UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION II

DATE: 

### MAY - 7 2012

SUBJECT: Explanation of Significant Differences for the Hooker Hyde Park Superfund Site

FROM: Doug Garbarini,

## Chief9-~~ "-

New York Remediation Brancn

TO : Walter E. Mugdan, Director
Emergency and Remedial Response Division

Attached is an Explanation of Significant Differences (ESD) for the Hooker Hyde Park Landfill Superfund Site.

The Environmental Protection Agency's November 1985 Enforcement Decision Document (EDD, precursor and equivalent to a Record of Decision) for the Hooker Hyde Park Landfill Superfund Site (Site) selected a containment remedy. The goal of the hydraulic containment remedy was to prevent the migration of leachate and contaminated groundwater from the Site through capping

, groundwater collection

, leachate collection

, and treatment of extracted groundwater and leachate.

This Explanation of Significant Differences documents the placement of an institutional control

,

a Declaration of Restrictive Covenants and Environmental Easement

, on the property which

constitutes the former Hyde Park Landfill. The remedy selected in the EDD is a containment remedy. The goal of a containment remedy is to prevent the migration of disposed waste and

leachate along with affected groundwater from a landfill or site. This ESD clarifies that the

selected remedy for the Site in the EDD is a containment remedy and not an aquifer restoration remedy intended to restore the aquifer to its best beneficial use (i.e., a source of drinking water)

.

A letter from the New York State Department of Environmental Conservation concurring with

the ESD is attached.

Please indicate your approval of the ESD by signing below

.

If you have any questions related to the ESD, please call me at extension 4288.

Attachments

Approved :

Walter E. Mugdan, Director Date

E mergency and Remedial Response DivisionPage 1 of 10

INTRODUCTION

In accordance with Section 117(c) of the Comprehens ive Environmental Response, Compensation, and Liability Act of 1980, as amended (CERCLA), 42 U.S. C. ' 9617(c), and Section 300.435(c)(2)(i) of the

National Oil and Hazardous Substances Pollution Con tingency Plan (NCP), if after the United States Environmental Protection Agency (EPA) selects a rem edial action, there is a significant change with respect to that action, an explanation of the signi ficant differences (ESD) and the reasons such chang es were made must be published.

EPA issued an Enforcement Decision Document (EDD, t he equivalent of what is today called a Record of Decision) on November 26, 1985 which documented the selected remedy for the site. The remedy for the Hyde Park Landfill Superfund Site (Site) in the 1985 EDD includes the following specific elements:

• Source control (prototype extraction wells);

• Containment and collection of APL (Aqueous Phase Li quid) and NAPL (Non-Aqueous Phase Liquid) in the overburden of the aquifer;

• Containment and collection of APL and NAPL in the b edrock;

• Treatment of collected APL and NAPL;

• Community Monitoring Program (peripheral monitoring wells for early detection of migration of Site chemicals);

• Intermediate and Deep Formations Study (monitoring wells);

• Industrial Protection Program (remediation of sumps and sealing of manholes);

• Perimeter Capping (clay cap around perimeter of lan dfill);

• Gorge face seeps remediation;

• Bloody Run excavation or capping;

• Final capping and Site closure; and

• 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) Bioaccum ulation Study in Lake Ontario.

This ESD is supported by an Administrative Record f ile. The Administrative Record includes those reports and documents supporting the EDD and this E SD. Reports and documents generated during the investigation and remediation of the Site are inclu ded in the Site file. The Administrative Record a nd other documents are available for public review at the following locations:



### Explanation of Significant Differences

Hooker Hyde Park Landfill Town of Niagara, Niagara County, New York

May 2012Page 2 of 10 U.S. EPA Western NY Public Information Office 86 Exchange Place Buffalo, NY 14204-2026 (716) 551-4410

and

U.S. EPA Region 2 Superfund Records Center 290 Broadway, 18 th Floor New York, New York 10007 (212) 637-4308

This ESD documents the placement of an institutiona l control, a Declaration of Restrictive Covenants and Environmental Easement, on the property which c onstitutes the former Hyde Park Landfill (Landfill). The remedy selected in the EDD is a co ntainment remedy. The goal of a containment remedy is to prevent the migration of disposed wast e and leachate along with affected groundwater from

a landfill or site. This ESD clarifies that the sel ected remedy for the Site in the EDD is a containme nt remedy and not an aquifer restoration remedy intend ed to restore the aquifer to its best beneficial us e (i.e., a source of drinking water).

The change to the selected remedy set forth below i s not considered by EPA and the New York State Department of Environmental Conservation (NYSDEC) t o have fundamentally altered the EDD. The remedy, as modified by this ESD, remains protective of human health and the environment.

SITE HISTORY

The Site, approximately 15 acres in area, is locate d northwest of the City of Niagara Falls in the northwest corner of the Town of Niagara. The neigh borhood surrounding the Site is mixed industrial and residential. The Niagara River, an internation al water body, is located 2000 feet northwest of th e Site in the Niagara Gorge which descends approximat ely 350 feet below the surface of the Landfill.

Hooker Chemical and Plastic Corporation, now Occide ntal Chemical Corporation (OCC), disposed of approximately 80,000 tons of chemical wastes at the Landfill from 1953 to 1975, primarily consisting o f chlorobenzenes. Trichlorophenol (TCP) still bottom s were also disposed; approximately 0.7 - 1.6 tons

of TCDD are believed to have been associated with t hese TCP wastes.

The geology underlying the Site is glacial overburd en overlying Lockport Dolomite, a fractured rock. The overburden is relatively impermeable and approx imately 0 to 30 feet thick. Bloody Run Creek is a drainage channel that flows from the northwest corn er of the Landfill directly north, into storm sewer s discharging to the Niagara Gorge and Niagara River. The bedrock is composed of the following layers: beginning with the Lockport Dolomite, a fractured K arst formation (approximately 100 feet thick); followed by the Rochester Shale (60 feet thick); fo llowed by the Irondequoit/Reynales Limestone formation (Intermediate Formation); and ending with the Queenston Shale (Deeper Formation).

The groundwater in the overburden moves toward the northwest and strongly downward into the bedrock. The groundwater in the bedrock moves down ward and laterally, primarily in a northwesterlyPage 3 of 10

direction toward the Gorge Face, which acts as a na tural drain. Some of the groundwater emerges from the bedrock at the Gorge Face in the form of seeps which flow into the Niagara River.

The contaminants of concern for the Site are TCDD, perchloropentacyclodecane, Aroclor 1248, chloroform, phenol, total organic halogen, benzoic acid, monochlorobenzoic acids (sum of O, P, Misomers), and chlorendic acid.

Chemicals migrate from the Landfill in two phases: (1) chemicals dissolved in the groundwater, called APL and (2) a denser than water phase-like viscous sludge in appearance which migrates under the influence of gravity, called NAPL.

APL and NAPL migrate from the Landfill, creating tw o separate contaminant plumes in the overburden and the bedrock. It is believed that the Bloody Ru n drainage area was contaminated as a result of

infiltration of surface runoff while the Landfill w as still operating, not from the movement of groundwater from below the Landfill. OCC placed a clay cap on the Landfill in 1978.

ENFORCEMENT SUMMARY

EPA filed a lawsuit in 1979 under the authority of the Clean Water Act to require OCC to remediate the Site. EPA, New York State and OCC entered into a S ettlement Agreement in January 1981 which was approved by the United States District Court for th e Western District of New York in April 1982. Unde r the Settlement Agreement, OCC was required to chara cterize the nature and areal and vertical extent of the APL and NAPL plumes in both the overburden and the bedrock. OCC has been implementing the Settlement Agreement under government oversight sin ce 1982. OCC completed the Aquifer Survey (the equivalent of a remedial investigation under the NC P) in 1983. In 1985, after extensive negotiations, EPA, New York State, and OCC agreed on the Requisit e Remedial Technology (RRT) Stipulation which decreed the remedies for cleanup of the Site. EPA issued the EDD (the equivalent of a Record of Decision as mentioned above) in November 1985. The District Court in Buffalo approved the RRT Stipulation in May 1986.

DESCRIPTION OF SIGNIFICANT DIFFERENCES AND THE BASI S FOR THOSE

DIFFERENCES

This ESD has two components. The first component i nvolves an institutional control, which is a nonengineered control to restrict or limit exposure to a hazardous substance. This institutional control is in

the form of a “Declaration of Restrictive Covenants and Environmental Easement” which was placed on the deed to the property on October 7, 2010.

The second component of this ESD is a discussion wh ich clarifies that the remedy selected in the EDD, and approved by the federal court, is a containment remedy and not an aquifer restoration remedy intended to restore the aquifer to its best benefic ial use (i.e., a source of drinking water).Page 4 of 10

COMPONENTS OF THE ESD

INSTITUTIONAL CONTROLS :

The EDD did not specify the implementation of insti tutional controls as a component of the selected remedy. A Declaration of Restrictive Covenants and Environmental Easement was placed on the deed to the Landfill property at the County recording of fice in Niagara County on October 7, 2010. The Grantor (OCC) grants a permanent restrictive covena nt and an environmental easement to the Grantee (Town of Niagara) to provide a right of access over the approximately twenty-one acre property (the “Property”) for purposes of implementing, facilitat ing, and monitoring the remedial action. The covenant/easement also imposes on the Property cert ain use restrictions that will run with the land fo r the purpose of protecting human health and the envi ronment in the future. Figure 1 identifies the

boundaries of the environmental easement.

The following restrictions apply to the use of the Property, run with the land, and are binding on the Grantor: the Property shall not be used in any mann er that would interfere with or adversely affect th e implementation, integrity, or effectiveness of the remedial action performed at the Site, including, b ut not limited to, a) the extraction of on-site ground water, b) any digging, excavation, extraction of materials, construction, or other activity outside the requirements of the remedial action that would disturb the cap placed upon the Landfill at the Sit e, or c) other activity that would disturb or inter fere with any portion of the remedial action for the Sit e enumerated in the RRT Stipulation. The Property also may not be used for residential use. However, the Property may be used for commercial or industrial use as long as long-term engineering con trols are employed and remain effective. Specifically, the operation of the portion of the r emedial action pertaining to the pumping of extract ion wells, operation of the treatment facility, and mai ntenance of the Landfill cap.

In addition to the specific institutional control a t the Site, the Niagara County Department of Health imposes restrictions on the drilling and usage of w ells. These restrictions ensure that drinking-wate r wells are not installed in areas of contaminated gr oundwater, effectively preventing the exposure to s iterelated contaminants through ingestion.

CONTAINMENT REMEDY

The remedy selected in the EDD is a containment rem edy. While EPA expects to return usable ground waters to their beneficial uses wherever practicabl e, within a timeframe that is reasonable given the particular circumstances of the site, when restorat ion of ground water to beneficial uses is not practicable, EPA expects to prevent further migrati on of the plume and, prevent exposure to the contaminated ground water. The goal of the Hyde Park Landfill containment reme dy is to prevent the migration of leachate and contaminated groundwater from the Site through capping, groundwater collection, NAPL collection and treatment of extrac ted groundwater and NAPL. A containment remedy differs from an aquifer restoration remedy which ha s the goal of restoring the aquifer to its best beneficial use. The best beneficial use of this aq uifer is use as drinking water. In order to achiev e this use, concentrations of the contaminants of concern would need to be reduced to their respective Maximum Contaminant Levels (MCLs) established under the Safe Drinking Water Act and/or New York State groundwater and drinking-water standards . Figure 2 presents an aerial view of the bedrock NAPL zone and the area of hydraulic containment res ulting from these actions. Achieving these standards within the containment area is not practi cable and is not an objective of the EDD. The reme dyPage 5 of 10

for the Site will not restore the aquifer to drinki ng-water standards; rather, it is designed to contr ol exposure to contaminants associated with the Site. The NAPL zone in the fractured bedrock, if left uncontrolled, continues to be a source of dissolved constituents to the groundwater. A pump and treat system is the main component of the remedy implemen ted at the Site. This remedy provides engineering controls (pumping wells) to contain the migration of contaminants from the NAPL zone. The selected remedy in the EDD is protective of hum an health and the environment because contaminated groundwater is controlled, collected a nd treated, therefore preventing exposure to the contaminants in the groundwater.

EPA examined various remedial alternatives before s electing a source control and hydraulic control remedy in the EDD. No feasible alternative was cap able of restoring the aquifer to drinking-water standards. As part of the remedy selection process , EPA determined that it was technically impracticable to restore the aquifer. The most eff ective remedy to protect human health and the

environment was to contain and control the NAPL and contaminated groundwater.

Technology does not exist at present which will res tore the aquifer to drinking-water standards. Excavation of the source of contamination is not pr actical because the NAPL is present in fractured bedrock. A significant portion of the NAPL has sor bed to the limestone, effectively creating a reserv oir of contamination for the groundwater. The remedy i mplemented at the Site creates hydraulic control of the affected groundwater.

The remedy as implemented is essentially a source r emoval and containment action. Operation of this remedy was anticipated to be required for a long ti me period as demonstrated by the 35-year operation and maintenance estimate. It is anticipated that t he remedy will not achieve applicable groundwater standards in the foreseeable future due to the pres ence of immobile NAPL in both the overburden and the bedrock. This immobile NAPL will act as a long -term source of chemicals to the groundwater.

A major evaluation and assessment of the remedy was performed from 2000 to 2004. The findings of the assessments and evaluations were presented in t he report entitled "Comprehensive Remedial Characterization Report" dated August 2004. The pr imary conclusions of the Characterization Report were that the Bedrock NAPL Plume Containment System :

i) Satisfies the objective of the RRT hydraulic con tainment;

ii) Maintains the RRT containment objective year-ro und; and

ii) Satisfies the RRT hydraulic containment objecti ve since system start-up in 1993.

The Comprehensive Remedial Characterization Report prepared by OCC in 2004 documents the hydraulic performance of the remedy as implemented at the Site. Several lines of evidence (informatio n derived from different sources or by different tech niques) were selected to evaluate the performance o f the remedy including flow directions from potentiom etric surface maps, flow directions estimated from vertical gradients, the distribution of site-relate d parameters in groundwater, the distribution of ma jor ions, and the relative age of the groundwater and g roundwater flow modeling. Following all these line s of evidence, EPA concluded that the performance obj ectives of the remedy were maintained throughout the year. Based upon these results, the EDD remedy selected for the Site is deemed to be effective in protecting human health and the environment.Page 6 of 10

DESCRIPTION OF REMEDY IMPLEMENTATION

This section provides a summary of the remedial com ponents and the justification for their selection, as identified in the EDD, dated November 1985.

OVERBURDEN REMEDIATION

The remedial approach to address the overburden inc ludes source control, landfill capping, and the

installation of the Overburden Barrier Collection S ystem.

Source Control

The purpose of the source control program is to red uce the contamination migrating downward from the Landfill by removing mobile NAPL remaining in the L andfill. The source control remedial program, as described in the RRT Stipulation, consists of a pro totype system of up to six 36-inch diameter wells

installed in the overburden inside the Landfill.

OCC installed two 36-inch extraction wells in the L andfill in 1990 to collect NAPL. OCC performed pump tests on these wells and also investigated pot ential NAPL source areas within the landfill throug h 1993. However, the large-diameter source control w ells did not collect as much NAPL as was expected. The source control system was redesigned using the 2-inch NAPL extraction well design OCC had successfully utilized at other sites. In 1994, OCC installed four 2-inch source control wells in the Landfill with two-phase flow pumps to facilitate th e pumping of NAPL. Nine monitoring wells were

also installed in the Landfill. One source control well has since been converted to a monitoring well

because of insufficient NAPL collection. The sourc e control program has not yielded significant

amounts of NAPL. EPA believes that most of the NAP L once present in the overburden under the Landfill has either flowed into the bedrock, been c aptured, or remains in pockets or pools that are no t hydraulically connected to the source control wells . In addition, the installation of the final cap o n the Landfill has eliminated the continued production of leachate from rainfall, thereby dramatically reduc ing the hydraulic head and reducing the driving force f or the NAPL.

OCC has recovered and treated more than 300,000 gal lons of NAPL from the Site. NAPL extracted by

source control wells flows into a decanter at the o n-site Storage and Treatment Facility. The total recovered NAPL volume is measured monthly, and the potential amount of NAPL contributed by each well is estimated annually by OCC. The NAPL has ag ed significantly and is extremely viscous. As a result, the volume of NAPL collected from the sourc e control wells has reduced significantly over the past several years and there is no evidence of mobi le NAPL. The source control wells are currently pumped only periodically because of insufficient NA PL volume. EPA believes that the NAPL is in a steady-state condition and not migrating through th e bedrock.

Landfill Cap

The perimeter cap of the Landfill was completed in 1991, and the entire Landfill cap was completed in 1994. The final Landfill cap consisted of the foll owing elements: low-permeability clay; a synthetic membrane; a drainage layer, and topsoil seeded with native vegetation for barrier protection.Page 7 of 10

Overburden Barrier Collection System (OBCS)

The goal of the remedy as it relates to the overbur den is to contain the lateral migration of the NAPL plume and contain the APL plume, to the extent prac ticable. The remedy was implemented by

construction of the Overburden Barrier Collection S ystem (OBCS), a drain around the entire Landfill to contain and collect contaminated groundwater. The OBCS was installed in 1991. Eight well pairs were installed beyond the alignment of an existing drain around the Landfill. One well from each pair is inside the APL plume limits and one well from each pair is outside the APL plume. The inner wells are pumped to create an inward hydraulic gradient. Hyd raulic stabilization was deemed to have occurred in 1994, following one year of continuous dewatering o f the OBCS (i.e., no accumulation of water in the wet wells). Hydraulic monitoring of the OBCS is pe rformed by water-level measurements taken at the eight well pairs. Water-level measurements indicat e that an inward gradient is being achieved, thereb y capturing the contaminated groundwater associated w ith the Site. In addition, NAPL has not been observed in any of the overburden monitoring well l ocations, indicating that the OBCS serves as a barrier impeding NAPL migration.

BEDROCK REMEDIATION

The remedial components implemented for the bedrock consist of the APL Plume Containment System and the NAPL Plume Containment System.

APL Plume Containment System

The Bedrock APL Plume Containment System consists o f two purge wells installed at the Gorge Face in 1994. These wells are pumped to ensure the bedrock groundwater is flowing inward toward the center of the remediated area and to eliminate seepage to the Gorge Face.

The RRT established APL Plume Flux Action Levels ba sed on EPA’s worst-case bioaccumulation assumptions for the following chemicals: TCDD (0.5 gram/year); perchloropentacyclodecane [Mirex] (0.005 lb/day); Aroclor 1248 (0.005 lb/day); and, c hloroform (1.7 lbs/day). These action levels represent concentrations of these contaminants that , if detected entering the river (flux of contamina nts to the river) at or above these concentrations, wou ld require OCC to take additional remedial actions ( e.g., increased pumping, installing additional wells, or other remedial measures) to reduce these contaminant levels. The only parameter detected in 2001 was TCDD. OCC calculated the flux of TCDD to the Niagara River as 7.06 x 10 -5 gram/year, several orders of magnitude below the F lux Action

Level.

NAPL Plume Containment System

The purpose of the NAPL Plume Containment System is to contain, to the extent practicable, APL and NAPL within the NAPL plume in the bedrock, and to m aximize the collection of NAPL from within the bedrock. The NAPL System was designed to contribut e to the elimination of seepage of chemicals at the Gorge Face.

In 1982, OCC performed an investigation which defin ed the extent of the NAPL plume in the bedrock surrounding the Landfill. The NAPL Plume Containme nt System was designed to create an inward hydraulic gradient in the bedrock aquifer surroundi ng the Landfill in order to capture groundwaterPage 8 of 10

contaminated by Site chemicals. The system was des igned and installed in a phased approach in order to achieve proper placement of the extraction wells . The installation of this network consisting of 1 7 extraction wells at the Site was completed in 2001.

The RRT Stipulation required a groundwater monitori ng program with well locations selected along vectors radiating from the center of the Site. The monitoring wells are located inside and outside th e NAPL Plume. The RRT Stipulation stated that an inw ard gradient must be established across the NAPL plume boundary. However, implementation of the vec tor scheme has not proven to be an effective monitoring system. Practical considerations freque ntly impact the selection of well locations. Certa in vectors are located in non-water-bearing rock. Oth er vectors show a flat gradient. To enhance the vector monitoring scheme, with which OCC reports it s Site cleanup progress, local groundwater contour maps were developed.

OCC has implemented the bedrock hydraulic monitorin g program since 1996. For the purpose of monitoring, the bedrock was divided into three sepa rate flow zones: Upper Bedrock, Middle Bedrock and Lower Bedrock. The monitoring program establis hed by the RRT Stipulation was not able to demonstrate an inward hydraulic gradient of the con taminated groundwater. OCC, working with EPA, NYSDEC, and the United States Geological Service, r evised the hydrogeologic framework at the Site and implemented a new groundwater monitoring plan.

OCC revised the Site conceptual model after conduct ing hydrogeological field investigations from 2001 to 2003. These investigations included down-boreho le geophysics as well as water-level measurements in 113 piezometers. The analysis of this data resu lted in a revised hydrogeologic framework consistin g of eleven discrete flow zones separated by aquitard s. These eleven flow zones replaced the Upper, Middle, and Lower Bedrock framework formerly used a t this Site. OCC documented the revised hydrogeologic framework in two documents: Site Characterization Report: Revised Geologic and Hydrogeologic Characterization (February 2002) and Site Characterization Report: Hydrologic
Characterization (February 2003). Figure 2 presents an aerial view of the bedrock NAPL zone and the area of hydraulic containment. The hydraulic conta inment extends vertically through the eleven flow zones to a depth of approximately 160 feet below gr ound surface.

Documentation of Containment – Groundwater Monitori ng

OCC issued the Site Characterization Report: Remedial Characteriza tion Report (“RCR”) in June 2003.

The conclusion set forth in the RCR is that the Bed rock NAPL Plume Containment System satisfies the performance objectives of the RRT (inward gradient) . Although the data for two of the flow zones suggest some uncertainty in the inward gradient, ch emical analyses of the groundwater from these two

zones indicate that site-related contaminants are n ot present in this groundwater. This indicates tha t no migration of contaminants outside of the containmen t system is occurring.

OCC has conducted groundwater monitoring in the eleven flow zones since 2002. The heterogeneous conditions and strong vertical hydraulic gradients in the uppermost flow zones make it difficult to evaluate hydraulic capture using plan-view potentio metric-surface maps. The publication Elements for Effective Management of Operating Pump and Treat Sy stems (US EPA, 2002) states that “accurate interpretation of actual capture is difficult and i s best evaluated using converging lines of evidence .”

OCC used several lines of evidence to demonstrate conta inment, including flow directions interpretedPage 9 of 10

from potentiometric-surface maps for each flow zone , flow directions estimated from vertical gradients

, major ions and the relative age of groundwater, che mical monitoring, and groundwater-flow modeling.

The Performance Monitoring Plan , 2006, sets forth the requirements of the groundwa ter monitoring program. Monitoring consists of the Overburden Mon itoring Program, the Bedrock Monitoring Program, and the Community Monitoring Program. OCC documents that the containment remedy is achieving its performance requirements in the Annual Site Remedial Performance Evaluation Report

.

The Overburden Monitoring Program includes monitori ng the source control wells and the OBCS. The overburden monitoring ensures that there is no late ral migration of NAPL or APL through the

overburden. The data collected in 2010 demonstrate that containment in the overburden is being

achieved.

The Bedrock Monitoring Program includes monitoring the APL Plume Containment System, the NAPL Plume Containment System, and the Bloody Run Creek Monitoring Program. Pursuant to the Bloody Run Creek Monitoring Program OCC samples the creek every five years with the most recent monitoring period being in 2011. The APL and NAPL Plume Containment Systems consist of 19 purge wells which control the lateral migration of APL an d NAPL. Water levels collected quarterly and documented in the quarterly reports as well as the Annual Report demonstrate that containment is being

achieved in the bedrock.

The Community Monitoring Program includes the Gorge Face Program, the APL Flux Monitoring Program, and the Residential Community Monitoring P rogram. The Gorge Face Program includes biannual inspection of the gorge. The APL Flux Monit oring Program ensures that the mass loading of site-related contaminants to the Niagara River is b elow the Flux Action Levels established in the EDD. In this case, the groundwater flux is water lost fr om the interaction between the river and the groundwater aquifer. The EDD requires OCC to calcu late the flux to the river for the four chemicals, namely TCDD, perchloropentacyclodecane, Aroclor 124 8, and chloroform. The calculated fluxes to the Niagara River for these chemicals have consistently been several orders of magnitude below the Flux Action Levels. The Residential Community Program e nsures residents are not exposed to site-related groundwater or soil vapors. The residential monito ring wells have a vertical hydraulic gradient, and soil vapors have not been detected. The results of all the monitoring indicate that the remedy remains protective of human health and the environment.

FIVE-YEAR REVIEW

The NCP provides that remedial actions which result in any hazardous substances, pollutants, or contaminants remaining at the Site above levels tha t allow for unlimited use and unrestricted exposure be reviewed every five years to ensure protection o f human health and the environment. The fourth five-year review for the Site was completed in Sept ember 2011. It evaluated the performance of the various monitoring programs that have been establis hed for the overburden, the bedrock, and the residential community next to the Site to ensure th at the components of the remedy are functioning properly. The five-year review concluded that the remedy as defined by the Site's decision document continues to protect human health and the environme nt.Page 10 of 10

SUPPORT AGENCY COMMENTS

NYSDEC supports the change to the remedy.

AFFIRMATION OF STATUTORY DETERMINATIONS

EPA and NYSDEC believe that the remedy is protectiv e of human health and the environment, and complies with federal and state requirements that a re applicable or relevant and appropriate to this

remedial action.

PUBLIC PARTICIPATION ACTIVITIES

EPA and NYSDEC are making this ESD and supporting i nformation available to the public to inform them of the placement of an institutional control o n the property and to clarify that the selected rem edy for the Site in the EDD is a containment remedy and is not intended to restore the aquifer to drinking

water standards. Should there be any questions reg arding this ESD, please contact:

Gloria M. Sosa Remedial Project Manager

New York Remediation Branch Emergency and Remedial Response Division United States Environmental Protection Agency, Regi on 2

290 Broadway 20 th Floor New York, NY 10007-1866

Telephone: (212) 637-4283

e-mail: sosa.gloria@epa.gov

To be included on the Site mailing list, please con tact:

Michael Basile Community Involvement Coordinator United States Environmental Protection Agency

Western New York Public Information Office

186 Exchange Place Buffalo, NY 14204

Telephone: (716) 551-4410

e-mail: basile.michael@epa.govAttachment 1

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HYDE PARK LANDFILL NAPL AND APL ZONE BOUNDARIES 

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'- HYDE PARK LANDFILL SITE
GLENN SPRINGS HOLDINGS

, INC

. Niagara Falls, New )/0'*Joe Martens

Commissioner 

### New York State Department of Environmental Conservation

Division of Environmental Remediation

Office of the Director

, 12th Floor

625 Broadway, Albany, New York 12233

- 7011

Phone: ( 518 ) 402

- 9706 • Fax: ( 518 ) 402

- 9020
Website: www.dec.ny.gov September 13, 2011

SENT VIA EMAIL ONLY

Mr. Walter E. Mugdan, Director ( m ugdan

. walter@epa.gov ) Emergency and Remedial Response Division

United States Environmental Protection Agency Region 2 290 Broadway, Floor 19 New York, New York 10007

- 1866

RE: Explanation of Significant Differences

Hooker

– Hyde Park Landfill, Site No. 932021 Town of Niagara, Niagara County

New York State Concurrence

Dear Mr. Mugdan:

The New York State Department of Environmental Conservation (Department) and the New York State Department of Health (NYSDOH) have reviewed the Explanation of Significant Differences (ESD) dated July 2011 for the Hooker

– Hyde Park Landfill (Hyde Park). The ESD makes clear that the remedy is not intended to clean up the aquifer to drinking water standards

but to contain the contamination within the aquifer. Groundwater pumping at Hyde Park draws in the groundwater which would otherwise carry contamination to the Niagara River and Lake

Ontario.

A second purpose of the ESD is to document the addition of an institutiona l control. Institutional controls which safeguard the public are now a significant part of our remedial programs. The environmental easement for Hyde Park was filed with the Niagara County Clerk in August 2010. The Department has reviewed the ESD for the H yde Park site, NYS Site N o. 932021, and concurs with this ESD.

Sincerely,

Dale A. Desnoyers

, Director

Division of Environmental Remediation

Attachment

ec: S. Bates, NYSDOH ( smb01@health.state.ny.us ) R. Fedigan, NYSDOH ( rjf01@health.state.ny.us ) M. Forcucci, NYSDOH ( mjf13@health.state.ny.us ) G. Sosa, USEPA ( sosa.gloria@epa.gov )

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