SIXTH FIVE-YEAR REVIEW REPORT FOR
MOTTOLO PIG FARM SUPERFUND SITE
ROCKINGHAM COUNTY, NEW HAMPSHIRE
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Prepared by
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Digitally signed by
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Bryan Olson, Director Date
Superfund and Emergency Management Division
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Table of Contents
LIST 01 ABBREVIATIONS & ACRONYMS 2
I. INTRODUCTION 4
Site Background 4
FIVE-YEAR REVIEW SUMMARY FORM 5
II. RESPONSE ACTION SUMMARY 7
Basis for Taking Action 7
Response Actions 7
Status of Implementation 10
Institutional Controls 11
Systems Operations/Operation & Maintenance (O&M) 14
III. PROGRESS SINCE THE PREVIOUS REVIEW 15
IV. FIVE-YEAR REVIEW PROCESS 16
Community Notification, Community Involvement and Site Interviews 16
Data Review 16
Site Inspection 24
V. TECHNICAL ASSESSMENT 25
QUESTION A: Is the remedy functioning as intended by the decision documents? 25
QUESTION B: Are the exposure assumptions, toxicity data, cleanup levels and RAOs used at the time of the
remedy selection still valid? 26
QUESTION C: Has any other information come to light that could call into question the protectiveness of the
remedy? 35
VI. ISSUES/RECOMMENDATIONS 35
Other Findings 36
VII. PROTECTIVENESS STATEMENT 37
VIII. NEXT REVIEW 37
APPENDIX A - REFERENCE LIST
APPENDIX B - SITE CHRONOLOGY
APPENDIX C - SITE MAP
APPENDIX D - EPA NEWS RELEASE
APPENDIX E - INTERVIEW FORMS
APPENDIX F - DATA REVIEW FIGURES
APPENDIX G - TIME CONCENTRATION PLOTS
APPENDIX H - PFAS DATA REVIEW TABLES
APPENDIX I - SITE INSPECTION CHECKLIST
APPENDIX J - SITE PHOTOGRAPHS
APPENDIX K - REVIEW OF CLEANUP LEVELS
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LIST OF ABBREVIATIONS & ACRONYMS
1,1-DCA
1,1 -Dichloroethane
1,2-DCE
1,2-Dichloroethene
AGQS
Ambient Groundwater Quality Standard
ARAR
Applicable or Relevant and Appropriate Requirement
AROD
Amendment to the Record of Decision
ATSDR
Agency for Toxic Substances and Disease Registry
BLL
Blood Lead Level
CASRN
Chemical Abstracts Service Registry Number
CERCLA
Comprehensive Environmental Response, Compensation, and Liability Act
CFR
Code of Federal Regulations
COC
Contaminant of Concern
EPA
United States Environmental Protection Agency
ESV
Ecological Screening Value
ETBE
Ethyl Tertiary Butyl Ether
FDDA
Former Drum Disposal Area
FFS
Focused Feasibility Study
FYR
Five-Year Review
GMZ
Groundwater Management Zone
HFPO-DA
Hexafluoropropylene Oxide Dimer Acid (Gen-X)
HCL
Hydrochloric Acid
HQ
Hazard Quotient
ICs
Institutional Controls
IRIS
Integrated Risk Information System
MCL
Maximum Contaminant Level
MCLG
Maximum Contaminant Level Goal
mg/kg
Milligrams per Kilogram
mg/kg-day
Milligrams per Kilogram per Day
1-ig/dL
Micrograms per Deciliter
l-ig/L
Micrograms per Liter
MNA
Monitored Natural Attenuation
MRL
Minimal Risk Level
NA
Natural Attenuation
NCP
National Oil and Hazardous Substances Pollution Contingency Plan
ng/L
Nanograms per Liter
NHDES
New Hampshire Department of Environmental Services
NPL
National Priorities List
O&M
Operation and Maintenance
OHHRRAF
OLEM's Human Health Regional Risk Assessment Forum
OLEM
Office of Land and Emergency Management
OU
Operable Unit
PFAS
Per- and Polyfluoroalkyl Substances
PFBA
Perfluorobutanoic Acid
PFBS
Perfluorobutanesulfonic Acid
PFHpA
Perfluoroheptanoic Acid
PFHxA
Perfluorohexanoic Acid
PFHxS
Perfluorohexane Sulfonate
PFNA
Perfluorononanoic Acid
PFOA
Perfluorooctanoic Acid
PFOS
Perfluorooctane Sulfonate
PFPeA
Perfluoropentanoic Acid
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ppb
Parts per Billion
ppm
Parts per Million
PPRTV
Provisional Peer Reviewed Toxicity Value
ppt
Parts per Trillion
PRP
Potentially Responsible Party
RAO
Remedial Action Objective
RfC
Reference Concentration
RfD
Reference Dose
RI/FS
Remedial Investigation/Feasibility Study
ROD
Record of Decision
RPM
Remedial Project Manager
RSL
Regional Screening Level
SBA
Southern Boundary Area
SL
Screening Level
tBA
tert-Butyl Alcohol
TBC
To Be Considered
TCA
1,1,1 -Trichloroethane
TCE
Trichloroethene
THF
Tetrahydrofuran
UU/UE
Unlimited Use and Unrestricted Exposure
VES
Vacuum Extraction System
VI
Vapor Intrusion
VISL
Vapor Intrusion Screening Level
VOC
Volatile Organic Compound
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I. INTRODUCTION
The purpose of a five-year review (FYR) is to evaluate the implementation and performance of a remedy to
determine if the remedy is, and will continue to be, protective of human health and the environment. The
methods, findings and conclusions of reviews are documented in 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 (CERCLA) Section 121, consistent with the National
Oil and Hazardous Substances Pollution Contingency Plan (NCP) (40 Code of Federal Regulations (CFR) Section
300.430(f)(4)(ii)) and considering EPA policy.
This is the sixth FYR for the Mottolo Pig Farm Superfund site (Site). The triggering action for this statutory
review is the completion date of the previous FYR. The FYR has been prepared because 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 one operable unit (OU). This FYR addresses the sitewide OU.
EPA remedial project manager (RPM) Joe Cunningham led the FYR. Participants from EPA included former
RPM Richard Hull, attorney Susan Scott, human health risk assessor Ayana Cunningham, ecological risk
assessors Bart Hoskins and Valeria Paz, and community involvement coordinator Charlotte Gray. Other
participants included Brian Thornton and Michael Summerlin from the New Hampshire Department of
Environmental Services (NHDES) and Johnny Zimmerman-Ward and Ali Cattani from EPA support contractor
Skeo. The review began on 1/12/2023.
Appendix A includes a list of documents reviewed for this FYR. Appendix B provides a chronology of site
events.
Site Background
The 50-acre Site is located along Blueberry Hill Road in Raymond, New Hampshire. The Site, formerly used as a
pig farm, is about 3 miles south of the center of the town of Raymond and is surrounded by residential properties.
From 1975 through 1979, the property owner disposed of over 1,600 drums and pails of wastes into a quarter-acre
fill area (the Former Drum Disposal Area [FDDA]) on Site. In addition, at least one tanker of liquid waste was
emptied in the same area. These activities contaminated soil and groundwater at the Mottolo property primarily
with volatile organic compounds (VOCs) and aromatics. Arsenic was also found to be present in groundwater and
is the primary inorganic contaminant of concern (COC) at the Site.
The property is now mostly undeveloped wooded forest divided roughly in half by a brook (Brook A) (Figure 1).
About two acres in the southwest portion of the Mottolo property near the former piggery buildings, the FDDA
and the Southern Boundary Area (SBA) remain cleared. Site structures in and near the cleared area include two
concrete pads for the former piggery buildings and a former well house.
The Site is within the Exeter River drainage basin. The Exeter River is about 1,500 feet west of the property
boundary at its closest point. Brook A is a perennial stream that flows north across the Mottolo property, draining
about 285 acres at its confluence with the Exeter River. An ephemeral stream drains about 4 acres of the
undeveloped woodland between the cleared portion of the Site and Blueberry Hill Road. Runoff in the ephemeral
stream flows south to north into Brook A. A drainage swale crosses the Mottolo property from west to east, just
north of the FDDA, and discharges to Brook A.
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Three principal aquifer systems are located within the site area:
• Overburden groundwater flow with discharge ultimately to Brook A.
• The weathered and moderately fractured upper bedrock groundwater hydrogeologic flow system, in
which groundwater in joints and fractures flows toward and into the Brook A valley, and either discharges
to the overburden and Brook A or flows toward the Exeter River north of the Site.
• Groundwater migration in deeper bedrock, controlled by the secondary porosity of bedrock fractures and
joints. Based on previously performed geologic studies, the dominant trends of fractures and joints in the
study area include a primary northeast/southwest orientation and a secondary trend of
northwest/southeast. It is anticipated that most of the bulk groundwater flow in the deeper unit is
controlled by these two dominant orientations.
An overview of the conceptual site model is provided as Figure C-l in Appendix C. Groundwater contamination
is present in all aquifers.
The area near the Site is largely wooded, but single-family residences are present in all directions. Most
residences are served by private bedrock water supply wells of varying depths, however, 25 homes located to the
west and south of the Site were connected to a public water supply line in 2012 as required by the 2010
Amendment to the Record of Decision (AROD) due to discovery of site-related groundwater contamination. The
25 residential bedrock water supply wells were disconnected from service. Six active residential wells are
sampled annually and have consistently met drinking water quality standards for the duration of monitoring. The
residential wells are shown in Figure F-l in Appendix F.
FIVE-YEAR REVIEW SUMMARY FORM
SITE IDENTIFICATION
Site Name: Mottolo Pig Farm
EPA ID: NHD980503361
Region: 1
State: NH
City/County: Raymond/Rockingham County
SITE STATUS
NPL Status: Final
Multiple OUs?
No
Has the site achieved construction completion?
Yes
REVIEW STATUS
Lead agency: EPA
Author name: Joe Cunningham
Author affiliation: EPA
Review period: 1/23/2023 - 8/13/2023
Date of site inspection: 2/13/2023
Type of review: Statutory
Review number: 6
Triggering action date: 8/13/2018
Due date (fiveyears after triggering action date): 8/13/2023
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Last Modified: 4/4/2023
i i Property Boundary
Approximate Former
| Drum Disposal Area
(FDDA)
Approximate Southern
Boundary Area (SBA)
] Former Concrete Slab
Former Concrete Slab
(Piggery Building)
Wetland
Brook A
N Mottolo Pig Farm Superfund Site
A Town of Raymond, Rockingham County, New Hampshire
^ I Z
Disclaimer: This map and any boundary lines within the map are approximate and subject to change. The map is
not a survey. The map is for informational purposes only regarding EPA's response actions at the Site. Map image is
the intellectual property of Esri and is used herein under license. Copyright © 2020 Esri and its licensors. All rights
reserved. Sources: Esri, Maxar, Microsoft, Esri Community Maps Contributors, © OpenStreetMap, Microsoft, Esri,
HERE, Garmin, SafeGraph, GeoTechnologies, Inc, METI/NASA. USGS, EPA, NPS, US Census Bureau, USDA and
the 2021 Site Sampling Report.
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II. RESPONSE ACTION SUMMARY
Basis for Taking Action
From 1975 through 1979, the property owner disposed of approximately 1,600 55-gallon drums and 5-gallon pails
containing wastes into a depression adjacent to the main piggery building. In 1979 the site was reported to State
officials and preliminary investigations conducted by the New Hampshire Water Supply and Pollution Control
Commission (now the NHDES) indicated that the disposal area was contaminating soils, surface water and
groundwater with VOCs. EPA conducted a removal action between 1980 and 1982 (see Response Actions section
of this FYR Report). In 1991, a remedial investigation/feasibility study (RI/FS) was completed. The COCs
identified in the RI/FS are presented in Table 1.
Table 1: COCs, by Media
Media
COCs
Arsenic
1,1-Dichloroethane (1,1-DCA)
1,2-Dichloroethene (1,2-DCE [total])
Groundwater
Ethylbenzene
Tetrahydrofuran (THF)
1,1,1-Trichloroethane (TCA)
Toluene
Trichloroethene (TCE)
Vinyl chloride
Surface Water
1,1-DCA
1,2-DCE [total]
Sediment
1,1-DCA
1.1.1-TCA
Soil
Ethylbenzene
Toluene
Xylene
The RI/FS found that exposure to on-site soils, air, sediments, and surface waters did not pose an unacceptable
environmental or human health risk. However, a potential risk from drinking on-site groundwater was determined
to be above acceptable risk levels. Although soil did not present a direct risk to human health, contaminants in soil
did present a risk to groundwater via leachability based upon leaching analysis performed in the RI/FS.
Response Actions
Pre-Record of Decision (ROD) Actions
Between November 1980 and January 1982, EPA performed a removal action including excavation, staging,
testing, on-site storage, and off-site disposal of an estimated 160 tons of contaminated soil and 1,600 containers of
waste from the FDDA and SBA. EPA added the Site to the Superfund program's National Priorities List (NPL) in
July 1987.
Remedy Selection
EPA signed the Site's Record of Decision (ROD) in March 1991 and amended it in the 2010 AROD. The 1991
selected remedy included both source control and management of migration components. The 1991 ROD
specified the following remedial action objectives (RAOs) (also referred to as response objectives):
• To eliminate or minimize the threat posed to public health, welfare and environment by the current extent
of contamination of groundwater and soils.
• To eliminate or minimize the migration of contaminants from soils into the groundwater.
• To meet federal and state applicable or relevant and appropriate requirements (ARARs).
The 1991 remedy selected the following major remedy components:
• Implementation of institutional controls to ensure that no activities take place at the Site or in proximity to
the Site, which would either affect implementation of the selected remedy or cause exposures to
hazardous substances.
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• Installation of a groundwater interceptor trench to dewater the FDDA soils, temporary soil caps over the
SB A and FDDA, and installation of a soil vapor vacuum extraction system (VES) to remove VOC
contaminants from the soils.
• Natural attenuation of groundwater.
• Long-term sampling and evaluation of groundwater to assess compliance with cleanup levels through
natural attenuation.
Based on recommendations of the 2008 FYR Report, in 2009, NHDES implemented a sitewide groundwater,
surface water and sediment sampling event and expanded the residential sampling program to include additional
residences in the immediate vicinity of the Mottolo property. Sampling results revealed concentrations of arsenic
and trichloroethene (TCE) above the federal drinking water standard. NHDES immediately provided bottled water
(and in some cases point-of-entry treatment systems) to residences where exceedances were found, and to those
residences that were viewed as potentially having a hydraulic connection to the Site.
Subsequent actions were performed in fall and winter 2009/2010. The actions included a subsurface investigation
to identify residual sources of arsenic and VOCs on the Mottolo property, installation of three new deep bedrock
wells on the property, geophysical testing and water sampling, an aquifer pumping test and the additional
sampling of 65 nearby residential wells. The investigation also included sampling for 1,4-dioxane and
supplemental metal analyses, including manganese. 1,4 Dioxane was included due to its propensity to be co-
located with chlorinated solvents, as the former was commonly used as a stabilizer additive. EPA concluded that
changes to the groundwater chemistry due to the reductive dechlorination and resultant release of hydrochloric
acid (HCL) likely resulted in the mobilization of naturally occurring arsenic, resulting in concentrations above
background levels in the area adjacent to the western boundary of the Site. Homes located west and south of the
Mottolo property were identified for a focused feasibility study (FFS) where alternate water options would be
considered. 1,4-Dioxane was not detected above the laboratory reporting limit at the time (2 micrograms per liter
[Hg/L]).
The FFS was completed in July 2010. EPA issued the AROD in September 2010.
The 2010 AROD added the following RAOs:
• Prevent exposure to contaminants from residential wells used as drinking water wells where contaminants
exceed cleanup goals identified in the 1991 ROD/federal and state drinking water standards.
• Prevent the use of groundwater in the future where such use has the potential to hydraulically influence
the movement of groundwater contamination until cleanup goals established in the 1991 ROD and federal
and state drinking water standards are met.
The components of the final remedy include the following:
• Extension of the public water supply approximately 2 miles to provide drinking water to 25 residences
whose wells have been affected by contamination from the Site. These residences will be completely
disconnected from their existing private wells and the wells will be either converted to monitoring wells
or decommissioned following NHDES guidelines.
• A long-term groundwater monitoring program will be developed to monitor groundwater levels and
groundwater quality in residential areas to assess whether migration of the contaminated groundwater will
change once the homes are placed on the public water supply system and to confirm that other residential
wells are not at risk given the changes to groundwater hydrology.
• Institutional controls will be required in limited areas surrounding the Site to prevent the use of existing
wells and the installation of any new wells that may be pumped for any purpose in order to limit the risk
of exposure to subsurface contaminants in groundwater. These limited areas are where such groundwater
pumping has the potential to hydraulically influence the movement of groundwater contamination from
the Site, may alter the natural attenuation conditions on the Site and/or impact the remedy selected in the
1991 ROD.
• The amended remedy will use the FYR process to track the progress of meeting the RAOs and to
determine when remediation has been completed.
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Cleanup Levels
The 1991 ROD included interim groundwater cleanup levels (Table 2). The 2010 AROD updated the arsenic
cleanup level from 50 pg/L to 10 j^ig/L. The ROD estimated that after the source area soils were remediated by the
VES, the overburden groundwater would achieve cleanup levels within six years and the bedrock groundwater
would achieve cleanup levels within three years.
Table 2: Interim Groundwater Cleanup Levels
coc
Interim Cleanup Level
Qig/L)
Basis
Arsenic
10a
MCL/risk management
TCE
5
MCL
Vinyl chloride
2
MCL
1.1-DCA
81b
state health advisory/risk based
Toluene
1,000
MCLG
Ethylbenzene
700
MCLG
1.2-DCE (total)
<1
O
o
MCLG
THF
100
reference dose
1,1,1-TCA
200
MCLG
Notes:
MCLG = maximum contaminant level goal
MCL = maximum contaminant level
a. The 2010 AROD updated the interim cleanup level based on the updated
MCL for arsenic (effective February 22, 2002).
b. Based on state health advisory, risk-based as derived by the state
c. Based on more restrictive MCLG for cis-l,2-DCE
Source: Table 5, 1991 ROD and Table 1, 2010 AROD.
The 1991 ROD also included soil cleanup levels (Table 3). The soil cleanup levels were based on protection of
groundwater and separate levels were identified for the FDDA and the SBA (referred to as Area 1 and Area 2 in
the 1991 ROD).
Table 3: Soil Cleanup Levels
COC
Cleanup Level
(mg/kg)a
Area
TCE
0.07
Vinyl chloride
0.005
1.1-DCA
0.36
Toluene
14
FDDA (Area 1)
Ethylbenzene
17.4
1.2-DCE
0.46
1,1,1-TCA
2.1
TCE
0.004
SBA (Area 2)
1.2-DCE
0.020
Notes:
mg/kg = milligrams per kilogram
a. Soil cleanup levels were based on protection of groundwater
Source: Table 6A and 6B, 1991 ROD.
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Status of Implementation
In 1993, an in-situ VES was designed and constructed to treat VOC-contaminated soil within the FDDA. A
groundwater interceptor trench was also installed to dewater the soils as well as temporary soil caps. After three
years of operation, soil samples were taken in fall 1996 and analyzed for contaminants. No contamination was
found above soil cleanup levels in any of the samples. The VES system was shut down in fall 1996, and EPA
deemed the soil cleanup complete. During spring 1997, the VES cap was removed, and the area was graded and
seeded. The final VES closeout report was completed in 1997, and the source control portion of the remedial
action was considered complete by EPA on June 28, 1998.
During 2000, EPA decommissioned several wells, removed the chain link fence surrounding the Site, installed a
new entry gate, and modified the remaining wells. During fall 2001, the final components of the VES were
removed, including the groundwater interceptor trench.
Groundwater monitoring began in 1993. Between 1993 and 1998, monitoring varied from quarterly to three times
a year, and then changed to semiannual monitoring events. Annual water quality monitoring for site contaminants
began in 1999. Water quality monitoring included sampling groundwater from the network of on-site monitoring
wells (Figure 3) and surface water locations along Brook A. Routine surface water sampling was discontinued at
EPA's recommendation in June 2003 due to consistently low observed concentrations of contaminants; however,
surface water is still sampled periodically (see Data Review section of this FYR report).
During 2003, the responsibility for operating and maintaining the remedy was transferred officially from EPA to
NHDES. In addition, NHDES began sampling recently installed residential wells directly abutting the southern
border of the Site on Strawberry Lane. The residential well sampling program in this area has been ongoing since
2003. See the Data Review section of this FYR Report for more information on the status of residential well
sampling.
Consistent with the 2010 AROD, the approximately 2-mile water main extension was completed during summer
2012. Twenty-five residential bedrock water supply wells, located to the west and the south of the Mottolo
property, were disconnected from service. At nine of the 25 locations on Strawberry Lane, Blueberry Hill Road
and Windmere Drive, the submersible pumps and piping that connected the wells to the residences were removed,
a locking cap was fitted to the top of the well casing, and the wells were added to the network of site groundwater
monitoring wells. Within the vicinity of the Site, sampling of select residential bedrock water supply wells was
performed more frequently than site wells for the first year following construction of the water main extension
(2013), and annually with the site wells starting in 2014.
Based on recommendations of the 2013 FYR Report, in 2016, EPA conducted an evaluation of potential aquatic
risk in Brook A, which concluded that "contaminated groundwater at the Site does not have an adverse ecological
impact on the brook, even as a result of iron and manganese, which are not Site COCs."
Sampling for per- and polyfluoroalkyl substances (PFAS) in both groundwater and residential wells was
conducted for the first time in 2017. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were
detected at concentrations exceeding EPA's screening level and state AGQSs effective at that time in groundwater
collected from certain monitoring wells on the Site. PFOA and PFOS were detected at concentrations well below
the AGQS, or were not detected, in the deep bedrock wells and residential supply wells sampled. Based on the
results of the groundwater screening, NHDES has continued collection of groundwater samples for PFAS,
initiated a drinking water supply well screening program, and initiated a surface water screening program, to
assess the presence and extent of PFAS concentrations in each medium. See the Data Review section of this FYR
Report for more information on the ongoing PFAS monitoring.
NHDES is in the process of conducting an updated RI to determine the extent of PFAS in groundwater on the
northern end of the site to evaluate the potential for migration of site contaminants beyond the groundwater
management zone (GMZ) toward residential supply wells to the north (see Operations and Maintenance [O&M]
section of this FYR Report for additional information). Upon completion of the investigation and confirmation
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that observed contaminant concentrations do not suggest migration or unacceptable risk, these wells will be used
as sentry monitoring wells for long-term monitoring.
Institutional Controls
The 1991 ROD required institutional controls to ensure that no activities occurred at the Site or near the Site,
which would either affect implementation of the cleanup or cause exposures to contaminated groundwater until
groundwater cleanup levels were attained. The 2010 AROD expanded on the required institutional controls,
specifying that institutional controls will be required in limited areas surrounding the Site to prevent the
installation of any new wells that may be pumped for any purpose (e.g., drinking water) and could include local
ordinances, deed restrictions or GMZs.
Institutional controls have been implemented in the form of a town ordinance and restrictive covenants (Table 4,
Figure 2), as well as a GMZ. The Town of Raymond adopted an ordinance in April 2013, to prevent the
withdrawal of groundwater within the limits of the GMZ that includes both the Mottolo property and select
nearby properties to the northwest, west and southwest of the Site. On October 22, 2013, restrictive covenants
were recorded in the chain-of-title of the Site that further restricted specific activities and uses at the Site.
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Table 4: Summary of Planned and/or Implemented Institutional Controls (ICs)
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
Parcel(s)
IC
Objective
Title of IC Instrument
Implemented and Date (or
planned)
Groundwater
Yes
Yes
Mottolo Site
GMZ
(1) restricts installation of groundwater wells and
groundwater withdrawal; (2) restricts activities that
could disturb wetlands; (3) requires notice and
approval prior to undertaking aforementioned
activities.
Town of Raymond, NH; Town
Code Ordinance Section 292-3 (A),
adopted April 2013
Map 5, Lot 87
(1) restricts installation of groundwater wells and
groundwater withdrawal; (2) restricts activities that
could disturb soil; (3) restricts relocation of
contaminated soil; (4) restricts specific commercial
and industrial developments.
Notice of Restrictive Covenants,
October 2013
Soil
No
No
Map 5, Lot 87
Restricts activities that could disturb soil; restricts
relocation of contaminated soil; restricts specific
commercial and industrial developments.
Notice of Restrictive Covenants,
October 2013
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Disclaimer This map and any boundary lines within the map are approximate and subject to change. The map
is not a survey. The map is for informational purposes only regarding EPA's response actions at the Site. Map p I
image is the intellectual property of Esri and is used herein under license. Copyright © 2020 Esri and its
licensors. All rights reserved. Sources: Esri, Esri Community Maps Contributors, © OpenStreetMap, Microsoft,
Esri. HERE, Garmin, SafeGraph. GeoTechnologies, Inc, METI/NASA, USGS, EPA, NPS, US Census Bureau, Last Modified: 4/4/2023
US DA, Maxar, Town of Raymond, NH GIS and Town of Raymond Code Ordinance Section §292-3 (a).
Mottolo Pig Farm Superfund Site
Town of Raymond, Rockingham County, New Hampshire
0.5 Miles
Figure 2: Institutional Control Ma]
J Groundwater Management Zone
Parcel subject to 2013 Notice of Restrictive Covenants
Parcel
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Systems Operations/Operation & Maintenance (O&M)
The current remedy for the Site is natural attenuation; therefore, there were no active remediation or system
operations during this FYR period. O&M activities for the Site currently involve:
• Annual groundwater sampling of VOCs, arsenic, dissolved metals (iron and manganese), total organic
carbon and nitrate to support natural attenuation assessment and determination of long-term
protectiveness by NH DES and their contractor(s).
• Inspection and maintenance of the integrity of the groundwater monitoring network by NH DES and their
contractor(s).
NHDES updates the Sampling and Analysis Plan annually, the most recent version is dated September 2022.
The Town of Raymond is responsible for all O&M activities associated with the new waterline in the area of the
Site.
NHDES and their contractor conducted other activities at this Site as described below.
Well Abandonment
The landowner of 9 Strawberry Lane requested during fall 2020 to have the deep bedrock monitoring well on
their property (MW-S9) decommissioned. In response, NHDES and its consultant, GZA Geoenvironmental Inc.
(GZA), reviewed the locations and sampling history for deep bedrock monitoring wells both on and off the Site.
NHDES, in consultation with EPA, concurred with GZA's conclusion that the deep bedrock monitoring well
MW-S9 did not provide significant value to the ongoing monitoring program and could be decommissioned.
On June 1, 2021, NHDES and GZA decommissioned monitoring well MW-S9 in accordance with the
requirements of New Hampshire Code of Administrative Rules. Additional details about the well
decommissioning activities are provided in GZA's report Technical Memorandum - Well Decommissioning,
dated June 4, 2021, and is available viaNH DES's data and document management online portal OneStop.
Monitoring Well Installation
As part of the ongoing investigations to delineate the northern extent of PFAS in all groundwater zones, NHDES
installed several wells in that area of the Site. In September 2022, in accordance with the July 2022 Workplan,
NHDES's contractor attempted to install a monitoring well triplet consisting of one deep bedrock well, one
shallow bedrock well and one overburden well. During the drilling, bedrock was encountered at about 40 feet
below ground surface. At a depth of about 115 feet below ground surface a sand-filled fracture was encountered
that prevented the air hammer from drilling the borehole (MW-104D-1) deeper than 120 feet. Another borehole
(MW-104D-2) was drilled in a location approximately 5 feet from the first bedrock borehole and a sand-filled
fracture (anticipated to be the same sand-filled fracture encountered in the first bedrock borehole) was
encountered in bedrock at a depth of about 120 feet below ground surface and drilling was again discontinued so
that the target depth for the deep bedrock well was not reached. A third borehole was advanced into the
overburden, and overburden monitoring well MW-104S was installed at the proposed triplet location in
September 2022. In December 2022, NHDES installed a new bedrock borehole, MW-105D, which was drilled to
the target depth for the deep bedrock interval. Initial interval packer sampling of borehole MW-105D were non-
detect for all analyzed PFAS constituents. Boreholes MW-104D-1, MW-104D-2 and MW-105D will be
completed in the Summer of 2023 and additional sampling will be conducted in the Summer and Fall of 2023.
14
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III. PROGRESS SINCE THE PREVIOUS REVIEW
Table 5 includes the protectiveness determinations and statements from the 2018 FYR Report. Table 6 includes
the recommendations from the 2018 FYR Report and the status of those recommendations.
Table 5: Protectiveness Determinations/Statements from the 2018 FYR Report
ou#
Protectiveness
Determination
Protectiveness Statement
Sitewide
Short-term Protective
The remedy implemented at the Site is currently protective of human health and
the environment as envisioned by the 1991 ROD, as amended in 2010 in the short-
term, because the source control component of the remedy has been successfully
completed and ICs are in place and are currently effective in preventing exposure
to contaminated groundwater at the Site.
However, the remedy may not be protective in the long-term because the ROD
estimate for achieving groundwater cleanup standards was not achieved and there
currently is no accurate estimate for when or if NA [natural attenuation] can
achieve groundwater cleanup standards. The potential risks from the presence of
PFAS in Site groundwater also needs to be further assessed. In order for the
remedy to be protective in the long-tenn, the following actions need to be taken:
(1) Further data collection and analysis of the progress of NA is required to be
able to make a determination as to whether NA alone will be sufficient to achieve
groundwater cleanup standards within a reasonable time period, in conformance
with EPA Groundwater and MNA Guidance standards or if other remedial
measures may be required to restore the groundwater to beneficial reuse standards.
(2) Further evaluation of the presence (or nature and extent) of PFAS is needed to
determine if PFAS poses an unacceptable risk.
Table 6: Status of Recommendations from the 2018 FYR Report
OU#
Issue
Recommendation
Current
Status
Current Implementation
Status Description
Completion
Date (if
applicable)
Sitewide
Groundwater
cleanup levels for
COCs have not
been achieved
within the
timeframe
estimated in the
ROD.
Further assessment of
natural attenuation
processes is needed to
determine if
groundwater can
achieve cleanup
standards within a
reasonable period, in
conformance with
EPA Groundwater and
Monitored Natural
Attenuation Guidance
standards.
Completed
Initial assessment performed,
however additional data and
analysis is required.
3/9/2021
Sitewide
PFAS has been
detected in
groundwater.
Site-specific Screening
Levels indicates that
further evaluation is
needed to detennine
the extent of these
contaminants and the
risk associated with
contamination
identified.
Completed
Additional sampling for
PFAS in groundwater and
surface has been conducted
and potential for risk
identified.
11/26/2018
15
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IV. FIVE-YEAR REVIEW PROCESS
Community Notification, Community Involvement and Site Interviews
EPA issued an online news release in January 2023 to announce that the FYR was underway. A copy of the news
release is included in Appendix D. The results of the review and the completed FYR Report will be made
available at EPA's site profile page at www.epa.gov/superfund/mottolo.
During the FYR process, interviews were conducted to document any perceived problems or successes with the
remedy that has been implemented to date. The results of these interviews are summarized below.
INTERVIEW DOCUMENTATION FORM
Individuals interviewed for this FYR are listed below.
Brian Thornton
Project Manager
NHDES
4/10/2023
Ernest M. Cartier Creveling
Town manager
Raymond, NH
4/24/2023
Resident 1
Nearby property owner
Raymond, NH
4/10/2023
Resident 2
Nearby property owner
Raymond, NH
4/10/2023
In general, no specific complaints or concerns were noted with the Site remedy. Several individuals requested
additional information about the Site and indicated that information would be helpful through the Town's website.
Resident 2 expressed a general concern with development in the area and whether that would impact the
protectiveness of the Site. NHDES project manager, Brian Thornton, indicated that NHDES has updated the
AGQS for several contaminants that are monitored at the Site, including manganese, 1,4-dioxane, PFAS
compounds and arsenic. NHDES believes that EPA should consider adopting these updated AGQS" as interim
cleanup levels for the Site. NHDES also indicated that site monitoring has shown generally decreasing trends and
conditions continue to be favorable for natural attenuation of chlorinated ethenes, and that the combination of
extensive geophysical investigations, institutional controls and monitoring of both site groundwater and
residential supply wells continue to demonstrate protectiveness of the remedy.
NHDES also provided an update of applicable state ARARS including standards for site contaminants that may
have changed since the last five-year review.
Data Review
This FYR report reviewed data collected at the Site from 2019 through 2022 as summarized in the annual reports.
The residential well monitoring locations are shown in Figure F-l in Appendix F. The groundwater monitoring
well network and four surface water locations along Brook A are shown in Figure F-2 in Appendix F.
16
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The overall findings of this data review are as follows:
• All COCs are below cleanup levels except TCE, cis-l,2-DCE, vinyl chloride and arsenic.
• COCs TCE, cis-l,2-DCE, vinyl chloride and arsenic remain above cleanup levels in overburden and
shallow bedrock groundwater on Site.
• TCE and arsenic remain above cleanup levels in deep bedrock groundwater. All exceedances are
contained on Site except for arsenic in well MW-B31.
• COC concentrations are generally decreasing except for TCE, cis-l,2-DCE, vinyl chloride and arsenic in
overburden well MO-2S, cis-l,2-DCE in shallow bedrock wells MO-2DR and OW-2DR and TCE in
shallow bedrock well OW-2DR. NHDES believes these increases are likely due to a reduction in
groundwater withdrawal in the site vicinity, which has led to an increase in upward groundwater flow.
• Most of the remaining groundwater contamination is located downgradient of the FDDA in the
overburden and shallow bedrock.
• Natural attenuation parameters sulfate and total organic carbon as well as field parameters dissolved
oxygen, pH and oxidation/reduction potential are analyzed at select monitoring wells; however, the
annual reports do not include an interpretation of these data. Statistical evaluations are also not conducted.
Based on increasing concentration trends for TCE and arsenic, natural attenuation for overburden and
shallow bedrock does not appear effective in some areas.
• PFAS have been detected above state AGQSs and EPA RSLs in groundwater samples from overburden
and shallow bedrock generally associated with the VOC and arsenic plumes. PFAS have not been
detected at elevated concentrations in deep bedrock monitoring wells, residential wells or surface water
sample locations suggesting that PFAS contamination within the overburden and shallow bedrock
downgradient of source areas generally discharges to Brook A and is attenuated through dilution.
Water Level Monitoring
NHDES's contractor performs water level monitoring at overburden and bedrock monitoring wells to monitor
groundwater elevations and make comparisons with historical data pertaining to groundwater flow direction and
potential COC transport. In addition to looking at groundwater levels, NHDES's contractor measures the surface
water stage in Brook A. The most recent groundwater elevation contours maps for the overburden, shallow
bedrock and deep bedrock aquifer zones are provided as Figures F-3 through F-5 in Appendix F.
Vertical Gradients
As part of the water level monitoring, NHDES's contractor calculates the vertical gradient using the multilevel
well clusters. Water level measurements indicate a range of upward and downward vertical components of the
hydraulic head gradient. In 2022, an upward gradient was observed at six locations and a downward gradient was
calculated at three locations (MW-20, MW-23 and OW-4). Well clusters with calculated upward gradients are
generally located within the lower elevation areas of the site proximate to Brook A, and well clusters with
calculated downward gradients are located within the higher elevation areas near the southern Site boundary. One
exception relative to the location of clusters with calculated upward vertical gradients is MW-8, which is located
south of the SBA. The well clusters with downward vertical gradients include OW-4, located immediately
east/northeast of the FDDA, MW-20, located southwest of the SBA, and MW-23, located south-southeast of the
SBA. The calculated hydraulic head in the multi-zone well MW-103D fluctuate slightly and both upward and
downward gradients have been observed between Zone 2 to 3 and Zone 3 to 4.
Overburden and Shallow Bedrock Groundwater Flow
Groundwater flow in the overburden and shallow bedrock on the west side of Brook A and downgradient of the
FDDA is east-northeast toward Brook A. Groundwater flow to the southwest of the SBA is to the south/southwest
between wells MW-20S and MW-23S. Consistent with historical results, the groundwater flow direction in the
overburden and shallow bedrock suggests a groundwater divide is present in the vicinity of monitoring wells
MW-7, MW-8, MW-20 and MW-21. NHDES's contractor attributes this divide to the downward vertical gradient
observed at well cluster MW-20. Figures F-3 and F-4 in Appendix F show the groundwater elevation contours
and inferred groundwater flow direction for overburden and shallow bedrock, respectively, from October 2022.
17
-------
Deep Bedrock Fracture Flow
The deep bedrock wells on site are mostly open boreholes without specific vertically-screened intervals.
Therefore, groundwater elevation measurements in the deep bedrock wells represent combined conditions across
multiple hydraulically active fractures. Groundwater flow through fractured bedrock systems is complex and the
elevation contours are considered approximate. Figure F-5 in Appendix F includes both hydraulic head elevations
and estimated elevation contours. Based on the 2022 hydraulic head data, deep bedrock groundwater west of
Blueberry Hill Road flows primarily to the west/northwest. Deep bedrock groundwater flow on the Mottolo
property within the vicinity of the FDDA is dominated by an east/northeastward flow toward Brook A. Deep
bedrock groundwater flow south of the Mottolo property (between the property and Strawberry Lane) is primarily
to the east. The conceptual site model for the deep bedrock fracture system indicates that flow to the east and west
at the Site may be dominated by different fracture systems. Flow to the west is likely dominated by the shallow-
dipping "green plane" fracture (as referred to in the 2009 Supplemental Investigation). The dominant features
controlling eastward flow are currently uncertain.
Groundwater Quality Monitoring
Annual groundwater monitoring is conducted in October. During the monitoring events, NHDES's contractor
samples bedrock and overburden wells to evaluate contaminant concentrations and trends. During the October
2022 sampling event, groundwater sampling was performed at 14 bedrock locations (including the four discrete
zones within deep bedrock well MW-103D) and five overburden monitoring locations. Please note that the
naming convention for monitoring wells includes the prefix "MOT_" (e.g., MOT_MW-3D), however, this prefix
is dropped for simplicity.
Overburden and Shallow Bedrock Groundwater Quality
During this FYR period, TCE, vinyl chloride and arsenic consistently exceed their cleanup levels at on-site
overburden wells MO-2S and MO-3SR. TCE, cis-l,2-DCE, vinyl chloride and arsenic consistently exceed their
cleanup levels at on-site shallow bedrock wells OW-2DR, MO-2DR and MO-3DR (Table 7). The most recent
results for the overburden wells and shallow bedrock wells are shown in Figures F-6 and F-7 in Appendix F,
respectively. A maximum TCE concentration of 480 (ig/L was detected in shallow bedrock well OW-2DR during
2021, which is over two times the highest detected concentration in the previous five years. In 2022, TCE was
detected at 380 (ig/L at OW-2DR. OW-2DR is downgradient of the FDDA. TCE concentration data in well OW-
2DRhas indicated an increasing trend since September 2014 (Figure G-l in Appendix G). The dissolved phase
plume in the overburden shallow bedrock groundwater is generally consistent with contaminant transport to the
east/northeast toward Brook A.
NHDES's contractor presents concentration trends overtime in each annual report. These are included in
Appendix G. The 2022 concentrations trends for TCE, cis-l,2-DCE, vinyl chloride and arsenic at overburden and
shallow bedrock wells are presented in Figures G-l through G-4. In overburden well MO-2S, VOCs have been
slightly increasing since 2012. Arsenic concentrations, initially increasing from 2006 to 2017, are now generally
decreasing. TCE and cis-l,2-DCE in overburden well MO-3SR indicate a decreasing trend since 2016 and arsenic
and vinyl chloride have been decreasing since 2007 and 2010, respectively.
In shallow bedrock, TCE concentrations indicate a decreasing trend in well MO-3DR and MW-22D since 2011
(Figure G-l in Appendix G). NHDES's contractor indicates this decrease in conjunction with the increase
observed in MO-2S may be the result of the change in groundwater flow associated with the reduced use of local
groundwater pumping since the installation of the water line. Cis-1,2-DCE is generally increasing in MO-2DR
since 2007 (Figure G-2 in Appendix G). Concentrations in other wells are generally stable. Vinyl chloride shows
a decreasing trend for MO-3DR and OW-2DR and stable conditions at other wells (Figure G-3 in Appendix G).
Arsenic concentrations in shallow bedrock are generally stable with OW-2DR showing an overall decreasing
trend (Figure G-4 in Appendix G).
Bedrock Groundwater Quality
TCE and arsenic were above groundwater cleanup levels in deep bedrock wells. In 2022, TCE was detected above
the cleanup level from on-site wells MW-102D and MW-103D Zones 1 through 3 (Figure F-8 in Appendix F,
18
-------
Table 7). The maximum concentration of TCE was detected in MW-103D Zone 2 at 13 (ig/L. TCE concentrations
indicate an overall decreasing trend since 2012 with some fluctuations (Figure G-5 in Appendix G). Cis-1,2-DCE
remains below the cleanup level (Figure G-6 in Appendix G).
In 2022, arsenic was detected above both the cleanup level (10 j^ig/L) and the AGQS (5 j^ig/L) in deep bedrock
borehole wells MW-B31 (offsite) and on-site wells MW-102D and bedrock sampling zones MW-103D Zone 3
and Zone 4 (Figure F-9 in Appendix F). The maximum concentration was observed at MW-103D Zone 4
(0.02692 mg/L). Arsenic concentration trends (Figure G-7 in Appendix G) initially decreased from 2010 to 2012
and have since generally stabilized.
During this FYR period, there were exceedances of the arsenic interim groundwater cleanup level in MW-
B31,which is just outside the western site boundary and well within the GMZ.
19
-------
Monitoring
MO-
2S
MO-
2DR
MO-
3SR
MO-
3DR
ow-
2DR
ow-
4SR
MW-
12D
MW-
22D
MW-
102D
MW-
103D
-1
MW-
103D-
2
MW-
103D-
3
MW-
103D-
4
MW-
B31
COC
W J
U on
H 3.
2019
55
7
30
46
130
--
5.6
8.4
12
5.2
19
14
6.8
--
2020
--
15
32
42
180
--
--
~
11
6.8
28
18
6.9
~
2021
7.5
16
35
49
480
~
--
10
8.6
17
10
6.7
~
2022
36
13
15
45
380
--
~
5.5
10
13
13
9.5
~
~
W
U
® 5
th i
VI
u
2019
--
120
--
160
73
--
~
~
--
--
--
--
~
~
2020
--
85
--
140
97
--
--
~
--
--
~
~
~
--
2021
--
98
--
160
170
--
~
~
~
~
--
~
~
~
2022
--
98
--
160
130
~
~
--
~
~
~
--
~
~
2 3
u
2021
3.9
5.2
5.1
9.7
--
~
--
~
~
--
~
~
~
--
2022
5.5
3.8
--
11
--
~
~
~
~
~
--
~
~
~
Arsenic
(mg/L)
2019
0.4286
0.01113
T
0.5676
0.07354
T
0.0986
0.0378
~
--
0.01684
~
0.0116
0.0155
0.0275
0.0151
2020
0.1640
0.0179
0.4786
0.0896
0.0459
--
~
~
0.01696
~
0.0114
0.0109
0.0256
0.0139
2021
0.2000
--
0.4902
0.0783
0.0359
~
~
~
0.01657
~
~
0.0196
0.0237
0.0135
2022
0.2039
--
0.4367
0.0934
0.0244
0.0121
--
~
0.01424
--
~
0.0182
0.0269
0.0134
Notes:
Source: Table 5A, 2022 Site Sampling Data Report
For samples where a duplicate sample was collected, the higher result of the duplicate and parent sample is shown.
T = metal analytical result qualified because the turbidity was greater than 25 NTUs at the time of sampling
G = estimated concentration qualified by the laboratory due to co-elution with a non-target compound
-- = Result did not exceed ROD Cleanup Level
ROD Cleanup Levels:
TCE = 5 jig/L
Cis-1,2-DCE = 70 jig/L
Vinyl Chloride = 2 (.ig/L
Arsenic = 0.01 mg/L
20
-------
Residential Well Sampling Results
NHDES's contractor sampled six residential wells annually during this FYR period (Figure F-l in Appendix F
shows the residential well locations). Each well serves as a primary water supply for the residence. Samples were
analyzed for VOCs, total arsenic and PFAS. VOCs were not detected in excess of state AGQSs during this FYR
period. In 2019, 2021 and 2022, methyl tert-butyl ether (MtBE) was detected in a single residential well, however,
concentrations were two orders of magnitude below the AGQS and consistent with historical results. The source
of the MtBE contamination is not known, however is not believed to be related to the Mottolo Site and is not
currently a COC.
Total arsenic was detected at concentrations below the cleanup level (10 j^ig/L) in drinking water samples through
2022. In 2021 the state AGQS was updated from 10 (ig/L to 5 (ig/L. In 2018 - 2020, concentrations of Arsenic
were equal to, or exceeded, the AGQS (although were less than the ROD cleanup level). However, concentrations
appeared to decrease and were below the AGQS in 2021 and 2022 samples in all wells (Figure G-8 in Appendix
G). The PFAS results are provided below under PFAS Screening Results sub header.
Surface Water Screening Results
In 2021, NHDES's contractor sampled four surface water locations. Sampling was planned for 2020; however,
drought conditions prevented sample collection. The 2021 samples were analyzed for VOCs to assess whether the
increasing TCE concentration trend observed in overburden wells near Brook A had impacted the brook. Samples
were also analyzed for PFAS (see PFAS section below).
Figure F-2 in Appendix F shows the surface water sampling locations. Consistent with historical results, VOC
concentrations were not detected in surface water above reporting limits. Surface water samples were not
collected in 2022.
PFAS Screening Results
Groundwater Wells
In 2021, seven monitoring wells (overburden and shallow bedrock) were sampled for PFAS. In 2022, eight
monitoring wells (overburden and shallow bedrock) were sampled for PFAS. Because PFAS concentrations
detected in groundwater samples collected from deep bedrock wells in 2017 and 2018 did not exceed state
AGQSs or EPA RSLs collection of deep bedrock groundwater samples for PFAS was discontinued.
The 2022 PFAS results are generally consistent with historical results (see Table H-l in Appendix H). Monitoring
well MW- 12S was sampled for PFAS in 2021 for the first time to confirm that PFAS was not migrating under
Brook A. No PFAS was detected above the reporting limits confirming that PFAS is not migrating under Brook
A. The 2022 results indicated the following:
• Concentrations of PFOA in groundwater samples collected from shallow bedrock wells MW-12D, MW-
22D, and OW-2DR, and overburden wells MO-2S, MO-3SR, and MW-22S, exceeded the EPA RSL of 6
ng/L and AGQS of 12 ng/L for PFOA. Detected PFOA concentrations in excess of the EPA RSL ranged
from 13 ng/L in the groundwater sample collected from MW-12D to 445 ng/L in the groundwater sample
collected from MO-3SR. These data are consistent with transport of PFAS from the FDDA and SB A to
the east-northeast.
• Consistent with prior years, concentrations of PFOS detected within groundwater samples collected from
overburden wells MO-2S, MO-3SR, and MW-22S and shallow bedrock wells MW-22D and OW-2DR
exceeded the EPA RSL of 4 ng/L and AGQS of 15 ng/L. Detected PFOS concentrations in excess of the
EPA RSL ranged from 27.3 ng/L in the groundwater sample collected from MW-22S to 203 ng/L in the
sample collected from MO-3SR.
• Detected concentrations of PFNA did not exceed the AGQS of 11 ng/L or the EPA RSL of 5.9 ng/L in the
groundwater samples collected during 2022. Detected concentrations of PFHxS exceeded the AGQS of
18 ng/L in the groundwater sample collected from MO-2S (28.5 ng/L) and exceeded both the AGQS and
21
-------
EPA RSL of 39 ng/L in the groundwater samples collected from MO-3SR (137 ng/L) and OW-2DR (66.9
ng/L).
• Overburden monitoring well MW-104S was sampled for PFAS in groundwater for the first time in 2022
to assess whether PFAS in overburden groundwater migrates further downgradient beyond well couplet
MW-22. PFOA was detected in the groundwater sample collected from MW-104S at a concentration
below the AGQS (12 ng/L) and 2022 EPA RSL (6 ng/L) at 2.60 ng/L.
The PFAS results are shown in Figure F-10 in Appendix F. Overall the exceedances observed in the overburden
and shallow bedrock monitoring wells were generally consistent with the distribution of the TCE plume
(downgradient of the FDDA and SB A). The presence and location of the PFAS exceedances are likely related to
the industrial chemicals disposed within the FDDA. Due to the PFOA and PFOS detections in downgradient well
MW-22, NHDES installed monitoring well clusters MW-104 and MW-105 downgradient of MW-22 in late 2022
to assess the attenuation of PFAS prior to the northern boundary of the property. Sampling results from these
wells are pending.
Starting in the 2022 Annual Report, NHDES's contractor created concentration trends over time for PFOA,
PFOS, PFNA and PFHxS in overburden and shallow bedrock groundwater (Figures G-9 through G-12 in
Appendix G). PFOA, PFOS and PFHxS concentrations in OW-2DR and MO-3SR indicate overall increasing
trends since November 2018. PFOS concentrations at MO-2S also indicate an increasing trend. PFNA
concentrations show an overall decreasing trend. NHDES will continue to monitor PFAS trends overtime.
Residential Wells
PFOA was the only PFAS compound detected above laboratory reporting limits (maximum limit of 2.0 ng/L) in
residential well samples in 2021 and 2022. Prior to 2021, other PFAS compounds were also detected in addition
to PFOA; however, these compounds do not have any screening criteria. The PFOA detections from 2017 through
2022 did not exceed applicable AGQSs or EPA RSLs. The highest detected PFOA concentration was 3.8 ng/L
(2018). In 2022, the highest PFOA concentrations was 2.90 ng/L. See Figure F-l 1 in Appendix F.
Surface Water
During 2019, NHDES initiated a surface water screening program to assess the presence and extent of PFAS
concentrations in surface water. Of the 36 PFAS compounds analyzed for, four compounds were detected
in the surface water samples collected, including PFOA, PFOS, perfluorobutanesulfonic acid (PFBA) and
perfluorobutane sulfonic acid (PFBS) (Table H-2 in Appendix H). In 2019, PFOA was detected in each of the four
surface water locations ranging from 2.51 ng/L in the sample collected from upgradient surface water location
SW-1 to 6.53 ng/L in the sample collected from SW-3. PFOS was detected in surface water locations SW-3 (4.25
ng/L) and downgradient surface water location SW-100 (2.12 ng/L). Variations in detections of PFAS analytes
and concentrations was not observed between the upgradient and downgradient surface water sampling locations.
NHDES requested confirmatory sampling of surface water for PFAS during the fall 2020 sampling event. Due to
low-water drought conditions, Brook A was dry in October 2020 and confirmatory sampling was postponed
until the fall 2021 monitoring event. During the 2021 event, seven PFAS compounds were detected above the
laboratory reporting limit (maximum limit of 2 ng/L). Detected PFAS values ranged from 1.92 ng/L for
perfluoroheptanoic acid (PFHpA) at SW-1 to 8.23 ng/L for PFOA collected at SW-100. The 2021 surface water
results are shown in Figure F-12 in Appendix F. Surface water sampling was not conducted in 2022.
Currently, no NHDES standards or site-specific screening levels have been developed for PFAS in surface water.
EPA Region 1 established ecological screening values (ESVs) to support screening-level ecological risk
assessments at sites where PFAS have been detected in soils and surface waters. This FYR Report compared the
surface water sampling results to the Region 1 ESVs (Table 8). There were no exceedances of the Region 1
ESVs.
22
-------
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Mottolo Pig Farm Superfund Site
Town of Raymond, Rockingham County, New Hampshire
Disclaimer: This map and any boundary lines within the map are approximate and subject to change. The map is
not a survey. The map is for informational purposes only regarding EPA's response actions at the Site. Map image is
the intellectual property of Esri and is used herein under license. Copyright © 2020 Esri and its licensors. All rights
reserved. Sources: Esri. Maxar. Microsoft, Esri Community Maps Contributors, © OpenStreetMap, Microsoft, Esri,
HERE, Garmin, SafeGraph, GeoTechnologies, Inc, METI/NASA, USGS, EPA, NPS, US Census Bureau, USDA, the
2021 Site Sampling Report and the 2022 Site Sampling Report
Last Modified: 6/29/2023
Figure 3: Monitoring Well Locations
MWj8Dl
Imw5s]
Overburden
Monitoring Well
Shallow Bedrock
Monitoring Well
Deep Bedrock
Monitoring Well
Surface Sampling
Location
Property Boundary
Approximate Former
Drum Disposal Area
(FDDA)
Approximate Southern
Boundary Area (SBA)
Brook A
[Mw=s:ioj
[MW;S8j
23
-------
Table 8: 2021 Surface Water PFAS Detections
Sampling Location
PFBA
PFPeA
PFHxA
PFHpA
PFOA
PFBS
PFOS
AGQS*
NA
NA
NA
NA
12
NA
15
EPA RSL
NA
NA
NA
NA
6
NA
4
EPA Region 1 ESVb
64,000
NA
28,800
NA
307,000
400,000
22,600
SW-1
3.12
2.58
2.85
1.92
4.57
3.92
<1.88
SW-2a
3.22
2.58
3.02
2.10
7.32
4.06
2.54
SW-3
3.18
2.45
3.05
2.24
8.05
3.94
2.99
SW-100
2.59
2.25
2.75
1.99
8.23
3.28
2.99
Notes:
All units in ng/L
NA = not applicable, no screening level exists for this PFAS compound
Bold = exceeds EPA RSL
PFPeA = perfluoropentanoic acid
PFHxA = perfluorohexanoic acid
a. Duplicate sample was collected at this location; the higher result from the parent and the duplicate is shown.
b. Table 3-3 Freshwater Chronic Exposure ESVs for Aquatic Life, 2021 Derivation of PFAS Ecological Screening
Values
Source: Table 6B, 2021 Site Summary Report.
Site Inspection
The site inspection was conducted on 2/13/2023. In attendance were Joe Cunningham, Richard Hull, Bart
Hoskins, Charlotte Gray and Joanne Kitchell from EPA, Brian Thornton and Michael Summerlin from NHDES,
Megan Murphy from NHDES contractor GZA, and Johnny Zimmerman-Ward and Ali Cattani from EPA support
contractor Skeo. The purpose of the inspection was to assess the protectiveness of the remedy. Appendix I
includes the completed site inspection checklist. Appendix J includes photographs from the site inspection. Site
inspection participants met inside the gated access to the Site off Blueberry Hill Road. NHDES had unlocked the
gate prior to the inspection. Participants walked the Site and observed the former well house building, which
showed some signs of recent graffiti. The FDDA and SBA areas were well vegetated. These areas are mowed and
maintained to allow access to the monitoring wells during sampling events.
Participants observed several wells, which were labeled and secure, as well as Brook A, which was flowing.
Participants then headed to the northern property boundary to observe the newly installed MW-104 well cluster
and MW-105. All wells except MW-104S had been recently vandalized and the caps were damaged and/or
missing. The casing for MW-104S was able to be moved horizontally and vertically by hand up to 1" in all
directions. Both MW-104 and MW-105 were observed to be under artesian conditions and were actively releasing
water to the surface, although MW-105 had a noticeably higher flow rate visually estimated at < 1 L/min. GZA
returned to the Site later that day and replaced the well caps and secured the wells. In this same area of the Site,
participants observed a sugaring (maple syrup making) operation located adjacent to the Site that had expanded its
operation to the sugarbush on the Site property and was actively extracting sap. In addition, there was evidence
that the property is frequently used for recreation and hunting, as multiple footprints were observed in the
snowpack as well as multiple "trail cams" throughout the property. No new land development or drinking water
well installation was observed along the perimeter of the property, and the institutional controls appear to be
effective.
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V. TECHNICAL ASSESSMENT
QUESTION A: Is the remedy functioning as intended by the decision documents?
Question A Summary:
Overall, the remedy is functioning as intended by the 1991 ROD and 2010 AROD. Exceptions are noted below.
Remedial Action Performance
The source control components of the selected remedy included excavation and off-site disposal of 1,600
containers of waste and an estimated 160 tons of contaminated soil from the FDDA and SB A and installation of a
groundwater interceptor trench and the VES. After three years, soil results met the soil cleanup levels based on
protection of groundwater and the system was turned off in late 1996. All aboveground components of the VES
were removed from the treated area in December 1996, the interceptor trench and liner were removed from the
FDDA in December 2001, and the final VES closeout report was completed in 1997. The source control remedial
action was considered complete by EPA on June 28, 1998.
The remaining remedy components include natural attenuation for groundwater and institutional controls to
prevent consumption of contaminated groundwater until groundwater cleanup levels are attained. After TCE and
arsenic were discovered above drinking water standards in 2009/2010, EPA amended the 1991 ROD. The 2010
AROD added extension of a public water supply, expanded groundwater institutional controls, and expanded off-
site groundwater monitoring requirements. The extension of the public water supply provides safe drinking water
to the 25 affected residences near the Site. Institutional controls in the form of an ordinance creating a
Groundwater Management Zone and restrictive covenants on the Site have been implemented to prevent
consumption of contaminated groundwater. The restrictive covenants are working as intended to protect from
groundwater exposure. However, as noted below, the property is State-owned, unfenced, and unposted land which
is therefore is available to the public by Common law. Hence, use of the property for recreational (hiking,
hunting) and illicit (vandalism and damage to monitoring wells) purposes continue to occur.
The 1991 ROD indicated that natural attenuation would achieve cleanup levels six years after soil cleanup, which
would equate to achieving cleanup levels in 2004. In response to an issue in the 2013 FYR Report, GZA
conducted an initial assessment of natural attenuation processes and estimated cleanup time. The results of the
assessment of MNA and cleanup times were detailed in Appendix F of the Fall 2017 Site Sampling Data Report
(July 27, 2018) and included time to closure estimates. The results demonstrated that natural attenuation processes
are occurring and effective at reducing the concentration of site contaminants in groundwater, but that regression
calculations based on Site concentration trends should be reevaluated at regular intervals during the
Site Five Year Reviews to refine the time to closure estimates. Based on increasing concentration trends for TCE
and arsenic in some overburden and shallow bedrock wells, and the recommendations from the 2018 assessment
of MNA and cleanup times, continued assessment of natural attenuation processes and evaluation of regression
calculations based on concentration trends is needed.
NHDES conducts long-term groundwater monitoring. The results of the long-term monitoring indicate that COC
concentrations in some overburden and shallow bedrock wells continue to increase, possibly due to the change in
groundwater flow conditions. Residential wells are sampled annually, and results do not exceed groundwater
cleanup levels. Arsenic concentrations detected in residential wells have been stable since 2009. In the period
examined for this FYR (2018 - 2022), three residential wells were equal to, or exceeded, the state AGQS for
arsenic (5 (ig/L) in 2018, 2019, and 2020. However, the concentrations appeared to decrease and there were no
exceedances of the State AGQS or cleanup level in 2021 or 2022. NHDES will continue monitoring residential
wells.
PFAS compounds have also been detected above the AGQSs and EPA RSLs generally co-located with the VOC
and arsenic plumes. NHDES installed new wells in the northern portion of the Site to further delineate PFAS in
groundwater. Results were not available for this FYR. NHDES is conducting an updated RI to determine the
extent of PFAS in groundwater and establish bedrock sentry monitoring wells.
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PFOA was the only PFAS compound detected above laboratory reporting limits (maximum limit of 2.0 ng/L) in
residential well samples in 2021 and did not exceed AGQSs, EPA health advisory levels or EPA RSLs that were
applicable at the time. In 2022 EPA revised the toxicity values for several PFAS compounds which resulted in
changes to the RSL. Future residential well values will be compared to the RSL or, if available and promulgated,
a MCL. VOCs in surface water results continue to be less than laboratory detection limits. During the 2021 event,
seven PFAS compounds were detected above the laboratory reporting limit (maximum limit of 2 ng/L) in surface
water. Detected PFAS values ranged from 1.92 ng/L PFHpA at SW-1 to 8.23 ng/L PFOA collected at SW-100.
NHDES will continue monitoring.
Implementation of Institutional Controls and Other Measures
In 2013, the Town of Raymond adopted an ordinance to restrict the withdrawal of groundwater within the limits
of a GMZ that includes both the Site and select properties to the south (Strawberry Lane), west (Blueberry Hill
Road and Windmere Drive) and north-northwest (Perimeter Road subdivision), as well as an undeveloped lot to
the west-southwest and conservation land between the Site and the Exeter River. The ordinance restricts the use
of groundwater by prohibiting installation or reactivation of any wells for any purpose excepting closed-loop
geothermal use, and prohibits disturbance to wetlands within the GMZ, unless approved in advance by EPA,
NHDES and the Town of Raymond Board of Selectmen. Groundwater contamination remains within the GMZ
which is monitored annually by NHDES. In addition to the GMZ, there is a notice of restrictive covenants on the
former Mottolo property, which restricts soil disturbance and relocation and specific development.
QUESTION B: Are the exposure assumptions, toxicity data, cleanup levels and RAOs used at the time of
the remedy selection still valid?
Question B Summary:
No. There have been changes in exposure assumptions, standards, and toxicity data since the 1991 ROD and the
2010 AROD were issued as discussed below.
The changes as described below are not expected to alter the protectiveness of the remedy because affected
residences are now serviced by a public water supply. In addition, institutional controls are in place that prohibit
use of groundwater, installation, or reactivation of any wells for any purpose except closed-loop geothermal, and
disturbance to wetlands, unless approved in advance by EPA, NHDES and the Town of Raymond.
During the FYR inspection, EPA and NHDES observed tree sap being extracted and collected from trees located
on the Site. The neighboring sugarbush operator to the west had expanded their sugarbush operation onto the Site.
The newly installed well cluster is very close to these trees. Depending on the results of the ongoing PFAS
investigation, additional research may be needed to determine if groundwater beneath trees where sap is collected
is impacted by site contaminants.
Changes in Standards and To Be Considered Criteria (TBCs)
New standards (federal or state statutes and/or regulations), as well as new TBC guidance, should be considered
during the FYR process as part of the protectiveness determination. Under the NCP, if a new federal or state
statute and/or regulation is promulgated or a new TBC guidance is issued after the ROD is signed, and, as part of
the FYR process it is determined that the standard needs to be attained or new guidance procedures followed to
ensure that the remedy is protective of human health and the environment, then the FYR should recommend that a
future decision document be issued that adds the new standard as an ARAR or guidance as a TBC to the remedy.
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
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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, pp. 1-56.)
Interim groundwater cleanup levels selected in the 1991 ROD and amended in the 2010 AROD were based on 1)
EPA MCLs and non-zero maximum contaminant level goals (MCLGs), which were established as ARARs in the
1991 ROD. The 1991 ROD indicated that the groundwater cleanup levels would be interim due to the potential
cumulative risk that may exceed EPA's goals for remedial action. Once all levels are achieved, a risk assessment
will be performed to determine protectiveness. Table K-l in Appendix K compares the groundwater cleanup
levels to current MCLs. There have been no changes to MCLs since the 2010 AROD. As indicated earlier, the
state AGQS for arsenic has been updated from 10 (ig/L to 5 (ig/L. During this FYR period, three residential wells
have intermittently exceeded the updated state AGQS but have been below the MCL and State AGQS cited as the
interim arsenic groundwater cleanup level.
The soil cleanup levels in the 1991 ROD were established based on the potential for soils to leach contamination
into groundwater. They reflect levels that were not expected to impair future groundwater quality above the
interim groundwater cleanup levels. To determine if the soil cleanup levels remain protective of direct human
exposures, Table K-2 in Appendix K compares the soil cleanup levels to current EPA RSLs. All soil cleanup
levels, based on a residential exposure scenario, demonstrate that they correspond to risks within EPA's risk
management range.
Manganese (State)
In March 2021, NHDES revised the AGQS for manganese from 840 to 300 (ig/L. Manganese is not currently
listed as a COC for the Site. Seven on-site monitoring wells set in overburden or shallow bedrock intervals have
exhibited AGQS exceedances for manganese. Exceedances of manganese are almost all in source area monitoring
wells that exhibit reducing conditions and also exhibit exceedances of the AGQS for arsenic. Institutional controls
are in place in the form of the GMZ and a restrictive covenant to restrict groundwater use at the Site and the area
around the Site. This has eliminated known exposure pathways and the remedy remains protective for manganese.
Arsenic (State)
In July 2021, NHDES modified its Ambient Groundwater Quality Standard (AGQS) for arsenic from 10 (ig/L (10
ppb) to 5 (ig/L (5 ppb). The current groundwater clean-up level at Mottolo is 10 (ig/L which equates to a
carcinogenic risk of 5.17xlO"02 (ig/L which is not within EPA's acceptable 10"6 to 10"4 risk range. Several
monitoring wells immediately downgradient of the former source area exceed this risk range, likely due to
geochemical changes to the groundwater resulting from reductive dechlorination of chlorinated solvents which
mobilized naturally occurring arsenic. However, the combination of a residential water line and institutional
controls prohibiting installation of groundwater wells has eliminated known exposure pathways, and therefore the
remedy remains protective for arsenic.
PFAS (Federal)
In May 2022, EPA issued updated noncancer reference dose (RfD) values for several PFAS compounds which
result in the following RSLs at hazard quotient (HQ) target 0.1:
• PFOA: 6 ng/L (equivalent to parts per trillion [ppt])
• PFOS: 4 ng/L
• PFNA: 6 ng/L
• PFHxS: 40 ng/L
• Hexafluoropropylene oxide dimer acid (HFPO-DA) (Gen-X): 6 ng/L
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The RfD values for PFOA, PFOS, PFNA and PFHxS are based on Agency for Toxic Substances and Disease
Registry (ATSDR) Minimal Risk Levels (MRLs) for ingestion exposure.
The RfD value for HFPO-DA (Gen-X) is based on a chronic oral RfD from EPA Office of Water, which is 3E-06.
In May 2021, EPA issued an updated noncancer RfD for PFBS. PFBS has a chronic oral RfD of 3E-04.
In December 2022, EPA released a new oral RfD of l.OxlO"03 milligrams per kilogram per day (mg/kg-day) for
PFBA based on a new Integrated Risk Information System (IRIS) value. Previously, no RfD was available for
PFBA.
PFAS (State)
In July 2020, New Hampshire promulgated state AGQSs for the following four PFAS:
• PFOA: 12 ppt
• PFOS: 15 ppt
• PFHxS: 18ppt
• PFNA: 11 ppt
Current state law requires that AGQSs be the same value as any MCL established by NHDES, and also that they
be at least as stringent as health advisories set by EPA.
At this time EPA has made no determination of whether these state standards will need to be added as an ARAR
for this Site. They should, however, be used as screening values for PFAS compounds, along with the RSLs. For
purposes of this FYR, EPA has evaluated the PFAS data collected against EPA's RSLs and the state's PFAS
AGQS.
PFAS have been detected above state AGQSs and EPA RSLs in groundwater samples from overburden and
shallow bedrock generally associated with VOC and arsenic plumes. PFAS have not been detected at elevated
concentrations in deep bedrock monitoring wells, residential wells or surface water sample locations,
suggesting that PFAS contamination within the overburden and shallow bedrock downgradient of source areas
generally discharges to Brook A and is attenuated through dilution.
Although there are exceedances of PFOA, PFOS and PFHxS state AGQS and EPA RSLs, the remedy remains
protective because institutional controls are in place, and no one is drinking the groundwater on site. In addition,
residential wells were also sampled, and results were less than EPA RSLs and State AGQS. Overburden
monitoring well MW-104S was sampled for PFAS in groundwater for the first time in 2022 to assess whether
PFAS in overburden groundwater migrates further downgradient beyond well couplet MW-22. PFOA was
detected in the groundwater sample collected from MW-104S at a concentration below the AGQS (12 ng/L) and
2022 EPA RSL (6 ng/L) at 2.60 ng/L.
Surface water samples were also analyzed for PFAS. Currently, no NHDES standards or site-specific screening
levels have been developed for PFAS in surface water. EPA Region 1 established ecological screening values
(ESVs) to support screening-level ecological risk assessments at sites where PFAS have been detected in soils and
surface waters. This FYR Report compared the surface water sampling results to the Region 1 ESVs (Table 8).
There were no exceedances of the Region 1 ESVs.
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PFAS (Summary)
The PFAS results are shown in Figures F-10 through F-12 in Appendix F. Overall the exceedances observed in
the overburden and shallow bedrock monitoring wells were generally consistent with the distribution of the TCE
plume (downgradient of the FDDA and SB A). The presence and location of the PFAS exceedances are likely
related to the industrial chemicals disposed within the FDDA. Institutional controls are in place in the form of
GMZ and a restrictive covenant to restrict groundwater use at the Site and the area around the Site. Due to a lack
of a complete exposure pathway to potential receptors, the remedy is believed to be protective for PFAS
constituents.
1,4-Dioxane (Federal)
Using 2013 updated IRIS toxicity information and the standard Superfund risk assessment approach, EPA's
carcinogenic risk range of 10"6 to 10"4 for 1,4-dioxane equates to a concentration range of 0.46 (ig/L to 46 (ig/L.
1,4-Dioxane (State)
In September 2018, NHDES modified its AGQS for 1,4-dioxane from 3.0 j^ig/L (ppb) to 0.32 (ig/L (ppb).
1,4-Dioxane was sampled at the Site in 2009/2010 and results were below the detection limit (2 (ig/L). The
detection limit is above the current AGQS of 0.32 (ig/L. NHDES plans to analyze for 1,4-dioxane with a reporting
limit lower than the current AGQS.
1,4-Dioxane (Summary)
While the detection limit is below the upper limit on EPA's acceptable risk range (0.46 j^ig/L to 46 (ig/L), it is
above the NHDES AGQS. NHDES plans to analyze samples for 1,4-dioxane with a reporting limit lower than the
current AGQS. Due to a lack of a complete exposure pathway to potential receptors, the remedy is believed to be
protective for 1,4-dioxane.
Floodplain
Federal regulations at 40 CFR Part 6, Appendix A identified in the ROD were withdrawn. Furthermore, these
regulations, and therefore the current CERCLA remedy, only addressed potential floodplain impacts up to the
100-year flood elevation. Current federal floodplain regulations at 40 CFR Part 9 require a greater assessment of
potential floodplain impacts, including preventing the release of contamination from waste management units and
other remedial infrastructure up to the 500-year floodplain elevation. EPA has assessed potential floodplain
impacts from a 500-year flood event on the Mottolo Superfund Site and determined there are unlikely to be
significant impacts which impact the remedy from flood events. While a small section on the northern edge of the
site is within a flood plain, flooding would not impact the former source area and should not be expected to
impact long-term groundwater direction or elevation. EPA has not identified any protectiveness issues at this time
and therefore no recommendations have been included at this time.
Changes in Toxicity and Other Contaminant Characteristics
2023 PFHxA non-cancer toxicity value
In 2023, EPA released anew oral reference dose (RfD) of 5.0xl0~"4 mg/kg-day for Perfluorohexanoic acid
(PFHxA) based on a new IRIS value. Previously, no RfD was available for PFHxA. Due to a lack of a complete
exposure pathway to potential receptors, the remedy is believed to be protective for PFHxA.
2022 cis-l,2-DCE Noncancer Toxicity Value
In October 2022, EPA released a noncancer reference concentration (RfC) of 4.0xl0~"2 milligrams per cubic meter
(mg/m3) for cis-l,2-DCE, based on a provisional peer reviewed toxicity value (PPRTV) screening value.
Previously, no RfC was available for cis-l,2-DCE.
Cis-1,2-DCE is detected in groundwater at the Site with concentrations up to 210 j^ig/L in 2018 (MO-2DR). The
1991 ROD established acleanup level of 70 (ig/L fortotal 1,2-dichloroethylene. The change in the noncancer
toxicity value for cis-l,2-DCE does not affect the protectiveness of the remedy. No one is using contaminated
groundwater and institutional controls are in place and effective to prevent future exposures to contaminated
groundwater.
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2022 PFBA Noncancer Toxicity Value
In December 2022, EPA released a new oral RfD of l.OxlO'"3 mg/kg-day for PFBA based on a new IRIS value.
Previously, no RfD was available for PFBA. The RSL for PFBA is 1.85xl0+u" (ig/L using the RSL calculator.
PFBA has been sampled during the recent PFAS groundwater monitoring events. Detections ranged from 2.08
ng/L to 9.37 ng/L. There was only one detection in residential wells (2.08 ng/L in 2019). Monitoring will
continue, however, due to a lack of a complete exposure pathway to potential receptors and observed
concentrations below the RSL, the remedy is believed to be protective for PFBA.
2022 PFOA Noncancer Toxicity Value
In May 2022, EPA released an updated oral RfD of 3xl0~"6 mg/kg-day for PFOA, based on the ATSDR MRL.
The new value indicates that PFOA is more toxic from noncancer health effects and would result in an increased
noncancer risk.
The maximum detected concentration of PFOA between 2018 and 2022 was 484 ng/L in monitoring well
MO-3SR in 2019, which exceeds the PFOA RSL of 6 ng/L. Several other wells reported concentrations of PFOA
above the RSL. Residential well detections ranged from 2.13 to 3.8 ng/L, which is below the RSL. Groundwater
use on and near the Site is restricted and residential well sampling results are below the RSL. Due to a lack of a
complete exposure pathway to potential receptors, the remedy is believed to be protective for PFOA.
2022 PFOS Noncancer Toxicity Value
In May 2022, EPA released an updated oral RfD of 2xl0~"6 mg/kg-day for PFOS, based on the ATSDR MRL. The
new value indicates that PFOS is more toxic from noncancer health effects and would result in an increased
noncancer risk.
The maximum detected concentration of PFOS between 2018 and 2022 was 203 ng/L in monitoring well MO-
3SR in 2021 and 2022, which exceeds the PFOS RSL of 4 ng/L. Several other wells reported concentrations of
PFOA above the RSL. Residential well results were all below detection (maximum detection limit of 2 ng/L).
Groundwater use on and near the Site is restricted and residential well sampling results are below the RSL. Due to
a lack of a complete exposure pathway to potential receptors, the remedy is believed to be protective for PFOS.
2022 PFNA Noncancer Toxicity Value
In May 2022, EPA released an oral RfD of 3xl0~"6 mg/kg-day for PFNA, based on the ATSDR MRL. Previously,
no RfD was available for PFNA.
The maximum detected concentration of PFNA between 2018 and 2022 was 11 ng/L in monitoring well MO-2S
in 2018, which exceeds the PFNA RSL of 6 ng/L. Residential well results were all below detection (maximum
detection limit of 2 ng/L). Groundwater use on and near the Site is restricted and residential well sampling results
are below the RSL. Due to a lack of a complete exposure pathway to potential receptors, the remedy is believed to
be protective for PFNA.
2022 PFHxS Noncancer Toxicity Value
In May 2022, EPA released an oral RfD of 2.0xl0~"5 mg/kg-day for PFHxS, based on the ATSDR MRL.
Previously, no RfD was available for PFHxS.
The maximum detected concentration of PFHxS between 2018 and 2022 was 180 ng/L in monitoring well MO-
3SR in 2020, which exceeds the PFHxS RSL of 40 ng/L. Several other wells reported concentrations of PFHxS
above the RSL. Residential well results were all below detection (maximum detection limit of 2 ng/L).
Groundwater use on and near the Site is restricted and residential well sampling results are below the RSL. Due to
a lack of a complete exposure pathway to potential receptors, the remedy is believed to be protective for PFHxS.
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2022 HFPO-DA (Gen-X) Noncancer Toxicity Value
In May 2022, EPA released an oral RfD of 3.0xl0"°6 mg/kg-day for HFPO-DA, also known as Gen-X, based on
an oral RfD available from EPA Office of Water. Previously, no RfD was available for HFPO-DA.
HFPO-DA (Gen-X) is not expected to be a potential chemical of concern at the Site based on site history.
2021 PFBS Noncancer Toxicity Value
In May 2021, EPA released an oral RfD of 3x10"04 mg/kg-day, based on an EPA PPRTV (USEPA, 2021a). The
new value indicates that PFBS is more toxic from noncancer health effects and would result in an increased
noncancer risk.
The maximum detected concentration of PFBS between 2018 and 2022 was 19.2 ng/L in monitoring well MO-
3SR in 2022, which is less than the PFBS RSL of 600 ng/L. PFBS was detected in a single residential well in
2020 at 1.93 ng/L, which is less than the RSL. Due to a lack of a complete exposure pathway to potential
receptors, the remedy is believed to be protective for PFBS.
2021 Ethyl Tertiary Butyl Ether (ETBE) Cancer and Noncancer Toxicity Values
In August 2021, EPA finalized a noncancer oral RfD and a noncancer inhalation RfC for ETBE based on new
IRIS toxicity values. Additionally, EPA finalized a value for inhalation unit risk, based on a new IRIS cancer
value. Previously, no toxicity values were available for ETBE.
ETBE is analyzed in residential wells but has never been detected. The detection limit in 2022 was 0.50 (ig/L. The
current EPA RSL is 70 j^ig/L.
2021 tert-Butyl Alcohol (tBA) Cancer and Noncancer Toxicity Values
In August 2021, EPA finalized a noncancer oral RfD and a noncancer inhalation RfC for tBA based on new IRIS
toxicity values. Additionally, EPA finalized an oral slope factor for tBA based on a new IRIS cancer value.
Previously, no toxicity values were available for tBA.
Analysis which included tBA was performed in residential wells, however, it has not been detected.
2021 Updated Recommendations on the Use of Chronic or Subchronic Noncancer Values
In 2021, a memorandum was released from the Office of Land and Emergency Management (OLEM) regarding
the use of subchronic toxicity values rather than the chronic noncancer value for 19 chemicals. This
recommendation is based on OLEM's Human Health Regional Risk Assessment Forum's (OHHRRAF) Toxicity
Workgroup evaluation of the toxicity of 32 chemicals. The OHHRRAF Toxicity Workgroup identified 21 oral
and 11 inhalation noncancer toxicity values where a subchronic toxicity value was lower than its corresponding
chronic toxicity value. After review of relevant information, the OHHRRAF recommended use of the subchronic
toxicity value rather than the chronic value for 19 of the 32 chemicals, as follows below.
• Subchronic inhalation RfC selected for the following chemicals (Chemical Abstracts Service Registry
Number [CASRN]):
o Acrylic acid (79-10-7)
o 2-Ethoxyethanol (110-80-5)
o Ethyl-chloride (75-00-3)
o 2-Methoxyethanol (109-86-4)
• Subchronic oral RfD selected for the following chemicals (CASRN):
o Acrylonitrile (107-13-1)
o Allyl alcohol (107-18-6)
o Atrazine (1912-24-9)
o Bromodichloromethane (75-27-4)
o Cadmium (7440-43-9)
o p-Chloroaniline (106-47-8)
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o p-Cresol (106-44-5)
o Ethyl acetate (141-78-6)
o Ethylbenzene (100-41-4)
o Ethylene glycol (107-21-1)
o Heptachlor (76-44-8)
o Hexachlorobenzene (118-74-1)
o Hexachlorocyclohexane, gamma (58-89-9)
o 1,2,4,5-Tetrachlorobenzene (95-94-3)
OHHRRAF recommended the chronic inhalation noncancer value for the following chemicals: ammonia,
chlordane, 1,1-dichloroethylene, methyl tert-butyl ether, nitromethane and vinyl acetate.
OHHRRAF recommended the chronic oral noncancer value for the following chemicals: acrylamide, acrylic acid,
1,1-biphenyl, cyclohexanone, endosulfan, ethylene glycol monobutyl ether and pentachlorophenol.
This change does not affect protectiveness of the remedy because no one is using contaminated groundwater and
institutional controls are in place and effective to prevent future exposures to contaminated groundwater.
2020 trans-l,2-DCE Noncancer Toxicity Value
In November 2020, EPA finalized a new RfC for trans-1,2-DCE based on a new PPRTV. There previously was
no RfC for trans-1,2-DCE. During this FYR period, trans-1,2-DCE was detected in groundwater at
concentrations up to 40 (ig/L (MW-103D-2 in 2020). The 1991 ROD established a cleanup level of 70 (ig/L for
total 1,2-DCE. The change in the toxicity value for trans-1,2-DCE does not affect the protectiveness of the
remedy. No one is using groundwater contaminated with trans-1,2-DCE and institutional controls are in place and
effective to prevent future exposures to contaminated groundwater. Residential wells near the Site are analyzed
for trans-l,2-DCE and all results have been less than detection. The most recent detection limit in 2022 was 0.50
(ig/L. Due to a lack of a complete exposure pathway to potential receptors, the remedy is believed to be protective
for trans-1,2-DCE.
Lead in Soil Cleanups
EPA continues to examine the science around lead exposure. Updated scientific information indicates that adverse
health effects are associated with blood lead levels (BLLs) at less than 10 micrograms per deciliter (j^ig/dL).
Several studies have observed "clear evidence of cognitive function decrements in young children with mean or
group BLLs between 2 and 8 (ig/dL."
Based on this updated scientific information, EPA is including an evaluation of potential lead risks with a goal to
limit exposure to residential and commercial soil lead levels such that a typical (or hypothetical) child or group of
similarly exposed children would have an estimated risk of no more than 5% of the population exceeding a 5
(ig/dL BLL. This is based on evidence indicating cognitive impacts at BLLs below 10 (ig/dL. A target BLL of 5
(ig/dL reflects current scientific literature on lead toxicology and epidemiology that provides evidence that the
adverse health effects of lead exposure do not have a threshold.
EPA's 2017 OLEM memorandum "Transmittal of Update to the Adult Lead Methodology's Default Baseline
Blood Lead Concentration and Geometric Standard Deviation Parameters" (OLEM Directive 9285.6-56) provides
updates on the default baseline blood lead concentration and default geometric standard deviation input
parameters for the Adult Lead Methodology (ALM). These updates are based on the analysis of the National
Health and Nutrition Examination Survey 2009-2014 data, with recommended updated values for baseline blood
lead concentration being 0.6 j^ig/dL and geometric standard deviation being 1.8.
Using updated default Integrated Exposure Uptake Biokinetic Model and ALM parameters at a target BLL of 5
(ig/dL, site-specific lead soil screening levels (SLs) of 200 parts per million (ppm) and 1,000 ppm are developed
for residential and commercial/industrial exposures, respectively.
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Given the ongoing review of information, the above SLs are considered in this FYR for informational purposes.
Lead was originally assessed as part of the 1990 RI. The maximum concentration of lead found in soil during the
RI phase was 181 ppm, which is below the commercial screening level of 1,000 ppm. In 2009, lead was assessed
again as part of an effort to investigate the potential for residual soil contamination in the FDDA, in the former
piggery operation area, and in the sloped downhill area near the large concrete pad. The maximum concentration
of lead found in soil during the 2009 investigation was 530 ppm, which is still below the commercial screening
level of 1,000 ppm. Currently, there is no risk to human health because the property is not being used for
residential purposes; however, if there are future plans for development for any use other than commercial, lead
may need to be reevaluated to ensure there are no unacceptable risks.
Changes in Exposure Pathways
Evidence exists that there have been minor changes in land use since the previous FYR. A nearby sugar bush
operation has tapped multiple Maple trees on the site, and multiple pieces of evidence were observed that suggest
that the Site is being routinely used for recreational activities (e.g., hunting, hiking) and vandalism. The 1991
baseline risk assessment concluded that the risk posed by the future potential residential use of groundwater from
wells installed within the FDDA could exceed the acceptable cancer risk range. Currently, a GMZ exists that is
inclusive of the Mottolo property and select surrounding properties. Therefore, current exposure to groundwater
within the GMZ is not considered a complete exposure pathway.
During the FYR site inspection, EPA observed taps on several maple trees located on the northern portion of the
Site. This area is near the newly installed wells that will provide data related to the extent of PFAS contamination.
Depending on the results of the ongoing PFAS investigation, additional research may be needed to determine if
groundwater beneath trees where sap is collected is impacted by site contaminants.
Overburden Groundwater Data and Potential VI Pathway
Office of Solid Waste and Emergency Response (OSWER) Directive 9200.2-84 (Assessing Protectiveness at
Sites for Vapor Intrusion: Supplemental Guidance to the Comprehensive Five-Year Review Guidance (EPA
2012d)) provides a recommended framework for considering vapor intrusion (VI) while evaluating remedy
protectiveness in the context of the Superfund FYR process (even if VI was not addressed as part of the original
remedial action). VI was not addressed in the original risk assessment for Mottolo. Residents in areas adjacent to
the FDDA formerly used groundwater from bedrock wells as tap water and some area residents are currently still
using groundwater from bedrock wells at residences adjacent to the Mottolo property during this FYR period.
For the 2013 and 2018 FYRs, groundwater data were collected and reviewed relative to the potential for a
complete VI pathway to exist. Exceedances of EPA target groundwater concentrations for the VI pathway were
noted for 1,1-dichloroethane, TCE and vinyl chloride. However, the exceedances occurred within the FDDA and
there were no buildings located within the FDDA; therefore, the VI pathway was not considered complete under
the current site use conditions. It was noted that the VI pathway may warrant further evaluation if there are future
changes in site conditions.
For the 2023 FYR, groundwater data were reviewed for potential VI issues. According to the most recent
groundwater data collected in fall 2021, there were no detections of site-related VOCs in residential wells.
Exceedances of EPA target groundwater concentrations for the VI pathway were noted in some of the overburden
wells and bedrock wells for certain contaminants including TCE, 1,2-DCE and vinyl chloride. These exceedances
did not occur in any residential wells and there are no buildings currently located on the Site; therefore, the VI
pathway is not considered complete under the current site use conditions. VI may need to be reevaluated if land
use or site conditions change in the future.
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Vapor Intrusion
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 RSLs for toxicity values and physiochemical parameters and is automatically updated during the
semi-annual RSL updates. The User's Guide provides further details on how to use the VISL calculator:
https://www.epa.gov/vaporintrusion/vapor-intrusion-screening-level-calculator.
The vapor intrusion exposure pathway at the Site is currently incomplete. However, if site conditions or land use
change, vapor intrusion may need to be reevaluated.
Ecological Risk Assessment
2021 Development of the Ecological Screening Values (ESVs) for PFAS
ESVs have been developed to support screening-level ecological risk assessments sites where PFAS have been
detected in soils and surface waters. The ESVs, developed for eight PFAS, represent PFAS concentrations in soil
and surface water at or below which chronically exposed biota are not expected to be adversely affected and
ecological risks or other impacts are unlikely.
The ESVs support the screening-level steps (steps 1 and 2 of eight steps) of EPA's Ecological Risk Assessment
Guidance for Superfund and may be applied at sites undergoing investigation for the historic release or disposal of
PFAS, to identify whether PFAS levels pose potential unacceptable ecological risks. Sites that have
concentrations of PFAS that exceed ESVs may require further investigation in a baseline ecological risk
assessment, which in turn may support risk-management decisions and actions to reduce risks. These ESVs are
solely for use in conducting screening-level ecological risk assessments and are not recommended or intended for
use as default cleanup values.
The ESVs were developed for the following media and receptors:
• Soils for invertebrates.
• Soils for plants.
• Soils for avian and mammalian wildlife.
• Surface water for freshwater and marine aquatic biota.
• Surface water for aquatic-dependent avian and mammalian wildlife.
The ESVs can be found in Derivation of PFAS Ecological Screening Values (Grippo et all, 2021).
During 2019, NHDES initiated a surface water screening program to assess the presence and extent of PFAS
concentrations in surface water. Of the 36 PFAS compounds analyzed for, four compounds were detected
in the surface water samples collected, including PFOA, PFOS, PFBA and PFBS.
This FYR Report compared the results to the Region 1 ESVs and there were no exceedances (Table 8).
Expected Progress Towards Meeting RAOs
The 1991 ROD specified the following RAOs (also referred to as response action objectives):
• To eliminate or minimize the threat posed to public health, welfare and environment by the current extent
of contamination of groundwater and soils;
• To eliminate or minimize the migration of contaminations from soils into the groundwater;
• To meet federal and state ARARs;
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Groundwater concentrations continue to exceed cleanup levels in the overburden, shallow and deep bedrock wells
on the Site. COC concentrations are increasing in some overburden and shallow groundwater wells. NHDES
believes this is due to reduction in groundwater withdrawal.
The restoration time to attain the interim cleanup levels in the ROD as amended may likely take longer than
anticipated. Additional data from future sample events will improve the dataset and provide a more
comprehensive assessment of concentration trends in the groundwater and the effectiveness of natural attenuation
to meet the RAOs. A revised cleanup timeframe for groundwater needs to be established based on future sampling
efforts.
QUESTION C: Has any other information come to light that could call into question the
protectiveness of the remedy?
The expected impacts of climate change in New England pose increasing risks to contaminated sites. Increases in
air and water temperature, precipitation, flooding and periods of drought may result in altered fate and transport
pathways and exposure assumptions, impaired aquatic habitats, dispersal of contaminants, damage to remediation
related structures and ultimately, ineffective remedies. At coastal sites, saltwater impacts made more likely by
sea-level rise may cause corrosion of remediation equipment and impair restoration efforts. Increased frequency
of extreme weather events may cause damage or releases at sites, impairing remedial efforts where remedies have
not been adequately designed to protect against these risks.
The risks posed by climate change in New England are not expected to alter the protectiveness of the remedy at
the Mottolo Pig Farm Superfund Site because the former source area is at a significantly higher elevation than the
surrounding area and therefore is unlikely to flood. While there are several permanent and seasonal streams that
run throughout the site, they are largely downgradient and flooding events are unlikely to significantly impact the
overall sitewide remedy or have a long-term impact on groundwater.
VI. ISSUES/RECOMMENDATIONS
Issues/Recommendations
OU(s) without Issues and Recommendations Identified in the FYR:
None
Issues and Recommendations Identified in the FYR:
OU(s): 1
Issue Category: Monitoring
Issue: Manganese and PFAS compounds PFOA, PFOS and PFHxS have been
detected above AGQSs and EPA RSLs on site. Low concentrations of PFOA,
PFHxA, PFBS, PFBA and manganese were detected in some off-site residential
wells at concentrations below the AGQS and EPA RSL and do not exceed the
unacceptable risk threshold.
Recommendation: Continue to monitor and assess potential for risk to receptors
from site COCs and emerging contaminants.
Affect Current
Protectiveness
Affect Future
Protectiveness
Party
Responsible
Oversight Party
Milestone Date
No
Yes
EPA/State
EPA/State
8/13/2028
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OU(s): 1
Issue Category: Remedy Performance
Issue: Based on observed increasing concentrations of TCE and arsenic in some
on-site overburden and shallow bedrock wells, as well as recommendations from
the 2018 assessment of MNA and cleanup times, it is not clear if the long-term
remedy of natural attenuation is performing as intended or predicted.
Recommendation: Determine if natural attenuation is effective in all parts of the
Site and continue to assess natural attenuation processes and groundwater
chemistry to evaluate efficacy and efficiency of natural attenuation. Develop a
regressive analysis using appropriate statistical tools to determine if natural
attenuation will be able to attain groundwater cleanup levels in a reasonable
timeframe.
Affect Current
Protectiveness
Affect Future
Protectiveness
Party
Responsible
Oversight Party
Milestone Date
No
Yes
EPA/State
EPA/State
8/13/2028
OU(s): 1
Issue Category: Monitoring
Issue: PFAS was detected in downgradient monitoring well cluster MW-22.
NHDES installed monitoring wells MW-104 and MW-105 to better delineate
downgradient groundwater contamination, but the results were not available for
this FYR Report.
Recommendation: Once groundwater results are available, determine if
additional wells are needed to further delineate PFAS.
Affect Current
Protectiveness
Affect Future
Protectiveness
Party
Responsible
Oversight Party
Milestone Date
No
Yes
State
EPA/State
8/13/2028
Other Findings
In addition, the following are recommendations that were identified during the FYR, but do not affect current or
future protectiveness:
• Ensure wells are secure.
• Add signage to site identifying it as a Superfund Site with warnings to discourage trespassing and
vandalism
• Determine if the artesian wells should be abandoned.
• Consider removing the former well house to deter trespassing and vandalism.
• There were intermittent exceedances of the NH AGQS for Arsenic in private residential wells over the
past five years, however, there were no exceedances in the past two years of sampling. Continue to
monitor and assess whether Arsenic levels remain below the AGQS.
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VII. PROTECTIVENESS STATEMENT
Sitewide Protectiveness Statement
Protectiveness Determination:
Short-term Protective
Protectiveness Statement:
The remedy at the Site is currently protective of human health and the environment because the source
control component of the remedy has been successfully completed and institutional controls are in place
and currently effective in preventing exposure to contaminated groundwater at the Site and long-term
monitoring of groundwater, surface water and private wells continues. To be protective in the long term,
the following actions need to be taken: Continue to monitor and assess potential for risk to receptors
from site COCs and emerging contaminates; determine if natural attenuation is effective in all parts of
the Site and will be able to attain groundwater cleanup levels in a reasonable timeframe; and once
groundwater results are available, determine if more wells are need to further delineate PFAS.
VIII. NEXT REVIEW
The next statutory FYR for the Mottolo Pig Farm Superfund site is due five years from the completion date of this
review.
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APPENDIX A - REFERENCE LIST
ATSDR. 2021. Toxicological Profile for Perfluoroalkyls. https://www.atsdr.cdc.gov/toxprofiles/tp200.pdf
Balsam Environmental Consultants, Inc. 1990. Mottolo Site Remedial Investigation Report. September 28, 1990.
EPA. 1988. CERCLA Compliance with Other Laws Manual: Interim Final (Part 1). EPA/540/G-89/006. August
1988.
EPA. 1991. Declaration for the Record of Decision. Mottolo Superfund Site. Raymond, New Hampshire. March
29, 1991.
EPA. 1998. Mottolo Superfund Site. Five-Year Review. EPA. September 1, 1998.
EPA. 2003. Second Five-Year Review Report for the Mottolo Pig Farm Superfund Site. Town of Raymond.
Rockingham County, New Hampshire. EPA. September 2003.
EPA. 2008. Third Five-Year Review Report for Mottolo Pig Farm Superfund Site. Town of Raymond,
Rockingham County, New Hampshire. EPA. August 2008.
EPA. 2010. Record of Decision Amendment. Mottolo Pig Farm Superfund Site. Raymond, New Hampshire. EPA.
September 22, 2010.
EPA. 2013. Fourth Five-Year Review Report for Mottolo Pig Farm Superfund Site. Raymond, New Hampshire.
EPA. August 12, 2013.
EPA. 2014. Human Health Evaluation Manual, Supplemental Guidance: Update of Standard Default Exposure
Factors Memorandum. OSWER Directive 9200.1-120.
EPA. 2017. Transmittal of Update to the Adult Lead Methodology's Default Baseline Blood Lead Concentration
and Geometric Standard Deviation Parameters Memorandum, May 17, 2017. OLEM Directive 9285.6-56.
EPA. 2018. Vapor Intrusion Screening Level (VISL) Calculator. Office of Land and Emergency Management,
Office of Superfund Remediation and Technology Innovation (OSRTI), May 2018.
https://www.epa.gov/vaporintrusion/vapor-intrusion-screening-level-calculator
EPA. 2018. Fifth Five-Year Review Report for Mottolo Pig Farm Superfund Site. Raymond, New Hampshire.
EPA. August 13, 2018.
EPA. 2021. Provisional Peer-Reviewed Toxicity Values for Perfluorobutane Sulfonic Acid (PFBS) and Related
Compound Potassium Perfluorobutane Sulfonate. Office of Research and Development, Center for Public Health
and Environmental Assessment. EPA/690/R-21/001F. 2021.
EPA. 2021. Recommendations on the Use of Chronic or Subchronic Noncancer Values for Superfund Human
Health Risk Assessments Memorandum, May 26, 2021. Office of Land and Emergency Management,
Washington, DC. 2021.
EPA. 2021. Human Health Toxicity Values for Hexafluoropropylene Oxide (HFPO) Dimer Acid and Its
Ammonium Salt (CASRN 13252-13-6 and CASRN 62037-80-3) Also Known as "Gen-X Chemicals." Office of
Water, Health and Ecological Criteria Division, Washington, DC, October 2021.
EPA. Integrated Risk Information System (IRIS). Available at https://www.epa.gov/iris
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EPA. Provisional Peer-Reviewed Toxicity Values. Available at https://www.epa.gov/pprtv
EPA. Regional Screening Level Tables. Available at https://www.epa.gov/risk/regional-screening-levels-rsls-
generic-tables
GZA GeoEnvironmental, Inc. 2010. Focused Feasibility Study. Mottolo Pig Farm Superfund Site. Prepared for
New Hampshire Department of Environmental Services and United States Environmental Protection Agency.
GZA GeoEnvironmental, Inc. July 2010.
GZA GeoEnvironmental, Inc. 2016. Site Sampling Data Report. Fall 2015 Site Activities. Prepared for New
Hampshire Department of Environmental Services and United States Environmental Protection Agency - New
England. GZA GeoEnvironmental, Inc. April 2016.
GZA GeoEnvironmental, Inc. 2017. Site Sampling Data Report. Fall 2016 Site Activities. Prepared for New
Hampshire Department of Environmental Services and United States Environmental Protection Agency - New
England. GZA GeoEnvironmental, Inc. January 2017.
GZA GeoEnvironmental, Inc. 2020 Site Sampling Data Report. Fall 2019 Site Activities. Prepared for New
Hampshire Department of Environmental Services and United States Environmental Protection Agency - New
England. GZA GeoEnvironmental, Inc. February 18, 2020.
GZA GeoEnvironmental, Inc. 2021. Site Sampling Data Report. Fall 2020 Site Activities. Prepared for New
Hampshire Department of Environmental Services and United States Environmental Protection Agency - New
England. GZA GeoEnvironmental, Inc. March 8, 2021.
GZA GeoEnvironmental, Inc. 2021. Site Sampling Data Report. Fall 2021 Site Activities. Prepared for New
Hampshire Department of Environmental Services and United States Environmental Protection Agency - New
England. GZA GeoEnvironmental, Inc. April 4, 2022.
GZA GeoEnvironmental, Inc. 2022. Supplemental Work Plan for Supplemental PFAS Assessment Monitoring
Well Installation. GZA GeoEnvironmental, Inc. November 16, 2022.
Hager-Richter Geoscience, Inc. 2010. 3D Geophysical Conceptual Model. Mottolo Pig Farm Superfund Site.
Raymond, New Hampshire. Prepared for: GZA, GeoEnvironmental, Inc. Hager-Richter Geoscience, Inc. July
2010.
Hager-Richter Geoscience, Inc. 2022. Borehole Geophysical Logging - Data Report. Boreholes MW-104DB &
MW-104D. Prepared for: GZA, GeoEnvironmental, Inc. Hager-Richter Geoscience, Inc. October 2022.
Hager-Richter Geoscience, Inc. 2022. Borehole Geophysical Logging - Data Report. Boreholes MW-105D.
Prepared for: GZA, GeoEnvironmental, Inc. Hager-Richter Geoscience, Inc. December 2022.
M. Grippo, J. Hayse, I. Hlohowskyj, and K. Picel. 2021. Derivation of PFAS Ecological Screening Values,
Environmental Science Division, Argonne National Laboratory. September 2021.
Underwood Engineers. 2013. Remedial Action Report. USEPA & NHDES: Hazardous Waste Division. Mottolo
Water Main Extension. Underwood Engineers. April 29, 2013.
A-2
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APPENDIX B - SITE CHRONOLOGY
Table B-l: Site Chronology
Event
Date
Pig fanning took place on site
1960s-1975
Waste disposal took place on site
1975-1979
The New Hampshire Water Supply and Pollution Control Commission started
investigating the Site
1979
EPA implemented a removal action, which included excavation, staging and removal of
soil and drums
1980-1981
EPA proposed the Site to the NPL
April 1985
EPA listed the Site on the NPL
July 1987
The RI/FS is complete and EPA signed the ROD
March 1991
The remedial design is completed
May 1993
Remedial construction began
June 1993
Remedial construction finished
September 1993
The VES system was removed
December 1996
The remedial action is completed
June 1998
EPA completed the Site's First FYR Report
September 1998
The potentially responsible party (PRP) signed a Consent Decree
December 1999
Removal of the chain-link fence, vandal-proofing of monitoring wells and
decommissioning of unused wells took place
Summer 2000
Removal of the interceptor trench and liner took place
Fall 2001
O&M responsibilities transferred to NHDES
2003
EPA completed the Site's Second FYR Report. Surface water sampling was terminated.
September 2003
NHDES sampled the first Strawberry Lane residential well
June 2003
NHDES began quarterly sampling for five residences on Strawberry Lane
March 2004
NHDES issued the PRP a GMZ permit
January 2008
EPA completed the Site's Third FYR Report
August 2008
Residential well sampling results find off-site migration of site contaminants. NHDES
provided bottled water to up to 12 residences
July 2009
NHDES completed the FFS
July 2010
EPA signed an AROD supplementing the 1991 ROD by adding a water main extension
of the Raymond water supply
September 2010
EPA awarded NHDES a cooperative agreement for the waterline construction
May 2011
The waterline construction started
November 2011
The waterline construction attained substantial completion
August 2012
The Town of Raymond adopted an ordinance to restrict groundwater withdrawals within
a newly established GMZ
April 2013
EPA completed the Site's Fourth FYR Report
August 2013
An activity and use restriction for the Mottolo Site is recorded
October 2013
The Technical Memorandum - Evaluation of Potential Aquatic Risk in Brook A is
prepared
March 2016
EPA completed the Site's Fifth FYR Report
August 2018
NHDES contractor decommissions monitoring well MW-S9 located on private property
June 2021
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APPENDIX C - SITE MAP
Figure C-l: Conceptual Site Model1
1 Source: 2021 Site Sampling Report.
NOTES:
1} BASE MAP DEVELOPED USING:
A) BALSAM ENVIRONMENTAL CONSULTANTS. INC. SiTE PLAN "IT fD "SITF AREA
GROUND WATER tc SURFACE WATER/SEDIMENT SAMPLING LOCATIONS", DATED
7/* 9/93. DRAWING No. 2-12.
B) NUDES GIS FIGURE. TILLED "MOTTOLO ":C I ARM SUPERFUNO SITt, RAYMOND,
NEW HAMFSHIRE"
C). RAYMOND 1AX MAP 6, PLOT DAIA 4//i/Ob.
2) THE DISSECTION Q~ GROUNDWATER FLOW A1.0NG BEDROCK FRACTURE PIANES
LIKELY VARIES FROM THE DIRECTION OF REGIONAL GROUNDWATER FLOW.
3) THE GENERAL LOCATION OF TXPJRES DEPICTED ARE CONCEPTUAL.
A B
/ nJ^--102D
MOTTOLO PIG FARM SUPERFUND SITE
BLUEBERRY HILL ROAD
RAYMOND, NH
CONCEPTUAL HYDROGEOLOGIC MODEL
OF SITE AND VICINITY
MW-10OD
- O W-2DR
OW-4SR
IFGFND
DIRECTION O" REGIONAL
GROUNDWATER FLOW IN
BEDROCK
INFERRED DIRECTION Or
OVERBURDEN
GROUNDWATER -LOW
STREAM FLOW
RESIDENTIAL BEDROCK
WATER SUPPLY WEI 1
SHAl_0W BEDROCK WL'__
DEEP BEDROCK WELL
WEA" HE RED BEDROCK
SURFACE
PRIMARY BEDROCK
FRACTURE
SECONDARY BEDROCK
FRACTURE
OVERBURDEN
BEDROCK
DIP A7 MUTh ROSE DIAGRAM OF FRACTURES
Azimuth - Absolute (Count)
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3/23/23, 12:45 PM
APPENDIX D - EPA NEWS RELEASE
EPA to Review Cleanups at Six New Hampshire Superfund Sites this Year | US EPA
An official website of the United States government
United States
Environmental Protection
Agency
MENU
Search EPA.gov
News Releases: Region 01
CONTACT US
EPA to Review Cleanups at Six
New Hampshire Superfund
Sites this Year
January 18,2023
Contact Information
Jo Anne Kittrell (kittrell.joanne@epa.gov)
(617) 918-1822
BOSTON (Jan. 18, 2023) - The U.S. Environmental Protection Agency (EPA) will
conduct comprehensive reviews of completed cleanup work at six National Priority List
(NPL) Superfund sites in New Hampshire this year.
The sites will undergo a legally required Five-Year Review to ensure that previous
remediation efforts at the sites continue to protect public health and the environment.
"Throughout the process of designing and constructing a cleanup at a hazardous waste
site, EPA's primary goal is to make sure the remedy will be protective of public health
and the environment, especially for communities that have been overburdened by
pollution," said EPA New England Regional Administrator David W. Cash. "It is
important for EPA to regularly check on these sites to ensure the remedy is working
properly and New Hampshire communities continue to be protected."
https://Www.epa.gov/newsreleases/epa-review-cleanups-six-new-hampshire-superfund-sites-year
1/5
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3/23/23.12:45 PM
EPA to Review Cleanups at Six New Hampshire Superfund Sites this Year | US EPA
The Superfund Sites where EPA will conduct Five-Year Reviews in 2023 are listed below
with web links that provide detailed information on site status as welt as past
assessment and cleanup activity. Once the Five-Year Review is complete, its findings will
be posted to the website in a final report.
Five-Year Reviews of Superfund sites in New Hampshire to be completed in 2023:
Fletcher's Paint Works and Storage, Milford
Kearsarge Metallurgical Corp., Conway
Keefe Environmental Services, Epping
Mottolo Pig farm, Raymond
South Municipal Water Supply Well, Peterborough
Tibbetts Road, Barrington
More information:
The Superfund program, a federal program established by Congress in 1980,
investigates and cleans up the most complex, uncontrolled, or abandoned hazardous
waste sites in the cou ntry and EPA endeavors to facilitate activities to return them to
productive use. In total, there are 123 Superfund sites across New England.
Superfund and other cleanup sites in New England
EPA's Superfund program
Contact Us to ask a question, provide feedback,
or report a problem.
LAST UPDATED ON JANUARY 18,2023
https://Vww.eps. gw/nwsrele»se5/ep8-wview-cIaanups-six.»ew.h8mp$!iire-$Mperfuncl.9ites-y» 2®
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APPENDIX E - INTERVIEW FORMS
The following questions are being asked to help complete the sixth Five Year Review
(FYR) for the Mottoio Pig Farm Superfund Site in Raymond, NH. If you have any
questions please reach out to the Charlotte Gray at gray.charlotte (5>epa,gov or 617-918-
1243.
Interviewee:
1. What is your overall impression of the project? (general sentiment)
This site is currently being monitored annually. The results show generally decreasing
trends and natural attenuation parameters that continue to be favorable for the natural
attenuation of chlorinated ethenes. There have been extensive geophysical investigations
looking into fracture connectivity at the site in the shallow and deep bedrock. Institutional
controls have restricted groundwater withdrawals from the northwest of the site in the
groundwater management zone. The combination of a solid conceptual site model backed
by geophysics, the existence of institutional controls, continued monitoring of on-site
monitoring wells and annual monitoring of residential supply wells at parcels that abut
the groundwater management zone (GMZ) have continued to demonstrate the
protectiveness of the remedy at this site.
2. Have there been routine communications or activities (site visits, inspections, reporting
activities, etc.) conducted by your office regarding the site? If so, please give purpose
and results.
Annual groundwater sampling events that our consultant conducts in the fall are
summarized in annual reports available on our OneStop Site Document website. These
annual monitoring events consist of groundwater sampling, residential drinking water
supply well sampling for homes that abut the GMZ, and surface water sampling.
Recently, there have been multiple site visits by NHDES to observe the progress of the
ongoing PFAS Remedial Investigation (RT) that includes well drilling, borehole
geophysical measurement, and transducer installation/retrieval. This investigation is
ongoing and will be documented in future reports posted to the above link upon
completion. Results can be found at the following address:
https://www4.des. state. nh.us/DESOnestop/SiteDocuments.aspx?SiteNumber=198704094
3. Have there been any complaints, violations, or other incidents related to the site
requiring a response by your office? If so, please give details of the events and results of
the responses.
There have been no complaints, violations or other incidents that have required responses
from our office.
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4. Is the remedy functioning as expected? How well is the remedy performing?
The remedy has been effective at preventing exposure at the site. Institutional controls
remain in effect. An Activity and Use Restriction (AUR) on the parcel restricts
groundwater withdrawal, activities that disturb contaminated soil, and specific industrial
and commercial activities. In addition, a town ordinance restricts groundwater
withdrawals in an area northwest of the site. Decreasing concentrations of contaminants
and natural attenuation parameter indicators continue to suggest that the Monitored
Natural Attenuation (VINA) remedy is effective at the site. The ongoing PFAS R1 that
includes the installation of monitoring wells to evaluate the potential for bedrock
groundwater to migrate toward drinking water supply wells located north and outside the
town ordinance area may help to provide further verification of the effectiveness of the
remedy.
5, Have any problems been encountered which required, or will require, changes to this
remedial design or this ROD?
In the years since the last FYR was published, NHDES has updated the Ambient
Groundwater Quality Standards (AGQS) for manganese, 1,4-dioxane, PFOS, PFOA,
PFNA, PFHxS, and arsenic. Monitoring wells exhibiting AGQS exceedances for
manganese, PFOS, PFOA, and PFHxS are now present at the site but these compounds
currently do not have ICLs established in the existing ROD. In addition, the lowering of
the standard for arsenic has resulted in the ROD ICL for arsenic being inconsistent with
our AGQS. NHDES believes that these changes to our AGQS should be considered in an
updated ROD with the establishment of ICTs that are equivalent to our AGQS.
6. What does the monitoring data show? Are there any trends that show contaminant
levels are increasing or decreasing?
Concentrations of VOCs and other contaminants of concern (COCs) at the site have been
continuously in decline with the exception of TCE, cis-DCE, VC, and arsenic in
overburden well MOT_MO-2S, cis-DCE in shallow bedrock wells MOT MO-2DR and
MOT_OW-2DR, and TCE in shallow bedrock well MOTOW-2DR Natural attenuation
parameters are consistent with the attenuation of chlorinated ethenes. Wells with
increasing trends are likely due to a decrease in local groundwater withdrawals caused by
the establishment of institutional controls in the GMZ.
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7. Have there been any significant changes in the O&M requirements, maintenance
schedules, or sampling routines in the last five years? If so, do they affect the
protectiveness or effectiveness of the remedy? Please describe changes and impacts.
In the last five years, the ongoing investigation of PFAS at the site has been the most
significant change in the O&M duties at the site. The ongoing PFAS RI will demonstrate
if protectiveness of the remedy is affected.
8. 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.
The presence of PFAS at the site has increased the cost of annual monitoring. A PFAS RI
is currently being supported by an EPA grant but continued O&M monitoring events
including PFAS as an analyte will increase the overall cost of O&M at the site.
9. Have there been opportunities to optimize O&M, or sampling efforts? Please describe
changes and resultant or desired cost savings or improved efficiency.
There have been no notable cost saving opportunities in the sampling efforts at the site.
This site has been in the MNA phase for many years and most of the cost related to O&M
have remained generally unchanged since the previous FYR.
10. Do you have any concerns for emerging contaminants being at the site?
While institutional controls exist that are protective of homes currently in the GMZ, there
is currently an ongoing RI regarding the presence of PFAS on the site. This ongoing
investigation involves the installation of overburden, shallow bedrock, and deep bedrock
monitoring wells that are also designed to serve as sentry wells for the migration of PFAS
offsite to the north and northeast. Borehole geophysics performed on these boreholes and
on a network of nearby deep bedrock monitoring and residential supply wells have
created a solid conceptual site model of the shallow and deep bedrock at and near the site.
While PFAS have been found at concentrations above the AGQS in on-site overburden
and shallow bedrock monitoring wells, to date there have been no AGQS exceedances of
PFAS in deep bedrock wells or nearby residential water supply wells. The continued
investigation of the potential concern of PFAS migration from the site into nearby
residential supply wells will provide insight into the level of concern warranted with
emerging contaminants such as PFAS at the site.
11. Do you have any comments, suggestions, or recommendations regarding the site's
management or operation?
E-3
-------
We do not have any comments, suggestions or recommendations in reference to the site's
management or operation at this time.
E-4
-------
APPENDIX F - DATA REVIEW FIGURES
Figure F-l: Residential Monitoring Locations2
ROAD/PATH
SWALE
INTERMITTENT STREAM
—- BROOKA
fH APPROXIMATE SITE BOUNDARY
APPROXIMATE SOUTHERN BOUNDARY AREA
(SB A)
APPROXIMATE FORMER DRUM DISPOSAL
AREA (FDDA)
Area of Groundwater Use Restriction
PARCELS
>I\) EnoT™^!T!
2 Source: 2021 Site Sampling Report.
F-l
-------
Figure F-2: Monitoring Locations3
SEE INSET
GH5MEHM
CBKKE038 4>
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[2353$®
GS5S89©
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iwea©
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lTocusp.Lan
A- BALSAM ENVIRONMENTAL CONSULTANTS. INC. SITE PLAN TITLED "SITE
AREA GROUND WATER « SURFACE WATER/SEDIMENT SAMPLING
MOTTOLO PIG FARM SUPERFUND SITE
BLUEBERRY HILL ROAD
RAYMOND. NEW HAMPSHIRE
RAYMOND. NEW HAMPSHIRE-
LOCUS AND SITE EXPLORATION PLAN
2. RAYMOND PARCELS AND TOPOGRAPHIC CONTOURS WERE OBTAINED
FROM THE NEW HAMPSHIRE GEOGRAPHICALLY REFERENCED ANALYSIS
AND INFORMATION TRANSFER SYSTEM (NH GRANIT) IN JUNE 2019.
FIGURE
LEGEND:
MW-21S * OVERBURDEN MONITORING WELL
MW-21D « SHALLOW BEDROCK MONITORING WELL
MW-102D •» DEEP BEDROCK MONITORING WELL
sw-s > SURFACE WATER SAMPLING LOCATION
• SITE GATE
ROAD / PATH
SWALE
INTERMITTENT STREAM
—•- BROOK A
SITE OVERVIEW
/
TOPOGRAPHIC CONTOURS 2-FOOT
APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY AREA
(SBA)
APPROXIMATE FORMER DRUM DISPOSAL
AREA (FDDA)
FORMER CONCRETE SLAB
FORMER CONCRETE SLAB (PIGGERY
BUILDING)
I I BUILDING OUTLINE
PARCELS
3 Source: 2022 Site Sampling Report.
F-2
-------
Figure F-3: Overburden Groundwater Elevation Contours, 20224
LEGEND:
¦ * OVERBURDEN MONITORING WELL
SHALLOW BEDROCK MONITORING WELL
DEEP BEDROCK MONITORING WELL
SURFACE WATER SAMPLING LOCATION
. SITE GATE
ROAD/PATH
SWALE
INTERMITTENT STREAM
—- BROOKA
TOPOGRAPHIC CONTOURS 2-FOOT
rH APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY AREA
¦ (SBA)
APPROXIMATE FORMER DRUM DISPOSAL
-- AREA (FDDA)
FORMER CONCRETE SLAB
FORMER CONCRETE SLAB (PIGGERY
1 BUILDING)
I | BUILDING OUTLINE
PARCELS
WINDMERE DRIVE
4 Source: 2022 Site Sampling Report.
F-3
-------
Figure F-4: Shallow Bedrock Groundwater Elevation Contours, 2022s
LEGEND:
MW-21S «, OVERBURDEN MONITORING WELL
WV-21D # SHALLOW BEDROCK MONITORING WELL
MW-102D ^ DEEP BEDROCK MONITORING WELL
sw-3 a SURFACE WATER SAMPLING LOCATION
• » SITE GATE
ROAD/PATH
SWALE
INTERMITTENT STREAM
—«- BROOK A
TOPOGRAPHIC CONTOURS 2-FOOT
APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY AREA
(SBA)
APPROXIMATE FORMER DRUM DISPOSAL
AREA (FDDA)
FORMER CONCRETE SLAB
FORMER CONCRETE SLAB (PIGGERY
BUILDING)
I | BUILDING OUTLINE
I jPARCELS
w INFERRED GROUNDWATER FLOW
DIRECTION
ESTIMATED GROUNDWATER SURFACE
" "" ELEVATION CONTOUR
windmere drive
MW-W4
3
5 Source: 2022 Site Sampling Report.
F-4
-------
Figure F-5: Deep Bedrock Groundwater Elevation Contours, 2022"
LEGEND:
* OVERBURDEN MONITORING WELL
SHALLOW BEDROCK MONITORING WELL
DEEP BEDROCK MONITORING WELL
SURFACE WATER SAMPLING LOCATION
—— SITE GATE
ROAD/PATH
SWALE
INTERMITTENT STREAM
—~- BROOKA
TOPOGRAPHIC CONTOURS 2-FOOT
[~ APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY AREA
(SBA)
- APPROXIMATE FORMER DRUM DISPOSAL
-- AREA (FDDA)
FORMER CONCRETE SLAB
FORMER CONCRETE SLAB (PIGGERY
BUILDING)
I I BUILDING OUTLINE
1 PARCELS
6 Source: 2022 Site Sampling Report.
F-5
-------
Figure F-6: Overburden Groundwater Results, 2022"
LEGEND:
MW.21S « OVERBURDEN MONITORING WELL
MW-21D « SHALLOW BEDROCK MONITORING WELL
MW-102D « DEEP BEDROCK MONITORING WELL
sw-3 , SURFACE WATER SAMPLING LOCATION
• SITE GATE
ROAD / PATH
SWALE
INTERMITTENT STREAM
—BROOK A
TOPOGRAPHIC CONTOURS 2-FOOT
rH APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY AREA
(SBA)
~ - - APPROXIMATE FORMER DRUM DISPOSAL
AREA (FDDA)
FORMER CONCRETE SLAB
I I BUILDING OUTLINE
PARCELS
FORMER CONCRETE SLAB (PIGGERY
BUILDING)
* MW-B40
MW-100D
GATE
Vinyl Chloride <1.0 pg/L
STREAM
t STAFF
MW-22S OCT 2022
TCE 1.5 \iglL
MW-103D-1
MW-103D-2
MW-103D-3
MW-103D-4
OW-2DR
MO-2DR
MO-3DR
MO-3SR
TCE
cis-DCE
Vinyl Chloride
15 (jg/L
9.6 pg/L
<0.5 pg/L
<1.0jjg/L
MW-12S
Source: 2022 Site Sampling Report.
F-6
-------
Figure F-7: Shallow Bedrock Groundwater Results, 20228
MO-2DR
OCT 2022
TCE
13 fjg/L
cis-DCE
98 pg/L
Vinyl Chloride
3.8 pg/L
Arsenic
0.00617 mg/L
MW-22D
OCT 2022
TCE
5.5 pg/L
cis-DCE
27 pg/L
Vinyl Chloride
<1.0 pg/L
Arsenic
0.00152 mg/L
MO-5DR
OCT 2022
TCE
<0.5 pg/L
cis-DCE
5.3 pg/L
Vinyl Chloride
<1.0 pg/L
Arsenic
0.00420 mg/L
MW-12D
OCT 2022
TCE
4.6 pg/L
cis-DCE
34 pg/L
Vinyl Chloride
<1.0 pg/L
is,
Arsenic
0.00912 mg/L
MO-3DR
OCT 2022
TCE
cis-DCE
Vinyl Chloride
v Arsenic
8 Source: 2022 Site Sampling Report.
F-7
-------
Figure F-8: VOC Results, Deep Bedrock Groundwater, 20229
DW-24
\SD
DW-27A OCT 2021
MW-105D
OCT 2022
MW-S6
TCEtm/D
ih-aceipufii
"CffaAj
DW-97
SITE GATE
ROAD I PATH
A. BALSAM ENVIRONMENTAL CONSULTANTS. INC. SITE PLAN TITLED "SITE
AREA GROUND WATER S SURFACE WATER/SEDIMENT SAMPLING
LEGEND:
* OVERBURDEN MONITORING WELL
* SHALLOW BEDROCK MONITORING WELL
MW-1020 * DEEP BEDROCK MONITORING WELL
DW27 • RESIDENTIAL DRINKING WATER WELL
SURFACE WATER SAMPLING LOCATION
fH APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY AREA
(SBA)
- - ¦ APPROXIMATE FORMER DRUM DISPOSAL
AREA (FDDA)
FORMER CONCRETE SLAB
- FORMER CONCRETE SLAB (PIGGERY
^ BUILDING)
I | BUILDING OUTLINE
PARCELS
9 Source: 2022 Site Sampling Report.
F-8
-------
Figure F-9: Arsenic Results, Deep Bedrock Groundwater, 2022"'
10 Source: 2022 Site Sampling Report.
F-9
-------
Figure F-10: PFAS Results, Overburden and Shallow Bedrock Groundwater, 202211
11 Source: 2022 Site Sampling Report.
F-10
-------
Figure F-ll: PFAS Results, Residential Wells, 202212
rH APPROXIMATE SITE BOUNDARY
WETLAND
APPROXIMATE SOUTHERN BOUNDARY
AREA (SBA)
- - - APPROXIMATE FORMER DRUM DISPOSAL
AREA(FDDA)
FORMER CONCRETE SLAB
FORMER CONCRETE SLAB (PIGGERY
BUILDING)
I I BUILDING OUTLINE
I" I PARCELS
12 Source: 2022 Site Sampling Report.
F-ll
-------
Figure F-12: PFAS Results, Surface Water, 202113
13 Source: 2021 Site Sampling Report.
F-12
-------
APPENDIX G - TIME CONCENTRATION PLOTS14
Figure G-l: TCE Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 1
Trichloroethene (TCE) Concentration Trends in Overburden and Shallow Bedrock
Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
9 MOT_
MO-2S
¦ MOT,
MO-2DR
1 MOT,
MO-3SR
^^MOT,
MO-3DR
^M»MOT_
MO-5DR
-•-•MOT,
MW-22D
MOT_
OW-2DR
^^AGQS
Standards
AGQS/CUL
= 5 M-g/L
J ^ ^ ^ ^ ^ J? / / ^ ^ ^ ^ ^
SAMPLING DATE
\\gzabedford\jobs\04Jobs\0190900s\04.0190987.00 - NHDES 2019-2023 Contract\04.0190987.32 - Mottolo 2022 Monitoring - WSA#5\Report\Graphs\04.0190987.32 Concentration Graphs 1 - 7 011923.xlsx
GZA GeoEnvironmental, Inc.
14 Source: 2022 Site Sampling Report.
G-l
-------
Figure G-2: Cis-1,2-DCE Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 2
cis-l,2-Dichloroethene (cis-DCE) Concentration Trends in Overburden and Shallow
Bedrock Groundwater
Mottolo Pig Farm Superfurid Site
Raymond, New Hampshire
600
*sr jr v MOT,
MO-3SR
—^MOT_
MO-3DR
• MOT,
MO-5DR
¦ MOT_
MW-22D
1 MOT_
OW-2DR
AGQS
Standards
AGQS/CUL = 70 ng/L
Note:
The ROD specifies the
contaminant of
concern as Total 1,2
DCE and uses the
more restrictive MCL
Goal of 70 ng/Lfor
Cis-1,2 DCE as the ICL.
There is no AGQS for
Total 1,2 DCE.
\\§zabedford\jobs\MJobs\0190900s\04.0190987.00 - NHDES 2019-2023 Contract\04.0190987.32 -Mottolo 2022 Monitoring - WSA Jt5\Report\Graphs\04.0190987.32 Concentration Graphs 1 - 7 011923.kIsk
GZA GeoEnvironmental, Inc.
G-2
-------
120
100
o
I-
o
u
Figure G-3: Vinyl Chloride Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 3
Vinyl Chloride (VC) Concentration Trends in Overburden and Shallow Bedrock
Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
.& .$> .s? ,jsv .s§> .j? ..*? ..*? \fe 0 & .# .rP .rv>
$9 ^ ^9 ^ ^9 MOT,
.MO-5DR
1 MOT,
.MW-22D
• MOT,
OW-2DR
AGQ.S
Standards
AGQ5/CUL
= 2 M-g/L
SAMPLING DATE
\\gzabedford\jobs\04Jobs\0190900s\04.0190987.00 - NHDES 2019-2023 Contract\04.0190987.32 - Mottolo 2022 Monitoring - WSA #5\Report\Graphs\04.0190987.32 Concentration Graphs 1 - 7 011923.xlsx
GZA GeoEnvironmental, Inc.
G-3
-------
Figure G-4: Arsenic Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 4
Arsenic (As) Concentration Trends in Overburden and Shallow Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
»MOT_MO-2S
• MOT MO-2DR
SAMPLING DATE
\\gzabedford\jobs\04Jobs\0190900s\04.0190987.00 - NHDES 2019-2023 Contract\04.0190987.32 - Mottolo 2022 Monitoring - WSA #5\Report\Graphs\04.0190987.32 Concentration Graphs 1 - 7 011923.xlsx GZ A GeO EnVI TOn menta I, I nC.
G-4
-------
Figure G-5: TCE Concentration Trends, Deep Bedrock Groundwater
Graph 5
Trichloroethene (TCE) Concentration Trends in Deep Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
140
& j? & n* jy J? J? J? J? J> J> & «9 r? „rP n> ri>
^ ^ ^ ^
-------
140
120
100
— 80
|
a.
O
(J
60
40
20
Figure G-6: cis-l,2-DCE Concentration Trends, Deep Bedrock Groundwater
Graph 6
cis-l,2-Dichloroethene (cis-DCE) Concentration Trends in
Deep Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
0 t i L, . , , ¦ 1 -¦ : , T . > l I *-»¦
Jp J? J> J> jy J? J? J? J5 4 £ # J> r? -? & J> J> jy
<$> ^ ^ <<& ^ <<& ^ <
-------
Figure G-7: Arsenic Concentration Trends, Deep Bedrock Groundwater
Graph 7
Arsenic (As) Concentration Trends in Deep Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
0.035
0.025
1—
o
51
\
MW-102D
i—
o
2
~
MW-103D-1
i—
0
2
1
MW-103D-2
1—
0
1
MW-103D-3
^^MOT_
MW-103D-4
¦ MOT,
MW-B31
0
2
1
MW-W4
ROD CUL
Standards
AGQS = 0.005 mg/L
CUL = 0.010 mg/L
Note:
MOT_M W-102D was an
open borehole from 2009
to 2011. During 2011 the
open borehole was
sampled using passive
diffusion bags to
determine the location
for the installation of a
PVC well prior to the
2012 sampling round.
^ <<& ^ ^ ^ ^ ^ ^ ^ ^ ^
SAMPLING DATE
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GZA GeoEnvironmental, Inc.
G-7
-------
Figure G-8: Arsenic Concentration Trends, Residential Wells
Graph 8
Arsenic Concentration Trends in Residential Supply Water
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
0.012
0.01
0.008
t>0
E
z
o
0.006
O
u
0.004
0.002
-i 1-
Jun-09 Jun-10 Jun-11 Jun-12 Jun-13 Jun-14 Jun-15 Jun-16 Jun-17 Jun-18 Jun-19 Jun-20 Jun-21 Jun-22
SAMPLING DATE
»MOT_DW-27/27A
(26 Blueberry Hill Rd)
¦ MOT_DW-24
(1 Randy Ln)
» MOT_DW-9A/9B
(11 Strawberry Ln)
» MOT_DW-22/22A
(16 Huckleberry Rd)
= AGQS
Standards
ROD CUL= 0.010 mg/L
AGQS = 0.005 mg/L
The AGQS decreased from
0.010 mg/L to 0.005 mg/L as
of July 1, 2021.
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04.0190987.32 Graph 8.xlsx
GZA GeoEnvironmental, Inc.
G-8
-------
Figure G-9: PFOA Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 9
Perfluorooctanoic Acid (PFOA) Concentration Trends in Overburden and Shallow
Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
Ann
AGQS = 12 ng/L
EPA RSL = 6 ng/L
u
z
o
u
SAMPLING DATE
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GZAGeoEnvironmental, Inc.
G-9
-------
Figure G-10: PFOS Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 10
Perfluorooctanesulfonic Acid (PFOS) Concentration Trends in Overburden and
Shallow Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
o
5
o
u
250
i MOT,
.MO-2S
¦ MOT.
.MO-3SR
i—
0
2
1
.MW-22S
> MOT.
MW-
12 D
t MOT.
MW-
22 D
• MOT.
OW-2DR
Standards
AGQS = 15 ng/L
EPA RSL = 4 ng/L
Ov o&
SAMPLING DATE
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GZA GeoEnvironmental, Inc.
G-10
-------
Figure G-ll: PFNA Concentration Trends, Overburden and Shallow Bedrock Groundwater
U
z
o
u
Graph 11
Perfluorononanoic Acid (PFNA) Concentration Trends in Overburden and Shallow
Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
01
cc
ro
CD
>
J
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
* 4*
D NJ
V 1,
\ *
\ 6
o6" cf
SAMPLING DATE
eft
MOT_
.MO-2S
—
MOT.
.MO-3SR
—
i—
o
.MW-22S
—
MOT.
.MW-12D
MOT.
.MW-22D
—
h-
o
2
.OW-2DR
Standards
EPA RSL = 5.9 g/L
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GZA GeoEnvironmental, Inc.
G-ll
-------
z
o
J-
z
LU
U
o
u
Figure G-12: PFHxS Concentration Trends, Overburden and Shallow Bedrock Groundwater
Graph 12
Perfluorohexanesulfonic Acid (PFHxS) Concentration Trends in Overburden and
Shallow Bedrock Groundwater
Mottolo Pig Farm Superfund Site
Raymond, New Hampshire
160
140
120
100
80
60
40
20
• MOT.
.MO-2S
¦ MOT.
_MO-3SR
^•MOT.
.MW-22S
t MOT.
.MW-12D
1 MOT.
.MW-22D
—«— MOT.
.OW-2DR
Standards
AGQS = 18 ng/L
EPA RSL = 39 ng/L
ov
SAMPLING DATE
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GZA GeoEnvironmental, Inc.
G-12
-------
APPENDIX H - PFAS DATA REVIEW TABLES
H-l
-------
Table H-l: PFAS Concentrations in Groundwater and Drinking Water Samples15
Pe rf 1 uoroa Iky 1 Ca rbo xy 1 ic Ac id s
Pe rf 1 ud rca 1 ky 1S ulfo nic Acid s
Stratigra phc
unit
Monitoring' We II ID
Sample Date
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g s.
.¦n
-------
Stiatigraphic
Unit
Monitoring Well ID
Sample Date
Fluorote toman;
Pe rfl uo noa 1 ka ne S u Ifo na mide s (FASA s j a r>d S u Ifona mid o Su bsta me s
Pa ra me te r Ca leu bt ions
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CAS
757120-72-4
27619-97-2
391C&34-4
1202S6-6O0
75491-6
4151-502
31506-33-B
1691-992
2444S-C9-7
2991-506
N/A
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3322 1 nter irn E PA Hea Ith Advbo r ies fo r D rin li ing Wa te r * (n^.' L)
ra
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na
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AGQS ' (ng/L)
re
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na
ra
na
ra
na
ra
ra
na
na
ra
Field Samptes
Overb urde n
MCfT_MO-3
Sep-17
ns
ns
(15
AS
ns
ns
ns
26 B
42B.5
74.6%
62.
-------
St ra tig"ra phic
Unit
Monitoring Ullell ID
Sample Date
Perfluorce Ikvlcarboxylc Acids
PerfluDrcslkyl Sulfonic Acids
§
8
B
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t
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CAS
375-234
27C6-903
307-20-4
375-S5-9
335-67-1
375-66-1
355-76-2
2CES-94-B
307-55-1
726S-943
376-C6-7
679C6-19-5
16517-11-6
375-73-5
306-91-4
355-46-4
375-9 2-S
1763-3-1
335-77-3
335-77-3
797BO-39-5
2022 Interim EFA Ha fth Advisor is for Drinking Water * (ng/L)
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0.004
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na
ra
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ra
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ra
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0.02
ra
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EPA Lifetime Drinking Water Health Advisort-s6 (ng/Ll
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ra
na
na
ra
ra
na
na
ra
na
ra
na
ra
2£D0
ra
na
ra
na
ra
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2022EPA P«giona 1 Screening Leveh* (n&'L)
ra
ra
na
na
6
53
na
na
ra
na
ra
na
ra
630
ra
39
ra
4
ra
ra
ra
ACQS ' (r^/L)
ra
ra
na
na
12 1
11 '
na
ra
ra
na
ra
na
ra
ra
ra
IS 1
ra
15 '
ra
ra
re
shalbw
Eted rock
MOT_MW-l 2D
Oct-19
16.3
2.80
Oct- 20
Oct-21
<2Q0
: S
<2.00
s.
<2.00
<200
105
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1 8.
< 2 CO
¦
<2.00
<1.S2
<200
£1.82
3 -
(15
<2.00
<132
<200
.
1J 2
<1.32
<2.00
<1.32
<1.82
<2.00
<1.32
ns
Oct-22
13
2.61 F
MOT_MW- 21D
sep-17
3.6
2.7
2.B
2.7
6.1
(1 ¦
ns
2.0
ns
3.5
flff
ns
NOV-IS
2.4
2.3
2.9
23
5.B
<20
ns
3.2
ns
ns
MOT_MW-22D
Sep-17
2.B
7 E
9 3
190
2.4
6 6
2.1
23
ns
Nov-is
45
43
B5
<2.0
20
/IS
ns
<2.0
ns
3 A
13
Oct-19
<1 ss
2.72
B.12
B.50
173
2 05
2.60
6.59
20.B
Oct-20
<131
2.74
7.37
7.6B
149
•
-'131
131
3.62
3
'
2.36
6.44
21.1
Oct-21
3.IB
7.BB
9.39
1B9
ns
ns
2 43
3.79
9.64
2.00
32.3
ns
Oct-22
2.7B
7.27
9.36
177
2.15
3.27
11.3
3.02
47 .B
MOTOW-2DR
sep-l?
5.6
9.B
20
23
ISO
12
/is
ns
14
ns
61
16
ISO
ns
ns
NOV-IS
3.5
4.9
12
7 8
170
B.4
s
ns
7.7
27
7.B
B9
ns
OCt-19
5.2B
B.77
13.3
11.7
206
= 1 3J
<1 34
- a sa
<134
1 S
<3.65
6.76
11.4
32.2
5.B3
93.4
<1.B4
<134
Oct-20
6.63
13 £
19.7
IB .9
297
2 jOI
<1.94
/is
< 3.3S
9 OB
17
47
9.39
135
NOV-21
7.44
13 2
21.6
21.9
346
12
2B.3
66.1
14
13B F
ns
Oct-22
7.71
142
23.5
23.0
391
2.14
113
22 .B
66.9
12 .B
153
OS
Deep Bedrock
MOT_MW-103D- 2
Sep-17
4.5
B1 Z
17
250
2.0
ns
ns
ns
4fi
ns
ns
Sep-17 DUP
<2.0
<20
= : o
4.B
5.5 Z
110 Z
16
250
2.1
ns
< 2.0
ns
< 2.C
4.7
ns
<20
Nov-13
<2.0
• 20
<2.0
<2.0
4.4
20
70
20 Z
490 Z
4.4 Z
as
ns
<2.0
ns
3.3
ns
< 20
ns
N0V-18 DUP
5.0
2.0
76
12 Z
250 Z
2.3 Z
ns
ns
4.0
ns
MOT_MW- B31
Sep-17
ns
ns
2.1
ns
ns
NOV-IB
2.3
2.3
ns
ns
ns
MOT_MW-S10
Sep-17
ns
ns
3.0
ns
ns
ns
Atov-is
3.0
H-4
-------
Stratigra phic
Unit
Monitoring Well ID
Sample Date
Peril uorcs 1 tricarboxylic Acids
Perflu3rcslky 1 sulfonic Acids
1
§
2
3
1 S
TO
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1
15
1 i
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375-224
27C6-903
307-24^4
375-S5-9
335-67-1
375-E6-1
325-76-2
2133-94-3
307-55-1
7262J-943
376-06-7
679C6-19-5
16517-11-6
375-73-5
2T06-91-4
355-46-4
375-9 2S
1763-23-1
335-77-3
335-77-3
797S 0-39-5
2D22 Interim ERA Hea Ith Advi»ries for Drinking Water1 (n&'L)
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na
na
na
0,004
re
na
re
re
na
re
na
re
re
re
na
re
0.02
re
re
re
EPA Lifetime Drinking Water Health Advoories6 (ng/L)
re
re
na
na
re
re
na
na
re
na
re
na
re
2,000
re
na
re
na
re
re
re
2022 E PA na 1 Sc reen i nE Lweb1® (n&' L)
na
re
na
na
6
53
na
na
re
na
re
na
re
600
re
39
re
4
re
re
re
ACQS1 (re/L)
re
re
na
na
12 '
11 '
na
re
re
na
re
na
re
re
re
IS 1
re
15 1
re
re
re
Residential
supply Wells
(Deep Bedrock
MOT_DW-5
ndv-17
AS
ni
ns
.15
Dec-lS
vis
ns
ns
/I5
Oct-19
<130
SI
: :'
<1.30
<1 .SO
; : '
<1.30
1 '
3
<3;6l
<1.80
K
a K
1 :
<1.80
Oct-20
Oct-21
<2.00
-2.00
« 200
2.00
.15
fl5
136
<13 6
<1 as
<1.36
-i as
<1.34
<1 34
<134
<134
<1.84
<1 54
<1.34
<1,S4
Oct-20
2.04
2.16
133
Oct-21
H5
ns
Oct-22
MOT_DW- 24
NOV-17
ns
ns
.15
05
ns
NOV-IS
ns
Oct-19
•i 36
1
: i6
'
1
'
CKt-20
Oct-21
<2.00
<200
- 2joq
< 2 .CO
< ZOO
-200
ns
f\S
<200
-2.CC
' 2. CO
Oct-22
ns
MOT_DW-27A
NOV-17
*2,0
2.3
ns
ns
ns
.15
NCW-17 DUP
<2.0
- 2.0
•: i
: 2.0
ns
ns
<2.0
ns
- 2.0
AS
- 20
ns
NOV-IS
3.7
ns
ns
,15
n5
.15
Ncw-lS DUP
<2.0
<20
< 2.0
< 2.0
3.B
20
<2,0
? Z o
<20
< 2 0
ns
<20
ns
< 2.0
< 2 O
<2 0
ns
<2.0
Oct-19
3.19
Oct-19 DUP
3.29
Oct-20
<1 39
<1.35
-------
stratigraphic
Unit
Monitoring Well ID
Sample Date
Fluorote brrere
PerfluDioalkaneSulfonamides (FASAs)and sutfonamidoSubslarKes
Parameter Ca leu bt ions
a
1
M
I
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P
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1 £
2 £.
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11
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13
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1
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CAS
757 1 24-7 2-4
27619-97-2
391C&34-4
12022-600
754-91-6
4151-502
31506-32-8
1691-99-2
2444S-C9-7
2991-506
N/A
N/A
N/A
N/A
2022lnterirn EPA Hca fth Advbarta for Drinking Water* (ng^l)
ra
na
rH
ra
ra
ra
na
ra
na
ra
70
na
na
ra
EPA Lifetime Drinking Water Health Advhories' fng/L)
ra
ra
ra
na
ra
ra
na
ra
na
ra
na
na
na
ra
2022 EPA Regbna I Screening Levels* Ing-'L'I
ra
IB
ra
na
ra
ra
na
ra
na
ra
na
na
na
ra
AGQ5 ' (ng/L)
m
ra
ra
ra
ra
na
ra
na
ra
ra
na
na
Reside rrtial
supply Wells
(Deep Bedrock
MOT_DW-5
NOV-17
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
Dec-lS
ns
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
Oct-19
¦ S
<1.30
<4.51
. 8 ?
328>0
<130
<451
1.30
<130
N/A
N/A
N/A
Oct- 20
<194
N/A
N/A
N/A
Oct-21
<200
<2.00
<2.00
ns
<2.CO
ns
ns
ns
ns
<200
N/A
N/A
N/A
Oct- 22
ns
ns
<1S1
N/A
N/A
N/A
MOT_DW-9A
MDV-17
<4.Q
<40
<40
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
Nov-IS
<40
ns
<40
ns
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
Oct-19
<44.3
<44.3
2.34
2.3
100.0%
lGO.C%
Oct- 33
¦ at
a
<4.66
<13 6
<13 6
<186
<466
<1 86
2.13
2.1
100.CW
100.0%
Oct-21
ns
ns
ns
ns
<200
OO
N/A
N/A
Oct- 22
<1.79
ns
,15
2.34
2.34
lOO.CSi
1CO.O%
MDT_DW-22ft
NOV-17
ns
ns
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
NDV-1S
ns
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
Oct-19
-
10.0
532
<4.€a
<1.34
<18.4
j
<461
<134
15.3
N/A
N/A
Oct-3D
<4.155
<136
2,16
52.6
100.CM
41%
Oct- 21
ns
ns
ns
< 2O0
0.0
N/A
N/A
Oct- 22
<1SZ
<133
00
N/A
N/A
IV)DT_DW- 24
Nov-17
«4Q
<40
<4.0
N/A
N/A
N/A
NOV-IS
<40
ns
ns
<4.0
N/A
N/A
N/A
Oct-19
SJ 5 6
<1.36
<1.86
<4 66
<1.86
<136
<18.6
<46.6
<46.6
1 Si
<136
N/A
N/A
N/A
Oct-20
<4.72
2.30
<472
<472
<139
2.3
N/A
N/A
Oct- 21
<2.00
ns
ns
ns
A3
<200
0.0
N/A
N/A
Oct- 22
ns
<132
0.0
N/A
N/A
WOT_DW-27A
NDV-17
ns
ns
ns
ns
2.3
2.3
100.0%
ico.cflfi
Nov-17 DUP
AS
<4.0
ns
<40
ns
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
NOV IS
ns
ns
ns
ns
ns
ns
3.7
3.7
100.0%
ICO.0%
Nov-lS DUP
<4.0
<40
ns
<40
ns
ns
ns
ns
ns
3.B
3.B
100.0%
100.C%
Oct-19
<4.54
<45.4
<454
3.19
32
1000%
1000%
Oct-19 DUP
B4.6
<17.9
-.7 9
<44.8
3.29
B7.9
100.0%
3.7%
Oct-20
<139
<1.89
<1 39
<4.73
<139
<13 9
<189
<47 2
<472
¦=.13 9
2.41
2.4
100.CB&
1000%
Oct-20 DUP
2,24
2.2
100.0%
100.0%
Oct- 21
<200
<2.00
ns
ns
ns
ns
ns
< : 00
2,66
2.7
ioo.cw
100.C%
Oct- 21 DUP
ns
ns
ns
ns
ns
2.72
2.7
ico.c%
ico.c%
Oct- 22
ns
ns
2.79
2.79
100.0%
1000%
Oct-22 DUP
AS
ns
(13
2.90
2.90
ICO.0%
1000%
WDT_D W-9 7
NDV-17
ns
ns
ns
ns
ns
ns
ns
<4.0
N/A
N/A
N/A
Oct-19
<1.32
<1.82
<454
<1.82
-•1.82
3.40
5.5
1000%
62.C%
Oct-20
<135
<1 35
<1:85
^1S5
<463
3,66
75
100.C%
48.6%
Oct-21
ns
2.41
24
ioo.c%
100.C%
Oct-22
ns
ns
2.49
2.49
100.0%
100.0%
H-6
-------
Parfluoroa Ikyl ca rboxylc Acfcis
Pe rf 1 uo res 1 ky 1 s ulfo nic Acid s
stratigia phic
unit
Monitoring Well ID
Sample Date
1
8
§
i
3
1 S
T3
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1
h
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<
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CAS
375-22 A
27G6-903
307-24-4
375-B5-9
335-67-1
375-S6-1
335-76-2
335S-94-3
307-55-1
726 »9«
376-06-7
679C6-19-5
16517-11-6
375-73-5
2706-91-4
355-46-4
375-9 2-S
1763-23-1
335-77-3
335-77-3
797BO-39-5
3322Interim EBX Has Ith Advissrie!
for Drinking Water1 (ng/L)
ra
ra
na
na
0.004
ra
na
ra
ra
na
ra
na
ra
ra
ra
na
ra
0.02
ra
ra
ra
EPA Lifetime Drinking Wate
Health Advisories' fng/L)
ra
ra
na
na
ra
ra
na
na
ra
na
ra
na
ra
2000
re
na
ra
na
ra
ra
ra
2022EPA R/:gk>na IScreening bwefe" (ng/L)
re
ra
na
na
6
5 5
na
na
ra
na
ra
na
ra
600
ra
39
ra
4
ra
ra
ra
ACQS 1 (ri/L)
ra
ra
na
na
12 '
11 '
na
ra
na
na
ra
na
ra
ra
ra
IS 1
ra
15 1
ra
ra
ra
field Qialitv Control Samples
FIELD BLANK- BERGEN
Oct-2 2
AS
n-s
ns
FIELD BLANK - MURPHY
Oct- 22
ns
(15
ns
FIELD BLANK - FULTON
Oct- 22
<1.77
?
-
:
<1.77
- t
<1.77
I n
ns
¦
-
¦
ns
EQUIP BLANK
Oct-2 2
Stratigraphic
Unit
Monitoring Well ID
Sample Date
Fluorote tamers
Perf 1 uoroa 1 kane Sulfonamides (FASAs)a nd Sulfonamido Substances
ParameterCalcutat ions
2
E
£
3
VI
g
O
»
Q
If
IN "
it A
2
E
&
Zl
Vi
i
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9
3 »
— u_
IN —
tb ®
E
&
3
W
g
o
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2
S W
n P4
- -M-
-------
TABLE KEY:
PFAS = per- and polyfluoroalkyl substances
[4] = Number of fluorinated carbon chains for perfluorinated carboxylic acids
[4S] = Number of fluorinated carbon chains for perfluorinated sulfonates
AGQS = Ambient Groundwater Quality Standards included in Env-Or 600 - Contaminated Site Management (Env-Or 603.03)
no = no current standard available
ns - not sampled
N/A = not applicable
ND =not detected above the laboratory reporting limit
J = estimated concentration qualified by the laboratory (NHDES/NHDPHS, EPA, ARA or Microseeps) or by the Environmental Data Services, see laboratory report for explanation
Q = indicates that the concentration has been qualified by the laboratory, see laboratory report for explanation
< = analyte not detected above the laboratory reporting limit
Z = estimated concentration qualified by GZA, based on the Relative Percent Difference (RPD) being outside the acceptance criteria (Refer to Table 8)
F = estimated maximum concentration by the laboratory (Alpha), see laboratory report for explanation
B = indicates the analyte was detected above the reporting limit in the associated method blank, see laboratory report for further explanation
ng/L = nanograms per liter
Bold indicates that the concentration was detected above the laboratory reporting detection limit
Blue shading indicates the concentration exceeds the 2022 EPA Interim Drinking Water Health Advisories
Grey shading indicates the concentration exceeds the New Hampshire MCL/AGQS and the 2022 EPA Regional Screening Level (if applicable) with the exception of PFHxS
Green shading indicatesthe concentration exceeds the 2022 EPA Regional Screening Level (if applicable)
Orange shading indicates the most recent round of sampling data
GENERAL NOTES:
* GZA collected the 2017 and 201S samples for PFAS analysis and submitted the samples to ARA's subcontract laboratory Maxxam
of Mississauga, Ontario, Canada foranalysis by US EPA Method 537 (modified) with isotope dilution.
* GZA collected the 2019-2022 samples for PFAS analysis and submitted the samples to Alpha Analytical of Mansfield, Massachusetts
for analysis by US EPA Method 537 (modified) with isotope dilution,
* All concentrations reported in nanograms per liter (ng/L) which are roughly equivalent to parts per trillion (ppt).
* Values in light gray are less than the Reporting Limit, as indicated by a "<" symbol preceding the Reporting Limit value.!
SPECIFIC NOTES:
1. Effective July 23, 2020, New Hampshire established AGQS for PFOA (12 ng/L), PFOS (15 ng/L), perfluorononanoic acid (PFNA, 11 ng/L), and perfluorohexane sulfonic acid (PFHxS, 18 ng/L).
2. Maxxam reported the 2017 PFOS results in the sulfonate form. In order to calculate the sulfonic acid form of PFOS to compare to the AGQS, the PFOS sulfonate results were multiplied
by a factor of 1.0020.
3. Prior to 2019, a total of nineteen PFAS compounds were measured by the analyses. Beginning in 2019, a total of thirty-six (36) PFAS compounds were measured by the analyses.
Other PFAS compounds may or may not be present.
4. During June 2022, EPA issued updated Interim Drinking Water Health Advisories (EPA Health Advisories) levels for PFOA (0.004 ng/L) and PFOS (0.02 ng/L). Additionally, EPA
issued final Lifetime Drinking Water Health Advisories for PFBS at 2,000 ng/L.
5. Beginning in 2021, the groundwater and drinking water samples were analyzed using a shortened PFAS list consisting of 25 PFAS compounds (listed in Table 1) as approved by NHDES
and in accordance with historical PFAS detections
6. In May 2022, EPA issued new Regional Screening Levels for PFOA, PFOS, PFNA, PFBS, and PFHxS forTap Water based on a Noncancer Child Screening Level Hazard Index of 0.1.
H-8
-------
Table H-2: PFAS Concentrations in Surface Water Samples16
Carboxylic Acids
Sulfonic Acids
Parameter Calculations
£
LL
CL
T5
<
TJ
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<
(D
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dl
S
LL
CL
(ft
<
CL.
Stratigraphic
Unit
Monitoring Well ID
Sample Date
T3
(0
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(0
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-Q
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0- ^
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-fluorooctanoic Acid
:OA) [8]
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£ St.
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CAS
375-22-4
2706-90-3
307-24-4
375-85-9
335-67-1
375-73-5
1763-23-1
N/A
N/A
N/A
N/A
MOT_SW-l
Oet-19
1.96
2.51
2.85
2.51
7.3
100.0%
34.3%
Oct-21
3.12
2.58
2.85
1.92
4.57
3.92
4.57
19.0
100.0%
24.1%
Oct-19
4.87
2.80
4.87
7.7
100.0%
63.5%
MOT_SW-2
Oct-19 DUP
4.81
2.86
4.81
7.7
100.0%
62.7%
Surface Water
Oct-21
3.14
2.58
2.88
2.10
7.30
3.90
2.44
9.74
24.3
74.9%
40.0%
Oct-21 DUP
3.22
2.39
3.02
2.08
7.32
4.06
2.54
9.86
24.6
74.2%
40.0%
MOT_SW-3
Oct-19
6.53
2.89
4.25
10.8
13.7
60.6%
78.9%
Oct-21
3.18
2.45
3.05
2.24
8.05
3.94
2.99
11.0
25.9
72.9%
42.6%
MOT_SW-100
Oct-19
2.09
5.01
2.47
2.12
7.13
11.7
70.3%
61.0%
Oct-21
2.59
2.25
2.75
1.99
8.23
3.28
2.99
11.22
24.1
73.4%
46.6%
Field Quality Control Samples
See Table 6A
TABLE KEY:
PFAS= per-arid polyfluoroalkyl substances
[4] = Number of fluorinated carbon chains for perfluorfnated carboxyli'c acids
[4S] = Number of fluorinated carbon chains for perfluorinated sulfonates
ns = not sampled
N/A = not applicable
ND =not detected above the laboratory reporting limit
< = analyte not detected above the laboratory reporting limit
ng/L = nanograms per liter
Bold indicates that the concentration was detected above the laboratory reporting detection limit
Orange shading indicates the most recent round of sampling data
GENERAL NOTES:
* GZA collected the 2019 and 2021 samples for PFAS analysis and submitted the samples to Alpha Analytical of Mansfield, Massachusetts
for analysis by US EPA Method 537 (modified) with isotope dilution.
* All concentrations reported in nanograms per liter (ng/L) which are roughly equivalent to parts per trillion (ppt).
* Values in light gray are less than the Reporting Limit, as indicated by a "<" symbol preceding the Reporting Limit value.0
* Record of Decia on cleanup standards or New Hampshire surface water quality criteria have not been established for any PFAS.E
16 Source: 2021 Site Sampling Report.
H-9
-------
APPENDIX I - SITE INSPECTION CHECKLIST
FIVE-YEAR REVIEW SITE INSPECTION CHECKLIST
I. SITE INFORMATION
Site Name: Mottolo Pig Farm Superfund Site
Date of Inspection: 2/13/2023
Location and Region: Raymond. New Hampshire.
Region 1
EPA ID: NHD980503361
Agency, Office or Company Leading the Five-Year
Review: EPA
Weather/Temperature: Sunny. 30s
Remedy Includes: (Check all that apply)
~ Landfill cover/containment
Access controls
Institutional controls
~ Groundwater pump and treatment
~ Surface water collection and treatment
Q Other:
1^1 Monitored natural attenuation
~ Groundwater containment
~ Vertical barrier walls
Attachments: Q Inspection team roster attached
~ Site map attached
II. INTERVIEWS (check all that apply)
1. O&M Site Manager
Name
Interviewed ~ at site ~ at office ~ by phone
Problems, suggestions ~ Report attached:
Title
Phone:
Date
2. O&M Staff
Name
Interviewed ~ at site ~ at office ~ by phone
Problems/suggestions ~ Report attached:
Title
Phone:
Date
3. Local Regulatory Authorities and Response Agencies (i.e., state and tribal offices, emergency
response office, police department, office of public health or environmental health, zoning office,
recorder of deeds, or other city and county offices). Fill in all that apply.
Agency
Contact
Name
Problems/suggestions ~ Report attached:.
Title
Date
Phone No.
Agency
Contact Name
Problems/suggestions ~ Report attached:.
Title
Date
Phone No.
Agency
Contact
Name Title
Problems/suggestions ~ Report attached:
Date
Phone No.
Agency
Contact
Name Title
Problems/suggestions ~ Report attached:
Date
Phone No.
Agency.
1-1
-------
Contact
Name Title
Problcms/suaacstions |~~| Report attached:
Date
Phone No.
4.
Other Interviews (optional) 1 1 Report attached:
III. ON-SITE DOCUMENTS AND RECORDS VERIFIED (check all that apply)
1.
O&M Documents
1^1 O&M manual ^ Readily available
Up to date
~ n/a
1 1 As-built drawings EH Readily available
1 1 Up to date
IEIn/a
~ Maintenance logs EH Readily available
~ Up to date
IEI N/A
Remarks:
2.
Site-Specific Health and Safety Plan
Readily available
1^1 Up to date EH N/A
~ Contingency plan/emergency response plan
~ Readily available
~ Up to date £<
| N/A
Remarks:
3.
O&M and OSHA Training Records
Remarks:
~ Readily available
~ Up to date E
|N/A
4.
Permits and Service Agreements
~ Air discharge permit
~ Readily available
~ Up to date £<
| N/A
~ Effluent discharge
~ Readily available
~ Up to date ^
I N/A
~ Waste disposal, POTW
~ Readily available
~ Up to date E
|N/A
I"! Other Dcrmits:
1 1 Readily available
1 1 Up to date £<
|N/A
Remarks:
5.
Gas Generation Records
Remarks:
~ Readily available
~ Up to date ^
I N/A
6.
Settlement Monument Records
Remarks:
~ Readily available
~ Up to date £<
| N/A
7.
Groundwater Monitoring Records
Readily available
1^1 Up to date EH N/A
Remarks:
8.
Leachate Extraction Records
~ Readily available
EH Up to date £<
| N/A
Remarks:
9.
Discharge Compliance Records
~ Air EH Readily available
~ Up to date
M N/A
~ Water (effluent) EH Readily available
~ Up to date
IEIn/a
Remarks:
10.
Daily Access/Security Logs
~ Readily available
EH Up to date E<
I N/A
1-2
-------
Remarks:
IV. O&M COSTS
1. O&M Organization
1 1 State in-house
1^1 Contractor for state
1 1 PRP in-house
1 1 Contractor for PRP
I~1 Federal facility in-house
1 1 Contractor for Federal facility
n
2. O&M Cost Records
1 1 Readily available
1 1 Up to date
1 1 Funding mechanism/agreement in place ^ Unavailable
Orieinal O&M cost estimate:
1 1 Breakdown attached
Total annual cost by year for review period if available
From: To:
1 1 Breakdown attached
Date Date
Total cost
From: To:
1 1 Breakdown attached
Date Date
Total cost
From: To:
1 1 Breakdown attached
Date Date
Total cost
From: To:
1 1 Breakdown attached
Date Date
Total cost
From: To:
1 1 Breakdown attached
Date Date
Total cost
3. Unanticipated or Unusually High O&M Costs during Review Period
Describe costs and reasons:
V. ACCESS AND INSTITUTIONAL CONTROLS
1^1 Applicable ~ N/A
A. Fencing
1. Fencing Damaged ~ Location shown on site map ^ Gates secured ~ N/A
Remarks: No fencins on site. The sate was closed and locked.
B. Other Access Restrictions
1. Signs and Other Security Measures
1 1 Location shown on site map £3 N/A
Remarks:
C. Institutional Controls (ICs)
1-3
-------
1.
Implementation and Enforcement
Site conditions imply ICs not properly implemented Q Yes
IEI
2
O
~
>
Site conditions imply ICs not being fully enforced ~ Yes
IEI No ~ N/A
Tvoe of monitorine (e.g.. self-reoortine. drive b\ ): Inspection
Freauencv: Semiannual
Responsible oartv/aeencv: NHDES
Contact
Name Title Date
Phone no.
Reporting is up to date ~ Yes
~ No IEIn/a
Reports are verified by the lead agency O Yes
~ No |EI N/A
Specific requirements in deed or decision documents have been met ^ Yes
~ No ~ N/A
Violations have been reported O Yes
~ No |EI N/A
Other problems or suggestions: Q Report attached
2.
Adequacy ^ ICs are adequate ~ ICs are inadequate
Remarks:
~ n/a
D.
General
1.
Vandalism/Trespassing ^ Vandalism at multiple locations ~ No vandalism evident
Remarks: Observed damase to cans of new wells MW-104 and MW-105. Trail/ same cameras also
observed on-site. Access to state-owned DroDcrtv is not restricted.
2.
Land Use Changes On Site ~ N/A
Remarks: Several tans were observed on trees on site from a neighboring suearbush.
3.
Land Use Changes Off Site £3 N/A
Remarks:
VI. GENERAL SITE CONDITIONS
A.
Roads ~ Applicable ^ N/A
1.
Roads Damaged ~ Location shown on site map ~ Roads adequate ~ N/A
Remarks:
B.
Other Site Conditions
Remarks:
VII. LANDFILL COVERS ~ Applicable ^ N/A
VIII. VERTICAL BARRIER WALLS ~ Applicable
IE|n/a
IX. GROUNDWATER/SURFACE WATER REMEDIES ^Applicable ~ N/A
A.
Groundwater Extraction Wells, Pumps and Pipelines ~ Applicable
IE|n/a
B. Surface Water Collection Structures, Pumps and Pipelines ~ Applicable
IEI N/A
C.
Treatment System Q Applicable ^ N/A
D. Monitoring Data
1
Monitoring Data
1^1 Is routinely submitted on time ^ Is of acceptable quality
1-4
-------
2
Monitoring Data Suggests:
1^1 Site COCs groundwater plume is effectively ~ Contaminant concentrations are declining
contained; PFAS monitoring ongoing
E.
Monitored Natural Attenuation
1
Monitoring Wells (natural attenuation remedy)
1 1 Properly secured/locked ^ Functioning ^ Routinely sampled Q Good condition
1 1 All required wells located Q Needs maintenance Q N/A
Remarks: New wells (104 cluster and MW-105) had been recently vandalized. NHDES's contractor
returned later the same dav and replaced the damased well caps.
X. OTHER REMEDIES
If there are remedies applied at the site and not covered above, attach an inspection sheet describing the physical
nature and condition of any facility associated with the remedy. An example would be soil vapor extraction.
XL OVERALL OBSERVATIONS
A.
Implementation of the Remedy
Describe issues and observations relating to whether the remedy is effective and functioning as designed.
Begin with a brief statement of what the remedy is designed to accomplish (e.g., to contain contaminant
plume, minimize infiltration and gas emissions).
The source control components of the selected remedv included: (1) excavation and off-site disposal of
1.600 containers of waste and an estimated 160 tons of contaminated soil from the FDD A and SB A; and
(2) installation of a sroundwater interceptor trench and the VES. After three vears. soil results met
cleanup levels and the svstem was turned off in late 1996. All abovesround components of the VES were
removed from the treated area in December 1996. the interceptor trench and liner were removed from the
FDDA in December 2001. and the final VES closeout report was completed durine 1997. The source
control remedial action was considered complete bv EPA on June 28. 1998.
The remainins remedv components include natural attenuation for sroundwater and institutional controls
to prevent consumption of contaminated sroundwater until sroundwater cleanup levels are attained. The
September 2010 AROD added extension of the public water supplv. expanded institutional controls and
expanded off-site sroundwater monitorins reauirements. The extension of the public water supplv
provided safe drinkins water to the 25 affected residences near the Site.
The 1991 ROD indicated that natural attenuation would achieve cleanup standards bv 2004. Further
assessment will be needed to determine if natural attenuation can achieve cleanup standards within a
reasonable period, consistent with EPA suidance standards. PFAS compounds have also been detected
above the AGOSs. EPA health advisory levels and EPA RSLs senerallv co-located with the VOC and
arsenic plumes. NHDES installed new wells in the northern portion of the Site to further delineate PFAS
in sroundwater. Results were not available for this FYR. NHDES is conductins an updated RI to
determine the extent of PFAS in sroundwater and also to establish bedrock sentrv monitorins wells to
monitor for misration of site contaminants bevond the GMZ toward residential supplv wells to the north.
B.
Adequacy of O&M
Describe issues and observations related to the implementation and scope of O&M procedures. In
particular, discuss their relationship to the current and long-term protectiveness of the remedy.
O&M appears adeauate to maintain monitorins wells. While damase was noted durins the inspection.
NHDES's contractor repaired the well cans the same dav.
C.
Early Indicators of Potential Remedy Problems
Describe issues and observations such as unexpected changes in the cost or scope of O&M or a high
frequency of unscheduled repairs that suggest that the protectiveness of the remedy may be compromised
in the future.
Groundwater concentrations are inreasins in some wells. Further evaluation of the natural attenuation
remedy is needed.
D.
Opportunities for Optimization
Describe possible opportunities for optimization in monitoring tasks or the operation of the remedy.
None at this time.
1-5
-------
APPENDIX J - SITE PHOTOGRAPHS
Gate at entrance
Road leading into the Site
J-l
-------
Abandoned well house and graffiti
Approximate area of former pig farm
J-2
-------
Slope down to the FDDA
Example wells and woods
J-3
-------
J-4
-------
Sap collection
Woods and sap lines
J-5
-------
APPENDIX K- REVIEW OF CLEANUP LEVELS
Table K-l: Groundwater Interim Cleanup Level Review
coc
Interim Cleanup
Level
(Ug/L)
Current MCLa
(Mg/L)
Current AGQSb
(fig/L)
Change
Arsenic
10
10
5 (as of 7/1/2021)
No change/more
stringent as of
7/1/2021
TCE
5
5
5
No change
Vinyl chloride
2
2
2
No change
1.1-DCA
81
—
81
No change
Toluene
1,000
1,000
1,000
No change
Ethylbenzene
700
700
700
No change
1.2-DCE (total)
70
^1
O
o
^1
O
o
No change
THF
100
NA
600
Less stringent
1.1.1-TCA
200
200
200
No change
Notes:
~ = not applicable
a. EPA's National Primary Drinkine Water Standard located at: htft>s://www.ei3a.eov/eround-water-and-drinkine-
water/national-Drimarv-drinkine-water-reeulations (accessed 3/27/2023).
b. NHDES AGOS located at: https://www.des.nli.sov/sites/s/files/ehbemt341/files/documents/2020-01/Env-
0r%20600.r)df (accessed 3/27/2023).
c. Based on cis-l,2-DCE, which is lower than trans-l,2-DCE (100 ng/L)
Table K-2: Resit
ential Risk Screening of Soil Cleanup Levels
COC
Soil Cleanup
Level
(mg/kg)
Residential
Soil RSLa (mg/kg)
Cancer Riskb
Noncancer HQC
1 x 106 Risk
HQ = 1.0
FDD A (Area 1)
TCE
0.07
0.94
4.1
7 x 10"8
0.02
Vinyl chloride
0.005
0.059
60
8 x 10"8
0.00008
1.1-DCA
0.36
3.6
16,000
1 x 10"7
0.00002
Toluene
14
--
4,900
--
0.003
Ethylbenzene
17.4
5.8
2,400
3 x 10"6
0.007
1.2-DCE
0.46
--
63d
--
0.007
1.1.1-TCA
2.1
--
8,100
--
0.0003
SBA (Area 2)
TCE
0.004
0.94
4.1
4 x 10"9
0.001
1.2-DCE
0.020
--
63d
--
0.0003
Notes:
-- not applicable; toxicity criteria not established
a. Current EPA RSLs available at: htft>s://www.ei3a.eov/risk/reeional-screenine-levels-rsls-eeneric-tables (accessed
3/27/2023).
b. The cancer risks were calculated using the following equation, based on the fact that RSLs are derived based on
1 x 10"6 risk: cancer risk = (cleanup level cancer-based RSL) x 10~6.
c. The noncancer hazard quotient (HQ) was calculated using the following equation: HQ = cleanup level ^
noncancer-based RSL.
d. RSL for cis-1,2-DCE, which is more stringent than trans-1,2-DCE
K-l
------- |