sampling Event
1/2/2018
1/28/2018
2018-10
2019-01
2019-09
2019-09
2019-10
2020-09
2021-01
2021-09
2022-10
Result Unit
nq/L
na/L
na/L
na/L
na/L
na/L
na/L
na/L
na/L
na/L
na/L
C-6M
N-ethyl perHuorooctanesulfanamidoacetic acid (NEtFOSAA)
-
<2.8
-
N-methyl perfluorooctanesulforHrnidoacetic acid (NMeFOSAA)
-
-
-
--
-
< 1.9
-
-
-
Perfluorobutanesulfonate {PFDS)
-
-
-
< 1.9
...
Perfluorodecanoic arid (PFDA)
~
-
-
-
-
< 1.9
--
-
Perfluorododecanoic acid (PFDoA}
-
-
—
< 1.9
-
-
Perfluoroheptunoic acid (PFHpA)
< 1.9
Perfluorohexanesulfonate (PFHxS)
<1.9
Perfluorohexanoic acid (PFHxA)
~
-
-
< 1.9
-
Perfluorononanoic acid (PFNA)
-
-
< 1.9
-
-
Perfluoro-octanesulforwte (PFOS)
-
< 1.9
--
Perfluorooctanoic acid (PFOA)
—
-
-
< 1.9
-
-
Perfluorotetradecanoic acid (PFTA)
-
-
< 1.9
-
Perfluorotridecanolc acid (PrTrDA)
--
-
-
< 1.9
--
-
Perfluoroundecanoic acid (PFUnA)
-
< 1.9
-
C-6S
N ethyl perfluorooctonesulfonarnidoacetk: acid (NEtFOSAA)
<2.7
<2.8
< 2.9/<2.8
<2.8
<2.6/<2.7
N-methyl perfluorooctanestilfonamidoacetir acid (NMeroSAA)
-
<2.7
-
-
< 1.9
< 1.9/<1.9
-
2.6
<1.7/<1.8
Pftrfluorobutanesulfonate (PFRS)
-
< 0.91
< 1.9
< 1.9/<1.9
-
< 1.9
<1.7/
-------
SUMMARY OF PFAS SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
Sampling Event
•1/2/2018
4/2B/2018
2018-10
2019-0-1
2019-09
2019-09
2019-10
2020-09
2021-04
2021-09
2022-10
Result Unit
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
I-2D
N-ethyl pcrfluorooctanesulfonamidoacetic. acid (NEtFOSAA)
~
-
< 2.9
-
—
--
N-methyl perfluorooctanesulforianiidoacetic acid (NMeFOSAA)
-
< 2.9
—
-
Perfluorobutanesulfonate (PFBS)
-
-
0.97
—
-
Perfluorodecanoic arid (PFDA)
-
-
< 1.9
—
~
—
-
Perfluorododecanoic acid (PFDoA)
-
-
~
< 1.9
—
—
—
-
-
Perfluoroheptarioic acid (PI-HyA)
1.9
Perfluorohexanesulfonate (PRtxS)
4.1
Perfluorohexanoic acid (PFHxA)
--
~
< 1.9
—
—
--
Perfluorononanoic acid (PFNA)
-
-
< 1.9
-
~
—
-
Perfluoro-o cranes ulfonate (PFOS)
-
-
7.5
-
—
—
Perfluorooctanoic acid (PFOA)
~
--
2.9
—
~
—
Perfluorotetradecanoic acid (PFTA)
-
-
< 0.95
—
-
-
Perfluorotridecanoic acid (PrTrDA)
-
-
<0,95
-
—
--
Perfluoroundecanoic acid (PRJnA)
-
-
< 1.9
-
—
—
-
£-25
N ethyl perfluorooctaiiebulfonamldoacetk; acid (NEtFOSM)
< 2.8
< 2.9
< 2.7
< 2.8
N-methyl perfluorooctanesulforwmJdoacetic acid (NMeroSAA)
-
-
< 2.8
-
-
—
< 1,9
-
< 1.8
< 1.9
Perfluoroblltanesulfonate (PFBS)
-
~
<0.94
-
—
< 1.9
-
< 1.8
< 19
Perfluorodecanoic acid (PFDA)
-
-
< 1.9
-
-
--
—
< 1.9
< 1.8
< 1.9
Perfluorododecanoic acid (PFDoA}
< 1.9
< 1.9
< 1.8
< 1,9
Perfluoroheptanoic acid (PFHpA)
-
-
1.6
-
C 1.9
-
< 1.8
< 1.9
Perfluorohexanesulfonate (PFHxS)
-
-
4.6
—
2.6
—
4,9
2.5
Perfluorohexanoic acid (PFHxA)
2.2
—
< 1.9
—
< 1.8
< 1.9
Perfluorononanoic acid (PFNA)
--
-
< 1.9
-
—
< 1.9
—
< 1.8
< 1.9
Perfluoro-octanesulfonate (PFOS)
-
6.2
—
5.0
—
5.8
6.3
Perfluorooctanoic acid (PFOA)
<0.94
< 1.9
< 1,8
< 1.9
Perfluorntetradecannir: arid (PITA)
--
-
< 0.94
-
—
< 1.9
-
< 1.8
< 1.9
Perfluorotridoranoic acid (PFTrDA)
-
-
<0.94
—
< 1.9
-
< 1.8
< 1.9
Perfluoroundecanoic acid (PFUnA)
< 1.9
< 1.9
< 1.8
< 1.9
1-35
N-ethyl perfluoroDctanesLitfanamidoacetk: acid (NEtFOSAA)
-
-
< 2.7/<2.6
< 2.8
-
< 3.D
< 2.8
N-methyl peifluoiooctanesLilfonarrndoacetic acid (NMeFOSAA)
-
-
< 1.8/---: 1,7
< 1.9
—
< 2.0
< 1.9
PerfluorobuLanesdfonciU; (PFBS)
< 1.8/<1.7
< 1.9
< 2.0
< 1.9
Perfluorodecanoic acid (PFDA)
»
-
-
< 1.8/<1.7
< 1.9
-
< 2.0
< 19
Perfluorododecanoic acid (PFDoA)
-
-
< 1.8/<1.7
< 1.9
—
< 2.0
< 1.9
Perfluoroheptanoic acid (PRIpA)
-
-
< 1.8/<1.7
< 1.9
—
< 2.0
< 1.9
Perfluorohexanesuifonate (PFHxS)
«
--
< 1.8/<1.7
< 1.9
—
<2.0
< 1.9
Perfluorohexanoic acid (PFHxA)
-
-
< 1.8/<1.7
< 1.9
-
2.0
< 1.9
Perfluorononanoic acid (PFNA)
< 1.8/<1.7
< 1.9
<2.0
< 1,9
Perfluoro-octanesulfonate (Pros)
-
-
-
-
< 1.8/< 1.7
< 1.9
—
<2.0
< 1.9
Perfluorooctanoic ac:id (PFOA)
~
-
-
< 1.8/< 1.7
< 1.9
—
2.2
< 1.9
Perfluorotetradecanoic acid (PFIA)
-
< 1.8/<1.7
< 1.9
—
< 2.0
< 1.9
Perfluorotridecanoic acid (PFTrDA)
< 1.8/<1.7
< 1.9
< 2.0
< 1.9
Perfluoroundecanoic acid (PFUnA)
-
-
< 1.8/<1.7
< 1.9
-
< 2.0
< 1.9
Page 4 of 7
54
-------
SUMMARY OF PFAS SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
Sampling Event
•1/2/2018
4/28/2018
2018-10
2019-01
2019-09
2019-09
2019-10
2020-09
2021-0/l
2021-09
2022-10
Result Unit
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
I-6B*
115 -120" bqs
94.5 -99.5' bTOC
115.5 -120.5" bTOC
N-cthyl pcrtluorooctancsulfonamidoacctic acid (NEtFOSAA)
—
< 3.7
-
<2.8
<2.8
—
~
—
-
N-methyl perfluorooctanesulforamidaacetic acid (NMeFOSAA)
—
< 3.7
-
<1.8
<1.8
—
-
-
-
Perfluorobutanesulfonate (PFBS)
< 1.2
<1.8
<1.8
—
-
—
Perfluorodecanoic arid (PFDA)
~
< 2,5
-
<1.8
<1.8
-
--
—
-
Perfluorododecanoic acid (PFDoA}
-
-
< 2.5
~
<1.8
<1.8
—
-
—
-
-
Perfluorolieptanoic acid (Pf-HpA)
1.3
1.9
1.9
Perfluorohexanesulfonate (PFHxS)
3.5
3.5
4.3
-
Perfluorohexarwic acid (PFHxA)
< 2.5
-
<1.8
2.2
—
—
—
--
Perfluorononanoic acid (PFNA)
-
< 2.5
-
<1.8
<1.8
—
«
—
-
Perfluoro-octanosutfoivite (PFOS)
-
—
6.8
-
8.2
9.6
—
—
—
-
-
Perfluorooctanoic acid (PFOA)
2.0
-
3.2
3.2
—
—
-
Perfluorotetradecanoic acid (PFTA)
< 1.2
-
<1.8
<1.8
—
—
-
Perfluorotrldecanolc acid (PFTrDA)
-
< 1.2
-
<1.8
<1.8
—
--
-
-
-
Pertluoroundecanote: acid (PRJnA)
< 7.5
-
<1.8
<1.8
—
-
—
I-6D
N ethyl perfluorooctanesulfonamldoaceUc acid (NEtFOSM)
<2.8
N-methvl perfluorooctanesulfonamidoacetlc acid (NMeFOSAA)
-
< 2.8
-
—
—
Perfluorobutanesulfonate {PFBS)
~
~
1.1
--
-
—
~
—
Perfluorodecanoic acid (PFDA)
-
-
-
< 1.9
~
-
~
-
-
-
Perfluorododecanoic acid (PFDoA)
< 1.9
Perfluoroheptanoic actd (PFHpA)
-
2.1
--
—
—
—
—
-
Perf luoroh exa nesulfonate (PFHxS)
-
-
4.1
-
—
—
—
-
-
Perfluorohexartoic acid (PFHxA)
-
-
< 1.9
-
-
—
—
—
-
-
Perfluorononanoic acid (PFNA)
-
«
«
< 1.9
-
-
—
—
—
«
Perfluoro-octanesulfonate ( PFOS)
..
-
8.3
-
-
—
—
—
Perfluorooctanoic acid (PFOA)
-
3.1
—
--
—
Perfluorotetradecanoic arid (PFTA)
—
-
< 0.94
~
-
—
—
—
~
Perfluorotridccanoic acid (PFTrDA)
--
< 0.94
-
-
—
-
-
--
Perfluoroundecanoic acid (PFUnA)
< 1.9
I-6S
N-ethyl perfluo rooctan esulfanamidoacetic acid (NEtFOSAA)
< 2.8
-
--
—
—
< 2.8
—
< 2.7
< 2.8
N-methyl peifluorooctanesulfonaiTMdoacetic acid (NMeFOSAA)
»
< 2.8
-
—
-
—
< 1.9
—
< 1.8
< 1.8
PerfluorobuUinesulfoiidte (PFBS)
<0.94
< 1.9
< 1.8
< 1.8
Perfluorodecanoic acid (PFDA)
< 1.9
-
-
-
—
< 1.9
-
< 1.8
< 1.8
Perfluorododecanoic acid (PFDoA)
< 1.9
-
-
-
—
< 1.9
-
< 1.8
< 1.8
Perfluoroheptanoic add (PFMpA)
~
~
<0.94
-
-
-
—
< 1.9
-
< 1.8
< 1.8
Perf luorohexa nesulfonate (PFHxS)
-
< 1.9
-
—
-
—
< 1.9
—
< 1.8
< 1.8
Perfluorohexanoic acid (PFHxA)
«
< 1.9
-
-
-
—
< 1.9
—
< 1.8
< 1.8
Perfluorononanoic acid (PFNA)
< 1.9
< 1.9
< 1.8
< 1.8
Perf luoro-o ctanes i ilfo rate (Pros)
-
-
< 1.9
-
—
—
< 1.9
—
< 1.8
< 1.8
Perfluorooctanoic acid (PFOA)
<0.94
-
-
-
—
< 1.9
—
< 1.8
< 1.8
Perfluorotetradecanoic acid^PFI A)
-
-
<0.94
-
--
—
—
<. 1.9
-
< 1.8
< 1.8
Perfluorotrldecanolc acid (PFTrDA)
<0.94
< 1.9
< 1.8
< 1.8
Perfluoroundecanoic acid (PFUnA)
< 1.9
-
-
-
-
< 1.9
-
< 1.8
< 1.8
Page 5 of 7
55
-------
Table 6
SUMMARY OF PFAS SAMPLING RESULTS (2018-2022)
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
Sampling Event
•1/2/2018
1/2B/2018
2018-10
2019-01
2019-09
2019-09
2019-10
2020-09
2021-O'l
2021-09
2022-10
Result Unit
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
nq/L
I-SD
N-cthyl pcrtluorooctanesulfonamidoacctic acid (NEtFOSAA)
-
-
-
—
< 2.8/<2.8
< 2.8
< 2.8
N-methyl perfluorooctanesLilforwrrtidoacetic acid (NMeFOSAA)
—
-
-
-
-
-
< 1.9/<1. a
< 1.9
< 1.9
Perfluorobutanesulfonate {PFDS)
< 1.9/<1.8
< 1.9
< 1.9
Perfluorodecanoic arid (PFDA)
-
-
-
-
-
< 1.9/<1.8
< 1.9
< 1.9
Perfluorododecanoic acid (PFDoA)
-
--
-
--
-
~
< 1.9/ <1.8
< 1.9
< 1,9
Perfluorolieptanuic ackl (PFHpA)
< 1.9/<1.8
< 1.9
< 1,9
Perfluorohexanesulfonate (PFHxS)
3.8/3.7
4.1
3.0
Perfluorohexanoic acid (PFHxA)
—
-
~
--
-
-
-
< 1.9/<1.8
< 1.9
2.3
Perfluorononanoic acid (PFNA)
--
-
-
--
--
-
..
< 1.9/<1.8
< 1.9
< 1.9
Perfluoro-octancsulfonato (PFOSJ
—
-
-
-
—
8.4/8.1
8.8
8.7
Perfiuorooctanaic acid (PFOA)
~
~
-
~
-
~
2.6/2.8
3.0
2.7
Peifluorotetradecanoic acid (PFTA)
—
-
-
-
-
-
--
< 1.9/<1.8
< 1.9
< 1.9
Perfluorotrldecanok: acid (PrTrOA)
-
-
-
—
< 1.9/ <1.8
< 1.9
< 1.9
Perfluoroundecanoic acid (PRJnA)
»
--
-
~
--
-
--
< 1.9/<1.8
< 1.9
< 1.9
II-3D
N ethyl perfluorooctanesutfonar nldoacettc acid (NEtFOSAA)
<2.8
N-methyl perfliiorooctanesiilforiamidoacetli: acid (NMeFOSAA)
-
-
< 2.8
--
-
-
--
--
-
Perfluorohutanesulfonate (PFBS)
—
-
< 0.9?
-
—
-
-
-
-
Perfluorodecanoic acid (PFDA)
< 1.8
—
-
Perfluorododecanoic acid (PFDoA)
< 1.8
Perfluoroheptanoic acid (PFHpA)
—
—
1.3
—
—
—
—
-
-
Perfluorohexartesulfonate (PFHxS)
--
~
< 1,8
-
-
-
-
-
-
Perfluorohexanoic acid (PFHxA)
-
-
< 1.8
-
-
—
-
_
-
-
Perfluorononanoic acid (PFNAJ
—
-
< 1.8
-
—
-
-
-
-
Perfluoro-octanesultonate (PFOSJ
-
-
< 1.8
-
-
-
-
-
-
Perfluorooctanolc acid (Pf"OA)
2.3
Perfluorotetradecanoic arid (PFTA)
-
-
< 0.92
—
-
—
-
Perfluorotridecanoic acid (PFTrDA]
-
-
<0.92
-
»
-
--
—
«
-
Perfluoroundecanoic acid (PFUnA)
< 1.8
II-3S
N-ethyl perfluorooctanesulfanamidoacetic acid (NEtFOSAA)
< 2.7
--
-
-
~
--
-
--
-
»
-
N-methyl perfluorooctanesulforHiT*doacetic acid (NMeFOSAA)
< 2.7
--
~
-
~
—
«
—
-
-
PerfluorobuUinesulfoiidle (PFBS)
< 0.91
Perfluorodecanoic acid (PFDA)
< 1.8
-
-
-
-
-
--
-
-
Perfluorododecanoic acid (PFDoA)
< 0.91
--
-
-
~
—
-
-
-
-
Perfiuoroheptanoic acid (PHlpA)
5.5
-
—
—
-
-
-
-
Perfluorohexanesulfonate (PFHxS)
< 1.8
»
~
--
~
-
-
-
PerfluorohexaiKiic acid (PFHxA)
3.9
-
-
-
-
--
—
-
—
--
Perfluorononanoic acid (PFNA)
3.3
Perf luoro-octanes i ilfo iiate (Pros)
3.1
~
-
-
-
-
-
—
-
-
Perfluorooctanoic ac:irt (PR">A)
14
-
-
-
—
~
-
-
--
Perfluorotetradecanoic acid (PFIA)
< 0.91
—
—
Perfluorotrldecanoic acid (PFTrDA)
<0.91
Perfluoroundecanoic acid (PFUnA)
< 1.8
~
-
-
-
--
—
—
-
-
-
Page 6 of 7
56
-------
Notes:
All cells with two values represent data with field duplicate results - parent sample/field duplicate
Not sampled = -
Not detected above reporting limit (RL) = < RL (e.g. < 1.8)
bgs = below ground surface
bTOC = below Top of Well Casing
J = estimated concentration based upon QC data
UJ = non-detect; reporting limit is imprecise
~Bedrock Borehole wells were sampled via hydrasieeve in fall 2018, redeveloped and sampled via packer sampling in discrete zones
during 2019, and then sampled via low flow at one depth thereafter.
Low flow depths bTOC determined based on dominant fracture zone for I-2B and highest concentration for I-6B. The fracture at 97*
bTOC in I-6B Is by far the dominant one as shown in concentrations via low flow.
57
-------
Table 7
Number of Wells Impacted by Indicator
Compounds and Number Greater than MCLs
1989-2022
Year
Number of Wells
Indicator compounds detected
Indicator compounds > MCL
PCE
TCE
VC
PCE
TCE
VC
1989
13
14
7
3
7
6
1990
9
16
7
4
9
3
1991
8
16
5
5
3
4
1992
8
17
7
4
4
3
1993
8
14
6
3
3
4
1994
8
15
5
3
4
3
1998
5
7
4
3
2
3
1999
6
5
5
2
3
4
2000
4
4
3
2
0
2
2001
4
5
3
2
3
2
2002
3
3
2
2
1
1
2003
5
4
1
2
1
1
2004
3
4
1
2
0
1
2005
5
4
2
2
1
1
2006
8
6
4
2
2
4
2007
3
5
5
2
1
1
2008
3
5
4
1
2
2
2009
3
3
2
1
0
1
2010
3
4
3
2
0
0
2011
2
3
2
1
0
1
2012
3
4
2
1
1
1
2013
3
4
2
2
1
2
2014
2
1
2
0
0
0
2015
3
3
2
0
0
0
2016
5
8
4
2
0
3
2017
5
8
6
2
2
0
2018 (spring)
3
2
1
0
0
0
2018 (fall)
2
1
0
0
0
0
2019
2
1
1
2
1
1
2020
2
NA
1
1
NA
1
2021
2
NA
0
0
NA
0
2022
2
NA
1
1
NA
1
Notes: 1. Data for 1989 through 1994 from Olin, 1995 letter report; number of wells = 27.
2. Data for 1995 through 1997 unavailable
3. Data for 1998 through 2017 from historic and new data as summarized In
annual reports; e.g., AMEC, 2011, maximum number of wells = 41.
4. Data for 2018 include the spring 2018 sampling round only, number of wells = 14.
5. Data for fall 2018 through 2022, number of wells = 2. Wells are only analyzed
for one or two selected VOCs that have not yet demonstrated compliance.
Starting in 2020, no wells are analyzed for TCE, therefore, it is"NA."
2018-2022 summary:
Prepared by: JPK 2/6/2023
Checked by: CF 2/9/2023
58
-------
Figure 8
SPRING 2018 VOCs/l,4-DIOXANE
FINAL RESULTS SUMMARY
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
SDG
WSG06
WSG06
WSG06
WSG06
WSG06
WSG06
WSG06
WSG06
Location
C-4D
C-4M
C-4S
C-4S
C-5D
C-5D
C-5M
C-5S
Sample Date
02 Apr 20 IS
02 Apr 20 IS
02 Apr 20 IS
02 Apr 201S
02 Apr 20IS
02 Apr 20 IS
02 Apr 2018
02 Apr 2018
Sample ID
C-4D PDB
C-4M PDB
C-4S Dup PDB
C-4S PDB
C-5D PDB
C-66DA
C-5M PDB
C-5S PDB
QC Code
FS
FS
FD
FS
FS
FD
FS
FS
Method Units Fraction Parameter Name
Result Qual.
Result Qual.
Result Qual.
Result Qual.
Result Qual.
Result Qual.
Result Qual,
Result Qual.
SWS260B ug/l T 1,1,1-Trichloroethane
0.5 U
0.5 U
20
20
0.5 U
0.5 U
0.5 U
0.7
SW8260B ug/l T 1,1,2,2-Tetrachloroethane
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
0.5 U
0.5 U
0.5 U
SWS260B ug/l T 1,1,2-Trichloroethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,1-Dichloroethane
0.5 U
0.5 U
12
12
0,5 U
0.5 U
0.2 3
0.1 3
SWS260B ug/l T ljl-Dichbroethene
0.5 U
0.5 U
0.2 3
0.2 J
0.5 U
0.5 U
0.5 U
0.5 U
SWS260B ug/l T 1,2-Dichbrobenzene
0.5 U
0.5 U
0.5 U
0,5 U
0,5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,2-Dbhbroethane
0.5 U
0,5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,2-Dfchbroprapane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,3-Dichbrobenzene
0.5 U
0.5 U
0.5 U
0,5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,4-Dichbrobenzene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 2-Chloroethyl vinyl ether
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Benzene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW826QB ug/l T Bromodichbromethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Bromoform
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Bromome thane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Carbon tetrachloride
0.5 U
0.5 U
0.5 U
0,5 U
0.5 U
0.5 U
0.5 U
0.5 U
SWS260B ug/l T Chlorobenzene
0.5 U
0.5 U
0.5 U
0,5 U
0,5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Chloroethane
0.5 U
0.5 U
0.5 3
0.5 3
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Chloroform
0.5 U
0.5 U
0.4 3
0.4 3
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Chloro methane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T cis-l,2-Dichloroethene
0.5 U
0.5 U
3.6
3.6
0,5 U
0.5 U
0.3 3
0.5 U
SW8260B ug/l T cis-l,3-Dichloroprc>pene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Dibromochloromethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Ethylbenzene
0.5 U
0.5 U
0.3 3
0.3 3
0.5 U
0.5 U
0.5 U
0.5 U
SW826QB ug/l T Methylene chloride
0.5 U
0.5 U
0.2 J
0.2 3
0.5 U
0.5 U
0.5 U
0.5 U
SWB260B ug/l T Tetrachloroethene (PCE)
0.5 U
0.5 U
1.5
1.4
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Toluene
0.5 U
0.5 U
0,5 3
0,5 3
0,5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T trans-l.,2-Dichloroethene
0.5 U
0.5 U
0.1 3
0.1 3
0,5 U
0.5 U
0.5 U
0.5 U
SWS260B ug/l T trans-l,3-Dichloropropene
0.5 U
0.5 U
0.5 U
0,5 U
0,5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Tricbloroethene (TCE)
0.5 U
0.5 U
1
1.1
0,5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Trichlorofluoromethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Vinyl Chloride
0.5 U
0.5 U
0.1 3
0.1 3
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Xylene, (o)
0.5 U
0.5 U
4.8
4.6
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Xylenes (m,p)
0.5 U
0.5 U
3.4
3.3
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Xylenes, Total
0.5 U
0.5 U
8.2
7.9
0.5 U
0.5 U
0.5 U
0.5 U
522 ua/l T 1,4-Dbxane
NOTES:
ug/l - micrograms per liter
U = not detected at reported quantitation limit
J = estimated value T = total
FS = field sample FD = field duplicate
PDB = passive diffusion bag sample
F^ge 1 of 2
59
-------
Figure 8
SPRING 2018 VOCs/l,4-DIOXANE
FINAL RESULTS SUMMARY
WESTERN SAND AND GRAVEL SUPERFUND SITE
BURRILLVILLE, RHODE ISLAND
SDG
WSG06
WSG06
WSG06
WSG06
WSG06
WSG06
1927661 413047
1927661 413047
Location
C-6D
C-6M
C-6S
II-3D
II-3M
II-3S
C-4D
C-5D
Sample Date
02 Apr 2018
02 Apr 20 IS
02 Apr 2018
02 Apr 2018
02 Apr 2018
02 Apr 2018
03 Apr 2018
02 Apr 2018
Sample ID
C-6D PDB
C-6M PDB
C-6S PDB
II-3D PDB
II-3M PDB
II-3S PDB
C-4D
C-5D
QC Code
FS
FS
FS
FS
FS
FS
FS
FS
Method Units Fraction Parameter Name
Result Qual.
Result Qual.
Result Qual.
Result Qual,
Result Qual.
Result Qual.
Result Qual.
Result Qual.
SW8260B ug/l T 1,1,1-Trichloroethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
1.8
SW8260B ug/l T 1,1,2,2-Tetrachloroethane
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
0.5 U
SWS260B ug/l T 1,1,2-Trichloroethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,1-Dichbroethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
2.5
SW8260B ug/l T 1,1- D k: h b ro e t( >e re
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.1 J
S W8260 B ug/l T 1,2-Dichbrobenzene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,2-Dichta methane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,2-Dichbro propane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,3-Dichtarobenzene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 1,4-Dichbrobenzene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T 2-Chloroethyl vinyl ether
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
SW8260B ug/l T Benzene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Bromodichloro methane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Bromofoirn
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
SW8260B ug/l T Bromomethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Carbon tetrachloride
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
SW8260B ug/l T Chlorobenzene
0,5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Chloroethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Chloroform
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
SW8260B ug/l T Chlororrfethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T cis-l,2-Dichloroethene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
5,3
SW8260B ug/l T ris-l,3-Dichloropropene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Dibromochbromethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Ethyl benzene
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
0.5 U
SWB260B ug/l T Methylene chloride
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Tetrachloroethene (PCE)
0.5 U
0.1 J
0.5 U
0.5 U
0.5 U
0.4 J
SWS260B ug/l T Toluene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T trans-l,2-Dichloroethene
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T trans-1,3-Dichloroprapene
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
0,5 U
SW8260B ug/l T Trichloroethene (TCE)
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.1 J
SW8260B ug/l T Trichbrofluoromethane
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Vinyl Chloride
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Xylene, (o)
0.5 U
0.5 U
0.5 U
0.5 U
0,5 U
0.5 U
SW8260B ug/l T Xylenes (m,p)
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
SW8260B ug/l T Xylenes, Total
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
0.5 U
522 ug/l T 1,4-Dbxane
4.9
0.07 U
NOTES:
ug/l ~ micrograms per liter
U = not detected at reported quantitation limit
J = estimated value T - total
FS - field sample FD — field duplicate
PDB = passive diffusion bag sample
F&ge 2 of 2
60
-------
Oreumrf 3alR V.'iVF'i bs',Pr=jsr.l!Ar.d WnknliaM '^aln'jj^jnrJr.'-Slff'Prcoc-s'jfJl -i tioid .-Td (•-•-vnt'i'r'a.inoRi.mrM'Anrdnnr.v-ravRl 14 F;i-xnrc L;ho-ih.-» r»ms.Tx:l
61
-------
Docurrem Pslh: R'aMWa-efeld Dal3prcpctg'GIS'J3rojectsfiQliri-Sand afld Gravel Uapd&:urrents''Sa"aandGrawl PFAS Cbenbox.trttd
Location
Date
Result
ln*m
4/2/2019
75
C-6S
10/14/2019
73
9/22/2020
20.8
9/29/2021
35
C-6M
10/1/2019
<3.8
C-6D
4/2/2019
<3.1
Location
Date
Result
In«/L|
II-3S
4/2/2018
17.1
II 3D
4/2/2019
<4.1
Location
Date
Result
/T
10/2/2019
<3.4
(
I-3S
9/23/2020
<3.8
/
9/28/2021
<4.2
1 I
I \
II-3SMD -$?C-5SMD
Location
Date
Result
C-1D
10/17/2018
<2.83
Location
Date
Result
e*/L)
C-4S
4/2/2018
296.9
4/24/2018
630
10/17/2018
197.3
4/1/2019
217,2
10/1/2019
<6.1
9/22/2020
<3.8
9/29/2021
114.4
C4M
10/1/2019
7
C-4D
4/1/2019
10
"*"E -VC-3SMD
¦VC-2SMD
*E-3
»SG-3
*0W-5 ^l-8SMD
Location
Date
Result
I-6S
10/16/2018
<2.84
9/23/2020
<3.8
9/28/2021
<3.6
I-6D
4/2/2019
114
I-6B
10/17/2018
8.8
I-6B-97
9/11/2019
114
1 6B 118
9/11/2019
12-8
Location
Date
Result
l-WU
C-5S
10/1/2019
20.3
¦%I-23MDB
SfSO-1-
Location
Date
Result
I-8D
4/28/2021
16.8
9/28/2021
11-8
Location
Date
Result
Inn/L)
I-2S
10/17/2018
<7.14
9/22/2020
<6.9
9/28/2021
<7.6
1 2D
4/2/2019
10.4
I-2B
10/17/2018
9.7
I-2B 111
9/10/2019
20.1
1 2B 122
9/11/2019
13.1
-S-HSMO
Tarkiln Brook^^^r
-VII-2SMD
-£-|l-5SM>
Prepared/Date: EFG 05/19/22
Checked'Date: KMH 05/19/22
Legend
Historic Monitoring
•<51 Monitoring Well
Piezometer
% Stream Gauge
— Stream Sampling
a Town Boundary
| Parcel Boundaiy
I"*" T| Capped
*—*- Fenced
Water
Datalayer Sources: Burrillvilie Parcel Boundaries provided
by trie Town of Burrillvilie Planning Department on
cn /26/2018. Parcel boundaries for the Town of North
Smithfield approximated based on information from the
Town of North Smithfield web GIS. Town boundaries
obtained from RIGIS.
Notes:
1 .Results shown are the sum of PFOcS and PFOA.
2. USEPA Screening Level is 40.1 rvg'L.
Western Sand and Gravel
Burrillvilie, Rhode Island
wood.
PFAS in Groundwater
62
-------
Appendix D
Piezometric Contour Maps
Figure D-l: Piezometric Contours for Shallow Wells (Measured March 2022)
Figure D-2: Piezometric Contours for Medium Wells (Measured March 2022)
Figure D-3: Piezometric Contours for Medium Wells (Measured March 2022)
Figure D-4: Piezometric Contours for Shallow Wells (Measured September 2022)
Figure D-5: Piezometric Contours for Medium Wells (Measured September 2022)
Figure D-6: Piezometric Contours for Deep Wells (Measured September 2022)
63
-------
Western Sand and Gravel
Burrillville, Rhode Island
Figure D-1
Piezometric Contours for Shallow Wells
Measured March 2022
Legend
• Historic Well
A Phase I or Closure Monitoring Wells
~ Phase II Well
¦ Piezometer
* Stream Gauge
a Stream Sampling Location
_ Interpreted Potentiometric Surface,
Dasihed Where Inferred
256.16 Groundwater Elevation (Feet)
Prepared/Date: JMM 02/D8/23
Checked/Date JP 02/08/23
64
-------
Western Sand arid Gravel
Burrilfville, Rhode Island
Figure D-2
Piezometric Contours for Medium Wells
Measured March 2022
Prepared.'Date: JMM 02/08/23
Checked/Date JP 02/08/23
Legend
• Historic Well
~ Phase I or Closure Manrtoring Wells
~ Phase 11 Well
¦ Piezometer
* Stream Gauge
a Stream Sampling Location
Interpreted Potentiometric Surface;
Dashed Where Inferred
256.16 Groundwater Elevation (Feet)
65
-------
Western Sand and Gravel
Burrillville, Rhode Island
Figure D-3
Piezometric Contours for Deep Wells
Measured March 2022
Legend
•
Historic V\fell
~
Phase I or Closure Monitoring VAfel Is
J
Phase II Well
¦
Piezometer
A
Stream Gauge
A
Stream Sampling Location
Interpreted Potentiometric Surface,
Dashed Where Inferred
256.16
Groundwater Elevation (Feet)
Groundwater elevation from I-6D is not
included as the depth appears to have
been recorded in error
Prepared/Date: JMM02/13V23
Checked/Date JP 02/13/23
66
-------
Western Sand and Gravel
Burrillville, Rhode Island
\\S
Figure D-4
Piezometric Contours for Shallow Wells
Measured September 2022
Legend
• Historic Well
~ Phase I or Closure Monitoring Wells
~ Phase 11 Well
¦ Piezometer
a Stream Gauge
a Stream Sampling Location
_ Interpreted Potentiometric Surface,
Dashed Where Inferred
256.16 G ro undwate r E leva tio n (Fe et)
Preparect'Date: JMM 02/08/23
CheckedfDat© JP 02/08/23
67
-------
Western Sand arid Gravel
Burrillville, Rhode Island
\\S
Figure D-5
Piezometric Contours for Medium Wells
Measured September 2022
Legend
• Historic Well
A Phase I or Closure Mariftonng Wells
~ Phase 11 Well
¦ Piezometer
* Stream Gauge
a Stream Sampling Location
_ Interpreted Potentiometric Surface,
Dashed Where Inferred
256.16 Groundwater Elevation (Feet)
Prepared/Date: JMM 02/09/23
Checked/Date JP 02/09/23
4 MM
256.52
68
-------
Western Sand and Gravel
Burrillville, Rhode Island
\\s
Figure D-6
Piezometric Contours for Deep Wells
Measured September 2022
Legend
• Historic Well
A Phase I or Closure Monitoring Wells
~ Phase II Well
¦ Piezometer
* Stream Gauge
a Stream Sampling Location
_ Interpreted Potentiometric Surface,
Dashed Where Inferred
25616 Groundwater Elevation (Feet)
Prepared/Date: JMM 02/00/23
CheckedfDat© JP 02/08/23
69
-------
Appendix E
Tables & Figures Documenting Remedy Performance
Table E-l: Outlier Identification
Table E-2A: Mann-Kendall Regression Analysis - Tetrachloroethene
Table E-2B: Mann-Kendall Regression Analysis - Vinyl Chloride
Table E-2C: Mann Kendall Regression Analysis - Monitoring Well and Compound
Figure E-l: Wilcoxon Signed Rank Test for Tetrachloroethene
Figure E-2: Wilcoxon Signed Rank Test for Vinyl Chloride
Figure E-3: Theoretical vs Actual Attenuation for Tetrachloroethene (PCE)
Figure E-4: Theoretical vs Actual Attenuation for Vinyl Chloride (VC)
Figure E-5: PCE, TCE, and VC Concentrations in Monitoring Well C-4S versus Time
Figure E-6: PCE, TCE, and VC Concentrations in Monitoring Well I1-3S versus Time
Figure E-7: Monitoring Well C-4S Total VOC Concentration vs Time
Figure E-8: Monitoring Well 11-3S Total VOC Concentration vs Time
70
-------
Table E-1
Outlier Identification: Regression Outputs
3/2212023 8:03:07 AM
l toi ] -1|
3: T; i 1,D G 2017.MPJ'
Regression Analysis: PCE versus t
The regression equation is
PCE - 14.4 - 0.0120 t
Predictor * SE - - I P
Constant i 2, • 6.30 0.000
t -i i 11 ~ 0.C 3 < -1.00 0,319
S - 12.6973 R-Sq = 1.21 R-Sq(adj) - 0.01
PRESS - 14125,4 R-Sq(pred) - 0,001
Analysis of Variance
DF MS F P
1 162.4 1.01 0.319
83 . 161,2
II nu 3 u a 1 Observations
bs
t I
CE
Fit L
E Fit
Residual
St Resid
1
-25 64
00
-i. _
2. 53
4 9.28
3.9 6R.
55
153 49
00
12*11
. b
36.89
2.92R
64
252 70
00
11.40
5 8 * 6 0
4. 66R
74
312 40
00
10.68
i
29,32
2.35R
79
343 42
00
10.31
: . i'.!
31.69
2.55R
R denotes an observation with a large standardized residual.
Durbin-Watson statistic = 1.69234
Fitted Line: PCE versus t
Regression Analysis: in_PCE versus t
The regression equation is
In PCE_ = 2.53 - 0.00322 t
Predictor 1 £L 1 i _r T P
C on s t ant . 13. 0 6 0. 0 0 0
t -O.i 1« 0. ' 1 1 -3.18 0.002
1.07694 R Sq = 3.0.9% R-Sq(adj) = 9.81
Page 1
71
-------
Table E-1
Outlier Identification: Regression Outputs
PRESS - 102.140 R-Sq(pred) = 5.411
An alysis of Var i a nc e
I , > DF SS MS F E
1 _ _ori 1 Li. 1. 11.716 10.10 0.002
> - i- Error 83 • . . 1.160
It,] 84 ! -. "
IJ nus ua1 Obs ervat i on s
Obs
t.
ln_
JPCE
Fit
SE
Fit
i r t St Resid
13
30
0
262
.4
0
171
- . ! ~
64
252
4
24 8
1. -1
0
154
_ .1 _ _ .
74
312
3
689
i.» d j. r
0
199
7R
337
-2
303
1-450
0
220
_ . t -
79
343
3
738
1.431
0
225
2.307 z.iyK
R denotes an observation with a. large standardized residual.
D u i: b i. n - Wa t s on s t a t i s t .1. c
2. 0 05 67
Fitted Line; ln_PCE versus t
Regression Analysis; VC versus t
vc
aquation
44.4 - 0.124 t
t.
Coef SE Coef T P
4 4.446 9,920 4,48 0,000
-0.12410 0.05174 -2.40 0.019
S = 55.0637 R-Sq = 6.51 R-Sq(adj} « 5.41
PRESS = 269477 R-Sq(pred) = 0.001
Analysis of Variance
DF
1
83
84
SS
17444
251657
2691.01
F P
5.75 0.019
Unu s ua1 Observa ti ons
t
Obs
1
66
-18
265
VC
4 3 0,00
160.00
200.00
Fit
47.55
4 6.68
11.56
SE Fit
10,98
10.68
Residual
113.32
188.44
St Res id.
7, 0 9 R
2.1 OR
3.4 6R
R denotes an observation with a large standardized residual.
Page 2
72
-------
Table E-1
Outlier Identification: Regression Outputs
Durbin-Watson statistic = 0,921360
Fitted Line: VC versus t
Regression Analysis; ln_VC versus t
The regress ion equation is
In VC 2.86 - 0.00749 t
Predictor Coef S" ~ ~ T P
Constant 2,8585 9.32 0.000
t -0.0074 85 0. -4.68 0,000
S - 1.70192 R-Sq = 20.9% R-Sq(adj) - 19.91
PRESS = 254„302 R-Sq(pred) = 16.151
Analysis of Variance
DF SS MS F P
on. I 63.4 62 63,4 62 21.91 0.000
Error 83 240,411 2.897
84 303,873
ITnus ual Obs e rvat i ons
¦bs t In VC
Residual St
Res id
66 265 5 * 2*98
4.423
2 „ 63R
73 306 4.500 i .1
3.932
2.35R
81 354 3.611
3.4 02
2.05R
R denotes an observation with a large standardized residual.
Durbin-Watson statistic = 1.55341
Fitted Line; In VC versus t
Page 3
73
-------
Table E-2A
Outputs for Mann-K«nctall Test
Tadach lororthons
User Selected Options
Date/Time of Computation
From Fits
Full Precision
Confidence Coefficient
Lewel of Significance
PCE
Qanaral Statistics
Number or Reported Events Not Used 0
Number of Generated Events 85
Number Values Reported (n) 85
Minimum 0.1
Maximum 70
Mean 12.58
Geometric Mean 7.703
Median 9
Standard Dwiation 12.7
Coefficient of Variation 1.009
Mann-Kandall Tsst
M-K Test Value (S) -784
Critical Value (0.1) -1.282
Standard Deviation of S 263.4
Standardized Value of S -2.973
Approximate p-value 0.00148
Statistically significant mMmncm of a decreasing
trend st th» specified Iwsl of significance.
Mann-Kandall Trend Tast Analysis
ProUCL 5.2 3/21/2023 1:11:40 PM
ProUCUnputxIs
OFF
0,9
0.1
74
-------
Table E-2B
Outputs for Mann-Kendall Test
Vinyl Chloride
User Selected Options
Date/Time of Computation
From Fits
Full Precision
Confidence Coefficient
Lewel of Significance
VC
Garters! Statistics
Number or Reported Events Not Used 0
Number of Generated Events 85
Number Values Reported (n) 85
Minimum 0,08
Maximum 430
Mean 25.45
Geometric Mean 5.529
Median 5
Standard Dwiation 56.6
Coefficient of Variation 2.224
Mann-Kandall Tsst
M-K Test Value (S) -1254
Critical Value (0.1) -1.282
Standard Deviation of S 263.4
Standardized Value of S -4.768
Approximate p-value 9.7919E-7
Statistically significant mMmncm of a decreasing
trend st th» specified Iwsl of significance.
Msnn-Kandall Trend Ttwt Analysis
ProUCL 5.2 3/21/2023 1:11:54 PM
ProUCUnputxIs
OFF
0,9
0.1
75
-------
Table E-2C
Output for Mann-Kendall Test
By Well and Chemical
Marwv-Kanctall Trawl Test Analysis
User Selected Options
Date/Time of Computation ProUCL 5.2 3/22/2023 9:26:06 AM
From File ProUCL input by well.xls
Full Precision OFF
Confidence Coefficient 0.9
Level of Significance 0.1
R®sult-c*4s_pce
General Statistics
Number of Events Reported (m) 16
Number of Missing Events 0
Number or Reported Events Used 10
Number Values Reported (n) 10
Minimum 0.1
Maximum 42
Mean 9,388
Geometric Mean 2.978
Median 2.95
Standard Deviation 13.08
Coefficient of Variation 1.398
Mann-Kenddl Test
M-K Test Value (S) 4
Tabulated p-value 0,364
Standard Deviation of S 11.14
Standardized Value of S 0.269
Approximate p-value 0.394
Imuffldort nvklonoo to ktandfjr a significant
u6na 81 Hi® Sp6Clit0Q 18Vol OT SiQnlTwwICv.
76
-------
Table E-2C
Output for Mann-Kendall Test
By Well and Chemical
Result-U-3s_po8
General Statistics
Number of Events Reported (m) 10
Number of Missing Events 0
Number or Reported Events Used 10
Number Values Reported (n) 10
Minimum 0.375
Maximum 24.5
Mean 3,572
Geometric Mean 1.26
Median 1.075
Standard Deviation 7.416
Coefficient of Variation 2.076
Mann-Kendall Test
M-K Test Value (S) 2
Tabulated p-value 0.431
Standard Deviation of S 11.14
Standardized Value of S 0.0898
Approximate p-value 0.464
iriauniwiaiit irViuwwe u3 KJanuty a aiyrtiticmu
77
-------
Table E-2C
Output for Mann-Kendall Test
By Well and Chemical
Rosult-l-3s_vc
General Statistics
Number of Events Reported (m) 10
Number of Missing Events 0
Number or Reported Events Used 10
Number Values Reported (n) 10
Minimum 0.08
Maximum 37
Mean 10,78
Geometric Mean 1.641
Median 0.5
Standard Deviation 15.46
Coefficient of Variation 1.435
Mann-Kendall Test
M-K Test Value {S) 13
Tabulated p-value 0.148
Standard Deviation of S 10.79
Standardized Value of S 1.113
Approximate p-value 0.133
Insufficient wldence to Identify a significant
trend at the specified level of significant*.
78
-------
Figure E-1
Wilcoxon Signed Rank Test for Tetrachloroethene
One Sampto Wilcoxon Signed Bunk Ta«t (or UncensorwJ Full Data Sets without NDs
User Selected Options
Date/Time of Computation ProllCL 5.2 3/22/202310:37:40 AM
From File ProUCLlnputWilcoxon.xls
Full Precision OFF
Confidence Coefficient 95%
Substantial Difference 0.000
Action Level 0.000
Selected Null Hypothesis Mean/Median = Action/compliance Limit (2 Sided Alternative)
Alternative Hypothesis Mean/Median <> Action/compliance Limit
FCE diff (actual mux - theoretical max)
One Sampl® Wilcoxon Signed Rank Test
Raw Statistics
Number of Valid Observations 85
Number of Distinct Observations 85
Minimum -44.86
Maximum 57.93
Mean -14.48
Median -16.05
SD 18.71
SE of Mean 2.03
Number Abwe Action Level 13
Number Equal Action Level 1
Number Below Action Level 71
T-plus 440
T-minus 3130
HO: Sample MwmMacfiin = 0
Large Sample z-Tast Statistic 6.188
Lower Critical Value (0.025) -1.96
Upper Critical Value (0.975) 1.96
P-Value 6.182E-10
Conclusion with Alpha = 0.05
Rojwet HO, Conclude Mwn/Macftan <» 0
P-Vslu»« Alpha {0.05)
79
-------
Figure E-2
Wllcoxon Signed Rank Test for Vinyl Chloride
Ona Sampta Wlcxxon Signod Rank Twt far Uneensored Full Data Sate without NDs
User Selected Options
Date/Time of Computation
From File
Full Precision
Confidence Coefficient
Substantial Difference
Action Level
Selected Null Hypothesis
Alternative Hypothesis
VC cliff (Kauai max - theoretical mmx)
OraSamptaWitcoscori Signed Rank Tost
Raw Statistics
Number of Valid Observations
Number of Distinct Observations
Minimum
Maximum
Mean
Median
SD
SE of Mean
Number Above Action Level
Number Equal Action L0/0I
Number Below Action Lwel
T-pIus
T-mirtus
HO: Sample MwnAMan = 0
Large Sample z-Test Statistic
Lower Critical Value (0.025)
Upper Critical Value (0,975)
P-Value
Conclusion with Alpha = 0.05
Rojwet HO, Conclude Mwn/Madtan <» 0
P-Vslu»« Alpha {0.05)
80
ProUCL 5.2 3/22/2023 10:38:57 AM
ProUCL Input Wtle0x0n.xls
OFF
95%
0.000
0.000
Mean/Median = Action/compliance Limit (2 Sided Alternative)
Mean/Median <> Action/compliance Limit
85
76
-187.4
198
-12.29
-1.5
52.76
5.723
28
1
56
1289
2281
2.339
-1.96
1.96
0.0164
-------
Figure E-3. Theoretical Attenuation vs Actual Concentrations
Tetrachloroethene (PCE)
75.0
70.0
65.0
60.0
55.0
50.0
.£
CL
&
45.0
£
_o
40.0
1
35.0
juj
£
30.0
a
*
W
o
25.0
20.0
15.0
10.0
5.0
0.0
-Theoretical Concentration
Actual Maximum Concentration
Target Concentration - 5.0 ppb
£T 50 50 5ST 50 50 50 3CTjo 3CT XT 30'
Sampling Date
outlier
Vwfd-fs1\ProiecteSold_Wakefield_Data\projeds\6107230018 Olin Western S&G Landfill 2023\8.0 Proj Deliverables^. 1 ReportsSFYR Support\Statistical analysisS
Flgures_2023Rlgure E-3 PCE 2023 Page 1 Of 1
81
-------
Figure E-4. Theoretical Attenuation vs Actual Concentrations
Vinyl Chloride (VC)
Sampling Date Q outlier
Vwfd-fs 1 \ProJects\o Id_Wakefi©Id_Data\projecis\6107230018 Olin Western S&G LandfiSI 2023V8.0 Proj Deliverables^. 1 ReportsSFYR SupportVStatistical analysisN
Figures_2023Figure E-4 VC 2023 P39e 1 °f 1
82
-------
Figure E-5: PCE, TCE, and VC Concentrations in Monitoring Well C-4S versus Time
PCE —•—TCE —•—VC Linear (PCE) Linear (TCE) Linear (VC)
83
-------
Figure E-6: PCE, TCE, and VC Concentrations in Monitoring Well II-3S versus Time
45
4/1/2013
5/10/20lfamP'e Dat<%/22/2018 2/4/2020
VC Linear (PCE) Linear (TCE)
6/18/2021
¦ Linear (VC)
10/31/2022
84
-------
10000
1000
(
nr
"5s
| 100
+J
ro
4->
c
(D
O
c
o
u
u
o
>
S 10
o
1—
tLO
o
1
1
0.1
Mar
Figure E-7: Monitoring Well C-4S Total VOC Concentration vs Time
•
•
•
•
•
•
•
•
•
•
•
»
•
•
•
•
•
•
•
•
•
•
•
'"'if
•
• •
2007 Aug
2008 Dec
2009 May
2011 Sep
2012 Jan
2014 Jun
Sample D
2015 Oct
ate
2016 Mar
2018 Jul 2
019 Dec
2020 Apr
2022
85
-------
10000
1000
1
3
ao
3
1 100
+J
ro
4->
c
(D
O
c
o
u
u
o
>
2 10
o
1—
tLO
o
1
1
0.1
Mar
Figure E-8: Monitoring Well II-3S Total VOC Concentration vs Time
»
9 •
••
•
•
•
•
•
•
• •
•
i
•
•
•
•
1
•
•
•
•
•
•
•
•
•
2007 Aug
2008 Dec
2009 May
2011 Sep
2012 Jan
2014 Jun:
Sample D
2015 Oct
ate
2016 Mar
2018 Jul 2
019 Dec
2020 Apr
2022
86
-------
Appendix F
Eco-Assessment for Western Sand & Gravel Five-Year Review
87
-------
Eco-Assessment for Western Sand & Gravel Five-Year Review
The surface water and sediment assessment activities and the substantial improvements
in groundwater quality at the Site over the past three decades indicate there are minimal,
if any, impacts to surface water and sediment, and that risks to environmental and human
receptors from potential exposures to surface water and sediment in Tarkiln Brook are de
minimis.
This text summarizes the environmental assessment activities that have been conducted at the
Western Sand & Gravel Superfund site in Burrillville, R1 in response to the March 1991 Rhode
Island Department of Environmental Management (RI DEM) request for additional investigation
of surface water and sediment.
The remedial investigation (Rl) for the site (dated June 1990) concluded that 1) there were no
signs of ecological stress at any location and 2) concentrations in surface water and sediment
represented a negligible potential for adverse effects to either humans or the environment.
However, in a March 5, 1991 letter, RI DEM requested additional investigation to address the
agency's concerns about potential in-stream effects (impacts on downstream recreational uses
of surface water and potential impacts on macroinvertebrate communities and fish in Tarkiln
Brook and the Slatersville Reservoir). The March 1991 RI DEM request for additional
investigation included, as an attachment, a proposed scope of work. Subsequently, Olin
representatives and consultants met with RI DEM representatives on June 13, 1991. Following
that meeting, a July 23,1991 letter from Olin to RI DEM indicated that Olin agreed to conduct
surface water bioassays and surface water chemical sampling and analysis, sediment sampling
and chemical field screening analysis, and artificial substrate macroinvertebrate sampling.
These activities were completed in 1991 and 1992 and the results were submitted to USEPA
and RI DEM on March 16,1992 (surface water and sediment sampling and analysis and artificial
substrate macroinvertebrate sampling; BCM, 1992a), August 27, 1992 (surface water bioassays
and surface water sampling and analysis; BCM, 1992b), and August 18, 1993 (surface water
bioassays; BCM, 1993a). Sampling and field screening of sediment was conducted in June
1992 (BCM, 1993b). In the July 23; 1991 letter, Olin stated that the surface water and sediment
data collected to that point in time indicated that sampling and chemical analysis of
macroinvertebrate and fish tissue was not necessary.
Based on the Conceptual Site Model, any Site-related impacts to surface water and sediment
would be associated with potential discharge of groundwater to Tarkiln Brook, and potentially to
downstream water bodies Chlorinated volatile organic compounds (VOCs) are the primary Site
groundwater contaminants. Although there are several metals listed as COCs in the ROD, those metals
are listed because, at the time of the ROD, all chemicals thatwere evaluated in the risk assessment in the
Rl (i.e., all chemicals detected in groundwater)
were included on the COC list (whether or not they posed any significant risk, whether or not
they were determined to be Site-related contaminants, or even if they were likely natural
background constituents). The Rl concluded that: the VOCs detected in SW were site-related
(except for lab contaminants), VOCs had not really impacted sediments, semi-volatile organic
compounds (SVOCs) were indicative of off-site sources (e.g., roofing tar, road building), and
metals were consistent with background.
Further, the surface water and sediment samples collected from the mouth of Slatersville
Reservoir in September 1988 during the Rl (STR-5 and SED-5) contained no site-related,
contamination, the groundwater plume currently does not extend to the reservoir (see Figure 8
from the 2017 Annual Report), and the frequency of detection and concentrations of VOCs in
groundwater that potentially discharge to Tarkiln Brook have decreased substantially since the
88
-------
R1 investigations conducted prior to 1991 as documented in numerous monitored natural
attenuation status reports. Therefore, additional sampling of the Slatersville Reservoir was not
considered necessary and was not performed as part of the post-RI assessment activities.
Below is a summary of the activities conducted in 1991 and 1992 as well as a discussion of the
results of those activities. Attachment 1 is a copy of Figure 2.1 from the R1 Report that shows
surface water and sediment sampling locations, annotated to include the locations from the
1991 -1992 sampling activities.
August 1991: Artificial substrate sampling and sediment and surface water sampling
Artificial substrates were deployed in Tarkiln Brook on August 23, 1991 and collected on October
7, 1991. Samplers were placed in Five locations: STR-1 and STR-2-1 upstream, STR-3 adjacent
to the site, STR-SUPL in the diverted channel of the brook, and STR-4-1 downstream. These
locations are consistent with the sampling locations requested in the March 1991 letter. A
R1 DEM staff member was present during the deployment of the samplers. It should also be
noted that the samplers were deployed three days after the passage of Hurricane Bob.
The samplers at location STR-3 were removed, apparently by vandals, and were not recovered.
Based on the remaining data, two hypotheses were tested: the "contamination" hypothesis,
which was that the site is the driver for the pattern of species richness/diversity and number of
individuals, and the "distance" hypothesis, which was that the patterns reflect only the distance
from the source of colonizers and are not indicative of contamination.
The results of the analyses did not clearly support one hypothesis over the other - some factors
supported the contamination hypothesis, some supported the distance hypothesis, and some
supported both hypotheses. The analyses were limited by the lack of data from STR-3, as it was
challenging to identify gradients in the results using solely upstream and downstream sampling
locations without the ability to compare to a sample adjacent to the site.
Surface water and sediment samples were collected at STR-l/SED-1, STR-4-1/SED-4-1, and
STR-SUPL/SED-SUPL in September 1991 (consistent with the proposed sampling plan). The
chemical data for sediment samples indicated that detections of semi-volatile organic chemicals
(SVOCs) and metals were likely due to off-site non-point sources and natural background
concentrations (metals only). The data indicated that the low flow divergent branch of Tarkiln
Brook near the site (STR-SUPL/SED-SUPL) was the most probable point of maximum site
impact to the surface water and sediments. Regardless, concentrations of chemicals detected in
surface water and at SED-SUPL were lower than in 1988-1989, likely due to either a lower ratio
of discharging groundwater to stream flow, the natural attenuation of chemical concentrations in
groundwater at the site, or contaminant source control on the site (e.g., the installation of the
impermeable landfill cap at the site in 1987).
01 in communicated these results to R1 DEM and USEPA on March 16, 1992, and stated, in
conclusion, that "should contamination actually be affecting the biological community in the
Brook or distributary branch, 01 in believes these effects will be mitigated with time and will
parallel the improvements in groundwater quality which have been observed to occur with time.
[Olin] remain[ed] concerned that the hydraulic characteristics and natural substrate
characteristics of the low flow divergent branch [i.e., STR-SUPL] may influence the biological
community structure at that location." In the 26 years since these activities were conducted, the
concentrations of VOCs in groundwater have continued to decrease at the site, and, with some
exceptions, are below their Interim Cleanup Levels (ICLs) (see the Annual Reports for graphs
showing the decline in the concentrations of key VOCs at the site).
89
-------
June 1992: Surface water sampling for bioassay testing
Subsequent to a meeting with RI DEM in April 1992, in a letter dated May 6, 1992 and work plan
dated June 3, 1992, 01 in proposed additional assessment of Tarkiln Brook consisting of
bioassay tests using surface water samples from locations adjacent to (STR-SUPL), upstream of
(STR-1), and downstream of (SG-2A) the site and macroinvertebrate Ceriodaphnia duhia as the
test subject. Chronic and acute bioassays were conducted based on a recommendation from
RI DEM. The sampling locations arid type of test for each location were selected by RI DEM,
and sampling procedures were discussed with and approved by RI DEM prior to sampling.
Stream flow measurements were also taken to estimate the rate of groundwater discharge to
surface water. Chemical analyses of two of the surface water samples were also conducted, as
requested by RI DEM.
Due to mass mortality of the control subjects in the two iterations of the chronic toxicity tests,
chronic toxicity results could not be determined for this sampling event. The chronic bioassays
were terminated with the approval of RI DEM. However, the results were sufficient to evaluate
acute toxicity (48-hour exposure duration). Bioassay tests done using 100 percent stream water
did not result in lethality to 50 percent of the test population; therefore, the LC50s
(concentrations lethal to 50 percent of the population) were greater than 100 percent for all
sampling locations and both test iterations.
The results of the surface water chemical analyses were similar to previous results (magnitude
of, and chemicals detected). The streamflow measurements indicated that Tarkiln Brook was a losing
stream from STR-1 to STR-3 and then was a slightly gaining stream from STR-3 to STR-4. Further, the
flow rates indicated a dilution factor of approximately 20-60 from the distribution channel (i .e., where
STR-SUPL is located) to the main channel of the brook.
The May 6, 1992 letter also discussed the possibility of fish tissue analysis; 01 in specifically
stated that they proposed not to conduct this analysis at that time, and that "Olin continues to
believe that, based on the surface water and sediment analyses to date, fish tissue analyses are
not necessary." US EPA noted in its response to comments on the 1991 Record of Decision
(ROD) that fish tissue analyses are typically not required unless the levels of contaminants in
surface water and sediments are significantly higher than those that have been detected at the
Western Sand & Gravel site. Therefore, collection and analysis offish tissue was not, and has
not, been conducted at the site to date.
June 1992: Sediment field screening
Field screening of sediment was conducted in June 1992 at the request of RI DEM. Sediment
samples were collected every 25 ft downstream of SG-2A up to 125 ft (Five locations total, at
locations designated by RI DEM), and then headspace screening of the samples was conducted.
Benzene and vinyl chloride were detected in each sample, but in each case, except one, the
concentrations could not be quantified because they were below the reporting limit of 10 ppbv.
Vinyl chloride was detected at an estimated concentration of 14 ppbv in sample 2 SED. It
should be noted that vinyl chloride was also detected in the majority of column, syringe and
equipment blank samples collected. Trichloroethylene and tetrachloroethylene were not detected
except for a concentration of TCE below the reporting limit in 2 SED.
September 1992: Surface water sampling for bioassay testing
Bioassay tests were then repeated in September 1992 with the same approach as the June
90
-------
1992 tests to attempt to obtain chronic toxicity testing results.
A 48-hour exposure period was used for sampling location STR-SUPL, and a 7-day exposure
period was used for sampling locations STR-1 and SG-2A. For short-term exposures
(48-hours), the LC50s for the three locations were greater than 100 percent, consistent with the
June 1992 results.
For long-term/chronic toxicity, the Lowest Observed Effects Concentrations (LOECs) for both
STR-1 and SG-2 A were greater than 100 percent of the test water and the No Observed Effects
Concentrations (NOECs) were 100 percent test water, meaning that no long-term toxic effects of
exposure to surface water from Tarkiln Brook were observed.
Reproductive toxicity was also evaluated in the chronic bioassays. The NOEC and LOEC for
STR-1 (the upgradient location) were 100 percent and greater than 100 percent, respectively,
indicating no effects on reproduction in comparison to the associated control group. For location
SG-2 A, there was a statistically significant decrease in the number of young produced by
organisms in the 100 percent test water group relative to its control group. Based on this result,
the NOEC and LOEC for reproduction for SG-2A were greater than 50 percent and 100 percent,
respectively. However, when the number of young for sample location SG-2A was compared
directly to the number of young for location STR-1 (the background condition), there was no
difference. Based on this comparison, it was concluded that the full strength surface water from
SG-2A had not had a significant adverse impact on the reproduction of the test organism relative
to background conditions. 01 in provided the results of these bioassay tests to USEPA and R1 DEM on
August 18, 1993. No further correspondence was received from USEPA or R1 DEM regarding either
these results or requests for additional assessment of environmental conditions at the site.
Conclusions
01 in has conducted those environmental site assessment activities requested by R1 DEM in their
letter dated March 5, 1991 and outlined in the 01 in July 23, 1991 letter. The results of the artificial
substrate sampling were inconclusive; however, subsequent bioassay toxicity testing of surface water for
macroinvertebrate receptors has shown that exposure to surface water from the site does not have toxic
effects on these organisms for short- or long-term exposure.
Overall, the results of the environmental assessment activities conducted at the site
since the issuance of the ROD in April 1991 do not indicate that there were or had been
any significant effects to the environment and ecological receptors at or in the vicinity of
the Western Sand & Gravel site.
Concentrations of VOCs in sediment and surface water in samples collected in support of the R1 and in
1991-1992 did not exceed the environmental chronic toxicity screening levels that had been identified in
the R1 (Table 6.22). Further, concentrations of chemicals in groundwater at the site have also decreased
substantially since these assessment activities were conducted and as shown in Table 1, maximum
concentrations of VOCs detected in groundwater in the most recent sampling rounds (fall 2017
and spring 2018) are below the current ecological surface water screening values for hazardous
waste sites (USEPA, 2018). Since current concentrations of VOCs in groundwater are below
ecological surface water screening values, groundwater discharging to surface water (with
subsequent additional dilution by surface water) would result in VOCs concentrations in surface
water that are below ecological surface water screening values.
91
-------
Attachments
Table 1: Comparison of Recent Groundwater Data to Ecological Surface Water Screening
Values
Attachment 1: Figure 2.1 from the June 1990 R1 Report (annotated)
References
BCM, 1992a. 1991 Macroinvertebrate Study of Tarkiln Brook. Western Sand and Gravel Site,
Burrillville and North Smithfield Township, Rhode Island. March 1992.
BCM, 1992b. Spring 1992 Study of Tarkiln Brook. Western Sand and Gravel Site, Burrillville and
North Smithfield, Rhode Island. August 1992.
BCM, 1993a. Tarkiln Brook Bioassessment Sampling (1992). Western Sand and Gravel Site,
Burrillville, Rhode Island. Prepared for USEPA Region 1 and R1 DEM. August 1993.
BCM, 1993b. Sampling and Field Screening of Tarkiln Brook Sediment (1992). Western Sand
and Gravel Site, Burrillville, Rhode Island. Prepared for USEPA Region 1 and R1 DEM.
August 1993.
USEPA, 2018. Region 4 Ecological Risk Assessment Supplemental Guidance. Table la.
Surface Water Screening Values for Hazardous Waste Sites. March 2018.
https://www.epa.q0v/sites/production/files/2018-
03/documents/era regional supplemental guidance report-march-2018 update.pdf.
92
-------
Table 1: Comparison of Recent Groundwater Data to Ecological Surface Water Screening Values
Volatile Organic Compounds (VOC)
CAS
Maximum Groundwater
Concentration 2018-
2022 ((.ig/L)
Surface Water
Screening
Value ((.ig/L)
Max >
Screening
Value
1.1.1 -T richloroethane
71-55-6
BDL
76
1,1 -Dichloroethane
75-34-3
BDL
410
1,1 -Dichlorocthcnc
75-35-4
BDL
130
1.2 - D i ch 1 o rocthanc
107-06-2
BDL
2000
1,4-Dioxane
123-91-1
82
22,000
No
Chlorobcnzcnc
108-90-7
BDL
25
Chloroethane
75-00-3
BDL
1,100
Chloroform
67-66-3
BDL
140
Cis-1.2-Dichlorocthcnc (1.2-cis-
Dichlorocthycnc)
156-59-2
BDL
620
Ethylbcnzcnc
100-41-4
BDL
61
Methylene Chloride
75-09-2
BDL
1500
Napthalene
91-20-3
BDL
21
Tetrachloroethene (1,1,2,2-
Tetrachloroethylene (PCE)
127-18-4
42
53
No
Toulene
108-88-3
BDL
62
Trans-1,2-Dichloroethene (1,2-
trans-Dichloroethylene )
156-60-5
BDL
558
Trichloroethene (1,1,2
T ri chl oroethyl ene)
79-01-6
5.2
220
No
Vinyl Chloride
75-01-4
37
930
No
m-Xylene
BDL
27
o-Xylene
BDL
27
Xylene (Total)
1330-20-7
BDL
27
93
-------
Appendix G
Site Photographs from Site Inspection on 12/1/2022
94
-------
Photo 1: View of capped area Photo 2: View of locked entrance to capped area
Photo 3: Fencing and Well Field
Photo 4: Stream Gauge
All photos taken 12/1/2022
95
-------
Photo 5: No Trespassing Signs at property entry points Photo 6: Quarry operations on adjacent parcel with
retaining pond of unknown origin
Photo 7:
Aerial image showing proximity of adjacent ponds to WSG capped area
Photos 5 and 6 taken 12/1/2022; Aerial photo taken Spring 2022 by State of Rhode Island
96
-------
Appendix H
Chemicals of Concern (COC) for Groundwater
97
-------
Western Sand and Gravel Superfund Site
Chemicals of Concern (COC) for Groundwater
Volatiles
Metals
Acrolein
Aluminum
Acetone
Arsenic
Benzene
Barium
Bromomethane
Bervllium
2-Butanone
Cadmium
Chlorobcnzene
Chromium
Chloroethane
Cobalt
Chloroform
Copper
Chloromethane
Lead
1,1 -Dichloroethane
Nickel
1,2-Dichloroethane
Silver
1,1 -Dichloroethene
Zinc
1.2-Dichloroethene
T rans-1,3-Dichloropropene
Semivolatiles
Ethvlbenzene
Benzoic Acid
Methylene Chloride
B i s( 2 -cth v 1 he x v 1) Ph thai ate
4-Methyl-2-pentanone
1.2-Dichlorobenzene
1,1,2,2-Tetrachloroethane
1.4-Dichlorobenzene
T etrachloroethene
Di-n-Octvl Phthalate
T richlorofluroethene
Di-n-Butvl Phthalate
TrichlorofluoromethaJie
Isophorone
Xvlene
4-Methvlphenol
Vinvl Chloride
2-Methvlnapthalene
Napthalene
1.2.4-Trichlorobenzene
N-Nitrosodiphenvlamine
98
-------
Interim Cleanup Levels
Western Sand & Gravel Superfund Site
Chemical
Reference Dose (Oral)
mg/kg/day
Carcinogenic Potency
Factor (oral)
mg/kg/day1
Interim Cleanup Level (mg/L)
Basis
Cancer Risk Level
Noncancer Hazard Index
Noncancer Target End point
Volatile Organic Compounds (VOC)
Acetone
1.0x10 1
3.5
HB
l.OxlO"00
liver, kidney
Benzene
2.9x10 2
0.005
MCL
4.2x10 6
2-Butanone
5.0x10 2
1.8
HB
1.0x10"°°
fetotoxicity
Chlorobenzene
2.0x10 2
0.1
PMCLG
1.5x101
liver, kidney
Chloroform
l.OxlO"2
6.1x10 3
0.1
MCL
1.8x10 5
2.9x101
liver, kidney
Chloromethane
1.3x10 2
0.003
RB
l.lxlO5
1,1-Dichloroethane
1.0x10 1
3.5
HB
1.0x10™
none
1,2-Dichloroethane
9.1x10 2
0.005
MCL
1.3xl05
1,1-Dichloroethene
9.0x10 3
6.0x10 1
0.007
MCL
1.2x10"
2.3x10 2
liver
l,2-Dichloroethenea
2.0x10 2
0.07
PMCLG
1.0x101
blood
Ethylbenzene
1.0x10 1
0.7
PMCLG
2.0x101
liver, kidney
Methylene Chloride
e.oxio2
7.5x10 3
0.005
MCL
1.1x10 s
2.4x10 3
liver
4-Methyl-2-pentanone
1.0x10 1
1.8
HB
l.OxlO400
liver, kidney
Tetrachloroethene
1.0x10 2
5.1x10 2
0.005
MCL
7.4x10 6
1.5x10 2
liver
Toluene
2.0x10 1
1
MCL
1.5x101
organ weight
trans-l,3-Dichloropropene
3.0x10"
1.8x10 1
0.005
DL
2.6x10 5
4.8x101
organ weight
1,1,1-T richloroethane
9.0x10 2
0.2
MCLG
6.4x10 2
liver
1,1,2-Trichloroethane
4.0x10 3
5.7x10 2
0.003
PMCLG
5.0x10 6
2.2x10 2
clinical chemistry
Trichloroethene
l.lxlO2
0.005
MCL
1.6x10 5
Xylene
2.0E+00
10
PMCLG
1.5x101
body weight, mortality
Vinyl Chloride
1.9x10"°
0.002
MCL
l.lxlO4
Bromomethane
1.4x10 03
0.035
HB
7.3x101
stomach
1,1,2,2-T et rachlo roethane
2.0x10 1
0.001
DL
Chloroethane
14
HB*
l.OxlO4"3
blood, CNS
Acrolein
CAN
Trichlorofluoromethane
3.0x10 1
10
HB
9.7x101
mortality
99
-------
Interim Cleanup Levels
Western Sand & Gravel Superfund Site
Chemical
Reference Dose
(Oral) mg/kg/day
Carcinogenic Potency
Factor (oral)
mg/kg/day1
Interim Cleanup
Level (mg/L)
Basis
Cancer Risk Level
Noncancer Hazard
Index
Noncancer Target
Endpoint
Semi-Volatile Organic Compounds (SVOCs)
Benzoic Acid
4.0x10^°
140
HB
1.0xl0+co
irritation, malaise
bis(2-ethylhexyl)phthalate
2.0x10 2
1.4x10 2
0.004
PMCL
1.6x10 6
5.8x10 3
liver
Isophorone
2.0x101
4.1X10"3
0.0084
RB
1.0x10 6
1.2x10 3
kidney
2-Methylnapthalene
CAN
4-Methylphenol
5.0x10 2
0.18
HB
l.OxlO"1
neurotoxicity
Napthalene
4.0x10 3
0.14
HB
1.0xl0+0°
body weight
N-nitrosodiphenylamine
4.9x10 3
0.01
DL
1.4x10"6
1,2,4-Trichlorobenzene
1.3xl0"3
0.009
PMCLG
2.0x101
blood
1,2,-Dichloro benzene
9.0x10 2
0.6
PMCLG
1.9X10"1
liver
1,4-Dichlorobenzene
2.4x10 2
0.075
MCLG
5.2xl0"5
Di-n-octyl phthalate
2.0x10 2
0.7
HB
1.0xl0+0°
liver, kidney
Di-n-butyl phthalate
1.0x10 1
0.004
PMCL
1.2X10"3
mortality
Metals
Aluminum
0.05
SMCL
Barium
7-OxlO"2
1
PMCLG
4.1x101
blood pressure
Cobalt
CAN
Lead
0.005
PMCLG
Nickel
2.0x10 2
0.1
PMCLG
1.5x10 1
body organ weight
Silver
3.0x10 3
0.09
SMCL
8.7x10 1
argyria - skin
Zinc
2.0x10 1
5
SMCL
7.3x101
blood
This tobie was recreated using Table 15 of the Record of Decision. In the event of discrepancies, the ROD will be considered the correct and final version
Notes:
MCL - Maximum Contaminant Level
PMCL-Proposed Maximum Contaminant Level
MCLG - Maximum Contaminant Level Goal
PMCLG - Proposed Maximum Contaminant Level Goal
SMCL - Secondary Maximum Contaminant Level
RB - Risk Based (carcinogens)
HB - Hazard Based (non-carcinogens)
HB * - The clean-up level for chloroethane is based on the RfD for chlorobutane. The structural similarity is assumed
CNA - Criteria Not Available
RSD - Risk Specific Dose
DL - Detection Limit
NA - None Available
Chloroform* -TheMCL for total Trihalomethanes was used for Chloroform
a Since the specific 1,2-Dfchloroethene isomer was not identified in the Rl report, the MCL for the cis isomer is cited. The cleanup level may be over protective if the isomer detected is the "trans" isomer"
100
-------
Appendix I
Public Participation and Outreach
Figure 1: Western Sand & Gravel Five-Year Review Press Release
101
-------
SSI An official website of the United States government
i"i%* United States
Environmental Protection
M » Agency
Search EPA.gov
News Releases; Region §1
CONTACT US
EPA to Review Cleanups at Four Rhode
Island Superfund Sites this Year
January 18,2023
Contact Information
David Deegan {deegan.dave@epa.gov)
(617) 918-1017
BOSTON (Jan. 18,2023) - The U.S. Environmental Protection Agency (EPA) will conduct comprehensive
reviews of completed cleanup work at four National Priority List (NPL) Superfund sites in Rhode Island this year.
The sites will undergo a legally required Five-Year Review to ensure that previous remediation efforts at the
sites continue to protect public health and the environment.
"Throughout the process of designing and constructing a cleanup at a hazardous waste site, EPA's primary goal
Is to make sure the remedy will be protective of public health and the environment, especially for communities
that have been overburdened by pollution," said EM New England Regional Administrator David if. Cash. "It
is important for EPA to regularly check on these sites to ensure the remedy is working properly and Rhode
island communities continue to be protected,"
The Superfund Sites where EPA will conduct Five-Year Reviews in 2023 are listed below with web links that
provide detailed information on site status as well as past assessment and cleanup activity. Once the Five-Yea r
Review is complete, its findings will be posted to the website in a final report.
Five-Year iewfews of Superfund sites in Rhode Island to bo completed in 2023:
Central Landfill, Johnston
Plcillo Farm, Coventry
Western Sand & Gravel, BurrfUvi lie/North Smithleld
Federal Facility
Davtsville Naval Construction Battalion Center, North Kingston
102
-------
Mora information:
The Superfund program, a federal program established by Congress In 1980, investigates and cleans up the
most complex, uncontrolled, or abandoned hazardous waste sites In the country and EPA endeavors to
facilitate activities to return them to productive use. In total, there are 123 Superfund sites across New England,
Superfund and other cleanup sites in New England «*tips^/epa,6o*/aiperfunel/searcli-super(unMtts-*ihere-you-li»»'
ERA'S Superfund program
Contact Us to ask a question, provide feedback, or report a problem.
LAST UPDATED ON JAKUARY18,2023
103
------- |