, Five-Year Review Report
Montgomery Township ,Housing Development and Rocky HiUMunicipal Well . I . , . Superfund Sites ..' '
Somerset, ~'ewJersey
Prepared· by:
United States Environmental Protection Agency , ' Region 2
New York, New York
April 2010
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Executive Summary
This is the first Five-Year Review for the Montgomery Township Housing Development , (MTHD) and Rocky Hill Municipal Well (RHMW) Superfund sites. The sites are located in
Somerset County, New Jersey., Both sites are being addressed jointly due to their close proximity and the similarity of contaminants present.
MTHD has two operable units (QUs) as specified in the September 1987 Record of Decision (MTH'D OU1 ROD) and the June 1988'ROD (MTHD OU2 ROD). The MTHD OU1 ROD addressed potential exposure to groundwater contaminants requiring an alternate water ' supply to be installed for residents of the MTHD and sealing of abandoned private wells. EPA issued two RODs for both the MTHDOU2 and RHMW S.ites in June 1988. The June 1988 RODs addressed site-wide groundwater contamination in the underlying aquifer.
In June 1988, one remedy was chosen which addresses the entire groundwater contaminant plume beneath the sites. The most predOIninant site contaminant is Trichloroethene (TCE), both with respect to concentration and areal 'extent. The remedy called for the extraction of contaminated groundwater from the primary source area (hotspot areas where TCE concentrattonswere greater than 100 parts per billion (ppb)) of the contaminant plume I
'followed by on-site treatment imd reinjection oftqe treated water back into the underlying aquifer; connection of remaining affected residences to the public water supply; sealing of private water supplies within the contaminant plume;'and implementation of a groundwater sampling program to monitor the effectiveness of the cleanup. The secondary plumeof groundwater contamination, where TeEconcentrations are less than 100 ppb, :vill be allowed to naturally,attenuate. Volatile Drganic Compound (VOC) concentrations and natural attenuation parameters will be monitored in the secondary plume on a regular basis as part of the long-term groUIldwater sampling program.
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This Five-Year Review found that the OU1 and OU2,remedies are functioning as intended by the decision documents. The OlIl and OU2 remedies are protective ofhuman health and the environment in the short-term, Long-tennprotectiveness will be achieved through treatment and natural attenuation, once the groundwater contaminant levels are below the federal and state cleanup standards. According to the 1988 MTHD and RHMW RODs, theremedial response objective forTCE is 1 ppb, the NJDEP Maximum Contaminant Level (MCL). This level is being used at these sites in place of the Federal MCL of 5 ppb for TCE: In the interim, a classification exception area (CEA) will be established to assure the prevention bf exposure to contaminants until groundwater cleanup standards are achieved.
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Table of Contents
I. Introduction ........................................................................................................... : .............. · ... 1 II. Site Chronology ........................................ : ......................................................... ' ...,' ..... , ........ 2 III. . -Background ....-; .. ~ ......... .'.................... ; ................. : ................ ,' .....................,' .........,' .................3
Site Location and Description.: ............................ , ................................................... 3 Site-Specific Geology ...........~ ......................................:..............................................3
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Hydrogeology ....................... ; ............................. : .................................................... 3 History of Contamination ..... ' ............................................. : .................................... A Initial Response .......................................... : ................................... ,' ..........................4 Basis for Taking Action .................... : .......................................................... ,.: .........4
IV. Remedial Actions ......... , ................................. ~ .. ~: .............................................. : .................. 5 Remedy Selection .......... : ........................................................ ' ............... : ................... 5 Remedy Implementation ............................................................,' .............................8 Operation, Maintenance, and Monitoring ................................................................9
V. Five-Year Review Process .................................................................................................. 10 Administrative Components ..................................... : ............................................. 10 Community Notification and Involvement ............................................................ 10 Document Review ... ' ............................................................................................... 11 Groundwater Data Review ...... : ......... : ................. · .............. ~ .................. ~ ................. 11 .... -,
Site Inspection ... ,' ..... ; ............................................... : ................................................. 13 ' Interviews .............................................................. , ................... : .......................... ;.14
VI. Technical Assessment ......................................................................................................... 14 , VII. Issues, Recommendations and Follow-up Actions ........ , ............................. : ...................... 17
VIII. Protectiveness Statement. ................................... ~ ....................................................... : ....... 17 IX. Next Review .................... ; ......... ~ ................ · ............................................. ~ ........,' ................... 17
,Appendices
Attachment A: . List of Acronyms Attachment B: List of Documents Reviewed Attachment C: Groundwater Contamill'a'nt Trends
Figure 1 Site Location Map
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Five-Year Review Su~mary Form
SITE IDENTIFICATION
Site name (from CERCUS): Montgomery Township Housing Development '(MTHD)
Rocky Hill Municipal Well(RHMW)
EPA ID (from CERCUS): Montgomery Housing Township Development: NJD980654164
Rocky Hill Municipal Well: NJD980654156
NPL status: • Final D Deleted D Other (specify)
Remediation status (choose all that apply): D Under.Construction • Constructed Ii Operating
Multiple OUs?· • YES D NO Construction completion date:
MTHD: 0812412005
RHMW: 08/2412005
Has site been put into reuse? DYES. NO D NIA
REVIEW STATUS
Lead agency: .EPA D State D Tribe D Other Federal Agency ,
Author name: Michelle Granger
A~thor title: Remedial Project Manager
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Author affiliation: EPA
Review period:" MTHD: 0812412005 to 03/3112010
RHMW: 0812412005 to 03/31120 I 0
Date(s) of site inspection: 12/02/2009 ~
Type of review: ,
• Post-SARA o Pre-SARA o NPL-Removal only o Non-NPL Remedial Action Site o NPL StatelTribe-lead
• Policy o Regional Discretio~ ,
'Review number: • 1 (first) D 2 (second) D3 (third) D Other (specify)
Triggering action: D Actual RA Onsite Construction at OU # D Actual RA Start at OU# - o Construction Completion DPrevious Five-Year Review Report • Other (specify) Preliminary CloseOut Report
Triggering action date (from CERCUS): MTHD: 08/24/2005
RHMW: 0812412005
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Does the report includerecommendation(s) and follow-up action(s)? • Is the remedy protective of the environment? • yes D no
yes D no
• ["OU" refers to operable UnIt.].* [Review period should correspond to the actual start and end dates of the Five-Year Review in WasteLAN.]
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Five-Year Review Summary Form (continued)
Issues, Recommendations, and Follow-Up Actions This site has been separated into two operable units (OUs). OUI addressed the provision of an alternate water supply to the residents ofthe Montgomery Township Housing Development. Once the alternate water supply was completed, all residents of the development were offered several opportunities to conned to the alternate water supply. Seventy-nine residents chose to connect and two residents chose not to connectto the alternate water supply. Other than the two residents who kept their private wells, no private wells are in use and the, ingestion of contaminated groundwater has been stopped. ,
The OU2 remedy addresses the contaminated groundwater plume. The remedy inCludes extraction of cohtaminated groundwater through pumping followed by on-site treatment with liquid-phase granular· activated carbon (GAC) adsorption and discharging the treated groundwater into surface water. A groundwater sampling program to monitor the effectiveness of-the cleanup was also impleI1.1ented.. The data trends collected from the effluent of the treated groundwater indicated that the remedy is ,functioning as intended by the decision documents. Areas of the plume exceeding TCE concentrations of 100 ppb are'known as primary source areas .. The secondary plume of groundwater contamination, ' where TCE concentrations are less than 100 ppb, will be allowed to naturally attenuate. VOC concentrations and natural attenuation parameters will be monitored in the secondary plume on a regular basis as part of the long.;term groundwater sampling program.
A CEA application will be submitted to New Jersey Department of Environmental Protection (NJDEP) for State review. Establishnlent ora CEA by N)DEP will assuie that there is no unacceptable future use of the contaminated groundwater in the vicinity of the Sites.
The groundwater remedy is functioning as intended; TCE levels indicate a general downward trend.
Based on groundwater conc~ntrations of site-related chemicals that exceeded conservative screening values presented in {the draft 2002 guidance, "Evaluating the Vapor intrusion into Indoor Air"(USEPA), a vapor intrusion investigation was initiated. Three rounds of sub-slab and/or indoor VOC analyses were conducted for the site. To ensure protectiveness, ongoing sampling and monitoring of both sub-slab and indoor VOCs was determined to be necessary; ,
Other Comments on Operation, Maintenance, Monitoring, 'and Institutional Controls
See above regarding CEA establishment. Long-term groundwater monitoring is ongoing and will continue. Routine operation and maintenance activiti.es and adjustments to these activities will be made on an ongoing basis as needed.' ,
Issues, Recommendations, and Follow-up Actions ,
Oversight,' Recommendations & Issue Party AffectsMilestone i Follow-up Actions AgencyResponsible Protectiveness?Date
: (YIN) Current I Future
yCEA To l}e established NJDEP 2012NJDEP N I !
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,Protectiveness Statement The remedies at the Montgomery HousingTownship Development and Rocky Hill Municipal ,Well Superfund sites currently protect human health and the environment. The remedies are protective in the short-term. In order for the remedies to be protective in the long-term, the following actions'need to be taken to ensure protectiveness:
• Continued groundwater monitoring until groundwater contaminant levels are below the Federal and State Cleanup Standards.
• A CEA must be established by NJDEP. ;
" • Periodic Soil Vapor Intrusion monit()ring will be performed.
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I. Introduction
, The purpose of a Five-Year Review is to detennine whethepthe remedies at a site are protective of human health and the environment. The methods, findings, and· conclusions ·of reviews are documented in Five-Year Review reports. In addition, Five-Year Review reports identify issues found during the review, if~my, and identify recommendations to address them. .
Thisreview was conducted pursuant to Section 121(c) oftheC~mprehensive Environmental . Response, Compensation, and Liability Act (CERCLA), as amended, 42 U.S.C. Section 9601, et seq.,and 40 C.F.R. 300.430(f)(4)(ii) and in accordance with the Comprehensive Five-Year Review Guidance, OSWER Directive 9355.7-03B-P (June 2001).
EPA, Region: 2, conducted this Five-Year Review of the remedies implemented at the· Montg9mery Housing Township Development and Rocky Hill Municipal Well sites in Somerset County, New Jersey. This Five-Year Review was conduCted by Michelle Granger, Remedial Project ManageL(RPM). This report documents the Tesults of the review:
This is the first Five-Year Review for the Montgomery Housing Township Develppment and Rocky Hill Ml:micipalWell sites. The triggering action for this policy review was the completion of Superfund Preliminary Close Out Report (PCOR), dated August 2005 for bQth. .
sites. A Five-Year Review is being conducted due to the fact that hazardous substances, pollutants, or contaminants Will not remain at the sites above levels that allow for unlimited use and unrestricted exposure but the remedy will take more than five years to complete.
While the sites constitute two separate National Priorities List (NPL) sites, the sites are being addressed jointly due to their close proximity and the similarity of contaminants present. There is one groundwater remedy that addresses both sites. Therefore, this five-year review addresses both sites.
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II. Site Chronology ! ~
Table 1, belOw, summarizes site-related events from discovery to present operation and, maintenance activities:
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Table 1: Chronology of Site Events J
Eventf Activity Date
RHMW Wells .1. and 2 'constructed 1936
RHMW Well 1 abandoned and sealed between 1976 and 1978
RHMW Well 2 closed due to elevated TCE concentrations in groundwater November 1979'
Elizabeth Water Company installed water lines within Montgomery Township and residents were advised not to use well water
March 1981
RHMW Well 2 closed for a second time. ,
January 1982
After the Installation of2air stripping units by the borough of Rocky Hill for RHMW Well 2 the well reopened as a potable water source
July 1983
MTHDand RHMW Sites ~ere included on the National Priorities List September 1983
NJDEP placed a restriction on future well drilling for water supply wells in the area January 1986
NJDEP entered into a Cooperative Agreement with EPA to perform a'n RIfFS for the RHMW Site
1984
MTHD OUI ROD issued Septerribe! 1987
NJDEP issued a RI Report April 1988
MT,HD and RHMW OU2 RODs issued June 1988
Cost Recovery litigation bet~een thePRPs and EPA 1991 - 2004
The lead for the RD and implementation of the remedy for the Site was transferred from NJDEP to EPA
December 1996 ,
EP A performed a limited groundwater investigation to determine current extent of )
the groundwater plume , ' . JailUary 1998 :
EPA entered into an interagency agreement with USACE for the completion of RD work
August 1999
RD field work resumed February 2001
Additional rounds of gw sampling conducted 7002
Completion ofRD activities August 2003
RA WP, approved January 2004
Construction activities of the recovery wells, a number of additional monitoring wells and GWTF #1 and #2 completed
January 2005
14 day pump test completed January 25, 200S,
Final inspection of 2 gw pump and treat plants conducted february 1,2005
ESD for OU2 issued August 2005
Preliminary Site Closeout Report for MTHD and RHMW August 2005
Final Operation and Maintenance Manual for GWTF #1 andGWTF #2 January 2006
Long-Term Groundwater Sampling Program (
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III. Background
Site Location 'and Description:
The RHMW/MTHD Superfund Sites are located adjacent to one another in the Borough of Rocky Hill and in Montgomery Township, respectively, west of the Millstone River in the southern part of Somerset County, New Jersey. The RHMW site is located on approximately two acres of land situated east of New 'Jersey State Route 206 and directly south of Route 518. The MTHD site includes 71 one-acre residential lots located in Montgomery Township and six additional residences nearby. The homes'are on Montgomery Road, Sycamore Lane, Robin Drive, Oxford Circle, and Cleveland-Circ)e, and are east of New Jersey Route 206 and north of Route 518. Properties along Montgomery Road,the northern border of the MTDH Site are wooded, residential or agricultural lots. The area surrounding the sites consists of wooded areas, a shopping plaza, parking lot, and residential and commercial development.
Groundwater at both sites is contaminated with volatile organic compounds (VOCs) and TCE in particular. Although the RHMW and MTHD Sites were listed(separately on the National Priorities List (NPL)in 1983, they are being addressed jointlydue to similarity of contaminants and their close proximity to each other.
See Figure 1 for the Sites ~ocation Map.
Site-Specific Geology:
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The fractured siltstones, shales, and sandstones of the Passaic Fomiation underlie the Sites . . Mapping by Parker and Houghton (1990) indicates thatthe Passaic Formation in the vicinity of the sites has undergone little deformation and that bedding strikes generally north, 65 degrees' east (N65E) and dips to the northwest at about 17 degrees towards the Hopewell Fault located, about 5 miles northwest of the sites. A diabase sill outcrops to the south of the sites and forms the "Rocky Hill." Parker and Houghton (1990) also observed some steeply dipping joints in the study area ranging in strike from subpara:llel to bedding to NUE. Unconformibly overlying the Passaic Formation are unconsolidated s~diments comprised mainly of Quaternary weathered shale and the older Pliocerie Pennsauken Formation. The sediments range in thickness from 3 feet to morethat15 'feet at the sites. They are underlain by the much older bedrock of the Triassic Age Passaic Formation (NJDEP 2002). Weathered bedrock extends as deep as 30 feet below ground surface (bgs) beneath the sites.
Hydrogeology:
Groundwater flow is perpendicular to the potentiometric lines, from the highest elevations toward the lowest elevations. In both surfaces the cone of depression created by pumping at the RHMW is evident to the southwest of the well. To, the north of the RHMW, the priiTiary
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, direction of groundwater flow at the sites is to the east towards the. Millstone River and north towards Beden Brook. Finally, the potentiometric surfaces show a groundwater flow divide, trending northeastlsouthwest,trenching along aline between former monitoring wells MW16/MW--16D and MW-04D.'
History of Contamination:
RHMW wells numbered 1 and 2 were constructed in 1936. These two wells provided a source of potable water to the Borough of Rocky Hill. Well.number 1 was abandoned and sealed between 1976 and .1978. In 1978, a study by Rutgers University on the RHMW revealed trichloroethene (TCE) contamination in groundwater at levels of approximately 25 ·parts per billion (ppb). Continued testing of this well by the Borough' of Rocky Hill from 1978 to 1983 indicated that the TCE concentration ranged from about 50 ppb to, 200, ppb. Due to the elevated levels ofTCE in groundwater, well number 2 was closed in November 1979. Levels ofTCE in the well. water eventually declined, and the well was subsequently reopened. Levels ofTCE, however, increased, and the well was closed for a second time in January 1982. During the shutdown of well number 2, the Borough of Rocky .Hill obtained potable
. water from the Elizabethtown Water Company. After the installation of two air-stripping units , by the Borough for well number 2, thewell reopened asa potable source ofwater in July
1983, lan~ has been operating since.
Initial Response:
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Discovery of contamination in the Rocky Hill Municipal Well led the New Jersey Department of Enyironmental Protection (NJDEP) to sample the residential wells of the neighboring Montgomery Township Housing Development (MTHD). The sample results detected the presence ofTCE in domestic wells of residences within the MTHD. In March 1981, the' Elizabethtown Water Company began to install water supply lines in the MTHD, and residents were advised not to use well water. Alternate water supply lines were subsequently connected to all residential properties in the MTHD with the exception of three residences where the property owners declined to us~ water supplied by Elizabethtown Water'Company.
In 1983, the sites were included on the National Priorities List. In 1984, NJDEP entered into a Cooperative Agreement with EPA under which it performed the remedial investigation and feasibility study' (RIIFS) for the RHMW and MTHD Sites.
In January 1986, NJDEP Division 'of Water Resources placed a restriction ,on future \Yell drilling for water supply in the ,area.
Basis for Taking' Action: ) ,
In 1985, NJDEP began conducting theRI/FS for the sites. The RI included gr;ound~ater, surface water and stream sediment, septic tank, soil, and air sampling,. In April 1988, NJDEP issued a remedial investigation (RI) report which identified the nature and extent of the
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groundwater contamination and conCluded that the source of groundwater contamination to the RHMW and MTHD Sites was at or in the vicinity of the Princeton Gamma-Tech, Inc.
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facility located on Route 518 in Montgomery Township. In the 1970's, PGT used a septic system to dispose of sanitary and lab sink waste: Septic tank samples at this property identified the presence ofTCE at levels as high as 5,000 ppb. The tank was tested by NJDEP and remove~ from the property following a spill in 1980.
The RVFS reported results for 28 soil samples taken at the property, none of which showed ,TCE contamination.
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Concentrations ofTCE found in the major source area of groundwater contamination in the Princeton Gamma-Tech, Inc. property well (well PGTMW-l) had decreased from 5,000 ppb in the 1980s to 1,800 ppb of TCE by 1992 . .The maximum concentration of TCE in the well continued to decline over the next six years to 320 ppb. The above information indicates that the past discharge was the source of contamination found in the shallow groundwater. Following the source removal performed under the guidance ofNJDEP, TCE concentrations in the groundwater have decreased significantly.
PGT was identified as the major source ofTCE contamination during the RVFS because of the documented use and disposal ofTCE on-site, the relatively high concentrations ofTCE detected' in groundwater samples at the property, the detection of TCE)n samples from both the shallow and deep bedrock monitoring wells, the observation of a vertical downward hydraulic gradient at the property, and the groundwater flow pattern. ' Exposure path~ays considered in the risk assessment include inhalation, ingestion, and dermal adsorption.
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IV. Remedial Actions
The MTHD and RHMW sites were divided into two operable units (OUs): OUI addressed the private potable well contamination in the MTHD by providing for public water supply to those residents whose wells were threatened or contaminated and permanently sealing those' private wells, and OU2 addressed the entire groundwater contaminant plume beneath the sites.
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OU~ RemedySelection
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Due to concern over groundwater contamination in Rocky Hill, NJDEP conducted initial sampling of commercial and domestic wells in MontgomeryTownship from December 1979 to January 1980. Results indicated that approximately half of the private wells in the development were contamin.ated with TCE ..while the remaining half was threatened.' On August 21, 1980 Montgomery Township passed an ordinance authorizing the water line , extensions into the development." In March 1981, Elizabeth'Water Company mains were ,installed in a portion of Montgomery Township, and residents were advised not to 'use well
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water.
.( . Following completion of the RIfFS, aRecord of Decision (ROD) was signed on September 1987 that called for an alternate water supply to be installed for residents of the MTHD by providing, waterline extensions and connections and sealing of abandoned private wells. Extension of water mains and connection of residents to the Elizabeth Water Company' was completed in 1989 and 1990.
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OU2 Remedy Selection '
EPA issued RODs forboth the MTHD and-RHMW Sites in' June 1988. Both sites are being addressed jointly due to their close proximity and the similarity of contaminants present. One remedy was chosen which addresses the entire groundwater contaminant plume beneath the sites. The remedy called for the extraction of cohtaminated groundwater from the primary source areas, (whereTCE is approximately greater than '1 00 ppb) within the con~aminant plume followed by on-site treatment and reinjection of the treated water back into the underlying aquifer; connection of any remaining affected residences to the public water supply; sealing of private water supplies within the contaminant plume; and implementation
. of a groundwater sampling program to monitor the effectiveness of the cleanup., The secondary plume of groundwater contamination, where TCE concentrations are less than 100 , ug/l, will be allowed to naturally attenuate. VOC concentrations and natural attenuation parameters will be monitored in the. secondary plume on a regular basis as part of the longterm groundwater sampling program. r'
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In 1988, the New Jersey Department of Environmental Protection began to design the remedy for the sites employing Camp,:Dresser, & McKee (CDM) as it's contractor. Initial remedial design (RD) work iricludedconstruction and sampling or'new monitoring wells, and sampling of , existing monitoring wells. During the RD it was found that contamination had been detected in a downgradient well (MW -19), located on the east side of the Millstone River, th~t did not
\ . , previously contain detectable le:vels ofTCE in previous sampl'irigevents. This indicated thatthe contaminated groundwater plume was migrating beyond previously estimated contamination boundaries. The RD also indicated the concentrations ofTCE found in a major source area of groundwater contamination in the Princeton Gamma-Tech, Inc. property well (well PGTMW-1) had decreased from 5,000 ppb in the 1980s to 1,800 ppb ofTCE by 1992. The maximum concentration ofTCE in the well continued to decline over the next six years to 320 ppb.
In 1991, cost recoverylitigation was initiated between the Potentially Responsible Parties {PRPs} and EPA. In 1994, the PRPs.indicated-an interest in negotiating the implementation of the remedy and the RDcontract between,NJDEP and CDM was suspended. During this period of negotiations, another potential source of contamination was identified. Separate negotiations beganiri 1995 between EPAand a prior operator and current owner of the former Fifth Dimension Facility to investigate this other potential source of contamination. Negotiations were unsuccessful and EPA conducted an inyestigation at the property. The results of the '
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investigation at the Fonner Fifth Dimension Facility showed that it was a source ofTCE groundwater contamination with a maximum concentration of 8~ ppb ofTCE in groundwater.
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In December of 1996, the lead for the remedial design and implementation of the remedy for the sites was transferred from NJDEP to EPA.'
In January 1998 EPA perfonned a limited groundwater sampling event to detennine the,current vertical ahd horizontal extent of the groundwater contaminant plume. Theanalytical results showed that TeE contamination concentrations, while still significantly elevated above the selected site cleanup standard of 1 ppb, had further decreased. TCE was detected in the groundwater at the sites at levels ranging from non-detect to a high of 320ppb.
EPA restarted the RD work following the conclusion of unsuccessful settlement negotiations between the parties in 1999. In August.1999, EPA entered into an interagency agreement with the United States Anny Corps of Engineers (USACE) for the completion ofRD work at the sjtes .. USACE contracted with CDM Federal Programs Corporation to complete the RD.
In 2001, EPA re-evaluated the remedy selected in the 1988 ROD in order.to assure its technical merits and confonnance with all current Agency guidance and policy. This re-evaluation included the review of all relevant guidance and policy generated sinye the ROD to determine if post-ROD policy and guidance would have an impact on the planned cleanup at the Site. This review indicated that the selected remedy complies with all current, relevant guidance and policy, is protective ofhuman health and the environment and remains the appropriate remedy to address contamination at the sites.
CDM resumed RD field work in February 2001. As part of this work, 20 bedrock monitoring wells were re-constructed to further refine groundwater sample collection. Following bedrock monitoring well reconstruction, additional rounds of groundwater sampling were conducted in 2002. The infonnation obtained from these sampling events suggests that concentrations ofTCE decreased in the aquifer between 1998 and 2002. Although levels have decreased from those found if! previous sampling events, TCE contamination in groundwater remains at levels several" hundred times greater than the selected site cleanup~tandard of 1 ppb.
The remedial design for the groundwater pump and treatment systems called for pumping the contaminated groundwater from two areas of the contaminant plume containing concentrations of TCE higher than 100 ppb. Areas of the plume exceeding TCE concentrations of 100 ppb are known as primary source areas. The remedial design called for the treatment of groundwater extracted from the primary source areas with Granular Activated Carbon (GAC) and discharge of treated water ~o a surface water body; The treatment using GAC and discharge to surface water, called for in the design represented a minor modification to the remedy selected in the 1988 ROD. The ROD specified treatment by air stripping and reinjection of the treated water back. into the underlying aquifer.
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Air stripping and GAC, adsorption are both recognized by EPA as best available technologies (BATs) and presumptive ex-situ treatment technologies for VOC removal from water. A
, technical evaluation of these two treatment options supported the use of GAC adsorption based upon cost benefit analysis and broader operational flexibility and control (e.g., hydraulic operating range, effective treatment range according to influent water quality),
Given the reduced size of the primary TCE plume and the simpii:5ed and less costly ope;ation of the surface discharge o(treated water, it wasdetermined that injection of treated water was not required to provide hydraulic control and to flush contaminants from the aquifer. Furthermore, ' injection wells are prone to biological and inorganic fouling as
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a result of differences in water chemistry between the groundwater effluent and the aquifer. Chemical and, physical treatment of injection wells is typically required on a routine basis in order to maintain adequate hydraulic capacity for reinjection. Even with such treatment, hydraulic capacity generally decreases with' time, eventually resulting in the need to replace injection wells,. Given these considerations, surface water discharge via connection to the existing storm water' sewers was chosen as the
'preferred option for effluent disposal. The change in the treatment and discharge components to the remedy were documented in an Explanation of Significant Differences (ESD) issued by EPA in August 2005. NJDEP ~as consulted and approved the surface discharge oftreated water.
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'OUI Remedy Implementation
Following completion of the RVFS, a Record of Decision (ROD) was signed 01). September 19?7 that called for an alternate water supply to be;installed for residents of the MTHD and sealing of abandoned private wells. Extension of water mains and connection of residents to ' use water supplied by the Elizabeth Water Company was completed in 1989 and 1990.
, Pursuant to the OU 1 ROD, the alternate water supply lines were, installed and residential properties in the MTHD received individual connections with the exception of two residences,
. where the property owners refused to use water supplied by Elizabetp Water Company.
OU2 Remedy Implementation
Pursuant to the ROD for OU2, the remaining three residents of the MTHD were connected to the public ,water supply in1990.
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Following 'completionof remedial design activities in August 2003, tne USACE awarded a contract for the con'struction and operation oftwo groundwater treatment systems, to Cape :Environmental. The contract award was followed by the submittal of the remedi~l actio~ work plan which was approved in January of 2004. .
Construction activities for the remedy began on March 15,' 2004. Construction activities included the installation of eight recovery wells and the construction of two treatment plants.
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One of the targeted remediation zones is the primary source area located on the property at 1377 Route 206.' Ground Water TreatmentFacility #1 (GWTF #1) and its six recovery wells were constructed at this location. The targeted remediation zone for this area of the plume extends vertically from 50 feet to 200 feet below ground surface and is enclosed horizontally by the existing 100 ppb TCE isoconcentration contour. The objective of the capture zone was to achieve capture of the targeted remediation zone. GWTF #1 was constructed at 1377 Route 206 , and three pairs of recovery wells were installed within the primary source area located under tJ?at property. The paired recovery wells (i.e., shallow and deep) for GWTF #1 were designedto avoid creating a conduit for vertical migratiofi~of contami,nation from the shallow bedrock to the deeper bedrock., Two of the three pairs of wells generated adequate amounts of water that produced a flow rate of 56 gallons per minute into the treatment plant. Thethird pair, recovery well 3S and recovery well 3D, were not productive and were converted into monitoring wells.
A second smaller primary source area is located to the south underlying the Princeton Gamma Tech property near the intersection of Routes 206 and 514. Two recovery wells were installed on this property. These two wells were constructed to extract groundwater within the primary source area underlyingthis property that extends vertically between 25 to 100 feet below ground surface within the weathered bedrock and shallow bedrock aquifer. These two recovery.wells pump a total of six gallons per minute of extracted groundwater into a portable trailer-mounted treatment unit known as Groundwater Treatment Facility #2 (GWTF #2). This treatment unit, similar to GWTF #1, uses GAC to treat extracted groundwater and discharges treate~ water to a surface water body via a storm sewer.
Co'hstruction of the recovery wells, a number of additional monitoring wells, and GWTF #1 and #2 was completed on January 11,2005.
Performance and startup testing on the groundwater treatment systems began on January 11, 2005 and consisted of a 14-day pump test. The 14-day pump test was satisfactorily completed on January 25,2005. A final inspection of the two groundwater pump and treatment plants was conducted by EPA, NJDEP, and USACE on February 1,2005. The two treatment plants have beeri running continuously since January 2005. GWTF #1 is currently pumping contaminated water from the aquifer at its designed flow rate of 56 gallons per minute. GWTF #2, located on the Princeton Gamma Tech property, is currently pumping at its designed flow rate of 6 gallons per minute.
A Final Operations and Maintenance Manual was submitted to EPA on July 29,'2005, reviewed by EPA and NJDEP, and approved in January 2006.
Operation, Maintenance, and Monitoring:
GWTF #1 and GWTF #2 continue to operate at a combined fl0w of62 gallons per minute (gpm) extracting groundwater from the two primary source areas. Over one 'hundred million gallons of contaminated groundwater have been p~mped from the primary source areas and have been
. treated and discharged to date. Cape Environmental, through a contract with the USACE,
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provides maintenance and groundwat~r monitoring. GWTF #li& expected to pump groundwater , from the primary source area .located at 1377 Route 206 for 25 years before attaining the .
groundwater cleanup goal of 1 ppb TCE within the capture zone. It is estimated that it will take 10 to 15 years of pumping from GWTF #2 to achieve the cleanup goal of 1 ppb TCE in primary source area located at the Princeton Gamma Tech property. .
The operation ofthe GWTF #1 and GWTF #2 systems should effectively remove site related contaminants from the primary source areas in the aquifer.' The secondary plume of groundwater contamination, where TCE concentrations are less than 100 ppb, will be aqowed to naturally
. attenuate. VOC concentrations and natural attenuation parameters are being monitored in the I ' ,
secondary plume on a regular basis as part of the long-term groundwater sampling program. I
Basedon groundwater concentratioris of site-related chemicals that exceeded conservative' screening values presented in the draft 2002 guidance, "Evaluating the Vapor intrusion into Indoor Air"(USEPA), a vapor intrusion investigation was initiated. Three rounds 'of sub-slab and/or indoor VOC analyses were conducted for the sites (see Section VI Technical Assessment,
, :/
Question B for details on the vapor intrusion investigation conducted). To ensure protectiveness, ongoing sampling and monitoring of both sub-slab and indoor VOCs was determined to be necessary for the commercial stores lo'catedwithin the shopping center.
A Classification Exception Area will be established by NJDEP within the area of groundwater contamination to regulate the installation of additional wells within the contaminated groundwater plume.
V. Five-Year Review Process '
Administrative Components:
This is the first Five-Year Review for the MHTD and RHMW Superfund sites. The triggering action for this policy review was the completion of Superfund PCOR, dated August 2005 for the MTHD andRHMW sites. Upon completion of remedial activities, hazardous substances will not remain above levels that would prevent unlimited use with unrestricted exposure. However, it.is the policy of EPA to conduct Five-Year Reviews of sites where remedial activities, including monitoring, will continue for more than five years.'
For this Five-Year Review, the review team consisted of Michelle Granger (EPA - RPM), Robert Alvey (EPA - Hydrogeologist), Michael Sivak and Urszula Filipowicz (EPA -Human Health Risk Assessors). \ ,
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Community Notification and Involvement:
EPA published a notice in the Princeton Packet, a local/regional newspaper, on December 24, 2009, notifying the community of the initiation of the five-year review process. Thenotice indicated that EPA would be conducting a Five-Year Review of the remedies for the sites to ~nsure that the implemented remedies remain protective ofpublic health and the environment and are functioning as designed: It also indicated that upon completion of the five-year review, results of the review would be made available at the designated site repositories. The notice included the RPM's address and telephone number for questions related to the five-year review process or the MTHD and RHMW sites. The RPM has not been notified of any additional concerns with the remedy:
In addition,the notice indicated that once the Five-Year Review is completed, the results' would be made available to the public at the following locations: ..
Mary Jacobs Library 64 Washington Street Rocky Hill, New Jersey 08553 .. (609) 924-7073
U.S. EPA Records Center, Region II 290 Broadway, 18th Floor. New York, New York 10007-1866 (212) 637-3261
_Michelle Granger of EP A has discussed the ongoing groundwater remedy with the five year .review team, the USACOE, the Montgomery Township Health Officer, and the Borough of Rocky Hill Engineer. There were no significant issues or concerns raised about the prot~ctiveness of the remedies in place at the sites.
Document Review:
The documents, data, and information which were reviewed in completing this five-year review are identified in Attachment B. Attachment A provides a listing of acronyms u,sed in this· document.
Groundwater Data Review:
This Five-Year Review focuses on analyzing groundwater data collected since the inception of pumping both treatment plants in 2005. Quarterly groundwater sampling has been conducted since 2005. This Five Year Review covers groundwater sampling data from March 2005 . through September 2009. The groundwater samples were analyzed for target compound list (TCL) VOCs. A summary of groundwater contaminant trends for TCE and peE are provided in Attachment C.
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I
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Between March2005 and September 2009, groundwater sampling results indicate the following: I '
GWTF#1 Primary Source Area Data " I
Six groundwater monitoring wells are located within the primary source area capture zone associated with GWTF#I. TCE and PCE have been detected at levels that exceeded the State and Federal Groundwater Standards (MCLs). The maximum concentrations detected ofTCE and PCE in the most recent sampling event (September 2009) were 57 ppb and 120 ppb at MW17, respectively.
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Groundwater monitoring results indicate decreasing trends in TCE within the capture zone for GWTF#L A review of influent sample results for GWTF #1 confirms a significant decline hi TCE levels from approximately 80 ppb in 2005 to under 20 ppb in 2009. peE levels, however, initially declined between 2005 through 2008 from roughly 40 ppb to 5 ppb, but have shown a recent increasing trend during 2009 to "over 30 ppb. Review ofmonitoring well data indicates overall general declines in levels ofTCE with few exceptions. The sampling results from MW17 reveal increasing levels ofPCE to 120 ppb as of July 2009 surpassing TCE (approximately 60 ppb) as the prime constituent. The monitoring well is located immediately downgradient from the Montgomery Shopping Center complex building, but is within thecapture~one of GWTF #
, 1. EPA will continue to regularly monitor the concentrations of PCE in this area, if concentrations continue to increase further evaluation may be warranted. ,
GWTF#2 Primary Source Area Data
Six groundwater monitoring wells are located within the primary source area capture zone associated with GWTF#2. TCE and PCE have been detected at levels that exceeded the State and Federal groundwate~ Standards (MCLs). -The maximum concentration detected ofTCE and PCE in the most recent sampling event (September 2009) were'270 ppb a,nd 4 ppb (PGT-MW-Ol and MW-07S), respectively. I / '
'Groundwater monitoring results indicate decreasing trends inTCE and PCE within the capture zone for GWTF#2. A review of influent sample results from GWTF # 2'confinns a gdneral downward trend ofTCE since initiation of extraction pumping, with the exception of one well. tCE influent to the treatment facility has declined from slightly above 100 ppb in 2005 to below 50 ppb in 2009. However, TCE levels in: PGT-MW-Ol have increased from 240 ppb in March 2005 up t0480 ppb in 2006 and generally decreased to 270 ppb in September 2009. Sampling results for PCE indicate that it is not aconcem at GWTF # 2. PCE levels into the treatment
_facility have beenat or below 1 ppb since 2007 and have not e~ceeded 3 ppb since inception of. pumpmg.
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Former Fifth Dimension Data
Two groundwater monitoring wells are located in the vicinity of the Former Fifth Dimension
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facility. The maximum concentrations ofTCE and PCE in the most recent sampling event (September 2009) were 14 ppb and 0.9 ppb (FD-OID andFD-~ID), respectively.
TCE and PCE have been detected at levels that exceeded the State~nd Federal groundwater Standards. Groundwater monitoring results indicate decreasing trends il) TCE. and PCE. A review of sample results for monitoring wells FD-Ol confirms a signifi<;ant decline in TCE levels from approximately 13 ppb in 2006 t08 ppb in 2009. TCE levels in FD-OID have also declined since December 2006 from approximately 21 ugll to 14ugll. PCE levels in FD-O 1 declined between 2006 through 2009 from roughly 5 ppb to 0.9 ppb. PCE levels in FD.,.OID did not exceed State and Federal groundwater Standards.
Secondary Plume Data \
The secondary plume of groundwater coptamination, where TCE concentrations are less than 100 ppb, will be allowed to naturally attenuate. All areas outside of the primary source areas are included inthe secondary plume (see Figure 1). .
Thirty-seven groundwater monitoring wells are located within the secondary plume. A rev;ew of ' , groundwater monitoring data in the secondary plume confirms a general downward trend ofTCE and PCE in the 37wells. The maximum concentration detectedofTCE and peE in the most rec~nt sampling event (September 2009) were 110 ppb and 14 ppb (MW -20S and MW -23 I), respectively. '
Downgradient well MW-19, located on the east side of the Millstone River, had TCEat approximately 27 ppb in October 2004. However, since December 2007, fevels have decreased significantly to below the selec,ted site cleanup standard of 1 ppb, thereby indicating that the
, contaminated groundwater plume has not migrated beyond previously estimated contamination boundaries.
Based on the finding of this Five-Year Review, continued groundwater monitoring is warranted. The long-term groundwater monitoring program that has been implemeJlted thus far will ,continue 'to be implemented. The sampling schedule will include regular monitoring of all wells in' the primary source areas and secondary plume for VOCs.
Site Inspection:
An inspection of the MTHD and RHMW sites was conducted on December 2,2009. The' following parties were in attendance:
Michelle Granger, EPA Region II Project Manager, , Michael Sivak, EPA Region II Risk Assessor Urszula Filipowicz, EPA Region II Risk Assessor Robert Alvey, EPA Region II Hydrogeologist Tom Roche, US ACOE;PM
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The purpose of the site inspections was to assess the protectiveness of the remedy. Both sites were found to be in good condition and,no significant issues were identified. (
Interviews:
Michelle Granger of EPA has discussed the ongoing groundwater remedy with the five year review team, the Montgomery Township Health Officer and the Borough of Rocky Hill Engineer. There were no significant issues ot coricerns raised about the protectiveness of the remedies in place at the sites. After the site inspection, EPA also spoke with representatives of NJDEP regarding the remedies and NJDEP ingicated that they did not have any specific concerns regarding the selected remedies to report at this time ..
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VI. Technical Assessment
. Question A: Is the remedy functioning as intended by the decision document?
Yes, the remedies for the Montgon:tery Township Housing Development and Rocky Hill Municipal Well sites are functioning as -intended by the decision documents.
The sites have been separated into two operable units (OU). OJ]l addressed the provision of an alternate water supply to the residents of the Montgomery Township Housing Development. Once the alt~rnate water supply was completed, no private wells are in use and the ingestion of contaminated grollndwater has been stopped.
OU2 addresses the contaminated groundwater plume. The remedy includes extraction of the contaminated groundwater from the two most contaminated area of the aquifer through pumping,
/ followed by on-site treatment with liquid-phase granular activated carbon (GAC) adsorption. After treatment, the water is discharged to surface water. A groundwater sampling program to monitor the effectiveness of the cleanup has also been implemented. The data trends collected
. from the effluent of the treated groundwater indicate that the remedy is functioning as intended by the decision documents. \ ~
A CEA application will be submitted to NJDEP for State review. Establishment ofa CEA by NJDEP will assure that there is no unaccept~ble future use ofthe contaminated groundwater in
. the vi~inity of the sites. .. I
QuestionB: Are the exposure assumptions, toxicity data, cleanup levels, and remedial response objectives used at the'time ofthe ''remedy selection still valid? .
There have been no physical changes to the sites that would adversely affect the protectiveness . of the remedy. Land lise assumptions, exposure assumptions and pathways, and cleanup levels
considered in the decision documents followed the Risk Assessment Guidance for Superfund
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used by the Agency and remain valid. Although specific parameters ~ay have changed since the time the risk assessment was completed, the process that was used remains valid.
The evaluation of groundwater in this review focused on two primary exposure pathways, direct ingestion (as a potable water source) and the possibility of vapor intrusion into buildings constructed over the plume. The evaluation of the direct contact 'pathway showed that nearby residents are on public water supplies, and since they are not using the contaminated wells for drinking water purposes, there is no current exposure. In addition, the contaminated groundwater is being captured and treated. Therefore, the remedy is protective for the direct 'contact route of exposure. The groundwater remediation response objectives selected in the ROD were the federal and state cleanup standards. The cleanup level of 1 ppb for TCE remains protective.
The exposure assumptions and toxicity values used in t4e original risk assessment remain valid. The cleanup levels have not changed since the time of the decision document and they remain valid. The remedial action objectives identified in the ROD remain valid.
The original risk assessment did not address the potential for vapor intrusion. Based on groundwater concentrations of site-related chemicals that exceeded conservative screening values presented in the draft 2002 guidance, "Evaluating the Vapor intrusion into Indoor Air"(USEPA), a vapor intrusion investigation was initiated.
Three rounds of sub-slab and/or indoor VOC analyses were conducted for the site. Round I, initiated in March of 2006, included samples from several residential homes, two industrial buildings and an adjacent shopping center. Residential samples were collected from six homes located on nearby Robin Drive and Oxford Circle. Sub-slab results for five of the six homes were non detect for TCE and PCE. In the sixth ,home, TCE was not detected; PCE was detected with'in the acceptable risk range at a concentration of 5.48 micrograms per cubic meter (llg/m3) .. Two industrial bl;lildings, one on Route 206 and one on Route 518 were sampled for sub-slab . VOC concentrations. In addition, one sub-slab sample from the shopping center, located ' approximately in the middle, of the property, was analyzed. Results collected from the one
. . 3 . . sample taken in the shopping center, showed elevated levels of PCE, at 177 Ilg/m . The
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shopping. center is comprised of three one story buildings, each of which contains several storefronts. The concentrations at all other 10catioI)s fell into an acceptable risk range as specified in the Vapor Intrusion Guidance.
The collection of Round II soil vapor samples was conducted in June of 2006. The sub-'slab soil gas was sampled at fo~r homes on Merritt Lane. The home where PCE was detected in the subslab during Round I (mentioned above) of vapor samples, was samplyd again during Round II in the indoor air and sub:-slab. In all the above meritioned homes, the detected TCE and PCE concentrations were well within the acceptable risk range. Additionally, the two industrial sites sampled in Round I and three stores located in the shopping center were sampled. The two industrial sample sites id'entified elevated levels of indoor TCE (0.64 to 0.83 Ilg/m3). However, the1sub-slab samples showed concentrations ofTCE which were lower than the i~door values
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indicating a potential indoor source other'than the site-related groundwater contamination. Furthermore, these levels were within the acceptable range. There were seVeral exceedanc.es in the commercial sampling locations within the shopping center. The concentration ofTCE sampled from a vacant store front,formerly call~d WoodStuffwas 4.4 !-tg/m3 and 3.4 !-tg/m3 for sub-slab and indoor samples, respectively. D~e. to the fact that the sub-slab and indoor air . concentratiori are similar and do not follow the typical profile for attenuation (the typical profile allows for an at~enuation of approximately an order of magnitude as vapors migrate from sub- . slab to indoor), the indoor air coric~ntration indicates a possible indoor source ofTCE. Sub-slab' and indoor PCE concentrations of 150 !-tg/m3 and 2.2 !-tg/m3, respectively; were reported. . Although elevated, these concentrations fall into the acceptable cancer risk range. Ewing Sports
_had sub-slab TCE concentrations of9Q !-tg/m3and indoor TCE concentrations of2.2 !-tg/m3. These concentrations are at the upper-bound of the acceptable risk range; further monitoring to ensure protectiveness was determined to be necessary.
Round III sampling locations included four additional commercial stores located in the shopping center. crs Variety sub-slab PCE concentration was measured at 180 !-tg/m3; the indoor sampling however did not detect anylPCE above the detection limit. The corresponding Verizon sub-slab concentrations. fo'r TCE and PCE were 1,300 uglm3 and 1,700 !-tg/m3. Again, the indoor sampling did not detect either TCE or PCE. Lastly, the sub-slab sample collected at the Ya-Yas
. was. in exc~edance of the screening value for PCE at 4,300 !-tg/m3. No indoor sampling was . collected for this, store, because a dry-cleaning facility is located next door. Any indoor PCE concentration may likely be from the operations at the dry cleaners and not the groundwater plume associated with this review. To ensure protectiveness, ongoing sampling and monitoring of both sub-slab and indoor VOCs was determined to be nece!)sary for the commercial stores
. located within the shopping center. . .
Question C: Has any other information come to light that could call into question the protectivene~s ofthe remedy? . ,
,
There is no other information that calls into 'question the protectiveness of the OUI and OU2 remedies. No ecological targets were identified during the baseline risk assessment and none , were Identified during the five-year r:eview, and therefore monitoring of ecological targets is not
. necessary.
Technical Assessment Summary i _
According to the reviewed data, the site inspections, the OUI and OU2 groundwater remedies are functioning as intended by the ~e.cision documents.
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\ VII. Issues, Recommendations and Follow-up Actions
Issue Recommendations & Follow-up Actions
Party Responsible
Oversight Agency
Milestone Date , .
Affects Protectiveness?
(YIN) Current I Future
CEA To be established NJ,DEP NJDEP ongoing N I Y
VIII. Protectiveness Statement
The remedies at the MTHD and RHMW S~perfundsites are protective of human health and the environment. Implementation of the QUI and QU2 remedies has provided for the prqtection of public health and the environment by connecting affected residents to the public water supply, sealing of private water supply and monitoring wells within the contaminant plume, and pumping and treating of contaminated groundwater, thereby eliminating the possibility of, exposure to the contaminated groundwater. Groundwater sampling w.ill be continued as part of long-term groundwater monitoring program. The remedies are protective in the short-term. In order for the remedies to be protective in theIOng-terin, the action identified in Section VII needs to be taken to ensure protectiveness.' '-
IX. Next Review
The next Five-Year Review for the Montgomery Housing Township Development and Rocky Hill Municipal Well Sites should be completed before April 2015. "
/I~ t"l.-D/O
Date Emergency and Remedial Response Division
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ATTACHMENT A ~ LIST.OF ACRONYMS
ACO ARARs CEA CERCLA EPA ESD GWTF GWQS MeL MNA
, MSL NJDEP NPL OU PCOR ppb ppm PQL PRP RA RAWP RD RVFS, ROD RPM ugil Ilg/m~ VOCs
Administrative Consent Order Applicable or Relevant apd Appropriate Requirements Classification Exemption Area' Comprehensive Environmental Response, Compensation, and Liability Act Environmental Protection Agency Explanation of Significant Differences Groundwater Treatment Facility Groundwater Quality Standard Maximum Contaminant Level Monitored Natural Attenuation Mean Sea Level --,.I
New Jersey Department of Environmental Protection National Priorities List Operable Unit Preliminary Close-Out Report Parts Per Billion Parts Per Million Practical Quantitation Level Potentially Responsible Party Remedial Action Remedial Action Work Plan Remedial Design Remedial Investigation/Feasibility Study Record of Decision Remedial Project Manager Micrograms Per Liter Micrograms Per Cubic Meter Volatile Organic ·Compounds
ATTACHMENT,B - LIST OF DOCUMENTS REVIEWED
Record of Decision for OUl, -dated September 29, '1987 Record of Decision for OU2, dated June 30,1988 . RHMW and MTHD Remedial Design, Groundwater Treatment Systems Report, May 2003 Preliminary Clos~out Report, August 2005 Explanation of SignificantDifferences, August 2005 . RHMW and MTHD Final Remedial Action Report, September 2005
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Groundwater Data Summary forRHMW/MTHD Superfund Sites LTRA, October 2004 - June 2007 Groundwater Data for RHMW/MTHD Superfund Sites LTRA, September i007 , . Groundwater Data for RHMW/MTHD S'uperfundSites LTRA, December 2007 Ground\\::ater Data for RHMW IMTHD' Superfund Sites LTRA, March 2008 Groundwater Data for RHMW/MTHD Superfund Sites LTRA, June 2008
. Groundwater Data for RHMW/MTHD Superfund. Sites LTRA, September 2008 Groundwater Data for RHMW/MTHD Superfund Sites LTRA, December 2008 Groundwater Data for RHMW/MTHD Superfund Sites LTRA, March 2009 Groundwater Data for RHMW/MTHD Superfund Sites LTRA, June ~009 Groundwater Data for RHMW/MTHD Superfund Sites L TRA, September 2009
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ATT ACHMENT C - GROUNDWATER CONTAMINANT TRENDS
TCE - Maximum Concentrations Detected I
PCE - Maximum Concentrations Detected
(
are parts per billion (ppb). peE Perchloroethylene
TOWNSHIP
x:
t
l.nc ........... f'U.III[ ........... AllI~1U'IIaDf1S1IC~ftIILINn'BIJI ~ AIDISl UXD ICD..,.,. IIQC:OjCOf'l'llAlXIN ~ n. ~nDIl AT ... WWr.'IIOL M COt1lUI.....,.", M~~ COlT........... 1ID .... .,tM~I'tOITI.
I. nc: ~~ PMWh'. oIIIIlttCMi4, DMDIP,.... M ......... mt(UIDII'...n:. [XD:D!I..ap OI~ lUll ..~ {UO "I/LJ" ~AlbI: ...' .. "D.lVA1'DL
:a. SIl "''lUll ...., 'KI'aIWMC ~tDII ~ n IDInDIDn' ~. N"III.1_mtDL
D'P. ENVhlvNMI:N f . .I,.L--c:.r.-I ........ D~ (DOl) 81M - 111'1'8
u ......·_-,,_cor._
FJGURE-1 SHEET I or 1
