Fourth Five-year Review Report for Tinkham Garage Superfund Site Town of Londonderry Rockingham County New Hampshire


FOURTH FIVE-YEAR REVIEW REPORT FOR
TINKHAM GARAGE SUPERFUND SITE
TOWN OF LONDONDERRY
ROCKINGHAM COUNTY, NEW HAMPSHIRE

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Prepared by

U.S. Environmental Protection Agency
REGION 1
BOSTON, MASSACHUSETTS

Jdmes T. Owens III, Director
mice of Site Remediation and Restoration

Date

SDMS DocID 563193

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TABLE OF CONTENTS

LIST OF ACRONYMS AND ABBREVIATIONS	 1

EXECUTIVE SUMMARY			.				2

FIVE YEAR REVIEW SUMMARY FORM	3

1.0 INTRODUCTION						5

2.0 PROGRESS SINCE LAST REVIEW										6

3.0 FIVE-YEAR REVIEW PROGRESS			11

4.0 TECHNICAL ASSESSMENT		 15

5.0 ISSUES/ RECOMMENDATIONS					19

6.0 PROTECTIVENESS STATEMENT						19

7.0 NEXT REVIEW	19

APPENDIX A-EXISTING SITE INFORMATION

A.	SITE CHRONOLOGY

B.	BACKGROUND

C.	REMEDIAL ACTIONS

APPENDIX B- MAPS, DATA, FIGURES, AND TABLES

TABLE 4: Water Quality Monitoring Program Requirements
TABLE 5: Detected Volatile Organic Compounds in Surface Water
TABLE 6: Detected Volatile Organic Compounds in Groundwater

FIGURE 1: Site Location Map
FIGURE 2: Site Plan

FIGURE 3: Overburden Groundwater Testing Results,

FIGURE 4: Bedrock Groundwater Testing Results

APPENDIX C- GROUNDWATER STATISTICAL EVALUATION

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LIST OF ACRONYMS AND ABBREVIATIONS

1,2-DCE

Cis-1,2-dichloroethylene

ARAR

Applicable or Relevant and Appropriate Requirement

bgs

Below Ground Surface

CERCLA

Comprehensive Environmental Response, Compensation, and Liability Act

CFR

Code of Federal Regulations

COCs

Contaminants of Concern

COPC

Contaminants of Potential Concern

EPA

United States Environmental Protection Agency

FS

Feasibility Study

FYR

Five-Year Review

GMP

Groundwater Management Permit

GMZ

Groundwater Management Zone

ICs

Institutional Controls

MCLs

Maximum Contaminant Levels

MCLG

Maximum Contaminant Level Goals

MDL

Method Detection Limit

MNA

Monitored Natural Attenuation

NHDES

New Hampshire Department of Environmental Services

NPL

National Priorities List

NCP

National Contingency Plan

NPL

National Priorities List

OHM

Oil and/or Hazardous Material

OU

Operable Unit

O&M

Operation and Maintenance

PPm

Parts per Million

ppb

Parts per Billion

POTW

Publically Owned Treatment Works

PRP

Potentially Responsible Party

PQL

Practical Quantitation Limit

PSD

Performing Settling Defendant

QAPP

Quality Assurance Project Plan

RA

Remedial Action

RAO

Remedial Action Objectives

RAP

Remedial Action Plan

RCRA

Resource Conservation and Recovery Act

RI

Remedial Investigation

ROD

Record of Decision

RPM

Remedial Project Manager

SVOCs

Semivolatile Organic Compounds

TCE

Trichloroethene

VOCs

Volatile Organic Compounds

1

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EXECUTIVE SUMMARY

This is the fourth Five-Year Review (FYR) for the Tinkham Garage Superfund (Site) located in
Londonderry, Rockingham County, New Hampshire (see Figure 1). The purpose of this FYR is
to review information to determine if the remedy is and will continue to be protective of human
health and the environment. The triggering action for this statutory FYR was the signing of the
previous FYR on March 24, 2009. Based upon the past five years of groundwater monitoring
results, the remedy is functioning as intended and conditions at the Site remain protective and do
not warrant a re-evaluation of risk. The remedy at the Tinkham Garage Superfund Site is
protective in the short term because institutional controls are in place to prevent use of and
exposure to contaminated groundwater. Investigations performed since the 2009 Five Year
Review have demonstrated that vapor intrusion is not a concern at the Site and that contaminant
levels in excess of the MCLs and New Hampshire Ambient Groundwater Quality Standards
(AGQS) do not exist outside of the Groundwater Management Zone (GMZ). In order for the
Site to be protective in the long term and document Site closure, the groundwater monitoring
program will be modified to monitor concentration changes in individual fracture zones.

The source control component of the remedy was completed in 1995. Since that time, the groundwater
remedy component has been ongoing. In 2003, an Explanation of Significant Difference (ESD) was
completed by EPA which changed the groundwater remedy to Monitored Natural Attenuation (MNA)
and institutional controls. Since the last five year review, volatile organic compound (VOC)
concentrations in groundwater continue to show an overall decrease. At many of the monitoring wells,
the Maximum Contaminant Levels (MCLs) have been achieved and concentration trends indicate that
MCLs will be achieved in most of the source area monitoring wells within the 15 years predicted in
the 2003 ESD. Concentrations of VOCs exceeding MCLs have not been detected in groundwater from
monitoring wells that define the boundaries of the GMZ. The GMZ is the area established under a
New Hampshire Department of Environmental Services (NHDES) Groundwater Management Permit
which notifies property owners of the groundwater contamination within the GMZ and monitors
groundwater quality (see Figure 2). The Groundwater Management Permit for the Site was renevyed
on December 28, 2012 and will remain in place until groundwater is restored to drinking water
standards.

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Five-Year Review Summary Form

Lead agency: EPA

Click here to enter text.

Author name (Federal or State Project Manager): William Lovely

Author affiliation: Remedial Project Manager, U.S. EPA- Region 1- New England

Review period: 7/25/2013 - 8/30/2014

Date of site inspection: 6/2/2014

Type of review: Statutory
Review number: 4

Triggering action date: 3/24/2009

Due date (fiveyears after triggering action date): 3/24/2014

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Five-Year Review Summary Form (continued)

Issues/ Reco m ni c n d a t io n s

Issues and Recommendations identified in the Five-Year Review:

OU(s): 00

Issue Category: Monitoring

Issue: VOCs and 1,4-dioxane concentrations in excess of MCLs and/or
Ambient Groundwater Quality Standards remaining within individual
fracture zones within the GMZ are not currently monitored.

Recommendation: Modify existing groundwater monitoring program

Affect Current
Protectiveness

Affect Future
Protectiveness

Party
Responsible

Oversight
Party

Milestone Date

No

Yes

PRP

NHDES and
USEPA

June 30, 2015,

Protectiveness Determination
Short-term Protective

Protectiveness Statement:

The remedy at the Tinkham Garage Superfund Site currently protects human health and the
environment because institutional controls are in place to prevent use of and exposure to
contaminated groundwater. Investigations performed since the 2009 Five Year Review have
demonstrated that vapor intrusion is not a concern at the Site and that contaminants in excess of
the MCLs and New Hampshire Ambient Groundwater Quality Standards are within the
Groundwater Management Zone. However, in order for the Site to be protective in the long term
and document Site closure, the groundwater monitoring well network will be modified to enable
the observation of water quality conditions within individual bedrock fracture zones.

iite-wide Protectiveness Statement

Addendum Due Date (if applicable):
Click here to enter a date.

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I. INTRODUCTION

The purpose of a Five-Year Review (FYR) is to evaluate the implementation and performance of a
remedy in order to determine if the remedy will continue to be protective of human health and the
environment. The methods, findings, and conclusions of reviews are documented in five-year review
reports. 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) prepares FYRs pursuant to the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA) Section 121 and the National
Contingency Plan (NCP). CERCLA 121 states:

"If the President selects a remedial action that results in any hazardous substances, pollutants,
or contaminants remaining at the site, the President shall review such remedial action no less
often than each five years after the initiation of such remedial action to assure that human health
and the environment are being protected by the remedial action being implemented. In addition,
if upon such review it is the judgment of the President that action is appropriate at such site in
accordance with section [104] or [106], the President shall take or require such action. The
President shall report to the Congress a list offacilities for which such review is required, the
results of all such reviews, and any actions taken as a result of such reviews. "

EPA interpreted this requirement further in the NCP; 40 Code of Federal Regulations (CFR) Section
300.430(f)(4)(ii), which states:

"If a remedial action is selected that results in hazardous substances, pollutants, or
contaminants remaining at the site above levels that allow for unlimited use and unrestricted
exposure, the lead agency shall review such actions no less often than every five years after the
initiation of the selected remedial action."

EPA conducted a FYR on the remedy implemented at the Tinkham Garage Superfund Site (Site) in
Londonderry, Rockingham County, New Hampshire. EPA is the lead agency for developing and
implementing the remedy for the Site. This review was conducted for the entire Site from
May 2013 through August 2014. This report documents the results of the review. Haley & Aldrich,
under contract as consultants to the Cannons Engineering Sites Group (PRPs), has provided technical
input and summary analysis of the data evaluated for this Five-Year Review Report.

The New Hampshire Department of Environmental Services (NHDES), as the support agency
representing the State of New Hampshire, has reviewed all supporting documentation and provided

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input to EPA during the FYR process.

This is the fourth FYR for the Tinkham Garage Superfund Site. The triggering action for this statutory
review is the previous FYR, which was completed on March 24, 2009. The FYR is required due to the
fact that hazardous substances, pollutants, or contaminants remain at the Site above levels that allow for
unlimited use and unrestricted exposure.

II. PROGRESS SINCE THE LAST REVIEW

Table 1: Protectiveness Determinations/Sta

tements from the 2009 FYR

OU#

Protectiveness
Determination

Protectiveness Statement

Sitewide

Short-term Protective

The remedy at the Tinkham Garage Superfund Site is
expected to be or is protective of human health and the
environment, and in the interim, exposure pathways that
could result in unacceptable risks are being controlled.

Table 2: Status of Recommendations from the 2009 FYR

OU

#

Issue

Recommendations/
Follow-up Actions

Party
Respon
sible

Oversight
Party

Original
Milestone
Date

Current Status

Completion

Date (if
applicable)

00

Increasing
VOC

concentration
trends in
FW11D

Revise and
implement the
monitoring
program with
special attention
toFWllD.

Also, increase
the groundwater
monitoring
frequency to
twice per year
for monitoring
wells NAI-K2,
FW1 ID, and
FW20 and add
nitrate, sulfate,
ferrous iron, total
iron, chloride,
ethane, and
methane to the
analytical testing
parameters to
better evaluate

PRP

EPA/State

5/1/2009

Completed

4/30/2014

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geochemical
conditions.











00

Degradation
rate of some
VOCs slower
than

predicted

Update
groundwater
model to reflect
any changed
cleanup time
predictions.

PRP

EPA/State

11/30/200
9

Considered

But Not
Implemented

4/30/2014

00

The extent
and potential
impact of
1,4-dioxane
is unknown.

Develop and
implement a
workplan to
assess the nature
and extent of
1,4-dioxane
contamination in
groundwater.

PRP

EPA/State

6/30/2009

Completed

12/30/09

00

Based upon

updated risk

based

screening

values,

existing

overburden

data does not

have low

enough

detection

limits to

confirm the

findings of

the 2004 '

vapor

intrusion

screening

analysis.

Collect
overburden
groundwater
data. Develop
and implement a
vapor intrusion
screening
analysis.

PRP

EPA/State

6/30/2009

Completed

12/30/09

. 00

Open
borehole
wells provide
minimum
information

Develop and
implement
workplan to
address
additional data
needs related to
open borehole
well locations.

PRP

EPA/State

6/30/2009

Completed

7/1/14

Recommendation 1: Revise and implement the monitoring program with special attention to FW1 ID.
Also, increase the groundwater monitoring frequency to twice per year for monitoring wells NAI-K2,
FW1 ID, and FW20 and add nitrate, sulfate, ferrous iron, total iron, chloride, ethane, and methane to the

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analytical testing parameters to better evaluate geochemical conditions.

•	The monitoring program was revised beginning in May, 2009. Monitoring wells FW11D, NAI-
K2, and FW20 have been sampled twice per year since May 2009. The additional sampling
rounds improved the assessment that contaminant concentrations in groundwater are either
decreasing or stable (see Section IIIfor further information).

•	VOC concentration trends in FW1 ID have shown a stable to decreasing trend over the past five
years. This is consistent with historical trends and indicates that the increasing concentration
trend noted between 2004 and 2009 has subsequently leveled off.

•	Additional geochemical parameters, including nitrate, sulfate, ferrous iron, total iron, chloride,
ethane, and methane, were tested for two years. The additional geochemical results
demonstrated that biodegradation was continuing to occur and resulting in decreasing VOC
concentrations.

Recommendation 2: Update Groundwater Model to reflect any changed cleanup time predictions.

•	Based upon the observed trends in contaminant concentrations over the last five years and the
presence of 1,4-dioxane, EPA determined that an updated groundwater model was not required
at this time.

Recommendation 3: Develop and implement a work plan to assess the nature and extent of 1. 4-
dioxane contamination in groundwater

•	A work plan was developed and submitted to EPA in August 2009. The work plan focused on
nine private water supply wells along Ross Drive. These are the only private water supply wells
proximate1 to the Tinkham Garage Site and had been sampled numerous times by NHDES for
VOCs historically.

•	Samples of untreated water were collected from the nine private water supply wells in November
2009 and the results were reported in December 2009. Contaminant 1,4-dioxane was not
detected in any of the private water supply wells at a laboratory reporting limit of 0.5
micrograms per liter (ppb), well below the NHDES Ambient Groundwater Quality Standard of 3
ppb.

Recommendation 4: Collect overburden groundwater data, develop and implement a vapor intrusion
screening analysis.

•	A work plan was developed and submitted to EPA in August 2009. The work plan focused on
five shallow overburden monitoring wells. Groundwater samples were collected from each
monitoring well in November 2009 and tested using test methods with lower reporting limits to

1 There are no private water supply wells located downgradient (southwest) of monitoring well FW21D within the GMZ. FW21D
is approximately 450 feet upgradient (northeast) of monitoring well ERT04 and is the most down-gradient monitoring well
with measurable VOC concentrations in excess of the MCLs.

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meet EPA Region I's risk based screening values for assessing vapor intrusion. The results were
reported in December 2009.

• Contaminant concentrations of the 72 target VOCs did not exceed EPA Region I's risk based
screening values in any of the samples. Based upon these sample results and the groundwater
monitoring results dating back to the 1990s, it was concluded that no further assessment of
vapor intrusion was warranted.

Recommendation 5: Develop and implement work plan to address additional data needs related to open
borehole well locations

• A work plan was developed and submitted to EPA January 2014. The work plan focused on
three open borehole monitoring wells that are used to assess the protectiveness of the remedy.
The work plan specified 1.) Borehole geophysics to identify fracture zones in the bedrock; 2.)
hydraulic and chemical testing of discrete fracture zones utilizing packer sampling; and 3.)Data
evaluation to assess the contributions of contaminant mass from the discrete fracture zones.

• A final report of this work has not been completed as of the date of this review, however, the
preliminary conclusions of the bedrock investigation included:

o Overall, the new data supported and affirmed the Conceptual Site Model for the Site:
Releases of VOCs occurred in the source area and migrated downward into the bedrock
in the aquifer recharge area. VOCs then migrated in the dissolved phase in a generally
northeast to southwest direction along the major fracture trend. The findings from the
new data included the following:

¦ The fracture orientations generally show a northeast-to-southwest strike azimuth
and confirm the CSM's preferential northeast-southwest pathway in the fractured
bedrock.

¦ Drawdown was observed above the packers during pumping, indicating the
fractures in the vicinity of the borehole are hydraulically connected. The
interpreted vertical connectivity between fractures is consistent with the
observations of moderately- to steeply-dipping fractures in the geophysics survey.

¦ The interconnection of steep fractures in a northeast-southwest oriented zone
contributes to the horizontal anisotropy identified previously in the Conceptual
Site Model, i.e., the elliptical hydraulic response to pumping that was observed
previously in the Site pumping test.

¦ Estimated hydraulic conductivity values were generally higher in the deeper
zones than the shallow zones indicating that, under pumping and ambient
conditions, the majority of the water will be producedfrom fractures between 70
and 110 feet below ground surface.

¦ The highest concentrations of total VOCs and 1, 4-dioxane were also generally
found in deeper zones in fractures at depths between 70 and 110 feet below
ground surface.

¦ The mass-flux calculations and comparison of water quality in discrete fracture
intervals and open boreholes indicate that the majority of the mass flux in each

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well is associated with deeper fractures that have the highest VOC concentrations
and contribute to the majority of the borehole flow.

Remedy Implementation Activities

The Groundwater Management Permit (GMP) was renewed by NHDES in December 2012. The GMP
specifies the groundwater management zone (GMZ) in which water supply wells are not permitted and
the groundwater monitoring program which documents that contaminant concentrations are decreasing
and not exceeding Ambient Groundwater Quality Standards beyond the boundaries of the GMZ.

Groundwater monitoring in support of the Monitored Natural Attenuation (MNA) remedy was
performed twice per year since the previous five-year review report.

Table 3: Summary of Planned and/or Implemented 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

Each of the
parcel numbers
are identified in
the Groundwater
Management
Permit (No.

GWP-
199004008-L-
003)

Groundwater
use is
restricted
within the
Groundwater
Management
Zone

Deed Restrictions have been placed
on all of the parcels within the GMZ

System Operation/Operation and Maintenance Activities

Since the previous five-year review, operation and maintenance activities have included biannual
groundwater and surface water monitoring as summarized in Table 4 and investigations to assess vapor
intrusion, the extent of 1,4-dioxane in groundwater, and the adequacy of open borehole bedrock
monitoring wells. The results of the vapor intrusion, 1,4-dioxane, and open borehole investigations are
described in reports that are referenced in Section III. (Document Review) of this Five-Year Review.

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III. FIVE-YEAR REVIEW PROCESS

Administrative Components

The PRP was notified of the initiation of the five-year review on 6/3/2013. The Tinkham Garage
Superfund Site Five-Year Review was led by William Lovely of the U.S. EPA, Remedial Project
Manager for the Site and Kenneth Richards, of the NHDES, assisted in the review as the representative
for the support agency .

The review, which began on 7/25/2013, consisted of the following components:

•	Community Notification and Involvement;

•	Document Review;

•	Data Review;

•	Site Inspection; and

•	Interviews.

Community Notification and Involvement

No public meetings are required and, therefore, none were held regarding the Five-Year Review for the
Site. However, EPA did publish a notice regarding the initiation of the Five-Year Review in local
newspapers (e.g., Boston Globe) on 2/13/2014 stating that there was a five-year review and inviting the
public to submit any comments to the U.S. EPA. The results of this review and the report will be made
available at the Site information repositories located at the Leach Public Library, 276 Mammoth Road
Londonderry, NH 03055, and EPA's Superfimd Records Center at 5 Post Office Square, Boston MA
02109.

Document Review

This five-year review consisted of a review of relevant documents including O&M records, monitoring
data, and groundwater cleanup standards. The 2003 Explanation of Significant Differences and the 1989
Amended Record of Decision were also consulted. In addition, the following additional investigation
reports issued since the previous five-year review were reviewed:

•	Summary of Results -1,4-Dioxane in Private Water Supply Wells on Ross Drive Tinkham's
Garage Superfund Site Londonderry, New Hampshire dated December 30, 2009

•	Summary of Results - Vapor Intrusion Screening Tinkham's Garage Superfund Site
Londonderry, New Hampshire dated December 30, 2009

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• Draft, Fractured Bedrock Evaluation Tinkham Garage Site Londonderry, New Hampshire dated
July 1, 20142

Each of these documents has been made part of the Site file and are available for viewing by the public.
Data Review

The review of records and monitoring reports covering the past five years of groundwater monitoring
indicates that the remedy is performing as intended, the VOC plumes are not expanding, and natural
attenuation is occurring in accordance with the ROD. In addition, surface water data collected as part of
the water quality monitoring program did not show unacceptable risks from groundwater discharges.
Table 6 presents the groundwater monitoring results from May 2009 through April 2014. Figures 3 and
4 depict groundwater flow direction and concentrations for both overburden and bedrock groundwater.
Additional discussion regarding the monitoring results is presented in the 2009-13 Annual Water
Quality Monitoring Reports, which are included as part of the Site file.

Since the 2009 FYR, three investigations have been completed in response to recommendations. These
investigations include the following:

>	Vapor Intrusion Assessment - In 2009, groundwater samples were collected to assess whether
VOC concentrations in overburden groundwater were elevated such that vapor intrusion could
represent a potential exposure pathway. Consistent with the historical groundwater monitoring
dating back to the 1990s, VOC concentrations in overburden groundwater were below EPA
Region I's risk based screening values for.assessing vapor intrusion and, therefore, no further
assessment is required for vapor intrusion.

>	Extent of 1,4-dioxane Assessment - In 2009, samples of private water supply wells at homes on
Ross Drive were collected and tested for 1,4-dioxane. No 1,4-dioxane was detected in any of the
private water supply wells. These private water supply wells are outside of the groundwater
management zone (GMZ), generally cross-gradient to observed groundwater flow, had
historically been tested for VOCs by NHDES and were always found to have no detectable VOC
concentrations attributable to the Site.

2 This document is currently being revised in response to comments that EPA made in a letter dated August 6,2014. The document
will be included as part of the Site file when it is finalized.

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> Open Bedrock Borehole Investigation - An investigation of three out of seven bedrock open
borehole monitoring wells was implemented to assess the protectiveness of the remedy and
whether the open borehole monitoring results were adequately representing groundwater quality
conditions at the Site. The results of the investigation affirmed the Conceptual Site Model for
the Site and that the remedy is protective. However, EPA, in consultation with NHDES, has
concluded that the presence of elevated contaminant concentrations within discrete fractures
suggests that modifications to the existing groundwater monitoring program are needed for the
purpose of better tracking groundwater trends and the contaminant plume over time.

Based on the results of the biannual groundwater monitoring, concentrations of VOCs generally
continue to decrease in the overburden and bedrock groundwater. VOC concentrations are approaching
or have achieved the NHDES Ambient Groundwater Quality Standards and federal MCLs in all but four
of the monitoring wells (NAI-K2, FW1 ID, DVE7, and FW20) in the current groundwater monitoring
program. The contaminant 1,4-dioxane, which was first tested for in 20083, has shown downward
concentration trends in the overburden groundwater and stable to downward concentration trends in the
bedrock groundwater.

Groundwater concentrations of VOCs and 1,4-dioxane remain below NHDES Ambient Groundwater
Quality Standards and federal MCLs in the boundary wells (FW25, FW28D, and ERT04) used to
monitor protectiveness at the east-southeast and southern edge of the GMZ.

Volatile Organic Compound Concentration Trends in Groundwater

VOC concentrations in overburden and bedrock groundwater continue to decrease. In April 2014, only
one overburden monitoring well had total VOCs in excess of 100 ppb (FW20 at 104 ppb) versus three
overburden monitoring wells in 2008 (NAI-M1, OW2D, and FW20). Similarly, total VOC
concentrations decreased in bedrock monitoring wells over the past five years. In April 2014, only one
bedrock monitoring well had total VOCs in excess of 100 ppb (NAI-K2 at 324 ppb) versus three
bedrock monitoring wells in 2008 (FW1 ID, FW21D, and NAI-K2).

In addition, VOC data generated over the past five years of monitoring demonstrate that concentrations
of individual VOCs are generally continuing to decrease Site-wide. A direct comparison of
concentrations of individual VOCs greater than MCLs in May 2008 with March 2014 concentrations

3 NHDES Waste Management Division established state-wide sampling and analytical requirements for 1,4-dioxane.

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indicates that 75% of the individual VOC concentrations Site-wide decreased over this period. The
remaining concentrations were unchanged at or approaching the MCLs.

The decreasing concentration trends of each of the individual VOC greater than MCLs were confirmed
using the Mann Kendall (M-K) test. As shown in Appendix B, all but one VOC in excess of MCLs or
NHDES Ambient Groundwater Quality Standards in one monitoring well (vinyl chloride in NAI-K2)
have negative M-K Statistic (S) values. S values provide an indication of a decreasing trend (negative S
values) or an upward trend (positive S values). The magnitude of S indicates the strength of the trend
(either decreasing or increasing).

As reported in the 2009 FYR, for the groundwater monitoring period of 2003 through 2008, the VOC
concentrations at FW1 ID showed an increasing trend despite the fact that no new releases of VOCs
were known to have occurred at the Site. This trend has reversed during the 2008 to 2014 monitoring
period. A decreasing/stable trend and negative M-K S values were observed for all of the individual
VOCs detected above MCLs at FW1 ID. It remains unknown as to why an increasing trend occurred
between 2003 and 2008.

1.4-Dioxane Concentration Trends in Groundwater

In January 2008, NHDES established sampling and analytical requirements for 1,4-dioxane, including
the establishment of a 3.0 ug/1 reporting limit (equal to the current AGQS for the compound). In August
2010, the US Environmental Protection Agency, under the Integrated Risk Information System (IRIS),
published a drinking water cancer risk value for 1,4-dioxane for a 1 in one million risk of 0.35 |xg/L.

This new cancer risk value was established after a comprehensive review of toxicity data by EPA health
scientists from several program offices, regional offices and the Office of Research and Development.
In response and in order to obtain a better understanding of the possible extent of 1,4-dioxane
contamination in groundwater, NHDES required that starting in November, 2011, all analyses for 1,4-
dioxane utilize an analytical method which will have a reporting limit of 0.25 |xg/L. This requirement
can be waived at sites where 1,4-dioxane is demonstrated to be absent.

Since 2008, concentrations of 1,4-dioxane greater than the AGQS have been measured in the source area
and down-gradient areas but not at the boundaries of the GMZ. Concentration trends for 1,4-dioxane
show negative S values from the M-K Test for all of the monitoring wells with 1,4-dioxane trends
measured greater than 3 ppb with the exception of FW1 ID. At well FW1 ID, 1,4-dioxane has been

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detected at 110 to 500 ppb during 2009-2014 sampling. No trend was observed for 1,4-dioxane
concentrations in groundwater from 2008 through April 2014. Further evaluation of the trend will be
made as part of the 2019 Five Year Review when more data is available.

Site Inspection

The inspection of the Site was conducted on 6/2/2014. In attendance were William Lovely, U.S. EPA;
Kenneth Richards of the NHDES, and Mr. Ian Phillips of Haley & Aldrich. The purpose of the
inspection was to assess the protectiveness of the remedy. During the Site inspection, the condition of
the monitoring wells was inspected and areas of the additional bedrock investigation were observed. No
issues were noted during the inspection.

Interviews

During the FYR process, interviews were conducted with parties impacted by the Site, including the
current landowners, and regulatory agencies involved in Site activities or aware of the Site. The purpose
of the interviews was to document any perceived problems or successes with the remedy that has been
implemented to date. Interviews were conducted informally between January and June 2014 during
regularly scheduled Site visits related to the annual groundwater sampling event and bedrock
investigation. No issues were noted during these informal discussions.

IV. TECHNICAL ASSESSMENT

Question A: Is the remedy functioning as intended by the decision documents?

Yes. Since the last five year review, VOC concentrations in groundwater have shown a general overall
decrease. At many of the monitoring wells, the MCLs have been achieved and concentration trends
indicate that concentrations are continuing to decrease and approach MCLs. Monitoring wells with
concentrations of 1,4-dioxane greater than NHDES Ambient Groundwater Quality Standards in 2008
(FW1 ID, FW20, FW21D, OW2D, and LGSW) continue to exceed Ambient Groundwater Quality
Standards in 2014. However, M-K S values are negative for 1,4-dioxane in each of these monitoring
wells with the exception of FW1 ID. Monitoring wells that establish the boundaries of the Site and the
GMZ (FW28D, ERT04, and FW25) continue to have no detectable concentrations of VOCs and 1,4-
dioxane in excess of MCLs or AGQS values. The PRPs utilize these wells to demonstrate compliance
with the GMP.

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The institutional controls to prevent the ingestion of contaminated groundwater remain in effect through
the December 28, 2017 GMP approved by NHDES. In addition, as required by the prospective
purchaser agreement with Gilcreast Realty Holdings II, LLC, as assigned to the Nevins Retirement
Cooperative Association, property deeds prohibit the use of groundwater for drinking water purposes.
Properties owners located within the Groundwater Management Zone (GMZ) do not use groundwater as
a potable source as their homes are all connected to the Town's municipal water supply. Consequently,
no one is currently known to be consuming contaminated groundwater. Furthermore, additional testing
for 1,4-dioxane was performed at the private water supply wells along Ross Drive (south-southeast of
the source area) and no 1,4-dioxane was detected at the reporting limit of 0.5 ng/L. A municipal records
review in 2009 indicated that there are no private water supply wells to the west for at least 1,000 feet
beyond the GMZ.

Question B: Are the exposure assumptions, toxicity data, cleanup levels, and remedial action
objectives (RAOs) used at the time of the remedy section still valid?

No. Some of the exposure assumptions, toxicity data, and/or cleanup levels in place at the time of the
original remedy selection are no longer valid although the RAOs remain valid. Some toxicity factors for
contaminants of concern as identified in the ROD and past FYRs have changed since 2009. In
particular, on September 28, 2011, EPA finalized the revised toxicity assessment for trichloroethene
(TCE) with new toxicity values. Based on the new assessment, TCE is more toxic for both cancer and
non-cancer health effects. In November 2010 and September 2013, EPA finalized the cancer and non-
cancer toxicity assessment for 1,4-dioxane, showing 1,4-dioxane to be more toxic for both cancer and
non-cancer effects. These particular changes to the toxicity values of TCE and 1,4-dioxane would result
in an increase of estimated Site risks should groundwater be consumed/used for potable purposes.. On
February 10, 2012, EPA also finalized the revised toxicity assessment for tetrachloroethene (PCE).

Based on the new assessment, PCE is more toxic for cancer effects but less toxic for non-cancer health
effects, resulting in an increase in estimated cancer risk but a decrease in estimated non-cancer hazard.
On September 30, 2010, EPA finalized the non-cancer toxicity assessment for cis-l,2-dichloroethene
(cis-l,2-DCE), increasing its non-cancer hazard. Overall, if exposed to contaminated groundwater,
cancer risks are estimated to increase and non-cancer hazard might increase or decrease, depending of
the levels of PCE and cis-l,2-DCE.

Toxicity factors which have changed since the last Five Year Review are presented in the table below.

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Summary of Updated Toxicity Factor Changes since 2009

Substance

Potential
Exposure
Medium

Date/Source

RfDorai
(mg/kg-
day)

RfC
(Hg/m3)

CSForai
(mg/kg-
day)1

Unit Risk
(Hg/m3) 1

Cis-1,2-
Dichloroethene

Groundwater

9/30/1 o/iws

2.0E-03

NA

NA .

NA

1,4-Dioxane

Groundwater

8/11/10
9/20/13/
IRIS

3.0E-02

3.0E+01

1.0E-01

5.0E-06

Tetrachloroethene

Groundwater

2/10/12/IRIS

6.0E-03

4.0E+01

2.0E-03

3.0E-07

Trichloroethene

Groundwater

9/28/11/IRIS

5.0E-04

2.0E+00

5.0E-02

4.0E-06

Notes:

RfDorai - Reference Dose for chronic exposure used to estimate non-cancer adverse health effects resulting from oral exposure.
RfC - Reference Concentration for chronic inhalation exposure used to estimate non-cancer adverse health effects
resulting from inhalation exposure.

CSForai - Cancer Slope Factor used to estimate cancer health effects resulting from oral exposure.

Unit Risk - Inhalation Unit Risk used to estimate cancer health effects resulting from inhalation exposure.

IRIS - Integrated Risk Information System
NA - Not Available

In 2014, EPA finalized a Directive to update standard default exposure factors and frequently asked
questions associated with these updates:

http://www.epa.gov/oswer/riskassessment/siiperfund hh exposure.htm

(items # 22 and #23 of this web link). Many of these exposure factors differ from those used in the risk
assessment for the 1986 ROD. These changes in general would result in a slight decrease of the risk
estimates for exposure to most chemicals at the Site. Although calculated risks from potential exposure
pathways at the Site may differ from those previously estimated, higher for some contaminants and
lower for a few others, the revised methodologies themselves are not expected to affect the
protectiveness of the remedy.

Due to the updated changes in toxicity values and standard default exposure factors since 2009, the
estimated Site risks would change. However, the remedy is still considered protective since the selected
groundwater cleanup levels are MCLs, which have not changed since the ROD, and there is currently no
use of groundwater for any purposes.

In 2008, 1,4-dioxane was detected in groundwater at the Site greater than the NHDES Ambient

Groundwater Quality Standards of 3 ng/1 and was further assessed relative to potential exposures to

private water supply wells in the vicinity of the Site. Additional testing for 1,4-dioxane was performed at

17

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the private water supply wells along Ross Drive (south-southeast of the source area) and no 1,4-dioxane
was detected at the reporting limit of 0.5 ng/L. This reporting limit is below NHDES AGQS. Ross
Drive is also not part of the Site and is not part of the Groundwater Management Zone.

The potential for risk associated with indoor air exposure pathways (vapor intrusion) was assessed
following the 2004 and 2009 FYRs and determined not to be a concern at the Site. This conclusion was
affirmed with a comparison of the 2002 vapor intrusion (VI) groundwater screening levels to the current
(2014) VI screening levels for contaminants that continue to be detected in groundwater. Although the
screening levels for some contaminants has changed, the conclusions presented in the 2009 VI screening
remain valid given that the 2009 data are also below the current VI screening levels, even in cases where
the levels were revised to be more stringent. Furthermore, passive VI systems were installed during
construction of The Nevins senior housing complex to prevent possible future indoor air exposures at
locations directly downgradient of the source area.

Question C: Has any other information come to light that could call into question the protectiveness of
the remedy?

Yes. The levels of VOCs and 1,4-dioxane concentrations present within individual fracture zones in
excess of MCLs and/or NHDES Ambient Groundwater Quality Standards will need to be reduced in
order for long term protectiveness to be achieved. The existing GMZ notifies property owners of the
groundwater contamination within the GMZ boundaries and, therefore, helps to prevent current and
future exposures until MCLs and/or NHDES Ambient Groundwater Quality Standards are achieved.

Technical Assessment Summary

Site data and reports reviewed since the 2009 five year review show that the groundwater remedy
continues to function as intended by the 1986 ROD, as modified by the 2003 ESD. Although some
monitoring wells continue to show levels in excess of MCLs and/ or NHDES Ambient Groundwater
Quality Standards, the overall trend of groundwater contaminant levels generally continues to decline,
with the possible exception of 1,4-dioxane in monitoring well FW1 ID which shows no trend at this
time. Continued groundwater monitoring with a modified program based on new information from the
Bedrock Evaluation Report (draft) will allow EPA, NHDES, the PRPs, and other stakeholders to better
track the performance of the MNA remedy described in the 2003 ESD, while institutional controls
continue to prevent current and future exposures to groundwater contaminants in excess of MCLs and/or
NHDES Ambient Groundwater Quality Standards.

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V. ISSUES/RECOMMENDATIONS AND FOLLOW-UP ACTIONS

Table 5: Issues and Recommendations/Follow-up Actions

ou#

Issue

Recommendations/
Follow-up Actions

Party
Responsible

Oversight
Agency

Milestone
Date

Affects Proteetiveness?
(Y/N)

Current

Future

VOCs and 1,4-dioxane
concentrations in
excess of MCLs and/or
Ambient Groundwater
Quality Standards
remaining within
individual fracture
zones within the GMZ
are not currently
monitored.

Modify existing
groundwater
monitoring program

PRPs

NHDES
and USEPA

6/30/2015

Yes

VI. PROTECTIVENESS STATEMENT

Sitewide Proteetiveness Statement

Proteetiveness Determination: Addendum Due Date (if applicable):

Short-term Protective Click here to enter a date.

Proteetiveness Statement:

The remedy at the Tinkham Garage Superfund Site currently protects human health and the environment
because institutional controls remain in place to prevent use of and exposure to contaminated groundwater.
Investigations performed since the 2009 Five Year Review have demonstrated that vapor intrusion is not a
concern at the Site and that contaminants in excess of the MCLs and New Hampshire Ambient
Groundwater Quality Standards are within the Groundwater Management Zone. However, in order for the
Site to be protective in the long term and document Site closure, the groundwater monitoring progriam will
be modified to enable the observation of water quality conditions within individual fracture zones.

VII. NEXT REVIEW

The next five-year review report for the Tinkham Garage Superfund Site is required five years from the
signature date of this review.

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APPENDIX A - EXISTING SITE INFORMATION
A. SITE CHRONOLOGY

Table 7: Site Chronology			

Event

Date

Initial discovery of problem or contamination

April 1978

Condominium and individual residential wells shut down

January 1983

Final NPL listing

September 8,1983

Water line installed

November 1983

Remedial Investigation/Feasibility Study complete

September 30, 1986

ROD signature

September 30, 1986

Administrative Order on Consent requiring PRPs to perform
pre-design studies to assess source control remedial
technologies

September 11, 1987

Pre-design study complete

July, 1988

Amended ROD changing source control remedial

March 10, 1989

technologies



Consent Decree requiring PRPs to implement amended ROD
remedy

August 14, 1989

ESD addressing on-site groundwater treatment

January 21, 1992

Sewer line construction starts

March 1993

On-site remedial action construction start

April 7, 1994

Start of source control and groundwater treatment plant

November 28, 1994

operation



RA Construction completion (Preliminary Close-out Report)

April 7, 1995

Vacuum extraction system dismantled

November 1995

Bedrock extraction wells shut down

July, 1996

First five-year review report

March 31, 1999

NHDES issues Groundwater Management Zone (GMZ)
Permit

October 30,2002

All extraction wells shut down

November 2002

ESD documenting groundwater remedy change to natural

March 31, 2003

attenuation



Second five-year review report

March 2004

NHDES issues renewal of the GMZ permit

November 27, 2007

Third five-year review report

March 24, 2009

Vapor Intrusion Investigation Report

December 30, 2009

1.4-Dioxane Investigation on Ross Drive Report

December 30, 2009

NHDES issues renewal of the GMZ permit

August 28, 2012

Bedrock Evaluation Report (draft)

July 1,2014

EPA letter responding to Bedrock Evaluation Report (draft)

August 6, 2014

20

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B. BACKGROUND

Physical Characteristics

The Tinkham Garage Superfund site (the Site) situated in Londonderry, New Hampshire, is
approximately one mile southwest of the intersection of interstate Route 93 and state Route 102. It is
bounded by state Route 102 to the north, Gilereast Road to the east, Ross Drive to the south and the
Woodland Village Condominium complex to the west. The Site includes various developed areas.
Undeveloped land features include wooded areas, open fields and wetlands.

The topography of the Site is relatively flat with surface drainage from north to south. An unnamed
tributary and an attached intermittent stream branch through the condominium complex and discharge
off-Site to Beaver Brook south of Ross Drive. In turn, Beaver Brook discharges to the Merrimack River
farther to the south. The 100 year flood plain on the Site extends from Route 102 and follows the
unnamed tributary along to its confluence with Beaver Brook. The floodplain is generally 100 feet wide
along its path through the condominium complex. This area forms an approximately two acre wetland.
Beyond the Site boundaries, south of the condominium complex, and before the tributary's confluence
with Beaver Brook, the flood plain widens considerably forming a sixty-six acre wetland. In addition,
there is a fifty-seven acre wetland at the southeast corner of the Site.

Land and Resource Use

The Site encompasses 375 acres of residential, commercial and undeveloped land. In addition to the
Woodland Village Condominium complex, there are single family homes along Mercury and McAllister
Drives in the northern portion of the Site, and along Gilereast Road and Ross Drive bordering the
southern boundary of the Site. The Tinkham Realty office and Tinkham Garage are located in the
northeastern portion of the Site. In 2003, Home Depot, Staples, 99 Restaurant, and Dunkin' Donuts
completed construction of a retail facility on the northeastern portion of the Site.

In January 2003, Gilereast Realty Holdings II, LLC purchased the 95-acre area in the central portion of
the Site for development into active senior housing called The Nevins. The Nevins Retirement
Cooperative Association owns the land upon which individually owned residential structures have been
constructed. As of November 27, 2007, approximately 126 homes have been completed and 30 homes
were individually owned and presumed to be occupied. The developer has a proposed purchaser
agreement with EPA. Per agreements with EPA, these homes were originally constructed without

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basements and had subslab depressurization systems (SSDS) installed. EPA allowed the developer to
include basements in future homes beginning in approximately 2005.

Prior to the installation of a permanent waterline, the primary source of drinking water to the area was
the bedrock aquifer. The groundwater flow in bedrock appears to take place largely in fracture zones
which have a northeast/southwest orientation. Groundwater in bedrock discharges to the unnamed
tributary on site from both east and west of the tributary. Additionally, there exist several artesian
bedrock wells along Mercury Drive and within the condominium complex. Groundwater discharging to
the surface from these wells migrates to the unnamed tributary via surface flow.

History of Contamination

It is believed that waste disposal took place at the Tinkham Garage during 1978 and 1979. In April of
1978, complaints of foam and odors occurring in a small unnamed brook which crosses Ross Drive led
representatives of the Londonderry Health Department to investigate the Site. Their investigation
concluded that liquids and sludge from tank truck washings had been dumped behind Tinkham Garage
directly to the ground surface. A subsequent citizen complaint to the New Hampshire Water Supply and
Pollution Control Commission (NHWSPCC, now New Hampshire Department of Environmental
Protection (NHDES)) resulted in an order to remove surface contamination. Additionally, a trench was
excavated to divert surface run-off from behind the garage area away from Ross Drive.

Initial Response

In January of 1983, the drinking water supply well servicing Londonderry Green Apartments (currently
Woodland Village Condominiums) and residential wells along Mercury and McAllister Drives were
taken out of service because of documented or potential organic contamination. The EPA temporarily
supplied water until a permanent water line was installed by NHWSPCC under cooperative agreement
between the state and the EPA in November of 1983.

Basis for Taking Action

The conclusions of the remedial investigation of the Site, as described in the ROD, indicate that VOCs
were the predominant contaminants of concern and presented the major risk to public health and welfare
and the environment.

VOCs were detected in soil in four areas within the Site and in both the overburden and bedrock

¦22

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groundwater aquifers. In the overburden, the VOCs in groundwater were found to be migrating in a
south-southwesterly direction and discharging to the surface water of the unnamed tributary and the
wetlands area to the south of Tinkham Garage. In addition, slight downward gradients resulted in VOCs
entering the bedrock aquifer. Once in the bedrock aquifer, migration of VOCs was found to be
primarily controlled by the alignment of the water bearing fracture sets which are oriented in a northeast
to southwest direction based upon two pump tests. The alignment of the fracture sets indicated that it
was unlikely that VOCs in the bedrock aquifer would reach the private water supply wells located along
Ross Drive to the South of the Site. The absence of Site-related VOC contamination along Ross Drive
was confirmed by monitoring performed by NHDES until 2006.

VOCs were also detected in surface water and corresponding sediment samples in areas of groundwater
discharge including the unnamed tributary and the attached intermittent stream which flow through the
condominium complex, and the wetland areas to the south of Tinkham Garage.

A risk assessment was completed as part of the remedial investigation. The risk assessment identified
that VOCs in groundwater posed the greatest potential for risk at the Site. The risk posed by soil was
predominantly limited to the potential for VOCs in soil to continue to contribute to contamination of the
groundwater. Contaminants that were detected in onsite surface waters and associated sediments were
concluded not to pose a significant risk to public health and welfare and the environment.

C. REMEDIAL ACTIONS
Remedy Selection

The remedial action objectives were presented in the Record of Decision (ROD), issued September 30,
1986, for source control and management of migration response alternatives and were developed to
mitigate existing and future potential threats to public health and the environment.

The remedial action objectives for source control are:

>	Mitigating further release of contaminants to the surrounding environmental media; and

>	Eliminating or minimizing the threat posed to public health, welfare and the environment from
the source area.

The remedial objectives for management of migration are:

>	Mitigating further migration of contaminants beyond their current extent; and

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>	Eliminating or minimizing the threat posed to public health, welfare and the environment from
the current extent of contaminant migration.

To meet these objectives, the ROD included the following components:

>	Excavation of contaminated soils with onsite treatment;

>	Removal of contaminated groundwater from the overburden and bedrock aquifers with off-site
treatment at the Derry wastewater treatment facility which may be preceded by on-site
pretreatment, with monitoring; and

>	Development of legislation by the Town of Londonderry, New Hampshire and/or the State of
New Hampshire which prevents the present and future use of the on-site aquifer.

Based on conclusions presented in the July 1988 Pre-Design Study Report, EPA issued an Amended
ROD for the Site on March 10,1989, which changed the source control remedial technology to vacuum
extraction. This amendment further specified the management of migration remedy to extract
contaminated deep groundwater from two of the Woodland Village Condominium wells, LGAW and
LGSW, as well as the contaminated shallow groundwater from the vacuum extraction process. The
contaminated shallow groundwater pumped during the vacuum extraction remediation was to be treated
on-site before being mixed with the water from the condominium wells and conveyed via a sewer to the
Derry wastewater treatment facility.

Problems arose concerning funding of the sewer, so EPA issued an Explanation of Significant
Difference (ESD) on January 21, 1992, which allowed for the on-site treatment of all contaminated
groundwater. Before that remedial component could be implemented, however, the sewer was funded
and completed allowing the amended ROD remedy to be accomplished. This was documented in a
second ESD issued on March 31, 2003, which retracted the first ESD. In addition, the 2003 ESD
determined that, after several years of active groundwater extraction and treatment, natural attenuation
could achieve the objectives of the management of migration remedy. Furthermore, the 2003 ESD
established that the use of a New Hampshire Groundwater Management Permit satisfied the institutional
control requirements of the ROD to prevent present and future use of the on-site aquifer.

Remedy Implementation

Following issuance of the 1986 ROD, EPA negotiated an agreement in September 1987 to have the
PRPs conduct a Pre-Design study. The results of this study were presented in the Pre-Design Study
Report issued in July 1988. Based on conclusions presented in the July 1988 Pre-Design Study Report,
EPA issued an Amended ROD for the Site in March of 1989.

24

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A second Consent Decree which, in part, required the PRPs to implement the remedial action, was
entered by the District Court and became effective on September 14, 1989. Following entry of the
Decree, the PRPs began the remedial design and planning for remedial action.

Implementation of the remedy required off-site treatment of extracted groundwater at the Derry
wastewater treatment facility. Conveyance of extracted groundwater to the Derry wastewater treatment
facility required Construction of a new sewer line between the Site in Londonderry and the wastewater
treatment facility located just over the town line in Derry (a total distance of about one mile).
Responsibility for construction of the sewer line was assigned to the Site owner under the Consent
Decree. The Site owner partnered with a local developer who planned to construct the sewer line as part
of a public/private construction project planned by Londonderry. As a municipal project, the sewer line
was designed with a capacity to serve existing and planned residential and commercial needs, in addition
to the extracted groundwater from the Site. Construction of the sewer line began in March of 1993.

The vacuum extraction system was designed and constructed and began operation in November of 1994.
In addition to soils treatment, groundwater extraction from both the shallow and bedrock aquifers was
also initiated. Bedrock groundwater was extracted from two former supply wells, LGAW and LGSW,
and was conveyed back on-Site via a dedicated sewer line. Shallow groundwater was extracted through
the vacuum extraction wells and was pretreated on-site. The bedrock and shallow groundwater was then
mixed and the combined flow was discharged to the Derry wastewater treatment facility through the
newly constructed municipal sewer.

Analytical results confirmed that the vacuum extraction system achieved the soil remediation goal of
total VOCs less than 1 mg/kg in September of 1995. In November of 1995, the vacuum extraction
system was dismantled and the shallow groundwater extraction system was modified to operate
independently via six shallow extraction wells. Pre-treatment was also discontinued at this time since
contamination levels in the extracted groundwater were less than the influent limits imposed by the
wastewater treatment facility.

A temporary shutdown of the two bedrock groundwater extraction wells was granted in July of 1996
since sampling indicated that contaminants had achieved steady-state conditions in LGSW, LGAW and
other bedrock monitoring wells located throughout the Site. Monthly monitoring of VOC levels in wells
LGSW and LGAW was performed from July 1996 through February 2001. VOC levels in both wells,
and other bedrock monitoring wells throughout the Site, remained statistically constant, further

-------
supporting the conclusion that a steady-state condition was present in the bedrock. Furthermore,
sampling results documented evidence of natural attenuation and assessment of the data indicated that
natural attenuation would attain groundwater remediation goals in the shallow aquifer within a 15 year
period.

In May 1997, two years after initiation of active groundwater extraction and consistent with the
Amended ROD, the PRPs requested EPA evaluate the permanent shutdown of the complete
groundwater extraction system based on evidence of natural attenuation in the shallow aquifer and
attainment of steady-state conditions in the bedrock aquifer.

In the Quarter 9 monitoring report (dated July 31, 1996), the PRPs reported substantial evidence of
natural attenuation through intrinsic bioremediation in the shallow aquifer. More specifically:

a.	high dissolved oxygen levels were recorded in areas with reduced VOC levels;

b.	electron receptors including ferric iron and sulfate were present;

c.	the range of pH levels were favorable for microbial growth;

d.	elevated levels of dissolved hydrocarbon gases indicated dechlorination reactions were
occurring;

e.	significantly high microbial plate counts were consistently found throughout the plume area; and

f.	a two dimensional groundwater flow and transport model predicted that MCLs would be attained
throughout the shallow plume within a 15 year period.

In March 2003, EPA issued an ESD to the 1986 ROD, the 1989 Amended ROD, and the 1992 ESD for
the Tinkham Garage Site. Specifically, the 2003 ESD documented the following changes:

>	Modification of the groundwater remedy from active extraction to natural attenuation;

>	Clarification of the type of institutional controls necessary for the groundwater remedy; and

>	Retraction of the 1992 ESD to reflect the actual approach for the discharge of treated
groundwater used at the Site.	'

Based upon a review of the monitoring data and the supporting documentation provided by the PRPs,
EPA and NHDES agreed with the recommendation that the active groundwater extraction system be
discontinued. This decision was based on the following considerations outlined in the March 2003 ESD:

1.	Steady-state conditions exist in the condominium area bedrock aquifer;

2.	Active natural attenuation of the remaining VOC contamination is occurring in the former source
area;

3.	Further migration of VOC plumes in the shallow or bedrock aquifer beyond their current extent
is highly unlikely;

26

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4. Natural attenuation of contaminants in the shallow aquifer will attain the clean-up objectives
established in the 1986 ROD; and

5. Institutional controls have been established and will remain until such time as groundwater is
restored to a condition that allows for unrestricted use.

Currently, groundwater monitoring is performed to demonstrate that the VOC plumes are not expanding
and that natural attenuation is occurring in accordance with the Groundwater Management Permit issued
by NHDES. If these monitoring results demonstrate migration of the shallow or bedrock plume beyond
its current extent, or indicate active natural attenuation is no longer present or no longer adequate to
achieve remedial goals, EPA, in consultation with NHDES, may modify this decision and require active
extraction or other reasonable actions to attain the required remedial goals.

Institutional controls to prevent the ingestion of contaminated groundwater remain necessary until such
time as groundwater is restored to drinking water standards. Currently, no one is known to be consuming
the contaminated groundwater. Public water was extended to all impacted residents in 1983.4 These
residents continue to have public water available as their primary drinking water source. On October 30,
2002, NHDES issued Groundwater Management Zone permit number GWP-199004008-L-001 to the
PRPs. Properties owners located within the Groundwater Management Zone (GMZ) are tied into the
municipal water supply and do not use groundwater. There is no one known to be consuming the
contaminated groundwater and having this groundwater for any domestic uses such as showering,
bathing, dish washing, or laundry. This permit was renewed on December 28, 2012. The permit
requires that groundwater monitoring of key monitoring wells and two surface water sampling locations
are sampled on a combination of semi-annual and annual basis.

System Operation/Operation and Maintenance

Operation of the monitored natural attenuation remedy includes sampling of monitoring wells. Periodic
maintenance and inspection of monitoring of wells is performed by the PRPs contractor. The PRPs
contactor also inspects wells to ensure that they are locked and secured. There have been no major
operation and maintenance issues. Contractor costs to sample and maintain wells range from $15,000 to
$25,000 per year.

4 Impacted residents were located on Mercury Drive and McAllister Drive and at the Woodland Village Condominium Complex
located west of the former source area.

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APPENDIX B — additional maps, data, figures, or tables for reference

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Table 4

Water Quality Monitoring Program

Tinkham Garage Site, Londonderry, New Hampshire

Semi-Annual Monitoring Locations • Sampled in May and November

Location

Monitoring Objective

Location Description

Screened Interval

Diameter
(inches)

Sampling Point
(ft below ground)

Sampling Procedure

Sampling Parameters

SW1

Downgradient plume monitoring

Surface water near OW2D, marked with green metal
stake

surface

Grab

Field parameters. VOCs, 1,4-dioxane

SW2

Downgradient plume monitoring

Surface water near OW2D, marked with green metal
stake

surface

Grab

Field parameters, VOCs, 1,4-dioxane

OW2D

Downgradient plume monitoring

In woods east of the Nevins Active Senior
Community, marked with flagging

14-19

Low Flow-

Field parameters, VOCs, 1,4-dioxane, MNA

FW11D

Downgradient plume monitoring

In backyard area of houses on Harriet Court in the
Nevins Active Senior Community

42-98

5.5

Pump 3 Well Volumes /
Wattera

Field parameters, VOCs, 1.4-dioxane, MNA

FW20

Downgradient plume monitoring

In woods east of the the Nevins Active Senior
Community, marked with flagging

8-48

1.5

Pump 3 Well Volumes /
Wattera

Field parameters, VOCs, 1,4-dioxane, MNA

FW28D

GMZ boundary monitoring

Near stone wall by the Nevins Active Senior
Community

Open hole in rock 77-
205

Pump 3 Well Volumes /
Grundfos

Field parameters, VOCs, 1,4-dioxane, MNA

NAI-K2

Source area monitoring

Southwest comer of Home Depot lot, adjacent to
traffic island

17.7-22,7

Low Flow-

Field parameters, VOCs, 1,4-dioxane, MNA

ERT04

GMZ boundary monitoring

In condo complex

Open hole in rock 20-60

Pump 3 Well Volumes /
Grundfos

Field parameters, VOCs, 1,4-dioxane, MNA

Annual Monitoring Locations

- Sampled in May

Location

Monitoring Objective

Location Description

Screened Interval

Diameter
(inches)

Sampling Point
(ft below ground)

Sampling Procedure

Sampling Parameters

NAI-M1

Source area monitoring

Base of hill behind Home Depot, southwest comer of
parking lot

3-13

Low Flow-

Field parameters, VOCs. 1,4-dioxane, MNA

DVE-7

Source area monitoring

Southwest comer of Home Depot lot, adjacent to
guard rail

16-34

Pump 3 Well Volumes /
Grundfos

Field parameters, VOCs. 1,4-dioxane, MNA

DVE-3

Source area monitoring

Base of hill behind Home Depot, southwest comer of
parking lot

2-22

Pump 3 .Well Volumes /
Grundfos

Field parameters. VOCs, 1,4-dioxane. MNA

ERT01

Downgradient plume monitoring

Near comer of Mercury Drive at entrance of the
Nevins Active Senior Community, short slick up in
well pair, steel casing

20-150

Ground / Artesian

Grab

Field parameters, VOCs. 1,4-dioxane, MNA

LGSW

Downgradient plume monitoring

Former pumping well, look for old power drop to
electrical panel, well is immediately in front of
electrical panel

Ground / Artesian

Grab

Field parameters, VOCs, 1,4-dioxane, MNA

FW21D

Downgradient plume monitoring

Artesian well located at comer of Constitution Drive
and Capitol Hill Drive, look for old driveway in
wetland area, 1 -2' stick up

15-205

Ground / Artesian

Grab

Field parameters, VOCs, 1.4-dioxane, MNA

FW25

GMZ boundary monitoring

Right on Gilcreast Drive, Right on Ross Drive, look
for gated driveway after grev house (-500' down
Ross), well is a 3' PVC stick-up behind grey house,
pass area of tires and debris behind house

18-38

1.5

Pump 3 Well Volumes /
Wattera

Field parameters. VOCs, 1,4-dioxane, MNA

Tinkham Realty Water Supply
Well

Private Supply Well

Tap water sample from Tinkham Realty office on
McAllister Drive

' NA

Tap in kitchen

Grab (remove aerator)

VOCs

Notes:

1. Field parameters of groundwater quality monitored during sampling will include dissolved oxygen, oxidation-reduction potential, pH, specific conductivity, and temperature.

2. Method 8260B for Volatile Organic Compounds by Gas Chromaiography/Mass Spectrometry. USEPA Test Methods for Evaluating Solid Waste. Phvsical/Chemical Methods (SW-846) Third Edition. Final Update III.

3. MNA parameters include alkalinity and chloride.

4. Method SM2320B for total alkalinity. Standard Methods for the Examination of Water and Wastewater. 2320 B. 1998,20th Ed. American Public Health Association, Washingington,DC.

5. Method 4500C1E for Chloride. USEPA Test Methods for Evaluating Solid Waste. Phvsical/Chemical Methods fSW-846) Third Edition. Final Update HI.

6. Method SOMOI.X for 1,4-dioxane by SVOA.

1 of 1

-------
Table 5

Detected Volatile Organic Compounds in Surface Water
Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds

NHDES
WQCTS

Volatile Organic Compound Results ((ig/L) in Surface Water

SW1

10/22/1998

11/6/1998

5/10/1999

11/15/1999

5/17/2000

11/30/2000

5/14/2001

11/15/2001

5/21/2002

11/11/2002

5/30/2003

Tetrachloroethene

0.8

<2

<2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

2.7

<2

<2

2

<2



<2

<2

<2

4 ' '.'¦'

<2

2

1,1,1 -Trichloroethane

1

<2

<2 .

<2

<2

. -2"

<2

<2

<2

<2

<2

<2

cis-1,2-Dichloroethene

NS

<2

<2

2

<2

4

2

<2

<2

2

<2

<2

1,1-Dichloroethane

NS

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

.<2

1,2-Dichloroethane

0.38

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Methyl t-butyl ether

NS

30

< 10

< 10

< 10

< 10

<5

<5

<5

<5

<5

<5

1,4-Dioxane

NS

¦ NT ..

NT

NT

NT

NT

¦NT

NT

NT

NT

NT

NT

Notes:

L All concentrations in units of micrograms per liter ((ig/L).

2.	WQCTS indicates New Hampshire Department of Environmental Services Water Quality Criteria for Toxic Substances (WQCTS) for
protection of human health (water and fish ingestion).

3.	Only analytes detected in at least one sample and site contaminants of concern are reported here. For a complete list of analytes see
laboratory data sheets (Appendix B and Appendix C).

4.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

5.	Bold values indicate compounds that were detected above laboratory minimum detection limit.

6.	Laboratory analyses for volatile organic compounds, except 1,4-dioxane, were performed by Eastern Analytical Inc., Concord, New
Hampshire, using Environmental Protection Agency (EPA) Method 8260B. Laboratory analyses for 1,4-dioxane were performed by
Spectrum Analytical, Inc. (formerly Mitkem Laboratories), Warwick, Rhode Island using EPA Contract Laboratory Program SOMO.1.2
semivolatile organic analysis procedures, using Modified Analysis 1679.2.

7.	Tetrachloroethene and 1,2-dichloroethane were analyzed for and were not detected at concentrations greater than or equal to the
laboratory detection limit. For these compounds the laboratory detection limit exceeds the WQCTS.

8.	NS indicates that no WQCTS has been established for the compound.

9.	J qualifier indicates the result is estimated based on data validation criteria for this parameter.

10.	NT indicates that the sample was not tested for this parameter.

11.	Shaded values indicate compounds that were detected at concentrations greater than the WQCTS.

12.	Surface water from SW1 was collected on May 6, 2013 for analysis via 8260B and on May 7, 2013 for 1,4-dioxane analysis.

1 of 6

-------
Table 5

Detected Volatile Organic Compounds in Surface Water
Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds

NHDES
WQCTS

Volatile Organic Compound Results (|ig/L) in Surface Water

SW1 (continued)

11/6/2003

5/19/2004

11/3/2004

5/3/2005

11/18/2005

5/17/2006

11/8/2006

5/14/2007

11/14/2007

5/15/2008

11/6/2008

Tetrachloroethene

0.8

<2

<2

<2

<2

<2

<2

<2

<2

<2 '

<2

<2

Trichloroethene

2.7

<2

<2

<2

2

<2

2

<2

<2

<2

<2

<2

1,1,1 -Trich loroethane

1

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

cis-1,2-Dichloroethene

NS -

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethane

NS

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichloroethane

0.38

<2

<2

<2

<2

<2

<2

. <2

<2

<2

<2

<2

Methyl t-butyl ether

NS

<5

<5

<5

<5

<5

99

<5

<5

<5

<5

<5

1,4-Dioxane

NS

NT

NT

¦NT

NT

NT

NT

NT '¦

NT

NT

1 J

<2

Notes:

1.	All concentrations in units of micrograms per liter (|ig/L).

2.	WQCTS indicates New Hampshire Department of Environmental Services Water Quality Criteria for Toxic Substances (WQCTS) for
protection of human health (water and fish ingestion).

3.	Only analytes detected in at least one sample and site contaminants of concern are reported here. For a complete list of analytes see
laboratory data sheets (Appendix B and Appendix C).

4.	< indicates analyte not detected at a concentration above the specified laboratory reporting iimit.

5.	Bold values indicate compounds that were detected above laboratory minimum detection limit.

6.	Laboratory analyses for volatile organic compounds, except 1,4-dioxane, were performed by Eastern Analytical Inc., Concord, New
Hampshire, using Environmental Protection Agency (EPA) Method 8260B. Laboratory analyses for 1,4-dioxane were performed by
Spectrum Analytical, Inc. (formerly Mitkem Laboratories), Warwick, Rhode Island using EPA Contract Laboratory Program SOM01.2
semivolatile organic analysis procedures, using Modified Analysis 1679.2.

7.	Tetrachloroethene and 1,2-dichloroethane were analyzed for and were not detected at concentrations greater than or equal to the
laboratory detection limit. For these compounds the laboratory detection limit exceeds the WQCTS.

8.	NS indicates that no WQCTS has been established for the compound.

9.	J qualifier indicates the result is estimated based oh data validation criteria for this parameter.

10.	NT indicates that the sample was not tested for this parameter.

11.	Shaded values indicate compounds that were detected at concentrations greater than the WQCTS.

12.	Surface water from SW1 was collected on May 6, 2013 for analysis via" 8260B and on May 7, 2013 for 1,4-dioxane analysis.

2 of 6

-------
Table 5

Detected Volatile Organic Compounds in Surface Water
Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds

NHDES
WQCTS

Volatile Organic Compound Results (jig/L) in Surface Water

SW1 (continued)

SW2

5/21/2009

11/10/2009

5/10/2010

11/2/2010

5/26/2011

11/9/2011

5/10/2012

11/6/2012

5/6/201312

11/12/2013

9/4/1998

10/22/1998

T etrachloroethene

0.8

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

DRY

' <2

Trichloroethene

2.7

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

DRY

<2

1,1,1 -T richloroethane

1

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

DRY

<2

cis-1,2-Dichloroethene

NS

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

DRY

<2

1,1-Dichloroethane

NS

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

DRY

<2

1,2-Dichloroe thane

0.38

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

DRY

<2

Methyl t-butyl ether

NS

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

DRY

30

1,4-Dioxane

NS

4.1

<2

<2

<2

<2

0.23 J

0.15

0.46

0.72

1.6

NT

NT

Notes:

1.	All concentrations in units of micrograms per liter (ng/L).

2.	WQCTS indicates New Hampshire Department of Environmental Services Water Quality Criteria for Toxic Substances (WQGTS) for
protection of human health (water and fish ingestion).

3.	Only analytes detected in at least one sample and site contaminants of concern are reported here. For a complete list of analytes see
laboratory data sheets (Appendix B and Appendix C).

4.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

5.	Bold values indicate compounds that were detected above laboratory minimum detection limit.

6.	Laboratory analyses for volatile organic compounds, except 1,4-dioxane, were performed by Eastern Analytical Inc., Concord, New
Hampshire, using Environmental Protection Agency (EPA) Method 8260B. Laboratory analyses for 1,4-dioxane were performed by
Spectrum Analytical, Inc. (formerly Mitkem Laboratories), Warwick, Rhode Island using EPA Contract Laboratory Program SOMOl .2
semivolatile organic analysis procedures, using Modified Analysis 1679.2.

7.	Tetrachloroethene and 1,2-dichloroethane were analyzed for and were not detected at concentrations greater than or equal to the
laboratory detection limit. For these compounds the laboratory detection limit exceeds the WQCTS.

8.	NS indicates that no WQCTS has been established for the compound.

9.	J qualifier indicates the result is estimated based on data validation criteria for this parameter.

10.	NT indicates that the sample was not tested for this parameter.

11.	Shaded values indicate compounds that were detected at concentrations greater than the WQCTS.

12.	Surface water from SW1 was collected on May 6, 2013 for analysis via 8260B and on May 7, 2013 for 1,4-dioxane analysis.

3 of 6

-------
Table 5

Detected Volatile Organic Compounds in Surface Water
Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds

NHDES
WQCTS

Volatile Organic Compound Results (ng/L) in Surface Water

SW2 (continued)

11/6/1998

5/10/1999

5/17/2000

5/14/2001

11/15/2001

5/21/2002

11/11/2002

5/30/2003

11/6/2003

5/19/2004

11/3/2004

Tetrachloroethene

0.8

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

2.7

<2

3

4

<2

<2

10

<2

3

<2

<2

<2

1,1,1 -Trichloroethane

1

<2

<2

3

<2

<2

4

<2

<2

<2 \

<2

<2

cis-1,2-Dichloroethene

NS .

<2

2

4

<2

<2

4

<2

<2

<2

<2

<2

1,1-Dichloroethane

NS

<2

<2

<2

<2

' <2

<2

<2

<2

<2

<2

<2

1,2-Dichloroethane

0.38

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Methyl t-butyl ether

NS'

< 10

< 10

< 10

<5

<5

<5

<5

<5

<5

<5

<5

1,4-Dioxane

NS

NT

NT

NT

NT

NT

NT

NT

NT

NT

NT

NT

Notes:

1.	All concentrations in units of micrograms per liter (ng/L).

2.	WQCTS indicates New Hampshire Department of Environmental Services Water Quality Criteria for Toxic Substances (WQCTS) for
protection of human health (water and fish ingestion).

3.	Only analytes detected in at least one sample and site contaminants of concern are reported here. For a complete list of analytes see
laboratory data sheets (Appendix B and Appendix C).

4.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

5.	Bold values indicate compounds that were detected above laboratory minimum detection limit.

6.	Laboratory analyses for volatile organic compounds, except 1,4-dioxane, were performed by Eastern Analytical Inc., Concord, New
Hampshire, using Environmental Protection Agency (EPA) Method 8260B. Laboratory analyses for 1,4-dioxane were performed by
Spectrum Analytical, Inc. (formerly Mitkem Laboratories), Warwick, Rhode Island using EPA Contract Laboratory Program SOM01.2
semivolatile organic analysis procedures, using Modified Analysis 1679.2.

7.	Tetrachloroethene and 1,2-dichloroethane were analyzed for and were not detected at concentrations greater than or equal to the
laboratory detection limit. For these compounds the laboratory detection limit exceeds the WQCTS.

8.	NS indicates that no WQCTS has been established for the compound.

9.	J qualifier indicates the result is estimated based on data validation criteria for this parameter.

10.	NT indicates that the sample was not tested for this parameter.

11.	Shaded values indicate compounds that were detected at concentrations greater than the WQCTS.

12.	Surface water from SW1 was collected on May 6, 2013 for analysis via 8260B and on May 7, 2013 for 1,4-dioxane analysis.

4 of 6

-------
Table 5

Detected Volatile Organic Compounds in Surface Water
Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds

NHDES
WQCTS

Volatile Organic Compound Results (ng/L) in Surface Water

SW2 (continued)

5/3/2005

11/18/2005

5/17/2006

11/8/2006

5/14/2007

11/14/2007

5/15/2008

11/6/2008

5/21/2009

11/10/2009

5/10/2010

Tetrachloroethene

0.8

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

2.7

3

<2

2

<2

<2

<2

<2

<2

<2

<2

<2

1,1,1 -Trich loroethane

1

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

cis-1,2-Dichloroethene

NS

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethane

NS

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichloroe thane

0.38

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

. <2

Methyl t-butyl ether

NS

<5

<5

100

<5

<5

<5

<5

<5

<5

<5

<5

1,4-Dioxane

NS

NT

NT

NT

NT

NT

NT

2 J

<2

0.83 J

<2

<2

Notes:

1.	All concentrations in units of micrograms per liter (ng/L).

2.	WQCTS indicates New Hampshire Department of Environmental Services Water Quality Criteria for Toxic Substances (WQCTS) for
protection of human health (water and fish ingestion).

3.	Only analytes detected in at least one sample and site contaminants of concern aire reported here. For a complete list of analytes see
laboratory data sheets (Appendix B and Appendix C).

4.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

5.	Bold values indicate compounds that were detected above laboratory minimum detection limit.

6.	Laboratory analyses for volatile organic compounds, except 1,4-dioxane, were performed by Eastern Analytical Inc., Concord, New
Hampshire, using Environmental Protection Agency (EPA) Method 8260B. Laboratory analyses for 1,4-dioxane were performed by
Spectrum Analytical, Inc. (formerly Mitkem Laboratories), Warwick, Rhode Island using EPA Contract Laboratory Program SOM01.2
semivolatile organic analysis procedures, using Modified Analysis 1679.2.

7.	Tetrachloroethene and 1,2-dichloroethane were analyzed for and were not detected at concentrations greater than or equal to the
laboratory detection limit. For these compounds the laboratory detection limit exceeds the WQCTS.

8.	NS indicates that no WQCTS has been established for the compound.

9.	J qualifier indicates the result is estimated based on data validation criteria for this parameter.

10.	NT indicates that the sample was not tested for this parameter. -		

l l . Shaded values-indicate compounds that were detected at concentrations greatefthan the WQCTS.

12. Surface water from SW1 was collected on May 6, 2013 for analysis via 8260B and on May 7, 2013 for 1,4-dioxane analysis.

5 of 6

-------
Table5

Detected Volatile Organic Compounds in Surface Water
Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds

NHDES
WQCTS

Volatile Organic Compound Results (ng/L) in Surface Water

SW2 (continued)

11/2/2010

5/26/2011

11/9/2011

5/10/2012

11/6/2012

5/6/2013

11/12/2013

T etrachloroethene

0.8

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

2.7

<2

<2

<2

<2

<2

<2

<2

1,1,1 -T richloroethane

1

<2

<2

<2

<2

<2

<2

<2

cis-1,2-Dichloroethene

NS

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethane

NS

<2

<2

<2

<2

<2

<2

<2

1,2-Dichloroethane

0.38

<2

<2

<2

<2

<2

<2

<2

Methyl t-butyl ether

NS

<5

<5

<5

<5

<5

<5

<5

1,4-Dioxane

NS

<2

<2

0.2 J

0.14

0.37

0.74

1.4

Notes:

1.	All concentrations in units of micrograms per liter (ng/L).

2.	WQCTS indicates New Hampshire Department of Environmental Services Water Quality Criteria for Toxic Substances (WQCTS) for
protection of human health (water and fish ingestion).

3.	Only analytes detected in at least one sample and site contaminants of concern are reported here. For a complete list of analytes see
laboratory data sheets (Appendix B and Appendix C).

4.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

5.	Bold values indicate compounds that were detected above laboratory minimum detection limit.

6.	Laboratory analyses for volatile organic compounds, except 1,4-dioxane, were performed by Eastern Analytical Inc., Concord, New
Hampshire, using Environmental Protection Agency (EPA) Method 8260B. Laboratory analyses for 1,4-dioxane were performed by
Spectrum Analytical, Inc. (formerly Mitkem Laboratories), Warwick, Rhode Island using EPA Contract Laboratory Program SOM01.2
semivolatile organic analysis procedures, using Modified Analysis 1679.2.

7.	Tetrachloroethene and 1,2-dichloroethane were analyzed for and were not detected at concentrations greater than or equal to the
laboratory detection limit. For these compounds the laboratory detection limit exceeds the WQCTS. -

8.	NS indicates that no WQCTS has been established for the compound.

9.	J qualifier indicates the result is estimated based on data! validation criteria for this parameter.

10.	NT indicates that the sample was not tested for this parameter.

11.	Shaded values indicate compounds that were detected at concentrations greater than the WQCTS.

12.	Surface water from SW1 was collected on May 6, 2013 for analysis via 8260B and on May 7, 2013 for 1,4-dioxane analysis.

6 of 6

-------
Table 6

Detected Volatile Organic Compounds In Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (pg/L)





Source Area Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

NAI-M1





5/21/2002

6/25/2003

5/20/2004

5/3/2005

5/17/2006

6/14/2007

6/13/2007

5/14/2008

5/19/2009

6/10/2010

5/26/2011

5/9/2012

5/6/2013

04/04/14

Benzene

5

<1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

<1.

<1.

<1

<1

Acetone

700

<10

< 10

< 10

< 10

< 10

< 10

• <10

<10

< 10

< 10

< 10

<10

<10

<10

Chlorobenzene

NE

<2

< 2

< 2.

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

15

< 2

< 2

< 2

<2

<2

2

<2

<2

<2

<2

<2

<2

1,2-Dichloro benzene

600

2

< 1

< 1

< 1

< 1

<1

<1

< 1

< 1

< 1

< 1

<1

< 1

<1

1,4-Dichlorobenzene

76

<1

< 1

< 1

< 1

< 1

<1

<1

<1

<»1

< 1

<'-1

<1.

<1

< 1

1,1-Dichloroethane

81

2



3

< 2

<2

<2

7

6

2

3

<2

7

<2

<2

1,2-Oichloroethane

5

< 2

3

< 2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Diehloroethene

7

<1



< 1

< r

< 1

< 1

<1

< 1

<1

< 1

< 1

<1

<1

<1

cis-1,2-Oichloroethene

70

20

62

10

5

6

4

29

31

23

19

12

56

2

3

Diethyl ether

NE

< 5.

< 5

< 5

< 5

< 5

' < 5

<5

<5

<5

<5

<5 '

<5

<5

<5 -

Ethyl benzene

700

< 1

< 1

< 1

<1

< 1

<1

< 1

< 1

<1

<1

< 1

<1

- <1

< 1

iso-Propyl benzene

280

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

< 1

< 1

< 1

<1

< 1

< 1

n-Propyl benzene

NE

<1

< 1

< 1

<1

< 1

<1

< 1

<1.

< 1

< 1

<1

< 1

<1

< 1

Tetrachloroethene

5

2

75

. 9

3

3

2

5 .

3

<2

2

<2 .

3

<2

<2

Tetrahydrofuran (THF)

154

< 10

< 10

< 10

< 10

< 10

< 10

< 10

'< 10

<10 •

<10

<10

<10

< 10

< 10

Toluene

1000

<1

< 1

< 1 .

<1

< 1

<1

<1

<1

<1

<1

<1 .

<1

<1

< 1

1,1,1 -Trichloroethane

200

<2

140

6

< 2

< 2

<2

16

24

6

' 4

2

7

<2

<2

1,1,2-Trichloroethane

5

<2



< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

5

7

270

. 24

• « .

11

¦ 7 :'

.39 "

48

10

«

7

.21

3

S

1,2,4-Trimethyl benzene

NE

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

< 1

< 1

Vinyl chloride

2

. '4- '•

< 2

* 6.,=

. 4'

< 2

<2

<2

<2

<2

<2

<2

... >•„.

<2

<2

Xylenes (Total)

10000

<1

<2

< 2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Dichloroethene

100

<2

< 2

<2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Total VOCs



'37

580

58

17

20

13

96

114

41

41

21

97

S

6





























1,4-Dioxane

3

nt

NT

NT '

NT

NT

NT

NT-

<1R

<2.1

<2

<2

<0.1

0.12

0.56

Notes:

1.	All results are in micrograms per titer (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded vatues indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.				

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates hot tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.

1 of 17

G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire

Detected Volatile Organic
Compounds



Volatile Organic Compound Results (pg/L)



Source Area Groundwater

MCU
NHDES
AGQS

FW20



06/20/02

06/30/03

06/19/04

05/03/06

06/17/06

05/15/07

06/13/07

06/14/08

06/21/09

11/10/09

05/10/10

11/12/10

05/24/11

11/09/11

05/09/12

11/06/12

05/06/13

11/12/13

04/03/14

Benzene

5

3

4

1

2

5 .

2

< 1 .

3

3

3 -

4

7

2

2

2

5

3

3

2

Acetone

700

<10

<10

<10

<10

<10

< 10

< 10

< 10

< 10

< 10

<10

< 10

<10

< 10

<10

<10

<10

<10

<10

Chlorobenzene

NE

<2

<2

<2

<2

2

<2

<2

<2

<2

<2

2

<2

<2

<2

<2

<2

<2

<2

< 2

Chloroform

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

' <2

<2

<2

<2

< 2

1,2-Oichlorobeiuene

600

10

9

4

8

15

7

3

9

9

7

12

8

8

6

7

7

9

4

9

1,4-Dichloro benzene

75

2

2

<1

<1

2

2

1

2

2

1.

2

2

1

< 1

1

1

1

< 1

< 1

1,1-Dichloroethane

81

27

29

9

18

39

13

8

18

- 16

.13

22

16

13

12

12

11

14

7



1,2-Oichloroethane

6

.21

20

7

16

33

9

6

14

12

10

17

12

10 =

9

10

10

10

6



1,1-Oichtoroethene

7

1

1

<1

<1

2

< 1

<1:.

<1

< 1

<1

< 1

< 1

<1

< 1

<1

<1

<1

<1

< 1

cis-1,2-Oichloroethene

70

94

92

27

57

140

34

20

49

46

. 34

51

31

37

. 29

32

23

32

11



Diethyl ether

NE

7

6

<5

6

11

<5

<5

5

<5

<5

8

6

<5

<5

<5

<5

•< 5'

<5



Ethylbenzene

700

< 1

<1

<1

<1

<1

.< 1

<1

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

' < 1

< 1

<1.

< 1

iso-Propyl benzene

280

< 1

<1

<1

<1

<1

<1

<1

<1

< 1

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

<1

< 1

n-Propyt benzene

NE

< 1

<1

<1

<1

<1

< 1

<1

<1

<1

<1

< 1

<1

<1

<.1

<1

< 1

< 1

< 1

< 1

Tetrachloroethene

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

< 2 '

Tetrahydrofuran (THF)

164

<10

<10

<10

<10

<10

.<10

<10

<10 -

<10

< 10

.< 10

. <10

<10

<10

.<10 .

< 10

<10

< 10

<10

Toluene

1000

< 1

<1

<1

<1

<1

< 1

<1

<1

< 1

< 1

<1_

<1

< 1

<1

< 1

<1

<1

<1'

< 1

1,1,1 -Trichloroethane

200

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1,2-Trichloroe thane

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

_< 2

<2

<2

<2

<2

<2

<2

Trichloroethene

S

8

6

2

6

12 _

3

<2

4

4

3

4

3

3

<2

3

2

3

<2

3

1,2,4-Trimethyt benzene

NE

< 1

<1

1<

<1

<1

< 1

<1

<1

<1

<1 '

<1

<1

< 1

<1

< 1-

< 1

< 1

< 1

< 1

Vinyl chloride

. 2

46

35

13

33

81

17

11

• 35 '-j

" 26

26

42

25

23

20 .

16

22

19

>17 '

' 18 >

Xylenes (Total)

10000

<2

<2

<2

<2

<2

<2

<2

<2.

<2

<2

<2

<2

<2

<2

. <2

<2

<2

<2

<2

trans-1,2-Dichloroethene

100

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

• <2

<2

<2

<2

<2

Total VOCs



221

204

63

145

349

87

49

139

114

96

170

109

99

78

83

81

91

48

104









































1,4-Oioxane

3

NT | NT | NT | NT | NT | NT | NT | 140J J" ,160 |. 62 | 120. 1 ,71- | 98 D | 39DJ I , 32 1 ! 81 I 130 1 75 I 100 ;

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs wera detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.	2 of 17	G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (tig/L)





Source Area Groundwater

Detected Volatile Organic
Compounds

MCU
NHDES
AGQS

OW2D





6/20/2002

11/1/2002

6/30/2003

11/6/2003

11/6/2003-Dup

5/19/2004

11/3/2004

11/3/2004-Dup

6/3/2005

11/18/2005

11/18/2005-Dup

5/17/2006

11/8/2006

6/14/2007

11/14/2007

Benzene

5

4

6

4

4

4

3

4

4

< 1

3

3

2

2

1

2

Acetone

700

<10

20

< 10

<10

< 10

< 10

< 10

< 10

< 10

< 10

<10

40

< 10

30

< 10

Chlorobenzene

NE

6

<2

4

4

4

5

3

3

<2

4

4

3

3

3

3

Chloroform

NE

<2

<2

< 2

< 2

<2

< 2

< 2

< 2 .

<2

< 2

<2

< 2

< 2

<2

<2

1,2-Dichloro benzene

600

40

37

36

42

42

39

32

32

< 1

38

36

36

40

36

28

1,4-Olchloro benzene

75

4

3

3

3

4

4

3

3

< 1

4

3

3

4

3

3

1,1-Dichloroethane

81

49

52

55

54

55

47

43

42

< 2

38

37

34

31

31

29

1,2-Dichloroethane

5

61

46

48

- ' 62

84 -

43

36

. 35

< 2

33



* 28

29

,26

24

1,1-Oichloroethene

7

3

3

4

3

3

3

2

2

< 1

3

3

1

2

2

2

cis-1,2-Dichloroethene

70

' 480 -

• 300. :

480'

310

320 .

350

290

' .280

8

' 260

250 ¦

210

210

220

160

Diethyl ether

NE

<5

9

8

9

9

7

7

6

< 5

6

6

6

6

6

6

Ethyl benzene

700

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

iso-Propyl benzene

260

3

3

2

2

2

3

2

2

< 1

2

2

1

2

1

1

n-Propyl benzene

NE

<2

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

Tetrachloroethene

5



' '5

- * 8

" ¦

5

. 7

- 6

S

< 2

7 .

6 : -:

7

7 .

7

4

Tetrahydrofuran (THF)

164

<10

' <10

< 10 '

<10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

<10

< 10

Toluene

1000

<1

< 1

< 1

<1

< 1

< 1

< 1

< 1

< 1

< 1

. < 1

< 1

< 1

<1

<1

1,1,1-Trichloroethane

200

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

<2

< 2

<2

<2

< 2

<2

<2

1,1,2-Trichloroethane

5

<2

<2

< 2

<2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

Trlchloroethene

5

39

. .19

. , '26;.

¦ i22- '

.¦ .23:

29

.19 •



< 2

23

'21'.. ;

21

20=.

19

* 11

1,2,4-Trimethyl benzene

NE

<1

< 1

< 1

< 1

< 1

< 1 •

< 1

<1

< 1

<.1

< 1

< 1

< 1

<1

< 1

Vinyl chloride

2

* T 32 •/



, 23a



; , 20 - '

»

. 18

<15

< 2

13

" ' • ' • .""12''

¦ io ;

12

9

.11

Xylenes (Total)

10000

<2

<2

< 2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

< 2

<2

<2

lrans-1,2-Dichloroethene

100

<2

2

< 2

2

3

< 2

< 2

< 2

< 2

< 2

<2

16

<2

4

<2

Total VOCs



680

532

704

539

555

570

467

454

8

' 439

420

420

368

396

284























1,4-Dioxane

3

NT

NT

NT

NT

' NT

NT

NT

NT

NT

NT

NT

NT

NT

NT

NT

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists forthal compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

6. Total VOCs include ail detected VOCs except 1,4-Dioxane. BOL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.	 		 		 				

10.	J indicates that the result is estimated based on data velidation criteria.

11.	NT indicates not tested for this parameter.

12.	O indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.

3 of 17

G:\40814\002\5YR Tables FiguresVTable 6 - 2014-0728 Historical groundwater concentrations.pctf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (M9/U





Source Area Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS











OW2D

• Page 2















11/14/2007-Dup

5/14/2008

5/14/2008-Dup

11/6/2008

5/21/2009

5/21/2009-Dup

11/10/2009

11/10/2009-Dup

5/10/2010

5/10/2010-Dup

11/9/2010

11/9/2010-Dup

Benzene

6

2

1

1

<1

< 1

1

1

<1

< 1

< 1

1

1

Acetone

700

<10

30

30

<10

<10

<10

< 10

< 10

20

30

20

20

Chlorobenzene

NE

3

3

3

2

3

3

<2

<2

3

3

2

2

Chloroform

NE

<2

<2

<2

<2

<2

<2

<2

. <2

<2

<2

<2

<2

1,2-Dichloro benzene

600

29

31

30

27 '

36

37

24

24

36

36

24

24

1,4-Dichlorobenzene

76

3

3

3

3

4

4

2

2

4

4

3

3

1,1-Dichloroethane

81

29

24

24

21

22

22

18

19

23

22

19

19

1,2-Dichloroethane

8

- 25

20

20

18

19 '

19

16

16

19

19

*16

i*

1,1-Dichloroethene

7

2

1

1

1

1

2

1

1

1

1

< 1

'< 1

cis-1,2-Oichloroethene

70

•160

150

150

160

170

170'

120

120

130

130

100

. no.

Diethyl ether

NE

6

<5

<5

< 5

<5-

<5 '

<5

<5

<5

<5

< 5

<5

Ethyl benzene

700

<1

< 1

<1

<1

<1

<1

<1

< 1

< 1 =

< 1

< 1

< 1

iso-Propylbenzene

280

1

< 1

<1

<1

<1

<1

< 1

< 1

< 1

< 1

<1.

< 1

n-Propyfbenzene

NE

<1

< 1

< 1

< 1

< 1

<1.

< 1

<1.

< 1

< 1

< 1

' <1

Tetrachloroethene

6

4

6

6

4



6

4

4

6

6

3 .

3

Tetrahydrofuran (THF)

154

<10

<10

<10

<10

<10

<10

< 10

. <10

<10

. < 10

. <10

<-10

Toluene

1000

< 1

<1

< 1

<1

< 1

< 1

< 1

< 1

< 1

<1

<1

< 1

1,1,1 -Trichloroethane

200

<2

<2

<2

<2

<2

<2

<2

<2.

<2

<2

<2

<2

1,1,2-Trichloroethane

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

6

12

14

14

13

16

17

11

12

14

14

9

9

1,2,4-Trimethyt benzene

NE

<1

<1

<1

< 1

<1

<1

<1

<1

< 1

<1

<1

< 1

Vinyl chloride

2

11

6

5

7 .

9

9

7

7

9

9

6

6

Xylenes (Total)

10000

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

- <2 .

trans-1,2-Oichloroethene

100

<2

5

3

<2

<2

<2

<2

<2

<2

3

<2

<2

Total VOCs



287

293

289

256

295

290

203

205

265

277

203

213























1,4-Dioxane

3

NT

200 J ,

220 J

350

190 '

180

120 D

110

110

140

100 D

98 D

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< Indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL Indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists forthat compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs Include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.
9^ R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample .that was diluted prior to analysis

HALEY ALDRJCH, INC.	4 of 17	G:\40814\002\5YR Tables FiguresVTable 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (M9/1)





Source Area Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

OW2D -page3





5/26/2011

5/26/2011-Dup

11/9/2011

11/9/2011-Dup

5/10/2012

5/10/2012-Dup

11/6/2012

11/6/2012-Oup

5/6/2013

5/6/2013-Dup

11/12/2013

4/3/2014

4/3/2014-Dup

Benzene

5

<1

< 1

< 1

< 1

<1

<1

<1

< 1

<1

<1

<1

<1

<1

Acetone

700

<10

<10

< 10

< 10

<10

< 10

<10

< 10

< 10

<10

<10

<10

< 10

Chlorobenzene

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichlorobenzene

600

20

22

18

18

18

18

20

20

16

15

15

14

14

1,4-Oichtorobenzene

75

2

2

2

2

2

2

2

2

2

2

2

2

2

1,1-Oichloroethane

81

13

13

14

14

12

12

13

13

8

8

13

8

8

1,2-Oichtoroethane

5

'11 v

'12 '>

' 12. •;

'12

12 -

•' '12 --

••'12 .

•,12 "



: 8 - /.<

MS r

<7.

7

1,1-Oichloroethene

7

<1

<1

<1

< 1

< 1

<1

< 1

<1 '

<1

<1

< 1

<1

< 1

cis-1,2-Dichloroethene

70

86

88



83

80

80.

78 •

77

47

45

72

46

46

Diethyl ether

NE

<5

<5

< 5

< 5

< 5'

<5

<5

<5

<5

<5

<5

< 5

<5

Ethyl benzene

700

<1

< 1

<1

<1

< 1

<1

< 1

< 1

<1

<1

<1

<1

<1

iso-Propylbenzene

280

<1

<1

<1

<1

< 1

<1

< 1

< 1

< 1

<1

<1

. <1

<1

n-Propylbenzene

NE

<1

<1

<1

<1

< 1

< 1

<1

< 1

<1.

<1

<1

< 1

<1

Tetrachtoroethene

5

3

3

3

3

3

3

<2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

<10

<10

<10

< 10

<10

<10

<10

< 10

<10

<10

<10

<10

<10

Toluene

1000

<1

<1

< 1

< 1

< 1

< 1

<1

<1

<1 >

<1

<1

< 1

<1

1,1,1 -Trichtoroethane

200

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1,2-Trichloroethane

6

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2-

<2

<2

Trichloroethene

5

• 8 *

•.* "8

' 7

'7- '

>8

.. ¦ '6.

' 8«

¦«

. ;5

¦5

6

4

4

1,2,4-Trimethyl benzene

NE

<1

<1

< 1

< 1

<1

<1

<1

<1

<1

< 1

< 1

< 1

• <1

Vinyl chloride

2

¦ 6

6

5

6

- 4

- -'4 -

4;



2

2 "

5

3



Xylenes (Total)

10000

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Dichloroethene

100

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Total VOCs



148

154

143

144

139

139

133

135

89

85

126

84

84

















1,4-Dioxane

3

, •'90D ,

99 D

46 DV

*67 D J -

32

32

74

"69

80

73

, 120

- «

43

Notes:

1.	All results are in micrograms per Irter (pg/L).

2.	< indicates analyte hot detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.
	9..R indicates that the result Is rejected based on data validation criteria.		.	—	—•

10.	J indicates that the resuft is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.

5 of 17

G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results { Mfl/U





Overburden Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

FW25





5/16/2002

5/30/2003

6/20/2004

6/3/2005

6/18/2006

6/16/2007

6/13/2007

6/16/2008

5/21/2009

6/12/2010

5/24/2011

6/9/2012

6/7/2013

4/3/2014

Benzene

5

< 1

< 1

< 1

< 1

< 1

<1

<1 ,

<1 .

<1

<1

<1

<1

<1

< 1

Acetone

700

<10

< 10

< 10

< 10

< 10

<10

<10

< 10

<10

. < 10

<10

<10

<10

<10

Chlorobenzehe

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichloro benzene

600

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

< 1

< 1

<1

<1

<1

<1

1,4-Otchlorobenzene

75

<1

< 1

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

< 1

< 1

<1

<1

1,1-Oichloroethane

81

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichloroethane

6

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethene

7

<1

< 1

< 1

< 1

<1

<1

<1

<1

<1

<1

<1

<1

<1

<1

cis-1,2-Oichloroethene

70

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Diethyl ether

NE

<5

< 5

< 5

< 5

< 5

<5

<5

<5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

<1

< 1

< 1

< 1

<1

<1*

<1

<1

<1

<1

<1

< 1

< 1

< 1

iso-Propyt benzene

280

<1

< 1

< 1

< 1

< 1

<1

<1

< 1

<1

<1

<1

<1

< 1

<1

n*Propy1 benzene

NE

<1

< 1

< 1

< 1

< 1

< 1

<1

<1 ¦

-<1.

<1

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site* Londonderry, New Hampshire





Volatile Organic Compound Results (iig/L)





Source Area Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

NAI-K2





6/26/2003

6/20/2004

6/3/2005

6/17/2006

6/14/2007

6/13/2007

8/14/2008

5/19/2009

11/11/2009

5/11/2010

11/12/2010

5/25/2011

11/9/2011

6/9/2012

11/6/2012

6/6/2013

11/12/2013

4/4/2014

Benzene

S

9

4

3

1

<1

<1 '

2

1

<1

<5

<1

<5

<5

< 1

<5

<1

<1 .

<1

Acetone

700

<10

<10

<10

<10

<10

< 10

< 10

<10

< 10

<50

<10

<50

<50

<10

<50

<10

<10

< 10

Chlorobenzene

NE

• <2

<2

<2

<2

<2

<2

<2

<2

<2

<5

<2

<5

<5

<2

<5

<2

<2

<2

Chloroform

NE

12

7

6

3

3

2

8

3

<2

<5

<2

<5

<5

<2

<5

3

3

<2

1,2-Dichloro benzene

600

20

12

9

4

3

3

6

4

4

< 5

2

8

7

4"

7

7

6

3

1,4-Dichlorobenzene

78

<1

<1

<1

<1

<1

<1

< 1

<1

<1

<5

<1

<5

<5

<1

<5

<1

<1

<1

1,1-Dichloroethane

81

56

29 .

26

12

10

8

16

16

17

47

9

45

40

24

25

35

32

23

1,2-Dichloroetharte

5

6

3

2

<2

<2

<2

<2

<2

<2

<5

<2

<5

<5

<2 .

<5

<2

<2

<2

1,1-Oichloroethene

7

17

. 9

<8

4

3

2

4

4

3

6

<1

<5

<5

1

<5

2

4

1

cis-1,2-Dichloroethene

70

- 920

390

290 '

130

83

66

190 ;

220 ¦

230

*880

120 1

. 520

370 1

• '190 * -

_ . 220

: 260

270

190

Diethyl ether

NE

<5

<5

<5

<5

<5

<5

<5

<5

<5

<30

<5

<30

< 30

<5

<30

<5

<5

<5

Ethyl benzene

700

<1

<1

<1

<1

< 1

< 1

< 1

<1

<1

<5

< 1

<5

<5

<1

<5

<1

< 1

< 1

iso-Propyl benzene

260

<1

<1

<1

<1

< 1

<1

<1

' <1

<1

<5

< 1

<5

<5

<1

<5

<1

<1

< 1

n-Propyl benzene

NE

<1

<1

<1

<1

< 1

<1

<1

<1

< 1

<5

<1

<5

<5

< 1

<5

< 1

< 1

< 1

Tetrachloroethene

6

<2

61

88

29

• . 27

23

40

47

32

• 87 .

;ir

"49

30

21

26

'31

37

,23

Tetrahydrofuran (THF)

154

<10

<10

<10

<10

<10

<10

<10

< 10

<10

<50

<10

<50

<50

<10

<50

<10

< 10

< 10

Toluene

1000

<1

<1

1

<1

<1

<1

<1

<1

<1

<5

<1

<5

<5

<1

<5

< 1

< 1

<1

1,1,1-Trichloroethane

200

310

160

120

45

47

42

98

79

60

96

17

74

43

13

16

40

41

21

1,1,2-Trichloroethane

5

• .14 -

7

6

<2

<2

<2

3

4

2

• , 8

<2

<5

<5

<2

< 5

<2

<2

" <2

Trichloroethene

5

87

300

250

140

110

110

- 180

230

180 *

240

•42.

-140'.

92

40

49" .

71-

88

54

1,2,4-Trimethyt benzene

NE

<1

<1

<1

<1

< 1

< 1

1

<1

<1

<5

<1

<5

<5.

< 1

<5

<1

< 1

<1

Vinyl chloride

2

18 *

9 .

13

9 , '

7

8

6

7

9

20

'3

<10

< 10

7 '.

10

7

20

7

Xylenes (Total)

10000

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Dich!oroethene

100

11

5

4

<2

<2

<2

<2

<2

<2

<5-

<2

<5

<5

<2

<5

6

4

<2

Total VOCs



1460

986

794

377

293

263

551

615

537

1032

204

836

582

300

353

462

507

322









































1,4-Dioxane

3

NT

NT

NT

NT

NT

NT

1 J

<2

<2

<2

<2

<2

0.21 J

<0.1

0.66

0.45

0.82

<0.1

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists forthat compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

6. Total VOCs include all detected VOCs except 1 .^Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limitr

9.	R indicates that the rasutt is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDR1CH, INC.

7 of 17

G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results ( pg/L)





Source Area Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

DVE-7





6/25/2003

6/20/2004

6/3/2006

6/3/2006

6/14/2007

6/13/2007

6/14/2008

6/21/2009

6/11/2010

6/24/2011

6/10/2012

5/7/2013

4/2/2014

Benzene

- 5

< 1

< 1

< i

. < 1

<1

<1

< 1

<1

<1

< 1

< 1

< 1

<1

Acetone

700

< 10

< 10

< 10

< 10

<10

<10

< 10

<10

<10

<10

< 10

< 10

<10

Chlorobenzerte

NE

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichloro benzene

600

< 1

< 1

< 1

< 1

< 1

<1

< 1

<1

<1

<1

<1

< 1

< 1

1,4-Oichtorobenzene

76

< 1

< 1-

< 1

< 1

<1

< 1

< 1

<1

<1

<1

<1

<1

< 1

1,1-Dichloroethane

61

< 2

2

< 2

<2

<2

<2

<2

2

6

10

10

14

6

1,2-Oichloroethane

5

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Oichloroethene

7

< 1

< 1

< 1

< 1

< 1

<1

< 1

<1

<1

< 1

< 1

< 1

< 1

cis-1,2-Dichloroethene

70

22

19

3

<2

2

<2

4

30

87

- 96

42

76

46

Diethyl ether

NE

< 5

< 5

< 5

< 5

<5

<5

< 5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

< 1

< 1

<1

isorPropyl benzene

280

< 1

< 1

< 1

< 1

< 1

< 1

• <.1

<1

<1

< 1

<1

< 1

<1

n-Propyi benzene

NE

< 1

< 1

< 1

< 1

<1

< 1

< 1 -

<1

<1

< 1

< 1

<1

<1

Tetrachloroethene

5

< 2

21



S

17



9

10

21

19

12

IS

12

Tetrahydrofuran (THF)

164

16

< 10

< 10

< 10

<10

<10

< 10

<10

<10

<10

<10

< 10

<10

Toluene

1000

< 1

< 1

< 1

< 1

<1

<1

< 1

<'1

< 1

. <1

< 1

< 1

< 1

1,1,1 -Trichloroethane

200

20

30

8

4

6

4

6

12

30

20

6

16

8

1,1,2-Trichloroethane

5

< 2

< 2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

S

36

67

9

5

9

7

¦13

11

29

28

9

19

11

1,2,4-Trimethyibenzene

NE

< 1

< 1

< 1

< 1

< 1

<1

< 1

< 1

< 1

<1

<1

< 1

< 1

Vinyl chloride

2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Xylenes (Total)

10000

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Dichloroethene

100

< 2

< 2

< 2

< 2

<2

<2

<2 .

<2

3

<2

<2

<2

<2

Total VOCs



92

129

29

14

34

24

32

65

178

173

79

140

82































1,4-Dioxane

3

NT

NT

NT

NT

NT

NT

2J

<2.1

<2

<2

<0.1

<0.1

<0.1

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs inctude all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	Dindicates sampte that was diluted prior to analysis

HALEY ALDRICH, INC.	8 of 17	G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (pg/L)





Source Area Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

DVE-3





6/21/2002

6/2S/2003

5/20/2004

5/3/2005

5/17/2006

6/14/2007

6/13/2007

6/14/2008

5/21/2009

6/11/2010

6/26/2011

5/10/2012

5/7/2013

4/2/2014

Benzene

5

< 1

< 1

< 1

< 1

< 1

. <1

<1

<1

<1

<1

<1

<1

<1

<1

Acetone

700

<10

< 10

< 10

<10

< 10

<10

<10

<10

<10

<10

<10

<10

< 10

<10

Chlorobenzene

NE

<2

< 2

< 2

< 2

< 2

8

6

4

5

6

9

8

9

3

Chloroform

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichloro benzene

600

< 1

2

1

< 1

< 1

8

6

5

4

3

6

4

3

<1

1,4-0ichlorobenzene

75

< 1

6

2

< 1

< 1

8

5

3

4

4

6

6

6

< 1

1,1-Oichioroethane

81

<2

< 2

<2

< 2

< 2

<2

<2

<2

<2

<2

<2

•< 2

<2

<2

1,2-Oichloroethane

6

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-DichIoroethene

7

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

<1

< 1

< 1

<1

<1

< 1

cis-1,2-Dichloroethene

70

5

3

11

6

<2

4

3

2

4

6

4 *

3

3

<2

Diethyl ether

NE

<5

< 6

< 5

< 5

< 5

<5

<5

<5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

< 1

< 1

<1

<1

iso-Propyl benzene

280

<1

< 1

' < 1

< 1

< 1

<1

<1

<1

<1

<1

<1

< 1

<1

<1

n-Propylbenzene

NE

<1

< 1

< 1 "

< 1

< 1

<1

<1

<1

<1

< 1

<1

<1

< 1

<1

Tetrachloroethene

5

<2

< 2

2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

< 10

180

< 10

< 10

< 10

<10

< 10

<10

<10

<10

<10

<10

<10

<10

Toluene

1000

<1

< 1

< 1

< 1

< 1

•<1

<1

<1

<1

<1

< 1

<1

• <1

<1

1,1,1-Trichloroethane

200

<2

< 2

<2

< 2

< 2

<2

<2

<2

<2

3

<2

<2

<2

<2

1,1,2-Trichloroethane

5

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

5

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

3

<2

<2

<2

<2

1,2,4-Trimethyl benzene

NE

<1

3

<1

< 1

< 1

2

1

< 1

< 1

<1

<1

<1

<1

< 1

Vinyl chloride

2

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2 .

<2

Xylenes (Total)

10000

<2

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Dichioroethene

. 100

<2

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Total VOCs



5

193

16

6

BDL

. 26

20

14

17

24

24

• 21

21

3

































1,4-Dioxane

3

NT'

NT

NT

NT

NT "

NT

NT

< 1 R

<2.1

<2

<2

<0.1

0:23

<0,1

Notes:

1.	All results are in micrograms per liter (jjq/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDR1CH, INC.

9 of 17

G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)
' 2014 Five-Year Review Report
Tinkham Garage Site, Londonderry, New Hampshire

Oetected Volatile Organic
Compounds



Volatile Organic Compound Results (i>g/L)



Bedrock Groundwater

MCU
NHDES
AGQS

FW11D



5/20/2002

6/30/2003

6/19/2004

6/3/2005

5/17/2006

5/15/2007

6/13/2007

11/14/2007

6/16/2008

6/20/2009

11/10/2009

6/10/2010

11/9/2010

6/24/2011

11/9/2011

6/9/2012

11/6/2012

6/6/2013

11/12/2013

4/3/2014

Benzene

6

< 1

<1

<1

<1

<1

<1

2

3

2

4

2

< 1

<1 .

2

2

2

<1

1

2

1

Acetone

700

< 10

<10

<10

<10

<10

<10

<10

<10

<10

< 10

<10

10

<10

<10

<10

<10

<10

< 10

<10

<10

Chlorobenzene

NE

2

<2

<2

<2

<2

<2

<2

<2

<2 -

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2..

Chloroform

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2 .

<2

<2

1,2-Dichlorobenzene

600

1

<1

<1

1<

<1

<1

5

6

6

12

6

6

3

7

8

7

7

6

8

6

1,4-Dichloro benzene

75

<1

<1

<1

<1

<1

<1

<1

< 1

<1

1

<1

<1

< 1

< 1

<1

< 1

< 1

< 1

< 1

<-1

1,1-Dichloroetftane

81

7

2

3

<2

3

<2

12

19

16

24

13

16

11

17

18

16 .

13

10

16

12

1,2-Oichloroethane

5

4

<2

<2

<2

<2

<2

7

10

6

12

¦ 6

6

<2

8

'8

7

6

6

8

5

1,1-Dichloroethene

7

<1

<1

<1

<1

<1

<1

<1

1 -

1

1

. < 1

1

1

2

< 1

< 1

< 1

< 1

-<1

<1

cis-1,2-Oichloroethene

70

16

6

9

3

9.

<2

24

31

28

51

23

30

22

35

34

30

30

20

26

26

Diethyl ether

NE

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

<5

< 5

< 5

<5

<5

Ethyl benzene

700

< 1

<1

<1

<1

<1

<1

<1

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

iso-Propyl benzene

280

< 1

<1

<1

<1

<1

< 1

<1

< 1

<1

< 1

. <1

< 1

< 1

< 1

< 1

< 1

*< 1

<1

<1

<1

n-Propyl benzene

NE

< 1

<1

<1

<1

<1

<1-

<1

<1

<1

< 1

< 1

<1

<1

• <1

< 1

<1

. <1

<1

<1

• <1

Tetrachioroethene

5

<2

<2 -

<2

<2

<2

<2

- <2

.. <2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2 -

Tetrahydrofuran (THF)

154

10

<10

<10

<10

<10

< 10

10

20

20

20

10

< 10

<10

10

- <10

<10

<10

<10

< 10

<10

Toluene

1000

<1

<1

1<

<1

<1

<1

< 1

<1

<1

<1 .

< 1.

<1

<1.

<1

<1

<1

<1

< 1

<1

< 1

1,1,1-Trichioroethane

200

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2 .

<2

<2

<2

<2

<2

<2

<2

1,1,2-Trichloroethane

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

.<2

Trichloroethene

5

16

7

9

•6

7

3

6

8

10

7

6

27

17

11

7

7

7

6

4

4

1,2,4-Trimethyl benzene

NE

<1

<1

1<

<1

<1

< 1

< 1

<1

<1

<1

<1

<1

<1

< 1

<1

< 1

< 1

< 1

< 1

<1 .

Vinyl chloride

2

8 ,

<2

<2

<2

3

<2

26

27

37

46

23

16

8

34

29

23

18

13

27

19

Xylenes (Total)

10000

<2

<2

<2

<2

<2

<2

<2

- <2

.<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2,

trans-1,2-Oichloroethene

100

<2

<2

<2

<2

<2

-< 2

<2

2

<2

3

<2

<2 .

<2

2

<2

2 .

2

<2

2

<2

Total VOCs



64

15

21

8

22-

3

94

129

127

174

89

109

62

128

106

93

83

61

93

12'











































1,4-Dioxane

3

NT | NT | NT | NT | NT | NT | NT | NT | 460 j | 600 I 210 D | 230 | 110 D | 300 O , | 160 D J | 120 | 240 | 270 | 480 | 240

Notes:

1.	All results are in micrograms per titer (pg/L).

2.	< indicates analyte not detected at a concentration above Uie specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCI indicates Maximum Contaminant Concentration as established by the USEPA underthe Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criterta.

10.	J indicates that the result is estimated based on data validation criteria:

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to" analysis

HALEY ALDR1CH, INC.

10of 17

G:\40814\002\5YR Tables FiguresYTable 6 - 2014-0728 Historical groundwater concentrations.pdf.xjsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results { pg/L)





Bedrock Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDE8
AGQS

ERT01





5/17/2002

6/30/2003

5/19/2004

5/3/2005

6/18/2006

5/14/2007

6/16/2008

5/21/2009

5/11/2010

5/25/2011

5/10/2012

5/7/2013

3/31/2014

Benzene

6

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

Acetone

700

< 10

< 10

< 10

< 10

< 10

<10

< 10

<10

<10

< 10

< 10

<10

< 10

Chlorobenzene

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichlorobenzene

600

<1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

<1

< 1

1,4-Dichloro benzene

75

<1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

< 1

<1

<1

1,1-Oichloroethane

81

6

2

< 2

2

< 2

2

2

<2

<2

<2

<2

2

<2

1,2-Oichloroethane

S

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethene

7

2

< 1

< 1

< 1

< 1

' <1

<1

<1

<1

<1

< 1

< 1

<1

cis-1,2-Oichloroethene

70

22

12

11

13

12

16

16

12

15

18

14

21

16

Diethyl ether

NE

<5

< 5

< 5

< 5

< 5

<5

< 5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

< 1 •

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

< 1

<1

<1

iso-Propyl benzene

280

< 1

< 1

< 1

< 1

< 1

<1

<1

<1 '

<1

<1

< 1

<1

< 1

n-Propylbenzene

NE

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

<1

< 1

< 1

<1

<1

Tetrachtoroethene

5

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

<10

< 10

< 10

< 10

< 10

<10

< 10

<10

<10

<10

<10

< 10

<10

Toluene

1000

< 1

< 1

< 1

< 1

< 1

<1^

<1

<1

< 1

< 1

<1

<1

< 1

1,1,1 -Trichloroethane

200

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,1,2-Trichtoroethane

6

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

6

,29

18

2

-"15 '

10

9 •

.10..

,-.*.8"..

'

.7

4

6

4

1,2,4-Trimethyl benzene

NE

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

Vinyl chloride

2

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Xylenes (Total)

10000

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Oichloroethene

100

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Total VOCs



58

32

13

30

22

< 20

27

17

21

25

18

29

20



























1,4-Dioxane

3

NT

NT

NT

NT

NT

NT

ju'

1«

17.

20

,8.3 '

14 "

13

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration asestablished by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

6. Total VOCs include ail detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on deta validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.	11 of 17	G:\40814\002\5YR Tables Figures\Tab!e 6 - 2014-0728 Historical groundwater concentrations.pdf.xisx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results ( M9/L)





Bedrock Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

LGSW





5/20/2002

5/30/2003

8/2/2004

5/3/2005

6/18/2008

5/14/2007

5/15/2008

6/20/2009

5/11/2010

5/26/2011

5/10/2012

6/7/2013

3/31/2014

Benzene

5

9

11

9

8

9-

8

8

8

7 •

7

6

8

7

Acetone

700

<10

<10

< 10

< 10

< 10

< 10

<10

<10

<10

<10

<10

<10

< 10

Chlorobenzene

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

- <2

<2

Chloroform

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichlorobenzene

600

<1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

< 1

< 1

< 1

1,4-Oichlorobenzene

75

<1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

< 1

<1

<1

- <1

1,1-Oichloroetharie

61

5

5

4

4

4

4

3

3

3

3

2

3

2

1,2-Dichloroethane

5

2

2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethene

7

< 1

< 1

< 1

< 1

< 1

<1 -

<1

< 1

<1

<1

< 1

< 1

< 1

cis-1,2-Oichloroethene

70

2

2

2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Diethyl ether

NE

<5

< 5

< 5

< 5

< 5

<5

<5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

2

< 1

< 1

< 1

< 1

< 1 •'

< 1

< 1

<-1

<1

<1

<1

< 1

iso-Propyl benzene

280

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

< 1

<1

< 1

<1

n-Propyt benzene

NE

< 1

< 1

< 1

< 1

< 1

<1

<1

< 1

<1

<1

<1

<1

< 1

Tetrachloroethene

5

<2

< 2

< 2

< 2

< 2

<2

:• <2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

<10

< 10

< 10

< 10

< 10

<10

<10

-<10

.<10

< 10

<10

<10

<10

Toluene

1000

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

< 1

< 1

1,1,1-Trichloroethane

200

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2-

<2

1,1,2-Trichloroethane

5

<2

< 2

< 2

< 2

< 2

<2

<2*.

<2

<2

<2

<2

<2 .

<2

Trichtoroethene

5

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

. <2

<2

<2

<2

1,2,4-Trimethyl benzene

NE

1

< 1

< 1

< 1

< 1

<1

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results ( pg/L)





Bedrock Groundwater

Detected Volatile Organic
Compounds'

MCL/
NHDES
AGQS

FW21D





5/16/2002

5/30/2003

5/18/2004

5/3/2005

5/18/2006

5/15/2007

5/15/2008

5/21/2009

5/11/2010

5/25/2011

5/10/2012

5/7/2013

3/31/2014

Benzene

5



¦ 5 ¦ ;

4

4

4

4

3

3

3

3

3

3

3

Acetone

700

<10

<10

< 10

< 10

< 10

<10

<10

<10

<10

<10

< 10

<10

<10 '

Chlorobenzene

NE

<2

< 2

< 2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichloro benzene

600

28

21

21

20

20

19

19

20

18

19

14

16-

13

1,4-Dichloro benzene

75

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

< 1

<1

<1

<1

1,1-Dichloroethane

81

34

26

21

22

21

20

19

17

18

17

13

16

14

1,2-Dichloroethane

S

<2

< 2

< 2

< 2

<-2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Oichloroethene

7

<1

< 1

< 1

< 1

<•1

<1

.< 1

<1

< 1

< 1

<1

<1

< 1

cis-1,2-Dichloroethene

70

20

21

18

19

18

17

14

15

13

14

11

13

11

Diethyl ether

NE

6

< 5

< 5

< 5

< 5

<5

<5

<5

<5

<5

<5

<5

< 5

Ethyl benzene

700

99

69

60

52

47

40

35

34

32

31

22

27

21

iso-Prbpylbenzehe

280

< 1

< 1

< 1

< 1

< 1 '

<1

<1

< 1

< 1

< 1

<1

<1

< 1

n-Propyl benzene

NE

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

Tetrachloroethene

5

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

154

40

30

30

30

30

30

30

20

30

20

30

30

20

Toluene

1000

2

2

1

1

1

<1

<1

<1

<1

< 1

<1

<1

<1

1,1,1-Trichloroethane

200

<2

< 2

< 2

<2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,1,2-Trichloroethane

6

<2

<2

< 2

< 2

< 2

<2

<2 "

<2

<2

<2

<2

<2

<2

Trichloroethene

5

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,2,4-Trimethyl benzene

NE

< 1

< 1

< 1

< 1

< 1

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

Vinyl chloride

2

-15- ,

6 ,

«

6 ,

5

.4 ;

<2--

4

3

-4 •

' r?-..

' *

2. ¦'

Xylenes (Total)

10000

<2

3

3

2

2

2

1

<2

<2

1

<2

<2

<2

trans-1,2-Dichloroethene

100

<2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

Total VOCs



249

183

164

156

148

136

121

113

117

109

95

107

84































1,4-Dioxane

3

NT

NT

NT

NT

NT

NT

10 J

s:a '

5.6 ¦

5;3

1.7

; 4.7

318

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	' Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.

13 of 17

G:\40814\002\5YR Tables Figures\Table 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results ( M9/U





Bedrock Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

FW26D





6/21/2002

11/11/2002

5/30/2003

11/6/2003

5/19/2004

11/3/2004

5/3/2005

11/18/2005

6/18/2008

11/8/2006

6/14/2007

6/15/2008

11/6/2008

11/6/2008-Dup

Benzene

5

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

< 1

<1

<1

<1

Acetone

700

<10

<10

< 10

< 10

< 10

< 10

< 10

<10

< 10

< 10

< 10

<10

<10

<10

Chlorobenzene

NE

<2

<2

< 2

< 2

< 2

< 2

<2

<2

< 2

< 2

<2

<2

<2

<2

Chloroform

NE

<2 "

<2

< 2

< 2

< 2

< 2

< 2

<2

< 2

< 2

<2

<2

<2

<2

1,2-Oichlorobenzene

600

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

< 1

1,4-Oichloro benzene

76

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

< 1

1,1-Oichloroethane

81

<2

<2

< 2

< 2

< 2

< 2

<2

< 2

< 2

< 2

<2

<2

<2

<2

1,2-Oichloroethane

S

<2

<2

< 2

<2

< 2

. < 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

1,1-Oichloroethene

7

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

cis-1,2-Oichloroethene

70

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

Diethyl ether

NE

<5

<5

< 5

< 5

< 5

< 5

< 5

<5

< 5

< 5

<5

<5

<5

<5

Ethylbenzene

700

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

iso-Propyl benzene

280

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

n-Propyl benzene

NE

< 1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

Tetrachloroethene

5

<2

<2

< 2

<2

< 2

< 2

< 2

<2

< 2

< 2

<2

<2

<2

<2

Tetrahydrofuran (THF)

154

<10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

<10

<10

<10

<10

Toluene

1000

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

1,1,1 -Trichloroethane

200

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

1,1,2-Trichloroethane

6

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2 •

<2

Tiichloroethene

5

<2

<2

< 2

< 2

<2

< 2

< 2

< 2

< 2

< 2

. <2

<2

<2

<2

1,2,4-Trimethyt benzene

NE

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1 .

< 1

< 1

< 1

< 1

<1

< 1

Vinyl chloride

2

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

Xylenes (Total)

10000

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

trans-1,2-Dichtoroethene

100

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

Total VOCs



BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL





















1,4-Dioxane

3

NT

NT

NT

NT

NT

NT

NT

NT

NT

NT

NT

<1 R

<2

NT

Notes:

1.	All results are in micrograms per liter (pg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH,

INC.

14 of 17

G:\40814\002\5YR Tables FiguresMable 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results {pg/L)





Bedrock Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

FW28D - Page 2





6/20/2009

11/11/2009

6/12/2010

11/9/2010

6/24/2011

11/9/2011

6/9/2012

11/6/2012

6/6/2013

11/12/2013

4/2/2014

Benzene

5

<1

<1

< 1

< 1

<1

< 1

< 1

< 1

<1

< 1

< 1

Acetone

700

<10

<10

<10

<10

< 10

<10

<10

< 10

<10

<10

<10

Chlorobenzene

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Oichloro benzene

600

< 1

< 1

<1

<1

<1

< 1

< 1

<1

<1

<1

< 1

1,4-Oichloro benzene

75

<1

<1

<1

<1

<1

< 1

<1

< 1

< 1

<1

<1

1,1-Dichloroethane

81

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichloroethane

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Dichloroethene

7

<1

< 1

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

cis-1,2-Dichloroethene

70

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Diethyl ether

NE

<5

<5

<5

<5

<5

< 5

<5

<5

<5

<5

<5

Ethyl benzene

700

< 1

<1

< 1

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

iso-Propyl benzene

260

< 1

<1

< 1

<1

<1

<1

< 1

< 1

< 1

< 1

<1

n-Propyt benzene

NE

< 1

< 1

< 1

< 1

<1

< 1

<1

< 1

<1

< 1

<1

Tetrachloroethene

S

<2

<2

<2

<2

<2

• <2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

<10

<10

<10

<10

<10

<10

<10

<10

< 10

< 10

<10

Toluene

1000

< 1

<1

<1

. 
-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (iig/L)





Bedrock Groundwater

Detected Volatile Organic
Compounds

MCU
NHDES
AGQS

ERT04





5/17/2002

11/11/2002

5/30/2003

11/6/2003

6/18/2004

11/3/2004

6/3/2005

11/18/2005

5/18/2006

11/8/2006

5/15/2007

11/14/2007

5/15/2008

11/6/2008

5/20/2009

11/11/2009

Benzene

6

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

< 1"

< 1

< 1

Acetone

700

<10

<10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

< 10

<10

<10

<10

<10

< 10

<10

Chlorobenzene

NE

<2

<2

< 2

< 2

< 2

< 2

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

<2

< 2

< 2

< 2

< 2

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

1,2-Dichloro benzene

600

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

. < 1

< 1

<1

< 1

< 1

< 1

1,4-Dichlorobenzene

76

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

- < 1

<1

1,1 -Dichloroethane

81

<2

<2

< 2

< 2

< 2

< 2

<2

< 2

< 2

< 2 •

<2

<2

<2

<2

<2

<2

1,2-Oichloroethane

5

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

1,1-Oichloroethene

7

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1 •

- < 1

< 1

< 1

< 1

<1

< 1

< 1

< 1

cis-1,2-Dichloroethene

70

<2

<2

< 2

< 2

< 2

< 2

< 2

<2

< 2

< 2

<2

<2

<2

<2

<2

<2

Diethyl ether

NE

<5

<5

< 5

< 5

< 5

< 5

< 5

< 5

< 5

< 5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

<1

<1

< 1

< 1

< 1

< 1

<1

< 1

< 1

< 1

<1

< 1

<1

<1

<1

<1

iso-Propyl benzene

280

<1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

<1

n-Propyt benzene

NE

< 1

<1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

<1

<1

<1

<1

<1

Tetrachloroethene

6

<2

<2

< 2

< 2

<2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

<10

<10

< 10

< 10

< 10

< 10

<10

< 10

< 10

. < 10 '

<10

<10

<10-

<10

< 10

<10

Toluene

1000

<1

<1

< 1

< 1

< 1

< 1

1

< 1

<1

< 1

<1

< 1

< 1

< 1

< 1

< 1

1,1,1-Trichloroethane

200

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

1,1,2-Trichloroethane

5

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2-

<2

<2

Trichloroethene

5

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

1,2,4-Trimethyl benzene

NE

< 1

< 1

< 1

< 1

< 1

< 1

< 1

< 1

<1

< 1

<1

< 1

<1

<1

<1

<1

Vinyl chloride

2

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

<2

< 2

<2

<2

<2

<2

<2

<2

Xylenes (Total)

10000

<2

<2

<2

< 2

<2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Dichloroethene

100

<2

<2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

< 2

<2

<2

<2

<2

<2

<2

Total VOCs



BDL

BDL

BDL

BDL

BDL

BDL

1

. BDL

BDL

BDL

BDL

BDL

BDL

BOL

BDL

BDL

























1,4-Dioxane

3

NT

NT

NT

NT

z

H

NT

NT

NT

NT

NT

NT

NT

<1 R

<2

<2.1

<2

Notes:

1.	All resuitsare in micrograms per liter (yg/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe blinking Water Act.

5.	NE indicates that no MCL/AGQ5 Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected abova the laboratory detection limit.
9..R indicates that the result is rejected basedon data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to analysis

HALEY ALDRICH, INC.

16 of 17

G:\40814\002\5YR Tables FiguresVTable 6 - 2014-0728 Historical groundwater concentrations.pdf.xlsx

-------
Table 6

Detected Volatile Organic Compounds in Groundwater (2002-2014)

2014 Five-Year Review Report

Tinkham Garage Site, Londonderry, New Hampshire





Volatile Organic Compound Results (pg/L)





Bedrock Groundwater

Detected Volatile Organic
Compounds

MCL/
NHDES
AGQS

ERT04 - Page 2





5/12/2010

11/12/2010

5/27/2011

11/9/2011

5/9/2012

11/6/2012

5/6/2013

11/12/2013

4/2/2014

Benzene

S

<1

< 1

<1

<1

<1

<1

<1

<1

<1

Acetone

700

<10

<10

< 10

< 10

<10

< 10

< 10

<10

<10

Chlorobenzene

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

Chloroform

NE

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichlorobenzene

600

< 1

<1

<1

< 1

<1

<1

< 1

< 1

<1

1,4-Dichlorobenzene

75

<1

<1

< 1

< 1

<1

<1

< 1

<1

< 1

1,1-Oichloroethane

81

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2-Dichloroethane

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1-Oichloroethene

7

<1

<1

<1

<1

<1

<1

< 1

< 1

<1

cis-1,2-Dichloroethene

70

<2

<2

<2

<2

<2

<2

<2

<2

<2

Diethyl ether

NE

<5

< 5

<5

<5

<5

<5

<5

<5

<5

Ethyl benzene

700

<1

<1

<1

<1

<1

< 1

<1

<1

< 1

iso-Propyl benzene

280

<:1

< 1

<1

< 1

<1

< 1

<1

< 1

<1

n-Propyl benzene

NE

<1

<1

<1

<1

< 1

<1

<1

<1

<1

Tetrachloroethene

5

<2

<2

<2

<2

<2

<2

<2

<2

<2

Tetrahydrofuran (THF)

164

<10

<10

<10

<10

< 10

<10

<10

<10

<10

Toluene

1000

< 1

<1

< 1

<1

<1

< 1

<1

< 1

<1

1,1,1-Trichloroethane

200

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,1,2-Trichloroetharie

6

<2

<2

<2

<2

<2

<2

<2

<2

<2

Trichloroethene

6

<2

<2

<2

<2

<2

<2

<2

<2

<2

1,2,4-Trimethyl benzene

NE

<1

<1

<1

<1

< 1

<1

< 1

<1

<1

Vinyl chloride

2

<2

<2

<2

<2

<2

<2

<2

<2

<2

Xylenes (Total)

10000

<2

<2

<2

<2

<2

<2

<2

<2

<2

trans-1,2-Oichloroethene

100

<2

<2

<2

<2

<2

<2

<2

<2

<2

Total VOCs



BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL

BDL



















1,4-Dioxane

3

<2

<2

<2

<0.1 J

<0.1

< 0.2

. <0.1

<0

<0.1

Notes:

1.	All results are in micrograms per liter (mq/L).

2.	< indicates analyte not detected at a concentration above the specified laboratory reporting limit.

3.	AGQS indicates Ambient Groundwater Quality Standards established by the New Hampshire Groundwater Protection Rules (Env-Wq 402).

4.	MCL indicates Maximum Contaminant Concentration as established by the USEPA under the Safe Drinking Water Act.

5.	NE indicates that no MCL/AGQS Standard exists for that compound.

6.	Bold values indicate compounds that were detected above laboratory, minimum detection limits.

7.	Shaded values indicate compounds that were detected at concentrations greater that the MCL/AGQS.

8.	Total VOCs include all detected VOCs except 1,4-Dioxane. BDL indicates that no VOCs were detected above the laboratory detection limit.

9.	R indicates that the result is rejected based on data validation criteria.

10.	J indicates that the result is estimated based on data validation criteria.

11.	NT indicates not tested for this parameter.

12.	D indicates sample that was diluted prior to'analysis

HALEY ALDR1CH, INC.	17 of 17	G:\40814\002\5YRTablesFigures\Table6-2014-0728Historicalgroundwaterconcentrations.pdf.xlsx

-------
ni)'•©'¦ ¦ ;,X

-Ad'¦¦¦¦' '.T

I WOsM\

t"	' • \

v; \ \—.	>

_i	±	



§5

• QUADRANGLE LOCATION

!S
55

note

SITE LOCATION MAP TAKEN FROM PLAN TITLED "SITE LOCATION MAP"
DATED 18 DECEMBER 2012, FIGURE t. BY ROUX ASSOCIATES, INC

it at	cannons engineering • site technical committee

I u\Li . i est tinkham oarage site
ALDRlCH LONDONDERRY NEW HAMPSHIRE

SITE LOCATION MAP

sn
8j

s i

SOURCE:

USGS; Windham, New Hampshire
7.5 Minute Topographic Quadrangle

SCALE NONE
SEPTEMBER 2014

FIGURE 1

-------
LEQEW
NAIK2 M.

*w»*oxiMi«t-t tocAnoni or stream

APPWOWMUITE »CAlE in f«T

Yift-llv..,	ttwwaesrre

AI JlRrH lONOOIlOtMV HEM KAWPSMStE

SITE PLAN

FIGURE 2

-------
OVERBURDEN GROUNDWATER
TESTING RESULTS
APRIL 2014

FIGURE 3



osim.

FW2S^
I B I 0.5B I

iHOiCJkTTS TOTAL VOC» I 4-0K2*AMf
CO*»Ct*tWATiO»« I* vtf U&UKIRf 0 IK *£*«. JPI4

-------
MAI EYitr ewwowsewgeienwa wincMnokCfuiwnit
"«M" w*« SHI

ALLJKICH iC*MNM9«» mrrtHAM^sxAf

BEDROCK GROUNDWATER
TESTING RESULTS
APRIL 2014

wwemu	FIGURE 4

iWXATIS TQTM «Xl. 1 <

cowet*t*a«ows m u*» K£*am«o m aphu jou

ssass.

-------
APPENDIX C - Mann-Kendall Constituent Trend Analysis

-------
GSI MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation Dale:
Facility Name:
Conducted By:



Tlnkhama Garage
0.Miles

Sampling Point ID: [ Tetracmoroeltene | Trlchloroethene

J«blO:[40B14-002
Constituent. ; * -1
Concentration Units: '.in L

|j^-T.2-D)chtoroethen^ i|

JSX

Benzene

1.4-Dioxane

Sampling
Event

Sampling
Date

DVE-7 CONCENTRATION (ug/L)

l

21-May-0B

10

11

30



1

05



2

11-May-10

21

29

87



1





3

24-May-11

19

28

96









4

10-May-12

12

9

42









5

7-May-13

15

19

76









6

2-Apr-14

12

11

45



i





7

















8

















0

















10

















11

















12

















13

















14

















15

















16

















17

















18

















19

















20

















Coefficient of Variation:

0.29

0.50

0.43

0,00

0.00

0.00

0.99

Mann-Kendall Statistic (S):

-2

¦H

1

0

0

0

-9

Confidence Factor.

57.0%

70.3%

50.0%

39.3%

39.3%

39.3%

93.2%

Concentration Trend:

Stable

Stable

No Trend

Stable

Stable

Stable

Prob. Decreasing

100

O)
C

o

c

0)

o
c
o
(J

0.1

0.01



i"——









































\





12/08 07/09 01/10 08/10 02/11 0*11 04/12 10/12 05/13 11/13 06/14 12/14

Sampling Date

¦	¦ T etracMoroetn»n«
• T ncMofOethen®

¦	d*-1.2-OicM»oroew«rve
—— 1.2-D4CMofO»1f»«r»«

¦	Vinyl chtonck
¦ 8enz®rx>

—1.4-Ooxane

Notes:

t. At least (our independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples

2.	Confidence in Trend = Confidence (In percent) that constituent concentration is increasing (S>0) or decreasing (S<0) >95% * Increasing or Decreasing,
2 90% = Prohabfy Increasing or Probably Decreasing; < 90% and S>0 = No Trend < 90% SsO, and COV 2 1 = No Trend, < 90% and COV < 1 = Stable.

3.	Methodology based on "MAROS: A Decision Support System (or Optimizing Monitoring Plans". J J Aziz, M Ling, H S. Rtfai. C J Newell, and J R Gonzales,
Ground Wafer, 41(3):355-367,2003,

4.	Shaded cells Indicate a non detection: half the detection limit reported

DISCLAIMER: The GSI Mann-Kendall Toolkit is available 'as is" Considerable care has been exercised In preparing this software product however, no party, including without
limitation GSI Environmental tnc makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be table for any direct, indirect, consequential, incidental or other damages resulting from the use of this product or the information contained herein, Information in
this publication is subject to change without notice. GSI Environmental Inc.. disclaims any responsibility or obligation to update the information contained herein

GSI Environmental Inc., *ww gskiet com

-------
GSI MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation Date:!
Facility Name:
Conducted By.

18-JuM4

Tlnkhams Garage
O.MIIos

Job ID:[40814-002

Sampling Point ID:I Telrachtaroethene [ Tricxoroeihene T

Constituent: | FW11D
Concentration Unit*: ug'L

^t.ZDicniwoalfien^ t^teWoroetftBnMl

Vlnjrf

Benzene

1,4-Dwxan®

Sampling
Event

Sampling
Date

FW11D CONCENTRATION 

=*i

20-May-09



7

51

12

46

4

500

2

lO-Nov-09



6

23

6

23

2

210

3

10-May-1Q



27

30

5

15



230

4

9-Nov-10



17

22



S



110

5

24-May-ll



11

35

8

34



300

6

9-Nov-11



7

34

8

29

2

160

7

9-May-12



7

30

7

23

2

120

8

6-N0V-12



7

30

6

18

05

240

9

6-May-13



6

20

5

13

1

270

10

12-Nov-13



4

26

8

27

2

480

11

3-Ap»-14

1

4

25

5

19

1

240

12

















13

















14

















15

















16

















17

















18

















19

















20

















Coefficient of Variation:

0.00

0.7*

0.29

0.45

0 46

0.66

0.49

Mann-Kendall Statistic (S):

0

-29

-18

-6

-12

-9

6

Confidence Factor:

45.1%

98.7%

90.5%

66.8%

79.9%

72.9%

64.8%

Concentration Trend:

Stable

Decreasing

Prob. Decreasing

Stable

Stable

Stable

No Trend

1000

O)

c
o

'•M
«
l-

c
o
u
c

o
o

100

10

1 •

0.1



» T«trtcworo«tn«n«
-Tncntofcmftene

-	as-1 2-Oiciiion>em®rm
-l.2DtcMor0) or decreasing (S<0) >95% = increasing or Decreasing,
2 90% - Probably Increasing or Probably Decreasing < 90% and S>0 = No Trend: < 90%. SSO, and COV i 1 = No Trend; < 90% and COV < 1 = Stable.
Methodology based on "MARQS: A Decision Support System for Optimizing Monitoring Plans", J J Aziz, M Ling, H S Rifai, C.J. Newell, and J R. Gonzales
Groundwater. 41(3) 355-367. 2003

Shaded cells indicate a non detection halt the detection limit reported

DISCLAIMER: The GSI Mann-Kendall Toolkit is available "as is" Considerable care has been exercised in preparing Bus software product: however, no party, including without
limitation GSI Environmental Inc., makes any representation or warranty regarding the accuracy, correctness, or completeness ot the Information contained herein and no such
party shall be fable for any direct, indirect, consequential incidental or other damages resulting from the use of this product or the information contained herein Information in
this pubtcabon is sub/eel to change without notice GSI Environmental Inc., disclaims any responsibly or obtgation to update the information contained herein
	GSI Enwvivmntal Inc, IWWUgSl-nefCOW	

-------
GSI MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation Date:
Facility Name:
Conducted By:

18-Jul-14

Ttnkhams Garage

O.Miles

Job ID: 40814-002
Constituent:

Concentration Units:

FW20



T ©tracNof oethene

Sampling
Event

Sampling
Date

FW20 CONCENTRATION (ug/L)

1

21-May-09



4

46

12

26

3

ISO

2

1O-NOV-09

1

3

34

10

25

3

62

3

1O-May-10



4

51

17

42

4

120

4

12-Nov-10

1

3

31

12

25

7

71

5

24-Msy-11



3

37

to

23

2

96

6

9-Nov-11



t

29

S

20

2

38

7

9-May-12

1



32

10

16

2

32

8

6-NOV-12



2

23

to

22

5

61

9

6-May-13



3

32

10

19

3

130

10

12-Nov-13





11

6

17

3

75

11

3-Apr-14

1

3

40

11

16

2

100

12

















13

















14

















15

















te

















17

















18

















19

















20

















Coefficient of Variation:

0.00

0.37

0.32

0.25

0.31

0 48

0.42

Mann-Kendall Statistic (S);

0

-22

-20

-18

-38

9

-3

Confidence Factor

45,1%

94.9%

92.9%

90.5%

99.9%

72.9%

56.0%

Concentration Trend:

Stable

Prob. Decreasing Prob. Decreasing; Prob. Decreasing

Decreasing

Stable

Stable

D)
C

.2
•*—

t.
c

0)

u
c
o
o

1000

100

» T »tr»chtoro«jn«K»
» TrtcMoro«th«fv»
¦ civ 1.2-OichiormKhVfM
• 1.2-OtcMoro«than«
•Vlrvyt chtond*
-B«n*ene
-1 4-Dtoxan*

12/08 07/09 01/10 0S/10 02/11 09/11 04/12 10/12 05/13 11/13 06/14 12/14

Sampling Date

Notes:

1.	At least tour independent sampling events per well are required tor calculating Itie trend Methodology is valid for 4 to 40 samples

2.	Confidence In Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0) >95% = Increasing or Decreasing.
t 90% = Probably Increasing or Probably Decreasing, < 90% and S>0 = No Trend; < 90%, SsO, and COV 2 1 = No Trend; < 90% and COV < 1 = Stable,

3.	Methodology based on "MAROS A Decision Support System for Optimizing Monitoring Plans". J J Aziz, M Lmg. H S. Rifai, C J Newell, and J R. Gonzales,

Ground Water, 41 (3) 355-367, 2003.

4.	Shaded cells indicate a non detection, half the detection limit reported

DISCLAIMER: The GSI Mann-Kendall Toolkit is available "as is'. Considerable care has been exercised in preparing this software product, however, no party, including without
limitation GSI Environmental Inc. makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be liable tor any direct, indirect, consequential, incidental or other damages resetting from the use ot this product or the information contained herein information in
this publication is subject to change without notice. GSI Environmental tnc,. disclaims any responsibility or obligation to update the information contained herein,
	GSI Emironivental inc. wnwgsi-nelcsmi	

-------
GSi MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation D»tr h S-Jul-14

Facility Name;
Conducted By:

Tlnkhams Garaga

0,Miles

1

Job (fc|40814-002
Wuent: nai x
i Units: uij.i

ConsWuenfcfNA^F
Concentration I

Sampling Point Idsl Teuachtoroethere [ rnciHorogtharM 1 i	1 2Dch*oe | Vfriyt cJHornte |

Banzana

i 4-0o»3no

Sampling
Event

Sampling
Date

NAI-K2 CONCENTRATION (ugfl.)

1

19-May-OB

47

230

220

1

7

¦



2

H-Nov-09

32

180

230



9





3

11-May-10

67

240

550

2.5

20

25



4

12-Nov-10

11

42

120









5

25-May-11

49

140

520

25

3





e

9-Nov-11

30

92

370





25



7

9-May-12

21

40

190



7



0 05

6

6-NOV-12

26

49

220



10



066

9

6-May-13

31

71

260



7



045

10

12-Nov-13

37

88

270



20



082

11

4-Apr-l4

.

54

190



7

05

005

12

















13

















14

















15

















16

















17

















18

















19

















20

















Coefficient of Variation:

0.46

0.67

0.48

0.49

0.63

0 88

0.61

Mann-Kendall Statistic (S):

•13

-23

-S

-4

9

-15

-28

Confidence Factor:

82.1%

95.7%

61.9%

59.0%

72.9%

85.9%

98.4%

Concentration Trend:

Stable

Decreasing

Stable

Stable

No Trend

Stable

Decreasing

en

3

C

O

c

0)

a
c
o
o

1000

m

10

0.01



















































































































»T«tracnfcyoem®r»

-	TncMofoetlw*
-o»-1 2-OJChkxo«m«ri»

¦ tJ24

•Vrtyi chloride

-	B«n/«rw>

-	1.4-Dtoican*

12/08 07/09 01/10 0S/10 02/11 09/11 04/12 10/12 05/13 11/13 06/14 12/14

Sampling Date

Notes:

1.	At least tour independent sampling events per well are required for calculating the trend Methodology is valid for 4 to 40 samples

2.	Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% - increasing or Decreasing;
i 90% = Probably Increasing or Probably Decreasing: < 90% and S>0 = No Trend; < 90%, SS0. and COV i 1 = No Trend. < 90% and COV < 1 = Stable.

3.	Methodology based on "MAROS; A Decision Support System for Optimizing Monitoring Plans". J.J. Aziz, M. Ling, H S Rifal. C.J Newell, and J R. Gonzales,

Ground Water, 4t{3):355-367. 2003,

4.	Shaded cells indicate a non detection; half the detection limit reported

DISCLAIMER: The GSI Mann-Kendall Toolkit is available "as is' Considerable care has been exercised in preparing this software product. however. no party, including without
limitation GSI Environmental Inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be liable for any direct. Indirect, consequential, incidental or other damages resulting from the use of this product or the information contained herein. Information in
this publication is subject to change without notice. GSI Environmental Inc.. disclaims any responsibility or obligation (o update the information contained herein
	GSI Enmroemeetal Inc. 1ww.9sj-nef.com	

-------
Sampling Point [Q:| Tetra

Moraethene TiieMoro«hene

fca-i.2-PitfS

1 20cHcrpa(h»ni

Vinyl chloride

Beftfer

1.4-Dioxane

Sampling
Event

Sampling
Date

NAI-M1 CONCENTRATION (ug/L)

1

14-May-0a

3

48

31









2

16-M«y-09

1

10

23









3

10-May-10



13

19









4

25-May-11



7

12



i





5

9-M3V-12



21

56









6

B-May-13



3

2



i



012

7

4-ApM4



S

3



»



055

B

















9

















ID

















11

















12

















13

















14

















15

















16

















17

















18

















19

















2

















Coefficient of Variation:

o.ss

1,02

0.90

0.00

0.59

0.00

0.43

Mann-Kendall Statistic (S):

-6

-11

-11

0

2

0

¦¦¦

Confidence Factor:

76.4%

93.2%

93.2%

37.9%

55.7%

37.9%

88.1%

Concentration Trend:

Stable

Prob. Decreasing Prob. Decreasing

Stable

No Trend

Stable

Stable

100

c
o

c
o
o
£
o
o

to

f

0.1

»T0tr>cM£>*Q«tft*rte

-	Ctt-1 „2-DiCMoro«tMrw
» V2-DcftlOfi»th*nc
-V«yf cftlorid®

-	Benzene
¦1J

10/06	02/09	07/09	11/10	04/12

Sampling Date

08/13

12/14

Notes:

1. At least four independent sampling events per well are required for calculating the trend Methodology is valid for 4 to 40 samples

Confidence In Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing;
2 90% = Probably Increasing or Probably Decreasing, < 90% and S>0 = No Trend: < 90%, Sso. and COV £ 1 = No Trend; < 90% and GOV < 1 = Stable.

3.	Methodology based on "MAROS A Decision Support System for Optimizing Monitoring Plans". J.J Aziz, M Ling, H.S Rtfai. C.J Newell, and J.R Gonzales,
Ground Water 41(3>:355-367, 2003

4.	Shaded cells indicate a non detection; half the detection limit reported

DISCLAIMER; The GSI Mann-Kendall Toolkit is available 'as is'. Considerable care has been exercised in preparing ihis software product, however, no party, including without
limitation GSI Envmimntel Inc.. makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be liable for any direct, indirect, consequential, incidental or other damages resulting from the use of this product or the information contained herein Information in
this publication is subject to change without notice. GSI Environmental Inc. disclaims any responsibility or obbg&ion to update the information contained herein

GSI Enwonmertal Inc. wwwgsi-netccm

-------
GSI MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation Date:

ta-Jui-14







Job 10:

40814-002

Facility Name:

Tinkhams Garage



Constituent:

~

5

o

Conducted By:

O.Miles

Concentration Units:

ug/L





Sampling Point ID:| TelraeNoroalhene

TncHoroethene

=S-1.2-Dichloroethet^ t .2-OtehkJtoe«ane | Vtnyt chloride

Benzene



Sampling
Event

Sampling
Date





OW2D CONCENTRATION (ug/L)





1

21 -May-09

*3

15

170

19

9

0 5

190

2

10-NOV-Q9



11

120

15

7



170

3

IO-May-10

e

14

130

19

9

Of

110

4

S-Nov-10

3

9

100

16

6



100

5

2S-May-11

3

8

86

11

5

0,5

90

6

9-Nov-11

3

7

82



5

05

46

7

10-May-12

3

8

80

12

4

05

32

8

6-Ncv-12



6

76

12

4



74

9

6-May-13



5

47

9

2



80

to

52-NOV-13



6

72

13

5



120

11

3-Apr-14



4

46

7

3

05

45

12

















13

















14

















15

















16

















17

















16

















19

















20

















Coefficient of Variation:

0.64

0,42

0.40

0.29

0.42

0.34

0.52

Mann-Kendall Statistic (S):

-40

¦47

-51

-31

-40

-12

-29

Confidence Factor:

100.0%

>99.9%

>99.9%

99.2%

100.0%

79.9%

98.7%

Concentration Trend:

Decreasing

Decreasing

Decreasing

Decreasing

Decreasing

Stable

Decreasing

1000

0. 100

3

.2 10

o
o
c
o
o

0.1



¦ Tatrsctitoroflffwne
-TncfUoroetrver*
- as-1.2-OfcftkXMtharw
-1,2-DicH4«oath«oo
-Vinyl cfiioria®
-B«ruen«

-1,4-DiO*ftrv*

12/08 07/09 01/10 0&/10 02/11 09/11 0*12 10/12 05/13 1V13 06/14 12/14

Sampling Date

Notes;

1.	At least four independent sampling events per well are required for calculating the trend. Methodology is valid for 4 to 40 samples

2.	Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing;
2 90% = Probably Increasing or Probably Decreasing, < 90% and S>0 = No Trend. < 90%. SSO. and COV a 1 = No Trend, < 90% and COV < 1 ¦ Stable.
Methodology based on "MAROS: A Decision Support System for Optimizing Monitoring Plans". J.J, Aziz, M. Ling, H S Rifai, C,J Newell, and J R. Gonzales,

Ground Water, 41(3):355-367, 2003

Shaded ceils indicate a non detection: half the detection limit reported

DISCLAIMER: The GSI Mann-KBndall Toolkit is available 'as is". Considerable care has been exercised in preparing this software product: however, no party, including without
limitation GSI Environmental Inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be Sable for any direct, indirect consequential, incidental or other damages resulting from the use of this product or the information contained herein. Information in
this publication is sutyect to change without notice GSI Environmental Inc.. disclaims any responsibility or obligation to update the information contained herein,
	GSI Emkonmental Inc.. w»r.j|8Mwtcoffl		

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GSI MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation Date:





Job ID:

40814-602

Facility Name

Tinkhams Garage



Constituent:

LGSW

Conducted By:

O,Miles

Concentration Units:

ufl/L

L























r n 1 4 in



Trertoroeftene fci»-t.2-DicMixoeih#n^ t.Z-DcWoroethane | Vlnytchloride

Benzene

1.4-Dtamne

sampling roini iu;



Sampling
Event

Sampling
Date

LGSW CONCENTRATION (ug/t)

1

20-May-09

1







1

8

43

2

11-May-tO









3

j

42

3

25-May-11









4

7

37

4

IO-May-12





1



2

6

13

5

7-May-13





1



2

8

35

e

31-Mar-14

1

1

1

05

2

7

30

7

















8

















9

















10

















tt

















12

















13

















14

















15

















16

















17

















18

















19

















20

















Coefficient of Variation:

0.00

0 00

0.00

0.00

0.44

0.11

0.33

Mann-Kendall Statistic (S):

0

0

0

0

0

-3

-11

Confidence Factor

39.3%

39.3%

39.3%

39.3%

39.3%

64.0%

97.2%

Concentration Trend:

Stable

Stable

Stable

Stable

Stable

Stable

Decreasing

100

mmm

Ol
3

C

O

c

0)
o
c
o
O

10

1

0.1



T®tr»chtofO«W«o« 20
LGSW

CONCENTRATION
(ugt)

- ds-1 2-Dichloroethone



12/08 07/09 01/10 08/10 02/11 0W11 04/12 10/12 05/13 11/13 OS/14 12/14

Sampling Date

Notes:

At least four independent sampling events per well are required for calculating the trend Methodology is valid lor 4 to 40 samples
2, Confidence in Trend = Confidence (in percent) that constituent concentration is increasing (S>0) or decreasing (S<0): >95% = Increasing or Decreasing,
a 90% = Probably Increasing or Probably Decreasing; < 90% and S>0 = No Trend, < 80%, SsO, and GOV 2 1 = No Trend, < 90% and COV < 1 ¦ Stable.
Methodology based on "MAROS A Decision Support System for Optimizing Monitoring Plans*. J J Aziz, M Ling, H s Rifai. C J Newell, and J R. Gonzales.
Ground Wafer, 41(3) 355-367, 2003.

4. Shaded cells Indicate a non detection, nail the detection limit reported

0/SCLA/MER: The GSI Mann-Kendall Toolkit is avalaWe "as is" Considerable care has been exercised in prepanng this software product: however, no paly, including without
limitation GSI Environmental Inc . makes any representation or warranty regarding the accuracy, correctness, or completeness of tlw information contained herein, and no such
party shall be liable for any direct, indirect, consequential, incidental or other damages resulting from the use of this producf or the information contained herein. Information in
this publication is subject to change without notice GSI Environmental Inc, disclaims any responsibility or obligation to update the information contained herein

GSI Environmental Inc., www, gsi-net com

-------
GSI MANN-KENDALL TOOLKIT

for Constituent Trend Analysis

Evaluation Date:
Facility Name:
Conducted By;

18-Jul-14
Tinkhams Garage

O.Miles

Sampling Point ID:[Taft^too^Sie|TtMilon»lhene

	

.. 1 2-[>chkjroe

Job ID: 40814-002
Constituent: FW21D
Concentration Units:! »g,'i

9

Vinyl

cWOfido

Benzene

|^i4-Dio««ne I

Sampling
Event

Sampling
Date

FW21D CONCENTRATION (ug/L)

1

21-May-OS





15

20

4

3

58

2

11-May-10





13

18

3

3

56

3

25-May-11





14

19

4

3

53

4

10-May-12





11

14

2

3

1 7

5

7-May-13





13

16

2

3

47

6

31-Mar-14





11

13

2

3

38

7

















e

















9

















10

















11

















12

















13

















14

















15

















16

















17

















18

















1&

















20

















Coefficient of Variation:

0.00

0.00

0.12

0.19

0.35

0,00

0.34

Mann-Kendall Statistic (S):

0

0

-9

-11

-9

0

-11

Confidence Factor

39 3%

393%

93.2%

100.0%

93.2%

39,3%

97.2%

Concentration Trend:

Stable

Stable

Prob. Decreasing

Decreasing

Prob Decreasing

Stable

Decreasing

S)
3

C
O

c

ID

u
c
O
Q

-	T •ftacftforo«ff»(W 20
FW21D

CONCENTRATION
(ug/L)

-	T ncftkx ostoene

» cis-1,2-Ochk>rooth®n®

m$ 07/09 01/10 08/10 02/11 09/11 04/12 10/12 05/13 11/13 06/14 IZ'U

Sampling Date

Notes:

1.	At least (bur Independent sampling events per well are required for calculating ttie trend Methodology is valid for 4 to 40 samples

2.	Confidence in Tfend - Confidence {in percent) that constituent concentration is increasing (S>0) or decreasing (S<0) >95% = Increasing or Decreasing;
a 90% = Probably increasing or Probably Decreasing <¦ 90% and S>0 = No Trend. < 90%, Sso. and COV i 1 = No Trend, < 90% and COV < 1 = Stable,
Methodology based on "MAROS: A Decision Support System for Optinuzing Monitonng Plans", J.J Aziz, M Ling, H,S. Rifai, C J Newell, and J R Gonzales.
Groundwater 41(3)355-367,2003

4. Shaded cells indicate a non detection , half the detection limit reported

DISCLAIMER: The GSI Mann-Kendall Toolkit is available "as is' Considerable care has been exerased in preparing this software product, however, no party, including without
limitation GSI Environmental Inc., makes any representation or warranty regarding the accuracy, correctness, or completeness of the information contained herein, and no such
party shall be Jabte for any direct, indirect, consequential, incidental or other damages resulting from the use of this product or the information contained herein. Information m
this publication is subject to change without notice. GSI Environmental Inc.. disclaims any responsibility or obligation to update the information contained herein.

GSI Envmmnoi Inc.. wm.gsi-net.cotn

-------