FOURTH FIVE-YEAR REVIEW REPORT
FOR
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT, HARTFORD COUNTY
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Prepared by
U.S. Environmental Protection Agency
Region 1
BOSTON, MASSACHUSETTS
Digitally signed by
BRYAN OLSON
Date: 2020.09.21
08:56:58 -04'00'
Bryan Olson, Director Date
Superfund and Emergency Management Division
U.S. Environmental Protection Agency - Region 1
BRYAN
OLSON
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Table of Contents
LIST OF ABBREVIATIONS & ACRONYMS. 2
I. INTRODUCTION..,...,........,...,,.......,..........,.......,,, 4
FIVE-YEAR REVIEW SUMMARY FORM... 6
II. RESPONSE ACTION SUMMARY 6
Basis for Taking Action......................................... 6
Response Actions...,..., 7
Status of Implementation 8
IC Summary Table............................ 10
Systems Operations/Operation & Maintenance..,.. 10
III. PROGRESS SINCE THE LAST REVIEW 11
IV. FIVE-YEAR REVIEW PROCESS 12
Community Notification, Involvement & Site Interviews 12
Data Review......................................................... 12
Site Inspection........ 14
V. TECHNICAL ASSESSMENT 15
QUESTION A: Is the remedy functioning as intended by the decision documents? 15
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? 17
QUESTION C: Has any other information come to light that could call into question the
protectiveness of the remedy? 22
VI. ISSUES/RECOMMENDATIONS 22
OTHER FINDINGS............................................... 22
VII. PROTECTIVENESS STATEMENT 23
VIII. NEXT REVIEW 24
APPENDIX A - Figures
APPENDIX B - Site Histoiy Chronology
APPENDIX C - Tables
APPENDIX D - Summary of Institutional Controls
APPENDIX E - Log of Interviews
APPENDIX F - Revised OSL Trend Analysis and Information Update Technical memorandum
APPENDIX G - Site Inspections
APPENDIX B - Reference List
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LIST OF ABBREVIATIONS & ACRONYMS
ALM
Adult Lead Methodology
ARAR
Applicable or Relevant and Appropriate Requirement
BLL
Blood lead level
CD
Consent Decree
C&E
Chuck & Eddie's Salvage Yard
CERCLA
Comprehensive Environmental Response, Compensation, and Liability Act
CFR
Code of Federal Regulations
CTDEEP
Connecticut Department of Energy and Environmental Protection
CTDPH
Connecticut Department of Public Health
CT RSRs
Connecticut Remediation Standard Regulations
DCE
cis-1,2-dichloroethene
ELURs
Environmental Land Use Restrictions
EPA
United States Environmental Protection Agency
ERA
Ecological Risk Assement
EPCs
Exposure point concentrations
FYR
Five-Year Review
HHRA
Human Health Risk Assessment
IEUBK
Integrated Exposure Uptake Biokinetic Model
ICs
Institutional Controls
MIBK
methyl isobutyl ketone
MCL
Maximum Contaminant Level
NCP
National Oil and Hazardous Substances Pollution Contingency Plan
NPL
National Priorities List
LNAPL
Light non-aqueous phase liquid
O&M
Operation and Maintenance
ou
Operable Unit
PCBs
Polychlorinated bipheny Is
PCE
Tetrachloroether
PFAS
Per- and polyfluoroalkyl substances
PFBS
Perfluorobutanesulfonic Acid
PFOA
Perfluorooctanoic acid
PFOS
Perfiuorooctattesulfonic acid
PRP
Potentially Responsible Party
PSDs
Performing Settling Defendants
RACE
Remedial Action Completion Report
RAO
Remedial Action Objectives
RCRA
Resource Conservation and Recovery Act
RID
Reference Dose
ROD
Record of Decision
RPM
Remedial Project Manager
SSDA
Semi-solid disposal area
TBC
To be considered
TCA
1,1,1 -trichloroethane
TCE
trichloroethylene
UU/UE
Unlimited use and unrestricted exposure
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VC CT RSR Volatilization Criteria
VISLs Vapor Intrusion Screening Levels
VOCs Volatile organic compounds
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I. INTRODUCTION
The purpose of a Five-Year Review (FYR) is to evaluate the implementation and performance of a
remedy in order 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 FYR 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 FYR pursuant to the Comprehensive
Environmental Response, Compensation, and Liability Act (CERC-LA) Section 121, consistent with the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP)(40 CFR Section
30Q,430(f)(4)(ii)) aid considering EPA policy.
This is the fourth FYR for the Old Southington Landfill Superfund Site (Site). The triggering action for
this statutory review is the date of the previous FYR. The FYR has been prepared due to the fact that
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 two operable units (OUs) reviewed in this FYR. OU1 addresses the landfill cap with
all of its appurtenances and OU2 addresses downgradient vapor intrusion from groundwater migrating
off-site.
The Site FYR was led by EPA. Participants included Almerinda Silva (Remedial Project Manager),
Ruthanne Sherman (Senior Enforcement Counsel), Christopher Kelly (Hydrogeologist), Courtney
Carroll (Human Health Risk Assessor), Bart Hoskins (Ecological Risk Assessor), Darriel Swatts
(Community Involvement Coordinator), and Steven Gaura (CT DEEP Project Manager). The review
began on November 18, 2019.
Site Background
The 13-acre Site is located in Southington, Connecticut, approximately 13 miles southwest of Hartford,
Connecticut (Appendix A» Figure 1). From 1920 to 1967, local residents and area businesses used
portions of the landfill for disposal of waste materials. During this time frame, the landfill was known as
the Old Turnpike Landfill. The northern and southern portions of the landfill were used for distinct and
separate purposes. The northern portion of the landfill was a "stump dump" used for the disposal of wood
and construction debris. The southern portion of the landfill was used as co-disposal of municipal and
industrial waste. Historical information, interviews with current and past Town employees, and
information contained in public documents on disposal practices indicate that from (1964-1967) two semi-
solid disposal areas (SSDA 1 and SSDA 2) in the southern portion of the landfill (Figure 2) were used for
disposal of such wastes. In 1967 (or shortly thereafter), the landfill was "closed" consisting of: compacting
disposed material, covering with 2 feet of clean fill, and seeding for erosion control.
Between 1973 and 1980, the landfill property was subdivided and sold for residential and commercial
development. Several residential and commercial buildings were built on the Site and on adjacent areas.
The landfill is located approximately 700 feet southeast of the former Production Well No 5, (Well No.
5) (Figure 2), which was installed in 1965 by the Town of Southington Water Department and was used
as a public water supply. The Connecticut Department of Public Health and Addiction Services (CT
DPH), sampled Well No. 5 on several occasions between December 1978 and March 1979. Analyses of
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the samples indicated the presence of chlorinated volatile organic compounds (VOCs). Because of the
detection of 1,1,1-trichloroethane (TCA) at levels that exceeded State standards, Well No. 5 was
permanently closed in August 1979.
Current Land Use
The landfill is currently capped. The northern portion of the landfill is accessible for passive recreational
use. The southern portion of the landfill is fenced and locked. Access by Performing Settling Defendants
(PSDs) is primarily for landscaping and general operations and maintenance (O&M) of the capped
landfill. The Chuck & Eddie's Used and New Auto Parts Property (C&E) is home to an active used
automotive parts business and salvage yard. Entry into the salvage yard is limited by some barriers and
access into the yard by the public is through the main office building. A network of monitoring wells
(G302A; G303A; G304A, B, €; G312A, B, C; G313A; GZ-5M, S) used in the Cap Effectiveness long-
term monitoring program, are located along the eastern perimeter of this property. The Radio Station
Property is home to an active radio station, WNTY 990 AM. Access to the property is open to the public
and monitoring wells are located along the southern perimeter of this property (EPA, 2018).
In 2018, the Town and PSDs entered into discussions with Symbiont Energy into the construction of a
solar farm on the landfill Site. The installation of a passive ballasted solar system was discussed in
December 2018. At this time no additional information is available regarding the possible re-
development of and/or the future use of the Site as a solar farm.
A more detailed description of the Site history can be found in Section 1 of the Supplemental Remedial
Investigation Report (Kleinfelder, May 2006) and in the Remedial Action Completion Report, Old
Southington Landfill, Southington, Connecticut (Loureiro, June 2018). See Appendix B for Site history
chronology.
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FIVE-YEAR REVIEW SUMMARY FORM
II. RESPONSE ACTION SUMMARY
Basis for Taking Action
The basis for taking corrective action at the Site included human health risk.
• Human Health Risk Assessment - A human health baseline risk assessment (HHRA) was
performed as part of the 1993 Remedial Investigation/Feasibility Study (RI/FS) for the Site. Risk
assessment calculations indicated that major contributors to carcinogenic risk estimates in
groundwater included trichloroethene, vinyl chloride, beryllium, arsenic,
bis(2-ethylhexylphthalate) and polychlorinated biphenyl (PCB) aroclors. Major contributors to
non-carcinogenic risk estimates included antimony, barium, bis(2-ethylhexyl) phthalate,
cadmium, chromium, 1,2-dichloroethene, ethyl benzene, nickel, silver, thallium, toluene,
vanadium, arsenic, manganese, zinc, and PCB aroclors. Maximum Contaminant Level (MCLs)
in groundwater were exceeded for approximately 20 compounds. A presumptive remedy
approach for capping the landfill was pursued to address potential contact or ingestion from soils
or landfill wastes.
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• At the time of the signing of the OU1 Record of Decision (ROD) for the Site, the groundwater
aquifer at tie leading edge of the VOC plume near the Quinnipiac River was classified by CT
Department of Energy and Environmental Protection (CT DEEP) as "GA", acceptable for human
consumption. Therefore, from a risk assessment standpoint, those groundwater contaminants that
were relatively mobile were of particular concern. CT DEEP has since classified the
groundwater within the study area (between, the landfill and the Quinnipiac River) as "GB",
which indicates that the groundwater is not suitable for use as a drinking water supply.
• Shallow groundwater depth for this Site is defined as 30 feet below ground surface. Groundwater
contaminated with VOCs may impact buildings through vapor intrusion that could potentially
migrate through sub-slabs or basements. Thus, occupants of structures overlying shallow
groundwater contamination may potentially be exposed to VOCs originating from the shallow
groundwater. The vapor intrusion exposure pathway was evaluated by comparing VOC
concentrations in the shallow groundwater aquifer to the CT Remediation Standard Regulations
Volatilization Criteria (CT RSRs VCs).
• Ecological Risk Assessment As part of the 1993 RI/FS, an ecological risk assessment (ERA)
was conducted at the Site and also for a limited area in the near field relative to the landfill. The
ERA delineated and evaluated sediment, conducted a qualitative animal survey, and completed
an ecological hazard assessment. The results of the ERA indicated no unacceptable risk to the
environment.
Response Actions
• CT DPH sampled Town of Southington groundwater Production Well No. 5 on several occasions
between December 1978 and March 1979. Well No. 5 was located approximately 700 feet north-
northwest of the Southington Landfill. Results of this sampling effort indicated that the well was
contaminated with chlorinated organic compounds including trichloroethylene (TCE) and TCA.
Based on these results, the well was closed in August 1979. In November 1980, CT DEEP
collected and analyzed soil samples from a manhole that was located in the industrial park that
was built on the landfill. Both chlorinated and non-chlorinated VOCs were detected in the soil
samples.
• In September 1984, CT DEEP signed a Consent Order with the Town of Southington under
which the town was required to investigate a portion of the contamination at the landfill.
Subsequently, in 1992, a consent order was reached between the Town of Southington and CT
DEEP. The Town of Southington implemented a landfill gas monitoring and mitigation plan at
the Site.
• In September 1987, three Potentially Responsible Parties (PRPs), the Town of Southington, Pratt
and Whitney division of United Technologies Corp. (now known as Raytheon Technologies
Corp.), and Solvents Recovery Service (SRS) of New England, Inc., signed an Administrative
Order by Consent to perform an RI/FS at the Site.
Two RODs were issued for the Site. The 1994 ROD for the Interim Remedial Action for Limited Source
Control (OU1) was for a presumptive soil remedy. The 2006 Final ROD (OU2) was for conducting
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additional groundwater studies to determine the extent of the groundwater plume and any respective
potential impacts to human health and natural resource areas.
The 2006 Final ROD established the following remedial action objective (RAO). Prevent inhalation of
VOCs by occupants of residential/commercial/industrial buildings resulting from volatilization ofVOCs
in groundwater, in excess of 10"4 to 10"6 excess cancer risk, a hazard index >1 and/or to comply with
applicable or relevant and appropriate volatilization criteria. This RAO is being met through the
implementation of the ICs which includes regular monitoring/inspections and mitigation measures as
necessary. Attainment of groundwater restoration cleanup levels is not an RAO at this Site. The final
groundwater remedy is not designed to clean up or restore groundwater but to address potential risks
from vapor intrusion into buildings located above shallow groundwater contaminated from the Site
(EPA, 2006).
Status of Implementation
• The remedy for the 1994 ROD (OU1) was completed in September 2001 and consisted of the
following remedial components:
o Permanent relocation of four residences from the northern part of the landfill and six
businesses from southern part of the landfill;
o Installation of a RCRA Subtitle C Landfill Cap on the southern, formerly commercial,
part of the landfill;
o Installation of a RCRA Subtitle D Landfill Cap on the northern, formerly residential,
portion of the landfill;
o Excavation and consolidation of semi-solid disposal area #1 (SSDA #1) referred to as a
hotspot area into a lined cell above the groundwater table and underneath the RCRA
Subtitle C Cap;
o Installation of a passive soil gas collection and venting system throughout the entire
landfill area;
o Building of a passive recreational park on the northern, formerly residential, part of the
landfill;
o Performance of long-term monitoring;
o O&M of the landfill cap along with its appurtenances;
o Development of institutional controls (ICs) including fencing;
o Performance of FYRs; and
o Additional groundwater studies
• Following negotiations, a Consent Decree (CD) between EPA, CT DEEP, and the Performing
Settling Defendants (PSDs) was lodged in the United States District Court in March 1998.
Although not initially required under the 1994 ROD for the cap remedy, based on further landfill
gas vent evaluations and a helium tracer test, the PSDs installed a trench with an impermeable
gas barrier along the northern perimeter of the landfill in December 2009 (Figure 3). The barrier
was installed to prevent potential landfill gases from migrating off site to the residential
neighborhood located immediately north of the landfill Site.
• Based on additional groundwater studies, the OU2 Final ROD was issued in 2006. The OU2
ROD set forth the final selected remedy to address potential human health risks from vapor
intrusion that may enter into buildings situated above the shallow groundwater VOC plume.
This component of the final remedy complemented the OU1 ROD's Interim Remedial Action for
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Limited Source Control. The OU2 remedy also included pre-design investigations to further
evaluate potential vapor intrusion threats from shallow groundwater VOCs to downgradient
properties,
• Two construction activities related to the 2006 ROD were completed, including the
implementation of ICs in the form of environmental land use restrictions (ELURs) at the C&E
property and Radio Station property, as well as the installation of a vapor barrier beneath the
concrete floor of a new building constructed on the C&E property which prevents vapor
intrusion risk to workers in the building.
• Remedial components of the 2006 ROD included ICs in the form of ELURs as defined in the CT
RSRs on properties or portions of properties where groundwater VOC concentrations exceed CT
DEEP's volatilization criteria (VC). These properties included the C&E and Radio Station
properties located across Old Turnpike Road and downgradient of the Site (Figures 4). The
ELURs will remain in place as long as groundwater VOC concentrations exceed the criteria.
Periodic inspections will be performed on a biennial basis to ensure compliance with the ELURs
and to ensure notification to EPA, CT DEEP, and the appropriate local governmental agencies if
the ELUR is breached or compromised.
• In addition, building ventilation controls will be used to either prevent migration of VOC vapors
into buildings, or to control the level of VOCs in vapors beneath existing buildings, (sub-slab
depressurization or similar technology) as appropriate. Similarly, vapor barriers (or similar
technology) will be used to control vapors in new buildings. Operation, maintenance, and
monitoring of engineered controls and ICs will ensure remedial measures are performing as
intended, and continue to protect human health and the environment in the long-term. No
building ventilation controls were required in any areas downgradient of the Site. However, two
vapor barriers were installed beneath the Quonset hut building constructed on the C&E property:
one below the footings in 2010, and the second in 2011 before the concrete slab was poured.
• All RAOs are being met for the site. On September 12, 2018, the Site was deleted from the
National Priorities List (NPL) EPA determined, and CT DEEP concurred, that all appropriate
Superfund-financed responses under CERCLA, have been implemented and that no further
cleanup by responsible parties is necessary for the Site. The PSDs will continue to perform O&M
activities along with long-term monitoring and EPA will continue to perform FYRs. Long-term
monitoring and FYRs will continue to assure that remedial actions conducted at the Site to date
continue to be protective of public health and the environment. This deletion does not preclude
future actions under Superfund, if warranted.
Institutional Controls
Institutional controls (ICs) have been implemented at all properties that comprise the Site (the
landfill, the C&E property, and the Radio Station property) to prevent consumption of
contaminated groundwater, prevent activities that would compromise the integrity of the landfill
cap, and restrict construction of structures over contaminated groundwater that exceed state
groundwater standards with regard to preventing vapor intrusion exposures. These ICs address
the requirements of both the 1994 and 2006 RODs. The ICs are environmental restrictions in the
forms of "Declarations of Land Use Restrictive Covenants (Environmental Restriction)" and
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"Declarations of Environmental Land Use Restrictions (ELURs)" See Appendix C, Table 4
and Appendix D for more details.
1C Summary Table
Table 6: Summary of Implemented TCs in i
ie form ol'Declaration of Land Use Restrictive (,'ovcnanls
Ml-iIm.
i ii>_:jhi 4 nil
oniin..k
areas that do not
siippun f 1 1. i
based on current
CO)l<1 il Kills
ICs
Vtilof
ICs Called
for in the
iViM.-ii!
Ofit ¦IIHi'll!"
i'ijiiiinl
IC
t )hji i. ji'i
Title oflC
lni|ilriiH'
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used to determine the vapor intrusion potential of tie current groundwater plume, A Mann-
Kendall analysis of groundwater VOC results from 2015 through 2019 indicate that groundwater
plume is generally stable. Considering tie current geographic layout of the active monitoring
well network and the continued detections of VOCs above their respective MCLs, a reduction, in
sampling frequency or distribution will not be instituted at this time. As new analytical data is
made available, EPA, in collaboration with the PSDs, will explore options for optimizing the
groundwater monitoring program.
III. PROGRESS SINCE THE LAST REVIEW
This section includes the protectiveness determinations and statements from the last five-year review as
well as tie recommendations from the last five-year review and the current status of those
recommendations.
Table 7: Protectiveness Determinations/Statements from the 2015 FYR
ou#
Protectiveness
Determination
Protectiveness Statement
1
Protective
The remedy at OU1 is protective of human health
and the environment. All exposure pathways that
could result in unacceptable risks have been
addressed and the components of the OU1 1994
remedy are functioning appropriately. The landfill
cap effectively prevents dermal contact with landfill
contaminants. Removal of commercial and
residential structures in conjunction with the landfill
cap construction has further supported overall
protectiveness. CT DEEP has reclassified the
groundwater impacted by the plume to a GB (non-
potable) aquifer and everyone in the area is
connected to municipal water, thus, eliminating the
potential for groundwater ingestion or dermal risk.
The long-term protectiveness of the remedial action
at the Site will continue to be verified through the
monitoring programs.
2
Short-term Protective
The OU2 2006 ROD is currently protective.
Monitoring will continue at certain parcels to ensure
long-term protectiveness should land use conditions
change in the future. In order to achieve long-term
protectiveness, ICs must be implemented at the
C&E property and the Radio Station property.
Sitewide
Short-term Protective
The remedy at the Old Southington Landfill Site is
currently protective of human health because all
exposure pathways that could result in unacceptable
risks have been addressed. The landfill cap has
effectively prevented dermal contact with landfill
contaminants, on-site residents and businesses were
relocated from the landfill, urountiwaicr was
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reclassified by the state to eon-potable, and
everyone in the area is connected to municipal
water thereby eliminating the potential for
groundwater ingestion or dermal contact. Site-wide
long-term monitoring continues. The OU2 remedy
currently protects human health and the
environment. In order for the remedy to be
protective in the long-term, ICs must be finalized at
the C&E and at Radio Station properties.
Table 8: Status of Recommendations from the 2015 FYR
OH
#
Issue
Recommendations
Current
Status
Current Implementation
Status Description
Completion
Date (if
applicable)
OU2
IC for Vapor
Intrusion
PSDs finalize
placing ICs at the
Radio Station
property and at the
C&E property.
Completed
At the Radio Station property
(comp 1 eted 4/17/2017) and
at C&E Property (completed
6/22/2017)
6/22/2017
IV. FIVE-YEAR REVIEW PROCESS
Community Notification. Involvement & Site Interviews
Per Region 1 policy, a region-wide press release announcing all upcoming FYRs in New England was
sent to all regional newspapers. The one for Connecticut was sent on 3/13/2020 and can be accessed at
https://www.epa.gov/iiewsrelea.ses/epa-beains-reviews-three-conitecticnt-suDerfniid-site-cleaniiPS-vear.
The results of this report will be posted to www.epa.gov/superfund/oldsouthington.
During the FYR process, interviews were conducted by Almerinda Silva to document any perceived
problems or successes with the remedy that has been implemented to date. The general consensus from
the nearby residents was as follows. With the exception of some overgrown vegetation in the swale area
adjacent to Black Pond, the landfill itself looks good. No other complaints were voiced. Mr. Steve
Gaura, CT DEEP Project Manager, Mr. Mark Sciota, Southington Town Manager, and Mr. Joseph
Trzaski, Senior Project Scientist, from Loureiro Engineering Associates Inc., technical consult for the
PSDs were also interviewed. Complete interviews can be found in Appendix E.
Data Review
Semi-annual sampling of the monitoring well network is performed to assess the groundwater quality
downgradient of the Site. Sampling results from March 2015 through September 2019 (a total of 10
sampling events) were reviewed for this FYR. Sampling results presented in the current cap
effectiveness monitoring report indicate the continuing presence and elevated concentrations of multiple
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VOCs, including chlorinated ethenes, chlorinated ethanes, aromatic hydrocarbons, and ketones in
multiple wells in the monitoring network (Loureiro, 2019). Although some of the groundwater
concentrations exceed the Connecticut regulations for Groundwater Volatilization Criteria, the potential
threat due to vapor intrusion was addressed by the PSDs' 2011 investigations, which indicated vapor
intrusion did not pose unacceptable risks to human health at the Site (Loureiro, 2012). Additionally, the
aquifer downgradient of the capped landfill is classified as GB and is therefore unsuitable for use as a
potable supply, farther ensuring the protectiveness of the remedy.
Groundwater monitoring is the primary method performed to evaluate landfill cap effectiveness.
Statistical analysis was performed to evaluate temporal trends of chemical concentrations in
groundwater. Groundwater chemistry data were initially evaluated on a well-by-well basis and them
combined based on the depth of the screened interval (i.e., shallow, medium and deep). Appendix F
presents the trend analysis using the Mann-Kendall and the Regional Kendall statistical analyses.
Chemical trends were evaluated for benzene, chloroethane, cis-l»2-dichloroethene (DCE), ethylbenzene,
tetrachloroethylene (PCE), trichloroethylene (TCE), vinyl chloride and total xylenes. Select wells were
also evaluated for a combination of acetone; 1,2-dichloroethane (1,2-DCA); 1,1-dichloroethane (1,1-
DCA); methyl isobutyl ketone (MIBK); toluene; trans-1,2-dichloroethene (trans-1,2-DCE); and
tetrahydrofuran.
As presented in the summary of the Mann-Kendall analyses (Table 1), there were no statistically
significant trend changes in concentrations during the 2015 to 2019 observation period for the majority
of VOCs evaluated. Increasing trends were noted in wells G304A (vinyl chloride), G312B (PCE), and
GZ-5M (benzene). Table 2 shows all the significant concentration changes for each well.
Table 3 presents the concentration trends by aquifer depth (shallow, intermediate, and deep). When
grouped by depth, VOC concentration showed no statistically significant change in concentration trends.
These results are not surprising given the high frequency of non-detects (i.e., low frequency of detects)
observed for many VOCs throughout the three intervals evaluated.
Monitoring well G303A (shallow) had several spikes in vinyl chloride concentrations (Appendix F),
which account for the statistical "no trend" for this VOC. No other VOCs were routinely detected at well
G303A.
Monitoring well G304A (shallow) continues to exhibit the greatest number of VOCs detected at elevated
concentrations with vinyl chloride concentrations increasing between 2015 and 2019. Decreasing trends
of ethylbenzene and total xylene concentrations are noted. The spike in chlorinated VOC concentrations
(specifically cis-1,2-DCE and TCE-eqiiivalents) in G304A coincide with a decrease in groundwater
elevations (Loureiro, 2019). A light non-aqueous phase liquid (LNAPL) was reported in G304A with
apparent thicknesses of 0.18 ft in March 2018 and 0.01 feet in September 2019. LNAPL has been
sporadically detected in this monitoring well since 2002. G304A is located immediately downgradient
SSDA-1, which also had an apparent thickness of 0.01 feet of LNAPL present-
Monitoring well GZ-5M (intermediate) located near G304A, continues to exhibit fluctuating
concentrations of VOCs. Cis-1,2-DCE concentrations decreased between September 2015 and March
2019, and then proceeded to increase sharply in September 2019. Benzene concentrations have been
increasing between 2015 and 2019 while chloroethane concentrations have been consistently
decreasing. Vinyl chloride concentrations appear to be stable during the last five years.
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Monitoring well GZ-5S (shallow) exhibited statistical increases on cis-l,2-DCE and TCE between
September 2016 and September 2018, but concentrations decreased in March 2018 and have remained
relatively low since, TCE and DCE concentrations are consistently lower in in GZ-5S than in GZ-5M.
Monitoring well G312B (intermediate) exhibited a statistical increase in PCE concentrations between
March 2015 and September 2019, and probable increases of TCE during the same time period. Prior to
September 2017, TCE had not been detected in G312B since December 2006.
Monitoring well G312C (deep) exhibited a statistical decrease on chloroethane and probable increases
for benzene, cis-l,2-DCE, and vinyl chloride (Appendix F).
Although there have been statistical trend changes for some VOCs in select wells, this is consistent with
the nature of releases from an unlined landfill subject to fluctuating water table conditions.
Increased ratios of daughter products (e.g. cis-l,2-DCE and vinyl chloride) to parent products (e.g. PCE
and TCE) have been identified, indicating that biodegradation is occurring. The highest concentrations to
date of cis-l,2-DCE were detected in G304B, GZ-5S, and G312C between March 2017 to March 2019.
With a few exceptions, VOCs in groundwater are generally within the range of historically detected
concentrations providing evidence that the landfill cap at the Site is functioning as designed and expected.
Site Inspection
The inspection of the Site was split into two events, one conducted on September 4, 2019 and a second
on November 21,2019. Daring the September event, the Site was visited as part of the semi-annual Cap
Effectiveness groundwater sampling event and in attendance were two representatives from the PSD's
consultant Lourerio Engineering Associates (Lourerio) and James Harrington, Nobis Group. During the
November event, the landfill property, as well as, CAE's and the Radio Station properties were
inspected and in attendance were Almerinda Silva, US EPA, Christopher Kelly, USEPA, Courtney
Carroll, USEPA, Peter Hill, CT DEEP, and Joseph Trzaski, Loureiro. The purpose of the inspection was
to assess the protect! veness of the remedy.
The September 2019 site observations were performed in conjunction with oversight of the Cap
Effectiveness groundwater sampling event (Nobis, 2019). Lourerio performed groundwater sampling at
12 groundwater monitoring wells. Nobis noted no discrepancies or issues during the groundwater
sampling oversight. The landfill inspection report and photographs are included as Appendix G. The
landfill appeared to be in good overall condition. The following observations were made:
• An approximately 10-foot diameter area with minor subsidence, likely due to landfill settlement
was observed in the southern portion of the landfill, approximately 45 feet east of GV-2.
• Excessive overgrowth of vegetation was observed along the southern perimeter fence.
• Damage to the fencepost was observed opposite the entrance to C&E.
• Black Pond discharge swale was very overgrown with low-growing vegetation and the drain at the
western end of the swale was becoming overgrown, which is impeding water flow from exiting
the swale.
14
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V. TECHNICAL ASSESSMENT
QUESTION A: Is the remedy functioning as intended by the decision documents?
Yes, the remedy is functioning as Intended by the decision documents.
Remedial Action Performance
The OUl remedy continues to function as designed, Construction of the low-permeability cap
over the landfill in 2001 prevents direct contact exposures with landfill contaminants and
minimizes precipitation infiltration that could mobilize contaminants present in the waste
materials.
• Hydrogeologic investigations conducted in 2011 demonstrated that contaminated
groundwater migrating away from the Site was unlikely to enter a portion of the aquifer
designated as suitable as a public water supply (Class GA) by CTDEEP. Available data
suggest contaminants in the shallow portion of the aquifer are limited in their migration
into the deeper aquifer zones based on observed upward vertical gradients. A Mann-
Kendall analysis provided an indirect line of evidence that VOC concentrations in the
intermediate and deep aquifer zones are stable or declining, which supports the findings
of the hydrogeologic investigation.
• The installation of a gas barrier trench along the northern landfill perimeter prevents the
potential off-site migration of landfill gases to nearby residential properties. Evaluations
for the southern portion of the landfill demonstrated that the migration of landfill gases
will not pose concern for potential receptors.
• For OU2, an investigation was completed that demonstrated contamination in deeper
groundwater did not pose potential vapor intrusion concerns to residential properties in
the Highland Hills area. While VOCs were detected at depth, they were not detected in
the vadose zone beneath the residential properties. Therefore, indicating no vapor
intrusion pathway was present to pose a potential threat due to the landfill.
• For OU2, a vapor intrusion investigation was completed that evaluated VOCs in shallow
groundwater and soil gas. Results of this investigation identified vinyl chloride in
groundwater at the C&E property. In 2011, the C&E owners constructed a new building
over concrete slab foundation and installed a 40-mil HDPE geomembrane beneath the
concrete footings. In addition, a second 40-mil HDPE geomembrane was installed prior
to the pouring of the concrete slab and all penetrations were sealed. The geomembrane
seams welds were tested. The two geomembranes act as a passive vapor intrusion barrier
and is protective of the workers in the building.
15
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System Operations/OA M
O&M at the Site is performed by the PSDs. Table 5 lists the roles and responsibilities for
managing the Site after the deletion of the Site from the National Priorities List (EPA, 2018).
The effectiveness of the cap is monitored and inspected on a semi-annual basis. Additionally,
groundwater samples are collected and analyzed semi-annually (March and September). The
cover system is repaired as needed. The landfill is inspected quarterly by either the Town of
Southington or Loureiro. Prior to lime 2020, tie inspections were completed by the Town of
Southington on a monthly basis. During the reporting period the following issues were
repeatedly identified during the monthly landfill inspections:
• Black Pond discharge swale needs to be cleaned of overgrown brush/vegetation,
• South drainage swale needs to be cleared of brush/vegetation,
• Clear brush inside fence at GV1 and GVO.
• Clear brush around G304A, G303A, G302A.
• Clear brush around perimeter fence and monitoring wells off-site.
During the last five years (2015-2019) the following repairs have been performed at the Site:
• February 2019-Fence and post were repaired following a car accident that damaged the fence
between six posts at the entrance to the Loureiro Contractors Inc. (LCI) Yard. The fence was
repaired and no damage was identified to the landfill liner.
• May 2019-following the deletion of the Site from the NPL, 27 vapor probes were abandoned
in-place along Rejean Road and Amanda Lane to the north of the Site.
Implementation of Institutional Controls and Other Measures
• ICs are currently in-place for the capped landfill, as detailed in Table 4, which prohibit
future development, disturbance of the cap, use of groundwater, and require any new
structures to be constructed in accordance with a plan approved by EPA to minimize the risk
of inhalation of contaminants. ICs are also in-place for the two properties downgradient of
the landfill (C&E and the Radio Station properties) also detailed in Table 4. Landfill
inspection reports from 2015 through the end of 2019 were reviewed for this FYR and no
major issues were identified.
• Biennial site inspections of the two properties downgradient of the landfill, C&E's Property
and the Radio Station Property, are performed in accordance with the June 2018 Remedial
Action Completion Report (RACR) for the Site (Loureiro, 2018). The inspections are
performed to ensure the long-term protection of human health and the environment. The most
recently performed inspection was completed in September 2019 by Loureiro. The site
16
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inspection and building records review did not identify any potential issues with tie integrity
of tie ELURs recorded for the two properties (Loureiro, 2020) Appendix G.
QUESTION B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action
objectives (RAOs) used at the time of the remedy section still valid?
No. There have been changes to some of the exposure assumptions, exposure pathways, and toxicity
data used at the time of remedy selection, however these changes do not impact the current
protectiveness of the remedy because the installation of the low-permeability cap prevents potential
direct contact with landfill contaminants, and the 2006 ROD implemented measures to address potential
human health risks from vapor intrusion (¥1). To date, ¥1 evaluations have not identified human health
risks; however, groundwater data continues to be reviewed as recommended in the previous FYR.
Additionally, emerging issues such as PFAS may be evaluated for the Site but would not be expected to
alter remedy protectiveness because there is no use of groundwater at the Site.
The following sections describe changes that have occurred since the 2015 FYR.
Changes in Standards and TBCs
New standards should be considered during the five-year review process as part of the protectiveness
determination. Under the NCP, if a new requirement is promulgated after the ROD is signed, and the
requirement is determined to be an ARAR, the new requirement must be attained only if necessary, to
ensure that the remedy is protective of human health and the environment.
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.)
Most of the components of OU1 were performed in compliance with the action and location-specific
applicable or relevant and appropriate (ARARs) and/or To-Be-Considered (TBCs) cited in the 1994
ROD. Long-term monitoring, operations and maintenance, and FYRs continue. Because of its reliance
on preventing environmental and human exposures to contaminants through capping, removal of
buildings, and restricting Site access, the 1994 ROD set no chemical-specific clean-up standards. The
2006 ROD concluded that the actions taken under the 1994 ROD were effective in the long-term,
protective of human health, met ARARs, addressed the principal threats, and addressed the statutory
preference for treatment that reduces the toxicity, mobility, and volume. Therefore, the 2006 ROD
17
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confirmed that the components of the 1994 ROD are the final components for the remedial actions for
source control
Connecticut has not promulgated drinking water or groundwater standards for PFAS. In November
2016, CT DPH did issue a drinking water action level of 70 ng/L (ppt) for the sum of five PFAS
compounds: PFOA, PFOS, PFNA, PFHxS and PFHpA. For groundwater, without specific numbers for
groundwater protection criteria for PFAS compounds, the Connecticut Remediation Standard (22a133k-
3) require remediation using the procedures for Additional Polluting Substances (22a-133K-3(h)).
PFAS sampling has not occurred at this Site. The Site's groundwater plume sits within an aquifer that
has been reclassified by CTDEEP as non-potable, a Town ordinance prevents installation of drinking
water wells, and people are connected to municipal water. However, PFAS is an emerging contaminant
and should be included in a future sampling event.
Changes in Toxicity and Other Contaminant Characteristics
Since the 2015 FYR, there have not been any toxicity changes for Site COCs. Although PFAS and 1,4-
dioxane were not evaluated in the HHRA or identified as COCs, they are included in the discussions
below because PFAS and 1,4-dioxane are emerging issues at many NPL sites including landfills.
Additionally, since the 2015 FYR, EPA has released an updated approach to addressing lead in soils.
The updates discussed below would not alter the current protectiveness of the remedy because the
landfill cap remains intact and ICs are in place preventing exposure to Site-related contaminants.
• 2010 and 2013 1,4-dioxane cancer and non-cancer toxicity values
In 2010 and 2013, EPA finalized the toxicity assessment for 1,4-dioxane. The new values indicate that
1,4-dioxane is more toxic from both cancer and non-cancer health effects. These toxicity changes would
result in increased non-cancer hazard and cancer risk from exposure to 1,4-dioxane.
1,4-Dioxane was not assessed in the original HHRA Groundwater monitoring between 2008 and 2010
did include 1,4-dioxane, which found detections below the previous EPA screening level of 65 pg/L (the
current screening level for residential drinking water is 0.46 pg/L). However, the data is limited and
contained many non-detected results that are above the current screening level. 1,4 Dioxane should be
resampled and results compared to current screening levels. Detections of 1,4-dioxane in groundwater
will not likely alter the current protectiveness of the remedy because the remedy includes vapor
mitigation features to prevent exposure via vapor intrusion, and groundwater at the Site is not being used
as drinking water source.
• Lead in Soil Cleanups
Updated scientific information indicates that adverse health effects are associated with blood lead
levels (BLLs) at less than 10 pg/dL. Several studies have observed "clear evidence of cognitive
function decrements in young children with mean or group BLLs between 2 and 8 pg/dL." Soil
screening, action or cleanup level developed based on the previous target BLL of 10 pg/dL may not
be protective,
EPA's approach to evaluate potential lead risks is to limit exposure to residential and commercial
soil lead levels such that a typical (or hypothetical) child or group of similarly exposed children
would have an estimated risk of no more than 5% of the population exceeding a 5 pg/dL blood lead
18
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level (BLL). This is based on evidence indicating cognitive impacts at BLLs below 10 pg/dL.
Additionally, this approach aligns with the Lead Technical Review Workgroup's current support for
using a BLL of 5 pg/dL as the level of concern in the Integrated Exposure Uptake Biokinetic Model
(IEUBK) and Adult Lead Methodology (ALM). A target BLL of 5 pg/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 ng/dL and geometric standard deviation being 1.8.
Using updated default IEUBK and ALM parameters at a target BLL of 5 pg/dL, site-specific lead
soil screening levels (SLs) of 200 ppm and 1,000 ppm are developed for residential and
commercial/industrial exposures, respectively.
Lead was identified as a COC in the baseline HHRA, however the maximum concentration found in
surface soil was found to be 17? mg/kg which is below the EPA residential screening level of 200
mg/kg. Additionally, the remedy includes a cap which prevents contact with Site contaminants in soil
Therefore, this updated EPA approach to addressing lead in soil does not impact the remedy at this Site.
• 2016 PFOA/PFOS non-cancer toxicity values
In May 2016, EPA issued final lifetime drinking water health advisories for perfluorooctanoic acid
(PFOA) and perfluorooctane sulfonate (PFOS), which identified a chronic oral reference dose (RID)
of 2E-05 mg/kg-day for PFOA and PFOS (USEPA, 2016a and USEPA, 2016b). These RID values
should be used when evaluating potential risks from ingestion of contaminated groundwater at
Superfund sites where PFOA and PFOS might be present based on site history. Potential estimated
health risks from PFOA and PFOS, if identified, would likely increase total site risks due to
groundwater exposure. Further evaluation of potential risks from exposure to PFOA and PFOS in
other media at the Site might be needed based on site conditions and may also affect total site risks.
• 2014 Perfluorobutanesulfonic Acid (PFBS) non-cancer toxicity value
PFBS has a chronic oral RfD of 2E-02 mg/kg-day based on an EPA Provisional Peer Reviewed Toxicity
Value (PPRTV) (USEPA, 2014a). This RfD value should be used when evaluating potential risks from
ingestion of contaminated groundwater at Superfund sites where PFBS might be present based on-site
history. Potential estimated health risks from PFBS, if identified, would likely increase total site risks
due to groundwater exposure. Further evaluation of potential risks from exposure to PFBS in other
media at the Site might be needed based on Site conditions and can also affect total site risks.
19
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PFAS at the Old SouthingUm Landfill NPL Site
PFAS sampling has not occurred at this Site. The Site's groundwater plume site withing an aquifer that
has been reclassified by CTDEEP as eon-potable, a Town ordinance prevents Installation of drinking
water wells, and people are connected to municipal water. However, PFAS is an emerging contaminant
and should be included in a future sampling. Site history included collection of a variety of industrial
and commercial wastes which may have included PFAS, If identified, the presence of PFAS would not
likely impact current remedy protectiveness because there is no use of Site groundwater, therefore
resulting in unlikely exposure to Site contaminants in groundwater. In addition, ICs are in place for the
C&E ad Radio Station properties located downgradient of the landfill, and an investigation was
completed that demonstrated deeper groundwater did not pose potential vapor intrusion concerns to
residential properties in the Highland Hills area. Therefore, there would be no likely risk associated with
potential vapor intrusion from PFAS.
Changes in Risk Assessment Methods
Since the 2015 FYR the following changes have occurred in recommended risk assessment methods:
• 2014 OSWER Directive Determining Groundwater Exposure Point Concentrations,
Supplemental Guidance
In 2014, EPA finalized a Directive to determine groundwater exposure point concentrations (EPCs):
https://cfoub.epa.gov/'ncea/risk/recordisplav.cfm?deid=236917. This Directive provides
recommendations to develop groundwater EPCs. The recommendations to calculate the 95% UCL of the
arithmetic mean concentration for each contaminant from wells within the core/center of the plume,
using the statistical software ProUCL, could result in lower groundwater EPCs than the maximum
concentrations routinely used for EPCs as past practice in risk assessment, leading to changes in
groundwater risk screening and evaluation. In general, this approach could result in slightly lower risk or
higher screening levels. (Reference: USEPA. 2014. Determining Groundwater Exposure Point
Concentrations. OSWER Directive 9283.1-42. February 2014.)
The changes in the recommended approach to risk assessments that have occurred since the 2015 FYR
do not affect the protectiveness of the remedy because exposure to site contaminants is prevented by the
cap and ICs prevent use of groundwater.
Changes in Exposure Pathways
No changes in exposure pathways were identified for ecological receptors since the previous FYR
Since the 2015 FYR the following changes have occurred in recommended exposure pathway
considerations:
• 2014 OSWER Directive on the Update of Standard Default Exposure Factors
In 2014, EPA finalized a Directive to update standard default exposure factors and frequently asked
questions associated with these updates (https://www.epa.gov/sites/production/files/2015-
11/documents/oswer directive 9200.1-120 exposurefactors correeted2.tJdft. Many of these exposure
factors differ from those used in the risk assessment supporting the ROD. These changes in general
would result in a slight decrease of the risk estimates for most chemicals. (Reference: EPA. 2014.
20
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Human Health Evaluation Manual, Supplemental Guidance: Update of Standard Default Exposure
Factors. OSWER Directive 9200.1-120. February 6, 2014.)
* 2018 EPA Vapor Intrusion Screening Level (VISL) Calculator
In February 2018, EPA launched an online VISL 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/vaporintnision/vapor-
introsion-screening-levelcalculator.
Evaluation of Vapor Intrusion Risks at Old Southington Landfill
Vapor intrusion evaluations were performed in 2011 and again in 2014 to determine whether
groundwater contaminants migrating from the capped landfill could pose potential VI risks to occupants
in downgradient properties. The 2011 VI investigation concluded that groundwater and soil vapor
samples collected at the C&E and Radio properties did not indicate a VI risk. In 2014, a reassessment of
risks was performed due to changes in toxicity values for some of the Site COCs. Several detections of
vinyl chloride did exceed the groundwater VISL, however there were no detections resulting in
unacceptable risks for workers. The 2015 FYR recommended that long-term monitoring data continue to
be reviewed against newer vapor intrusion risk-based screening levels.
Groundwater monitoring data collected in 2019 was reviewed which showed some detections of vinyl
chloride and TCE that could result in human health risks if a VI pathway were to become complete. A
complete VI pathway is currently unlikely due to the passive vapor barriers in place at the properties of
concern; however, the VISL exceedances indicate that continued review of groundwater data is
warranted. If Site conditions were to change such that a VI pathway could become complete, further
evaluation, may be needed.
Expected Progress Towards Meeting RAOs
The 1994 implemented remedy has effectively addressed the 1994 ROD RAOs. The 2006 ROD
established the additional RAO to prevent inhalation of VOCs by occupants of
residential/commercial/industrial buildings resulting from volatilization of VOCs in groundwater, in
excess of 1CT4 to 10"6 excess cancer risk, a hazard index >1 and/or to comply with applicable or relevant
and appropriate volatilization criteria.
In general, the Site has been in compliance with ARARs. The 2006 ROD included the 2006 CT RSRs
proposed GWVC, which were rescinded in 2013. The landfill cap has reduced the release of
contaminants from the landfill to groundwater, surface water, sediments, and air. Comparison of recent
groundwater and soil vapor analytical data to current VISLs suggests that the vapor intrusion pathway
may remain a potential concern, and continued monitoring is warranted. Implementation of the cap
remedy has effectively addressed its 1994 RAOs, implementations of ICs has effectively met the 2006
vapor intrusion remedy RAOs, and thus in September 2018 the Site was deleted from the NPL.
21
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QUESTION C: Has any other information come to light that could call into question the
protectiveness of the remedy?
No other information has come to light that could call into question the protectiveness of the remedy.
VI. ISSUES/RECOMMENDATIONS
()i. (s) willioul IsMii's/Kccomnu'iulitlions Identified in the !-'i\?-Y(*;ir Review:
OU1 and OU2 are without issues and recommendations.
OTHER FINDINGS
In addition, the following activities were identified during the FYR that may improve health and safety,
improve management of O&M, and reduce monitoring cost, but does not affect current and/or future
protectiveness:
• Include PFAS in a future groundwater monitoring event.
• 1,4 Dioxane should be resampled and results compared to current toxicity values.
• Evaluate nature of and need for mitigation of an approximately 10-foot diameter area with minor
subsidence, likely due to landfill settlement that was observed in the southern portion of the
landfill, approximately 45 feet east of GV-2.
• Remove overgrown vegetation encroaching onto perimeter fence along western and southern
perimeters which needs to be trimmed back or removed. The plants, if'unchecked, could damage
the support rods or steel mesh fabric and compromise the fence integrity.
• Fix damage to the fencepost that was observed opposite the entrance to C&E's property.
• Clean out Black Pond drainage swale that is backed up with ponded water at the culvert inlet.
Runoff drains into this ponded area. Remove accumulated vegetative matter that is limiting
drainage into the culvert. The outlet on the western side of culvert also needs to be cleared to
improve drainage and prevent ponded water from entering into the capped materials, which could
lead to the leaching of contaminants.
• South drainage swale needs to be cleared of brush.
• Clear brush inside fence at GV1 and GVO.
• Clear brush around G304A, G303A, G302A.
22
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• Clear brush around perimeter fence and monitoring wells off-site.
VII. PROTECTIVENESS STATEMENT
Protectiveness Statements)
Operable Unit:OU I
Protectiveness Determination:
Planned Addendum
Protective
Completion Date:
Click here to ent s
Protectiveness Statement:
The OU1 remedy is protective of human health and the environment. All known exposure
pathways that could result in unacceptable risks have been addressed by permanently relocating
all homes and businesses from the landfill, capping the site effectively preventing dermal
contact with the landfill contaminants, and implementation of ICs that prevent digging through
the cap. The components of the OU1 remedy are functioning appropriately. The long-term
protectiveness of the remedial action at the Site will continue to be verified through the long-
term monitoring and performance of FYRs.
Protectiveness Statement(s)
Operable Umt:OU 2
Protectiveness Determination:
Planned Addendum
Protective
Completion Date:
Click lie
Protectiveness Statement:
The OU2 remedy is protective. CT DEEP has reclassified the groundwater impacted by the
plume to a GB (non-potable) aquifer, the community is connected to municipal water, the Town
has issued an ordinance preventing drinking water well installation, and ICs were implemented
at two downgradient properties (C&E and Radio Station) to prevent exposure to potential vapor
intrusion via groundwater thus eliminating the potential for groundwater ingestion, dermal risk,
or vapor inhalation. Monitoring will continue at certain parcels to ensure long-term
protectiveness should land use conditions change in the future.
Protectiveness Determination: Flamed Addendum
Protective Completion Date:
Clic a enter a date
Protectiveness Statement:
The remedy at the Old Southington Landfill Site is protective of human health and the
environment because all known exposure pathways that could result in unacceptable risks have
been addressed. The landfill cap effectively prevents dermal contact with landfill contaminants,
on-site residents and businesses were relocated from the landfill, groundwater was reclassified
by the state to non-potable, the Town issued and ordinance preventing drinking water well
23
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installation, and the community is connected to municipal water thereby eliminating the
potential for groundwater ingestion, dermal contact, and vapor inhalation. All necessary
Institutional Controls are in place and remain effective. Site-wide long-term monitoring and
FYRs continue.
VIII. NEXT REVIEW
The next five-year review report for the Old Southington Landfill Superfond Sir i •, required five years
from the completion date of this review.
24
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APPENDIX A
FIGURES
-------
quinNj
KTAlriA
500
500 1000 1500
SCALE IN FEET (APPROX.)
MAP REFERENCE:
PORTION OF 7.5 MINUTE SERIES MAP FOR
THE SOUTHINGTON, CT QUADRANGLE DATED
1968 PHOTOREVISED 1992, N.G.V.D.1929,
TAKEN FROM TOPO! CD. VERSION 1.2.4
©1998 WILDFLOWER PRODUCTIONS.
I
OLD SOUTHINGTON LANDFILL
SUPERFUND SITE
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CT
SITE LOCATION MAP
Comm.No.
61SL702
FIGURE 1
Mi
-------
G303A.B.C
mm*
CHUCK + EDDY'S
rv\ mll'f ®?' I If h 's~-~—
\WW'- ,
,i , \\ j \ \ \ \ / // ,
; i/\ l\v il '1
¦>, ' \ L\\
ra /
LEGEND
o GAS VENTS
• GAS MONITORING PROBES
MONITORING WELLS
W CHAIN LINK FENCE
NORTH PORTION
x\\ jjrjf ****, ;']-8 •-
> \ \\\
I ° •
^ -s; _o\
\\ v ,<%
-A \
SN\V>
(jjyi-'
v
CAPPED LANDFILL
BOUNDARY
v
SOUTH PORTION
GRAPHIC SCALE
100' 200'
400'
Nobis Engineering, Inc.
5B5 Middlesex St.
Lowell, MA Q185E
Tel (978) 683-0891
Fax (978) 683-0966
www.nobisengineering.com
FIGURE 2
DETAILED SITE MAP
WITH PREVIOUS ON-SITE BUILDING LOCATIONS
OLD SOUTINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
DRAWN BY:
ML
PROJECT: 80046.06
APPROVED BY:
JM
JULY 2010
-------
Old Southington Landfill Superfund
Site: Gas BarrierTrench Location Map
Figure 3
BM SO
NAIL IN SNET#28
ELEVATION 49.3<
: DATUM—NGVO
1535
GAS BARRIER TRENCH
NORTHERN
PORTION
OF LANDFILL
3-FOOT UGH
16-FOOT WIDE DOUGLE
LEAF VEHICLE ACCESS GATE
6-FOOT HIGH
16-FOOT WIDE DOUBLE
LEAF VEHICLE ACCESS GATE
BLACKPOND
J RE ACE DRAIN PIPE
DAYL
34iTS IN BLACK POND
LARGE SWALE RIPRAP.
LEGEND:
Historical Limits of Black Pond
* *- Existing Security Fence
Limit of Landfill
-------
QM57 ^dw-3^
^63^uTU7Z
M64CJ 0^00117
DM67 O
M69 0
G309A
GZ-5S
SCALS IN FEET
LEGEND:
EXISTING/PREVIOUS SAMPLING POINTS
G304A Q MICROWELL POINTS - SEPTEMBER 2004
SDW—1 O SMALL DIAMETER MONITORING WELLS
M19 - 25 O MICROWELL POINTS - SEPTEMBER 2004
EXISTING/PREVIOUS SAMPLING POINTS EXCEEDING RESID. VOL RSRs
EXISTING/PREVIOUS SAMPLING POINTS EXCEEDING COMM. VOL. RSRs
CURRENT SAMPLING POINTS - OCTOBER/NOVEMBER 2005
PZ—1 O PIEZOMETER (does not exceed CT RSRs resid. volatilization)
M26 — 77 O MICROWELL POINTS (does not exceed CT RSRs resid. volatilization)
MICROWELL/PIEZOMETER POINTS EXCEEDING RESIDENTIAL VOLAT. RSRs
MICROWELL POINTS EXCEEDING COMMERCIAL VOLAT. RSRs
EXTENT OF STUDY SITE
l#C KLEINFELDER
Employee-owned
30 Porter Road • Littleton, MA 01460 • (978) 486-0060
32 Daniel Webster Highway
Suite 25
Merrimack, NH 03054
(003) 889-3737
OLD SOUTHINGT0N LANDFILL
SUPERFUND SITE
FIGURE 4
CT RSRs PROPOSED VOLATILIZATION
CRITERIA ASSESSMENT I
GSC REF.: 060201.02RSRS
CHECKED BY: I
DRAFTED BY: WGW
DATE: 5/30/06 !
REVISED BY: ANG
DATE: 7/27/06
SOURCE:
-------
65
AC
f/
[
8 |
k>
to
to
66
-
.96 AC
8
o
208.00
[5> S
157 00
SANITARY SEWER ESMT
Legend
Capped Landfill Boundary
Property Owner
TOWN Town of Southington
CTDEEP Connecticut Department of Energy and Environmental Protection
Notes:
1. Cap extent (in red) from LEA.
2. Property lines from Town of Southington Geographic and Property Information Network, 2017.
3. Locations of site features depicted hereon are approximate and given for illustrative purposes only.
50
100
200
Feet
1 inch = 80 feet
Engineering a Sustainable Future
Nobis Engineering, Inc.
585 Middlesex Street
Lowell, MA 01851
(978) 683-0891
"www.nobiseng.com
Client-Focused, Employee-Owned
FIGURES
SITE PLAN AND PARCELS
OLD SOUTHINGTON LANDFILL
OLD TURNPIKE ROAD
SOUTHINGTON, CONNECTICUT
PREPARED BY: JH
PROJECT NO. 80056
CHECKED BY: LC
DATE: FEBRUARY 2018
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APPENDIX B
SITE HISTORY CHRONOLOGY
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APPENDIX H - SITE HISTORY CHRONOLOGY
Event
Date
Old Turnpike Landfill accepts mixed residential,
commercial, and industrial waste.
1920-1967
Town of Southington closes Old Turnpike Landfill.
1967
CT Dept. of Public Health (CT DPH) initiates groundwater
sampling at the Site.
1978
CT DPH closes municipal groundwater Production Well #5.
1979
EPA initiates hydrogeologic investigations at the landfill.
1980
Old Southington Landfill Site placed on the NPL
1984
Administrative Order by Consent issued by EPA
1987
Remedial Investigation/Feasibility Study (RI/FS) Report and
Risk Assessment (RA) completed.
1993
EPA issued Addendum to RI/FS Report
1994
Record of Decision (ROD) for Interim Remedial Action for
1994
Limited Source Control issued by EPA.
Consent Decree between EPA and Performing Settling
Defendants (PSDs) lodged.
1998
Supplemental Groundwater Investigation initiated.
1999
100 % Remedial Design Report for landfill cap completed.
2000
Landfill Cap Construction initiated.
2000
Long-Term Groundwater Monitoring Program initiated.
2000
Landfill Cap Construction completed.
2001
Landfill Operation & Maintenance (O&M) Program
initiated.
2001 (ongoing)
Combustible Gas Comprehensive Summary Report
completed.
2003, 2004, 2006
Supplemental Hydrogeologic Review completed.
2005
1st FYR Site Inspection by EPA, CT DEEP, Nobis, and
PSDs.
2005
1st FYR completed.
September 2005
Supplemental RI Report for groundwater completed.
2006
Risk Assessment for Gas Vent VOCs completed.
2006
Amended FS completed.
2006
Landfill Inspection Cap Effectiveness Monitoring
2001 (ongoing)
Final ROD
2006
Gas Vent Monitoring
2001 (ongoing)
Radio Station Vapor Intrusion (VI) Assessment completed.
2006
Second Consent Decree signed between EPA, CT DEEP,
2009
and PSDs.
Gas Collection Verification Study completed.
2009
Fish Study of Black Pond conducted.
2009
-------
Vertical landfill gas barrier installed
2009
Restoration and Landscaping of Northern Portion of Landfill
2010
completed due to gas barrier installation.
2nd FYR Site Inspection by EPA, Nobis, and PSDs.
2010
2nd FYR completed
September 2010
GA/GB Groundwater Boundary Study completed.
2012
Vapor Intrusion Monitoring Plan (VIMP) and Vapor
Intrusion Groundwater Investigation completed.
2014
3rd FYR Site Inspection by EPA, CT DEEP, Nobis, and
2015
PSDs.
3rd FYR completed
September 2015
Long-Term Monitoring
ongoing
O&M
ongoing
Final Close Out Report (FCOR) completed
May 2018
OU2 Remedial Action Completion Report (RACR)
completed
June 2018
Site Deleted from NPL
September 2018
4th FYR completed
September 2020
-------
APPENDIX C
TABLES
-------
Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Southington Landfill Superfund Site
Southington, Connecticut
February 2020
page 1 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD (%)
Statistic
Result
Kendall's Tau (T) Result
Trend Conclusion
S
T
CF
p-value
G302A
benzene
10
9
90
-8
-0.2
72.9
0.271
Stable
G302A
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G302A
cis-1,2-dichloroethene
10
1
10
9
0.2
75.8
0.242
No Change
G302A
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G302A
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G302A
TCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G302A
Vinyl chloride
10
9
90
-13
-0.3
85.4
0.146
No Change
G302A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G303A
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G303A
cis-1,2-dichloroethene
10
1
10
-5
-0.1
63.6
0.364
Stable
G303A
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
TCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
Vinyl chloride
10
9
90
-3
-0.1
56.9
0.431
No Change
G303A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
-------
Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Southington Landfill Superfund Site
Southington, Connecticut
February 2020
page 2 of 5
Total No. of
No. of
Statistic
Kendall's Tau (T) Result
Well ID
Analyte
Analyses
Detections
FOD (%)
Result
Trend Conclusion
S
T
CF
p-value
G304A
1,1-DCA
10
5
50
-14
-0.3
87.3
0.127
Stable
G304A
1,2-DCA
10
4
40
7
0.2
70.0
0.300
No Change
G304A
Acetone
10
5
50
8
0.2
72.9
0.271
No Change
G304A
benzene
10
6
60
9
0.2
75.8
0.242
No Change
G304A
chloroethane
10
2
20
7
0.2
70.0
0.300
No Change
G304A
cis-1,2-dichloroethene
10
10
100
5
0.1
63.6
0.364
No Change
G304A
ethylbenzene
10
10
100
-32
-0.7
99.9
0.001
*
Decreasing
G304A
MIBK
10
10
100
-5
-0.1
63.6
0.364
Stable
G304A
PCE
10
6
60
18
0.4
93.4
0.066
Prob. Increasing
G304A
TCE
10
7
70
12
0.3
83.2
0.168
No Change
G304A
Tetrahydrofuran
10
6
60
5
0.1
63.6
0.364
No Change
G304A
Toluene
10
10
100
5
0.1
63.6
0.364
No Change
G304A
trans-1,2-DCE
11
6
54.5455
-7
-0.1
67.6
0.324
No Change
G304A
Vinyl chloride
10
10
100
27
0.6
99.2
0.008
*
Increasing
G304A
xylene
10
10
100
-23
-0.5
97.7
0.023
*
Decreasing
G304B
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304B
chloroethane
10
5
50
19
0.4
94.6
0.054
Prob. Increasing
G304B
cis-1,2-dichloroethene
10
8
80
16
0.4
90.7
0.093
Prob. Increasing
G304B
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304B
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G304B
TCE
10
1
10
7
0.2
70
0.300
No Change
G304B
Tetrahydrofuran
10
3
30
-16
-0.4
90.7
0.093
Prob. Decreasing
G304B
Vinyl chloride
10
8
80
18
0.4
93.4
0.066
Prob. Increasing
G304B
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
-------
Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Southington Landfill Superfund Site
Southington, Connecticut
February 2020
page 3 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD (%)
Statistic
Result
Kendall's Tau (T) Result
Trend Conclusion
S
T
CF
p-value
G304C
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G304C
cis-1,2-dichloroethene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
TCE
10
10
100
-10
-0.2
78.4
0.216
Stable
G304C
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G311A
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G311A
cis-1,2-dichloroethene
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
TCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G312A
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G312A
cis-1,2-dichloroethene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
TCE
10
5
50
5
0.1
63.6
0.364
No Change
G312A
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
-------
Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Southington Landfill Superfund Site
Southington, Connecticut
February 2020
page 4 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD (%)
Statistic
Result
Kendall's Tau (T) Result
Trend Conclusion
S
T
CF
p-value
G312B
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312B
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G312B
cis-1,2-dichloroethene
10
7
70
8
0.2
72.9
0.271
No Change
G312B
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312B
PCE
10
10
100
21
0.5
96.4
0.036
*
Increasing
G312B
TCE
10
5
50
19
0.4
84.6
0.154
Prob. Increasing
G312B
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
G312B
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G312C
benzene
10
10
100
17
0.4
92.2
0.078
Prob. Increasing
G312C
chloroethane
10
8
80
-20
-0.4
95.5
0.045
*
Decreasing
G312C
cis-1,2-dichloroethene
10
10
100
17
0.4
92.2
0.078
Prob. Increasing
G312C
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312C
PCE
10
8
80
13
0.3
85.4
0.146
No Change
G312C
TCE
10
8
80
15
0.3
89.2
0.108
No Change
G312C
Vinyl chloride
10
5
50
17
0.4
92.2
0.078
Prob. Increasing
G312C
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G313A
benzene
10
1
10
3
0.1
56.9
0.431
No Change
G313A
chloroethane
10
1
10
9
0.2
75.8
0.242
No Change
G313A
cis-1,2-dichloroethene
10
1
10
9
0.2
75.8
0.242
No Change
G313A
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G313A
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G313A
TCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G313A
Vinyl chloride
10
4
40
16
0.4
90.7
0.093
Prob. Increasing
G313A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
-------
Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Southington Landfill Superfund Site
Southington, Connecticut
February 2020
page 5 of 5
Total No. of
No. of
Statistic
Kendall's Tau (T) Result
Well ID
Analyte
Analyses
Detections
FOD (%)
Result
Trend Conclusion
S
T
CF
p-value
GZ-5M
benzene
10
4
40
23
0.5
97.7
0.023
*
Increasing
GZ-5M
chloroethane
10
10
100
-33
-0.7
99.9
0.001
*
Decreasing
GZ-5M
cis-1,2-dichloroethene
10
10
100
-18
-0.4
93.4
0.066
Prob. Decreasing
GZ-5M
ethylbenzene
10
0
0
9
0.2
75.8
0.242
(No detects)
GZ-5M
PCE
10
9
90
9
0.2
75.8
0.242
No Change
GZ-5M
TCE
10
10
100
-14
-0.3
87.3
0.127
Stable
GZ-5M
trans-1,2-DCE
10
5
50
-7
-0.2
70.7
0.293
No Change
GZ-5M
Vinyl chloride
10
10
100
-6
-0.1
66.8
0.332
Stable
GZ-5M
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
GZ-5S
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
GZ-5S
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
GZ-5S
cis-1,2-dichloroethene
10
10
100
-4
-0.1
60.3
0.397
Stable
GZ-5S
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
GZ-5S
PCE
10
1
10
9
0.2
75.8
0.242
No Change
GZ-5S
TCE
10
9
90
0.17
0.0
92.2
0.078
Prob. Decreasing
GZ-5S
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
GZ-5S
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Abbreviations:
CF - Correlation factor
FOD - Frequency of Detection
S - Kendall test statistic
X - Kendall's tau correlation coeffcient
Nobis Engineering, Inc.
-------
Table 2
Significant Concentration Changes by Well
Old Southington Landfill Superfund Site
February 2020
CHEMICAL
WELLS WITH SIGNIFICANT
INCREASE
WELLS WITH SIGNIFICANT
DECREASE
Chloroethane
G312C, GZ-5M
Vinyl chloride
G304A
Tetrachloroethene (PCE)
G312B
Benzene
GZ-5M
Ethylbenzene
G304A
Xylene
G304A
Note: Based on Mann-Kendall trends analysis for semi-annual groundwater sampling performed between
2015 to 2019.
Nobis Engineering, Inc.
-------
Table 3. Regional Kendall Test (S) - Summary of Grouped Well Results
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Shallow Monitoring Well ID
Analyte
Total # of
Analyses
# of
Detections
FOD (%)
Statistic
S) Result
Trend Conclusion*
S
p-value
1,1-Dichloroethane
80
26
32.5%
-9.0
0.2399
No change
1,2-Dichloroethane
80
7
8.8%
-1.0
1.000
No change
Acetone
80
9
11.3%
-3.0
0.6134
No change
Benzene
80
27
33.8%
-1.0
1.000
No change
Chloroethane
80
4
5.0%
0.0
1.000
No change
cis-1,2-DCE
80
33
41.3%
10.0
0.2346
No change
Ethylbenzene
80
20
25.0%
-6.0
0.2207
No change
MIBK
80
20
25.0%
2.0
0.8065
No change
Tetrachloroethylene (PCE)
80
11
13.8%
-7.0
0.2174
No change
Tetrahydrofuran
80
12
15.0%
9.0
0.1551
No change
Toluene
80
20
25.0%
4.0
0.4624
No change
trans-1,2-DCE
80
12
15.0%
-5.0
0.4470
No change
Trichloroethylene (TCE)
80
23
28.8%
-5.0
0.5677
No change
Vinyl Chloride
80
42
52.5%
11.0
0.2172
No change
Xylenes, total
80
20
25.0%
-6.0
0.2207
No change
Intermediate Monitoring Well ID
Analyte
Total # of
Analyses
# of
Detections
FOD (%)
Statistic
S) Result
Trend Conclusion*
S
p-value
1,1-Dichloroethane
39
5
13%
-5.0
0.312
No change
1,2-Dichloroethane
39
0
0%
-
-
(No detects)
Acetone
39
0
0%
-
-
(No detects)
Benzene
39
8
21%
7.0
0.1296
No change
Chloroethane
39
24
62%
-2.0
0.8582
No change
cis-1,2-DCE
39
30
77%
1.0
1.000
No change
Ethylbenzene
39
0
0%
-
-
(No detects)
MIBK
39
0
0%
-
-
(No detects)
Tetrachloroethylene (PCE)
39
25
64%
8.0
0.2253
No change
Tetrahydrofuran
39
4
10%
-5.0
0.3122
No change
Toluene
39
0
0%
-
-
(No detects)
trans-1,2-DCE
39
12
31%
3.0
0.7135
No change
Trichloroethylene (TCE)
39
25
64%
7.0
0.3448
No change
Vinyl Chloride
39
27
69%
2.0
0.8625
No change
Xylenes, total
39
0
0%
-
-
(No detects)
Deep Monitoring Well ID
Analyte
Total # of
Analyses
# of
Detections
FOD (%)
Statistic
S) Result
Trend Conclusion*
S
p-value
1,1-Dichloroethane
20
5
25%
7.0
0.1296
No change
1,2-Dichloroethane
20
0
0%
-
-
(No detects)
Acetone
20
0
0%
-
-
(No detects)
Benzene
20
1
5%
2.0
0.7237
No change
Chloroethane
20
8
40%
-6.0
0.2207
No change
cis-1,2-DCE
20
10
50%
6.0
0.2207
No change
Ethylbenzene
20
0
0%
-
-
(No detects)
MIBK
20
0
0%
-
-
(No detects)
Tetrachloroethylene (PCE)
20
2
10%
7.0
0.0961
No change
Tetrahydrofuran
20
0
0%
-
-
(No detects)
Toluene
20
0
0%
-
-
(No detects)
trans-1,2-DCE
20
1
5%
2.0
0.7237
No change
Trichloroethylene (TCE)
20
18
90%
-2.0
0.8625
No change
Vinyl Chloride
20
5
25%
5.0
0.3122
No change
Xylenes, total
20
0
0%
-
-
(No detects)
*A statistically significant trend is identified if p-value < 0.05
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 1 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Dale (or planned)
Landfill Cap, Soil,
and Indoor Air
Yes
Yes
Three Town-
owned parcels
in northern
area of capped
landfill:
(1) 425 Old
Turnpike
Road, Map 64,
Lot 22
(2) 435 Old
Turnpike
Road, Map 64,
Lot 23
(3) 84 Rejean
Road, Map 65,
Lot 46
In the restrictive covenant, the Town agreed to: 1)
place notice of the restriction on the deed, title, or
other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that
will disturb any of the remedial measures (except for
maintenance and repair upon prior approval by
EPA); 3) prohibit any activities that could result in
exposure to contaminants in the subsurface soils and
groundwater; 4) prohibit any future residential and
commercial development on the property; 5) prohibit
use or consumption of contaminated groundwater
underlying the property; 6) grant access to EPA,
including its contractors, and the State for the
purpose of conducting any activity related to the
CDs.
Declaration of Land
Use Restrictive
Covenant
(Environmental
Restriction)
executed by Town
of Southington, CT
on September 14,
2010
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 2 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Dale (or planned)
Landfill cap, Soil,
and Indoor Air
Yes
Yes
Nine
remaining
State-owned
parcels of the
landfill
(1)413 Old
Turnpike
Road Map 64,
Lot 21
(2) 455 Old
Turnpike
Road, Map 64,
Lot 24
(3) 101 Rejean
Road, Map 64,
Lot 20
(4) 477 Old
Turnpike
Road, Map 64,
Lot 25
In the restrictive covenant, the State agreed to: 1)
place notice of the restriction on the deed, title, or
other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that
will disturb any of the remedial measures (except for
maintenance and repair upon prior approval by
EPA); 3) prohibit any activities that could result in
exposure to contaminants in the subsurface soils and
groundwater; 4) prohibit any future residential and
commercial development on the property; 5) prohibit
use or consumption of contaminated groundwater
underlying the property; 6) grant access to EPA,
including its contractors, and the State for the
purpose of conducting any activity related to the
CDs; 7) any new structure to be constructed in
accordance to a plan approved by EPA that
minimizes the risk of inhalation of contaminants.
ELUR recorded on
September 17, 2015
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 3 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Dale (or planned)
(5) 485 Old
Turnpike
Road, Map 64,
Lot 27
(6) 503 Old
Turnpike
Road, Map 64,
Lot 29
(7) 497 Old
Turnpike
Road, Map 64,
Lot 30
(8) 597 Old
Turnpike
Road, Map 53,
Lot 127
(9) 601 Old
Turnpike
Road, Map 53,
Lot 128
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Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 4 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of l(
Instrument
Implemented and
Dale (or planned)
Indoor Air
Yes
Yes
Radio Station
Property, 440
Old Turnpike
Rd
Map 064, Lot
047
In the restrictive covenant, the property owners
agreed to: 1) restrict the construction of a building
over groundwater at the Subject Area where volatile
organic compounds concentrations exceed the RCSA
Section 22a-133k-l(75) Volatilization Criteria (unless
a release is obtained from the CT DEEP); 2) allow no
action or inaction would allow a risk of pollutant
migration, or potential hazard to human health or the
environment; or result in the disturbance of structural
integrity of engineering controls used to contain
pollutants or limit human exposure; 3) in the event of
an emergency, notify the CT DEEP, implement
measures to limit actual or potential risks to human
health and the environment, implement a plan to
ensure restoration of the property to conditions prior
to the emergency; 4) not allow alterations to the
property inconsistent with the ELUR until a release is
approved by the CT DEEP; 5) allows access to the
CT DEEP agents that perform pollution remediation
activities; 6) allow access onto the property by the
CT DEEP upon reasonable notice; 7) require the
property owner to notify any future interests of the
ELUR record on
April 19,2017
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 5 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Dale (or planned)
ELUR requirements. This ELUR is enforceable by
the CT DEEP.
Indoor Air
Yes
Yes
Chuck &
Eddie's Used
Auto Parts
Property, 450
Old Turnpike
Rd
Map 064, Lot
046
In the restrictive covenant, the property owners
agreed to: 1) restrict the construction of a building
over groundwater at the Subject Area where volatile
organic compounds concentrations exceed the RCSA
Section 22a-133k-l(75) Volatilization Criteria (unless
a release is obtained from the CT DEEP); 2) allow no
action or inaction would allow a risk of pollutant
migration, or potential hazard to human health or the
environment; or result in the disturbance of structural
integrity of engineering controls used to contain
pollutants or limit human exposure; 3) in the event of
an emergency, notify the CT DEEP, implement
measures to limit actual or potential risks to human
health and the environment, implement a plan to
ensure restoration of the property to conditions prior
to the emergency; 4) not allow alterations to the
ELUR recorded on
June 22, 2017
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 6 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Dale (or planned)
property inconsistent with the ELUR until a release is
approved by the CT DEEP; 5) allows access to the
CT DEEP agents that perform pollution remediation
activities; 6) allow access onto the property by the
CT DEEP upon reasonable notice; 7) require the
property owner to notify any future interests of the
ELUR requirements. This ELUR is enforceable by
the CT DEEP.
Landfill cap, Soil,
and Indoor Air
Yes
Yes
One Town-
owned parcel
located in the
southern area
of the capped
landfill
493 Old
Turnpike
Road, Map 63,
Lot 26
In the restrictive covenant, the Town agreed to: 1)
place notice of the restriction on the deed, title, or
other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that
will disturb any of the remedial measures (except for
maintenance and repair upon prior approval by
EPA); 3) prohibit any activities that could result in
exposure to contaminants in the subsurface soils and
groundwater; 4) prohibit any future residential and
commercial development on the property; 5) prohibit
use or consumption of contaminated groundwater
underlying the property; 6) grant access to EPA,
including its contractors, and the State for the
April 9,2018
Declaration of Land
Use Restrictive
Covenant
(Environmental
Restriction)
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 7 of 7
Media,
engineered
controls, and
areas that do not
support I l /l K
based on current
conditions
ICs
Needed
IC s C ailed
for in the
Decision
Documents
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Dale (or planned)
purpose of conducting any activity related to the
CDs.
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TABLE 5
ROLES AND RESPONSIBILITIES
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
Page 1 of 3
PARTY
AFFILIATION1
RESPONSIBILITIES
CONTROLLING DOCUMENTS
(As appropriate)
U. S. Environmental Protection Agency
Federal regulatory agency
• Oversight of OSL Site to ensure continuing effectiveness of
Records of Decision remedial objectives.
• Review long-term monitoring reports, evaluate groundwater
contaminant trends, and assess need for additional action.
• Review periodic O&M reports, and assess need for additional
action.
• Review inspection reports for compliance with ELURs.
• Prepare Five-Year Reviews to assess protectiveness and
effectiveness of ROD remedies. Assess changes and verify
response actions are performed.
• 1994 Record of Decision
• 2006 Record of Decision
• 1998 Consent Decree
• 2008 Consent Decree
Connecticut Department of Energy and
Environmental Protection
State regulatory agency
• Oversight of OSL Site to ensure continuing effectiveness of
Records of Decision remedial objectives.
• Review long-term monitoring reports, evaluate groundwater
contaminant trends, and assess need for additional action.
• Review periodic O&M reports, and assess need for additional
action.
• Review inspection reports for compliance with ELURs.
• Provide input into Five-Year Reviews.
• 1994 Record of Decision
• 2006 Record of Decision
• Sep. 17, 2015 Environmental Land Use
Restrictive Covenant for nine parcels.
Raytheon Technologies Corporation
(formerly known as United Technologies
Corporation)
Performing Settling Defendant
(OU1 and OU2)
• Responsible for Long-Term Monitoring, Operations &
Maintenance of the capped landfill, and biennial ELUR and
Vapor Barrier inspections (delegated to PSDs' contractor).
• 1998 Consent Decree
• 2008 Consent Decree
• Operations and Maintenance Plan (CRA,
2001)
• Vapor Intrusion Inspection Plan, RACR,
Appendix N, 2018
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TABLE 5
ROLES AND RESPONSIBILITIES
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
Page 2 of 3
PARTY
AFFILIATION1
RESPONSIBILITIES
CONTROLLING DOCUMENTS
(As appropriate)
Town of Southington, Connecticut
Performing Settling Defendant
(OU1 and OU2)
• Responsible for some of the Operations & Maintenance of the
capped landfill (monthly inspections of landfill components,
maintenance offence barrier, routine mowing of cap and
vegetation).
• 1998 Consent Decree
• 2008 Consent Decree
• Sep. 14, 2010 Environmental Land Use
Restrictive Covenant for three parcels at
northern part of landfill.
• Apr. 10, 2018 Environmental Land Use
Restrictive Covenant for one parcel at
southern part of landfill.
Kraft Foods Global, Inc.
Settling Defendant (OU1),
Performing Settling Defendant
(OU2)
• Responsible for Long-Term Monitoring, Operations &
Maintenance of the capped landfill, and biennial ELUR and
Vapor Barrier inspections (delegated to PSDs' contractor).
• 1998 Consent Decree
• 2008 Consent Decree
• Vapor Intrusion Inspection Plan, RACR,
Appendix N, 2018
Shell Oil Company
Settling Defendant (OU1),
Performing Settling Defendant
(OU2)
• Responsible for Long-Term Monitoring, Operations &
Maintenance of the capped landfill, and biennial ELUR and
Vapor Barrier inspections (delegated to PSDs' contractor).
• 1998 Consent Decree
• 2008 Consent Decree
• Vapor Intrusion Inspection Plan, RACR,
Appendix N, 2018
Aerojet Rocketdyne
Settling Defendant (OU1),
Performing Settling Defendant
(OU2)
• Responsible for Long-Term Monitoring, Operations &
Maintenance of the capped landfill, and biennial ELUR and
Vapor Barrier inspections (delegated to PSDs' contractor).
• 1998 Consent Decree
• 2008 Consent Decree
• Vapor Intrusion Inspection Plan, RACR,
Appendix N, 2018
Loureiro Engineering Associates, Inc.
Contractor to PSDs
• Implement, document, and report the performance of Long-
Term Monitoring, Operations & Maintenance, and biennial
ELUR and Vapor Barrier inspections.
• Operations and Maintenance Plan (CRA,
2001)
• Vapor Intrusion Inspection Plan, RACR,
Appendix N, 2018
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TABLE 5
ROLES AND RESPONSIBILITIES
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
Page 3 of 3
PARTY
AFFILIATION1
RESPONSIBILITIES
CONTROLLING DOCUMENTS
(As appropriate)
Charles V. Arcangelo (Chuck & Eddie's
Property)
Owner of 450 Old Turnpike Road,
Southington, CT
• Adherence to ELUR requirements for property.
• June 22, 2017 Declaration of Environmental
Land Use Restriction and Grant of Easement
for one parcel.
DGS Holdings, LLC; NES Realty, LLC;
Trustees of Stevens Family Trust; and
U.D.T (Radio Station Property)
Owners of 440 Old Turnpike Road
Southington, CT
• Adherence to ELUR requirements for property.
• April 19, 2017 Environmental Land Use
Restriction and Grant of Easement for one
parcel.
Note 1: The Performing Settling Defendants (PSDs) is a subset of the Settling Defendants (SDs). While the SDs are financially liable for the remedial actions associated with Operable Unit 1 or 2, the
PSDs implement the Operations and Maintenance, Long-term Monitoring, and periodic inspections of the ELURs and Vapor Barrier, and provide input into the Five-Year Reviews.
Abbreviations: ELUR - Environmental Land Use Restrictions; NPL- National Priorities List; OSL- Old Southington Landfill Superfund Site; OU - Operable Unit; RACR - Remedial Action Completion
Report (LEA, 2018)
-------
APPENDIX D
SUMMARY OF INSTITUTIONAL CONTROLS
-------
Summary of Implemented Institutional Controls (ICs) at the Old Southington Landfill Site
The ICs present at the Site are summarized below and in Table 4.
The September 14, 2010 Declaration of Land Use Restrictive Covenant (Environmental
Restriction) was executed by the Town of Southington for the three Town-owned parcels located
in the northern area of the capped landfill. In the restrictive covenant, the Town agreed to: 1) place
notice of the restriction on the deed, title, or other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that will disturb any of the remedial measures
(except for maintenance and repair upon prior approval by EPA); 3) prohibit any activities that
could result in exposure to contaminants in the subsurface soils and groundwater; 4) prohibit any
future residential and commercial development on the property; 5) prohibit use or consumption of
contaminated groundwater underlying the property; 6) grant access to EPA, including its
contractors, and the State for the purpose of conducting any activity related to the Consent Decrees.
Finally, EPA, the State and/or the PSDs have the right to enforce the restrictions. The April 9,
2018 Declaration of Land Use Restrictive Covenant (Environmental Restriction) was implemented
for one Town-owned parcel located in the southern area of the capped landfill, which has the same
restrictions as the September 2010 restrictive covenant.
The September 17, 2015 Declarations of Environmental Land Use Restrictive Covenant was
implemented by the CT DEEP for the remaining nine state-owned parcels of the landfill. This
Covenant has the same six restrictions as described in the September 2010 Covenant, and one
restriction that requires any new structure to be constructed in accordance to a plan approved by
EPA that minimizes the risk of inhalation of contaminants. In addition, this Covenant indicates
EPA and/or the PSDs have the right to enforce the restrictions.
The April 19, 2017 Declaration of Environmental Land Use Restriction (ELUR) was recorded by
the owners of the Radio Station Property. In this ELUR, the owners agreed to: 1) restrict the
construction of a building over groundwater at the Subject Area where volatile organic compounds
concentrations exceed the RCSA Section 22a-133k-l(75) Volatilization Criteria (unless a release
-------
is obtained from the CT DEEP); 2) allow no action or inaction would allow a risk of pollutant
migration, or potential hazard to human health or the environment; or result in the disturbance of
structural integrity of engineering controls used to contain pollutants or limit human exposure; 3)
in the event of an emergency, notify the CT DEEP, implement measures to limit actual or potential
risks to human health and the environment, implement a plan to ensure restoration of the property
to conditions prior to the emergency; 4) not allow alterations to the property inconsistent with the
ELUR until a release is approved by the CT DEEP; 5) allows access to the CT DEEP agents that
perform pollution remediation activities; 6) allow access onto the property by the CT DEEP upon
reasonable notice; 7) require the property owner to notify any future interests of the ELUR
requirements. This ELUR is enforceable by the CT DEEP.
The June 22, 2017 Declaration of ELUR was recorded by the owner of the property where the
C&E's Used Auto Parts business is located. This ELUR has the same seven restrictions as
described in the April 2017 ELUR.
The April 9, 2018 Declaration of Land Use Restrictive Covenant (Environmental Restriction) was
implemented for one Town-owned parcel located in the southern area of the capped landfill, which
has the same restrictions as the September 2010 restrictive covenant.
The April 9, 2018 Declaration of Land Use Restrictive Covenant (Environmental Restriction) was
implemented for one Town-owned parcel located in the southern area of the capped landfill, which
has the same restrictions as the September 2010 restrictive covenant.
-------
APPENDIX E
LOG OF INTERVIEWS
-------
INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Third Five-Year Review (2020)
Time: 1:15 pm Date: Aug 3, 2020
Type: ~ Telephone ~ Visit E Email
Location of Interview:
~ Incoming S Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Stephen J. Gaura
Title:
Environmental
Analyst 2
Organization: CT DEEP
Remediation Division
Bureau of Water Protection and Land
Reuse
Telephone No: : 860.424.3786
Fax No: 860.425.4057
E-Mail Address: steve. gaura@ct. gov
Street Address:
79 Elm Street, Hartford, CT 06106
Summary o
Conversation
Ql. What is your overall Impression of project and Site?
Al. The project is under very good oversight from EPA, Site Manager Almerinda Silva, and
the consultants. The Site has a long and complex history of investigation and remediation, but
overall is in good shape based on the ongoing monitoring data and appearance. From looking
at it, one would not think the Site is a Superfund Site, nor a landfill.
Q2. What effects have Site operations had on the surrounding community?
A2. I have not heard of any negative impacts.
Q3. Are you aware of any community concerns regarding the Site of its operation and
administration?
A3. No. To the best of my knowledge, there are no community concerns regarding the Site of
Page lof2
-------
its operation and administration.
Q4. Is the remedy functioning as expected?
A4. Generally, yes.
Q5. Has there been any significant changes in the O & M activities or a chance to
optimize the O & M?
A5. I understand there was a methane barrier trench installed in 2009-2012, otherwise I am
unaware of any other physical changes. The Performing Settling Defendants (PSDs) which
includes the Town of Southington are responsible for the O&M at the Site. Some occasional
overgrown vegetation and garbage from the street has been observed along the landfill fence
line and some overgrown vegetation has been observed in two swale areas on the landfill. This
work is addressed by the PSDs. Thus, there has been no significant changes in the O&M
activities necessitating changes to the O&M plan.
Q6. Do you feel information related to the Site is readily available?
A6. Yes.
Q7. Are you aware of any events, incidents, or activities at the Site such as vandalism,
trespassing or emergency response from local authorities?
A7. No.
Q8. Do you have any comments, suggestions, or recommendations regarding the Site's
management or operation?
A8. Good work.
Page 2of2
-------
INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Third Five-Year Review (2015)
Time: 3:00 pm
Date: July 29,
2020
Type: E Telephone ~ Visit ~ Email
Location of Interview:
~ Incoming S Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Mark J. Sciota
Title:
Town Manager
Organization:
Town of Southington
Telephone No: : 860.276.6200
Fax No: 860.628.4727
E-Mail Address: sciotam@southington.org
Street Address: Town Hall
75 Main Street, Southington, CT 06489
Summary of Conversation
Ql. What is your overall Impression of project and Site?
Al. I have noticed an increase in frequency of people using the northern passive recreational
area to walk their dogs and enjoy the view of Black Pond. This may have been due to the
deleting the Site from the National Priorities List (NPL).
Q2. What effects have the more recent Site operations had on the surrounding
community?
A2. The only times we ever get complaints which has nothing to do with the operation of the
Site itself, is some vegetation and in particular garbage from outside sources that collects along
the fence line which is unsightly and has to be picked up quite often. But the design is working
as anticipated.
Q3. Are you aware of any community concerns regarding the Site of its operation and
administration?
A3. No just the opposite. It's being used for passive recreation.
Q4. Is the remedy functioning as expected?
A4. I know that there is still regular testing there and there has been no red flags so it is still
Page 1 of 2
-------
operating as anticipated.
Q5. Has there been any significant changes in the O & M activities or a chance to
optimize the O & M?
A5. No, we've had preliminary discussions about possibly installing a solar farm there, but we
would have to get all appropriate parties onboard and this is still in its infancy stage at this
point.
Q6. Do you feel information related to the Site is readily available?
A6. Well, it is so extensive that I am not sure everyone has time to do it but, yes it is readily
available.
Q7. Are you aware of any events, incidents, or activities at the Site such as vandalism,
trespassing or emergency response from local authorities?
A7. No there is really nothing there and there has never been a traffic nuisance, so the answer
is no.
Q8. Do you have any comments, suggestions, or recommendations regarding the Site's
management or operation?
A8. No, my suggestion would be that eventually all the parties including the Town would
need to work together to consider passive solar farm at the Site but as I said before, it is still in
very early infancy stage and currently on the back burner.
Page 2 of 2
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INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Fourth Five-Year Review (2020)
Time: 1:30 pm
Date: August 17,
2020
Type: ~ Telephone ~ Visit El Email
Location of Interview:
~ Incoming El Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Joseph T. Trzaski, L.E.P.
Title:
Senior Project
Scientist
Organization: Loureiro Engineering
Associates, Inc.
Telephone No: : 860.410.2942
Fax No: 860.747.8822
E-Mail Address: ittrzaski@loureiro.com
Street Address: 100 Northwest Drive, Plainville, CT
06062
Summary oi
' Conversation
01: What is your overall impression of the project and site?
Al: A Remedial Action Completion Report (RACR) was submitted to the United States
Environmental Protection Agency (EPA) and the Connecticut Department of Energy and
Environmental Protection (DEEP) on June 22, 2018. The Site was delisted from the National
Priorities List (NPL) on September 12, 2018.
Both the remedy for 1994 Record of Decision (ROD) and respective Consent Decree (CD) and
the 2006 ROD and respective CD remain protective of human health and the environment. The
long-term protectiveness of the remedial action at the Site for OU1 (1994 ROD) and OU2 (2006
ROD) will continue to be verified through the monitoring programs (i.e., cap effectiveness
groundwater monitoring, inspections of the landfill completed by the Town of Southington and
Loureiro Engineering Associates, Inc. (LEA), inspections of the ELURs, and Five Year Reviews
[FYRs]).
02: Is the remedy functioning as expected? How well is the remedy performing?
A2: The landfill cap completed in 2001 as part of operable unit 1 (OU1, 1994 ROD) continues to
function as designed. The cap continues to prevent dermal exposure to contaminants and minimize
infiltration of precipitation that could further mobilize contaminants. There have been no issues
Page 1 of 5
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related to the cap with the exception of occasional minor corrective actions identified during
monthly inspections of the landfill completed by the Town of Southington. One corrective action
included the replacement of perimeter fence at the entrance to the Loureiro Contractors, Inc. (LCI)
Yard following a car accident that damaged the fence in February 2019.
As part of OU2 (2006 ROD), institutional controls (ICs) in the form of environmental land use
restrictions (ELUR) were recorded on the land record of the Town of Southington in 2017 for two
properties downgradient of the landfill: 440 Old Turnpike Road (Radio Station) and 450 Old
Turnpike Road (Chuck & Eddies). The ELUR for 440 Old Turnpike Road was filed on May 3,
2017 and the ELUR for 450 Old Turnpike Road was filed on June 29, 2017. These two ELURs
prohibit the construction of new buildings at the offsite properties without the inclusion of a vapor
barrier or other vapor mitigation system.
The PSDs have begun the implementation of an institutional control monitoring program to ensure
that the ELURs are maintained, monitored, and appropriately enforced, where necessary, on all
relevant portions of the Site. Biennial inspections of the ELURs began in September 2019. The
inspection completed by LEA confirmed that no new buildings have been constructed at 440 Old
Turnpike Road (Radio Station) and 450 Old Turnpike Road (Chuck & Eddies). In addition, the
Quonset hut building on the Chuck &Eddies property was also inspected to ensure that the
vapor barrier installed beneath that building remains in place and has not been compromised,
and that the sealing completed at the bases and bolts of the existing vehicle lifts remains intact.
LEA found that the caulk sealing at the baseplates and bolts of the vehicle lifts were in good
condition.
Q3: What does the monitoring data show? Are there any trends that show contaminant levels are
decreasing?
A3: Over the last decade of groundwater monitoring, wells within the heart of the plume
(e.g. G304A and GZ-5M) have fluctuated over time but overall have been demonstrated to be
stable. Increased ratios of daughter products (e.g. cis-l,2-dichloroethylene [cDCE] and vinyl
chloride) to parent products (e.g. trichloroethylene [TCE]) over time indicate that biodegradation is
occurring. Monitoring wells outside the heart of the plume continue to have stable or decreasing
VOC concentrations and in general, remain in the low part per billion concentration range.
Exceptions to this observation included increases in the concentration of 1 VOCs (as both parent
[TCE] and daughter [cDCE and vinyl chloride] products) in monitoring wells both within the
plume and along the periphery. These increases in VOC concentrations were generally observed
between the September 2017 and September 2019 sampling events. It was concluded that the
sudden rise of VOC concentrations were reflective of a notably depressed groundwater table. When
groundwater table elevations returned to within historical norms (circa 2020), so did observed VOC
concentrations. Groundwater monitoring over the past five years has generally indicated that VOCs
are generally within the range of historically detected concentrations. In addition, Mann-Kendall
analysis conducted by EPA also indicated that VOC concentrations in the intermediate and deep
portions of the aquifer are stable or declining. Therefore, it is concluded that the landfill cap
Page 2 of 5
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installed at OSL is functioning as designed. The current program of semi-annual cap-effectiveness
monitoring is appropriate to continue to monitor concentrations of VOCs in groundwater.
Corresponding to the lower groundwater elevations observed, light non-aqueous phase liquid
(LNAPL) was observed in monitoring well G304A in March 2018 at an apparent thickness of 0.18
feet, in September 2019 at an apparent thickness of 0.01 feet, and in March 2020 at an apparent
thickness of 0.02 feet. LNAPL has been sporadically detected in this monitoring well since 2002.
The containment cell of semi-solid disposal area one (SSDA-1) is gauged on a semi-annual basis
concurrently with the cap effectiveness groundwater monitoring. The water level inside SSDA-1
has fluctuated slightly over time, but pump-outs of SSDA-1 have not been warranted.
Q4: Is the remedy functioning as expected?
A4: Yes, the OU1 remedy (landfill cap) appears to be functioning as expected. In addition, the
Groundwater Remedy for OU2 has been implemented. The ELURs for the two downgradient
properties (440 Old Turnpike Road [Radio Station] and 450 Old Turnpike Road [Chuck and
Eddies]) were filed on the Town of Southington land records in 2017. The ELURs prevent the
construction of new buildings without the inclusion of a vapor barrier or other vapor mitigation
system. Long-term cap effectiveness groundwater monitoring and the institutional control
monitoring program will continue to ensure that the Groundwater Remedy is protective of human
health and the environment.
05: Is there a continuous on-site O&M presence? If so, please describe staff and activities. If
there is not a continuous on-site presence, please describe staff andfrequency of site inspections
and activities.
A5: Yes, there is a continuous on-site O&M presence. The Town of Southington has completed
monthly inspections of the landfill cap. EPA recently approved of reduction in the frequency of
landfill inspections from monthly to quarterly. The Town will complete inspections during the
months of June and December, and LEA personnel will complete the landfill inspections
concurrently with cap effectiveness monitoring conducted during the months of March and
September. Loureiro personnel are also present onsite during the semi-annual cap-effectiveness
groundwater monitoring. In addition, Loureiro completes biennial inspections of the Radio Station
and Chuck & Eddies properties to ensure that the ELURs are maintained, monitored, and
appropriately enforced. The next biennial inspection will be completed by LEA in September
2021.
06: Have there been any significant changes in the O&M requirements, maintenance schedules,
or sampling routines since start-up or in the last five years or a chance to optimize the O&M? If
so, do they affect the protectiveness or effectiveness of the remedy? Please describe changes and
impacts.
A6: EPA recently approved the reduction in the frequency of landfill inspections from monthly to
quarterly. The Town will complete inspections during the months of June and December, and LEA
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personnel will complete the landfill inspections concurrently with cap effectiveness monitoring
conducted during the months of March and September. Gauging of the fluids in SSDA-1 is
completed by LEA on a semi-annual basis during Cap Effectiveness Groundwater Monitoring.
LEA also began the completion of biennial ELUR inspections in September 2019.
In September and October 2015 Loureiro abandoned four gas probes located in the southern end of
the landfill (GP-6, GP-7, GP-9, and GP-10). As discussed in the letter prepared by Loureiro and
dated October 22, 2015, the gas probes were abandoned with bentonite grout with the nearby area
backfilled and reseeded.
Following deletion of OSL from the NPL, LEA also completed the abandonment of 27 vapor
probes along Rejean Road and Amanda Lane (to the north of the landfill) in May 2019.
Following the previous FYR in 2015, a change was made to the Cap Effectiveness Groundwater
Monitoring program. In the letter dated April 23, 2015 titled "Summary of Cap
Effectiveness and Request to Reduce Long-term Groundwater Monitoring, Old Southington
Landfill Superfund Site, Southington, Connecticut", Loureiro requested the reduction of the
sampling schedule from semi-annual to annual and the reduction in number of monitoring wells
sampled from 23 to 11. As part of the final 2015 FYR document issued by the EPA, the agency
deferred the reduction in sampling schedule but approved the reduction in number of monitoring
wells sampled. The 11 monitoring wells eliminated were: G302B, G302C, G303B, G303C, G311B,
G311C, G313C, GZ-1, GZ-3, GZ-17M, and GZ-17D. The current semi-annual groundwater
monitoring program includes the following monitoring wells: G302A, G303A, G304A/B/C,
G311 A, G312A/B/C, G313 A, and GZ-5M/S. VOCs associated with the OSL plume have only been
detected infrequently (and sporadically) at relatively low concentrations or have never been
detected in the 12 wells that have been eliminated from the monitoring program. Given the
significant volume of monitoring data that shows plume stability and the institutional controls that
are in place for the offsite properties, the reduction in the number of monitoring wells sampled does
not affect the protectiveness or effectiveness of the remedy.
07: Have there been unexpected O&M difficulties or costs at the site since start-up or in the last
five years? If so, please give details.
A7: No unexpected O&M difficulties were encountered over the last five years. The gas vents on
both the northern and southern sides of the landfill were repainted in July 2016. In the winter of
2019, the fencing along the driveway between the two sides of the landfill suffered damage from a
motor vehicle accident. The damage fencing was repaired in February 2019. Routine maintenance
has also included the clearing of brush from the Black Pond discharge swale, clearing of brush from
inside the gas vent enclosures at GV0 and GV1, clearing of brush/vegetation from the south
discharge swale, clearing of brush around monitoring wells included in the Cap Effectiveness
monitoring program, and clearing of brush around the landfill perimeter fence.
Q8: Have there been any changes in the site or surrounding property in the last 5 years, or are
changes planned?
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A8: There have been no notable changes to the site in the last 5 years. In addition, LEA also has
no knowledge of any planned changes (with the exception of ongoing maintenance and
monitoring).
With respect to surrounding properties, as mentioned above in answer A2, ELURs were recorded
on the Town of Southington land records in May and June of 2017 for 440 Old Turnpike Road
(Radio Station) and 450 Old Turnpike Road (Chuck & Eddies). These two ELURs prohibit the
construction of occupied structures without the inclusion of a vapor barrier or other vapor
mitigation system.
09: Are you aware of any changes in the state ARARs, groundwater quality standards, etc.,
since 2010?
A9: No changes to the Connecticut Remediation Standard Regulations (RSRs) have been made in
the past five years. The RSRs were revised in July 2013. The revisions did not include changes to
chemical exceedance thresholds.
Q10: Do you have any comments, suggestions, or recommendations regarding this project?
A10: The PSDs will continue with long-term cap effectiveness groundwater monitoring, quarterly
landfill inspections and O&M, and biennial institutional control monitoring program to ensure the
remedies for ROD1 and ROD2 continue to be protective of human health and the environment.
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INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Fifth Five-Year Review (2020)
Time: 1:00 pm Date: Nov 21,2019
Type: ~ Telephone E Visit ~ Other
Location of Interview:
~ Incoming ~ Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Patricia Patrick
Title:
Neighborhood
Resident
Organization:
Telephone No:
Fax No:
E-Mail Address:
Street Address:
94 RejeanRoad, Southington, CT
Summary of Conversation
Q1: What is your overall impression of the project?
A1: Everything seems fine.
Q2: Do you have any health related concerns with respect to the landfill site?
A2: No.
Q3: Do you have any general concerns with the Site?
A3: Not really a concern, more of a comment, but it seems that the swans are gone
which may be due to the growth of the weeds in the pond. Occasionally I see a man
running with his dog on the northern part of the landfill.
Q4: Is there any information that you wish to share that might be of use to EPA?
A4: No.
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INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Fifth Five-Year Review (2020)
Time: 1:10pm Date: Nov21,2019
Type: ~ Telephone E Visit ~ Other
Location of Interview:
~ Incoming ~ Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Diana Vega
Title:
Neighborhood
Resident
Organization:
Telephone No:
Fax No:
E-Mail Address:
Street Address:
88 RejeanRoad, Southington, CT
Summary of Conversation
Ql:
What is your overall impression of the project?
Al:
Everything seems fine.
Q2:
Do you have any health related concerns with respect to the landfill site?
A2:
No, but I haven't lived here long. The landfill was already capped and finished when
I moved in.
Q3:
Do you have any general concerns with the Site?
A3:
No.
Q4:
Is there any information that you wish to share that might be of use to EPA?
A4:
No.
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INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Fifth Five-Year Review (2020)
Time: 1:20 pm Date: Nov 21,2019
Type: ~ Telephone E Visit ~ Other
Location of Interview:
~ Incoming ~ Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Marcel
Title:
Friend/acquaintance of
neighborhood resident who comes
by often to do odd jobs
Organization:
Telephone No:
Fax No:
E-Mail Address:
Street Address:
67 RejeanRoad, Southington, CT
Summary of Conversation
Ql: What is your overall impression of the project?
Al: Everything seems fine.
Q2: Do you have any health related concerns with respect to the landfill site?
A2: I've seen people sometimes take their kayaks in the pond. Is that safe?
Q3: Do you have any other general concerns with the Site?
A3: No.
Q4: Is there any information that you wish to share that might be of use to EPA?
A4: Sometimes I see people on the northern part of the landfill with their dog.
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INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Fifth Five-Year Review (2020)
Time: 1:25 pm Date: Nov 21,2019
Type: ~ Telephone E Visit ~ Other
Location of Interview:
~ Incoming ~ Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Mr. Otis
Title:
Neighborhood
resident
Organization:
Telephone No:
Fax No:
E-Mail Address:
Street Address:
58 RejeanRoad, Southington, CT
Summary of Conversation
Q1: What is your overall impression of the project?
A1: Nothing major, it's just that when the leaves fall from the trees, they get trapped in
the short shrubs in front of the fence by the northern end of the landfill cap. This is unsightly and
no one seems to clean them out. Also, it seems the roots in the swale coming out of the pond are
getting tall and need to be pulled out to prevent the pond from flooding.
Q2: Do you have any health related concerns with respect to the landfill site?
A2: No.
Q3: Do you have any other general concerns with the Site?
A3: No.
Q4: Is there any information that you wish to share that might be of use to EPA?
A4: Just that those shrubs look unsightly when the leaves get caught in them and the
weeds in the pond swale need some maintenance.
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INTERVIEW RECORD
Site Name: Old Southington Landfill Superfund Site
EPA ID No.: CTD98067006
Subject: Fifth Five-Year Review (2020)
Time: 1:30pm Date: Nov21,2019
Type: ~ Telephone E Visit ~ Other
Location of Interview:
~ Incoming ~ Outgoing
Contact Made By:
Name:
Almerinda Silva
Title:
Project Manager
Organization:
EPA
Individual Contacted:
Name:
Judy Lang
Title:
Neighborhood
resident
Organization:
Telephone No:
Fax No:
E-Mail Address:
Street Address:
55 RejeanRoad, Southington, CT
Summary of Conversation
Ql: What is your overall impression of the project?
Al: Everything seems fine.
Q2: Do you have any health related concerns with respect to the landfill site?
A2: No, I don't think so.
Q3: Do you have any other general concerns with the Site?
A3: No.
Q4: Is there any information that you wish to share that might be of use to EPA?
A4: No, not that I recall
Page 1 of 1
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APPENDIX F
REVISED OSL TREND ANALYSIS AND INFORMATION UPDATE
TECHNICAL MEMORANDUM
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nobis
Draft Trend Analysis and Information
Update Technical Memorandum
Old Southington Landfill Superfund Site
Southington, Connecticut
Long-Term Response Action
EPA Task Order No. 0017-RXME-0158
REMEDIAL ACTION CONTRACT
No. EP-S1-06-03
FOR
US Environmental Protection Agency
Region 1
BY
Nobis Group
Nobis Project No. 80017
March 2020
U.S. Environmental Protection Agency
Nobis Group
Region 1
Lowell, Massachusetts
5 Post Office Square, Suite 100
Concord, New Hampshire
Boston, Massachusetts 02109-3912
Phone (800) 394-4182
www.nobis-group.com
V
-------
nobis
Draft Trend Analysis and Information
Update Technical Memorandum
Old Southington Landfill Superfund Site
Southington, Connecticut
Long-Term Response Action
EPA Task Order No. 0017-RXME-0158
REMEDIAL ACTION CONTRACT
No. EP-S1-06-03
For
US Environmental Protection Agency
Region 1
By
Nobis Group
Nobis Project No. 80017
March 2020
Digitally signed by Liyang Chu
DN: cn=Liyang Chu, o=Nobis
Engineering, Inc., ou,
emaiMchu@nobiseng.com, c=US
Date: 2020.03.19 16:27:57 -04'00'
Liyang Chu
Sr. Project Manager
MA-4652-2020-D
Nobis Engineering, Inc.
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TABLE OF CONTENTS nobis
DRAFT TECHNICAL MEMORANDUM
DATA TRENDS ANALYSIS AND INFORMATION UPDATE
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
FEBRUARY 2020
SECTION PAGE
1.0 INTRODUCTION 1
2.0 INFORMATION REVIEW 1
2.1 (I) Current Land Use 1
2.2 (I) New Developments or Structures 2
2.3 (IV) Data Review 2
2.4 (V) Question B - Changes in Standards and TBCs 5
3.0 SUPPLEMENTAL INFORMATION... 7
3.1 (II) Status of Implementation - Institutional Controls (ICs) 7
3.2 (II) Status of Implementation - Systems Operations/O&M 9
3.3 (IV) Site Inspection 9
3.4 (V) Question A - Implementation of IC and Other Measures 10
3.5 (VI) Other Findings 11
TABLES
NUMBER
1 Concentration Trends by Well and Analyte - 2015 to 2019
2 Significant Concentration Changes by Well
3 Regional Kendall Test (S) - Summary of Grouped Well Results
4 Summary of Planned and/or Implemented ICs
5 Roles and Responsibilities
FIGURE
NUMBER
1 Monitoring Well Locations
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Frvg,neerf iq a Suste nzbte I u Vre
TABLE OF CONTENTS (cont.)
DRAFT TECHNICAL MEMORANDUM
DATA TRENDS ANALYSIS AND INFORMATION UPDATE
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
FEBRUARY 2020
APPENDICES
A References List
B Aerial Images
C Mann-Kendall And Regional Kendall Analyses
D Contaminants by Well Graphs
E Landfill Inspection Report and Photographs, September 2019
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1.0 INTRODUCTION
As requested by the U.S. Environmental Protection Agency (EPA), Nobis Engineering, Inc. (dba
Nobis Group) compiled, reviewed, and summarized information for the Old Southington Landfill
Superfund Site (the Site) located in Southington, Connecticut. This work was performed under
Task Order Number 0017-RXME-0158. Per EPA's request, Nobis reviewed available reports and
groundwater data from 2015 to 2019 and assessed compliance of groundwater data with
Applicable or Relevant and Appropriate Requirements (ARARs).
2.0 INFORMATION REVIEW
The data and information review will be used to support EPA s 2020 Five-Year Review (FYR).
The following sections include information requested by EPA (i.e., data review, ARARs review,
land use changes, etc.). The information has been prepared in such a way to ease integration
into the FYR report. Each subsection below is marked with the FYR template section number (I-
VII) for reference. Tables and Appendices referenced in the following sections are included at the
end of this memorandum. Appendix A provides a list of reports referenced within this
memorandum.
2.1 (I) Current Land Use
Currently, the Site is home to a closed municipal landfill. The northern portion of the capped landfill
is accessible for passive recreational use. The southern portion of the capped landfill is fenced
and locked. Access by Performing Settling Defendants (PSDs) is primarily for landscaping and
general operations and maintenance (O&M) of capped landfill. The Chuck & Eddie's Used and
New Auto Parts Property (Chuck & Eddie's) is home to an active used automotive parts business
and salvage yard. Entry into the salvage yard is limited by some barriers and access into the yard
by the public is through the main office building. A network of monitoring wells (G302A; G303A;
G304A, B, C; G312A, B, C; G313A; GZ-5M, S) used in the Cap Effectiveness long-term
monitoring program are located along the eastern perimeter of this property. The Radio Station
Property is home to an active radio station, WNTY 990 AM. Access to the property is open to the
public and monitoring wells are located along the southern perimeter of this property (EPA, 2018).
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2.2 (!) New Developments or Structures
The 2018 Closeout Report (EPA, 2018) included the review of aerial images spanning April 1991
to 2018, Also documented in the Report was the November 2017 Closeout Inspection that
included visual observations of the three properties for new structures or construction activity. The
images review the three properties of interest (the Site, Chuck & Eddie's Used and New Auto
Parts Property, and Radio Station Property). Copies of these images, along with updated images
from 2019, are included in Appendix B. The status of each property is as follows:
• The Site: After completion of the 2001 remedial action, post-capping of the former landfill,
no additional structures were constructed at the capped landfill (Operable Unit 1). No new
structures or evidence of construction activities were noted at the capped landfill during
the 2015 - 2019 review period.
• Chuck & Eddie's Used and New Auto Parts Property: After the 2006 Record of Decision
(ROD), a fabric structure building was erected on a slab foundation during 2011 to support
dismantlement of defunct vehicles. A vapor barrier was installed under the concrete slab
floor as a passive vapor mitigation system to prevent potential groundwater vapor intrusion
into the structure (Operable Unit 2). No new structures or construction activities were
observed at the Chuck & Eddie's property during the 2015 - 2019 review period.
• Radio Station Property: No additional structures or construction activities were identified
at this property during the 2015 - 2019 review period.
In 2018, the Town and PSDs entered into discussions with Symbiont Energy into the construction
of a solar farm on the Site. The installation of a passive ballasted solar system was discussed in
December 2018. At this time no additional information is available regarding the possible re-
development of and/or the future use of the Site as a solar farm.
2.3 (IV) Data Review
Semi-annual sampling of the monitoring wells network is performed to provide information
regarding the groundwater quality downgradient of the Site. Sampling results from March 2015
through September 2019 (a total of 10 sampling events) were reviewed for this FYR. Review of
the 2015 to 2019 sampling results presented in the current cap effectiveness monitoring report
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indicated the continuing presence and elevated concentrations of multiple volatile organic
compounds (VOCs) that include chlorinated ethenes, chlorinated ethanes, aromatic
hydrocarbons, and ketones in multiple wells in the monitoring network (Loureiro, 2019). However,
the aquifer downgradient of the capped landfill is classified as GB and is therefore unsuitable for
use as a potable supply. Although some of the groundwater concentrations do exceed the
Connecticut regulations for Groundwater Volatilization Criteria, the potential threat due to vapor
intrusion was addressed by the PSDs' 2011 investigations, which indicated vapor intrusion did
not pose uncontrolled risks to human health at the Site (Loureiro, 2012).
Groundwater monitoring is the primary method that is performed to evaluate cap effectiveness.
Statistical analysis was performed to evaluate temporal trends of chemical concentrations in
groundwater. Groundwater chemistry data were initially evaluated on a well-by-well basis and
subsequently the same data were combined based on screened interval (i.e., shallow, medium
and deep depths) and trend analyses were conducted for the same suite of chemicals for each
screened interval. Appendix C presents the trends analysis using the Mann-Kendall and the
Regional Kendall statistical analyses.
Specifically, chemical trends were evaluated for benzene, chloroethane, cis-1,2-dichloroethene
(DCE), ethyl benzene, tetrachloroethylene (PCE), trichloroethylene (TCE), vinyl chloride and total
xylenes. Select wells (where data existed) were also evaluated for a combination of acetone; 1,2-
dichloroethane (1,2-DCA); 1,1-dichloroethane (1,1-DCA); methyl isobutyl ketone (MIBK); toluene;
trans-1,2-dichloroethene (trans-1,2-DCE); and tetrahydrofuran.
As presented in Table 1, summary of Mann-Kendall analyses, for the majority of VOCs evaluated,
there were no statistically significant trend changes in concentrations during the 2015 to 2019
observation period. For many wells, VOCs were not detected. Increasing trends were noted in
G304A (vinyl chloride), G312B (PCE), and GZ-5M (benzene). Table 2 shows all the significant
concentration changes on a well-by-well basis. Graphical presentations for the chemical and well
combinations listed in Table 2 are available in Appendix C.
Table 3 presents the concentration trends by aquifer depth (shallow, intermediate, and deep).
When grouped by depth, VOC concentration showed no statistically significant change in
concentration trends. These results are not surprising given the high frequency of non-detects
(i.e., low frequency of detects) observed for many VOCs throughout the three intervals evaluated.
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Monitoring well G303A (shallow depth) had several spikes in vinyl chloride detection (Appendix
D), which account for the statistical "no trend" for this VOC. No other VOCs were routinely
detected for G303A.
Monitoring well G304A (shallow depth) groundwater samples continues to have the greatest
number of VOCs detected and at the highest concentrations. Decreasing trends of ethylbenzene
and total xylene concentrations are noted. However, vinyl chloride concentrations have increased
between 2015 and 2019. The spike in chlorinated VOC concentrations (specifically cis-1,2-DCE
and TCE-equivalents) in G304A coincide with a decrease in groundwater elevations (Loureiro,
2019). A light non-aqueous phase liquid (LNAPL) was reported in G304A with an apparent
thickness of 0.18 ft in March 2018 and 0.01 feet in September 2019. LNAPL has been sporadically
detected in this monitoring well since 2002. G304A is located immediately downgradient of the
Semi-Solid Disposal Area 1 (SSDA-1), which also had an apparent thickness of 0.01 feet of
LNAPL present.
Monitoring well GZ-5M (intermediate depth) located in the groundwater plume and near G304A,
continues to show fluctuating concentrations of VOCs. Cis-1,2-DCE concentrations decreased
between September 2015 and March 2019, and then proceeded to increase sharply in September
2019. Benzene concentrations have been increasing between 2015 and 2019, while chloroethane
concentrations have been consistently decreasing. Vinyl chloride concentrations appear to be
consistent and low during the last five years.
Monitoring well GZ-5S (shallow depth) had statistical increases on cis-1,2-DCE and TCE between
September 2016 and September 2018, but concentrations decreased in March 2018 and have
remained relatively low since. TCE and DCE concentrations are consistently lower in in GZ-5S
than in GZ-5M.
Monitoring well G312B (intermediate depth) had statistical increase on PCE concentrations
between March 2015 and September 2019, and probable increases of TCE during the same time
period. Prior to September 2017, TCE had not been detected in G312B since December 2006.
Monitoring well G312C (deep depth) had a statistical decrease on chloroethane and probable
increases for benzene, cis-1,2-DCE, and vinyl chloride (Appendices A and B).
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Although there have been statistical trend changes for some VOCs in select wells, this is
consistent with the nature of releases from an unlined landfill subject to fluctuating water table
conditions.
Increased ratios of daughter products (e.g. cis-1,2-DCE and vinyl chloride) to parent products
(e.g. PCE and TCE) are present and indicate that over time biodegradation is occurring. The
highest concentrations to date of cis-1,2-DCE were detected in G304B, GZ-5S, and G312C
between March 2017 to March 2019. With a few exceptions, VOCs in groundwater are generally
within the range of historically detected concentrations. Therefore, the landfill cap at the Site is
functioning as designed and expected.
2.4 (V) Question B - Changes in Standards and To-Be-Considered (TBC) Information
Connecticut Remediation Standards Regulations (RSRs)
The 2006 ROD included the Regulations of Connecticut State Agencies, Remediation Standard,
Sections 22a-133k-1 through 22a-133k-3 as an applicable chemical-specific and action-specific
ARAR (EPA, 2006). The RSRs were promulgated in 1996 and amended in June 2013. In July
2019, the Connecticut Department of Energy and Environmental Protection (CT DEEP) gave
notice that it proposes to adopt another set of amended regulations (Wave 2). The 2008 ROD
identified both the 1996 CT RSRs Groundwater Volatilization Criteria (GWVC) and the 2003
proposed CT RSRs GWVC as groundwater action levels (EPA, 2006). The 2019 proposed
amendments seek to streamline site remediation, clarify language, and address the regulated
community's concerns. These proposed RSR amendments underwent public review and are now
being addressed by CT DEEP. The promulgated regulations were cited as ARARs in the 2006
ROD (EPA, 2006). The RSRs contain numeric and narrative standards for soil and groundwater
remediation and take into consideration factors that include land use, groundwater classification,
and proximity to sensitive receptors and were considered in the selection of the VI remedy.
Although the RSRs were not yet promulgated at the time of the 1994 remedy selection, the
capping remedy met the RSR requirements by preventing direct exposure to contaminated soils
and groundwater through the installation of the cap. As noted in the 2015 FYR, changes in the
2013 RSR amendment do not affect the protectiveness of the OU1 source control remedy
because the cap continues to prevent direct exposure to contaminated soils and groundwater.
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The Connecticut RSRs also contain numeric and narrative standards to address volatilization of
soil gas and groundwater contaminants. CT DEEP proposed revised groundwater and soil gas
volatilization criteria in 2003. The CT DEEP's 2003 proposed GWVC for TCE was 27 pg/L. The
2013 GWVC for TCE is 219 pg/L The proposed 2019 amendments include updates to the
volatilization criteria for chlorinated VOCs, including TCE. The 2019 proposed amendments bring
the GWVC for TCE back to 27 pg/L. For vinyl chloride, the proposed GWVC changes from 2 pg/L
in 2013 to 1.6 pg/L for the 2019 proposed value, which is equal to the proposed 2003 criteria.
Changes in the 2013 RSR amendment and proposed 2019 RSR amendments do not affect the
protectiveness of the remedy because no soil vapor results were found to exceed volatilization
criteria and the VI investigation report used the proposed 2003 criteria, which are lower than the
2013 RSRs (Loureiro, 2012).
As indicated previously, the groundwater underlying and downgradient of the capped landfill is
classified as GB and is not suitable for use as a potable supply.
EPA Vapor Intrusion Screening Levels (VISLs)
The 2006 ROD identified the EPA Draft Subsurface Vapor Intrusion Guidance (EPA, 2002), which
established groundwater and soil gas screening levels protective of potential vapor intrusion, as
an additional TBC. That guidance and the screening levels within it have been replaced by the
Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from Subsurface
Vapor Sources to Indoor Air (EPA, 2015) and updated the VISLs electronic calculator to develop
media-specific risk-based VISLs for groundwater, soil gas, and indoor air (EPA, 2015). The Vapor
Intrusion Guide recommends use of risk-based screening VISLs to screen for a potential vapor
intrusion pathway.
In February 2018, EPA launched an online VISL calculator that 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 (RSLs) for toxicity values
and physiochemical parameters and is automatically updated during the semi-annual RSL
updates. Details on how to use the VISL calculator are found in the User's Guide1. The most
recent update was November 2019 and it included updated toxicity and physiochemical
1 https://www.epa.gov/vaporintrusion/vapor-intrusion-screeninq-level-calculator
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parameters. The current VISL for TCE in groundwater at residential and commercial properties
are 1,19 pg/L and 7.43 pg/L, respectively, calculated using the VISL calculator, based on a target
cancer risk of 1x10*. These screening levels are more stringent than the RSR residential and
commercial GWVC (2013 RSRs) action levels of 219 |jg/L and 540 pg/L, respectively. The current
VISLs for vinyl chloride in groundwater at residential and commercial properties are 0.147 pg/L
and 2.45 pg/L, respectively. The residential screening level is also more stringent than the RSR
residential and commercial GWVC (2013 RSR) action level of 2 ug/L.
The vapor intrusion investigations in 2011 concluded that vapor intrusion is not posing
uncontrolled risks to human health at the Site (Loureiro, 2012).
3.0 SUPPLEMENTAL INFORMATION
Nobis has included the following supplemental information for EPA's information and in support
of the FYR. The information has been prepared in such a way to ease integration into the FYR
report.
3.1 (II) Status of Implementation - Institutional Controls (ICs)
The ICs present at the Site are summarized below and in Table 4.
The September 14, 2010 Declaration of Land Use Restrictive Covenant (Environmental
Restriction) was executed by the Town of Southington for the three Town-owned parcels located
in the northern area of the capped landfill. In the restrictive covenant, the Town agreed to: 1) place
notice of the restriction on the deed, title, or other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that will disturb any of the remedial measures
(except for maintenance and repair upon prior approval by EPA); 3) prohibit any activities that
could result in exposure to contaminants in the subsurface soils and groundwater; 4) prohibit any
future residential and commercial development on the property; 5) prohibit use or consumption of
contaminated groundwater underlying the property; 6) grant access to EPA, including its
contractors, and the State for the purpose of conducting any activity related to the Consent
Decrees. Finally, EPA, the State and/or the PSDs have the right to enforce the restrictions. The
April 9, 2018 Declaration of Land Use Restrictive Covenant (Environmental Restriction) was
implemented for one Town- owned parcel located in the southern area of the capped landfill,
which has the same restrictions as the September 2010 restrictive covenant.
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The September 17, 2015 Declarations of Environmental Land Use Restrictive Covenant was
implemented by the CT DEEP for the remaining nine state-owned parcels of the landfill. This
Covenant has the same six restrictions as described in the September 2010 Covenant, and one
restriction that requires any new structure to be constructed in accordance to a plan approved by
EPA that minimizes the risk of inhalation of contaminants. In addition, this Covenant indicates
EPA and/or the PSDs have the right to enforce the restrictions.
The April 19, 2017 Declaration of Environmental Land Use Restriction (ELUR) was recorded by
the owners of the Radio Station Property. In this ELUR, the owners agreed to: 1) restrict the
construction of a building over groundwater at the Subject Area where volatile organic compounds
concentrations exceed the RCSA Section 22a-133k-l(75) Volatilization Criteria (unless a release
is obtained from the CT DEEP); 2) allow no action or inaction would allow a risk of pollutant
migration, or potential hazard to human health or the environment; or result in the disturbance of
structural integrity of engineering controls used to contain pollutants or limit human exposure; 3)
in the event of an emergency, notify the CT DEEP, implement measures to limit actual or potential
risks to human health and the environment, implement a plan to ensure restoration of the property
to conditions prior to the emergency; 4) not allow alterations to the property inconsistent with the
ELUR until a release is approved by the CT DEEP; 5) allows access to the CT DEEP agents that
perform pollution remediation activities; 6) allow access onto the property by the CT DEEP upon
reasonable notice; 7) require the property owner to notify any future interests of the ELUR
requirements. This ELUR is enforceable by the CT DEEP.
The June 22, 2017 Declaration of ELUR was recorded by the owner of the property where the
C&E's Used Auto Parts business is located. This ELUR has the same seven restrictions as
described in the April 2017 ELUR.
The April 9, 2018 Declaration of Land Use Restrictive Covenant (Environmental Restriction) was
implemented for one Town-owned parcel located in the southern area of the capped landfill, which
has the same restrictions as the September 2010 restrictive covenant.
The April 9, 2018 Declaration of Land Use Restrictive Covenant (Environmental Restriction) was
implemented for one Town-owned parcel located in the southern area of the capped landfill, which
has the same restrictions as the September 2010 restrictive covenant.
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3.2 (II) Status of Implementation - Systems Operations/O&M
O&M at the Site is performed by the PSDs. Table 5 lists the roles and responsibilities for managing
the Site after the deletion of the Site from the National Priorities List (EPA, 2018).
The effectiveness of the cap is monitored and inspected on a semi-annual basis. Additionally,
groundwater samples are collected and analyzed semi-annually (March and September). The
cover system is repaired as needed. The landfill is inspected monthly by the Town of Southington.
During the reporting period the following issues were repeatedly identified during the monthly
landfill inspections:
• Black Pond discharge swale needs to be cleaned of brush/vegetation.
• South drainage swale needs to be cleared of brush.
• Clear brush inside fence at GV1 and GVO.
• Clear brush around G304A, G303A, G302A.
• Clear brush around perimeter fence and monitoring wells off-site.
During the last five years (2015-2019) the following repairs have been performed at the Site:
• February 2019 - Fence and post were repaired following a car accident that damaged the
fence between six posts at the entrance to the LCI Yard. The fence was repaired and no
damaged was identified to the landfill liner.
• May 2019 - following the deletion of the Site from the National Priorities List, 27 vapor
probes were abandoned in-place along Rejean Road and Amanda Road to the north of
the Site.
• Summer 2019 - the pipe leading from the Black Pond Swale to the catch basin and the
pipe leading from the catch basin to the discharge on the opposite side of Old Turnpike
Road was replaced.
3.3 (IV) Site Inspection
The inspection of the Site was split into two events, one conducted on September 4, 2019 and a
second on November 21, 2019. During the September event, the Site was visited as part of the
semi-annual Cap Effectiveness groundwater sampling event and in attendance were two
MA-4652-2020-D
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representatives from the PSD's consultant Lourerio Engineering Associates (Lourerio) and James
Harrington, Nobis Group. During the November event, the landfill property, as well as, Chuck &
Eddie's and the Radio Station properties were inspected and in attendance were Almerinda Silva,
USEPA, Christopher Kelly, USEPA, Courtney Carroll, USEPA, and Joseph Trzaski, Lourerio. The
purpose of the inspection was to assess the protectiveness of the remedy.
The September 2019 site observations were performed in conjunction with oversight of the Cap
Effectiveness groundwater sampling event (Nobis, 2019). Lourerio performed groundwater
sampling at 12 groundwater monitoring wells. Nobis noted no discrepancies or issues during the
groundwater sampling oversight. The landfill inspection report and photographs are included as
Appendix E. The landfill appeared to be in good overall condition. The following observations
were made:
• An area of bulging was observed in the southern portion of the landfill, approximately 45
feet east of GV-2. The building encompassed an area of approximately 10 feet in diameter,
elevated about 8 inches above the surface of the surrounding cover.
• Excessive overgrowth of vegetation was observed along the southern perimeter.
• Damage to the fence post was observed opposite the entrance to Chuck & Eddie's Used
Auto Parts.
• Black Pond discharge swale was very overgrown with low-growing vegetation and the
drain at the western end of the swale was becoming overgrown, which is impeding water
flow from exiting the swale.
3.4 (V) Question A - Implementation of IC and Other Measures
ICs are currently in-place for the capped landfill, as detailed in Table 4, which prohibit future
development, disturbance of the cap, use of groundwater, and require any new structures to be
constructed in accordance with to a plan approved by EPA to minimize the risk of inhalation of
contaminants. ICs are also in-place for the two properties downgradient of the landfill (Chuck &
Eddie's Property and the Radio Station Property), as detailed in Table 4, which restrict
construction of buildings in areas where vapor intrusions risks are present.
ICs, including cap maintenance and deed restrictions, are in-place to limit future activities that
could result in accidental intrusion into the cap, accidental exposures to the wastes, and damage
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of the cap system. Landfill inspection reports from 2015 through the end of 2019 were reviewed
for this FYR and no major issues were identified.
Biennial site inspections of the two properties downgradient of the landfill, Chuck & Eddie's
Property and the Radio Station Property, are performed in accordance with the June 2018
Remedial Action Completion Report (RACR) for the Site (Loureiro, 2018). The inspections are
performed to ensure the long-term protection of human health and the environment. The most
recently performed inspection was completed in September 2019 by Loureiro. The site inspection
and building records review did not identify any potential issues with the integrity of the ELURs
recorded for the two properties (Loureiro, 2020).
3.5 (VI) Other Findings
in addition, the following are recommendations that were identified during the FYR and may
improve performance of the remedy, but do not affect current and/or future protectiveness:
• Some vegetation encroaching onto perimeter fence along western and southern
perimeters need to be trimmed back or removed. The plants, if unchecked, could damage
the support rods or steel mesh fabric, and compromise the fence integrity.
• Black Pond Drainage swale: Ponded water at culvert inlet. Runoff was observed to drain
into ponded area. Accumulated vegetative matter appears to limit drainage into the culvert.
The outlet on western side of culvert should be cleared to improve drainage and to prevent
ponded water from entering into the capped materials, which could lead to the leaching of
contaminants. The vegetation should be removed to prevent further ponding.
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TABLES
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Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Souttiington Landfill Superfund Site
Southfnglon, Connecticut
February 2020
page 1 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD
(%)
Statistic
Result
Kendall's Tau (T) Result
Trend
Conclusion
S
T
CF
p-value
G302A
G302A
G302A
G302A
G302A
G302A
G302A
G302A
benzene
chloroethane
cis-1,2-dichloroelhene
ethyl benzene
PCE
TCE
Vinyl chloride
xylene
10
10
10
10
10
10
10
10
9
0
1
0
0
0
9
0
90
0
10
0
0
0
90
0
-8
-9
9
0
0
0
-13
9
-0.2
-0.2
0.2
0.0
0.0
0.0
-0.3
0.2
72.9
75.8
75.8
45.6
45.6
45.6
85.4
75.8
0.271
0.242
0.242
0.544
0.544
0.544
0.146
0.242
Stable
(No detects)
No Change
(No detects)
(No detects)
(No detects)
No Change
(No detects)
G303A
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G303A
cis-1,2-dichloroethene
10
1
10
-5
-0.1
63.6
0.364
Stable
G303A
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
TCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G303A
Vinyl chloride
10
9
90
-3
-0.1
56.9
0.431
No Change
G303A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
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Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Souttiington Landfill Superfund Site
Southfnglon, Connecticut
February 2020
page 2 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD
(%)
Statistic
Result
Kendall's Tau (T) Result
Trend
Conclusion
S
T
CF
p-value
G304A
1,1-DCA
10
5
50
-14
-0.3
87.3
0.127
Stable
G304A
1,2-DCA
10
4
40
7
0.2
70.0
0.300
No Change
G304A
Acetone
10
5
50
8
0.2
72.9
0.271
No Change
G304A
benzene
10
6
60
9
0.2
75.8
0.242
No Change
G304A
chioroethane
10
2
20
7
0.2
70.0
0.300
No Change
G304A
cis-1,2-dichloroethene
10
10
100
5
0.1
63.6
0.364
No Change
G304A
ethylbenzene
10
10
100
-32
-0.7
99.9
0.001
*
Decreasing
G304A
MIBK
10
10
100
-5
-0.1
63.6
0.364
Stable
G304A
PCE
10
6
60
18
0.4
93.4
0.066
Prob. Increasing
G304A
TCE
10
7
70
12
0.3
83.2
0.168
No Change
G304A
Tetrahydrofuran
10
6
60
5
01
63.6
0.364
No Change
G304A
Toluene
10
10
100
5
0.1
63.6
0.364
No Change
G304A
trans-1,2-DCE
11
6
54.5455
-7
-0.1
67.6
0.324
No Change
G304A
Vinyl chloride
10
10
100
27
0.6
99.2
0.008
*
Increasing
G304A
xylene
10
10
100
-23
-0.5
97.7
0.023
*
Decreasing
G304B
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304B
chioroethane
10
5
50
19
0.4
94.6
0.054
Prob. Increasing
G304B
cis-1,2-dichloroethene
10
8
80
16
0.4
90.7
0.093
Prob. Increasing
G304B
ethylbenzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304B
PCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G304B
TCE
10
1
10
7
0.2
70
0.300
No Change
G304B
Tetrahydrofuran
10
3
30
-16
-0.4
90.7
0.093
Prob. Decreasing
G304B
Vinyl chloride
10
8
80
18
0.4
93.4
0.066
Prob. Increasing
G304B
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
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Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Souttiington Landfill Superfund Site
Southfnglon, Connecticut
February 2020
page 3 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD
(%)
Statistic
Result
Kendall's Tau (T) Result
Trend
Conclusion
S
T
CF
p-value
G304C
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G304C
cis-1,2-dichloroethene
10
0
0
0
0.0
45.6
0.544
(No detects)
G304C
G304C
G304C
ethyl benzene
PCE
TCE
10
10
10
0
0
10
0
0
100
0
0
-10
0.0
0.0
-0.2
45.6
45.6
78.4
0.544
0.544
0.216
(No detects)
(No detects)
Stable
G304C
G304C
Vinyl chloride
xylene
10
10
0
0
0
0
0
9
0.0
0.2
45.6
75.8
0.544
0.242
(No detects)
(No detects)
G311A
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G311A
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G311A
cis-1,2-dichloroethene
10
0
0
0
00
45.6
0.544
(No detects)
G311A
G311A
ethylbenzene
PCE
10
10
0
0
0
0
0
0
0.0
0.0
45.6
45.6
0.544
0.544
(No detects)
(No detects)
G311A
G311A
TCE
Vinyl chloride
10
10
0
0
0
0
0
0
0.0
0.0
45.6
45.6
0.544
0.544
(No detects)
(No detects)
G311A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G312A
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
G312A
chloroethane
cis-1,2-dichloroethene
10
10
0
0
0
0
-9
0
-0.2
0.0
75.8
45.6
0.242
0.544
(No detects)
(No detects)
G312A
G312A
ethylbenzene
PCE
10
10
0
0
0
0
0
0
0.0
0.0
45.6
45.6
0.544
0.544
(No detects)
(No detects)
G312A
TCE
10
5
50
5
0.1
63.6
0.364
No Change
G312A
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
G312A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
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Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Souttiington Landfill Superfund Site
Southfnglon, Connecticut
February 2020
page 4 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD
(%)
Statistic
Result
Kendall's Tau (T) Result
Trend
Conclusion
S
T
CF
p-value
G312B
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
G312B
chloroethane
10
0
0
-9
-0.2
75.8
0.242
(No detects)
G312B
cis-1,2-dichIoroelhene
10
7
70
8
0.2
72.9
0.271
No Change
G312B
G312B
ethyl benzene
PCE
10
10
0
10
0
100
0
21
0.0
0.5
45.6
96.4
0.544
0.036
~
(No detects)
increasing
G312B
TCE
10
5
50
19
0.4
84.6
0.154
Prob. Increasing
G312B
G312B
Vinyl chloride
xylene
10
10
0
0
0
0
0
9
0.0
0.2
45.6
75.8
0.544
0.242
(No detects)
(No detects)
G312C
benzene
10
10
100
17
0.4
92.2
0.078
Prob. Increasing
G312C
chloroethane
10
8
80
-20
-0.4
95.5
0.045
*
Decreasing
G312C
cis-1,2-dichloroethene
10
10
100
17
04
92.2
0.078
Prob. increasing
G312C
G312C
ethyl benzene
PCE
10
10
0
8
0
80
0
13
0.0
0.3
45.6
85.4
0.544
0.146
(No detects)
No Change
G312C
TCE
10
8
80
15
0.3
89.2
0.108
No Change
G312C
Vinyl chloride
10
5
50
17
0.4
92.2
0.078
Prob. Increasing
G312C
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
G313A
benzene
10
1
10
3
0.1
56.9
0.431
No Change
G313A
G313A
chloroethane
cis-1,2-dichloroethene
10
10
1
1
10
10
9
9
0.2
0.2
75.8
75.8
0.242
0.242
No Change
No Change
G313A
G313A
ethyl benzene
PCE
10
10
0
0
0
0
0
0
0.0
0.0
45.6
45.6
0.544
0.544
(No detects)
(No detects)
G313A
TCE
10
0
0
0
0.0
45.6
0.544
(No detects)
G313A
Vinyl chloride
10
4
40
16
0.4
90.7
0.093
Prob. Increasing
G313A
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Nobis Engineering, Inc.
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Table 1
Concentration Trends by Well and Analyte - 2015 to 2019
Old Souttiington Landfill Superfund Site
Southfnglon, Connecticut
February 2020
page 5 of 5
Well ID
Analyte
Total No. of
Analyses
No. of
Detections
FOD
(%)
Statistic
Result
Kendall's Tau (T) Result
Trend
Conclusion
S
T
CF
p-value
GZ-5M
benzene
10
4
40
23
0.5
97.7
0.023
*
Increasing
GZ-5M
chloroethane
10
10
100
-33
-0.7
99.9
0.001
*
Decreasing
GZ-5M
cis-1 »2-dichloroethene
10
10
100
-18
-0.4
93.4
0.066
Prob. Decreasing
GZ-5M
GZ-5M
ethylbenzene
PCE
10
10
0
9
0
90
9
9
0.2
0.2
75.8
75.8
0.242
0.242
(No detects)
No Change
GZ-5M
TCE
10
10
100
-14
-0.3
87.3
0.127
Stable
GZ-5M
trans-1,2-DCE
10
5
50
-7
-0.2
70.7
0.293
No Change
GZ-5M
Vinyl chloride
10
10
100
-6
-0.1
66.8
0.332
Stable
GZ-5M
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
GZ-5S
benzene
10
0
0
0
0.0
45.6
0.544
(No detects)
GZ-5S
chloroethane
10
0
0
-9
-02
75.8
0.242
(No detects)
GZ-5S
cis-1,2-dichtoroethene
10
10
100
-4
-0.1
60.3
0.397
Stable
GZ-5S
GZ-5S
ethylbenzene
PCE
10
10
0
1
0
10
0
9
0.0
0.2
45.6
75.8
0.544
0.242
(No detects)
No Change
GZ-5S
TCE
10
9
90
0.17
0.0
92.2
0.078
Prob. Decreasing
GZ-5S
Vinyl chloride
10
0
0
0
0.0
45.6
0.544
(No detects)
GZ-5S
xylene
10
0
0
9
0.2
75.8
0.242
(No detects)
Abbreviations:
CF - Correlation factor
FOD - Frequency of Detection
S - Kendall test statistic
X - Kendall's tau correlation coeffcient
Nobis Engineering, Inc.
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Table 2
Significant Concentration Changes by Wei!
Old Southington Landfill Superfund Site
February 2020
CHEMICAL
WELLS WITH SIGNIFICANT
INCREASE
WELLS WITH SIGNIFICANT
DECREASE
Chloroethane
G312C, GZ-5M
Vinyl chloride
G304A
Tetrachloroethene (PCE)
G312B
Benzene
GZ-5M
Ethylbenzene
G304A
Xylene
G304A
Note: Based on Mann-Kendall trends analysis for semi-annual groundwater sampling performed between
2015 to 2019.
Nobis Engineering, Inc.
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Table 3. Regional Kendall Test (S) - Summary of Grouped Well Results
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Shallow Monitoring Well ID
Anaiyte
Total # of
#of
FOO (%)
Statistic
S) Result
Trend Conclusion*
Analyses
Detections
S
p-value
1,1-DichIoroethane
80
26
32.5%
-9.0
02399
No change
1,2-Dichloroe thane
80
7
8.8%
-1.0
1.000
No change
Acetone
80
9
11.3%
-3.0
0.6134
No change
Benzene
80
27
33.8%
-1.0
1.000
No change
Chloroethane
80
4
5.0%
0.0
1.000
No change
cis-1,2-DCE
80
33
41.3%
10.0
0.2346
No change
Ethylbenzene
80
20
25.0%
-6.0
0.2207
No change
MIBK
80
20
25.0%
2.0
0.8065
No change
Tetrachloroethylene (PCE)
80
11
13.8%
-7.0
0.2174
No change
Tetrahydrofuran
80
12
15.0%
9.0
0.1551
No change
Toluene
80
20
25.0%
4.0
0.4624
No change
trans-1,2-DCE
80
12
15.0%
-5.0
0.4470
No change
Trichloroethylene (TCE)
80
23
28.8%
-5.0
0.5677
No change
Vinyl Chloride
80
42
52.5%
11.0
0.2172
No change
Xylenes, total
80
20
25.0%
-6.0
0.2207
No change
Intermediate iVIoopsorincj Wpm II!)
Anaiyte
Total # of
# of
FOO (%)
Statistic
S) Result
Trend Conclusion*
Analyses
Detections
S
p-value
1,1-Dichloroethane
39
5
13%
-5.0
0.312
No change
1,2-Dichloroethane
39
0
0%
-
-
(No detects)
Acetone
39
0
0%
-
-
(No detects)
Benzene
39
8
21%
7.0
0.1296
No change
Chloroethane
39
24
62%
-2.0
0.8582
No change
cis-1,2-DCE
39
30
77%
1.0
1.000
No change
Ethylbenzene
39
0
0%
-
-
(No detects)
MIBK
39
0
0%
-
-
(No detects)
Tetrachloroethylene (PCE)
39
25
64%
8.0
0.2253
No change
Tetrahydrofuran
39
4
10%
-5.0
0.3122
No change
Toluene
39
0
0%
-
-
(No detects)
trans-1,2-DCE
39
12
31%
3.0
0.7135
No change
Trichloroethylene (TCE)
39
25
64%
7.0
0.3448
No change
Vinyl Chloride
39
27
69%
2.0
0.8625
No change
Xylenes, total
39
0
0%
-
.
(No detects)
Deep Monitoring Well ID
Anaiyte
Total # of
# of
FOD (%)
Statistic i
S) Result
Trend Conclusion*
Analyses
Detections
S
p-value
1,1-Dichloroethane
20
5
25%
7.0
0.1296
No change
1,2-Dichloroethane
20
0
0%
-
-
(No detects)
Acetone
20
0
0%
-
-
(No detects)
Benzene
20
1
5%
2.0
0.7237
No change
Chloroethane
20
8
40%
-6.0
0.2207
No change
cis-1,2-DCE
20
10
50%
6.0
0.2207
No change
Ethylbenzene
20
0
0%
-
-
(No detects)
MIBK
20
0
0%
-
-
(No detects)
Tetrachloroethylene (PCE)
20
2
10%
7.0
0.0961
No change
Tetrahydrofuran
20
0
0%
-
-
(No detects)
Toluene
20
0
0%
-
-
(No detects)
trans-1,2-DCE
20
1
5%
2.0
0.7237
No change
Trichloroethylene (TCE)
20
18
90%
-2.0
0.8625
No change
Vinyl Chloride
20
5
25%
5.0
0.3122
No change
Xylenes, total
20
0
0%
-
-
(No detects)
*A statistically significant trend is identified if p-value < 0.05
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 1 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
Documents
Impacted
Pareel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
Landfill Cap, Soil,
and Indoor Air
Yes
Yes
Three Town-
owned parcels
in northern
area of capped
landfill:
(1)425 Old
Turnpike
Road, Map 64,
Lot 22
(2)435 Old
Turnpike
Road, Map 64,
Lot 23
(3) 84 Rejean
Road, Map 65,
Lot 46
In the restrictive covenant, the Town agreed to: I)
place notice of the restriction on the deed, title, or
other instrument and have It continue into perpetuity;
2) prohibit any use of any portion of the property that
will disturb any of the remedial measures (except for
maintenance and repair upon prior approval by
EPA); 3) prohibit any activities that could result in
exposure to contaminants in the subsurface soils and
groundwater; 4) prohibit any future residential and
commercial development on the property; 5) prohibit
use or consumption of contaminated groundwater
underlying the property; 6) grant access to EPA,
including its contractors, and the State for the
purpose of conducting any activity related to the
CDs.
Declaration of Land
Use Restrictive
Covenant
(Environmental
Restriction)
executed by Town
of Southington, CT
on September 14,
2010
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 2 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
.imu'iiis
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
Landfill cap. Soil,
and Indoor Air
Yes
Yes
Nine
remaining
State-owned
parcels of the
landfill
(1)413 Old
Turnpike
Road Map 64,
Lot 21
(2)455 Old
Turnpike
Road, Map 64,
Lot 24
(3) 101 Rejean
Road, Map 64,
Lot 20
(4) 477 Old
Turnpike
Road, Map 64,
Lot 25
In the restrictive covenant, the State agreed to: 1)
place notice of the restriction on the deed, title, or
other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that
will disturb any of the remedial measures (except for
maintenance and repair upon prior approval by
EPA); 3) prohibit any activities that could result in
exposure to contaminants in the subsurface soils and
groundwater; 4) prohibit any future residential and
commercial development on the property; 5) prohibit
use or consumption of contaminated groundwater
underlying the property; 6) grant access to EPA,
including its contractors, and the State for the
purpose of conducting any activity related to the
CDs; 7) any new structure to be constructed in
accordance to a plan approved by EPA that
minimizes the risk of inhalation of contaminants.
ELUR recorded on
September 17,2015
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 3 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
IIIIU'IIIS
Impacted
Pareel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
(5)485 Old
Turnpike
Road, Map 64,
Lot 27
(6) 503 Old
Turnpike
Road, Map 64,
Lot 29
(7) 497 Old
Turnpike
Road, Map 64,
Lot 30
(8) 597 Old
Turnpike
Road, Map 53,
Lot 127
(9) 601 Old
Turnpike
Road, Map 53,
Lot 128
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 4 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
Ultil'MlS
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
Indoor Air
Yes
Yes
Radio Station
Property, 440
Old Turnpike
Rd
Map 064, Lot
047
In the restrictive covenant, the property owners
agreed to: 1) restrict the construction of a building
over groundwater at the Subject Area where volatile
organic compounds concentrations exceed the RCSA
Section 22a-133k-l(75) Volatilization Criteria (unless
a release is obtained from the CT DEEP); 2) allow no
action or inaction would allow a risk of pollutant
migration, or potential hazard to human health or the
environment; or result in the disturbance of structural
integrity of engineering controls used to contain
pollutants or limit human exposure; 3) in the event of
an emergency, notify the CT DEEP, implement
measures to limit actual or potential risks to human
health and the environment, implement a plan to
ensure restoration of the property to conditions prior
to the emergency; 4) not allow alterations to the
property inconsistent with the ELUR until a release is
approved by the CT DEEP; 5) allows access to the
CT DEEP agents that perform pollution remediation
activities; 6) allow access onto the property by the
CT DEEP upon reasonable notice; 7) require the
property owner to notify any future interests of the
ELUR record on
April 19,2017
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 5 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
¦UltH'fllS
Impacted!
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
ELUR requirements. This ELUR is enforceable by
the CT DEEP.
Indoor Air
Yes
Chuck &
Eddie's Used
Auto Parts
Property, 450
Old Turnpike
Rd
Map 064, Lot
046
In the restrictive covenant, the property owners
agreed to: 1) restrict the construction of a building
over groundwater at the Subject Area where volatile
organic compounds concentrations exceed the RCSA
Section 22a-I33k-l(75) Volatilization Criteria (unless
a release is obtained from the CT DEEP); 2) allow no
action or inaction would allow a risk of pollutant
migration, or potential hazard to human health or the
environment; or result in the disturbance of structural
integrity of engineering controls used to contain
pollutants or limit human exposure; 3) in the event of
an emergency, notify the CT DEEP, implement
measures to limit actual or potential risks to human
health and the environment, implement a plan to
ensure restoration of the property to conditions prior
to the emergency; 4) not allow alterations to the
ELUR recorded on
June 22,2017
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 6 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
Ultil'MlS
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
property inconsistent with the ELUR until a release is
approved by the CT DEEP; 5) allows access to the
CT DEEP agents that perform pollution remediation
activities; 6) allow access onto the property by the
CT DEEP upon reasonable notice; 7) require the
property owner to notify any future interests of the
ELUR requirements. This ELUR is enforceable by
the CT DEEP,
Landfill cap, Soil,
and Indoor Air
Yes
Yes
One Town-
owned parcel
located in the
southern area
of the capped
landfill
493 Old
Turnpike
Road, Map 63,
Lot 26
In the restrictive covenant, the Town agreed to: 1)
place notice of the restriction on the deed, title, or
other instrument and have it continue into perpetuity;
2) prohibit any use of any portion of the property that
will disturb any of the remedial measures (except for
maintenance and repair upon prior approval by
EPA); 3) prohibit any activities that could result in
exposure to contaminants in the subsurface soils and
groundwater; 4) prohibit any future residential and
commercial development on the property; 5) prohibit
use or consumption of contaminated groundwater
underlying the property; 6) grant access to EPA,
including its contractors, and the State for the
April 9,2018
Declaration of Land
Use Restrictive
Covenant
(Environmental
Restriction)
-------
Table 4
Summary of Planned and/or Implemented ICs
Old Southington Landfill Superfund Site
Old Southington, Connecticut
Page 7 of 7
Media,
engineered
controls, and
areas that do not
support UU/UE
based on current
conditions
ICs
Needed
ICs Called
for in the
Decision
-uim-ins
Impacted
Parcel(s)
IC
Objective
Title of IC
Instrument
Implemented and
Date (or planned)
purpose of conducting any activity related to the
CDs.
-------
TABLE 5
ROLES AND RESPONSIBILITIES
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTH!NGTON, CONNECTICUT
Page 1 of 3
PARTY
AFFILIATION1
RESPONSIBILITIES
CONTROLLING DOCUMENTS
(As appropriate)
U. S. Environmental Protection Agency
Federal regulatory agency
• Oversight of OSt Site to ensure continuing effectiveness of
Records of Decision remedial objectives.
• Review long-term monitoring reports, evaluate groundwater
contaminant tends, and assess need for additional action.
• Review periodic O&M reports, and assess need for additional
action.
• Review inspection reports for compliance with ELURs.
• Prepare Five-Year Reviews to assess protectiveness and
effectiveness of ROD remedies. Assess changes and verify
response actions are performed.
• 1994 Record of Decision
• 2006 Record of Decision
• 1998 Consent Decree
• 2008 Consent Decree
Connecticut Department of Energy and
Environmental Protection
State regulatory agency
• Oversight of 08L Site to ensure continuing effectiveness of
Records of Decision remedial objectives.
• Review long-term monitoring reports, evaluate groundwater
contaminant trends, and assess need for additional action.
® Review periodic O&M reports, and assess need for additional
action.
• Review inspection reports for compliance with ELURs.
• Provide input into Five-Year Reviews.
• 1994 Record of Decision
• 2006 Record of Decision
• Sep. 17,2015 Environmental Land Use
Restrictive Covenant for nine parcels.
* Responsible for Long-Term Monitoring, Operations &
Maintenance of the capped landfill, and biennial ELUR and
Vapor Barrier inspections (delegated to PSDs' contractor).
• 1996 Consent Decree
• 2006 Consent Decree
• Operations and Maintenance Plan {CRA,
2001)
• Vapor Intrusion Inspection Plan, RACR,
Appendix N, 2018
United Technologies Corporation
Performing Settling Defendant
(OU1 and OU2)
-------
TABLE 5
ROLES AND RESPONSIBILITIES
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTH!NGTON, CONNECTICUT
Page 2 of 3
PARTY
AFFILIATION'
RESPONSIBILITIES
CONTROLLING DOCUMENTS
(As appropriate)
Town of Southington, Connecticut
Performing Settling Defendant
-------
TABLE 5
ROLES AND RESPONSIBILITIES
OLD SOUTHINOTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
Page 3 of 3
PARTY
AFFILIATION1
RESPONSIBILITIES
CONTROLLING DOCUMENTS
(As appropriate)
Charles ¥. Areangelo (Chuck & Eddie's
Property)
Owner of 450 Old Turnpike Road,
Southington, CT
• Adherence to ELUR requirements for property.
• June 22,2017 Declaration of Environmental
Land Use Restriction and Grant of Easement
for one parcel.
DGS Holdings, LLC; NES Realty, LLC;
Trustees of Stevens Family Tryst; and
U.D.T (Radio Station Property)
Owners of 440 Old Turnpike Road
Southington, CT
• Adherence to ELUR requirements for property.
• April 19,2017 Environmental Land Use
Restriction and Grant of Easement for one
parcel.
Note 1: The Performing Settling Defendants (PSDs) is a subset of the Settling Defendants (SDs). While the SDs are financially liable for the remedial actions associated with Operable Unit 1 or 2, the
PSDs implement the Operations and Maintenance, Long-term Monitoring, and periodic inspections of the ELURs and Vapor Barrier, and provide input into the Five-Year Reviews.
Abbreviations: EtUR - Environmental Land Use Restrictions; NPL - National Priorities List; OSL- Old Southington Landfill Superfund Site; OU - Operable Unit; RACK - Remedial Action Completion
Report (LEA, 2018)
-------
FIGURE
-------
-------
APPENDIX A
-------
APPENDIX A - REFERENCE LIST
Lourciro Engineering Associates, Inc. (Lourciro), 2012, Vapor Intrusion Groundwater Investigation
Report, Old Southington Landfill, Southington. Connecticut. My.
Loureiro, 2018. Remedial Action Completion Report, Old Southington Landfill, Southington,
Connecticut. lime.
Lourciro, 2019. Re: Cap Effectiveness Monitoring Program Data Report - September 2019, Operations
& Maintenance Plan, Old Southington Landfill, Lourciro Comm. No. 61SL901.003. December 2.
Lourciro, 2020. Re: Biennial Inspection of Environmental Land Use Restrictions, Old Southington
Landfill Site, Southington, Connecticut, Commission Number: 61SL902.001. February 3.
Nobis Engineering, Inc., 2019. Trip Report, September 2019 Groundwater Sampling and Landfill
Inspection, Old Southington Landfill Superfund Site, Southington, Connecticut, Long-Term
Response Action Oversight, Task Order No. 0017-RX-ME-0158. December 30.
U S Environmental Protection Agency (EPA), 2002. OSWER Draft Guidance for Evaluating the Vapor
Intrusion to Indoor Air Pathway from Groundwater and Soils, U.S. Environmental Protection
Agency, Office of Solid Waste and Emergency Response, Washington, DC, EPA/530/D-02/004.
November 2002.
EPA, 2006. Record of Decision Summary. Old Southington Landfill Superfund Site, Southington,
Connecticut September.
EPA, 2015. OSWER Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from
Subsurface Vapor Sources to Indoor Air. OSWER Publication 9200.2-154. June.
EPA, 2018. Final Close Out Report, Old Southington Landfill Superfund Site, Southington, Connecticut.
May.
-------
APPENDIX B
-------
Figure B1. April 1991, Source: Google Earth. Prior to relocation of residences and businesses and capping of Old Southington Landfill.
-------
Figure B2. August 2006. Conditions for OSL, Chuck & Eddie's Used Auto Parts, and Radio Station Property. Source: Google Earth
-------
Figure B3. 2013 March. Fabric structure constructed on Chuck & Eddie's Used Auto Parts property. Source: Google Earth.
-------
Figure B4. 2017 September. Conditions at
OSL, Chuck & Eddie's Used Auto Parts, and Radio Station Property. Source: Google Earth
-------
Figure B5. 2019. Conditions at OSL, Chuck & Eddie's Used Auto Parts, and Radio Station Property. Source: Google Earth
-------
APPENDIX C
-------
APPENDIX C
MANN-KENDALL AND REGIONAL KENDALL ANALYSES
Old Southington Landfill Superfund Site
Old SouthinijtoiK CT
February 2020
1.0 Introduction
As part of the 2020 Old Southington Landfill Five-Year Review, statistical analyses were conducted to
evaluate temporal trends of chemical concentrations in groundwater. Specifically, chemical trends were
evaluated for 1,1-dichloroethane, 1,2-dichloroethane, acetone, benzene, chloroethane, cis-),2
dichloroethylene, ethylbenzene, methyl isobutyl ketone (MIBK), tetrachloroethylene (PCE),
tetrahydrofuran, toluene, trans-1,2-dichloroethylene, vinyl chloride, trichloroethylene (TCI), and xylenes,
total. Data collected at 13 wells from 2015 through 2019 were included in this temporal trends analysis.
Groundwater chemistry data was combined based on screening interval (i.e., shallow, medium and deep)
and trend analyses were conducted for the same suite of chemicals for each screening interval. The
following discussion presents the methodology used to conduct the trend analyses and a brief summary of
the results.
1.1 Technical Approach
1.1.1 Mann-Kendall Statistical Analysis
The USGS has long recommended the Kendall family of tests to determine chemical trends in groundwater
data (Hirsh et al 1982, Hirsh and Slack 1984, Helsel and Hirsh 1992, Helsel et al 2005, and Helsel and
Frans 2006). The Mann-Kendall, the most basic test in this family of tests, is a non-parametric test for
monotonic (single-direction) trends in time series data (i.e., it evaluates whether variables like chemical
concentrations arc consistently increasing or decreasing over time). One benefit of the Mann-Kendall test
is that data need not conform to any particular distribution (e.g., data does not need to be normally
distributed). The Mann-Kendall test computes the Kendall's tau correlation coefficient (x), the Kendall test
statistic (S), the standard normal deviate (z), and the significance of the trend (p). In order to compute x,
data values are evaluated as an ordered time series and each data value is compared to subsequent values.
The results of these comparisons can be +, - or 0 if the later data value is greater than, less than, or equal to
the prior data value, respectively. Each positive comparison is assigned a positive value (0 < x <+1), each
negative comparison is assigned a negative value (-1 < x < 0) and when two data values are equal the
comparison is assigned a value of 0 (note: the magnitude of change in concentrations between time steps is
irrelevant when determining x). The test statistic (S), which is used to calculate x is the sum of the +Ts» -
1 \ and 0's with a null hypothesis of S = 0, or no trend is present in the data. A positive value of 5 indicates
an increasing trend and a negative value indicates a decreasing trend. For this evaluation, a trend is
considered statistically significant if S is different from zero at p-value < 0.05). Dividing the S statistic by
n(n-l)/2 (the number of possible comparisons to be made among n data pairs) is a normalization process
that produces Kendall's x. It should be noted that the Mann-Kendall test statistic does not provide any
indication of the magnitude of the trend; therefore, situations where there is only a substantial initial change
in data values (positive or negative) may not result in a statistically significant test result.
1
Nobis Engineering, Inc.
-------
In an effort to determine if there are trends in groundwater concentrations at different depth intervals, the
wells were assigned to one of three possible depth intervals (i.e., shallow, medium or deep).
The Mann-Kendall statistical analysis of the 2015 - 2019 .groundwater data were developed using the GSI
Mann-Kendall Toolkit. The Mann-Kendall results are presented in the Attachment 1.
1.1.2 Regional Kendall
A Regional Kendall test for trends (Helsel and Frans 2006; USGS 2009) was used to assess concentration
trends by depth interval The Regional Kendall test in this example accounts for depth interval (region) by
computing the Mann-Kendall test on each well within a depth interval separately and then combining the
results. The Regional Kendall test looks for consistency in the direction of trend at each interval (region)
and tests whether there is evidence for a general trend in a consistent direction throughout the interval
{region). The Regional Kendall test will find evidence of a consistent spatial tend when a trend in the same
direction occurs at many individual locations (wells within a depth interval). Failing to reject the null
hypothesis of "no regional trend" may be because there are not trends at most locations, or because
observable trends have opposite directions at different locations, canceling one another out The results of
the Regional Kendall test for the Old Southington Landfill Site groundwater data are presented in Table
C-l.
REFERENCES
GSI Environmental, Inc., 2012. GSI Mann-Kendall Toolkit, Version 1.0. program. Accessible at:
https://www.gsi-net.com/en/software/fTee-software/gsi-mann-kendall-to'''U,it In ml. November.
Hirsh, R.M., J.R. Slack and R.A. Smith. 1982. Techniques of trend analysis for monthly water quality
data. Water Resources Research No. 18, p. 107-121.
Hirsh, R.M. and J.R. Slack. 1984. A nonparametric trend test for seasonal data with serial dependence.
Water Resources Research No.20, p.727-732.
Helsel, D.R. and R.M. Hirsh 1992. Statistical Methods in Water Resources. Amsterdam, Elsevier
Publishers, 529p.
Helsel, D.R., D.K. Mueller and J.R. Slack. 2005. Computer Program for the Kendall Family of Trend
Tests. USGS Scientific Investigation Reports 2005-5275.
Helsel, D.R. and L. M. Frans. 2006. Regional Kendall Test for Trend. Environ. Sci. & Tech. Vol 40,
No. 13, p. 4066-4073.
2
Nobis Engineering, Inc.
-------
USGS. 2009. Regional Kendall Program. Accessible at:
August 18.
3
Nobis Engineering, Inc.
-------
APPENDIX C
ATTACHMENT 1
4
Nobis Engineering, Inc.
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-N0V-19
OSL
KKN
Chloroethane
ug/L
I I I I I I
CHLOROETHANE CONCENTRATION (ug/L)
1
3/9/2015
0.5
0.5
1.6
0.5
0.5
0.5
0.5
2
9/15/2015
0.5
05
05
1.8
0.5
0.5
0.5
3
3/3/2016
0.5
0 5
50
0.5
0.5
0.5
0.5
4
9/26/2016
05
05
0.5
0.5
0.5
0.5
0.5
5
3/13/2017
0.5
0.5
25
0.5
0.5
0.5
0.5
6
9/19/2017
0.5
0.5
12.5
0.5
0.5
0.5
0.5
7
3/8/2018
0.5
0.5
2.8
2.6
0.5
0.5
0.5
8
9/21/2018
0.5
0.5
0.5
1.6
0.5
0.5
0.5
9
3/25/2019
0.5
0.5
25
5.9
0.5
0.5
0.5
10
9/5/2019
0.25
0.25
25
1.9
0.25
0.25
0.25
11
12
13
14
15
16
17
18
19
20
Concentration Trend:
100
Ui
O
2
*-»
c
0)
u
c
o
o
10
0.1
H-
—H
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
06/14 12/14 07/15 01/16 08/16 03/17 OS/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required tor calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend; < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product however, no party, Including without
limitation GSt Environmental inc., makes any representation or warranty regarding the accjracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
Chloroethane
ug/L
I I I I I I
CHLOROETHANE CONCENTRATION (ug/L)
1
6-Mar-15
0.5
4
0.5
4.3
0.5
2
16-Sep-15
0,5
4.6
0.5
2.9
0.5
3
4-Mar-16
0.5
5.7
0.5
4.8
0.5
4
26-Sep-16
05
376
05
2.81
0.5
5
15-Mar-17
0.5
0.5
05
2.3
0.5
6
19-Sep-17
0.5
3.1
05
2
0.5
7
8-MaM8
0.5
5.5
0.5
1.5
0.5
8
21-Sep-18
0.5
2.1
0.5
2.1
0.5
9
26-Mar-19
0.5
0.5
0.5
1.8
0.5
10
4-Sep-19
0.25
1.9
1.1
1.7
0.25
11
12
13
14
15
16
17
18
19
20
I
Coefficient of Variation:
0.17
0.59
0.34
0.43
0.17
I
Mann-Kendal! Statistic (S):
-9
-20
9
-33
-9
I
Confidence Factor:
75.8%
95.5%
75.8%
99.9%
75.8%
I
Concentration Trend:
Stable
Decreasing
No Trend
Decreasing
Stable
O)
O
2
+•*
c
o
o
c
o
o
«
06/f4 f2/f4 07/15 01/16 08/16 03/17 09/17 04/18 10/18 05/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has timn exercised in preparing litis software product; however, no party, Including without
limitation GSt Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
Xylene, Total
u9/l "T
XYLENE, TOTAL CONCENTRATION (ug/L)
1
3/9/2015
0.5
0.5
13000
0.5
0.5
0.5
0.5
2
9/15/2015
0.5
0.5
14000
0.5
0.5
0.5
0.5
3
3/3/2016
0.5
05
17000
0.5
0.5
0.5
0.5
4
9/26/2016
05
0 5
12300
0.5
0.5
0.5
0.5
5
3/13/2017
05
0.5
12000
0.5
0.5
0.5
0.5
6
9/19/2017
0 5
0.5
9300
0.5
0.5
0.5
0.5
7
3/8/2018
0.5
0.5
12000
0.5
0.5
0.5
0.5
8
9/21/2018
0.5
0.5
11000
0.5
0.5
0.5
0.5
9
3/25/2019
0.5
05
13000
0.5
0.5
0.5
0.5
10
9/5/2019
0.75
0 75
7600
0.75
0.75
0.75
0.75
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.1S
0.15
0.21
0,15
0.15
0.15
0.15
Mann-Kendall Statistic (S):
9
9
-23
9
9
9
9
Confidence Factor:
75.8%
75.8%
977%
75.8%
75.8%
75.8%
75.8%
Concentration Trend:
No Trend
No Trend
Decreasing
No Trend
No Trend
No Trend
No Trend
100000
-2 10000
O)
3, 1000
.2 100
S
c 10
0
P
§ '
o
0.1
-+-
H-
-+¦
-4-
-+-
-H
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
06/14 12/14 07/1S 01/16 08/16 03/17 09/17 04/18 10/18 05/19 12/19
Sampling Date
Notes:
1. At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend; < 90% and COV < 1 = Stable.
3. Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans" J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water, 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing this software product; however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall tie liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., irww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
Xylene, Total
ug/L
I I I I I I
XYLENE, TOTAL CONCENTRATION (ug/L)
1
6-Mar-15
0.5
0.5
0.5
0.5
0.5
2
16-Sep-15
0.5
0.5
0.5
0.5
0.5
3
4-Mar~16
05
05
0.5
0.5
0.5
4
26-Sep-16
05
05
0.5
0.5
0.5
5
15-Mar-17
0.5
0 5
05
0.5
0.5
6
19-Sep-17
0.5
0.5
05
0.5
0.5
7
8-Mar-18
0.5
0.5
0.5
0.5
0.5
8
21-Sep-18
0.5
0.5
0.5
0.5
0.5
9
26-Mar-19
0.5
0.5
0.5
0.5
0.5
10
4-Sep-19
0.75
0.75
0.75
1.5
0.75
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.15
0.15
0.15
0.53
0.15
I
Mann-Kendal! Statistic (S):
9
9
9
9
9
I
Confidence Factor:
75.8%
75.8%
75.8%
75.8%
75.8%
I
Concentration Trend:
No Trend
No Trend
No Trend
No Trend
No Trend
10
U)
3
•2 f
c
d)
G
£
O
o
0.1
£
s ¦ ¦ a a ¦ ¦ ¦
H-
—H
-f-
-+-
-G312B
-G312C
-G313A
-GZ-5M
-GZ-5S
06/14 12/14 07/15 01/16 08/16 03/17 OS/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required tor calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product; however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ol this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contested herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
Ethylbenzene
ug/L
ETHYLBENZENE CONCENTRATION (ug/L)
i 1
3/9/2015
025
0 25
10000
0.25
0.25
0.25
0.25
2
9/15/2015
0 25
0.25
10000
0.25
0.25
0.25
0.25
3
3/3/2016
0 25
0 25
13000
0.25
0.25
0.25
0.25
4
9/26/2016
0 25
025
9950
0.25
0.25
0.25
0.25
5
3/13/2017
0 25
0.25
9300
0.25
0.25
0.25
0.25
6
9/19/2017
0 25
0 25
7300
0.25
0.25
0.25
0.25
7
3/8/2018
0.25
0.25
9100
0.25
0.25
0.25
0.25
8
9/21/2018
0.25
0.25
8300
0.25
0.25
0.25
0.25
9
3/25/2019
025
025
8900
0.25
0.25
0.25
0.25
10
9/5/2019
025
0.25
6200
0.25
0.25
0.25
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.00
0.00
0.20
0,00
0.00
0.00
Mann-Kendal! Statistic (S):
0
0
-32
0
10
0
0
Confidence Factor:
45.6%
45.6%
99.9% I 45.6% I 45.6%
45.6%
45.6%
Concentration Trend:
Stable
Stable
Decreasing
Stable
Stable
Stable
Stable
100000
~ 10000
"at
o
2
*-»
c
0)
u
c
o
o
1000
100
10
1
0.1
-+-
H-
-+¦
-H
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
06/14 12/14 07/15 01/16
08/16 03/17 09/17 04/18
Sampling Date
10/18 05/19 12/19
Notes:
1. At least four independent sampling events per well are required for calculating the Trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has timn exercised in preparing this software product however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accjracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
Ethylbenzene
ug/L
I I I I I I I
ETHYLBENZENE CONCENTRATION (ug/L)
1
6-Mar-15
0.25
0 25
025
0.25
0.25
2
16-Sep-15
0.25
0.25
0.25
0.25
0.25
3
4-Mar-16
0 25
025
0 25
0.25
0.25
4
26-Sep-16
025
025
025
0.25
0.25
5
15-Mar-17
025
0.25
0 25
0.25
0.25
6
19-Sep-17
0 25
025
0.25
0.25
0.25
7
8-Mar-18
0.25
0.25
0.25
0.25
0.25
8
21-Sep-18
0.25
0.25
0.25
0.25
0.25
9
26-Mar-19
0.25
0.25
0.25
0.25
0.25
10
4-Sep-19
0.25
0.25
0.25
0.5
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.00
0.00
0.29
0.00 | |
Mann-Kendall Statistic (S):
Confidence Factor:
0
0
9
45.e%
45.6%
75.8%
45.6% | I
Concentration Trend:
Stable
Stable
No Trend
Stable
U)
C
0
u
c
o
o
0.1
A
H-
—H
-G312B
-G312C
-G313A
-GZ-5M
-GZ-5S
06/14 12/14 07/15 01/16 08/16 03/17 OS/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required tor calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% «Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing this software product; however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., irww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
Benzene
ug/L
BENZENE CONCENTRATION (ug/L)
i 1
3/9/2015
5.4
025
11
0.25
0.25
0.25
0.25
2
9/15/2015
4 5
025
25
0.25
0.25
0.25
0.25
3
3/3/2016
6.3
025
25
0.25
0.25
0.25
0.25
4
9/26/2016
4 34
025
8.84
0.25
0.25
0.25
0.25
5
3/13/2017
5.5
0.25
12.5
0.25
0.25
0.25
0.25
6
9/19/2017
5.7
0 25
65
0.25
0.25
0.25
0.25
7
3/8/2018
5.5
0.25
27
0.25
0.25
0.25
0.25
8
9/21/2018
5.6
025
4.8
0.25
0.25
0.25
0.25
9
3/25/2019
0 25
0.25
12.5
0.25
0.25
0.25
0.25
10
9/5/2019
33
025
25
0.25
0.25
0.25
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.38 i 0.00
0.66
0,00
0.00
0.00
Mann-Kendali Statistic (S):
-8 | 0
9
0
10
0
0
Confidence Factor:
72.9% I 45.6%
75.8%
45.6%
45.6%
Concentration Trend:
Stable
Stable
No Trend
Stable
Stable
Stable
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
at
3
C
.2
i
c
m
u
c
o
o
a
06/14 12/14 07/1S 01/16 08/16 03/17 09/17 04/18 10/1S 05/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accjracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
Benzene
ug/L
l l l l l l
BENZENE CONCENTRATION (ug/L)
1
6-Mar-15
0-25
5.2
025
0.25
0.25
2
16-Sep-15
025
3.1
0.25
0.25
0.25
3
4-Mar-16
0 25
2.7
0.25
0.25
0.25
4
26-Sep-16
025
0.867
025
0.25
0.25
5
15-Mar-17
0 25
17
0 25
0.25
0.25
6
19-Sep-17
0 25
14
0.25
0.53
0.25
7
8-Mar-18
0.25
84
0.77
0.68
0.25
8
21-Sep-18
0.25
44
0 25
0.54
0.25
9
26-Mar-19
025
15
0.25
0.57
0.25
10
4-Sep-19
025
35
0 25
0.5
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.00
1.30
0.54
0.42
0.00
Mann-Kendal! Statistic (S):
0
17
3
23
0
Confidence Factor:
45.6%
92.2%
56.9%
97.7%
45.6%
Concentration Trend:
Stable
Prob. Increasing
No Trend
Increasing
Stable
Notes:
1. At least four independent sampling events per well are required tor calculating the Trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accjracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
cis-1,2-DCE
ug/L
I
I
CIS-1,2-DCE CONCENTRATION (ug/L)
1
3/9/2015
025
0 25
14000
0.7
0.25
0 25
0.25
2
9/15/2015
0 25
0.25
2800
1.7
0 25
025
0.25
3
3/3/2016
0 25
0.56
15000
1 4
0 25
0 25
0 25
4
9/26/2016
0 25
0.25
8250
025
0,25
0.25
0.25
5
3/13/2017
0 25
025
6100D
025
0 25
0 25
0 25
6
9/19/2017
0 25
0 25
1500
0 62
0 25
0 25
0 25
7
3/8/2018
0.25
0.25
46000
7.2
0.25
0.25
0.25
8
9/21/2018
025
0.25
3900
5.9
0.25
0.25
0.25
9
3/25/2019
0 25
0.25
11000
8.3
0.25
0.25
0.25
10
9/5/2019
1
0.25
25000
2.2
0.25
0.25
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.35
1.05
1.08
0.00
0.00
0.00
Mann-Kendall Statistic (S):
-5
5
16
0
0
0
Confidence Factor:
63.6%
63.6%
90.7%
45.6%
45.6%
45.6%
Concentration Trend:
No Trend
Stable
No Trend
Prob. Increasing
Stable
Stable
Stable
100000
10000
"at
O
2
*-»
c
0)
u
c
o
o
1000
100
10
1
0.1
-+-
—^
-+-
-H
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
06/14 12/14 07/15 01/16 08/16 03/17 09/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S. Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product; however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ol this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
cia-1,2-DCE
ug/L
l l l l l l
CIA-1.2-DCE CONCENTRATION (ug/L)
1
6-Mar-15
0-25
5.2
025
380
53
2
16-Sep-15
0.25
3.1
0.25
500
43
3
4-Mar-16
0 25
2.7
0.25
230
58
4
26-Sep-16
025
0.867
025
194
131
5
15-Mar-17
0 25
1.7
0 25
110
120
6
19-Sep-17
1.4
14
0.25
74
170
7
8-Mar-18
0.53
84
0.25
61
120
8
21-Sep-18
1.3
44
0 25
110
110
9
26-Mar-19
0.25
15
0.25
72
1.5
10
4-Sep-19
025
35
4.4
640
36
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0,92
1.30
1.97
0.86 | 0.63
Mann-Kendal! Statistic (S):
8
17
9
-18
-4 I
Confidence Factor:
72.9%
92.2%
75.8%
93.4%
60.3% |
Concentration Trend:
No Trend
Prob. Increasing
No Trend
Prob. Decreasing
Stable
Notes:
1. At least four independent sampling events per well are required for calculating the Trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product; however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ol this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
VC
ug/L
I
I
VC CONCENTRATION (ug/L)
1
3/9/2015
1.6
23
830
0 68
0.25
0 25
0.25
2
9/15/2015
15
22
740
3.5
0 25
025
0.25
3
3/3/2016
13
140
950
1 6
0 25
0 25
0 25
4
9/26/2016
2.73
3.24
811
025
0.25
0.25
0.25
5
3/13/2017
29
31
1300
0 25
0 25
0 25
0 25
6
9/19/2017
2
6.3
590
0 74
0 25
0 25
0 25
7
3/8/2018
0.83
62
1400
21
0.25
0.25
0.25
8
9/21/2018
1
6 9
1900
17
0.25
0.25
0.25
9
3/25/2019
0 25
0 25
1600
42
0.25
0.25
0.25
10
9/5/2019
18
9.1
3400
6.2
0.25
0.25
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
1.18
1.53
0.62
1.47
0.00
0.00
0.00
Mann-Kendall Statistic (S):
-13
-3
27
18
0
0
0
Confidence Factor:
85.4%
56.9%
99.2%
93-4%
45.6%
45.6%
45.6%
Concentration Trend:
No Trend
No Trend
Increasing
Prob. Increasing
Stable
Stable
Stable
10000
1000
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
at
3
C
.2
i
c
0
u
c
o
o
0
06/14 12/14 07/15 01/16 08/16 03/17 09/17 04/18 10/18 05/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV «1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has timn exercised in preparing this software product however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accjracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use of this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
2Q~Nov~19
OSL
VC
KKN
ug/L
i i i i i i i
VC CONCENTRATION (ug/L)
1
6-Mar-15
0-25
0 25
025
6.6
0.25
2
16-Sep-15
025
0.25
0.25
2.5
0.25
3
4-Mar-16
0 25
025
0.25
6.6
0.25
4
26-Sep-16
025
0.25
29
1.15
0.25
5
15-Mar-17
0 25
0.25
0 25
3.7
0.25
6
19-Sep-17
0 25
2.4
0.25
3.6
0.25
7
8-Mar-18
0.25
3.1
0.59
3.3
0.25
8
21-Sep-18
0-25
093
1.4
4
0.25
9
26-Mar-19
0.25
0.78
0.25
4.1
0.25
10
4-Sep-19
025
0.5
12
2.4
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.00 Bp 1 2.00 |
0.45
Mann-Kendall Statistic (S):
0 | 17 I 16 |
-6
Confidence Factor:
45.6% I 92.2% I 90.7% I
66.8%
I 45.6% I I
Concentration Trend:
Stable | Prob. Increasing | Prob. Increasing |
Stable
Stable
Notes:
1. At least four independent sampling events per well are required for calculating the Trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product; however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ol this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
PCE
ug/L
I I I I I I I I
PCE CONCENTRATION (ug/L)
1
6-Mar-15
0.74
0 25
025
0.74
0.25
2
16-Sep-15
0.78
0.25
0.25
1.1
0.25
3
4-Mar-16
081
025
0.25
0.93
0.25
4
26-Sep-16
0.583
0.25
025
0.25
0.25
5
15-Mar-17
0.91
0.25
0 25
0.68
0.25
6
19-Sep-17
1
0.25
0.25
0.6
0.25
7
8-Mar-18
1.2
0.25
0.25
0.5
0.25
8
21-Sep-18
1.3
0.66
0 25
1.6
0.25
9
26-Mar-19
0.77
1.1
0.25
1.3
0.25
10
4-Sep-19
094
0.25
0 25
1.5
0.5
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
Mann-Kendall Statistic (S):
0.76
0.00
0.49
0.29
I
21 1
13
0
9
9
IK
Confidence Factor:
96.4%
85,4%
45*6%
75.8%
75.8%
III
Concentration Trend: ¦
No Trend
Stable
No Trend
No Trend
10
U)
3
•I f
c
®
u
c
o
o
0.1
-+-
H-
—H
-f-
-G312B
-G312C
-G313A
-GZ-5M
-GZ-5S
06/14 12/14 07/15 01/16 08/16 03/17 OS/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required tor calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product; however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ol this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
PCE
ug/L
I
I
PCE CONCENTRATION (ug/L)
1
3/9/2015
025
0 25
1.9
0.25
0.25
0.25
0.25
2
9/15/2015
025
0.25
1.2
0.25
0.25
0.25
0.25
3
3/3/2016
0 25
025
1.4
0.25
0.25
0.25
0.25
4
9/26/2016
025
0.25
1 09
0.25
0.25
0.25
0.25
5
3/13/2017
0 25
0.25
12.5
0.25
0.25
0.25
0.25
6
9/19/2017
0 25
0.25
65
0.25
0.25
0.25
0.25
7
3/8/2018
0.25
0.25
2.1
0.25
0.25
0.25
0.25
8
9/21/2018
0.25
025
1.3
0.25
0.25
0.25
0.25
9
3/25/2019
0.25
0.25
12.5
0.25
0.25
0.25
0.25
10
9/5/2019
025
025
25
0.25
0.25
0.25
0.25
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
Mann-Kendall Statistic (S):
Confidence Factor:
Concentration Trend:
1.21
18
93.4%
Prob. Increasing
u>
3
O
V
2
*-*
c
0)
u
c
o
o
-G302A
-G303A
-G304A
-G304B
-G304C
-G311A
-G312A
06/14 12/14 07/1S 01/16
08/16 03/17 09/17 04/18
Sampling Date
10/18 OS/19 12/19
Notes:
1. At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend; < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has timn exercised in preparing litis software product; however, no party, Including without
limitation GSt Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
TCE
"g/L "T
TCE CONCENTRATION (ug/L)
1
3/9/2015
025
0 25
1.1
0 25
1.5
0 25
0.64
2
9/15/2015
0 25
0 25
0.78
0 25
0.75
0 25
0.25
3
3/3/2016
0 25
0 25
25
0.25
0.92
0 25
0.25
4
9/26/2016
0 25
025
0.626
025
11
0.25
0 25
5
3/13/2017
0 25
0.25
125
0 25
1.1
0 25
1.3
6
9/19/2017
0 25
0 25
6 5
0.25
0 71
0 25
0 25
7
3/8/2018
0.25
0.25
2.8
0.25
1.3
0.25
0.74
8
9/21/2018
025
0.25
0.77
0.25
0.76
0.25
0.25
9
3/25/2019
025
025
25
0.54
1.1
0.25
0.52
10
9/5/2019
025
025
50
0.25
0.64
0.25
0.58
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
0.00
0.00
1.30
0.33
0.28
0.00
0.67
Mann-Kendall Statistic (S):
0
0
12
7
-10
0
Confidence Factor:
45.6%
45.6%
83.2%
70.0%
78.4%
45.6%
63.6%
Concentration Trend:
Stable
Stable
No Trend
No Trend
Stable
Stable
No Trend
—G302A
G303A
G304A
—»^G304B
—«— G304C
-*>G311A
—G312A
Sampling Date
1
2
ZO-Nov-19
OSL
KKN
06/14 12/14 07/15 01/16 08/16 03/17 09/17 04/18 10/18 OS/19 12/19
Notes:
At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
i 90% = Probably Increasing or Probably Decreasing < 90% and S»0 = No Trend: < 90%, 330, and COV i 1 = Mo Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans" J.J. Aziz, M. Ling, H.S. Rifai, C J. Newel), and J R. Gonzales,
Ground Water 41(3) 355-367,2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing this software product however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accjracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential. Incidental or other damages resulting from the use of this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
TCE
ug/L
I I I I I I
TCE CONCENTRATION (ug/L)
1
6-Mar-15
0.25
1.5
0 25
77
20
2
16-Sep-15
0.25
1.2
0.25
77
18
3
4-MaM6
0 25
0.85
0 25
42
21
4
26-Sep-16
0 25
025
0 25
26.2
38.4
5
15-Mar-17
025
025
0 25
22
29
6
19-Sep-17
7
1.1
0.25
20
29
7
8-Mar-18
4
9.2
0.25
26
19
8
21-Sep-18
7.7
12
0.25
28
18
9
26-Mar-19
3.2
12
0.25
19
0.25
10
4-Sep-19
1.1
4.6
0.25
78
8.1
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
1.21
1.14
0.00 j 0.61 | 0,54 i
Mann-Kendal! Statistic (S):
^¦19H|8 15
o |-14 |
Confidence Factor:
94.6%
89.2%
45.6% I 87.3% | 92.2% I I
Concentration Trend:
Prob. Increasing
No Trend
Stable Stable [Prob. Decreasing]
ro
o
2
c
0)
u
c
o
o
100
10
0.1
H-
—H
-G312B
-G312C
-G313A
-GZ-5M
-GZ-5S
06/14 12/14 07/15 01/16 08/16 03/17 OS/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required tor calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% «Increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30, and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has timn exercised in preparing this software product; however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use of this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., irww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
GZ-5M - other COCs
ug/L
I I I I I I I
GZ-5M - OTHER COCS CONCENTRATION (ug/L)
1
6-Mar-15
0.62
2
16-Sep-15
8.3
3
4-Mar-16
0.25
4
26-Sep-16
1.2
5
15-Mar-17
0.25
6
19-Sep-17
0.25
7
8-Mar-18
0.76
8
21-Sep-18
0.25
9
26-Mar-19
0.25
10
4-Sep-19
1.1
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
Mann-Kendall Statistic (S):
Confidence Factor:
Concentration Trend:
10
Ul
•$ <1
c
®
u
c
o
o
0.1
1.87
-7
70.0%
No Trend
-t-
-+-
-+-
—i—
-+-
-1,1-OCA
-Acetone
-MIBK
-1.2-DCA
trans-1.2-DCE
06/14 12/14 07/15 01/16 08/16 03/17 OS/17 04/18 10/18 OS/19 12/19
Sampling Date
Notes:
At least four independent sampling events per well are required tor calculating the trend. Methodology is valid for 4 to 40 samples
Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = increasing or Decreasing:
£ 90% = Probably Increasing or Probably Decreasing: < 90% and S»0 = No Trend: < 90%, S30. and COV i 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans", J.J. Aziz, M. Ling, H.S Rifai, C J. Newell, and J R. Gonzales,
Ground Water 41(3) 355-367, 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product: however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall he liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ol this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
G304A - other COCs
ua/L T~
I I I I I
G304A - OTHER COCS CONCENTRATION (ug/L)
1
6-Mar-15
12
2
16-Sep-15
8.3
3
4-Mar-16
2.5
4
26-Sep-16
8.06
5
15-Mar-17
2.5
6
19-Sep-17
2.5
7
8-Mar-18
2.5
8
21-Sep-18
2.5
9
26-Mar-19
2.5
10
4-Sep-19
5.5
11
12
13
14
15
16
17
18
19
20
Coefficient of Variation:
Mann-Kendall Statistic (S):
Confidence Factor:
Concentration Trend:
100
U)
3
•2 10
C
4>
U
C
o
o
Prob. Decreasing|
-H
-t-
-H
-1,1-DCA
-Acetone
MIBK
• 1.2-DCA
-Tetrahydrofuran
06/14 12/14 07/15 01/16
08/16 03/17 OS/17 04/18
Sampling Date
10/18 OS/19 12/19
Notes:
1. At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend; < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing litis software product; however, no party, Including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., ivww.gsi-net.com
-------
GSI MANN-KENDALL TOOLKIT
for Constituent Trend Analysis
20-NOV-19
OSL
KKN
G304A - other COCs
ua/L T~
I I I I I I I
G304A - OTHER COCS CONCENTRATION (ug/L)
1
6-Mar-15
330
98
1200
14
51
9700
6.8
2
16-Sep-15
160
26
200
2.7
12
3400
51
3
4-Mar-16
250
250
1100
25
250
8100
32
4
26-Sep-16
116
116
967
0 25
60.4
7160
25
5
15-Mar-17
125
125
1800
125
330
27000
288
6
19-Sep-17
65
65
160
6 5
65
1800
12.5
7
8-Mar-18
600
600
1700
25
390
15000
6.5
8
21-Sep-18
60
60
270
4.9
20
5000
200
9
26-Mar-19
125
125
600
12.5
125
8600
28
10
4-Sep-19
125
125
680
25
50
11000
12.5
11
25
12
13
14
15
16
17
18
19
20
Coefficient of Variation: I
0.84
1.04
0.68
0.74
Mann-Kendall
Confk
Statistic (S):
-14
8
-5
7
fence Factor:
87.3% I 72.9%
63.6%
70.0%
Concentration Trend: j
Stable
No Trend
Stable
No Trend
No Trend
No Trend
No Trend
100006
-1.1-DCA
-Acetone
-MIBK
-1.2-DCA
-Tetrahydrofuran
-Toluene
trans-1,2-DCE
06/14 12/14 07/15 01/16
08/16 03/17 09/17
Sampling Date
04/1S 10/18 05/19 12/19
Notes:
1. At least four independent sampling events per well are required for calculating the Trend. Methodology is valid for 4 to 40 samples
2. Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing:
a 90% = Probably Increasing or Probably Decreasing; < 90% and S»0 = No Trend: < 90%, 330, and COV a 1 = No Trend: < 90% and COV < 1 = Stable.
Methodology based on "MAROS: A Decision Support System tor Optimizing Monitoring Plans" J, J. Aziz, M. Ling, H.S Rifai, CJ, Newell, and JR. Gonzales,
Ground Water 41(3) 355-367 2003,
DISCLAIMER: The GSI Mann-Kendall Toolkit Is available "as is". Considerable care has t>mn exercised in preparing this software product; however, no party, including without
limitation GSI Environmental inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall tie liable tor any direct, indirect, consequential, incidental or other damages resulting from the use ot this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental inc., disclaims any responsibility or obligation to update the information contained herein,
GSI Environmental Inc., irww.gsi-net.com
-------
APPENDIX D
-------
Chlorinated Ethenes - G302A
d 150
Sb
=5
o
¦<
o
©
©
O
o
o
o
o
o
o
o
»—t
»—i
1—s
f-H
*—«
»
>-,
>->
£**>
;>>
£**>
GJ
cs
03
cd
KJ
a
co
«
c3
ec
C3
-------
Chlorinated Ethenes - G303A
—vc
—cDCE
-------
Chlorinated Ethenes - G303A
vc
—cDCE
K Welev
-------
Benzene - G304A
¦ Benzene
-------
Toluene, Ethylbenzene, Total Xylenes, and Total BTEX - G304A
60000
50000
40000
% 30000
2
20000
10000
Toluene
Ethylbenzene
Total Xylenes
Total BTEX
o
<3>>
I
c
3
O
o
I
c
3
tN
"<3-
\C,
r-
00
OS
O
—i
C4
f—
—1
SO
—1
00
On
r
O
©
cp
O
o
Cp
o
o
o
o
¦1—<
T-i
i
»—<
»—<
*—•
—1
'—s
—i
•—j
—i
¦—i
i—»
'—i
•—1
~—J
•—»
>—>
-------
Chlorinated Ethenes - G304A
90000
80000
70000
60000
50000
1=40000
30000
20000
10000
0 *
x m * * *—ft-
~—TCE-EQ
¦—PCE
TCE
cDCE
*-VC
On
O
l—i
»—»
»—J
*—»
•—>
-------
Chlorinated Ethenes - G304A
90000
—>
s
>—>
1—1
80000
70000
60000
50000
oo
40000
30000
20000
10000
-------
Ketones - G304A
8000
7000
6000
5000
t—I
tsjo 4000
3000
2000
1000
0
MEK
-MIBK
Acetone
v©
o
r-
o
00
o
c\
o
o
CN
fO
OG
o
5—l
Jun-
Jun-
I
-------
-------
-------
-------
Chlorinated Ethenes - GZ-5S
—TCE
—cDC'E
-------
Chlorinated Ethenes - G312A
—TCE
-------
Chlorinated Ethenes - G312B
rn
ITi
'O
r-
CO
On
o
<—1
es
*£>
r~~
00
Os
o
o
o
o
©
©
o
—1
1—^
>—i
o
o
o
o
o
o
O
o
U
u
u
o
6
u
o
-------
Chlorinated Ethenes - G312C
z ? ^:r'
o v
1% n n ri r**i ri
m
©
i
¦*—>
u
o
t
o
*-
u
O
m
o
~L
o
o
VO
o
I
o
o
r-
o
I
+*
o
O
O
00
a
O
On
o
—•—TCE
—¦—cDCE
VC
-------
-------
APPENDIX E
-------
LANDFILL INSPECTION REPORT
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
SEPTEMBER 2019
1.0 INTRODUCTION
On September 4, 2019, Nobis Engineering, Inc. (Nobis) performed oversight of the Cap
Effectiveness groundwater sampling event and performed cursory observations of the key
landfill components at the Old Southington Landfill Superfund Site (Site), in Southing ton,
Connecticut. This report was prepared for the U.S. Environmental Protection Agency (EPA)
under Task Order No. 0017-RX-ME-0158 of Remedial Action Contract No. EP-S1-06-03. The
field activities were performed by Loureiro Engineering Associates, Inc. (LEA) of Plainville,
Connecticut, contractor for the Performing Settling Defendants (PSDs). The field sampling
activities were observed for compliance with the requirements of the Remedial Design Project
Operations Plan, dated November 2010 and revised June 2011. Nobis' representative, Mr.
James Harrington, observed the sampling activities performed by two LEA representatives.
2.0 WELL GAUGING ACTIVITIES
The water levels in groundwater monitoring wells were gauged using an electronic water level
meter on September 4, 2014 while well purging and sampling were being performed. The depth
to water in each well was measured to the nearest 0.01-foot and recorded on log sheets. This
information will be used to determine hydraulic gradient and groundwater flow direction for the
September 2019 sampling round. This activity was not directly observed by the Nobis
representative.
3.0 GROUNDWATER SAMPLING OVERSIGHT
Nobis observed LEA sampling activities at the G-312 A, B, and C monitoring wells. A total of 12
groundwater monitoring wells were scheduled to be sampled by LEA during this event. Nobis
was present for sample collection at the above-noted monitoring well. Details of the observed
sampling activities are described below in Sections 3.1 through 3.4. Photographs of the
sampling setups are included in Attachment B.
1
Nobis Engineering, Inc.
-------
3.1
Instrument, Equipment, and Weil Inspection
Groundwater parameters (pH, temperature, specific conductivity, dissolved oxygen, and
oxidation reduction potential) were monitored using a YSl 660 multi-meter (YSI). Instruments
were calibrated at LEA's shop prior to coming to the field with results of the calibrations
recorded on calibration log sheets. LEA reported that instrument calibration checks are
performed following the completion of daily sampling activities.
Groundwater turbidity was measured using a Hach brand turbidity meter using water collected
from a T-adaptor prior to the flow-through cell. The calibration procedure for the turbidity meters
is equivalent to methods used for the YSI meters.
The monitoring equipment used by LEA appeared to be in good condition and functioning
properly during well purging activities.
3.2 Well Purging and Groundwater Quality Parameter Monitoring
All monitoring wells observed on September 4, 2019 were purged using dedicated bladder
pumps and tubing. The LEA samplers calculated flow rates using a graduated cylinder and a
timer. LEA recorded water levels during the purging to monitor drawdown.
After a steady flow rate was established, tubing was attached to the flow-through cell, and the
YSI was used to monitor water quality parameter readings in the flow-through cell every 10
minutes. When monitored water quality parameters indicated the well was near stabilization,
readings were recorded every 5 minutes. LEA samplers recorded a minimum of 3 readings at 5-
minute intervals prior to sample collection. All YSI readings were recorded on log sheets.
Turbidity samples were collected using a T-adapter to fill the sample vial. Purge water was
collected in 5-gallon totes with secondary containment tubs throughout the well purging process.
3.3 Sample Collection, Handling, and Documentation
Stabilization of the groundwater parameters was achieved within the recommended time
indicated by the EPA Region 1 Low Stress Guidelines SOP for the monitoring well observed.
After stabilization was achieved, LEA collected samples by removing the inlet line to the flow-
2
Nobis Engineering, Inc.
-------
through cell and filling the three sample vials. VOC containers were pre-preserved with
hydrochloric acid. After samples were collected, they were placed in a cooler with ice.
No discrepancies were observed during sampling at this well.
Following the completion of sample collection, the dedicated tubing was placed back into the
monitoring well and the well was secured. According to the LEA sampler, the groundwater
samples remained in the coolers until the end of the work day and were transported to the LEA
construction office on Site for sample packing and shipping. The sample information (e.g., date,
collection time, and well identification) was recorded on a tracking report chain-of-custody
(COC) form.
3.4 Waste Containerization and Decontamination
Groundwater purge water was collected in 5-gallon totes during well purging activities. When
sampling activities were completed at a monitoring well, covers were placed on the 5-gaIIon
totes. The filled totes were then reportedly transported to the purge water storage area on the
Site and the contents transferred to 55-gallon drums. The purge water storage area is located
within the fenced landfill area along the southern side of the Site access road. Nobis did not
observe purge water transport. A photo of the purge water storage drum is included in
Attachment A.
Nobis did not observe decontamination of sampling equipment.
4.0 CURSORY OBSERVATIONS
On September 4, 2019, Nobis performed cursory observations of various landfill components;
photographs of the components are presented in Attachment A. As previously discussed with
the EPA Remedial Project Manager, Nobis was requested to perform cursory observations of
the condition of the landfill components in conjunction with observing the field sampling
activities. These observations do not constitute a formal inspection of the landfill.
3
Nobis Engineering, Inc.
-------
4.1
Landfill Cover
Overall, the landfill cover appears to be in good condition. The vegetation is healthy and well
maintained. Nobis did not observe any evidence of undesired vegetation or excessive growth.
Nobis did not observe any evidence of vandalism (i.e., ruts/tire tracks) on the cover. No holes or
other evidence of digging or foraging animals was observed. There was an area of bulging
observed on the southern portion of the landfill, approximately 45 feet east of GV-2. The
bulging encompasses an area of approximately 10 feet in diameter, elevated about 8 inches
above the surface of the surrounding cover.
4.2 Site Security Fence
Based on Nobis' limited observations, the security fence appears to be in good condition. There
are no warning signs posted. Nobis did not observe any evidence of vandalism or unauthorized
access to the Site through the fence. Excessive overgrowth of vegetation was observed along
the southern perimeter. Damage to fencepost was observed opposite the entrance to Chuck &
Eddie's Used Auto Parts.
4.3 Drainage Swales
The southern drainage swale and the gabion mats were in excellent condition with little to no
vegetation growing in the mats. The central drainage swale showed no evidence of erosion or a
wet area as had been seen in previous inspections, the result of low precipitation accumulation.
The west swale on the west side of Old Turnpike Road was not inspected. At the downstream
side of the three 24-inch culverts under the access road, some tree pruning has occurred, and
branches and debris were discarded in the area in front of the culverts, which may cause
blockage. The Black Pond discharge swale was very overgrown with low-growing vegetation.
The drain at the western end of the drainage swale was becoming overgrown. While some
drainage is occurring, it is being impeded by vegetative growth and standing water was
observed within the swale on both sides of Old Turnpike Road.
4
Nobis Engineering, Inc.
-------
4.4 Gas Venting System
Nobis did not fully inspect the gas vents. Based on limited observations, the gas vents
appeared to be in good condition. The vents were in an upright position, recently painted, and
there was no evidence of vandalism.
4.5 Settlement Monitoring
There was no evidence of significant subsidence observed by Nobis on the day of the site walk,
however, no settlement markers were surveyed.
4.6 Groundwater Monitoring System
Nobis only observed monitoring well cluster G-312, and it appeared to be in good condition.
Well casings and covers were in acceptable condition. Wells appeared undisturbed. Nobis did
not observe monitoring wells G-312-A, B» and C being opened or closed.
5.0 CONCLUSIONS AND RECOMMENDATIONS
In general, sampling procedures followed the EPA-approved Work Plan which is consistent with
the EPA Region 1 Low Stress Guidelines SOP.
The following recommendations should be considered for future sampling events:
• Reduce vegetative growth in the swale from Black Pond.
• Evaluate bulging near GV-02 and determine if repair or maintenance is required to
prevent further damage to landfill cap.
• Remove discarded trimmings from outlet of culvert in the Central Drainage Swale.
• Remove excessive vegetation from southern perimeter fence and GV-0 and GV-01
enclosures.
• Repair damaged fencepost opposite of entrance to Chuck and Eddie's Used Auto
Parts property.
5
Nobis Engineering, Inc.
-------
Photographs of Site Inspection, Old Southington Landfill, September 4,2019
Photo 1 - Bulging near GV-02.
Photo 1 - Bulging near GV-02.
Photo 3 — Bulging near GV-02.
Photo 4-Access Road settlement/cracking.
-------
Photographs of Site Inspection, Old Southington Landfill, September 4, 2019
"
Photo 5 - Excessive vegetation in GV-0 enclosure.
Photo 6 - Fencepost damage opposite entrance to Chuck & Eddie's.
Photo 7 - Excessive vegetation, southern perimeter fence.
Photo 8 - Gabion mat damage, southern portion of landfill.
-------
Photographs of Site Inspection, Old Southington Landfill, September 4,2019
Photo 9- Gabion mat damage, southern portion of landfill.
Photo 10 -Discarded tree trimmings at culvert outlet, southern portion of landfill near
storage facility.
Photo 11 - Standing water and excessive vegetation in Black Pond Swale.
Photo 12- Standing water and excessive vegetation in Black Pond Swale, downstream of
culvert under Old Turnpike Road
-------
APPENDIX G
SITE INSPECTIONS
-------
nobis
EPA Region 1 RAC 2 Contract No. EP-S1-06-03
December 30, 2019
Nobis Project No. 80017
| Via Electronic Submittal
U.S. Environmental Protection Agency, Region 1
Attention: Ms. Almerinda Silva, Task Order Project Officer
5 Post Office Square, Suite 100
Boston, Massachusetts 02109-3919
Subject; Trip Report, September 2019 Groundwater Sampling and Landfill Inspection
Old Southington Landfill Superfund Site, Southington, Connecticut
Long-Term Response Action Oversight
Task Order No. 0017-RX-ME-0158
Dear Ms. Silva:
Enclosed for EPA's review is the Trip Report documenting oversight activities performed by Nobis
Engineering, Inc. at the Old Southington Landfill Superfund Site located in Southington,
Connecticut on September 4, 2019.
Should you have any questions or comments, please contact me at (978) 703-6003, or
chul@nobiseng.com.
Sincerely,
NOBIS ENGINEERING, INC.
Dicifa"v signed by LiyangChu
, . DN; C=US,
I I \/0 nril h I I E--Schu@nobis-group.corn,
I— 1 ¥ QI ly w I !U OU=NobisGroup, CN-LiyangChu
Date 2019.12,30 13:35:26-05*00'
Liyang Chu
Senior Project Manager
Attachment
c: File 80017/MA (w/att.)
J. Harrington (w/att.)
CUent-Focused, Employee-Owned Nobis Engineering, int.
, . 585 Middlesex Street
www.twbis~group.cotn Low
-------
LANDFILL INSPECTION REPORT
OLD SOUTHINGTON LANDFILL SUPERFUND SITE
SOUTHINGTON, CONNECTICUT
SEPTEMBER 2019
1.0 INTRODUCTION
On September 4, 2019, Nobis Engineering, Inc. (Nobis) performed oversight of the Cap
Effectiveness groundwater sampling event and performed cursory observations of the key
landfill components at the Old Southington Landfill Superfund Site (Site), in Southing ton,
Connecticut. This report was prepared for the U.S. Environmental Protection Agency (EPA)
under Task Order No. 0017-RX-ME-0158 of Remedial Action Contract No. EP-S1-06-03. The
field activities were performed by Loureiro Engineering Associates, Inc. (LEA) of Plainville,
Connecticut, contractor for the Performing Settling Defendants (PSDs). The field sampling
activities were observed for compliance with the requirements of the Remedial Design Project
Operations Plan, dated November 2010 and revised June 2011. Nobis' representative, Mr.
James Harrington, observed the sampling activities performed by two LEA representatives.
2.0 WELL GAUGING ACTIVITIES
The water levels in groundwater monitoring wells were gauged using an electronic water level
meter on September 4, 2014 while well purging and sampling were being performed. The depth
to water in each well was measured to the nearest 0.01-foot and recorded on log sheets. This
information will be used to determine hydraulic gradient and groundwater flow direction for the
September 2019 sampling round. This activity was not directly observed by the Nobis
representative.
3.0 GROUNDWATER SAMPLING OVERSIGHT
Nobis observed LEA sampling activities at the G-312 A, B, and C monitoring wells. A total of 12
groundwater monitoring wells were scheduled to be sampled by LEA during this event. Nobis
was present for sample collection at the above-noted monitoring well. Details of the observed
sampling activities are described below in Sections 3.1 through 3.4. Photographs of the
sampling setups are included in Attachment B.
1
Nobis Engineering, Inc.
-------
3.1
Instrument, Equipment, and Weil Inspection
Groundwater parameters (pH, temperature, specific conductivity, dissolved oxygen, and
oxidation reduction potential) were monitored using a YSl 660 multi-meter (YSI). Instruments
were calibrated at LEA's shop prior to coming to the field with results of the calibrations
recorded on calibration log sheets. LEA reported that instrument calibration checks are
performed following the completion of daily sampling activities.
Groundwater turbidity was measured using a Hach brand turbidity meter using water collected
from a T-adaptor prior to the flow-through cell. The calibration procedure for the turbidity meters
is equivalent to methods used for the YSI meters.
The monitoring equipment used by LEA appeared to be in good condition and functioning
properly during well purging activities.
3.2 Well Purging and Groundwater Quality Parameter Monitoring
All monitoring wells observed on September 4, 2019 were purged using dedicated bladder
pumps and tubing. The LEA samplers calculated flow rates using a graduated cylinder and a
timer. LEA recorded water levels during the purging to monitor drawdown.
After a steady flow rate was established, tubing was attached to the flow-through cell, and the
YSI was used to monitor water quality parameter readings in the flow-through cell every 10
minutes. When monitored water quality parameters indicated the well was near stabilization,
readings were recorded every 5 minutes. LEA samplers recorded a minimum of 3 readings at 5-
minute intervals prior to sample collection. All YSI readings were recorded on log sheets.
Turbidity samples were collected using a T-adapter to fill the sample vial. Purge water was
collected in 5-gallon totes with secondary containment tubs throughout the well purging process.
3.3 Sample Collection, Handling, and Documentation
Stabilization of the groundwater parameters was achieved within the recommended time
indicated by the EPA Region 1 Low Stress Guidelines SOP for the monitoring well observed.
After stabilization was achieved, LEA collected samples by removing the inlet line to the flow-
2
Nobis Engineering, Inc.
-------
through cell and filling the three sample vials. VOC containers were pre-preserved with
hydrochloric acid. After samples were collected, they were placed in a cooler with ice.
No discrepancies were observed during sampling at this well.
Following the completion of sample collection, the dedicated tubing was placed back into the
monitoring well and the well was secured. According to the LEA sampler, the groundwater
samples remained in the coolers until the end of the work day and were transported to the LEA
construction office on Site for sample packing and shipping. The sample information (e.g., date,
collection time, and well identification) was recorded on a tracking report chain-of-custody
(COC) form.
3.4 Waste Containerization and Decontamination
Groundwater purge water was collected in 5-gallon totes during well purging activities. When
sampling activities were completed at a monitoring well, covers were placed on the 5-gallon
totes. The filled totes were then reportedly transported to the purge water storage area on the
Site and the contents transferred to 55-gallon drums. The purge water storage area is located
within the fenced landfill area along the southern side of the Site access road. Nobis did not
observe purge water transport. A photo of the purge water storage drum is included in
Attachment A.
Nobis did not observe decontamination of sampling equipment.
4.0 CURSORY OBSERVATIONS
On September 4, 2019, Nobis performed cursory observations of various landfill components;
photographs of the components are presented in Attachment A. As previously discussed with
the EPA Remedial Project Manager, Nobis was requested to perform cursory observations of
the condition of the landfill components in conjunction with observing the field sampling
activities. These observations do not constitute a formal inspection of the landfill.
3
Nobis Engineering, Inc.
-------
4.1
Landfill Cover
Overall, the landfill cover appears to be in good condition. The vegetation is healthy and well
maintained. Nobis did not observe any evidence of undesired vegetation or excessive growth.
Nobis did not observe any evidence of vandalism (i.e., ruts/tire tracks) on the cover. No holes or
other evidence of digging or foraging animals was observed. There was an area of bulging
observed on the southern portion of the landfill, approximately 45 feet east of GV-2. The
bulging encompasses an area of approximately 10 feet in diameter, elevated about 8 inches
above the surface of the surrounding cover.
4.2 Site Security Fence
Based on Nobis' limited observations, the security fence appears to be in good condition. There
are no warning signs posted. Nobis did not observe any evidence of vandalism or unauthorized
access to the Site through the fence. Excessive overgrowth of vegetation was observed along
the southern perimeter. Damage to fencepost was observed opposite the entrance to Chuck &
Eddie's Used Auto Parts.
4.3 Drainage Swales
The southern drainage swale and the gabion mats were in excellent condition with little to no
vegetation growing in the mats. The central drainage swale showed no evidence of erosion or a
wet area as had been seen in previous inspections, the result of low precipitation accumulation.
The west swale on the west side of Old Turnpike Road was not inspected. At the downstream
side of the three 24-inch culverts under the access road, some tree pruning has occurred, and
branches and debris were discarded in the area in front of the culverts, which may cause
blockage. The Black Pond discharge swale was very overgrown with low-growing vegetation.
The drain at the western end of the drainage swale was becoming overgrown. While some
drainage is occurring, it is being impeded by vegetative growth and standing water was
observed within the swale on both sides of Old Turnpike Road.
4
Nobis Engineering, Inc.
-------
4.4 Gas Venting System
Nobis did not fully inspect the gas vents. Based on limited observations, the gas vents
appeared to be in good condition. The vents were in an upright position, recently painted, and
there was no evidence of vandalism.
4.5 Settlement Monitoring
There was no evidence of significant subsidence observed by Nobis on the day of the site walk,
however, no settlement markers were surveyed.
4.6 Groundwater Monitoring System
Nobis only observed monitoring well cluster G-312, and it appeared to be in good condition.
Well casings and covers were in acceptable condition. Wells appeared undisturbed. Nobis did
not observe monitoring wells G-312-A, B, and C being opened or closed.
5.0 CONCLUSIONS AND RECOMMENDATIONS
In general, sampling procedures followed the EPA-approved Work Plan which is consistent with
the EPA Region 1 Low Stress Guidelines SOP.
The following recommendations should be considered for future sampling events:
• Reduce vegetative growth in the swale from Black Pond.
• Evaluate bulging near GV-02 and determine if repair or maintenance is required to
prevent further damage to landfill cap.
• Remove discarded trimmings from outlet of culvert in the Central Drainage Swale.
• Remove excessive vegetation from southern perimeter fence and GV-0 and GV-01
enclosures.
• Repair damaged fencepost opposite of entrance to Chuck and Eddie's Used Auto
Parts property.
5
Nobis Engineering, Inc.
-------
ATTACHMENT A
-------
FORM 2 - LANDFILL COMPONENTS CHECKLIST
OLD SOUTHINGTON LANDFILL, SOUTHINGTON, CT
SEPTEMBER 4, 2019
Page 1
COMPONENT
OBSERVATIONS/COMMENTS
OU1
SITE COVER: NORTHERN PORTION OF LANDFILL CAP
VEGETATIVE COVER
(COVERAGE, DISTRESS)
Appears to be well vegetated and maintained (mowed).
PRESENCE OF DEEP-ROOTED
VEGETATION
None noted.
BURROWING ANIMALS
None noted.
HOLES (EXTENT/DEPTH)
None noted.
EROSION (EXTENT/DEPTH)
None noted.
LOCALIZED SETTLEMENT /
SLUMPING
None noted.
PONDING OF
WATER/DRAINAGE
None noted.
SEEPAGE
None noted.
SLOUGHING
None noted.
VANDALISM
None noted.
OTHER OBSERVATIONS
Bulging observed approximately 45 feet east of GV-2. The bulging
encompasses an area of approximately 10 feet in diameter, elevated
about 8 inches above the surface of the surrounding cover, (Photos 1-3)
SITE COVER: SOUTHERN PORTION OF LANDFILL CAP
VEGETATIVE COVER
(COVERAGE, DISTRESS)
Appears to be well vegetated and maintained (mowed).
PRESENCE OF DEEP-ROOTED
VEGETATION
None noted.
BURROWING ANIMALS
None noted.
HOLES
None noted.
EROSION
None noted.
LOCALIZED SETTLEMENT
/SLUMPING
None noted.
PONDING OF
WATER/DRAINAGE
None noted.
SEEPAGE
None noted.
SLOUGHING
None noted.
VANDALISM
None noted.
OTHER OBSERVATIONS
-------
FORM 2 - LANDFILL COMPONENTS CHECKLIST
OLD SOUTHINGTON LANDFILL, SOUTHINGTON, CT
SEPTEMBER 4, 2019
Page 2
COMPONENT
OBSERVATIONS/COMMENTS
LCI ACCESS ROAD
EROSION
None noted.
POTHOLES/CRACKING
Cracking observed at low area near entrance to storage facility. (Photo 4)
LOCALIZED SETTLEMENT
Settlement observed in low area near entrance to storage facility. (Photo
4)
WINTER ACCESS
None noted.
OTHER OBSERVATIONS
None noted.
GAS VENTS (See CRA Dwg. C-07 for GV-0 to GV-12 Locations)
GAS FLOW (AUDIBLE/VISUAL)
None Noted.
CORROSION OR STRUCTURAL
DAMAGE
None noted.
SCREEN INTACT/BLOCKAGE
None noted.
SMOKE EMISSION
None noted.
UNCLEAR IDENTIFICATION
None noted.
PEELING PAINT
None noted.
OTHER OBSERVATIONS
Fenced areas around GV-0 and GV-01 are heavily vegetated. (Photo 5)
SECURITY: PERIMETER FENCE
CORROSION OR STRUCTURAL
DAMAGE TO PERIMETER
FENCE SUPPORT POSTS
Damage to fencepost observed opposite the entrance to Chuck & Eddie's
Used Autoparts. Encroaching vegetation noted in a few locations along
the western and southern perimeters that will need to be trimmed back.
(Photos 6-7).
CORROSION DAMAGE FENCE
FABRIC
None noted.
SECURITY: GATES AND LOCKS
CORROSION, VISIBILITY,
DAMAGE TO GATE, HINGES
None noted.
LOCKS STICKING OR
CORRODING
None noted.
OTHER OBSERVATIONS
-------
FORM 2 - LANDFILL COMPONENTS CHECKLIST
OLD SOUTHINGTON LANDFILL, SOUTHINGTON, CT
SEPTEMBER 4, 2019
Page 3
COMPONENT
OBSERVATIONS/COMMENTS
SOUTH DRAINAGE SWALE (See CRA Dwg. C-04 for Swale Location)
SEDIMENT BUILD-UP/DEPTH
None noted. Maintained regularly.
RIP-RAP
Some of the steel mesh overlying the rip-rap stone is raised, poses
potential trip hazard. The mesh needs should be repaired.
EROSION
None noted.
SETTLEMENT
None noted.
DRAINAGE
None noted.
CULVERTS
None noted.
OTHER OBSERVATIONS
CENTRAL DRAINAGE SWALE (See CRA Dwg. C-04 for Swale Location)
SEDIMENT BUILDUP/DEPTH
None noted. Maintained regularly.
RIP-RAP
None noted.
EROSION
None noted.
SETTLEMENT
None noted.
DRAINAGE
None noted.
CULVERTS
None noted.
OTHER OBSERVATIONS
Tree pruning observed in the area of the three 24-inch culvert outlets
near the storage facility. Cuttings discarded in place potentially causing
some flow restriction.
WEST DRAINAGE SWALE (See CRA Dwg. C-04 for Swale Location)
SEDIMENT BUILDUP/DEPTH
None noted.
RIP-RAP
None noted.
EROSION
None noted.
SETTLEMENT
None noted.
DRAINAGE
N one noted.
CULVERTS
None noted.
OTHER OBSERVATIONS
-------
FORM 2 - LANDFILL COMPONENTS CHECKLIST
OLD SOUTHINGTON LANDFILL, SOUTHINGTON, CT
SEPTEMBER 4, 2019
Page 4
COMPONENT
OBSERVATIONS/COMMENTS
BLACK POND DRAINAGE SWALE (See CRA Dwg. C-04 for Swale Location)
SEDIMENT BUILDUP/DEPTH
None noted.
RIP-RAP
None noted.
EROSION
None noted.
SETTLEMENT
None noted.
DRAINAGE
Ponded water at culvert inlet. Runoff was observed to drain into ponded
area. Accumulated vegetative matter appears to limit drainage into the
culvert. Both sides of culvert should be cleared to improve drainage.
CULVERTS
Not observed.
OTHER OBSERVATIONS
SUBSURFACE DRAIN PIPES (See CRA Dwg. C-08 for Drain Pipe Outlet Locations)
Two Drain Pipes Outlets
Condition (e.g., blockage, signs of
flow)
Not observed as these were not visible from Black Pond perimeter.
Drain Pipe Outlet (at TOC 05)
(e.g., blockage, signs of flow)
Same as above.
Drain Pipe Outlet (at TOC 06)
(e.g., blockage, signs of flow)
Same as above.
Drain Pipe Outlet at Black Pond
Discharge Swale
(e.g., blockage, signs of flow)
Same as above.
MONITORING WEL
ONLY G-312 A, B, C obse
LS (On C&E's Property, observed on September 4, 2019)
rved, as they were being sampled at the time of the inspection
WELL CASING 1 CAP / LOCK
CONDITIONS
No problems identified.
PVC RISERS
No problems identified.
CONCRETE PAD
No problems identified.
FROST HEAVES
No problems identified.
VEGETATION (CLEARED)
No problems identified.
UNCLEAR IDENTIFICATION
No problems identified.
CORROSION
No problems identified.
PEELING PAINT
No problems identified.
-------
FORM 2 - LANDFILL COMPONENTS CHECKLIST
OLD SOUTHINGTON LANDFILL, SOUTHINGTON, CT
SEPTEMBER 4, 2019
Page 5
COMPONENT
OBSERVATIONS/COMMENTS
VANDALISM
No problems identified.
OTHER OBSERVATIONS
GAS BARRIER TRENCH at NORTHERN PERIMETER OF LANDFILL (see Fig. 2)
TRENCH CONDITION
No problems observed.
VERTICAL LINER VISIBLE OR
EXPOSED
None noted.
FILL SETTLEMENT
None noted.
EROSION
None noted.
OTHER OBSERVATIONS
OU2 VAPOR BARRIER under C&E BUILDING 2 (FABRIC STRUCTURE BUILDING)
CONCRETE SLAB CONDITION
(CRACKS, HOLES, ETC.)
Not observed.
PENETRATIONS
Not observed
SIDEWALL OR FOOTING
SETTLEMENT
Not observed.
OTHER OBSERVATIONS
Not observed
Note: This Checklist is based, in part, on items/components identified in the OSL Landfill Site Features Inspection Log and
additional components installed after the completion of the OU1 remedy.
-------
ATTACHMENTB
-------
Photographs of Site Inspection, Old Southington Landfill, September 4,2019
A Jt''-
Photo 1 - Bulging near GV-02.
. . .
vW- . , •
Photo 3 — Bulging near GV-02.
Photo 1 - Bulging near GV-02.
Photo 4-Access Road settlement/cracking.
-------
Photographs of Site Inspection, Old Southington Landfill, September 4, 2019
I ^
Photo 5 - Excessive vegetation in 6V-0 enclosure.
Photo 7 - Excessive vegetation, southern perimeter fence.
Photo 6 - Fencepost damage opposite entrance to Chuck S Eddie's.
Photo 8 - Gabion mat damage, southern portion of landfill.
-------
Photographs of Site Inspection, Old Southington Landfill, September 4, 2019
Photo 10 -Discorded tree trimmings at culvert outlet, southern portion of landfill near
storage facility.
Photo 11 - Standing water and excessive vegetation in Black Pond Swale.
Photo 12- Standing water and excessive vegetation in Black Pond Swale, downstream of
culvert under Old Turnpike Road
-------
Lbureiro
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Wrr«to • Facility Sim s>, « L'ix >„
-------
US EPA
February 3, 2020
Page 2 of 2
finu H'Vi nq » Li^is.vrt'cniin • C.S-iNo * C.icrqv
WaMf> * FikiN> S'Mvkps • Labutafoiv
likely punctured the upper vapor barrier, and the United States Environmental Protection Agency
(US EPA) required that the baseplates of the hydraulic lifts be sealed with caulk. Loureiro
completed the sealing of the baseplates in June 2018. The approximate locations of the hydraulic
lifts in Building 2 on the C&E property is depicted on Figure 4. Biennial inspection of the seals
of the hydraulic lift baseplates and Building 2 (for any new penetrations of the concrete, condition
of the concrete floor, etc.) are also required as part of the long-term monitoring for the Site. This
letter documents the inspections completed by Loureiro of the two properties with respect to the
ELURs, and the inspection of the Quonset hut style building (Building 2) on the C&E property.
Site Inspections
Loureiro personnel visited the two offsite properties on September 13, 2019 to perform the
inspection of the two properties and Building 2 at the C&E property. No new buildings, or
evidence of new buildings being constructed, were observed during the Site visit. Loureiro
examined the bolts and base plates of the hydraulic lifts in Building 2 on the C&E property and
found the caulking to be in good condition. Concrete staining was observed at two locations in
Building 2, one along the western portion in the center of the building and another around one of
the hydraulic lifts. One crack in the concrete was observed in the eastern portion of the building,
but appeared to be a surficial crack and would not have affected the underlying vapor barrier.
Photographic documentation of the biennial inspection is provided in Attachment 1, and a copy
of the inspection forms are provided in Attachment 2.
Building Department Records
Loureiro confirmed on the Town of Southington's Building Department website that no new
construction was proposed or scheduled at either of the two properties. Two permits were
identified for the Radio Station property (an electrical permit and a cell tower/satellite permit).
Both permits were in regards to removing and replacing the three existing antennas on the property,
and do not constitute the construction of a new occupied building. Copies of the building permits
are provided in Attachment 3.
Conclusions
Based on the findings of the site inspections and Building Department records review, no items
were identified that would indicate a potential issue with the integrity of the ELURs that have been
recorded on the Radio Station and Chuck & Eddies properties. No follow up work is
recommended, and the next ELUR inspection will be scheduled for 2021.
Loureiro
-------
US EPA
February 3, 2020
Page 3 of 2
Loureiro
tr.u hern q • i * Li k\S • C.*> iq\
VYn^to * Fjcihn Sctvicr-s • Lnt'OMtoiy
If you have any questions or would like to discuss this report, please contact me or Dave Fiereck
at (860) 747-6181.
Sincerely,
LOUREIRO ENGINEERING ASSOCIATES, INC.
Joseph T. Trzaski, L.E.P.
Senior Project Scientist
Attachments
cc: Steve Gaura (CT DEEP)
Sharee Rusnek (Connecticut Department of Public Health)
Liyang Chu (Nobis Engineering)
Martin Booher (Baker & Hostetler, LLP)
David Clymer (United Technologies Corporation)
David Piatt (United Technologies Corporation)
Nathan Brodeur (Goodwin Proctor LLP)
Dan Kirk (Shell Oil Products US)
William Hvidsten (Aerojet Rockeydyne)
Scott Goulart (Aerojet Rockeydyne)
-------
FIGURES
-------
T7"—
) Hol.comb
/&mm
RCHANGfgX^
¦CHUCK & EDDIES
PROPERTY
¦RADIO STATION
PROPERTY
MAP REFERENCE:
PORTION OF 7.5 MINUTE SERIES MAP FOR THE
SOUTHINGTON, CT QUADRANGLE DATED 1968
PHOTO REVISED 1992, N.G.V.D.1929,
TAKEN FROM TOPO! CD. VERSION 1.2.4
1998 WILDFLOWER PRODUCTIONS.
¦OLD SOUTHINGTON
LANDFILL SITE
0 500 1000 1500
SCALE IN FEET (APPROX.)
Loureiro
Engineering • Construction • EH&S • Energy
Waste • Facility Services • Laboratory
Loureiro Engineering Associates, Inc.
100 Northwest Drive • Plainville, Connecticut 06062
Phone: 860-747-6181 • Fax: 860-747-8822
An Employee Owned Company • www.Loureiro.com
©Loureiro Engineering Associates, Inc.
All rights reserved 2020
BIENNIAL INSPECTION OF ELURs
OLD SOUTHINGTON LANDFILL SITE, SOUTHINGTON, CONNECTICUT
SITE LOCATION MAP
PREPARED FOR:
PERFORMING SETTLING DEFENDANTS
OLD SOUTHINGTON LANDFILL PROJECT
SCALE
1" = lOOO"
COMM. NO.
61SL902
DATE
01/21/2020
FIGURE 1
-------
VICINITY MAP
Scale: 1"=40'
LEGEND
Fence Chain Link
Property Line
Road
Tree Line
Water Course
SCHEDULE OF
ENVIRONMENTAL LAND USE RESTRICTIONS (ELUR)
SYMBOLOGY
SUBJECT
ENVIRONMENTAL LAND USE RESTRICTION
AREA
— — —
A
Construction of Buildings within the Subject
Area shall not be permitted
Area: 129,610± Sq. Ft. (2.9 : Acres)
CM!
Building to be excluded from restriction
1,190 c S.F.
40
40
80 120
SCALE IN FEET
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\ N/F
\ 384 Old Turnpike, LLC
N/F
Wintee Realty, LLC
& DGS Holdings, LLC
N/F
TOWN OF SOUTHINGTON
TEMPORARY
OFFICE J
TRAILER I
BUILDING 2
(Building with Vapor
Barrier)
BUILDING 1
N/F
ancy Aust &
iia WTBrowninc
Marc R. Apfelbaum &
Lindsay Betzendaahl
.rcangelo
SYMBOLOGY
SUBJECT
AREA
ENVIRONMENTAL LAND USE RESTRICTION
Construction of Buildings within the Subject
Area shall not be permitted Area: 84G,250±
Sq. Ft. (19.3± Acres)
OOOO^
Building to be excluded from restriction
27,336± S.F.
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FIGURE 3
SCHEDULE OF
ENVIRONMENTAL LAND USE RESTRICTIONS (ELUR)
LEGEND
Fence Chain Link
Property Line
Road
Tree Line
Water Course
Scale: 1"=40'
VICINITY MAP
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Dirt Drive
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15
MAP REFERENCE:
15
SCALE IN FEET
30
45
1. "EASEMENT MAP, EXHIBIT C OF DECLARATION OF
ENVIRONMENTAL LAND USE RESTRICTION AND GRANT OF
EASEMENT, CHARLES V. ARCANGELO, 450 OLD TURNPIKE ROAD,
SOUTHINGTON, CONNECTICUT". DRAWING 1, SHEET 1 OF 1,
PROJECT NUMBER 61SL902.008, SCALE 1" = 50', DATE 2/20/2013.
LOUREIRO ENGINEERING ASSOCIATES, INC., 100 NORTHWEST
DRIVE, PLAINVILLE, CONNECTICUT. 860-747-6181.
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-------
ATTACHMENT 1
Photographic Documentation
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Photo 1: Inside Building 2 facing northwest. Note evidence of staining on ground
surface
Comm. No: 61SL902.001
Page 1 of 9
Loureiro
Lnjjmacrrp • Construcicn • • tnsry,-
V/a-jlw • Caciily • labuidkir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Photo 4: Alternate view of baseplate with intact caulking around the concrete floor
and the bolts.
Comm. No: 61SL902.001
Page 2 of 9
Loureiro
Lnjjmacrrp • Construcicn • tHAS • tnsr^v
Wash* • F#clily Serves* • labuiakir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Comm. No: 61SL902.001
Page 3 of 9
Loureiro
Lnjjmacrrp • Construcicn • tHAS • tnsr^v
Wash* • Fsciily S&'visias • labuiakir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Photo 7: Baseplate with intact caulking
Comm. No: 61SL902.001
Page 4 of 9
Loureiro
Lnjjmacrrp • Construcicn • tHAS • tnsr^v
Wash* • Fsciily S&'visias • labuiakir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Comm. No: 61SL902.001
Page 5 of 9
Loureiro
Lnjjmacrrp • Construcicn • tH-iS • tnsry,-
WnslH • Caciily Sa'vws; • labuidkir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Comm. No: 61SL902.001
Page 6 of 9
Loureiro
Lnjjmacrrp • Construcicn • tHAS • tnsr^v
Wash* • Fsciily S&'visias • labuiakir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Comm. No: 61SL902.001
Page 7 of 9
Loureiro
Lnjjmacrrp • Construcicn • tHAS • tnsr^v
Wash* • Fsciily S&'visias • labuiakir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Comm. No: 61SL902.001
Page 8 of 9
Loureiro
Lnjjmacrrp • Construcicn • tHAS • tnsr^v
Wash* • Fsciily S&'visias • labuiakir/
-------
Biennial Inspection of ELTJRs
Old South ington Landfill, Southington, Connecticut
September 13, 2019
Comm. No: 61SL902.001
Page 9 of 9
Loureiro
Lnjjmacrrp • Construcicn • tH-iS • tnsry,-
WnslH • Caciily Sa'vws; • labuidkir/
-------
ATTACHMENT 2
Inspection Forms
-------
Vapor Intrusion Inspection Form for Chuck Eddie's Property
Name of Inspector: ft. *
Weather: T o"\»
Signature of Inspector: ('*s*r .ILi - - t ——
Date & Time of Inspection:
i r 30
Are any new buildings/structures present on Site?
If YES, please explain:
YES
Is there evidence of Site construction activities in preparation of a new building/structure
if YES, please explain:
YES
LH2J
Are there any new additions to the current Site buildings?
If YES, please explain:
YES
^3^
Is there evidence of Site construction activities in preparation of a new addition to the current Site buildings
If YES, please explain:
YES I MO J
is the caulking/sealing applied to the bases and bolts of the vehicle lifts in Building 2 in place and in good condition
If NO, please explain:
NO
T»T
Are the seals c arid bolts of the vehicle lifts in Building 2 compromised or otherwise damaged
If YES, please explain:
YES
Was a Site Contact intervitw conducted ? "vTr" \
If NO, please explain:
tsf m
Town contacted to confirm no building permit applications have been submitted"'
If NO, please explain:
NO
Was photo-documentation performed as a part of this ELUR inspection!
If NO, please explain:
Provide observations of concrete slab integrity (i.e., cracks, chipping, corrosion/deterioration, staining, new penetrations, etc.l
a.4- ca v-c**' Cwe
L, r»tt \Vv
Comments/Notes:
-------
Vapor Intrusion Inspection Form for Radio Station Property
-------
ATTACHMENT 3
Town of Southington Building Department Documentation
-------
10/8/2019
Municity Connect
Municity Connect l/municipc"'ies)
Property Information for 450 Old Turnpike Rd
Apply for Permit
/municipalities/SouthingtonTownCT/application-types?
id=22718&recordType=Parcel)
Owner
Arcangelo Charles V
450 Old Turnpike Rd
Plantsville, CT 6479
Property Information
Parcel ID 064046
Property Class
Valuation
331 - Automotive Supplies Retail
Zone 1-1
Building/Construction
Acreage/Frontage/Depth
20.010000 acres/ feet/ feet
Square Feet ft2
Map
Permits (11)
Occupants (0)
Date
08/01/2013
Number
M-13-20215
Type
HVAC
Status
issued
Description
Direct replacement of existing gas/electric rooftop. CC #9319
03/07/2013
B-13-64547
Commercial - Fit-out
issued
Description
building fit up - NO HEAT C.O. #25145
01/04/2011
E-ll-32581
Electrical
issued
Description
electrical underground PVC- wiring for a fit-up CRS# 1592969
https://connect.municity5.com/municipalities/SouthingtonTownCT/parcel/22718/permit
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10/8/2019
Date
Number
Municity Connect
Type
Status
12/28/2010
B-10-61621
Commercial - Issue
Alteration/Renovation -
Interior
Contact Us
Town of Southington
196 North Main Street
Southington, CT 06489
(860) 276 6242
Need Help or Experiencing Issues?
griffinb@southington.org
(mailto:griffinb@southington.org)
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MUNICITY
(http://www.mu n ici ty sof twa re.com)
© 2019 Software Consulting Associates
View Privacy Policy
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10/8/2019
Municity Connect
Municity Connect l/municipc"'ies)
Property Information for 440 Old Iurnpike Rd
Apply for Permit
/municipalities/SouthingtonTownCT/application-types?
id = 31873&recordType= Parcel)
Property Information
Parcel ID 064047
Property Class
Valuation
433 - Radio, Television Trans
Zone 1-1
Building/Construction
Acreage/Frontage/Depth
3,100000 acres/ feet/ feet
Square Feet ft2
Map
Permits (11)
Occupants (0)
Date
03/14/2019
Number
E-19-39678
Type
Electrical
Status
issued
Description
Replace 3 antenna with 3 new, add 6 coax, reinforce tower with plates from 4' 6" - 84' 6"
03/14/2019
B-19-72655
Cell Tower/Sateilite
issued
Description
Remove and replace 3 existing antenna, add 6 new coax, reinforce tower 4' 6" - 84' 6" CA fee included
Use and Occupancy: U Type of Construction; 2B Total Sq Ft of Building: 400 sq ft Total Sq Ft of Permit
area: 400 sq ft Occupant load byd esign: 0 Is a sprinkler system required: No Is a sprinkler system
supplied: No
11/13/2014
B-14-66864
Commercial -
Alteration/Renovation -
Exterior
issued
https://connect.municity5.com/municipalities/SouthingtonTownCT/parcel/31873/permit
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10/8/2019
Date
Number
Municity Connect
Type
Status
Description
Modifications to an existing wireless telecommunications facility. C.C. #10594
07/21/2014 E-14-35336 Electrical Issued
Contact Us
Town of Southirtgton
196 North Main Street
Southington, CT 06489
(860) 276 6242
Need Help or Experiencing Issues?
griffinb@southington.org
(mailto:griffinb@southington.org)
POWERED BY
MUNICITY
(http://www.mu n ici ty sof twa re.com)
© 2019 Software Consulting Associates
View Privacy Policy
https://connect.municity5.com/municipalities/SouthingtonTownCT/parcel/31873/permit
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APPENDIX H
REFERENCE LIST
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APPENDIX H - REFERENCE LIST
Loureiro Engineering Associates, Inc. (Loureiro), 2012. Vapor Intrusion Groundwater Investigation
Report, Old Southington Landfill, Southington, Connecticut. July.
Loureiro, 2018. Remedial Action Completion Report, Old Southington Landfill, Southington,
Connecticut. June.
Loureiro, 2019. Re: Cap Effectiveness Monitoring Program Data Report - September 2019, Operations
& Maintenance Plan, Old Southington Landfill, Loureiro Comm. No. 61SL901.003. December 2.
Loureiro, 2020. Re: Biennial Inspection of Environmental Land Use Restrictions, Old Southington
Landfill Site, Southington, Connecticut, Commission Number: 61SL902.001. February 3.
Nobis Engineering, Inc., 2019. Trip Report, September 2019 Groundwater Sampling and Landfill
Inspection, Old Southington Landfill Superfund Site, Southington, Connecticut, Long-Term
Response Action Oversight, Task Order No. 0017-RX-ME-0158. December 30.
U.S. Environmental Protection Agency (EPA), 2002. OSWER Draft Guidance for Evaluating the Vapor
Intrusion to Indoor Air Pathway from Groundwater and Soils. U.S. Environmental Protection
Agency, Office of Solid Waste and Emergency Response, Washington, DC, EPA/530/D-02/004.
November 2002.
EPA, 2006. Record of Decision Summary. Old Southington Landfill Superfund Site, Southington,
Connecticut. September.
EPA, 2015. OSWER Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from
Subsurface Vapor Sources to Indoor Air. OSWER Publication 9200.2-154. June.
EPA, 2018. Final Close Out Report, Old Southington Landfill Superfund Site, Southington, Connecticut.
May.
EPA, 2014. Determining Groundwater Exposure Point Concentrations. OSWER Directive 9283.1-42.
February 2014.
EPA, 2014. Human Health Evaluation Manual, Supplemental Guidance: Update of Standard Default
Exposure Factors. OSWER Directive 9200.1- 120. February 6, 2014.
EPA, Office of Water, Drinking Water Health Advisory for Perfluorooctanoic Acid (PFOA), EPA 822-R-
16-005, May 2016.
Environmental Science & Engineering, INC. Remedial Investigation/Feasibility Study Volume 2B
Human Health/Ecological Risk Assessments Appendices A, B, C, D, E and F. December 3, 1993. Doc ID
280603.
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