EPA 542-R-l 1-011
August 2012
United States Office of Solid Waste and Emergency Response
Environmental Protection ,, ,, ,, , Jr ... .
Agency Office of Superfund Remediation and
Technology Innovation
Optimization Review
Sidney and Richardson Hill Road Landfills
Delaware County, New York
www.epa.gov/superfund/remedytech | www.clu-in.org/optimization | www.epa.gov/superfund/cleanup/postconstruction
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OPTIMIZATION EVALUATION
SIDNEY AND RICHARDSON HILL ROAD LANDFILLS
DELAWARE COUNTY, NEW YORK
Report of the Optimization Evaluation
Site Visit Conducted at the Sidney and Richardson Hill Road Landfill Superfund Sites
August 23, 2011
Final Report
April 4, 2012
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EXECUTIVE SUMMARY
Optimization Background
For more than a decade, the U.S. Environmental Protection Agency (EPA) Office of Superfund
Remediation and Technology Innovation (OSRTI) has provided technical support to EPA Regional
offices through third-party optimization evaluations. OSRTI has conducted more than 100 optimization
studies at Superfund sites nationwide via Independent Design, Remediation System Evaluation (RSE),
and Long-Term Monitoring Optimization (LTMO) reviews.
OSRTI is now implementing its National Strategy to Expand Superfund Optimization from Remedial
Investigation to Site Completion. The strategy unifies previously independent optimization efforts (RSE,
LTMO, Triad Approach, and Green Remediation) under the single activity and term "optimization,"
which can be applied at any stage of the Superfund project life cycle. EPA's working definition of
optimization as of June 2011 is as follows:
"A systematic site review by a team of independent technical experts, at any phase of a
cleanup process, to identify opportunities to improve remedy protectiveness,
effectiveness, and cost efficiency, and to facilitate progress toward site completion. "
An optimization review at the remedy stage therefore considers the goals of the remedy, available site
data, the conceptual site model (CSM), remedy performance, protectiveness, cost-effectiveness, and
closure strategy. A strong interest in sustainability has also developed in the private sector and within
federal, state, and municipal governments. Consistent with this interest, optimization now routinely
considers environmental footprint reduction during optimization reviews. An optimization review
includes reviewing site documents, interviewing site stakeholders, potentially visiting the site for one day,
and compiling a report that includes recommendations in the following categories:
Protectiveness
Cost-effectiveness
Technical improvement
Site closure
Environmental footprint reduction
The recommendations are intended to help the site team identify opportunities for improvements in these
areas. In many cases, further analysis of a recommendation, beyond that provided in this report, may be
needed before the recommendation can be implemented. Note that the recommendations are based on an
independent evaluation and represent the opinions of the evaluation team. These recommendations do not
constitute requirements for future action, but rather are provided for consideration by the Region and
other site stakeholders.
Site-Specific Background
The Sidney Landfill site is located on Richardson Hill Road approximately 10 miles southeast of Sidney,
New York. In March 1989, the site was added to the National Priorities List (NPL) based on
investigations completed by the New York State Department of Environmental Conservation (NYSDEC)
and the New York State Department of Health (NYSDOH). The Richardson Hill Road Landfill (RHRL)
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site, which is also on the NPL, is located immediately south of the Sidney Landfill site. Historical waste
disposal resulted in polychlorinated biphenyl (PCB) and volatile organic compound (VOC) contamination
of soil and groundwater at the Sidney Landfill site and of soil, groundwater, and sediments at the RHRL
site. Soil and sediment remedies have been implemented and completed at both sites. Groundwater
remediation with a pump and treat system is ongoing at the RHRL, and pumping from the North Area of
the RHRL site is included in the groundwater remedy for Sidney Landfill site. The respondents at the two
sites are Amphenol Corporation and Honeywell, Inc., which is the successor to Bendix Corporation and
Allied Signal, Inc.
Summary of Conceptual Site Model (CSM)
Groundwater contamination at both sites is present in the overburden and bedrock. The soil remedies have
likely reduced the potential for additional contamination from soil. However, groundwater concentrations
at the Sidney Landfill remain relatively stable, or potentially increasing (for example, at MW-6D), since
the soil remedy was completed. The Sidney Landfill is located on a groundwater flow divide, and
groundwater flow and groundwater contamination to the north are not well understood. Seeps at the
bottom of the hill to the north are impacted with chlorinated volatile organic compound (CVOC)
contamination above standards, suggesting that at least part of the plume is migrating to the north. The
North Area recovery system that is part of the RHRL site may address contamination that migrates to the
west or south from the Sidney Landfill site. However, the hydraulic gradient in the northern portion of the
North Area recovery system trends away from Sidney Landfill, and the hydraulic gradient at the southern
end trends from RW-4 to the south. This observed pattern suggests that the wells do not provide capture
of contamination migrating from the Sidney Landfill in the direction of these wells.
For the RHRL site, no groundwater quality data are available from beneath the landfills since the landfill
cap was constructed or up gradient of the extraction trench. It is therefore difficult to determine the effect
the RHRL site soil remedy has had on groundwater quality. Contaminant concentrations in groundwater
downgradient of the RHRL extraction trench are generally decreasing; with the exception of samples
from well TMW-02. These concentration decreases are likely the result of operating the groundwater
extraction trench. Hydraulic data are insufficient to confirm capture, and it is too early to determine from
groundwater sampling if capture is sufficient to allow downgradient concentrations to decrease to cleanup
standards. Gaps in capture, if present, would likely be around the northern end of the trench, through
shallow bedrock under the trench, and or through deeper bedrock, given that the contamination in the
shallow bedrock beneath the trench does not appear to have been vertically delineated. No recent water
quality data are available from the RHRL North Area to evaluate water quality trends in that area.
Summary of Findings
Groundwater flow and contaminant migration pathways at the Sidney Landfill site do not appear
to be well understood, especially to the north.
Insufficient information is available to evaluate plume capture in both areas of pumping.
Contaminant concentrations at the Sidney Landfill have decreased since the Remedial
Investigation (RI) but have not continued to decrease since implementation of the groundwater
remedy at the RHRL North Area. Concentrations may be increasing in some localized areas at the
Sidney Landfill site.
Contamination downgradient of the RHRL extraction trench was likely present before the remedy
was in place and is likely contributing to limited recontamination of the sediments at South Pond.
Decreasing contaminant concentrations in locations downgradient of the trench suggest some
degree of plume capture, but insufficient information is available to determine if capture is
complete.
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The 2008 fish tissue sampling results raise the concern about ongoing exposure offish to
significant levels of PCBs. The 2010 surface water and sediment sampling indicated some
recontamination of the South Pond sediments by PCBs and undetectable PCBs in surface water.
The 2011 fish sampling may help evaluate whether conditions are improving.
The groundwater treatment plant is well maintained and routinely meets compliance standards.
Summary of Recommendations
Recommendations are provided to improve remedy effectiveness, reduce cost, and provide technical
improvement. The recommendations in these areas are as follows:
Improving effectiveness - conduct comprehensive water level measurement events and additional
groundwater sampling to better understand contaminant transport at the Sidney Landfill site, update the
groundwater flow model for use in evaluating plume capture, and potentially evaluate the discharge of
PCBs to South Pond.
Reducing cost - consider potential reductions in operator labor, use of passive diffusion bags (PDB) for
groundwater sampling of VOCs, discontinuation of laboratory analysis for natural attenuation parameters,
and use of greens and filtration for metals removal.
Technical improvement - track leachate levels and leachate quality in the on-site toxic substances waste
unit, and improve operation of extraction and treatment plant flow meters.
No considerations were identified at this time for accelerating site closure, and no opportunities were
identified at this time for meaningful reduction of the remedy environmental footprint.
in
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NOTICE
Work described herein was performed by Tetra Tech GEO (TtGEO) for the U.S. Environmental
Protection Agency (EPA). Work conducted by TtGEO, including preparation of this report, was
performed under Work Assignment #58 of EPA contract EP-W-07-078 with Tetra Tech EM Inc.,
Chicago, Illinois. Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
IV
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PREFACE
This report was prepared as part of a national strategy to expand Superfund optimization from remedial
investigation to site completion implemented by the U.S. Environmental Protection Agency (EPA) Office
of Superfund Remediation and Technology Innovation (OSRTI). The project contacts are as follows:
Organization
Key Contact
Contact Information
U.S. EPA Office of Superfund
Remediation and Technology
Innovation
(OSRTI)
Kathy Yager
EPA
Technology Innovation and Field Services
Division
11 Technology Drive (ECA/OEME)
North Chelmsford, MA 01863
yager.kathleen@epa.gov
phone:617-918-8362
Tetra Tech EM Inc.
(Contractor to EPA)
Jody Edwards, PG
Tetra Tech EM Inc.
1881 Campus Commons Drive, Suite 200
Reston,VA20191
jody.edwards@tetratech.com
phone: 802-288-9485
Tetra Tech GEO
(Contractor to Tetra Tech EM Inc.)
Doug Sutton, PhD,
PE
Tetra Tech GEO
2 Paragon Way
Freehold, NJ 07728
doug.sutton@tetratech.com
phone: 732-409-0344
v
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LIST OF ACRONYMS
AMSL
AOC
bgs
cfm
coc
CSM
CVOC
DCA
DCE
DI
EPA
BSD
GAC
gpd
gpm
GWTP
HOPE
HRC
1C
LNAPL
LTMO
mg/kg
mg/L
MNA
NPL
NYCRR
NYSDEC
NYSDOH
O&M
ORP
OSRTI
P&T
PAC
PAH
PCB
PDBs
PISCES
PPM
Micrograms Per Kilogram
Micrograms Per Liter
Above Mean Sea Level
Administrative Order on Consent
Below Ground Surface
Cubic Feet Per Minute
Constituent of Concern
Conceptual Site Model
Chlorinated Volatile Organic Compound
Dichloroethane
Dichloroethene
Deionized
United States Environmental Protection Agency
Explanation of Significant Differences
Granular Activated Carbon
Gallons Per Day
Gallons Per Minute
Groundwater Treatment Plant
High Density Polyethylene
Hydrogen Release Compound
Institutional Control
Light Non-Aqueous Phase Liquids
Long-Term Monitoring Optimization
Milligrams Per Kilogram
Milligrams Per Liter
Monitored Natural Attenuation
National Priorities List
New York Codes, Rules and Regulations
New York State Department of Environmental Conservation
New York State Department of Health
Operations and Maintenance
Oxidation Reduction Potential
Office of Superfund Remediation and Technology Innovation
Pump and Treat
Polyaluminum Chloride
Polynuclear Aromatic Hydrocarbons
Polychlorinated Biphenyl
Passive Diffusion Bags
Passive In Situ Concentration-Extraction Samplers
Parts Per Million
VI
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PRP Potential Responsible Party
PSI Pounds Per Square Inch
PVC Polyvinyl Casing
QAPP Quality Assurance Project Plan
RAO Remedial Action Objective
RCRA Resources Conservation and Recovery Act
RD Remedial Design
RHRL Richardson Hill Road Landfill
RI Remedial Investigation
RI/FS Remedial Investigation and Feasibility Study
ROD Record of Decision
RSE Remedial System Evaluation
RTU Reaction Treatment Unit
SPDES State Pollutant Discharge Elimination System
SVOCs Semi-Volatile Organic Compound
TCA Trichloroethane
TCE Trichloroethene
TSCA Toxic Substances Control Act
VC Vinyl Chloride
VI Vapor Intrusion
VOC Volatile Organic Compound
vn
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TABLE OF CONTENTS
EXECUTIVE SUMMARY i
NOTICE iv
PREFACE v
LIST OF ACRONYMS vi
TABLE OF CONTENTS viii
1.0 INTRODUCTION 1
1.1 PURPOSE 1
1.2 TEAM COMPOSITION 2
1.3 DOCUMENTS REVIEWED 2
1.4 QUALITY ASSURANCE 4
1.5 PERSONS CONTACTED 4
2.0 SITE BACKGROUND 5
2.1 LOCATION 5
2.2 SITE HISTORY 5
2.2.1 HISTORICAL LAND USE AND FACILITY OPERATIONS 5
2.2.2 CHRONOLOGY OF ENFORCEMENT AND REMEDIAL ACTIVITIES 5
2.3 POTENTIAL HUMAN AND ECOLOGICAL RECEPTORS 7
2.4 EXISTING DATA AND INFORMATION 8
2.4.1 SOURCES OF CONTAMINATION 8
2.4.2 GEOLOGY SETTING AND HYDROGEOLOGY 9
2.4.3 SOIL CONTAMINATION 10
2.4.4 SOIL VAPOR CONTAMINATION 11
2.4.5 GROUNDWATER CONTAMINATION 11
2.4.6 SURFACE WATER AND SEDIMENT CONTAMINATION 12
2.4.7 FISH TISSUE CONTAMINATION 13
3.0 DESCRIPTION OF PLANNED OR EXISTING REMEDIES 14
3.1 REMEDY AND REMEDY COMPONENTS 14
3.1.1 EXTRACTION TRENCH 15
3.1.2 NORTH AREA RECOVERY SYSTEM 16
3.1.3 TREATMENT PLANT 16
3.2 REMEDIAL ACTION OBJECTIVES AND STANDARDS 17
3.2.1 REMEDIAL ACTION OBJECTIVES 17
3.2.2 CLEANUP STANDARDS 17
3.2.3 TREATMENT PLANT OPERATION STANDARDS 18
3.3 PERFORMANCE MONITORING PROGRAMS 18
4.0 CONCEPTUAL SITE MODEL (CSM) 20
4.1 CSM OVERVIEW 20
4.2 DATA GAPS 21
4.3 IMPLICATIONS FOR REMEDIAL STRATEGY 21
Vlll
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5.0 FINDINGS 22
5.1 SUBSURFACE PERFORMANCE AND RESPONSE 22
5.1.1 GROUND WATER FLOW AND PLUME CAPTURE 22
5.1.2 GROUNDWATER CONTAMINANT CONCENTRATIONS 24
5.1.3 SURFACE WATER AND SEDIMENT CONTAMINATION 25
5.1.4 FISH TISSUE CONTAMINATION 25
5.2 COMPONENT PERFORMANCE 26
5.2.1 EXTRACTION NETWORK 26
5.2.2 GROUNDWATER TREATMENT PLANT 26
5.3 REGULATORY COMPLIANCE 27
5.4 COMPONENTS OR PROCESSES THAT ACCOUNT FOR MAJORITY OF ANNUAL COSTS 27
5.5 APPROXIMATE ENVIRONMENTAL FOOTPRINTS ASSOCIATED WITH REMEDY 27
5.6 SAFETY RECORD 28
6.0 RECOMMENDATIONS 29
6.1 RECOMMENDATIONS TO IMPROVE EFFECTIVENESS 29
6.1.1 DELINEATE CONTAMINANT MIGRATION PATHWAYS 29
6.1.2 UPDATE GROUND WATER FLOW MODEL AND EVALUATE CAPTURE 30
6.1.3 POTENTIALLY EVALUATE PCB SEDIMENT CONTAMINATION IN SOUTH POND ..30
6.1.4 REPORTING NORTH AREA WATER LEVELS 32
6.1.5 MONITOR INSTITUTIONAL CONTROLS 32
6.1.6 MONITOR EXTRACTION TRENCH FOR POTENTIAL FOULING 32
6.2 RECOMMENDATIONS TO REDUCE COSTS 32
6.2.1 EVALUATE POTENTIAL FOR REDUCING OPERATOR LABOR 32
6.2.2 CONSIDER USING PDBs FOR VOC SAMPLING 33
6.2.3 ELIMINATE LABORATORY ANALYSIS FORNATURAL ATTENUATION 33
6.2.4 CONSIDER POTENTIAL MODIFICATIONS TO THE GWTP TO HELP REDUCE LABOR
COSTS 33
6.3 RECOMMENDATIONS FOR TECHNICAL IMPROVEMENT 34
6.3.1 TRACK AND ANALYZETSCA CELL LEACHATE 34
6.3.2 EVALUATE FLOW METERS 34
6.4 CONSIDERATIONS FOR GAINING SITE CLOSEOUT 34
6.5 RECOMMENDATIONS RELATED TO GREEN REMEDIATION 34
6.6 SUGGESTED APPROACH TO IMPLEMENTING RECOMMENDATIONS 35
List of Tables
Table 3-1 Groundwater constituents of concern and the applicable cleanup standards 17
Table 3-2 RHRL treatment plant effluent standards (NYSDEC 2005) 18
Table 6-1 Cost Summary Table 36
Attachments
Attachment A: Figures or modified figures from existing reports
Attachment B: CVOC trends in Sidney Landfill monitoring wells
Attachment C: CVOC trends in RHRL monitoring wells
Attachment D: Extraction trench gradients
IX
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1.0 INTRODUCTION
1.1 PURPOSE
During fiscal years 2000 and 2001, independent reviews called Remediation System Evaluations (RSEs)
were conducted at 20 operating Fund-lead pump and treat (P&T) sites (those sites with P&T systems
funded and managed by Superfund and the states). In light of the opportunities for system optimization
that arose from those RSEs, the U.S. Environmental Protection Agency (EPA) Office of Superfund
Remediation and Technology Innovation (OSRTI) has incorporated RSEs into a larger post-construction
complete strategy for Fund-lead remedies as documented in OSWER Directive No. 9283.1-25, Action
Plan for Ground Water Remedy Optimization. Concurrently, EPA developed and applied the Triad
approach to optimize site characterization and development of a conceptual site model (CSM). EPA has
since expanded the definition of optimization to encompass investigation stage optimization using the
Triad approach, optimization during design, and RSEs. EPA's working definition of optimization as of
June 2011 is as follows:
"A systematic site review by a team of independent technical experts, at any phase of a
cleanup process, to identify opportunities to improve remedy protectiveness,
effectiveness, and cost efficiency, and to facilitate progress toward site completion. "
As stated in the definition, optimization refers to a "systematic site review," indicating that the site as a
whole is often considered in the review. Optimization can be applied to a specific aspect of the remedy
(for example, focus on long-term monitoring optimization [LTMO] or focus on one particular operable
unit), but other site or remedy components are still considered to the degree that they affect the focus of
the optimization. An optimization evaluation considers the goals of the remedy, available site data, the
CSM, remedy performance, protectiveness, cost-effectiveness, and closure strategy. A strong interest in
sustainability has also developed in the private sector and within federal, state, and municipal
governments. Consistent with this interest, OSRTI has developed a Green Remediation Primer
(http://cluin.org/greenremediation/) and now routinely considers green remediation and environmental
footprint reduction during optimization evaluations. The evaluation includes reviewing site documents,
potentially visiting the site for one day, and compiling a report that includes recommendations in the
following categories:
Protectiveness
Cost-effectiveness
Technical improvement
Site closure
Environmental footprint reduction
The recommendations are intended to help the site team identify opportunities for improvements in these
areas. In many cases, further analysis of a recommendation, beyond that provided in this report, may be
needed before the recommendation can be implemented. Note that the recommendations are based on an
independent evaluation and represent the opinions of the evaluation team. These recommendations do not
constitute requirements for future action, but rather are provided for consideration by the Region and
other site stakeholders.
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The national optimization strategy includes a system for tracking consideration and implementation of the
optimization recommendations and a provision for follow-up technical assistance from the optimization
review team as mutually agreed on by the site management and EPA OSRTI.
The 72-acre Sidney Landfill site is located on Richardson Hill Road, approximately 2 miles south of the
Village of Sidney Center in Delaware County, New York. The Richardson Hill Road Landfill (RHRL)
site is located immediately to the south of the Sidney Landfill site. The remedies at both National
Priorities List (NPL) sites have been implemented by the responsible parties, Amphenol Corporation and
Honeywell, Inc., which are the successors to Bendix Corporation and Allied Signal, Inc. These parties are
collectively referred to as the Potentially Responsible Parties (PRP) for this report.
The capture zone associated with extraction wells at the northern end of the RHRL site is considered part
of the Sidney Landfill remedy. The identification of new seeps downhill to the north from the Sidney
Landfill, the presence of an apparent hydraulic connection between the two landfills, as well as the
persistence of groundwater and sediment contamination at the RHRL site led the EPA to request a study
of optimization opportunities for the remedies at these two sites. This optimization review focuses on the
groundwater components of the remedies for the two sites and considers soil and sediment contamination
only as it may be related to groundwater contamination.
1.2 TEAM COMPOSITION
The optimization review team consisted of the following individuals:
Name
Doug Sutton
Mike Noel*
Scott Shaw*
Affiliation
Tetra Tech GEO
Tetra Tech GEO
Tetra Tech GEO
Phone
732-409-0344
262-792-1282
703-444-7000
Email
doug . sutton(S>tetratech . com
mike.noel@tetratech.com
scott . shaw@tetratech . com
* Present for the site visit
In addition, the following individual from EPA OSRTI participated in the site visit.
Kathy Yager, EPA OSRTI
1.3 DOCUMENTS REVIEWED
The following documents were reviewed. The reader is directed to these documents for additional site
information that is not provided in this report.
Sidney Landfill Record of Decision (EPA Region 2, September 1995)
Sidney Landfill Explanation of Significant Differences (EPA Region 2, September 2004)
Sidney Landfill Site Environmental Data Review Report (JTMAssoc., 2006)
Sidney Landfill Second 5-yr Review Report (EPA Region 2, June 2009)
Sidney Landfill Site Draft Enhanced Bi ode gradation Report, MW-2S Area Groundwater "Hotspot"
(MACTEC, May 2003)
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Sidney Landfill Inspection and Monitoring Program, 2007 Annual Report (JTM Associates, August
2008)
Sidney Landfill Inspection and Monitoring Program, 2010 Annual Report (JTM Associates, April
2011)
Sidney Landfill Inspection and Monitoring Program, 2008 Annual Report (JTM Associates, March
2009)
Richardson Hill Road Landfill Record of Decision (US EPA Region 2, September 1997)
Richardson Hill Road Landfill Supplemental Hydrogeologic Investigation (O 'Brian & Gere,
September 2008)
Richardson Hill Road Landfill First 5-yr Review Report (US EPA Region 2, September 2007)
Richardson Hill Road Landfill Groundwater Treatment Plant Effluent Discharge Criteria (NYSDEC,
December 1, 2005)
NYSDEC Sec. 703.5 Water Quality Standards for Surface Water and Groundwater (Current)
National Primary Drinking Water Regulations (Current)
Richardson Hill Road Landfill Site Final Interim Remedial Action Report, Remedial Work Element I,
Remedial Excavations and Capping (Parsons, August 2007)
Richardson Hill Road Landfill Site Final Interim Remedial Action Report, Remedial Work Element I,
Groundwater Extraction and Treatment (Parsons, August 2007)
Richardson Hill Road Landfill Site Operations and Maintenance Manual for Post Construction
Activities (Parsons, August 2007)
Richardson Hill Road Landfill Site 2008 Fish Tissue Sampling Results
Richardson Hill Road Landfill Site Explanation of Significant Differences (EPA Region 2, September
2008)
Richardson Hill Road Landfill Site Final Remedial Action Report for Herrick Hollow Creek
Restoration (Barton & Loguidice, March 2009)
Richardson Hill Road Landfill Site Operations and Maintenance 2009 Annual Summary Report (JTM
Associates, April 2010)
Richardson Hill Road Landfill Site Operations and Maintenance 2010 Annual Summary Report (JTM
Associates, April 2011)
Richardson Hill Road Landfill Site Operations and Maintenance Report 1st Quarter 2011 (JTM
Associates, June 2011)
Richardson Hill Road Landfill Site 2008 - 2011 process data
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1.4 QUALITY ASSURANCE
This optimization evaluation uses existing environmental data to interpret the CSM, evaluate remedy
performance, and make recommendations to improve the remedies at two focus sites. The optimization
team evaluates the quality of the existing data before data are used for these purposes. The evaluation for
data quality includes a brief review of how the data were collected and managed (where practical, the site
Quality Assurance Project Plan [QAPP] is considered), the consistency of the data with other site data,
and the use of the data in the optimization evaluation. Data that are of suspect quality are either not used
as part of the optimization evaluation or are used with the quality concerns noted. Where appropriate, this
report provides recommendations made to improve data quality.
1.5 PERSONS CONTACTED
The site visit and stakeholders meeting were held on August 23, 2011, at the Amphenol Plant (office of
one of the PRPs) in Sidney, New York. In addition to Mike Noel, Scott Shaw, and Kathy Yager, the
following persons were present for the stakeholders meeting:
Name
Affiliation
Phone
Email
Young Chang
EPA Region 2
212-637-4253
chang.voungfaiepa.gov
Edward Modica
EPA Region 2
Samuel Waldo
Amphenol
Joe Bianchi
Amphenol
David Carnevale
O'Brien & Gere
Deborah Wright
O'Brien & Gere
Richard Galloway
Honeywell
James Drumm
NYSDEC
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2.0 SITE BACKGROUND
2.1 LOCATION
The Sidney Landfill is located on the eastern side of Richardson Hill Road, approximately 2 miles south
of the village of Sidney Center in Delaware County, New York. The closest large town is Sidney, New
York, which is located approximately 10 miles northwest. The RHRL site is located south of the Sidney
Landfill, on the western side of Richardson Hill Road, and on the western side of Herrick Hollow Creek,
a north/south stream valley. The RHRL site consists of two sections designated as the "North Area" and
the "South Area." The South Area is composed of an 8-acre landfill (which contained a former waste oil
disposal pit), South Pond, and a portion of Herrick Hollow Creek. Both sites are located on the boundary
between the Susquehanna (north) and Delaware River (south) drainage divides. Figure 1-1 (see
Attachment A) illustrates the locations of these two sites with respect to each other and Richardson Hill
Road.
2.2 SITE HISTORY
2.2.1 HISTORICAL LAND USE AND FACILITY OPERATIONS
The RHRL property was purchased in 1964 to operate a landfill. In 1968, the operator agreed with the
New York State Department of Environmental Conservation (NYSDEC) to cease landfilling as a result of
a number of operational violations. The site continued to accept waste until 1969. Two areas at the site
have historically been used for landfilling: (1) the North Area, which consisted of a pair of waste
trenches; and (2) the South Area, which included approximately 8 acres used for conventional landfill
operations and a waste oil pit.
According to the Record of Decision (ROD) (EPA, 1995) the Sidney Landfill property was purchased in
1967 with the intent of operating a landfill. Landfill operations ceased in 1972. Six distinct areas of the
Sidney Landfill were used for landfill operations: (1) the North Disposal Area; (2) the Southeast Disposal
Area; (3) the Southwest Disposal Area; (4) the Alleged Liquid Disposal Area; (5) the White Goods
Disposal Area; and (6) the Can and Bottle Dump.
2.2.2 CHRONOLOGY OF ENFORCEMENT AND REMEDIAL ACTIVITIES
Sidney Landfill
The following is the chronological sequence of site investigation and remedial activities associated with
the Sidney Landfill.
Landfill operations at the site began in 1967 and ended in 1972.
From 1985 to 1987, NYSDEC conducted a Phase II site investigation of the site. Groundwater
samples collected in September 1985 and October 1986 had concentrations of several constituents
of concern (COC) that were above state and federal drinking water standards. As a result of the
investigation, the site was proposed to be included on the NPL on June 24, 1988.
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On March 31, 1989, the site was added to the NPL.
The EPA conducted a Remedial Investigation and Feasibility Study (RI/FS) at the site from 1991
to 1995.
On September 28, 1995, the EPA issued a ROD for the site, selecting a remedy that included
landfill capping, groundwater extraction, institutional controls (1C), and monitoring.
An Administrative Order was issued to the PRPs in 1996 to design and install the remedy.
The Remedial Design (RD) began in 1997.
In 1998, during a pre-design investigation, a pilot test of a blasted-bedrock trench was attempted.
During the initial installation of the trench as part of the pilot test, detonation of blasting materials
created a hydraulic inter-connection between the shallow and deep bedrock zones that effectively
dewatered the aquifer near MW-2S, a contamination "hot spot." As a result, the MW-2S hot spot
was no longer in existence and, therefore, extraction of contaminated groundwater was no longer
possible in this area.
Disposal area capping started in June 1999 and was completed by November 2000.
The site operations and maintenance (O&M) manual was approved by the EPA in 1999.
As part of an assessment of site-wide natural attenuation, quarterly groundwater sampling was
initiated in November 2001. Quarterly groundwater sampling was conducted for eight quarters.
The samples were analyzed for natural attenuation parameters and volatile organic compounds
(VOC).
In an attempt to address groundwater contamination near MW-2S, injection of Hydrogen Release
Compound (HRCฎ) to enhance contaminant biodegradation was tested at the pilot scale between
2001 and 2002. Although there was some evidence of minor reducing conditions and contaminant
degradation, it was determined that the enhanced biodegradation technology would not be a
suitable alternative at the site.
In September 2004, EPA issued an Explanation of Significant Differences (ESD) that formalized
eliminating groundwater extraction in the area of MW-2S and specified that the radius of
influence of pumping from the RHRL site is sufficient to meet the remedial action objectives
(RAO) for the Sidney Landfill remedy. In addition, as a result of the location of the main site
access road, the White Goods Disposal Area and the Alleged Liquid Waste Disposal Area were
capped and fenced off separately, rather than combining them into a single unit.
The initial Five-Year Review of the site was completed in 2004 and the second Five-Year Review
was completed in 2009.
RHRL
The following is the chronological sequence of site investigation and remedial activities associated with
the RHRL site.
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Landfill operations began in 1964 and ended in 1969. Based on the results of a Phase II site
investigation conducted by NYSDEC, the site was placed on the NPL on July 1, 1987.
On July 22, 1987, EPA entered into an Administrative Order on Consent (AOC) with the PRPs,
requiring them to complete anRI/FS and delineate the nature and extent of the contamination at,
and emanating from, the site and to identify and evaluate remedial alternatives.
From 1988 to 1996, the initial RI was conducted.
In 1993, EPA entered into an AOC with the PRPs, requiring them to investigate potential
contamination of nearby residential water supplies and install and operate whole-house supply
water treatment systems.
In 1993, a Unilateral Administrative Order was issued to the PRPs to control light non-aqueous
phase liquids (LNAPL) and excavate sediment in the hot spot of the South Pond.
In 1997, EPA signed a ROD that included excavation of contaminated waste from selected areas,
removal of contaminated sediments and soils from selected areas, installation of outlet controls on
South Pond, groundwater extraction and treatment from an extraction trench, ICs, long-term
monitoring, and installation and maintenance of water treatment systems on the contaminated
wells at two nearby residences.
The RD started and a Consent Decree for the remedy design and implementation was approved in
1999.
In 2003 and 2004, contaminated soil from outside of the landfill, polychlorinated biphenyl
(PCB)-contaminated soils from the waste oil pit, and PCB-contaminated sediments from the
South Pond area were excavated, and the groundwater extraction trench was installed.
Landfill cap installation was initiated in 2004 and completed in 2006.
A Supplemental Hydrogeologic Investigation was completed between 2006 and 2008 to (1)
assess the extent of contaminants in the shallow bedrock east of the RHRL site and South Pond
and south of South Pond; (2) define the extent of hydraulic influence of the groundwater
collection trench; and (3) identify appropriate trench monitoring and operational modifications.
The initial Five-Year Review was completed in 2007.
In 2008, EPA issued an BSD to formalize the consolidation of sediment removal into a single
event and to include additional limited groundwater extraction from downgradient of the
groundwater extraction trench to address contamination but limit dewatering of wetlands.
2.3 POTENTIAL HUMAN AND ECOLOGICAL RECEPTORS
According to the Sidney Landfill second Five-Year Review, approximately 50 property owners live
within one mile of the sites, all of which obtain drinking water from either water wells or active springs.
The September 2008 Preliminary Site Close-Out Report states that there are three residences located
between the entrances of the two NPL sites. Two of the residences are located on the eastern side of
Richardson Hill Road, and the third is located on the western side. Despite the implementation of ICs
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(Environmental Restriction Easement and Declaration of Restrictive Covenants) at both of the properties
on the eastern side of the Richardson Hill Road that run with the land, it was determined in 2011 that the
property owner had installed two household supply wells immediately south of the Sidney Landfill and
east of the RHRL.
The seeps (springs), wetlands, ponds, and streams that are present at the toe of both landfills serve as
discharge points for site groundwater. Downslope property owners, wildlife, and recreational users of
surface water features are potential receptors of site contaminants.
2.4 EXISTING DATA AND INFORMATION
The information provided in this section is intended to represent data already available from existing site
documents. Interpretation included in this section is generally from the document that supplied the
information. The optimization review team's subsequent interpretation of these data is presented in
Sections 4.0 and 5.0 of this report.
2.4.1 SOURCES OF CONTAMINATION
Sidney Landfill
The primary COCs at the site are PCBs and chlorinated volatile organic compounds (CVOC) that result
from previous disposal practices. According to the second Five-Year Review, the area where waste was
deposited is not well-documented; however, several discrete areas in different parts of the site were filled.
According to the second Five-Year Review, the following disposal areas had shown the presence of
hazardous constituents prior to remediation:
North Disposal Area (10.8 acres)
Southeast Disposal Area (6.4 acres)
Southwest Disposal Area (1.9 acres)
Alleged Liquid Waste Disposal Area (3,125 square feet)
White Goods Disposal Area (8,516 square feet)
Can and Bottle Dump Area (19,032 square feet)
Soils near the Southeast Disposal Area in an area described as the "eastern stained soil area" contained
detectable concentrations of cadmium (14.8 milligrams per kilogram [mg/kg]) and thallium (0.4 mg/kg).
Based on their presence in soil and groundwater, CVOCs were most likely part of the waste stream in one
or more parts of the site.
According to the second Five-Year Review, 1,200 cubic yards of waste was excavated from the Can and
Bottle Dump Area during remedy construction and consolidated onto the North Disposal Area, and caps
consistent with Title 6 of the New York Codes, Rules and Regulations Part 360 ("Part 360 caps") were
installed over the North Disposal Area, Southeast Disposal Area, Southwest Disposal Area, Alleged
Liquid Waste Disposal Area, and White Goods Disposal Area. The caps consisted of a 12-inch gas
venting layer, a textured 60-mil high density polyethylene (HOPE) geomembrane liner, a 24-inch barrier
protection layer, and a 6-inch topsoil layer. Each cap was enclosed by a chain-link fence. The cap
construction was completed in November 1999. The capped areas are indicated on Figure 2-1 (see
Attachment A).
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RHRL Site
The sources of contamination in the South Area include an 8-acre landfill, part of which is a former waste
oil disposal pit. The primary COCs for the RHRL site are the same as at the Sidney Landfill site, and the
highest concentrations in surface and subsurface soils were detected in the vicinity of the former waste oil
disposal pit (see Figure 2-2, Attachment A). According to the ROD, the maximum PCB concentration
detected in the original Remedial Investigation (RI) samples collected in 1990 in the subsurface soil was
14,000 mg/kg, located southwest of the former waste oil disposal pit. In the former waste oil disposal pit
itself, PCB concentrations ranged up to 7,000 mg/kg. Soil samples collected in the former waste oil
disposal pit showed a substantial reduction in contaminant levels over time. The ROD suggests that the
significant reduction in PCB concentrations in the former waste oil disposal pit and the surrounding soils,
in conjunction with the presence of high levels of PCB-contaminated sediments in South Pond before
they were excavated, appears to indicate that much of the contamination in the former waste oil disposal
pit migrated to the South Pond and caused significant sediment contamination. Based on their more
extensive presence in soil and groundwater, CVOCs were most likely part of the waste stream in the
waste oil pit and other parts of the landfill.
The North Area is located about 1,000 feet northeast of the landfill and included two disposal trenches
(approximately 70 feet by 70 feet) and a man-made surface water body called North Pond (shown on
Figure 1-1 north of the treatment plant). PCBs were also detected in surface and subsurface soils in the
North Area (field screening concentrations ranged up to 42.2 mg/kg and 0.14 mg/kg, respectively).
Elevated levels of inorganic contaminants were detected in subsurface soil samples in an area south-
southwest of the former waste oil disposal pit, the former waste oil disposal pit itself, and the North Area.
Iron, nickel, lead, and zinc were detected, with highest concentrations of 53,100 mg/kg, 37.6 mg/kg, 136
mg/kg, and 413 mg/kg, respectively. The concentrations of the remaining inorganic constituents were
within the New York State background levels.
According to the Five-Year Review, approximately 7,300 cubic yards of contaminated waste materials
and soils were excavated from the North and South Areas of the site and from the waste oil disposal pit in
the landfill.
2.4.2 GEOLOGY SETTING AND HYDROGEOLOGY
The geology, hydrogeology, and hydrology of the two sites are similar and are therefore discussed
together.
Geology
According to several of the site reports reviewed, the unconsolidated overburden at the two sites consists
of dense reddish brown to gray glacial till. For the most part, the overburden is unsaturated except near
the valley center in proximity to discharge points near the North and South Ponds. Bedrock beneath the
landfills is part of the Sonyea Group of the lower Walton Formation, consisting of non-marine, massive
gray sandstones interbedded with siltstones and shales that dip gently (2 to 3 degrees) to the east. The
depth to bedrock at the RHRL site varies from 18 feet to 39 feet below ground surface (bgs). According to
the Sidney Landfill Five-Year Review, the dominant fracture orientation is from northeast to southwest
with a secondary fracture orientation from east to west.
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Hydrogeology
Groundwater is encountered in the overburden, shallow bedrock (18 to 70 feet bgs), and the deeper
bedrock (greater than 70 feet bgs). According to the 2007 final O&M plan for the RHRL remedy, the
overburden and shallow bedrock flow regimes appear to be hydraulically connected and isolated from the
deeper bedrock groundwater flow system. Overburden groundwater flow in the vicinity of the landfills is
topographically controlled in the coarser-grained sediments within the till. Groundwater flow in the
bedrock is predominantly along bedding planes and fractures toward the center of the valley, where it
discharges to the overburden and emerges as wetlands, ponds, and streams.
There is a 0.15 feet/foot hydraulic gradient in the overburden at the RHRL site, and overburden
groundwater at the RHRL site discharges to the South Pond. Groundwater in the North Area flows to the
north toward North Pond. Bedrock at the RHRL site flows from the eastern and western uplands toward
Herrick Hollow. Water level data collected from bedrock monitoring wells at the Sidney Landfill indicate
that the hydraulic gradient in the bedrock ranges from 0.10 to 0.20 feet/foot in an east-to-west direction.
Supplemental information from the Sidney Landfill indicates that while groundwater flow is
predominantly to the west, a southwesterly flow component associated with the primary fracture
orientation is also present and contributing to the distribution of contaminated groundwater.
Water budget data collected during well installation at both sites show that little, if any, drilling fluid was
lost during drilling in the overburden, indicating that the till is relatively impermeable.
Overburden hydraulic conductivity measured during the RI varied from 0.01 to 15 feet/day. With a
hydraulic gradient of 0.15 feet/foot and porosity of 0.3, the overburden seepage velocity ranges from
0.007 to 7.5 feet/day. In bedrock, the hydraulic conductivity ranges from 2.7E-4 to 6.6 feet/day, with
groundwater primarily flowing through bedding plane fractures and not through the bedrock matrix.
Surface Water Hydrology
Surface water primarily drains from the sites into wetlands and eventually into either the North Pond or
the South Pond. The Sidney Landfill and RHRL are located on the drainage divide between the
Susquehanna and Delaware Rivers (see Figure 2-3, Attachment A). South Pond drains to Herrick Hollow
Creek. Approximately 1.5 miles south of the site, Herrick Hollow Creek discharges to Trout Creek, a
tributary of Cannonsville Reservoir. The Cannonsville Reservoir is part of the Delaware River watershed
and serves as a source of drinking water for New York City. North Pond drains to a northerly flowing
unnamed tributary of Carrs Creek that discharges to the Susquehanna River approximately 2 miles east of
Sidney, New York.
2.4.3 SOIL CONTAMINATION
Soil contamination is briefly discussed in Section 2.4.1 during the discussion of source areas. Soil
remedies have been implemented at the site and soils are not a primary focus of this optimization
evaluation. Further information regarding the soil remedies, however, can be found in the site documents
referenced by this report. It is noted that excavated soil contamination with PCB concentrations in excess
of 500 mg/kg were disposed of off-site at a Toxic Substances Control Act (TSCA)-compliant facility.
Excavated soil contaminated with PCB concentrations between 50 and 500 mg/kg at RHRL has been
consolidated in a constructed landfill on site that meets the majority of the TSCA requirements (including
double composite liner and a Resource Conservation and Recovery Act [RCRA] cap); PCBs are not
expected to migrate from this management unit. Excavated soil contaminated with PCBs less than 50
10
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mg/kg were consolidated on top of the landfill and included under a Part 360 cap. Therefore,
contaminated soils remain on site as part of the final remedy.
2.4.4 SOIL VAPOR CONTAMINATION
There is only one permanent structure not associated with the site that would potentially be affected by
vapor intrusion. A trailer associated with the house is used as a temporary vacation home. Both residences
are located between the two sites. EPA reports that soil vapor intrusion was evaluated at both residences
and determined not to pose a risk for the occupants.
Each of the capped solid waste units constructed as part of the remedy has passive landfill gas vents
whose emissions are monitored on a frequent basis.
2.4.5 GROUNDWATER CONTAMINATION
Sidney Landfill
The following CVOCs have been detected in site monitoring wells since the initial phase II site
investigation conducted by the NYSDEC in the 1980s.
Trichloroethene (TCE)
cis 1,2-dichloroethene (cis 1,2-DCE)
vinyl chloride (VC)
1,1,1 -trichloroethane (TCA)
1,1 -dichloroethane (1,1 -DCA)
PCBs have also been detected in groundwater.
CVOCs in the Sidney Landfill monitoring wells are primarily TCE and cis 1,2-DCE. Figure 2-4 (see
Attachment A) illustrates the CVOC distribution as of 2010. Attachment B provides trends of CVOC
monitoring from the fourth quarter of 2003 through 2010. Maximum CVOC concentrations during this
period were detected in MW-6D (more than 1,000 micrograms per liter [|ig/L]), which is located on the
downgradient side of the North Disposal Area. PCB sampling is now currently limited to MW-2S, MW-
6S, and MW-16S, and PCB concentrations were as high as 13 (ig/L in 2010 (MW-6S).
RHRL
At the time of the initial RI (1988 to 1996), groundwater contamination at the RHRL site was dominated
by high overburden concentrations of TCE (8,400 (ig/L) and its daughter product cis 1,2-DCE (26,000
(ig/L). As with the Sidney Landfill, TCA (1,300 (ig/L) and its daughter compound 1,1-DCA were also
detected at the RHRL site. In general, total CVOC concentrations in groundwater were greatest in the
overburden downgradient from the waste oil disposal pit. PCB concentrations were encountered in
shallow overburden at concentrations up to 1,400 (ig/L. RI data indicated that the contaminant plume was
1,200 feet wide and 400 feet long from the RHRL to the South Pond. According to the RHRL RI, VOCs
and PCBs were not detected in deeper bedrock monitoring wells.
CVOCs and PCBs continue to be monitored in site monitoring wells. Figure 2-5 (see Attachment A)
illustrates the CVOC distribution as of 2010. All of the monitoring points are located downgradient of the
landfill or downstream along Herrick Hollow Creek and are used for evaluating remedy performance.
Attachment C provides trends of CVOC monitoring from the third quarter of 2007 through 2010.
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Water quality sampling data from the RHRL North Area extraction wells have decreased slightly over
time (on the order of 10 percent to 20 percent) and ranged from approximately 30 (ig/L at RW-1 to more
than 400 (ig/L at RW-4.
2.4.6 SURFACE WATER AND SEDIMENT CONTAMINATION
Sidney Landfill
Contaminated seeps in the vicinity of the North Disposal Area were evident during the RI. NYSDEC
sampled seeps associated with the Sidney Landfill in 2010 and identified a seep along the unnamed
tributary north of North Pond with cis 1,2-DCE concentrations of approximately 15 (ig/L.
The maximum concentration of COCs detected in sediment during the Sidney Landfill RI were 80
micrograms per kilogram ((ig/kg) of PCBs, 420 (ig/kg of benzo[a]pyrene, and lower concentrations of
various VOCs in North Pond. The ROD reported that, based on the average concentrations found in North
Pond, there was no potential risk to benthic organisms in North Pond.
RHRL
At the time of the RIs in the early- to mid-1990s, concentrations of TCE (4 (ig/L) and cis 1,2-DCE (1 to 4
(ig/L) were present in the surface water of South Pond. PCBs were detected in the stream draining the
South Pond during the RI at concentrations ranging from 0.15 to 0.42 (ig/L. Surface water is no longer
sampled for CVOCs. PCBs were not detected (at a presumed detection limit of 0.05 (ig/L) in 2010 surface
water samples.
According to the ROD, concentrations of PCBs as high as 1,300 mg/kg were detected in sediments
collected from the South Pond before the initial pond excavation. Other COCs detected in South Pond
sediments included toluene (1.4 mg/kg) and cis 1,2-DCE (3.5 mg/kg). After the initial South Pond
excavation event in 1993, concentrations of these compounds had decreased below relevant standards for
all compounds.
During the RHRL RI, it was determined that PCBs were the dominant COC, with maximum
concentrations of 24 mg/kg in flood plain sediments just to the south of the pond and up to 180 mg/kg in
Herrick Hollow Creek. According to the 2008 Preliminary Closeout Report, all of the remaining PCB-
contaminated sediments exceeding 1 mg/kg from South Pond and Herrick Hollow Creek (a total of
28,520 cubic yards) were dry excavated in 2004 and consolidated on the landfill before it was capped.
Confirmatory sampling presented in the 2007 Remedial Action Report demonstrated compliance with the
1 mg/kg criterion.
Long-term sediment and surface water monitoring will be conducted to confirm that upland remediation
(landfill cap and groundwater collection and treatment) are functioning as designed and are not re-
contaminating South Pond and Herrick Hollow Creek. Although excavated sediment was replaced with
clean soil, sediment sampling in 2010 indicates detectable levels of PCBs below the sediment remedy
cleanup criterion of 1 mg/kg.
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2.4.7 FISH TISSUE CONTAMINATION
One fish sampling event was conducted in 2008 and another one was conducted in fall 2011. Fish tissue
samples were collected at multiple segments of Herrick Hollow Creek. The 2008 fish tissue results were
reviewed by the optimization review team. Wet weight PCB concentrations in creek chub and
pumpkinseed (sun fish) ranged from 720 (ig/kg to 8,000 (ig/kg for fish tissue samples collected from
South Pond (segment 21) and the upper reaches of Herrick Hollow Creek (segments 15 to 20). Fish tissue
samples collected farther downstream were generally lower than 500 (ig/kg for creek chub, but as high as
3,800 (ig/kg for brook trout.
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3.0 DESCRIPTION OF PLANNED OR EXISTING REMEDIES
This section presents information available from existing site documents. Interpretations included are
generally from the documents that supplied the information. The optimization review team's
interpretation of this information and evaluation of remedy components are discussed in Sections 4.0 and
5.0.
3.1 REMEDY AND REMEDY COMPONENTS
Sidney Landfill
The remedy outlined in the Sidney Landfill ROD included the following elements:
Waste in the Can and Bottle Dump was to be excavated and relocated to the North Disposal Area.
Four closure cap areas with Part 360 caps were to be created, as follows:
o The North Disposal Area,
o Combine the White Goods Disposal Area and the Alleged Liquid Disposal Area,
o The Southeast Disposal Area, and
o The Southwest Disposal Area.
Groundwater contamination associated with the MW-2S "hot spot" was to be extracted from a
blasted bedrock trench, treated, and discharged to surface water.
A series of ICs were to be implemented to limit potential exposure pathways.
A long-term monitoring program was to be instituted to ensure that the RAOs are being met.
Monitoring was to include a groundwater monitoring program and a site inspection program that
included landfill caps and other physical controls such as fences.
With the exception of the groundwater remediation at MW-2S, the above remedies were implemented
according to the ROD. The groundwater remedy at MW-2S was addressed by a 2004 BSD based on
changes during pre-design activities. A pilot-scale blasted bedrock trench was constructed in May 1998 as
part of the pre-design investigation for the MW-2S hot spot. Based on the results of subsequent testing, it
was determined that the blasting caused the shallow bedrock zone to become hydraulically connected
with the deeper zone, thereby dewatering the hydraulic zone monitored by monitoring well MW-2S. After
the bedrock trench had been blasted, with the exception of the sampling event in February 2000,
monitoring well MW-2S could not be sampled because the well was dry or contained an insufficient
amount of water for sampling. (The February 2000 sample results showed the presence of only TCE at
1.4 (ig/L.) As a result of these conditions, it was concluded that extraction of groundwater from the hot
spot could not effectively remove contaminants from this area. Therefore, the remedy selected in the
ROD for the MW-2S hot spot was considered no longer necessary. Additional studies suggested that
groundwater contamination at Sidney Landfill could be remediated within 22 years by the RHRL North
Area recovery system compared with 17 years with on-site pumping at the Sidney Landfill. Given the
similarity in timeframes and the significant costs associated with on-site pumping at Sidney Landfill, the
2004 BSD specified that Sidney Landfill groundwater contamination would be addressed by the RHRL
North Area recovery system and monitored natural attenuation (MNA).
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RHRL
The 1997 ROD selected a remedy consisting of the following components:
Soil and sediment excavation/dredging,
Disposal of contaminated soil exceeding 500 mg/kg PCBs at a TSCA-compliant facility,
Consolidation of contaminated soil with PCB concentrations between 50 mg/kg and 500 mg/kg in
a TSCA cell with a landfill cap consistent with 6 NYCRR Part 360,
Groundwater extraction from both the North Area via extraction wells and South Area via an
interceptor trench, and
Treatment of extracted groundwater with discharge to surface water.
According to the Five-Year Review, approximately 7,300 cubic yards of contaminated waste materials
and soils have been excavated from the North and South Areas of the site and from the waste oil disposal
pit in the landfill. In addition, a total of 28,520 cubic yards of sediments from South Pond and Herrick
Hollow Creek were dry excavated and consolidated on the landfill before it was capped. The soil and
sediment remedies have been completed, and the primary focus at the site is on landfill maintenance and
groundwater remediation.
The groundwater remedy consists of an extraction trench at the toe of the RHRL, a North Area recovery
system, and a groundwater treatment plant (GWTP). Each of these components is described in the
following sections.
3.1.1 EXTRACTION TRENCH
The extraction trench is located between monitoring wells TMW-01/TMW-02 and TMW-07/TMW-08, as
illustrated on Figure 2-2 (see Attachment A). The trench is approximately 1,150 feet long, 3 feet wide,
and extends to bedrock at an elevation ranging from 1728.5 to 1742.4 feet above mean sea level (amsl).
The northern half of the trench is an average of 10 feet deeper than the southern half. The trench is keyed
a minimum of 2 feet into dense till and bedrock. An 80-mil HOPE barrier wall was installed on the
downgradient side of the trench before it was backfilled with clean stone. Three sumps (SI through S3)
consisting of vertical 24-inch perforated pipe with submersible pumps are installed to pump groundwater
to the GWTP. Each pump is turned on or off depending upon the water surface elevation in the
corresponding sump. (Each pump is controlled independently by a separate level measuring system in the
sump.) Each sump also includes a dilute acid feed line intended to limit iron precipitation. A single
underground pipeline carries the combined flow from the three sumps to the GWTP. A flow meter at the
GWTP measures combined flow and reports it to the system computer. Figure 3-1 (see Attachment A)
depicts the trench construction and the anticipated capture zone.
There are six in-trench monitoring wells. The inner four of these in-trench wells (SSC-1 through SSC-4)
have 8-inch stainless steel casing with screened intervals within the trench and in the bedrock below the
trench. The two outer trench monitoring wells (TMW-01 and TMW-08) have 4-inch polyvinyl chloride
(PVC) casing and also are screened in the trench and in the bedrock below the trench. Monitoring wells
TMW-2 through TMW-7 are 2-inch PVC wells that are installed in the overburden approximately 4 feet
downgradient of the trench.
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Conditions encountered during early operation of the collection trench resulted in the addition of a
groundwater extraction well near the southern end of the trench. Discharge from this well is pumped to
the nearest trench sump, and the discharge is then piped to the treatment system.
3.1.2 NORTH AREA RECOVERY SYSTEM
Four groundwater recovery wells are installed in the bedrock on an approximately north-south alignment
at the downgradient edge of the VOC plume identified during the RI. The extraction wells were spaced
between 62 and 67 feet apart and installed at depths ranging from 71 to 77 feet bgs. The wells were
constructed of 6-inch-diameter stainless steel risers and a 25-foot-long, 0.30-inch slot, continuous wire-
wound screen. A 3-inch diameter Grundfos submersible pump (Model Redi-Flo3-250) is installed in each
well to pump groundwater to the GWTP. Each well is equipped with a pressure transducer to measure the
water level in the well.
3.1.3 TREATMENT PLANT
According to the Final O&M Manual, the GWTP is designed to remove oils (if present), suspended
solids, iron and other dissolved metals, VOCs, and PCBs through a series of physical-chemical treatment
processes to meet the limits specified in the site's State Pollutant Discharge Elimination System (SPDES)
discharge permit. The system design capacity is 100 gallons per minute (gpm). The following are details
of the GWTP design components:
82-foot by 60-foot pre-engineered building with an eave height of approximately 20 feet
Propane heat and a ventilation system that provides four air exchanges per hour
Permanent emergency diesel generator
One 26,000-gallon equalization tank with a mixer and heat tracing
A multi-compartment oil/water separator that includes pH adjustment to "crack" emulsified oils
pH adjustment with 50 percent sodium hydroxide to 8.5 to 9.0
Reaction treatment unit (RTU) consisting of a polyaluminum chloride (PAC) addition and
mixing, polymer addition and mixing, and flocculation tank
Inclined plate clarifier for settling of precipitated solids
Two bag filter units arranged in parallel for solids removal prior to the air stripper
One 4-tray air stripper rated for 100 gpm with a 900 cubic feet per minute (cfm) blower
Two bag filter units arranged in parallel for solids removal before the air stripper
Two 5,000-pound granular activated carbon (GAC) units arranged in a lead-lag orientation
One bag filter unit for solids removal prior to discharge
One 6,000-gallon effluent tank, which is also used to store water for backwashing the GAC
Chemical feed pumps
Process pumps
Solids pumps and holding tanks
18 cubic foot filter press
Air compressor rated for 120 pounds per square inch (psi) with a 50-gallon tank to operate the
solids and chemical feed pumps
5 parts per million (ppm) for polymer
A process flow diagram is provided in Figure 3-2 (see Attachment A).
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3.2 REMEDIAL ACTION OBJECTIVES AND STANDARDS
3.2.1 REMEDIAL ACTION OBJECTIVES
Sidney Landfill
The RAOs established for the Sidney Landfill and specified in the site ROD are as follows:
The selected remedy must minimize infiltration of surface water.
The remedy must control surface water runoff.
The remedy must be completed in a manner that mitigates off-site migration of contaminated
groundwater.
Measures must be put in place that restore groundwater quality to levels that do not exceed state
and federal drinking water standards.
Subsurface landfill gas generation and migration must be controlled through appropriate means.
Appropriate remedial efforts should be put in place to prevent contact with contamination in
groundwater.
RHRL
The RAOs established for the RHRL site and specified in the site ROD are as follows:
Reduce or eliminate contaminant leaching to groundwater.
Control surface water runoff and erosion.
Mitigate the off-site migration of contaminated groundwater.
Restore groundwater quality to levels that meet state and federal drinking water standards.
Prevent human contact with contaminated soils, sediments, and groundwater.
Minimize exposure offish and wildlife to contaminants in surface water sediments and soil.
3.2.2
CLEANUP STANDARDS
Table 1 is a summary of the maximum allowable drinking water concentrations that apply to both sites.
Table 3-1 Groundwater COCs and the applicable cleanup standards
Compound
Trichloroethene
cis-l,2-Dichloroethene
trans- 1,2-Dichloroethene
Vinyl Chloride
1,1,1 -Trichloroethane
Tetrachloroethene
PCBs
Federal Drinking Water
Maximum Contaminant Levels
(ug/L)
5
70
100
2
200
5
0.5
New York Water Quality
Standards for Surface Waters
and Groundwater
(HS/L)
5
5
5
2
5
5
0.09
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3.2.3
TREATMENT PLANT OPERATION STANDARDS
Treatment plant effluent standards for the RHRL system were established for the site in a letter from the
NYSDEC Division of Environmental Remediation on December 1, 2005. Table 2 is a summary of many
of these parameters and includes the frequency at which they must be evaluated.
Table 3-2 RHRL treatment plant effluent standards (NYSDEC, May 2011)
Parameter
Flow
Ph
Oil and Grease
Iron
Magnesium
Manganese
Lead, Total
1 , 1 -Dichloroethane
1,1,1 -Trichloroethane
1 ,2-Dichloroethene
Trichloroethene
Vinyl Chloride
PCBs (all Aroclors)
Discharge
Limitation
60,000- 145,000
6.5-8.5
15
300
94,000
800
4
10
10
10
10
0.8
0.2
Units
gpd
Standard Units
mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Frequency of
Measurement
Continuous
Daily
Weekly
Monthly
Quarterly
Quarterly
Monthly
Monthly
Monthly
Monthly
Monthly
Monthly
Weekly
gpd = gallons per day
mg/L = milligrams per liter
Hg/L = milligrams per liter
3.3 PERFORMANCE MONITORING PROGRAMS
Sidney Landfill
Inspection and maintenance are carried out on a quarterly basis to ensure that the site fence system, the
landfill covers, the drainage system, and the site monitoring wells are in good condition and operating as
planned. Quarterly environmental monitoring includes inspection of the passive landfill gas venting
system and collection and analysis of groundwater samples from site monitoring wells. Groundwater is
sampled as follows:
20 wells sampled and analyzed for VOCs
Two wells sampled for natural attenuation parameters (MW-6S and MW-6D)
Three wells sampled for PCBs (MW-2S, MW-6S, and MW-16S)
Six wells sampled for routine Part 360 parameters
RHRL
Inspection and maintenance are conducted on a quarterly basis and after major rainfall events for the
landfill cap, TSCA cell, storm water control features, access structures, and other features.
Environmental sampling includes the following:
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Groundwater monitoring includes sampling of 27 monitoring wells on a quarterly basis
o Samples from all 27 wells are analyzed for VOCs quarterly
o Samples from 12 monitoring wells are analyzed for natural attenuation parameters
annually
o Samples from 6 wells are analyzed for PCBs quarterly
o Samples from 10 additional wells are analyzed for PCBs annually
The four North Area extraction wells are sampled quarterly for VOCs
Monthly sampling of the treatment plant influent for metals, VOCs, PCBs, and other parameters
Two residential wells are sampled annually and samples are analyzed for VOCs
Three sediment samples are collected annually and analyzed for PCBs and total organic carbon
Three surface water samples are collected annually and analyzed for PCBs
Groundwater elevations are measured weekly at 43 monitoring or extraction system points
LNAPL monitoring in Sump 1 of the extraction trench
Fish tissue sampling in South Pond and Herrick Hollow Creek (2008 and 2011 only)
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4.0 CONCEPTUAL SITE MODEL (CSM)
This section discusses the optimization review team's interpretation of existing characterization and
remedy operation data and site visit observations to explain how historical events and site characteristics
have led to current conditions. This CSM may differ from that described in other site documents. CSM
elements discussed are based on data obtained from EPA Region 2 and described in the preceding
sections of this report. This section is intended to include interpretation of the CSM only. It is not
intended to provide findings related to remedy performance or recommendations for improvement.
Findings and recommendations are provided in Sections 5.0 and 6.0, respectively.
4.1 CSM OVERVIEW
Historical waste disposal resulted in PCB and VOC contamination of soil and groundwater at the Sidney
Landfill and soil, groundwater, and sediments at the RHRL site. Soil and sediment remedies have been
implemented and completed. Contaminated soil remains on site in capped disposal areas. Sediment with
PCB contamination exceeding 1 mg/kg was removed from South Pond and Herrick Hollow Creek by
excavating contaminated sediments and replacing them with clean soil. PCB-contaminated groundwater
continued to discharge to South Pond for 4 years after the sediment remedy was completed and before the
groundwater remedy was operational. The 2008 fish tissue sampling was likely influenced by the
contaminated groundwater that continued to discharge to South Pond. From 2008 until present, the
groundwater extraction trench has captured some of the groundwater contamination migrating from the
source areas, as is evidenced by decreasing concentration trends in monitoring wells downgradient of the
extraction trench. The contaminated groundwater that had previously migrated downgradient of the
groundwater extraction trench continues to discharge to South Pond and may continue to contribute to the
PCB contamination detected in sediments and fish tissue.
Groundwater contamination at both sites is present in the overburden and bedrock. Historically,
contaminated groundwater likely migrated downgradient (downhill) and vertically downward in the
vicinity of the source areas and then transitioned to an upward gradient at the bottom of the valley where
it discharged to North Pond, South Pond, and Herrick Hollow Creek. Some contaminated groundwater
(presumably the deepest contaminated groundwater) remains below the stream bed for several thousand
feet in a horizontal direction before it discharges to the stream. Generally, the highest groundwater
contaminant concentrations at the RHRL site are in the overburden, and the highest groundwater
contaminant concentration at the Sidney Landfill is in a bedrock well.
Concentrations in groundwater at the Sidney Landfill remain relatively stable, or potentially increasing
(for example, at well MW-6D), since the soil remedy was completed. The Sidney Landfill is located on a
groundwater flow divide, and groundwater flow and contaminant migration to the north are not well
understood. Seeps at the bottom of the hill to the north are impacted with CVOC contamination above
regulatory standards, suggesting that at least part of the plume is migrating to the north. The North Area
recovery system that is part of the RHRL site might address some of the contamination that migrates from
Sidney Landfill to the west or south. However, the hydraulic gradient in the north portion of the North
Area recovery system is directed away from Sidney Landfill and the hydraulic gradient at the southern
end is directed away from well RW-4 to the south. This observed pattern suggests that the wells do not
capture contamination migrating from the Sidney Landfill in the direction of these wells. Water quality
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data from the recovery wells in the RHRL North Area show that concentrations are not significantly
increasing or decreasing.
With the exception of groundwater concentrations in samples collected from well TMW-02,
concentrations detected downgradient of the RHRL extraction trench are generally decreasing. These
concentration decreases are likely the result of capture provided by the operating groundwater extraction
trench. Hydraulic data are insufficient to confirm capture, and it is too early to use water quality sampling
to determine if capture is sufficient to allow downgradient concentrations to decrease to cleanup
standards. Section 5.0 of this report further discusses interpretations of hydraulic data and water quality
data.
4.2 DATA GAPS
Data gaps in the CSM that are relevant to groundwater remedy performance are discussed in Section 5.0
Findings.
4.3 IMPLICATIONS FOR REMEDIAL STRATEGY
Implications of the CSM and data gaps in the CSM that are relevant to groundwater remedy performance
are discussed in Section 5.0 (Findings) and Section 6.0 (Recommendations).
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5.0 FINDINGS
The observations provided below are the interpretations of the optimization review team. No observations
are intended to imply a deficiency in the work of the system designers, system operators, or site
managers, but are offered as constructive suggestions in the best interest of the EPA and the public. These
observations have the benefit of being formulated based on operational data unavailable to the original
designers. Furthermore, it is likely that site conditions and general knowledge of groundwater remediation
have changed over time.
5.1 SUBSURFACE PERFORMANCE AND RESPONSE
5.1.1 GROUNDWATER FLOW AND PLUME CAPTURE
Sidney Landfill
The shallow bedrock potentiometric surface slopes generally from east to west toward the regional
topographic valley and the North Area groundwater extraction wells. During a 2003 pump test of the
North Area extraction wells, a positive drawdown response was observed at Sidney Landfill wells MW-
8D and MW-9D located 900 and 550 feet from the extraction wells, indicating good hydraulic
connection. No response or inconclusive results were observed at well nests MW-6S/D, MW-10S/D, and
MW-23, located 900, 750 and 400 feet from the extraction wells, respectively. It is important to note,
however, that drawdown is not synonymous with hydraulic plume capture. Hydraulic plume capture is
provided only if groundwater is flowing to the extraction wells, which is typically indicated by a
potentiometric surface that is directed toward extraction wells. The hydraulic gradient in the northern
portion of the North Area recovery system (near wells RW-1 and RW-2) is trending away from the
Sidney Landfill, and the hydraulic gradient in the south of well RW-4 is trending to the south away from
RW-4. From the data reviewed, the optimization review team believes there is weak evidence for
concluding that the North Area recovery system is capturing the southern portion of the Sidney Landfill.
A groundwater flow divide occurs toward the north end of the Sidney Landfill site, but there are not
enough data in the information reviewed by the optimization review team to clearly identify the location
of the divide. NYSDEC identified and sampled a seep located north of the MW-7 cluster that had CVOC
concentrations above cleanup criteria, suggesting that a portion of the plume is migrating to the north and
is not addressed by active remediation.
RHRL - Trench and RW-05
Hydraulic Responses
Groundwater flow in unconsolidated deposits converges from the east and west toward South Pond and
Herrick Hollow Creek and continues south. Groundwater elevations inside and directly downgradient
(east) of the extraction trench are generally lowest to the north (between Sumps 1 and 2) in the vicinity of
wells SSC-l/TMW-3, SSC-2/TMW-4 and RH-6S because the trench is deeper in this area and the pumps
can lower the water table to depths below the trench depth and sump in the southern portion of the trench
will allow. The northern section is also the area where South Pond is closest to the extraction trench.
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The table in Attachment D compares weekly water level elevations between pairs of wells inside and
downgradient of the extraction trench for the fourth quarter 2009, fourth quarter 2010, and first quarter
2011 time periods. This comparison shows generally inward gradients, indicating groundwater flows
toward the trench at TMW-1, SSC-2 and SCC-3 and outward gradients indicating groundwater flows
away from the trench at SSC-1, SSC-4, and TMW-8. Additionally, there are outward gradients from
TMW-5 to the RH-5 cluster and outward gradients from the TMW-6 cluster to the RH-8 cluster. The
trench design, which is based on the groundwater model, indicated that 10 percent of the water would
come from downgradient (east) of the trench. Based on these water elevations, it seems that this is not the
case for over half the trench length where an inward gradient is not present.
The hydraulic response of the in-trench wells to packer testing also differs depending on the location in
the trench. Packers were installed in the in-trench wells during the 2008 Supplemental Hydrogeological
Investigation to cut off flow from the bedrock screen interval. TMW-1 (northern end) showed a strong
response to the installed packer. TMW-8 (southern end) showed a significantly smaller response, and
SSC-4 (southern end) showed no response. The trench and sump are deeper in the northern end, which
allows for more drawdown in the trench and more induced flow from the bedrock wells. The lack of a
response in SSC-4 may be caused by one of two reasons: (1) contributions to the southern end of the
trench are substantially higher from overburden than the contributions through SSC-4 from bedrock, or
(2) the southern end of the trench has a reasonably strong connection to bedrock even in the absence of
the contribution from SSC-4.
The drawdown caused by restarting extraction after a system shutdown is also different between the
northern and southern portions of the trench (Figure 24 of the 2008 Supplemental Hydrogeological
Investigation). For most in-trench wells, there is approximately 8 feet of drawdown, and the drawdown
curve ends abruptly at what appears to be the low-level control set point for the pump. A pattern
consistent with pump cycling is then observed. The drawdown response is more typical in wells SSC-4
and TMW-8 (southern portion) and transitions smoothly from a steep drawdown decline to a steady level.
This pattern seems to suggest that extraction in the northern portion is limited to what the trench and
wells can provide and that extraction in the southern portion might be limited by the pump capacity.
There is more drawdown in the overburden for wells downgradient of the trench than in bedrock near the
northern portion of the trench (RH-6 cluster), and there is more drawdown in the bedrock than in the
overburden near the southern end of the trench (RH-8 cluster). In addition, decreases in contaminant
concentration at RH-8D and stable contaminant concentrations at RH-8S suggest more complete
hydraulic capture in bedrock than in overburden and that groundwater extraction is occurring from
bedrock from the southern end of the trench.
It is apparent from the above hydraulic data that the northern and southern portions of the trench respond
differently to pumping and that hydraulic communication between the northern and southern portions of
the trench is somewhat obstructed.
Concentration Trends
Concentration trends are decreasing in most downgradient wells, indicating that some degree of capture is
provided. Concentrations should decline to cleanup standards in the next several years if plume capture is
complete. If plume capture is not complete, the observed decreases will asymptotically approach
concentrations above the cleanup standards. Two exceptions to these observed decreases are at wells
TMW-2, which is located in the overburden downgradient of the northern end of the trench, and RH-08S,
which is located downgradient of the southern portion of the trench. Concentrations in these wells have
been stable or potentially increasing, suggesting that contamination may not be captured in these
locations.
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RW-05 was installed to address contamination observed at RH-03 and the RH-4 cluster, and RW-05
probably is providing capture of the contamination observed in these wells, but the contamination in
groundwater at these wells is not delineated farther to the south. Therefore, contaminated groundwater
may be migrating around the southern end of the extraction system.
Model Results
The groundwater modeling study conducted in 2000 to preliminarily evaluate an extraction trench design
suggested that 30 gpm would be required along a 950-foot trench to provide capture 25 feet into bedrock
and that a drawdown of 5 feet would provide that amount of flow during typical conditions. The actual
trench is 1,150 feet long, a drawdown of more than 5 feet is achieved in the in-trench monitoring wells,
but extraction rates averaged approximately 20 gpm during 2010. Therefore, overall actual flow is lower
than the modeled flow.
RHRL North Area
Groundwater elevation and cone of depression maps for the North Area groundwater extraction wells are
shown in Figures 5-1 and 5-2 (see Attachment A). The performance objective is at least 1 foot of
drawdown in the North Area monitoring wells compared with the non-pumping conditions noted in the
O&M plan. This is generally being achieved (NMW-9 is the only exception); however, it should be noted
that the "target levels" reported in Table 2 of the 2009 RHRL Annual Report and Table 10 of the 2010
RHRL Annual Report are the non-pumping conditions based on the table on page 3-8 of the O&M plan.
The actual "target levels" are 1 foot lower than the non-pumping conditions specified on page 3-8 of the
O&M plan. Even with this adjustment or correction, the criteria are being met. As discussed in the
section on plume capture for Sidney Landfill, it is unclear whether these wells are providing the level of
capture anticipated despite meeting performance criteria. The 2000 modeling study suggested that the
four wells would pump a total of 10 gpm. During 2010, the average total pumping rate was approximately
2.5 gpm.
5.1.2 GROUNDWATER CONTAMINANT CONCENTRATIONS
Sidney Landfill
The Sidney Landfill VOC plume has relatively low to moderate contaminant concentrations across an
area 2,500 feet long and 1,700 feet wide. The highest contaminant concentrations occur at the
downgradient edge of the North Disposal Area at monitoring well MW-6S. The time-concentration trend
plots (Attachment B) show nearly all the wells with no long-term trend except MW-6D and MW-8S,
which show an increasing trend. These data suggest the plume will require a relatively long time to
attenuate and meet groundwater standards. The undulating spikes in concentrations appear to coincide
with fluctuations in water levels. Higher water levels caused by precipitation generally result in dilution,
which lowers concentrations. Conversely, concentrations generally increase when water levels decline.
RHRL
The groundwater plume in the upper bedrock unit from the RHRL has migrated to the southeast and then
trends more southerly along the Herrick Hollow Creek valley, extending approximately 6,000 feet south
of South Pond (Figure 5-3, Attachment A). The core of the plume passes through monitoring wells RH-
05D and RH-02. Given the age of the landfill and the relatively slow groundwater velocities, this plume
was established before the extraction trench was installed.
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Time concentration charts for groundwater monitoring wells are provided in Attachment C. All of the
upper bedrock wells show a decreasing trend in VOC concentrations (TCE, DCE, and VC). As discussed
in the section on plume capture at the RHRL site, these trends suggest a degree of capture, but the degree
of capture cannot be ascertained until concentrations stabilize. If concentrations stabilize below cleanup
standards, then plume capture is adequate and this and other downgradient portions of the aquifer should
eventually exhibit decreases in concentrations to below cleanup standards. If concentrations stabilize
above cleanup standards, then capture is incomplete. Even if capture is complete, the current downward
trend in concentrations suggests it will require a relatively long time for the downgradient plume to
attenuate and meet groundwater standards.
The extent of the plume is much more limited in the unconsolidated deposits (Figure 5-4, Attachment A).
The highest contaminant concentrations occur adjacent to the South Pond in wells TMW-03, TMW-04,
and RH-06S. These three shallow wells have also historically had frequent detections of PCBs above
groundwater standards. This downgradient overburden groundwater appears beyond the capture of the
trench and will ultimately discharge to South Pond. Given this scenario, it is possible that PCB
concentrations in groundwater that discharge to South Pond may be the cause of observed PCB
concentrations in the sediment along the west edge of the pond. The degree of capture provided by the
trench in this area is uncertain because outward gradients are observed at SSC-l/TM-3 and inward
gradients are observed at SSC-2/TM-4. RH-6S is between these two locations.
RHRL North Area
Water quality data from the recovery wells in the RHRL North Area show that CVOC concentrations in
groundwater have decreased by approximately 10 percent to 20 percent. They also show that TCE and cis
1,2-DCE are the CVOCs with the highest detected concentrations. Blended influent CVOC concentrations
to the treatment plant are lower than the CVOC concentrations detected at RHRL North Area wells and
also show a general decrease. These results suggest that the CVOC concentrations in the blended
groundwater extracted from the trench are lower than the CVOC concentrations in the RHRL North Area
wells.
5.1.3 SURFACE WATER AND SEDIMENT CONTAMINATION
Sediment sampling was conducted in 2010 at three locations, and the PCB concentrations in all three
locations were below the original cleanup criterion of 1 mg/kg. Surface water sampling was also
conducted in 2010 at three locations, and the PCB concentrations in all three locations were below the
detection limit of Method 8082A of (presumed to be 0.05 (ig/L). Both sediment and surface water
samples reflect substantial improvement over pre-remediation conditions and do not suggest a decline in
water quality since remediation. It is noted, however, that a more extensive sampling program for
sediment or surface water could result in different findings. In addition, PCB concentrations lower than
the 0.05 (ig/L detection limit may be present and could continue to pose a risk to wildlife.
5.1.4 FISH TISSUE CONTAMINATION
The 2008 fish tissue sampling results include PCB concentrations that indicate exposure offish to high
levels of PCB contamination (wet weight fish tissue PCB concentrations up to 8,000 (ig/kg). The
optimization review team only reviewed the results and not the field sampling notes, field sampling
protocols, or QAPP. In addition, a complete report discussing the sampling effort was not prepared.
Therefore, analysis by the optimization review team is subject to some uncertainty. Although the
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sediment remedy was completed in 2004 and the groundwater remedy began operating in late 2004, PCB-
contaminated groundwater between the trench and South Pond continued to discharge to South Pond.
The PCBs in the discharging groundwater likely impacted the fish tissue and resulted in detectable
concentrations of PCBs in the soil that had been placed in the pond during the sediment remedy. The
2008 fish tissue sampling results may, therefore, be explained by PCB-contaminated groundwater that
continued to discharge to the pond and possibly to PCB levels already present in fish from pre-remedy
conditions. The 2011 and other future fish tissue sampling results will help determine if the PCB
concentrations in fish tissue continue to decline as a result of remediation or remain elevated through
continued exposure to PCBs.
5.2 COMPONENT PERFORMANCE
5.2.1 EXTRACTION NETWORK
Subsurface performance of the extraction network is discussed above. According to the RHRL treatment
plant operator, it is necessary from time to time to clean conveyance lines and trench sump pumps
because of biological fouling and mineral accumulation (Figure 5-5). It may be possible that similar
fouling conditions exist in the collection trench gravel and may be further reducing the ability of the
trench to intercept the RHRL contaminant plume.
The extraction pumps in the extraction trench sumps are Grundfos Redi-Flo 4 pumps rated for 25 gpm
each. The extraction pumps in the North Area are Grundfos Redi-Flo 3 pumps rated for 5 gpm each. The
pumps in both systems are controlled by high and low controls set to prevent dewatering of the sumps and
so to prevent damaging the pumps.
5.2.2 GROUNDWATER TREATMENT PLANT
The GWTP routinely meets the compliance monitoring requirements. The pH adjustment for oil recovery
is not used. The only observable oil is in Sump 1, and it is addressed manually with adsorbent socks.
Chemical usage varies on a monthly basis, but typical usages are as follows:
50 to 70 gallons per month of 50 percent caustic for pH adjustment
150 to 250 gallons per month of PAC
50 pounds per month of diatomaceous earth
2.5 gallons per month of polymer
All of the above chemical usage is for metals removal, primarily manganese.
GAC usage was not documented in the files provided to the optimization review team.
The GWTP is staffed by two full-time operators during the week. Responsibilities include changing bag
filters approximately three times per week, routine maintenance of items, operating the filter press
(approximately two to three times per month), and collecting weekly water level measurements at
recovery system monitoring points.
The optimization review team believes that:
The air stripper is an appropriate treatment technology to treat the CVOCs,
GAC is an appropriate treatment technology treat PCBs,
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PAC is an effective technology for metals removal, and
Bag filters are an appropriate technology for filtration given the solids loading and bag filter use.
The GWTP is likely overstaffed with two full-time operators, but the operators noted that two operators
are used to address healthy and safety concerns given the relative remoteness of the site.
5.3 REGULATORY COMPLIANCE
The GWTP routinely meets the compliance monitoring requirements.
5.4 COMPONENTS OR PROCESSES THAT ACCOUNT FOR MAJORITY OF ANNUAL
COSTS
A breakdown of costs was not provided to the optimization review team. The EPA Preliminary Close Out
Report states that operating costs were estimated to be approximately $500,000 per year in 2006. The
optimization review team estimates that the costs are likely significantly higher when the following are
included for both sites:
Project management, consulting, and report preparation
Operator labor
Electricity usage
Chemical usage
Propane for heating
Waste disposal
Quarterly groundwater sampling at both sites
Laboratory analysis
5.5 APPROXIMATE ENVIRONMENTAL FOOTPRINTS ASSOCIATED WITH
REMEDY
The optimization review team estimates based on professional judgment and experience at other sites that
the primary contributors to the remedy footprints associated each of the EPA green remediation core
elements are as follows:
Energy usage - electricity use and propane for building heat,
Greenhouse gas emissions - electricity use and propane for building heat,
Nitrogen oxide, sulfur oxide, and particulate matter emissions - electricity use and propane for
building heat,
Hazardous air pollutant emissions - air stripper off-gas,
On-site water usage - no significant footprint because extracted and treated water is discharged to
the same creek where it would naturally discharge,
Materials usage - treatment chemicals, and
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Waste generation - dewatered solids from metals removal.
5.6 SAFETY RECORD
The site team did not report any safety concerns or incidents.
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6.0 RECOMMENDATIONS
Cost estimates provided herein have levels of certainty comparable to those done for CERCLA Feasibility
Studies (-30 percent/+50 percent), and these cost estimates have been prepared in a manner generally
consistent with EPA 540-R-00-002, A Guide to Developing and Documenting Cost Estimates During the
Feasibility Study, July, 2000. The costs presented do not include potential costs associated with
community involvement that may be conducted before field activities. The costs impacts of these
recommendations are summarized in Table 6-1.
6.1 RECOMMENDATIONS TO IMPROVE EFFECTIVENESS
6.1.1 DELINEATE CONTAMINANT MIGRATION PATHWAYS
A review of topography and groundwater elevations across the two sites confirms the presence of a
drainage divide between the Susquehanna and Delaware River watersheds. The degree to which the
divide affects the distribution of contaminants between the sites is poorly understood. Given that the
primary regional bedrock fracture orientation is from northeast to southwest, it is possible that
groundwater coming from the southern and southeastern portions of the Sidney Landfill is flowing toward
the RHRL site. However, potentiometric surface maps also suggest groundwater flow paths to the north,
and NYSDEC identified a seep with contamination above cleanup standards more than 200 feet north of
the MW-7 cluster. The highest contaminant concentrations are from groundwater sampling at monitoring
wells MW-6S (PCBs) and MW-6D (CVOCs, but analysis is not conducted for PCBs). Similar
concentrations are not identified downgradient of this location despite potentially decades of transport. It
is unclear if this contamination discharges to North Pond, migrates north in the subsurface, migrates south
around the North Area extraction, or migrates and is at least partially captured by the North Area
extraction trench.
The first step in clarifying flow paths is to use water levels from all existing wells at both sites plus water
levels in North Pond and South Pond to develop potentiometric surface maps for the area. This should be
used as the routine approach to quarterly water level measurements at the two sites. In addition,
groundwater sampling should be conducted for those wells that are near or could bracket the potential
migration pathways, including MW-7S, MW-7D, MW-23, MW-26, MW-8DD, MW-9D, MW-10S, MW-
10D, several of the North Area monitoring wells, and various observed seeps. The contaminated seep
discovered by NYSDEC is along the unnamed tributary to Carr Creek where the topography steepens
significantly. A search for seeps and sampling for contamination should be conducted farther
downstream. Sampling at the monitoring wells and seeps should include analysis of PCBs. Existing
sampling data from the RI should also be revisited to provide additional input.
Based on the results, the site team may identify potential locations for monitoring wells or piezometers.
If discharge to North Pond is suspected, resampling sediment or pore water beneath the pond should be
revisited.
Conducting comprehensive water level events should not significantly increase the cost because the
majority of water levels are already collected. Upfront costs of approximately $10,000 would be needed
to install and survey staff gauges in North Pond and South Pond. Slightly increased costs would be
associated with collecting measurements at several new locations and interpreting the more complex
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results. The seep search should likely require approximately $10,000 to conduct and summarize. The
sampling (assuming four quarterly events based on fluctuations observed concentrations at other wells)
would likely cost an additional $15,000 per event. The need for continued sampling at these locations or a
change in frequency can be evaluated after the first four events. Sampling of representative North Area
wells for VOCs and PCBs should become part of the routine monitoring program.
6.1.2 UPDATE GROUND WATER FLOW MODEL AND EVALUATE CAPTURE
A reasonably constructed groundwater flow model was developed for the site and was used in designing
the remedy. Now that the remedy is installed and data are available from routine operation and from the
2008 Supplemental Hydrogeologic Investigation, the model should be updated and recalibrated to better
evaluate contaminant transport at the Sidney Landfill and plume capture by the North Area recovery
system, the extraction trench, and RW-05. The model would benefit from the comprehensive water levels
discussed in Section 6.1.1. Before the modeling is conducted, the site team should consider relocation of
one or more of the pumps from the sumps to the SSC wells, especially for the southern portion of the
trench. Operating the trench in this manner will allow for higher pumping rates that will better influence
the aquifer. It will also provide a different pumping scenario to model, which is helpful for improving
model calibration. Conducting the pumping tests from the SSC wells should cost approximately $35,000,
including preparation and reporting. Updating the model and recalibrating it should cost approximately
$50,000. The model should be calibrated to transient data from the 2008 investigation and the SSC
pumping and to two different comprehensive water level events. Once capture is evaluated, the site team
will have the information to determine if pumping should continue from the SSC wells or if pumping
from the sumps provides a sufficient degree of plume capture.
6.1.3 POTENTIALLY EVALUATE PCB SEDIMENT CONTAMINATION IN SOUTH POND
The capture zone of the extraction trench does not extend into South Pond. As a result, existing PCB
groundwater contamination between the downgradient boundary of the trench capture zone and South
Pond will continue to discharge to South Pond for some period after trench operation began. This period
of time may be several years, despite the short distance, for two reasons: (1) the operation of the
extraction trench has flattened the hydraulic gradient between the trench and the pond and the
groundwater flow that will flush the contamination may be relatively slow; and (2) PCBs adsorb strongly
to organic material on soils and will desorb slowly into groundwater overtime. Additionally, some level
of PCB flux could continue indefinitely if capture of PCBs up gradient of the trench is incomplete (see
Section 6.1.2). The continued flux of PCB contamination via groundwater to South Pond since 2004 may
have been sufficient to cause the low-level PCB contamination of the sediments and to influence the 2008
fish tissue results. If PCBs from up gradient of the trench are captured, the flux of PCBs to South Pond
should decrease slowly overtime.
The optimization review team suggests comparing the 2011 and 2008 fish tissue sampling results to
determine if there has been a measureable improvement 3 years after remediation. If there is a noticeable
improvement and sediment and surface water sampling in future events continues to meet post-
remediation expectations, then more extensive sampling of South Pond is likely not merited. Continued
sediment, surface water, and fish tissue sampling would likely be sufficient to monitor continued
improvements over time. However, if the 2011 and 2008 fish tissue sampling results are comparable, then
it would appear that PCBs are continuing to be exposed to relatively high levels of PCBs from
groundwater. The optimization review team would not expect PCB concentrations in wet weight fish
tissue to be as high as several mg/kg in short-lived fish such as creek chub and pumpkinseeds 7 years
after remediation if the only PCB exposure is to less than 1 mg/kg in sediments. Therefore, if the 2011
fish tissue sampling results are comparable to the 2008 results, then additional attention is merited to
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determine if the PCB flux is generally decreasing overtime or is remaining constant because of a lack of
plume control. A monitoring program that could evaluate that flux overtime would be helpful. The
current sediment and surface water monitoring program alone would not likely provide this information.
There are several options for evaluating the PCB contributions from groundwater over time. For example,
the site team could consider one of the following:
Collect pore water samples in several locations to evaluate the concentration and estimated flux
of PCBs from groundwater to sediments and surface water. This approach might be implemented
by installing sampling points through the sediments of South Pond and obtaining both filtered and
unfiltered samples via low-flow sampling. This approach would help minimize the bias from
PCB-contaminated suspended solids. The sampling points could be left in place and monitored
over time until a discernible trend is identified.
Use passive, in situ concentration-extraction samplers (PISCES) at multiple locations and near
the bottom of South Pond to sample for low levels of PCBs at the interface of groundwater and
surface water. This sampling approach involves PCBs passing through a semi-permeable
membrane and partitioning into a hexane sampling medium. Temperature is also monitored, and
PCB concentrations in surface water are back-calculated based on known relationships of the
sampling rate to temperature and sampler membrane area. The method yields time-integrated
samples over a 14-day period and is effective at detecting low concentrations in water. The
samplers, therefore, have a higher likelihood of identifying PCBs at the groundwater surface
water interface than surface water grab sampling. The samplers have been reported to
preferentially sample the lower weight PCBs because the heavier PCBs are typically adsorbed to
suspended solids that cannot pass through the membrane. Therefore, the samplers may
preferentially sample the lower weight PCBs detected in groundwater (which is primarily
reported as Aroclor 1242 at this site) and not the higher-weight PCBs detected in fish (which is
primarily reported as Aroclor 1254 at this site). The approach would likely be effective at
identifying areas impacted by contaminated groundwater, but the signature of the PISCES results
may not directly overlap with the fish tissue results. There is overlap in the molecular weight of
PCBs in Aroclor 1242 and Aroclor 1254 (for example, PCBs with five chlorine molecules
comprise a significant percentage of both Aroclors), so the difference in signatures should not
suggest that the PCB results are unrelated. This sampling approach could also be repeated over
time until a discernible trend is identified.
The optimization review team suggests using one of the two sampling methods above in up to five
locations in areas of South Pond or Herrick Hollow Creek where discharge of PCB-contaminated
groundwater would be expected (such as near RH-06S). This sampling could be done on an annual basis
in place of the surface water sampling in the current O&M plan. Sediment sampling as conducted in 2010
could also occur on an annual basis. Fish tissue sampling might be done once every 5 years. Several years
of this sampling program should provide sufficient information to see if conditions are improving, staying
the same, or getting worse. If conditions get worse during the next 5 years, the site team could consider
additional studies to identify the extent of contamination and a potential means of removing or controlling
that contamination.
If after the 2011 results have been evaluated, the site team decides to implement the above changes to the
sampling program, the optimization review team estimates that up to $15,000 might be needed to
document and plan the program, an additional $15,000 might be needed to install the sampling points
(Option 1 only), and annual costs may be $1,000 to $5,000 higher than the current sediment and surface
water sampling.
-------
6.1.4 REPORTING NORTH AREA WATER LEVELS
When the water levels in the North Area are reported, the target levels that are provided for comparison
should be 1 foot lower than the non-pumping conditions presented in the O&M plan.
6.1.5 MONITOR INSTITUTIONAL CONTROLS
In light of the recent residential well that was installed within the plume area, the site stakeholders should
develop a plan to routinely check that the ICs in place are enforced so that future potential violations of
the ICs are identified early or prevented.
6.1.6 MONITOR EXTRACTION TRENCH FOR POTENTIAL FOULING
According to the RHRL treatment plant operator, it is necessary from time to time to clean conveyance
lines and trench sump pumps because of biological fouling and mineral accumulation. It may be possible
that similar fouling conditions exist in the collection trench gravel and may be further reducing the ability
of the trench to intercept the RHRL contaminant plume. Trench flow rates have been decreasing over
time, but this observed decrease has not been correlated to precipitation, which could be the cause, or
partial cause. The site team should continue to monitor trench extraction rates for given in-trench water
level set points to determine if the specific capacity of the trench is decreasing, and if so, develop a
rehabilitation plan. There should be negligible cost for including the data analysis for trench evaluation in
routine reporting. The costs for a rehabilitation plan, if needed, are not estimated here.
6.2 RECOMMENDATIONS TO REDUCE COSTS
6.2.1 EVALUATE POTENTIAL FOR REDUCING OPERATOR LABOR
Labor associated with day-to-day site operations appears to be in excess of what should be required for
the GWTP. Treatment systems with these treatment components can typically be operated by 1 to 1.5 full-
time equivalent operators. One example is the EPA-lead site Pentawood Products in Daniels, Wisconsin,
which as with treatment plants at many other Superfund sites, is relatively isolated, but is operated
efficiently, effectively, and safely by one operator. Safety protocols can be established, such as routine
check-in calls, security cameras to monitor on-site staff, and additional alarms. Emergency first
responders should be contacted and introduced to the site so that emergency response can be timely. It is
possible that these measures at this site would provide an adequate response time to emergencies
comparable to many other Superfund sites that are similarly safely operated. Alternatively, if an
appropriate working area is available at the site, the treatment plant could serve as a base of operations for
other staff who are working on other projects. Staff who are at the plant doing office work for other
projects or a company overhead function could be present as a health and safety contact without charging
to the RHRL GTWP operations. Staff can be scheduled as appropriate to assist with those tasks that
require two individuals to be conducted safely.
To facilitate this change, the site team can discontinue the weekly water level measurements. These
measurements are no longer used or interpreted, and changing to a monthly frequency will provide an
operator with more time to address more critical, necessary items.
32
-------
The optimization review team estimates that reducing operator labor by 0.5 to 1 full-time equivalent
operator could lead to savings of $65,000 to $130,000 per year. Implementing some procedures and
protocols to improve safety as described above would cost approximately $25,000.
6.2.2 CONSIDER USING PDBs FOR VOC SAMPLING
The site team should consider the use of passive diffusion bags (PDB) for most of the groundwater
sampling events completed at both sites. PDBs are low-density polyethylene bags filled with deionized
(DI) water that are suspended in the water column in each well between sampling events. In time and as a
result of the low-density nature of the material that makes up the samplers, the DI water reaches chemical
equilibrium with surrounding groundwater. The cost savings associated with the use of PDBs includes
elimination of the need to purge monitoring wells, elimination of the need to return numerous times to
collect samples from low producing wells, and elimination of trips to the GWTP to dispose of purge
water. Wells that are sampled for other parameters (for example, some natural attenuation parameters,
metals, and PCBs) will not be suitable for PDBs. Assuming PDBs can be used at a total of 40 wells
between the two sites, sampling costs might be reduced by $32,000 per year. Cost savings during the
initial year may be lower because multiple PDBs may need to be placed in monitoring wells with long
screened intervals to determine which portion of the screened interval is appropriate for sampling.
6.2.3 ELIMINATE LABORATORY ANALYSIS FOR NATURAL ATTENUATION
Natural attenuation of chlorinated solvent compounds occurs through processes broadly referred to as
reductive dechlorination. Significantly reducing conditions ([Oxidation Reduction Potential [ORP] less
than approximately -100 millivolts) must be present in groundwater for these processes to take place.
Under the current groundwater monitoring plan, parameters like ORP and dissolved oxygen (DO) as
wells as tests for various electron acceptors are routinely included in groundwater monitoring efforts.
Data from the RHRL Supplemental Hydrogeologic Investigation and the Sidney Landfill Environmental
Data Monitoring Review indicate that while conditions that support natural attenuation of chlorinated
solvents exist in some locations, the distribution of reducing conditions is not wide-spread. Time series
plots of TCE and TCA as well as their degradation products indicate that the attenuation processes taking
place are probably dominated by diffusion, dispersion, and adsorption rather than reductive
dechlorination. Reductive dechlorination under historical conditions may have been responsible for
converting TCE to cis 1,2-DCE and some VC, but sequential decreases from TCE to cis 1,2-DCE to VC
are generally not present. Eliminating this analysis should reduce costs by approximately $8,000 per year.
Sampling for these parameters could continue in select locations where evidence for natural attenuation is
strong and contamination is not addressed by pumping.
6.2.4 CONSIDER POTENTIAL MODIFICATIONS TO THE GWTP TO HELP REDUCE LABOR
COSTS
The optimization review team reviewed in the influent water quality data since 2008 and identified that
iron and manganese are the only metals that require treatment. Influent concentrations for these two
metals are approximately 0.5 mg/L for iron and 2 mg/L for manganese. A single exception is one monthly
influent sample out of more than 30 samples that had an anomalously high copper concentration of 11.3
(ig/L compared with a discharge standard of 4.1 (ig/L. Although the current treatment process of metals
removal is effective at meeting discharge criteria, it requires more operator attention and may not be as
cost-effective as using greensand filtration. An appropriately designed greensand filtration system with an
automated sodium permanganate feed and automated backwash can operate with minimal operator
attention. One example is the treatment system at the Westside Industries site that is part of the North
33
-------
Penn Area 6 site in Lansdale, Pennsylvania. The system includes bag filters, greensand filtration, air
stripping, vapor phase treatment for the air stripper off-gas, and GAC polishing for the air stripper
effluent. The system is able to operate continuously with less than 16 hours of operator attention per
week. The system flow rate and iron and manganese loading are comparable to those at RHRL, and the
treatment system operates for under $100,000, excluding analytical costs, project management, and
reporting. Thus, a substantial reduction in operator labor can be realized. The site team might evaluate the
use of greensand filtration in place of the current metals removal system, especially if efforts to
implement recommendation 6.2.1 are not successful. The costs for designing and implementing this
system might be approximately $150,000. The materials and disposal costs for operating the system are
likely comparable to those of the existing system, but the operator labor would be significantly lower,
perhaps saving more than $150,000 per year.
6.3 RECOMMENDATIONS FOR TECHNICAL IMPROVEMENT
6.3.1 TRACK AND ANALYZE TSCA CELL LEACHATE
In 2010, 9,550 gallons of leachate was removed from the TSCA cell. The site team should compare this
amount with cap performance expectations and track the leachate quantity quarterly to evaluate whether
the cap is performing as expected. The optimization review team expects that leachate quantities would
decrease if the cap is working appropriately. If leachate quantities continue to be present or increase, the
site team should consider if the water is coming through the cap or side wall and if the leachate is
continuing to impact groundwater. Leachate quality should also be analyzed quarterly for VOCs and
PCBs so that quality can be tracked over time. This additional tracking and sampling should likely cost
approximately $1,000 per year.
6.3.2 EVALUATE FLOW METERS
During the site visit, it became apparent that a discrepancy may exist between the volume of water
extracted from the North Area wells and the South Area trench and the volume of water discharged at the
plant outfall. The discrepancy itself is not a significant concern to the optimization review team. For
quantifying overall flow, however, the site team can confirm the effluent flow meter is working and
calibrated and use the values for that flow meter. The optimization review team does not see the need to
revisit old data or identify the cause of the discrepancy; rather, the recovery well and sump flow meters
should be evaluated so that flows from individual extraction points can be tracked and considered during
capture zone evaluations. Maintenance and calibration of individual flow meters should be included in the
routine plant operator scope of work.
6.4 CONSIDERATIONS FOR GAINING SITE CLOSEOUT
No considerations for gaining site closeout are offered at this time.
6.5 RECOMMENDATIONS RELATED TO GREEN REMEDIATION
No green remediation recommendations are provided, but recommendations in Section 6.2 may result in
reducing aspects of the remedy footprint.
34
-------
6.6 SUGGESTED APPROACH TO IMPLEMENTING RECOMMENDATIONS
The optimization review team believes that the recommendations in Section 6.1 should be emphasized.
All other items can be considered at any time, with the exception of 6.2.4, would be somewhat contingent
on what is learned from implementing the 6.1 recommendations and recommendations 6.2.1 and 6.3.1.
35
-------
Table 6-1 Cost Summary Table
Recommendation
6.1.1 DELINEATE
CONTAMINANT
MIGRATION PATHWAYS
6.1.2 UPDATE
GROUND WATER FLOW
MODEL AND EVALUATE
CAPTURE
6.1.3 POTENTIALLY
EVALUATE PCB SEDIMENT
CONTAMINATION IN
SOUTH POND
6.1.4 REVIEW DATA
QUALITY
6.1.5 MONITOR
INSTITUTIONAL CONTROLS
6.1.6 MONITOR
EXTRACTION TRENCH FOR
POTENTIAL FOULING
6.2.1 EVALUATE
POTENTIAL FOR REDUCING
OPERATOR LABOR
6.2.2 CONSIDER USING
PDBS FOR VOC SAMPLING
6.2.3 ELIMINATE
LABORATORY ANALYSIS
FOR NATURAL
ATTENUATION
6.2.4 CONSIDER
POTENTIAL
MODIFICATIONS TO THE
TREATMENT PLANT TO
HELP REDUCE LABOR
COSTS
6.3.1 TRACK AND
ANALYZE TSCA CELL
LEACHATE
6.3.2 EVALUATE FLOW
METERS
Reason
Effectiveness
Effectiveness
Effectiveness
Effectiveness
Effectiveness
Effectiveness
Cost reduction
Cost reduction
Cost reduction
Cost reduction
Technical
improvement
Technical
improvement
Additional
Capital
costs ($)
$80,000
$85,000
$15,000 to
$30,000
$0
Estimated
Change in
Annual Costs
($/yr)
$0
$0
$1,000 to
$5,000
$0
Estimated
Change in
Life-Cycle
Costs $*
$80,000
$85,000
$45,000 to
$180,000
$0
Discounted
Estimated
Change in
Life-Cycle
Costs $**
$80,000
$85,000
$35,000 to
$128,000
$0
Not estimated
$0
$25,000
$0
$0
$150,000
$0
$0
$0
($65,000)
to
($130,000)
($32,000)
($8,000)
($150,000)***
$1,000
$0
$0
($1,925,000)
to
($3,875,000)
($960,000)
($240,000)
($4,350,000)
$30,000
$0
$0
($1,249,000)
To
($2,523,000)
($627,000)
($157,000)
($2,790,000)
$20,000
$0
* Assumes additional 30 years of system operation
** Assumes a discount rate of 3%
*** Project cost savings are not in addition to those from Recommendation 6.2.1.
36
-------
ATTACHMENT A
The figures presented in this attachment are from existing site documents with a figure number
specific to this report added to facilitate reference to them. In some cases, annotations may have
been added to illustrate a specific site feature.
-------
FIGURE 1
SIDNEY LANDFILL
ENVIRONMENTAL
MONITORING
PROGRAM
SITE MAP
Figure 1-1 - Sidney Landfill and RHRL
Locations and Surrounding Features
LEGEND
NOTES:
1. TOPOGRAPHIC SURVEY FROM MALCOLM PIRNIE; JANUARY 1995.
2. ADAPTED FROM MAPS AND ILLUSTRATIONS PREPARED BY HARDING E
ASSOCIATES.
environmental consulting
-------
\ -'
^ RH-02
NORTH AREA GROUNDWATER
RECOVERY & MONITORING AREA
Approximate location of
former waste oil
disposal pit
LEGEND
DUAL-ZONE TRENCH
* MONITORING WELL
ฉ HOMEOWNER WELL
4 MONITORING WELL
$ RECOVERY WELL
ฃ SUMP
GROUNDWATER RECOVERY TRENCH
I CAPPED LANDFILL
RICHARDSON HILL ROAD LANDFILL SITE
SIDNEY CENTER, NEW YORK
SITE PLAN
0 150 300
G
QBniENGGERE
-------
...''j~''^-~^:.-.:.-vvvyjv.itijj.'J/j j xfc? JYIHK:>^-=^=^-'^=^-:^ffY:7/
^-'.'^> -<>->- ^.., -~-..-- // // / . i'"' f ^ ' f~' '' "'!..' 1- -:-.-"^_ ix'^'i' M i / 'i
s/Z^'ZS's --r.>--V:j%c^to Susquehannei River ^^^if|-V.\ //
Figure 2-3. Topography
and Drainage Divide
Sidney Center/
' "'//I
Richardson
Road Landfill
This document was developed in color. Reproduction in B/W may not represent the data as intended
ADAPTED FROM: TROUT CREEK, WALTON WEST, UNADILLA, AND FRANKLIN USGS QUADRANGLES
RICHARDSON HILL ROAD LANDFILL SITE
SIDNEY, NEW YORK
QUADRANGLE LOCATION
SITE LOCATION
0 1,000 2,000 4,000 6,000 8,000
Feet
EJBRIENGGERE
FILE NO. 3729/42138
AUGUST 2008
1:24,000
-------
TCE
1,2-DCE
MW-17
TCE
1,2-DCE
1010
3.6
5.6
1Q10
1.6
2.5
2Q10
5.3
4.2
2Q10
2.3
4.8
3Q10
NS
NS
3010
2
3.2
4010
5.2
3.5
4Q10
2.6
7
MW-14S
TCE
1,2-DCE
TCE
1,2-DCE
1010
5.5
7
2Q10
5.7
8.1
3Q10
9.8
16
4Q10
4.9
8.5
MW-1D
TCE
1,2-DCE
1,1-DCE
VC
1,1,1-TCA
1,1 -DCA
s\
MW-3S
TCE
1,2-DCE
1,1,1-TCA
1,1 -DCA
MW-16S
TCE
1,2-DCE
1Q10
20
24
ND
ND
1.3
3.4
f
1010
23
12
ND
1.4
1010
21
1.8
2010
25
30
ND
ND
1.6
3.6
2010
23
14
ND
1.1
2010
9.5
ND
3010
18
19
ND
ND
1.4
3.4
3010
23
16
1.3
2
3010
14
1.6
4010
16
22
ND
ND
1.3
3
4010
37
23
ND
1.3
401 0
9
ND
1,1-DCE
1,1,1-TCA
1,1-DCA
1Q10
510
ND
2Q10
570
ND
3010
380
ND
4010
450
,1,1 -TCA
1010
2.7
2010
2.9
3010
3.1
4010
3.4
MW-26D
TCE
1,2-DCE
1,1 -DCA
MW-15SR
TCE
1,2-DCE
1010
NS
NS
NS
1010
150
12
2010
NS
NS
NS
2010
16
ND
3010
NS
NS
NS
3010
210
15
4010
NS
NS
NS
4010
12
1.3
MW-8S
TCE
1,2-DCE
VC
1,1 -DCA
1010
11
26
5
3.4
2010
15
38
9.4
4.7
3010
12
34
7.6
5.1
4010
12
38
9.2
4.5
TCE
1 ,2-DCE
VC
1,1-DCE
1,1,1-TCA
1,1 -DCA
CB
x<^
MW-8D
TCE
1,2-DCE
VC
1,1 -DCA
1010
170
110
31
8.4
5.2
6.2
9.9
XVOOsS^-XN
1010
9.9
22
6.7
4.5
2010
140
77
26
6.4
7.3
5.1
12
S^S^
2010
11
26
8.7
5
3010
83
100
40 J
4.B
ND
5.9
6.6
^$$^
3010
11
27
11 J
5
4010
42 J
61 J
22
3.8
ND
5.3
4.5 J
/
-------
Constituent
TCE
tDCE
vc
1,1-DCA
1Q'
<0
0
Ion (ug/L)
2Q10
<0 5
<0 5
<05
3Q10
11 J
<05
<05
4Q10
<05
<05
<05
-^
Concentration (ug/L)
Constituent
cOCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
FCBs
Con centra
1Q10
33
<1 0
1 0
1 6
<1 0
<0065
Ion (ug/L)
2Q10
27
<1
1 0 J
1 5 NJ
<1 5
NS
3Q10
42
<1
1 0
<1
NS
4Q10
28
1
1
1
1
<005
Constituent
FCE
cDCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
FCB 1242
Concent ration (ug/L)
1Q10
26 J
180
<5 0
14
<5 0
<5 0
<0065
2Q10
30 J
160
<5
15 J
<5
NS
3Q10
35
310
<10
<10
<10
0 097
4Q10
32
180
<5
11
<5
<5
0 109J
Figure 2-5. RHRL 2010 CVOC
Results
Constituent
FCE
cDCE
tDCE
1,1-DCA
1 ,1,1-TCA
PCBs
Concentr;
1Q10
72 J
510
=25
30
=25
=25
<0065
Ion (ug/L)
2Q10
80
400
=25
64 J
<25
<39
NS
3Q 10
69
450
=2
5
=2
=2
N
4Q10
94
380
<10
46
9 4 J
82J
<0 05
Concentration |ug/L)
TCE
cDCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
Concentra
<05
<0 5
<0 5
<0 5
<0 5
<05
Ion (ug/L)
=0~5~~
=0 5
=0 5
=0 5
=0 5
<077
o
0
0
0
0
0
=o
=0
=0
=0
=0
=0
'
This document was developed in co
LEGEND
DUAL-ZONE TRENCH
MONITORING WELL
RECOVERY WELL C
SUMP
GROUNDWATER RECOVERY TRENCH
CAPPED LANDFILL
RICHARDSON HILL ROAD LANDFILL SITE
SIDNEY CENTER, NEW YORK
2010 SITE-RELATED VOLATILE
ORGANIC COMPOUNDS
0 150 300
[jOBRIENOGEnC
-------
0+00
1+00 2+00
3+00
4+00 5+00
6+00
7+00
8+00 9+00
1 0+00 1 1 +00
Figure 3.1 - Richardson Hill Road Landfill extraction trench and
expected capture zone.
Note: This drawing is adapted from Draw ng C-9:
The Ground Water Extraction Trench/Prof le, n the
Record Drawings Richardson Hill Road Landf I Site
Remedial Work Element II Ground Water Extraction
and Treatment.
This document was developed in color. Reproduction in B/W may not represent the data as intended.
FIGURE 16
LEGEND
Design Capture Zone
^| HDPE Pipe
^^ Filter Fabric
F"J=^ Bedrock
| Riser
Til/Bed rock
HI;; Trench Backfill
j Upgradient Abandoned Well Screen
RICHARDSON HILL ROAD LANDFILL SITE
SIDNEY, NEW YORK
EXTRACTION TRENCH
CAPTURE ZONE
DBRIEN C GERE
-------
PAC 1 . POLYMER
ii <~n Mnnn IMTI IMFP PI ATF
2 4 CLARIFIER IPC-1 Gw [
INFLUENT GW FROM ' 1 1 ^7777)
RFrnx/FRY WFI i q r / / // //////
INFLUENT GW FROM r //// IV A
ryTRArrinN TT?rNn i ' * * * ' 1 ^^ 1
Figure 3-2. Process Flow Diagram for
RHRL Treatment System
TANK T-1 I OIL/WATER TREATMENT CLEARWELL
I SEPARATOR UNIT SLUDGE TANK T-5
OIL I OWS-1 T-2/T-3/T-4
I
1
jl SLUDGE TANK
T-6 SUPERNATANT
I J
FLOOR PUMPED TO
SUMP T '
OIL TANK f ] ^~~^
T-10 GRAVITY-THICKENED
SLUDGE
FILTRATE
DEWATERED SOLIDS
PPE COAT N s
TANK T-7 FILTER PRESS
FP-1
i i i i
^=^^=^
~=^-=^ , ,
V J \ J :::::::::::::: :::::::::::::: ^| |
i i
I ) PARbHALL
J L J L ^ J rLUMC
V / V /
""" """ GRANULAR BAG FILTER EFFLUENT
BAG FILTERS AIR STRIPPER BAG FILTERS ACTIVATED CARBON B-5 TANK T-1 4
n 1 /n 9 4<; 1 B 3/B 4 ohDb
B-1/B-2 AS 1 GAC-1/GAC-2
(VESSEL ORDER
CAN BE REVERSED)
P:\742577\CAD\0&M\742577C005.DWG
DISPOSAL D
X2MOT (0^9^
DISCHARGE
FIGURE 1
RICHARDSON HILL ROAD
LANDFILL SITE
GROUNDWATER TREATMENT PLANT
PROCESS SCHEMATIC
^^^^H^3^3^^^3
290 ELWOOD DAVIS ROAD. SUITE 312. LIVERPOOL. N.Y. 13088. PHONE: 315-451-9560
-------
RW-3^_
1762.39 1746.^"
NMW-5 ,
NMW-7
:$-^
MW-
1777.9
NMW-3
* ^
V5=J-
1747.071762.
RW~2 NMW-6
RW-1 ,
1742.3
' '
NMW-4
1763.82
BOX -
& 7B
.
.*>*;
.
GROUNOWATER
TREATMENT BUILDING
ELEV. 1792'
1.01-1.
V-15
STORAGE
SHED
72" Hj
FOf
ES IN 1-4" HOPE SDR-11
E MAIN
Figure 5-1. Groundwater Elevations Richardson
(Arrows indicate direction of gradient)
North Area
-------
iFigure 5-2. Richardson Hill North Area Cone of Depression I
-------
Constituent
TCE
tDCE
vc
1,1-DCA
1Q'
0
Ion (ug/L)
2Q10
<0 5
<0 5
<05
3Q10
11 J
<05
<05
4Q10
<05
<05
<05
-^
Figure 5-3
cDCE Shallow Bedrock Plume
Well I.D.
Constituent
TCE
cDCE
tDCE
1,1-DCA
1,1,1-TCA
FCBs
TMW-02
Concentn
1Q10
72 J
81
<25
<25
<25
Ion (ug/L)
2Q10
87 J
86
<25
^25
<3 9
3Q10
91
140
=05
=5
<5
4Q10
88
83
<25
<25
<25
Constltue
TCE
cDCE
DCE
1,1-DCA
1,1, -TCA
o
We
Co
rr
Concentn
1Q10
5 8 J
75 J
<25J
<25J
<25J
<25J
I.D.
stltuent
Ion (ug/L)
2Q10
6 0 J
59
<25
<25
<25
MW-12DD
3Q10
63
94
<25
<25
<25
26
2Q10
<05
4Q10
6
66
<25
<25
<25
<25
,05
V
Y*a
\ v%
\
. \
\ \
"ฐ)ฐ
Constituent
cOCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
FCBs
Con centra
1Q10
33
<1 0
1 0
1 6
<1 0
Ion (ug/L)
2Q10
27
<1
1 0 J
1 5 NJ
<1 5
NS
3Q10
42
<1
1 0
<1
NS
4Q10
28
1
1
1
1
Constituent
FCE
cDCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
FCB 1242
Concent ration (ug/L)
1Q10
26 J
180
<5 0
14
<5 0
<5 0
2Q10
30 J
160
<5
15 J
<5
NS
3Q10
35
310
<10
<10
<10
4Q10
32
180
<5
11
<5
<5
\
Concentration |ug/L)
Constituent
TCE
cDCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
Concentn
1Q10
<0 5
<0 5
<0 5
<0 5
<0 5
<05
Ion (ug/L)
2Q10
=0 5
=0 5
=0 5
=0 5
=0 5
3Q10
0
0
0
0
0
o
4Q10
=0
=0
=0
=0
=0
=0
Constituent
TCE
cDCE
tDCE
V'C
1 ,1 -DCA
1,1,1-TCA
Concentr;
1Q10
1 7
70
<05
<05
<05
<05
Ion (ug/L)
2Q10
2 1 J
5 0
<05
<05
<05
3Q10
05
05
05
05
4Q10
2
4 9
<05
<05
<05
<05
This document was devel
LEGEND
DUAL-ZONE TRENCH
MONITORING WELL
RECOVERY WELL H
SUMP
GROUNDWATER RECOVERY TRENCH
CAPPED LANDFILL
RICHARDSON HILL ROAD LANDFILL SITE
SIDNEY CENTER, NEW YORK
2010 SITE-RELATED VOLATILE
ORGANIC COMPOUNDS
0 150 300
G
OBRIENEGERE
-------
Constituent
TCE
tDCE
vc
1,1-DCA
1Q'
0
Ion (ug/L)
2Q10
<0 5
<0 5
<05
3Q10
11 J
<05
<05
4Q10
<05
<05
<05
-^
Figure 5-4. RHRL Shallow cis
1,2-DCE Plume
Well I.D.
Constituent
TCE
cDCE
tDCE
1,1-DCA
1,1,1-TCA
FCBs
TMW-02
Concentn
1Q10
72 J
81
=25
=25
=25
Ion (ug/L)
2Q10
87 J
86
=25
=25
<3 9
3Q10
91
140
=05
&
<5
4Q10
88
83
=25
=25
=25
Constltue
TCE
cDCE
DCE
1,1-DCA
1,1, -TCA
o
We
Co
rr
Concentn
1Q10
5 8 J
75 J
<25J
<25J
<25J
<25J
I.D.
stltuent
Ion (ug/L)
2Q10
6 0 J
59
<25
<25
<25
MW-12DD
3Q10
63
94
<25
<25
<25
26
2Q10
<05
4Q10
6
66
<25
<25
<25
<25
,05
V
Y*a
\ v%
\
. \
\ \
"ฐ)ฐ
Constituent
cOCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
FCBs
Con centra
1Q10
33
<1 0
1 0
1 6
<1 0
Ion (ug/L)
2Q10
27
<1
1 0 J
1 5 NJ
<1 5
NS
3Q10
42
<1
1 0
<1
NS
4Q10
28
1
1
1
1
Constituent
FCE
cDCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
FCB 1242
Concent ration (ug/L)
1Q10
26 J
180
<5 0
14
<5 0
<5 0
2Q10
30 J
160
<5
15 J
<5
NS
3Q10
35
310
<10
<10
<10
4Q10
32
180
<5
11
<5
<5
\
Constituent
FCE
cDCE
tDCE
1,1-DCA
1 ,1,1 -TCA
PCBs
\
Concentre
1Q10
72 J
510
=25
30
=25
=25
:lon (ug/L)
2Q10
80
400
<25
64 J
<25
<39
3Q10
69
450
=2
5
=2
=2
N
/
4Q10
94
380
<10
46
9 4 J
82J
<0 05
If
. J
Concentration |ug/L)
x/"
SOUTH
POND
*
1200
Q10 2Q10 3Q10 4Q10
:oncentration |ug/L)
Constituent
TCE
cDCE
tDCE
V'C
1,1-DCA
1,1,1-TCA
Concentn
1Q10
<0 5
<0 5
<0 5
<0 5
<0 5
<05
Ion (ug/L)
2Q10
=0 5
=0 5
=0 5
=0 5
=0 5
3Q10
0
0
0
0
0
o
4Q10
=0
=0
=0
=0
=0
=0
Constituent
TCE
cDCE
tDCE
VC
1,1 ,1-TCA
FCB 1242
Concentration (ug/L)
1Q10
<10
340
<10
160
<10
2Q10
<5J
150
<5
71 J
0 170
3Q10
<10
240
<10
220
<10
4Q10
9 3
210
<5
75
=5
---T
I
Concentration |ug/L)
HERRICK HOLLOW
CREEK
Concentration |ug/L)
-
Concentn
1Q10
12 J
98
70 NJ
<0065
Ion (ug/L)
2Q10
52NJ
3Q10
=2
=2
4Q10
=05
=05
25
0 8
Well I.D.
Constituent
TCE
cDCE
tDCE
VC
1,1-DCA
FCBs
TMW-06
Concentration (ug/L)
1Q10
4 0
5 1
<05
<05
2 NJ
2Q10
35
2 8
<05
<05
Joฐo?o
3Q10
75
17
1 1
<05
3 7
4Q10
4 4
3 1
<05
<05
0 7
/
P
Constituent
TCE
cDCE
DCE
|Well I.Q
Constituent
TCE
cDCE
tDCE
|l,1-DCA
1-TCA
1Q10
73
n
2Q10
<5
NS
3Q10
-.
TMW-07
Concentration (ug/L)
1Q10
54
11
07
<0 5
0 6 NJ
2Q10
73
17
<05
<05
06 NJ
3Q10
10
21
07
<0 5
0 8
4Q10
78
19
=05
<0 5
08
This document was developed in color. Reproduction in B/W may not represent the da
LEGEND
^ DUAL-ZONE TRENCH & RECOVERY WELL CI
ฃ SUMP
GROUNDWATER RECOVERY TRENCH
CAPPED LANDFILL
RICHARDSON HILL ROAD LANDFILL SITE
SIDNEY CENTER, NEW YORK
2010 SITE-RELATED VOLATILE
ORGANIC COMPOUNDS
MONITORING WELL
0 150 300
G
OBRIENEGERE
-------
Treatment System Concretion
Figure 5-5. Treatment system
concretion.
-------
ATTACHMENT B
CVOC Trends in Sidney Landfill Monitoring Wells
-------
Sidney Landfill
MW-1D
VOC Trend Plot
Sampling Event
-------
Sidney Landfill
MW-3S
VOC Trend Plot
Sampling Event
-------
Sidney Landfill
MW-6S
VOC Trend Plot
200
180
m
Sampling Event
-------
Sidney Landfill
MW-6D
VOC Trend Plot
800
700
N
C
tP"
*\J" KW' K*' rt^"* rk*
0 9ป "N 'V 3
Sampling Event
N
C
tP"
-------
Sidney Landfill
MW-8S
VOC Trend Plot
o
m
L.
-------
Sidney Landfill
MW-8D
VOC Trend Plot
c
'b0'
N
c
tP"
Sampling Event
-------
Sidney Landfill
MW-9S
VOC Trend Plot
Sampling Event
-------
Sidney Landfill
MW-15SR
VOC Trend Plot
300
250
Sampling Event
-------
Sidney Landfill
MW-16S
VOC Trend Plot
Sampling Event
-------
Sidney Landfill
MW-19
VOC Trend Plot
Sampling Event
-------
ATTACHMENT C
CVOC Trends in RHRL Monitoring Wells
-------
RH-01
TCE
DCE
VC
-Expon. (DCE)
RH-03
700
TCE
DCE
VC
-Expon. (DCE)
RH-05D
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-l
-------
RH-02
TCE
DCE
VC
-Expon. (DCE)
RH-04D
TCE
DCE
VC
-Expon. (DCE)
RH-06D
r-vr-vooooooootntntntnoooO
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-2
-------
RH-07D
OOOOOOOOOO
TCE
DCE
VC
-Expon. (DCE)
RH-101
OOOOOOOOOO
TCE
DCE
VC
-Expon. (DCE)
RH-12D
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-3
-------
RH-08D
450
TCE
DCE
VC
-Expon. (DCE)
MW-12D
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-4
-------
TMW-02
TCE
DCE
VC
-Expon. (DCE)
TMW-03
TCE
DCE
VC
-Expon. (DCE)
TMW-04
r-vr-vooooooootntntntnoooO'-i
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-5
-------
TMW-05
TCE
DCE
VC
-Expon. (DCE)
TMW-06
OOOOOOOOOO
TCE
DCE
VC
-Expon. (DCE)
TMW-07
250
r-vr-vooooooootntntntnoooO
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-6
-------
RH-04S
TCE
DCE
VC
-Expon. (DCE)
RH-05S
TCE
DCE
VC
-Expon. (DCE)
RH-06S
r-vr-vooooooootntntntnoooo*-!
TCE
DCE
VC
-Expon. (DCE)
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-7
-------
RH-08S
TCE
DCE
VC
-Expon. (DCE)
OOOOOOOOOO
aaaaaaaaaaaaaaa
Attachment C: CVOC Trends in RHRL Monitoring Wells
C-8
-------
ATTACHMENT D
Extraction trench gradients
-------
IN
DG
IN
DG
IN
DG
IN
DG
IN
DG
IN
DG
(71
8
fN
cf
_c
st1
o
t-H
O
fN
cf
_c
------- |