SAMPLING AND ANALYSIS PLANREMEDIAL INVESTIGATION/FEASIBILITY STUDY

WESTINGHQUSE PLANT SITECUMBERLAND TOWNSHIP

ADAMS COUNTY. PENNSYLVANIA

PROJECT No. 87-375SEPTEMBER 8, 1989

PAUL C. Rizzo ASSOCIATES, INC.300 OXFORD DRIVE

MONROEVILLE, PENNSYLVANIA 15116PHONE: (412) 856-9700TELEFAX: (412) 856-9749

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TABLE OF CONTENTS

PAGE

1.0 INTRODUCTION 1

2.0 PROJECT BACKGROUND AND PHASE I RESULTS 4

2.1 PROJECT BACKGROUND 42.2 RI/FS OBJECTIVES 52.3 SUMMARY OP PHASE I 72.4 ASSESSMENT OF PHASE I FINDINGS 11

3.0 DATA GAPS 14

4.0 PHASE II SAMPLING AND ANALYSIS ACTIVITIES 17

4.1 INSTALLATION OF ADDITIONAL MONITORING WELLS 174.2 SAMPLING AND ANALYSIS OF MONITORING WELLS 184.3* PHASE II TEST BORING PROGRAM 194.4 ADDITIONAL SURFACE WATER SAMPLING 194.5 SURVEY OF OTHER POTENTIAL SOURCES 204.6 DATA QUALITY OBJECTIVES FOR PHASE II 21

5.0 TREATABILITY STUDIES 23

6.0 NON-TECHNICAL CONSIDERATIONS RELATED TO PHASE II STUDIES 25

7.0 PROJECT ORGANIZATION FOR PHASE II ACTIVITIES 26

8.0 SCHEDULE 27

9.0 SUMMARY 28

REFERENCES

TABLES

FIGURES

APPENDIX A: SELECTED REFERENCES

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I , SAMPLING AND ANALYSIS PLANREMEDIAL INVESTIGATION/FEASIBILITY STUDY

HESTINGHOUSE PLANT SITECUMBERLAND TOWNSHIP

ADAMS COUNTY, PENNSYLVANIA

1.0 INTRODUCTION

A Work. Plan for a Remedial Investigation/Feasibility Study (RI/FS) forthe Westinghouse Plant Site was prepared by Paul C. Rizzo Associates,Inc. (Rizzo Associates) on behalf of the Westinghouse ElectricCorporation (Westinghouse) in accordance with the consent order betweenWestinghouse and the U.S. Environmental Protection Agency, Region III(USEPA) dated March 10, 1987 (USEPA Docket No. III-87-4-DC). The WorkPlan has been prepared in accordance with the RI/FS guidelines presentedin the National Contingency Plan published in the Federal Register

. (November. 20, 1985) and Section 1.2.1 of the Superfund Amendments and^— • Reauthorization Act (SARA). The Work Plan was submitted to the USEPA on

February 11, 1988. The Work Plan was conditionally approved by theUSEPA in September 1988 and unconditionally approved on or aboutDecember 1, 1988.

As described in the Work Plan, the RI portion of the project waspresented as a two-phased study. Phase I has been completed and isdocumented in a Phase I Report issued in June 1989 (Rizzo Associates,1989a). As the scope of the second phase (Phase II) is contingent uponresults of the first phase (Phase I), the RI/FS process provides forphased submittals to effectively utilize the phased approach. ThisSampling and Analysis plan is part of that process. In addition, arevised Work Plan (Rizzo Associates, 1989b) has been prepared. ThisSampling and Analysis Plan should be reviewed as an extension of theWork Plan and the comprehensive Phase I Report.

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The emphasis in Phase I, as part of the RI/FS scoping process, was todetermine compounds of interest at the site and to assess the physical v—characteristics of the site such as geology and hydrogeology. The firstphase included such tasks as fracture-trace analysis; drilling andlogging of borings; installation of monitoring wells; ground water,soil, surface water, and sediment sampling and analysis; a plant pipingsurvey; physical and chemical site characterization; a preliminaryevaluation of contaminant fate and transport; and identification ofadditional data needs. Based on the results of the Phase Iinvestigation, additional site work will be conducted in Phase II toassess the extent of contamination and to obtain additional datanecessary for the proper evaluation of remedial alternatives andperformance of an endangerment assessment.

The purpose of this submittal is to document the performance of Phase IIand to indicate how the results of Phase II will be incorporated intothe overall RI/FS process. Subsequent sections of this Sampling andAnalysis Plan (SAP) are: j

• Section 2.0: Project Background and Phase IResults

• Section 3.0: Data Gaps

• Section 4.0: Phase II Sampling and AnalysisActivities

• Section 5.0: Treatability Studies

• Section 6*0: Non-Technical ConsiderationsRelated to Phase II

• Section 7.0: Project Organization for Phase IIActivities

• Section 3.0: Schedule

• Section 9.0: Summary

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In preparing this Sampling and Analysis Plan, provisions of the WorkPlan and the Phase I Report have not been repeated; this SAP should bereviewed as an extension of those documents and not as a self-standingdocument. In addition, technical procedures described in the QualityAssurance Project Plan (Rizzo Associates, 1988c) and in the SiteOperations Plan (Rizzo Associates, 1988b) are not modified by thisdocument except where specifically noted otherwise. In particular,procedures that have been used and adopted for Phase I sampling andanalysis will be utilized in Phase II except where noted otherwise.

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2.0 PROJECT BACKGROUND AND PHASE I RESULTS

2.1 PROJECT BACKGROUNDThe Westinghouse Plant Site has an area of approximately 90 acres and islocated along the west side of Biglerville Road (Route 34),approximately 1.5 miles north of downtown Gettysburg in CumberlandTownship, Adams County, Pennsylvania. The site location map is providedas Figure 2-1 of the Work Plan. The vicinity is semirural withresidential development, light industry, and some farmlands. The sitecoordinates are latitude 39°, 51 minutes, 3 seconds; and longitude 77°,14 minutes, 21 seconds.

There are two intermittent unnamed streams which drain the site. Onestream is located north and the other east of the plant facility. Thesestreams flow into another unnamed stream which in turn flows to a localwater course known as Rock Creek. The locations of these streams, theplant facility, Rock Creek, and other general physical features are ishown on Figure 2-2 of the Work Plan (Rizzo Associates, 1939b).

The plant was constructed in 1963 for elevator component manufacturingoperations. The manufacturing processes consist of several steps whichare described in the Phase I Report (Rizzo Associates, 1989a). Chemicalfeed materials utilized in plant operations include solvents, paints,cutting and lubricating oils, and insulation board. Trichloroethene(TCE) was the primary solvent used at the plant until about 1975 when1,1,1-Trichloroethane (TCA) was substituted for TCE. Waste materialsincluding spent solvents are drummed and stored on-site before beinghauled off-site for disposal. A flow chart summarizing plant operationsis included on Figure 2-6 of the Work Plan (Rizzo Associates, 1989b).

Environmental contamination at the plant site was first suspected in1933 based upon reports from local residents to the PennsylvaniaDepartment of Environmental Resources (PADER). These reports lead tosampling by PADER, Westinghouse, and USEPA Region III. The site /

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l chronology and sampling activities are summarized in Table 2-3 of theWork Plan (Rizzo Associates, 1989b). In June 1984, Westinghousevoluntarily installed and began periodic operation of a groundwaterextraction and treatment system on the property. During normaloperations, water was pumped from a well (designated as PMW-1 in thisreport) at a rate of approximately 17 gallons per minute and treatedusing an air stripping column. The water was then discharged to a plantstorm sewer which in turn discharges to the stream located north of theplant along Boyd School Road. The groundwater extraction and treatmentsystem was installed in June 1984 and operated, except during certainperiods, until August 1987. The system was refurbished and upgraded inlate 1988 and restarted under an order from the Pennsylvania Departmentof Environmental Resources (PADER) in February 1989.

Other remedial activities which Vestinghouse has undertaken at the siteinclude removal and off-site disposal of contaminated soil and theinstallation of an alternate public water supply.

W2.2 RI/FS OBJECTIVESAs documented in the Work Plan, the overall objectives of the RI/FS areas follows:

• Identify potential sources of contamination.Specifically, assessment of source areas whichcould release contaminants to the environment.

• Identify the nature and extent of currentcontamination.

• Assess pathways of migration.

• Assess risk (endangerment assessment).

• Identify remedial alternatives including the no-action alternative given that significantremediation has already occurred.

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• Evaluation of remedial alternatives in terms oftechnical feasibility, estimated costs, andeffectiveness in reducing public health andenvironmental risk.

Phase I was initiated in December 1938 and culminated with the issuanceof the Phase I Report in June 1988. The goals of Phase I, as documentedin the Work Plan, were as follow:

• Characterize bedrock fractures through afracture trace study.

• Characterize the site geology.

• Document site climatic conditions.

• Identify compounds of interest.

• Characterize the site hydrogeology.

• Assess vertical and lateral flow gradients atthe site.

• Identify compounds of interest.

• Study the vertical and lateral extent of soilcontamination.

• Assess whether nearby streams are currentlytransporting contaminants from the site.

t Assess groundwater conditions beneath the site.

• Clarify current and designated uses ofgroundwater and surface water.

These activities, performed as part of the RI/FS scoping process, havebeen completed and documented in the Phase I Report (Rizzo Associates,1989a). The following section summarizes the Phase I studies and thefindings of that investigation.

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i 2.3 SUMMARY OF PHASE I^~^ The scope of Phase I placed emphasis on defining compounds of interest

(COI) and geotechnical, geological, and hydrogeological characteristicsof the plant area. The scope, goals, and objectives were described inthe Phase I RI/FS Work Plan dated February 1988 and approved by theUSEPA and PADER in late 1988. Specifically, this study included afracture trace analysis; drilling and logging of borings; installationof monitoring wells; groundwater, soil, surface water, and sedimentsampling and analysis; a plant piping survey; physical and chemical sitecharacterization; an evaluation of contaminant fate and transport; andidentification of additional data needs.

A total of six new borings were drilled to supplement ten deep boringspreviously drilled by R.E. Wright Associates (Wright) in 1984. Datafrom 43 shallow soil borings drilled in 1968 for a geotechnicalinvestigation and from five shallow borings drilled by Wright in 1984were also used to characterize the subsurface. Monitoring wells were

I 1 installed in five of the six new borings and in nine of the boringsdrilled in 1984.

Data obtained from the subsurface investigation indicate thatgroundwater movement is characterized by fracture flow in the siltstonesand shales of the Gettysburg Formation underlying the site. Recharge ofthe groundwater occurs as precipitation infiltration through the soiloverlying the bedrock. Areas where the soil was removed, such as thenorthwest corner of the plant, are possibly areas of increasedgroundwater recharge. Another area of interest is the location of aformer farm pond near the front entrance to the plant. The burieddepression'associated with this former pond may continue to influencesubsurface flow patterns.

Other potential areas where increased infiltration into bedrock couldoccur are the numerous geotechnical borings drilled during pastinvestigations. Where located, these borings were observed to be open

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holes. The previously existing monitoring wells installed in 1984 werealso open holes until well screens and appropriate seals were installedat specified depths during the Phase I investigation. The well (PMW-1)used to extract groundwater still remains an open borehole and pumpsgroundwater from both the shallow and deep zones.

Once groundwater reaches bedrock, the overall directorial gradient iseastward towards Rock Creek. Monitoring wells screened withinapproximately SO feet of the surface and those screened deeper thanapproximately 120 feet both show gradients towards Rock Creek. Based ondata obtained during the subsurface investigation, it is probable thatthe groundwater from the shallow monitoring wells has a naturalhydraulic connection with the groundwater monitored in the deep wells.These groundwater zones were connected where the 1984 borings remainedopen.

The hydraulic head measured in the shallow monitoring wells is higherthan the head measured in the deep wells. This indicates that there isa downward component to the groundwater flow direction. This downwardgradient is amplified by the current pumping program at PMW-1 ordered byPADER.

One of the observations made during pumping is that drawdown iselongated in the direction of geologic strike. In the area of theWestinghouse Plant Site the beds strike approximately N23°E and dip 23°to the northwest. As stated previously, the overall direction ofgroundwater flow is towards Rock Creek. Based upon findings of Phase I,groundwater flows across the bedding planes and is subsequentlyinfluenced by nearby vertical tectonic joints which offer flow paths toRock Creek.

A fracture trace analysis was conducted to assess whether linearfeatures observed on aerial photographs could aid in the identificationof major fractures which in turn could influence specific paths of

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i , groundwater flow. Host fracture traces were found to correspond tobedding plane alignments and none were observed to correspond toprincipal joint directions observed in the immediate vicinity of theplant.

Generally speaking, under natural flow conditions, groundwater beneaththe Westinghouse Plant Site tends to move laterally through joints inthe direction of Rock Creek and also downward where joints and/orborings facilitate this movement. The presence of relatively permeablebedding planes allows for localized flow and dispersion along the N23°Etrend (i.e., geologic strike).

Samples of soils, surface water, sediments, and groundwater have beenanalyzed for the substances which comprise the Target Compound List(TCL). Based on these analyses, compounds of interest for theWestinghouse Plant RI/FS have been defined and include three volatileorganic compounds (VOCs): trichloroethene (TCE), 1,1-dichloroethene

V^J (1,1-DCE), and 1,1,1-trichloroethane (TCA). Soil samples were collectedfrom five potential source areas. Analytical results indicate that thefive potential source areas sampled are not significant contributors tothe groundwater conditions observed. The surface water and sedimentdata, including storm drain and roof water samples, indicate that thenearby streams, with one possible exception, currently do not receivenor act as migration pathways for compounds of interest. Thedistribution of VOCs in groundwater suggest that the former pondlocation beneath the plant and grounds is potentially a source area.The extent of VOC distribution in the shallow wells appears to bedefined in the east and west directions, but not in the north and southdirections and the extent of VOCs in the deep wells has not beencompletely defined. However, the concentrations of VOCs in both theshallow and deep wells decrease rapidly within the limits of theWestinghouse Plant Site property and with increasing distance from theformer pond location.

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Based on analytical results of groundwater samples collected from thesite monitoring wells, the distribution of VOCs indicates that the x—shighest concentrations were found in the vicinity of the former pond.VOC concentrations decrease rapidly in both the shallow and deep wellswith increasing distance from the former pond location. The dataindicate dispersion of VOCs parallel to geologic strike with limitedmigration in the downgradient direction. An occurrence of VOCs wasdetected in an upgradient deep monitoring well which was screened acrossthe same bedding plane that intersects a .shallow monitoring well in thevicinity of the former pond. This implies that VOCs are eitherdispersing along permeable bedding planes contrary to the overalldirection of groundwater flow or that a source exists upgradient of theplant. Upgradient dispersion would likely be bounded by a verticaligneous dike located west of the site.

Based only on the the data obtained during the Phase I study, assessmentof the results would indicate that elevated VOC concentrations ingroundwater appear to occur primarily within site boundaries. Previous ,investigations conducted by PADER have detected VOCs in residentialwells, which suggests substantial off-site occurrences of VOCs. Theusefulness of this residential well data, however, is somewhatrestricted by the limited information on well construction, the practiceof sampling different wells during each event from 1983 through 1986,and the absence of quality control and data validation informationassociated with the PADER sampling program. The residential well dataindicates that VOCs have been detected downgradient of the plant withapparent lateral dispersion. However, because of the limited wellconstruction data and random sampling procedures, the data cannot beused to quantitatively define a plume or evaluate whether preferredfracture pathways are present. Thus, the pattern of results indicatesthe possibility that multiple off-site sources may be responsible forthe occurrence of VOCs in residential wells.

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In addition, the limited well construction data available for theresidential wells indicate that the 'majority of these wells areshallow. Phase I results of the site monitoring wells indicated thatdowngradient concentrations of VOCs in the shallow wells decreaserapidly within the site property. These data also suggest that multipleoff-site sources may be responsible for the occurrence of VOCs inresidential wells.

In summary, VOCs have been detected in the groundwater beneath the site;overall groundwater flow is eastward toward Rock Creek with a flowcomponent along the relatively permeable bedding planes (N23°E);previous residential well sampling and analyses performed by PADERdetected VOCs in the groundwater downgradient of the site; and thesource(s) and distribution of VOCs in the groundwater has not been fullydefined. It should be noted that certain removal and remedialactivities have been completed and that an permanent alternate watersource has been supplied to residents immediately downgradient of thesite.

2.4 ASSESSMENT OF PHASE I FINDINGSA major finding of the Phase I study is the presence of compounds ofinterest (COI) in the groundwater. The COI identified for theWestinghouse Plant Site are TCE, 1,1-DCE, and TCA which can beclassified as dense nonaqueous phase liquids (DNAPLS). The presence ofelevated concentrations of COI in groundwater samples obtained from theformer pond location indicates a potential for the presence of DNAPLS inthe subsurface regime at this location. The mechanisms by which theseDNAPLS entered the hydrogeologic regime is currently not apparent. Themechanisms could be related to historic plant operations or to disposalactivities which took place at the former pond location prior to plantconstruction. Regardless of the nature of occurrence, the presence ofDNAPLS in the hydrogeologic regime indicates an extremely complexremedial situation. Although the COI are considered soluble and mobilein groundwater, the geochemical mechanisms by which concentrated phases

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of these compounds affix themselves to soil and rock are such that thedissolution of these compounds from the soil and rock is onlyaccomplished after an extended period of exposure to groundwater.

The remediation of groundwater contamination problems due to thepresence of DNAPLS in the subsurface regime is the recent subject ofmuch dialog within the hydrogeologic community (Freeze and Cherry, 1989;Hall, 1989; USEPA, 1939). Simply stated, improving groundwater qualityimmediately beneath the Westinghouse Plant Site to drinking waterquality within the next few years is not an achievable goal with currenttechnology at any cost. However, to monitor and control the impacts, toreduce the potential for future contamination, and to contain impactswithin the site property are reasonable and probably achievable remedialgoals* As indicated in Freeze and Cherry (1939), it is likely that therealistic and achievable remedial measures to be assessed for theWestinghouse Plant Site will include ongoing monitoring and continuedcontrol.

Appropriate remedial measures for assessment will likely include the"no-action" alternative (given the previous remediation programs thathave been completed); some combination of source removal or sourcecontrol to the degree practicable; alteration of migration potentialthrough hydrodynamic control associated with pumping and treatment ofthe groundwater removed from pumping (i.e., plume control);institutional control for the use of groundwater; and monitoring todocument that the fundamental assumptions upon which remedial measuresare based are realized during the remedial process.

Based on recent presentations by research personnel of the USEPA'sRobert S. Kerr Environmental Laboratory (Hall, 1939 and USEPA, 1989) andrecent publications (Freeze and Cherry, 1989) associated with the topicof groundwater remediation at sites characterized by DNAPLS, long-terminstitutional controls for the use of groundwater within the siteproperty will be appropriate and necessary for the foreseeable future.

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Because of the probable need for long-term institutional controls,future discussions should be held with local governmental agencies andwater authorities including the Gettysburg Water Authority as regardscurrent operations and future plans for the distribution and developmentof local water supplies.

Three recently-published papers upon which the discussions of thissection have been based are included as Appendix A.

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3.0 DATA GAPS ,

Based on the data obtained during the Phase I study, the need foradditional data to fully evaluate the risk and appropriate remedialresponses for the site was assessed. Review of the Phase I dataindicates that potential source areas have been characterized. Thesurface water and sediment data, including storm drain and roof watersamples indicate that the nearby streams, with one possible exception,currently do not receive compounds of interest attributed to thefacility, nor do the streams act as significant migration pathways. Thedistribution of VOCs in the groundwater suggests that the former pondlocation is a potential source area of VOCs in the groundwater at theplant area. The extent of VOC distribution in the shallow wells appearsto be defined in the east (downgradient) and west directions, but not inthe north and south directions and the extent of VOCs in the deep wellshas not been defined. However, VOC concentrations in both the shallowand deep wells decrease rapidly within the Westinghouse Plant Site v Jproperty and with increasing distance from the former pond location.

In order to assess the Phase I data and the need for additional data, apreliminary determination of Operable Units associated with theremediation of this site and preliminary remedial objectives have beenmade. Based on the findings of the Phase I studies, the followingOperable Units must be considered:

t A plume of groundwater contamination (OperableUnit 1); and

• Probable subsurface source area (Operable Unit2) of contamination in the former pond locationwhich serves as an apparent source of thegroundwater contamination plume.

It must be noted, based only on the data obtained during the Phase Istudy, that the groundwater contaminant plume, i.e., Operable Unit 1

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does not appear to exist beyond the limits of the site property. Basedon the preceding information, preliminary remedial objectives associatedwith each Operable Unit are as follows:

• Operable Unit 1 - Groundwater Contamination Plume- Containment of the groundwater contaminationplume such that further impacts beyond thelimits of the site are mitigated.

- Establishment of institutional controls withinthe site property for areas in whichapplicable or relevant and appropriaterequirements (ARARs) cannot realistically beobtained.

• Operable Unit 2 - Former Pond Location- Characterization of the potential source areaand its relationship to Operable Unit 1.

- Prevention of future off-site impacts due tothis potential source area*

It is important to note that the remedial goals for both Operable Unitsmay in fact be shown by the RI/FS process to be obtainable through theremedial actions that have already been completed at the site. Remedialactions completed at the Westinghouse Plant Site include installation ofa permanent alternate water supply; the plugging of floor drains withinthe facility; the removal of certain areas of contaminated soil at thefacility; the discontinuance of the use of TCE at the facility; theproper sealing of open boreholes at the site; and the ongoing operationof the groundwater pump and treat program currently ordered by thePADER. Given that these actions have either been completed or arecurrently underway, it is quite possible that no additional remedialmeasures are necessary in order for this site to achieve compliance withapplicable goals under CERCLA. In order that this determination and theproper assessment of additional remedial measures can be completed inaccordance with the provisions of the law, the Consent Decree, and thecurrent guidance documents, certain additional data must be acquired.

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Data gaps which must be filled in order to properly complete the RI/FSprocess for both Operable Units at this site were described in the PhaseI Report (Rizzo Associates, 1939a) and are repeated below.

Based on the preceding information, additional data for evaluation ofrisk and remedial alternatives include:

• Sampling and analysis of existing monitoringwells located west of the plant.

• Drilling and installation of shallow and deepmonitoring wells north, south, and east of theplant.

• Installation of a properly sealed, cased, deep-screened monitoring well at PMW-1 and drillingand installation of a properly sealed, cased,shallow-screened monitoring well nearby.

• Groundwater sampling and analysis of the Phase Iand proposed Phase II monitoring wells.

• Implementation of controlled, short-durationpumping tests in the shallow and correspondingdeep well at the the PMW-1 location withtreatment of the water from both wells providedby the existing air stripping tower.

• Subsurface soil sampling and analysis in thevicinity of the former pond location.

• Surface water sampling and analysis of thetributary east of the plant.

• A survey of other potential sources within theplant vicinity.

Successful completion of the activities described above will facilitateevaluation of risk and remedial alternatives. Based on the assessmentof the data acquired, the recommendation of immediately implementing aplume contaminant remedial measure for Operable Unit 1 as a CERCLAInterim Measure may be-made at the conclusion of the Phase II studies.The feasibility study would then focus on Operable Unit 2 while measuresare implemented to mitigate near-term off-site impacts (if any).

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4.0 PHASE II SAMPLING AND ANALYSIS ACTIVITIES

Phase II sampling and analysis activities will be undertaken in order toprovide information and response to data gaps identified in the previoussection. Specific activities to be performed are described in thefollowing subsections. The procedures for these activities, exceptwhere noted otherwise, will be consistent with those utilized for thePhase I investigation and documented in the QAPP (Rizzo Associates,1988c) and the Site Operations Plan (Rizzo Associates, 1988b) which havepreviously been submitted and approved by the agencies.

4.1 INSTALLATION OF ADDITIONAL MONITORING WELLS

— As described in Section 2.3 and 3.0 of this SAP, the following findingswere disclosed by the Phase I study. Groundwater flow, and subsequentlymigration of compounds of interest, is highly influenced by localgeologic structure. The nature and extent of groundwater contamination

V j appears to be related to a subsurface feature in the vicinity of a pondwhich had previously existed on the property. The extent of apparentgroundwater contamination appears to be limited to the confines of thesite property. However, the extent of groundwater contamination has notbeen fully defined by the Phase I study. Therefore, for purposes ofobtaining data for determining the extent of contamination at the site,for assessing remedial alternatives related to plume containment, andfor performing an endangerment assessment, additional monitoring wellsare proposed. This is of particular interest since the Phase Iinvestigation indicated that contamination is largely limited to thesite property. However, earlier investigations performed by PADER asdescribed both in the Work Plan and the Phase I Report indicatedrelatively wide-spread off-site occurrence of volatile organic compoundsin the groundwater.

IFigure SAP-1 indicates the occurrence of total- VOC concentrations in theshallow bedrock wells as measured during the Phase I study. Based on

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the information presented on that figure, three additional shallowmonitoring wells are proposed. Additional wells proposed in this Phase ^-^II investigation to monitor the shallow hydrogeologic regime are denotedas PMW-11A, PMW-12A, and PMW-13A. These wells are intended to provideadditional data on the extent of contamination in the shallowgroundwater regime.

Figure SAP-2 indicates the distribution of total VOC concentrationsobserved in the deep wells during the Phase I studies. Based on thisdistribution, additional data are recommended for purposes of assessingthe extent of contamination in the deeper groundwater regime. Based onthe information graphically depicted on Figure SAP-2, four additionalmonitoring wells are proposed to monitor the deep hydrogeologic zone.These wells are denoted as Wells PMW-11B, PMW-12B, PMW-13B, andPMW-14. These wells are intended to provide additional data on theextent of contamination in the deeper groundwater regime.

In addition to the seven proposed monitoring wells, it is recommended ;that existing Well PMW-1 be properly sealed, cased, and screened tomonitor the deeper hydrogeologic regime and that a shallow monitoringwell be installed nearby. These wells are denoted PMW-1A and PMW-1B andare intended to provide additional data on the extent of contaminationin the vicinity of the former pond location. In addition, controlled,short-duration pumping tests in both PMW-1A and PMW-1B are proposed toobtain additional data on aquifer characteristics and to evaluate theeffectiveness of a groundwater pump and treat program.

The proposed locations for the wells mentioned above are depicted onFigure SAP-3. A tabular description of the proposed new wellinstallations is provided on Table SAP-1.

4.2 SAMPLING AND ANALYSIS OF MONITORING WELLSBoth the wells installed during Phase I and the nine new wells proposedfor installation during Phase II of the investigation will be sampled

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and analyzed for the compounds of interest identified for thisproject. The analytical procedures which will be utilized will be thosefor volatile organic compounds as indicated in the QAPP. In addition,water levels will be recorded as described in the QAPP.

4.3 PHASE II TEST BORING PROGRAMThe Phase I study indicated the likelihood of a potential source ofgroundwater contamination in the vicinity of a former pond located nearthe front of the existing plant building. This location is in thevicinity of PMW-9A, PMW-9B, and PMW-1 (Figure SAP-1). In order toobtain additional information on this area for purposes of assessingremedial options related to source removal, source treatment, and sourcecontrol, five shallow test borings are proposed. The locations of theseborings are depicted on Figure SAP-3. These borings will be drilleduntil the bedrock surface is encountered. The borings will becontinuously sampled using an SPT sampler under the procedures describedfor soil drilling in the QAPP (Rizzo Associates, 1988c). The soilsamples will be screened using an organic vapor analyzer for totalheadspace readings. The soil sample obtained from each of these boringhaving the highest headspace reading will be analyzed for volatileorganic compounds on the Target Compound List using the proceduresdescribed in the QAPP. In addition, the deepest soil sample obtained ateach boring will also be analyzed for the same compounds using the sameprocedures. The purpose for installing these boring is to obtainadditional information on the soil stratigraphy and soil conditions inwhat is currently believed to be a potential contaminant source area andto obtain data on the nature and extent of contamination within thesource area. These borings are designated PTB-3, PTB-4, PTB-5, PTB-6,and PTB-7.

4.4 ADDITIONAL SURFACE WATER SAMPLINGThe Phase I investigation indicated that with the possible exception ofseepage from the former pond location into the eastern tributaryupstream of the SW-1 sampling location (Figure 2-2 of the Phase I

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Report), that the streams in the vicinity of the Westinghouae Plant Siteare not serving as pathways of migration for the compounds ofinterest. One of the compounds of interest was detected at trace levelsat the SW-1 location, therefore in order to assess the significance ofthis finding and to further assess the possible significance of thesurface water drainage system as a migration pathway, additional surfacewater sampling is proposed. It is proposed that an additional sample betaken at the SW-1 location and at a downstream location denoted as SW-4(Figure SAP-3). The purpose for sampling at the SW-1 location is toobtain additional data on the presence of volatile organic compounds insurface water at this location. The purpose for obtaining a surfacewater sample at the SW-4 location is to assess the presence of volatileorganic compounds and in particularly the compounds of interest at theintersection of the eastern tributary and the unnamed tributary whichleads to Rock Creek.

The procedures for obtaining surface water samples in Phase II will beconsistent with those described in the QAPP with the additional > Jprovision that the samples will be collected when there is sufficientstream flow to obtain a representative sample. The timing for theacquisition of the samples from these locations will be subject toconditions encountered as regard to adequacy of stream flow forrepresentative sampling.

4.5 SURVEY OF OTHER POTENTIAL SOURCESBased upon the results of the Phase I study, there is a discrepancy withthe apparent distribution of VOCs as disclosed by the Phase I study andthe apparent distribution of VOCs as disclosed by previous sampling ofresidential wells by the PADCR. In order to attempt to reconcile thisdiscrepancy, a survey will be conducted for potential sources, otherthan the Westinghouse Plant Site, responsible for the possible presenceof volatile organic compounds in the hydrogeologic regime. Thesepotential sources include septic tanks which possibly had utilized

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chlorinated solvents as degreasers and cleaning agents, and otherpossible users of volatile organic compounds of a commercial naturePossible effects of other source areas identified will be assessed.

The rationale for this survey is to confirm the appropriateness of asource control measure related to possible sources on the site propertyas regards to mitigating the occurrence of volatile organic compounds inthe hydrogeologic regime.

4.6 DATA QUALITY OBJECTIVES FOR PHASE IIBased on the review of existing data (Section 2.0), the RI/FS objectivesestablished for the site, the preliminary scoping of remedialalternatives, and evaluation of potential ARARs, it is possible toestablish data requirements to complete the RI/FS process. In thissection Data Quality Objectives (DQOs), for the Phase II investigationare identified. DQOs are qualitative and quantitative goals, in termsof precision, accuracy, representativeness, comparability, andcompleteness (PARCC) which are specified for each data set. The PARCCgoals for Phase II remain the same as described in the QAPP (RizzoAssociates, 1988c). DQOs are based on the concept that different data-uses require data of different quality. Data quality is the degree ofuncertainty acceptable for the decisions or conclusions which arederived from interpretation of the data. The decisions or conclusionsderived from the data or data-uses can include site contaminantcharacterization in support of the Endangerment Assessment and remedialalternative evaluation and selection decisions.

DQOs for the Phase II investigation for the Westinghouse Plant Site werebased on the following:

• Comparison of detection limits for availableanalytical methods to applicable or relevant andappropriate requirements (ARARs), risk basedcriteria, and data needs for risk assessment orengineering purposes.

AR30I538

22

Selection of analytical methods that allowquantification of the analytes at levelssufficiently below the ARARs to minimize thenumber of critical data points.

Evaluation of the maximum allowable variabilityin the data based on the ARARs comparison.

Development of site-specific acceptablevariability based on the intended data use andmethod-specific precision and accuracyinformation.

Table SAP-2 presents a summary of the proposed sampling and analysisprogram with DQOs for the Westinghouse Plant Site.

A-R30I-53?'

23

5.0 TREATABILITY STUDIES

Monitoring Well PMW-1 was not modified during the performance of thePhase I investigation. As described in the Phase I Report, thismonitoring well is an open hole which extends uncased through bedrock toa depth of 200 feet below the ground surface and approximately 180 feetbelow the top of bedrock. This well is currently pumped in response toa PADER order for the operation of a groundwater extraction andtreatment system at the site. As described in detail in the Phase IReport, pumping of this well amplifies the downward gradient found toexist at the site under natural (non-pumping) conditions. Thisamplified downward gradient tends to increase the vertical migrationpotential of the VOCs disclosed in the Phase I study. In order to fullyassess the appropriateness of a groundwater pump and treatment programas a remedial alternative it is proposed that a treatability study beconducted as part of the Phase II studies. This study will consist of:

• Shutdown of the current pumping operation andproper removal of the submersible pump andcontrols.

• After full recovery, based on monitoring ofwater levels, geophysical logging of Well PMW-1.

• Pressure testing of zones within this monitoringwell.

• Design and modification of a deep-screened wellwhich will consist of the upper portion of thewell being cased off and the lower portion ofthe well being screened. Well installationprocedures would be similar to those utilizedduring the Phase I study for the modification ofthe other open hole wells at the site.

• Installation of a shallow monitoring wellnearby. Well installation procedures would besimilar to those utilized during the Phase Istudy.

AR30I5UO

24

Discrete sampling of these wells aftermodification and purging.

Performance of short-duration aquiferperformance test in both the shallow and deepwells. Groundwater pumped during the tests willbe treated using the current on-site airstripping treatment system. Pumping rates wouldbe established using step-drawdown tests.

Data obtained from the aquifer performance tests will be evaluated inorder to assess the overall appropriateness of a long-term groundwaterpump and treat alternative for the site.

HR30I5M:

25

6.0 NON-TECHNICAL CONSIDERATIONS RELATED TO PHASE II STUDIES

Several of the proposed well locations for Phase II are outside theWestinghouse Plant Site limits. The expediency with which the projectcan be completed will be partially dependent upon the expediency withwhich access agreements to those well locations may be obtained. It ispossible that relocation of some proposed well locations may be requiredbecause of access problems. Proposed well locations have been basedprimarily on technical considerations and have not been influenced bypossible ease or difficulty with respect to property access.

v

In addition, the proposed well modification for PMW-1 and the aquifer— performance testing proposed at that well location will require

modification of or relief from the current PADER order. If Westinghouseis unable to obtain relief from this order, the treatability studycomponent of Phase II will not be able to be completed. Possible delays

V i associated with these two events and other yet unseen events will bereported in the appropriate monthly progress reports as necessary and/orappropriate.

flR30!5i»2

26

7.0 PROJECT ORGANIZATION FOR PHASE II ACTIVITIES

The project organization for Phase II activities will be, from anorganizational standpoint, identical to the project organizationutilized for Phase I activities* Principal participants are as follows:

• Overall responsibility for the RI/FS process -Westinghouse Electric Corporation.

• Technical coordinator for performance of theRI/FS and principal science and engineeringconsultant - Paul C. Rizzo Associates.

• Drilling and well installation services -Eichelberger, Inc., and Pennsylvania Drilling.

• Laboratory Analysis - Lancaster Laboratories.

Individual personnel assignments for the Phase II sampling and analysisactivities are identical to those described in the approved SiteOperations Plan (Rizzo Associates, 1988b), except that Mr. P.F. O'Uarahas replaced Dr. J.T. Onstott as the Rizzo Associates Project Manager.

AR30l5ii3:

27

8.0 SCHEDULE

The initial schedule for the RI/FS was included as Figure 5-1 of theWork Plan (Rizzo Associates, 1988a). Based upon the scope of Phase II,the schedule has been revised. The revised schedule (Figure SAP-4)provides for the submittal of the draft RI Report, covering both Phase Iand Phase II and the draft Endangerment Assessment Report seven monthsfrom the authorization to proceed with Phase II. The schedule alsoprovides for submittal of the draft Feasibility Study Report withinthree months of receiving USEPA approval of the final RI andEndangerment Assessment Reports.

We believe the revised schedule is realistic given the scope of Phase IIand the required scope of the Endangerment Assessment and FeasibilityStudy. The current schedule, assuming very prompt USEPA review andturnaround of submittals, is for the preparation and submittal of the

I j draft Feasibility Study Report within 11.5 months after receipt ofapproval from the agencies to initiate Phase II. The schedule is alsocontingent upon obtaining prompt modifications to the PADER order tooperate the pump and treat system at the site and obtaining access tooff-site sampling locations.

Please note that at the conclusion of Phase II and the EndangermentAssessment, it may be possible to immediately proceed with a CERCLAinterim measure for Operable Unit 1 (the groundwater).

M18Q154*

ARSOIStti*

28

9.0 SUMMARY

A Sampling and Analysis Plan has been prepared for the WestinghousePlant Site, Cumberland Township, Adams County, Pennsylvania. This Planoutlines the framework for the performance of the Phase IIinvestigation. The schedule provided includes requirements forsubmittal of the draft Feasibility Study Report within 11.5 months ofUSEPA approval for initiation of Phase II. Implementation of an interimmeasure may be possible for Operable Unit 1 prior to initiating thefeasibility study.

We believe this SAP is responsive to the provisions of the Work Plan forthis project and the consent agreement under which the project is beingperformed. It should be noted that certain key considerations relatedto the schedule are beyond the control of Westinghouse. These aspectsare:

• Obtaining access to off-site locations forperformance of sampling, analysis, and drillingactivities.

• Obtaining modification of the PAOER order topump and treat groundwater at the site.

• The review and approval time required by USEPAfor draft submittals in this schedule. Theseinclude the review and approval time associatedwith the Phase I Report, this Sampling andAnalysis Plan, the final RI and EndangermentReports, and the Feasibility Study Report.

Westinghouse and the members of its project team are committed toexpeditious performance of a high quality RI/FS consistent with therequirements and agreements under which this project is being performed.

29

REFERENCES

Freeze, R. A. and J. A. Cherry, 1989, "What Has Gone Wrong," GroundWater, July - August 1989, Vol. 27, No. 4, pgs. A58-464.

Hall, C. W., 1989, "Practical Limits to Pump and Treat Technology forAquifer Remediation," Robert S. Kerr Environmental Research Laboratory,Ada, Oklahoma.

Rizzo Associates, 1988a, "Work Plan, Remedial Investigation/FeasibilityStudy, Westinghouse Plant Site, Adams County, Pennsylvania,"February 11, 1988, Paul C. Rizzo Associates, Pittsburgh, Pennsylvania.

Rizzo Associates, 1988b, "Site Operations Plan, RemedialInvestigation/Feasibility Study, Westinghouse Plant Site, Adams County,Pennsylvania," March 29, 1988, Paul C. Rizzo Associates, Pittsburgh,Pennsylvania.

Rizzo Associates, 1988c, "Quality Assurance Project Plan, Revision 1,Remedial Investigation/Feasibility Study, Westinghouse Plant Site, AdamsCounty, Pennsylvania," July 27, 1988, Paul C. Rizzo Associates,Pittsburgh, Pennsylvania.

Rizzo Associates, 1989a, "Phase I Report, RemedialInvestigation/Feasibility Study, Westinghouse Plant Site, Adams County,Pennsylvania," June 12, 1989, Paul C. Rizzo Associates, Honroeville,Pennsylvania.

Rizzo Associates, 1989b, "Work Plan, Revision 1.0, RemedialInvestigation/Feasibility Study, Westinghouse Plant Site, Adams County,Pennsylvania," September 8, 1989, Paul C. Rizzo Associates, Monroeville,Pennsylvania.

USEPA, 1989, "Superfund Selection of Remedy," presented by USEPAHeadquarters Staff to American Council of Engineering Consultants,June 1989, St. Louis, Missouri.

ftl3QI5

TABLES

flR30ISi»7

TABLE SAP-1

SUMMARY OF PROPOSED PHASE II MONITORING WELLS

APPROXIMATE APPROXIMATEWELL SURFACE TARGETNUMBER ELEVATION DESCRIPTION ZONE ELEV.

(feet MSL) (feet MSL)

PMW-1A 544 Drill and Install 500Shallow Well

PMW-1B 544 Install Cased Well 350at Existing Boring

PMW-11A 555 Drill and Install 500Shallow Well

PMW-11B 555 Drill and Install 350Deep Well

PMW-12A 525 Drill and Install 500Shallow Well

PMW-12B 525 Drill and Install 350Deep Well

PKW-13A 530 Drill and Install 500Shallow Well

PMW-13B 530 Drill and Install 350Deep Well

PMW-14 510 Drill and Install 350Deep Well

flR30J5U8

TABLE SAP-2 ,

ANALYTICAL SUMMARY AMDDATA QUALITY OBJECTIVES

PHASE II

NUMBER FIELD EQUIPMENT TRIP DQOMEDIA OF SAMPLES DUPLICATES BLANKS BLANKS LEVEL ANALYSIS

Groundwater 2 3 2 2 2 IV(a) COI(b)

Soil 10 1 1 0 IV COI

Surface Water 2 I 1 0 IV COI

a. DQO Level IV - CLP analysis.b. COI - Trichloroethene; 1,1-Dichloroethene; and 1,1,1-Trichloroethane.

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APPENDIX A

SELECTED REFERENCES

AR30I555 Hi30IS

WHAT HAS GONE WRONG

IntroductionMany countries such as Canada, where the authors of this

editorial reside, are far behind the United States in legislation andregulation of ground-water contamination and corrective mea-sures. Canadians should take advantage of experience in theUnited States in these matters. The purpose of this editorial is toanalyze and discuss the main issues to direct attention to what weconsider grave deficiencies and possible improvements. The UnitedStates is nearing the* end of a decade in which much legislationpertaining directly and indirectly to ground water has beenenacted, most of which has been in operation for some time. Incomparison to nearly all other industrialized countries, thestringent nature of much of the U.S. legislation is exceptional. Thelegislation (especially the federal CERCLA and RCRA Acts) hasresulted in an increased awareness of ground-water contamination

by R.. Allan Freeze* issues in the United States and greatly increased expenditures onand John A. Cherry0 sita investigation, ground-water monitoring, and remediation.

These increases far exceed those in other industrialized countries,even when factors such as population and ground-water usage aretaken into account.

In this editorial we reflect on the general state of affairs inthe legislation-driven effort by the United States to controlground-water contamination and related. problems of waste dis-posal. It. is a reaction to observations that we have made ofCERCLA and RCRA projects in the United States and to thestrikingly different situation encountered in Canada. In ouropinion, much has gone wrong with the efforts resulting from thewell-intentioned legislative program south of our border. One can-not say this for Canada, because in Canada there has been littlelegislative effort, and therefore little to criticize except that lackof effort Legislative jurisdiction on ground water in Canadaresides primarily with the provincial governments, which generallyhave minimal ground-water legislation, and even less enforcementIn domains where the Canadian federal government does havejurisdiction, the accomplishments have also been limited. In theUnited States, changes need to be made so that more is achievedin the 1990/s than has been the case in the 1980's. In Canada, thefederal government and the provinces need to move toward newlegislation so that the deterioration in ground-water quality doesnot continue to go unchecked. For both countries, reflection onthe current situation in the United States is timely because eachcountry has so much to learn from these recent experiences.

Our comments are meant to be generic in nature. WhileRCRA and CERCLA are the most visible U.S. regulations thataffect ground water, they are certainly not the only ones. Thereare NRC regulations with respect to nuclear waste. There are many

'Professor, Department of Geological Sciences, University of BritishColumbia, Vancouver. British Columbia. Canada V6T 284.

bProfessor, Department of Earth Sciences, University of Waterloo,Waterloo, Ontario. Canada N2L 3G1.

' 458 A R 3 0 I 5 5 6 Vol. 27. No. 4-GROUN 1989

state and local regulations. There are regulations that involveground-water quality that do not arise in a waste-managementcontext. We encourage readers from ERA and other regulatorybodies to recognize that our comments are not directed at anyspecific agency or law but instead represent a general concern on abroader front.

If, as we believe, environmental legislation is not workingwell, there are several directions one might look to see what hasgone wrong. The regulations themselves may be faulty. The admin-istration of the regulations may be unfair. The waste generatorsmay be uncooperative. The legal response to the regulations maybe inappropriate. The technical response may be inefficient. Thepolitical influences on the process may be unwelcome.

We believe that there are problems in all of these areas, andthe purpose of this editorial is to try in a fair and objective mannerto reduce impediments to success in each of these areas as we seethem. While we have some general recommendations to offer, wedo not purport to have the entire solution. However, we doattempt to present the issues in a manner that may attract theattention of legislators in the United States and Canada to thetechnical and economic issues that have to be addressed if theproblem of ground-water contamination is to be dealt withrationally.

Regulations: The Legislators and Their AdvisorsRegulations should be comprehensive, logical, practical,

politically acceptable, cost-efficient, simple to administer, and fair.Much of the legislation in the United States designed to protectground-water quality fails to meet one or more of these criteria.

Take fairness, for example. It seems patently unfair to makeenvironmental legislation retroactive as is the case for theCERCLA legislation. As individuals, most of us would feelextremely hard done by if we were penalized for something that isillegal now, but wasn't when we did it, particularly if it was com-mon practice of the time. Representatives of waste-generating andchemical-use industries feel the same, and the loss of goodwillbetween industry and the legislators may ^ outweigh the value ofany cost recovery that can be achieved. In addition, there is a lossin credibility, in that industry now feels that it has no protectionagainst future legal action even if it meets current environmentalstandards. It is unlikely that cooperative compliance can beachieved in this climate of mutual suspicion. Of course, it could beargued that the world is unfair. Furthermore, the retroactivenature of the CERCLA legislation has resulted in some positiveresponses that perhaps would not have been achieved with anyother form of legislation; this issue is discussed later in thiseditorial.

The practicality of much of the current ground-water-qualitylegislation can also be questioned. Most of this legislation waspromulgated in the early heady years of the environmental move-ment. In many cases it was designated with little hydrogeologicalinput, and without recognition of the true complexities of the

459

problems. There is a tendency, especially in legisla- In summary, future legislation should be moretion promulgated in state and lower jurisdictions, cognizant of available technology, more flexible into set unrealistic compliance goals. In some cases, its technical requirements, and more applicable toit seems that performance standards are set at nonpoint sources and DNAPL migration.detection level, and as detection levels come down,so too do compliance standards. In some cases,state legislators are considering zero concentration Technical Administration of Regulations:as a standard for some fairly ub -.uitous contami- The Regulatorsnants. The public demand for complete remedia- Even when good clear legislation is in place,tion of contaminated ground water must be and more importantly when it is not, there istempered with practicability to clean up sites and usually a need for interpretation of the terms ofwith the available technology to monitor perfor- the law as it applies at particular sites. This taskmance. Laws that do not take such issues into tends to fall on the shoulders of individual officersaccount lead to wasteful expenditures because of of the regulatory agencies. In our experience, welack of decision-making discipline within a context have often found that the response of regulatoryof reasonable and achievable priorities. They also officials to findings at field sites is insufficientlybreed cynical disdain for the legislative process in flexible to allow field investigations to take theirthe technical community. proper course. For example, overreaction to appar-

We are also of the opinion that many of the ent "hits," which may be false positives, or whichlegislative packages are too rigid in their technical may be due to the difficult technical protocolsrequirements. Every site is different and every required when drilling through contaminatedhydrogeological environment presents special ground, is now causing many contractors to designcircumstances. Specification in the regulations of inefficient site-investigation programs in order tosuch details as the number and location of moni- avoid even the possibility of such an unexpectedtoring wells, as is the case with the upstream-down- hit early in the program. In a more reasonablestream guidelines in the current RCRA regulations, world, the results of drilling and measurementis ill-advised. Even the terminology of the law, if programs would be interpreted within the contextnot carefully thought out, can lead to impractical of accepted hydrogeological models. This is not tointerpretations by regulatory personnel. Some stats say that unexpected hits should be allowed to goregulations that require monitoring to protect the unexplained, but reasonable hydrogeological inter-"uppermost aquifer" have led to meaningless inter- pretations should prevail.pretations at sites that do not have layer-cake stra- As with the regulations themselves, we alsotigraphy. Strict adherence to the regulations can be feel that the administration of regulations is oftencounterproductive in that it may lead to monitor- too rigid. There is a need for site-specific interpre-ing networks that do not offer early warning of the tation, where a variance from the letter of the law,most likely modes of leakage. but not the spirit, might well be in order (consider.

Perhaps our greatest concern with respect to for example, trying to apply rules intended formany of the regulations is that they may have been saturated systems at a sits with a very thick unsatu-written to solve the wrong problem. Most legisla- rated zone, or rules intended for aqueous contami-tion was designed to combat pollution from man- nation migrating from a surface source beingaged point sources such as municipal landfills and applied where contaminants are actually migratingindustrial waste-management facilities. The greatest from a DNAPL pool situated deep in the ground-threat to ground-water quality may well come water system). It may be that highly placed offi-from nonpoint sources associated with agricultural cials in the regulatory agencies are loathe to allowfertilizers, herbicides and pesticides, and from too much flexibility in their field offices becauseunmanaged point sources such as machine manu- they recognize the widespread inexperience offactoring and repair shops, dry-cleaning shops, many of their junior officers. There is strongphoto-processing plants, electronics plants, other evidence that many talented young hydrogeologistsindustrial concerns, and domestic or communal working in a regulatory rola are quickly hired awayseptic systems or leaks in sewer lines. In addition, by engineering firms representing the wastemost of the legislation predates our emerging generators, once their talents are recognized duringunderstanding of the subsurface behaviour of the regulatory process. This is a serious problem indense, nonaqueous-phase liquids {DNAPL's), such its own right, in that it leads to an adversarialas chlorinated solvents, coal tar, creosote, and PCS process with most of the technical talent on oneoils. In cases where ONAPL's are prevalent and side. In the long run, an unequal adversarial processhydrogeological conditions are perverse, it might can lead to poor-quality decision-making, frombe possible to meet all the legal remedial require- which either underprotection or overprotectionments in current law without decreasing the long- could result. We urge regulatory agencies to keepterm potential for regional ground-water contami- their salary structures competitive with the privatenation. sector and to provide a creative and challenging

46° ftB301558

workplace in order to ensure that they can hold on To summarize, we believe tnat regulatorsto talented technical people. must develop greater flexibility in their interpreta-

More important than any of the issues yet tion of environmental legislation, significantlymentioned is the stifling effect of the current reduce the scope of their QA/QC procedures, takequality-control/quality-assurance procedures (QA/ steps to keep on board good technical people.QC) required by regulatory agencies. Over and over examine their unwillingness to consider perpetualwe have seen contractors' progress toward remedia- care as a remedial option, and improve their systemtion at field sites reduced to a crawl under the for prioritizing remedial sites.weight of QA/QC paperwork. In some cases, thesituation has become so ludicrous as to actually Legal Response to Regulations: The.halt technical work in the interests of bureaucratic Generators and Their Lawyerspaper-shuffling. We recognize the need for good Much of the current environmental legislationaccurate ground-water data, and for a certain level sets up an adversarial legal system in which wasteof accountability, but the current situation is one generators from the chemical and nuclear industryof immense overkill. A reduction in bureaucratic are pined against regulatory officials whose task isreview is imperative if progress is to be achieved on to protect society against environmental degrada-ground-water cleanup. We suspect that the primary 'tion. It is now common for both sides to be repre-motivation behind intensive QA/QC lies in the fear sented by legal teams.of litigation down the road. Reduction in QA/QC It is important that technical personnel recog-requirements must go hand-in-hand with policies nize that the lawyers operate in a different worldthat lessen the likelihood of trying to solve from scientists and engineers. Their objectives aretechnical problems in the courts. not the same as those of the engineer, who for the

Next, we rais-: questions about the administra- most part, is seeking an optimal solution. In ourtive response to various technical alternatives for justice system, the lawyers' role is clearcut: theyremediation. On one end of the spectrum, there are represent their clients' interests. Their view of thecases where ground water has been assaulted with best solution, and of the best way to achieve it,contaminants from many sources over long periods may differ from that of the scientist or engineer.of time, where potable ground-water aquifers are We have begun to see a disturbing trend; we oftennot at risk, and where remediation is unlikely to be see technical programs of investigation controlledsuccessful. In such cases, a no-action or almost-no- by the needs of the legal team. This approach leadsaction alternative should be considered. Wasting to a closed, uncooperative atmosphere, in whichmoney in attempts to clean up such sites diverts stonewalling as to the known facts and interprets-resources from sites where cleanup is feasible and tions becomes more common. As this trendneeded. We are even more worried about the other becomes increasingly evident, it will produce aend of the spectrum. In particular, we are con- public perception that scientifically based solutionscerned about the apparent unwillingness of regula- are lost in a labyrinth of legal games. This develop-tory agencies to consider perpetual care at sites ment cannot possibly promote environmental pro-where ground water has become contaminated. We tection.believe that in many cases perpetual care, in the In some countries, environmental legislationform of pumping, injection, and monitoring in allows for a negotiation approach rather than a cut-perpetuity, may be the only viable remedial and-dried setting of standards. Such negotiationsapproach. An unwillingness to consider this option also involve legal input but perhaps in this caseis driving contractors to propose quick-fix remedial such input would avoid the high costs that oftenalternatives that are not cost-efficient and are not result from an adversarial climate. There may be alikely to work. greater role for environmental mediation, in which

There seems little question about regulatory a mediator attempts to bring the sides togetherdedication at the siting and permitting stage of short of a courtroom showdown.waste-facility development. But we worry aboutdown-the-road enforcement of environmental per- Technical Response to Regulations: Engineeringformance standards. Enforcement is expensive and Firms and Their Hydrogeological Consultantsin most legislative jurisdictions, funding for this Engineering firms that contract with wasteexercise is woefully inadequate. As a result, regula- generators and/or regulatory agencies to carry outtory agencies too often focus on sites where the the technical investigations at new or remedialprincipal responsible parties are large, financially waste-management sites are not free from responsi-stable corporations for which cost recovery is bility in this catalogue of what has gone wrong.feasible (the so-called deep-pocket syndrome). It Neither are the individual ground-water scientistsseems that sites are being prioritized on the basis of and engineers who work for such companies orthe probability of successful cost-recovery rather who consult to them.than on the probability for prevention of excessive First, there is the age-old problem of makingadverse impact on health and the environment. the technical aspects of the project fit the needs of

461

the client. In most engineering endeavors, both individual engineers and hydrogeologists carefullyclient and consulting firm have a high cegree of examine their ethical conduct to ensure that theytechnical expertise, well-suited to the project at are bringing RI/FS studies to closure in an efficienthand. In the waste-management field, this is not manner, that they are providing objective hydro-a;..ays the case. While the situation is fast improv- geological interpretation undistorted by theiring, it is nevertheless still quite common for chemi- clients' legal needs, and that they are contributing .cal or nuclear firms with waste-management prob- to designs that not only meet the regulations, but x^xlems to have little hydrogeological understanding also protect the safety, health, and welfare of theor expertise. Some engineering firms appear to take public.advantage of this situation by recommending fieldinvestigations and modeling studies that seem urv Political Influences on the Process:ending. We are all familiar with remedial investiga- The Citizens and Their Lobbyiststions (Rl), and then feasibility studies (FS), Phase It is widely recognized that decisions that are1, and then Phase 2; or Phase 1A, Phase 18, and optimal in some sense for society as a whole willthen Phase 2. It is apparent that there is sometimes not be optimal for all the individuals in the society.no incentive for the consulting firm to close their As a result, we have LULU's ("locally unwantedinvestigations. Fear of liability may also play a role land uses") and the NIMBY syndrome ("not in myhere, and consulting firms may recommend addi- backyard!"). The existence of LULU's and thetional work largely to protect themselves against NIMBY syndrome lead to special interest groupsfuture lawsuits. To some degree, the responsibility and lobbyists who work on the;r behalf. Suchfor a failure to close lies with the regulatory agen- groups often become the bane of generators andcies, who often have political reasons to postpone regulators alike. It is sometimes difficult to remem-decisions, but we believe that the engineering com- ber that people resist LULU siting because theymunity itself has an obligation to make decisions fear a decline in their property values, or worseabout siting or remedial design at the earliest yet, disease and health decline, and even death.possible moment in the investigative process when These fears are not irrational, and policymakerssuch decisions can be made in good faith. must accept peoples' fears as a valid part of policy-

As a second issue, we note that engineering making. Successful citizen suits are making itfirms and individual hydrogeologists, when placed impossible to ignore these fears. Nevertheless, therein a truly adversarial position between waste gener- is no question that politically strong groups canator and regulatory agency, or between one or overwhelm the politically weak, and the result ismore potentially responsible parties in a cost- often bad siting. Study after study has shown that > jrecovery process, often try to serve their clients the best routs to clean ground water is through —'too well. We worry that hydrogeologists are taking good hydrogeological siting, not clever engineeringon the style of lawyers. The bending of hvjrogeo- design. Regulatory agencies must be willing tological interpretations to meet the legal rather than defend technically sound siting decisions againsttechnical needs of a client is unethical and more of political pressures. On the other hand, the politicalit is creeping into our business than most of us system must begin to examine what types of bene-would like to see. fits can be offered to communities to offset the

There is another ethical issue that engineers unarguable social costs of hosting waste-manage-and hydrogeologists must face. All engineers func- ment facilities. Under the SARA amendments totion under a coda of ethics; the first fundamental CERCLA, it is required that each state be able tocanon in the ASCE Coda of Ethics states that engi- certify that it has adequate capacity for the dis-neers shall hold paramount the safety, health, and posal of the next 20 years' hazardous waste or thewelfare of the public in the performance of their state will lose all Superfund monies. This isprofessional duties. In the absence of regulations, a Congress' attempt to overcome the NIMBY syn-design engineer would presumably prepare designs droma at a state level.for a waste-management facility that are in keeping We also nota at times an unwillingness on thewith his interpretation of the code of ethics. How- part of regulatory agencies to differentiate betweenever, with the detailed regulatory systems that are good and bad corporate citizens during the adver-now in place, we believe that most design engineers sarial remedial process. In such cases they remainnow feel that they have satisfied their ethical obli- hostile to cooperative waste generators in order togations if they meet the regulatory requirements. assuage political opinion. In our opinion, this is anIn the U.S. high-level nuclear waste program, for unethical stance for a public agency. They shouldexample, there is no question that DOE design instead take the more difficult route of attemptingguidelines are driven by NRC regulations. If this is to explain to the public interest groups in a partic-a correct approach, then an engineering ethic ular community how the response of their particu-cannot be viewed as morally absolute; it is a lar corporate nemesis compares with the less coop- ,function of the regulatory climate. erative responses at other sites. If cooperation on V._s

In summary, we feel that it is imperative that the part of waste generators is not rewarded, it is

462&R30I560

unlikely that they will continue to take such a not to say that CERCLA sites have not impactedstance in future dealings with regulatory bodies. some important aquifers, but rather that in the

Another issue with political overtones con- broad context of the nation's water supply,cerns the role that is to be played by nonregulatory CERCLA is less important than is sometimesagencies. In the United States, the U.S. Geological claimed. ••Survey and other federal and state geological, agri- Second, attempts at aquifer remediation,cultural, and water-resource agencies have become where the goal has been to return a water-supplyinvolved on one side or the other in some of the aquifer to a state where its water meets drinking-adversarial procedures. In our opinion, such water standards, have almost without exceptionagencies are ill-suited for this role and may be -n been a failure. If not an outright failure, they haveconflict of interest. Their involvement usually leads made so little progress that expectation is forto difficulties on all sides, not least within the success not to be achieved in this century andagencies themselves. We urge such agencies to re- maybe not in the next one.examine their policies with respect to tneir involve- Third, the cost of Superfund RI/FS sitement in adversarial environmental matters. studies is generally large (millions of dollars is not

It is right and proper for political influences uncommon). The cost of implementation ofto play a role in environmental decision-making, ground-water remediation that prevents off-sitebut it is equally important that this role not be contaminant migration is also large, generally onallowed to overwhelm siting decisions or to subvert • the order of tens of millions of dollars. It is esti-the technical adversarial _ ocess. mated that the CERCLA legislation will eventually

cause a total of about 300 billion dollars of expen-What We Have Learned diture by industry and an equal amount by govern-

The intended outcome of the ground-water- ment. For such investment, very little of thequality legislation put in place in the United States nation's exploitable ground water will be protectedin the last decade, whether stated explicitly or im- or improved.plicitly, seems to have been zero contamination at Fourth, new technologies for aquifer remedia-new waste-management sites, and a return to pris- tion have generally contributed little to reducingtine conditions at remedial sites. It is certain that these costs or providing permanent solutions. Purgethis outcome has not been achieved, and it now wells and aboveground-water treatment, occasion-appears likely that it is not achievable, at least at ally coupled with cutoff walls, and various combi-DNAPL sites. It is necessary for regulatory person- nations of excavations, soil treatment and soil caps,nel to inform legislators of this fact, and for legisla- more or less as used in the 1970's, remain primetors to inform the public. Current public expecta- items on the menu for the 1990's. There is littletions with respect to remediation are quite likelihood that this situation will change drasticallyunrealistic. What is achievable, and what is being in this century, as a result of scientific or techno-accomplished at most sites, is a reduction in logical breakthroughs. In general, possibilities forenvironmental degradation and/or health risk to a cost-effective aquifer cleanup are limited at mostlevel that is in some sense "acceptable." The level sites because of factors related to geological com-of risk that is deemed "acceptable" is something plexity, compounded fay difficulties imparted bythat is decided in the political arena, but hopefully DNAPLs or LNAPLs.in a political arena that is technically well- There is now little doubt that at sites whereinformed. DNAPLs are the problem, the local ground-water

From a hydrogeological perspective, the zone has terminal cancer. A cure, in the form ofmajor outcome from the first generation of legisla- returning aquifer quality to drinking-water stan-tion has been the creation of a large suite of field dards, is unachievable at almost any cost. Atlaboratories in the form of large-scale remedial DNAPL sites, costs are going up and aquifers areactions, which are essentially research experiments not much improved.to see how cleanup can be accomplished and what From these points, a conclusion follows: thelevel of cleanup is attainable. This outcome was cost of aquifer protection by minimizing possibil-undoubtedly unintended by the legislators, but it is ities for spills, leaks, or improper disposal ona positive outcome in that it will lead to a more aquifers is generally much smaller than the cost ofrealistic second generation of legislation in due studying, designing, litigating, and remediatingcourse. aquifers after contamination in the aquifer is

Since the CERCLA (or Superfund) legislation found. There is an urgent need for a shift in totalwent into effect in 1980, much has been learned as societal expenditures. We should move away froma result of studies conducted at Superfund sites, high capital-cost, quick-fix remedial solutions, andand also during this period, at many other sites. recognize the need for long-term operationalFirst, a significant number of Superfund sites are investment. We should move away from thenot situated on or near major aquifers that are sole- present overemphasis on attempts at correction ofsource or significant-source water supplies. This is ground-water problems caused by actions of past

463

>*•*;

decades, and the associated legal costs of guilt- strongly influenced by the knowledge that largeestablishment and punishment for these past sins, future penalties will be the results of current care-and move toward investment in current water- lessness.resource protection by. the prevention of leaks. To summarize our views, we worry that thespills, and improper disposal. In this way, invest- current technical legal and political administration ^ment today will reap benefits tomorrow. This is of ground-water-contamination legislation in the v Jmuch more easily said than done because our United States is subverting proper scientific ^^industrial society uses so many chemicals from methodology and good engineering practice. Whatwhich widespread, long-term contamination can is needed now is for changes in legislation so thatresult from very small spills or leaks. The difficulty the second generation legislation will be moreof ground-water protection bodes poorly for much realistic and flexible, less dependent on legal adver-success unless the major protection effort is sarial action, less open to political interference, andfocused on those aquifers most worthy of protec- less encumbered by bureaucratic red tape. Thetion. The classification and prioritizing of aquifers legislation should be aimed at protecting thoseis a job worth pursuing with urgency. aquifers that are deemed worthy of the cost. We

Perhaps the major achievement of the urge a move away from the blanket cleanup of allCERCLA legislation is that it has caused large subsurface contamination to a policy that focusescorporations to become emphatically aware that on protecting aquifers that constitute valuablethe improper disposal and accidental spillage or water supplies and remediating sites where signifi-leakage of industrial chemicals, either in product or cant health-risk reduction can be achieved. Wewaste form, can result in remedial and legal costs suggest less emphasis on punitive assessment ofthat can be immense and that can impact signifi- past practices and more emphasis on proper storagecantly on the year-to-year corporate "bottom-line" and disposal today to ensure environmental qualityfor many years, in some cases even to the point of tomorrow.jeopardizing the financial viability of a company.The fact that the legislation is retroactive has . . . . .caused many large corporations to realize that inthe future, avoidance of such financial liabilities A Allan Fmat has bem , Professor at Univtrsityshould be accomplished by adherence within the of British Columbia since 1969. He received degrees in Geo-corporation to the highest technical and scientific logical Engineering from Queens University in Ontario andstandards, regardless of whether or not these the University of California. Berkeley. He has bean Presi-standards exceed those specified in current legisla- dent of the Hydrology Division of the American Geophysi- v>tion, or are otherwise different from current cat Union and has received awards for his ground-water ^ ^legislation. research accomplishments from the Geological Society of

It is now realized that legislation generally America, the American Geophysical Union, and thechanges from decade to decade and that what is an Canadian Geotechnical Society. He is the coauthor, withacceptable corporate environmental achievement J2>"ChZ'Y'of ** ***** Gf0undv"ter (*"•*<»•»*»,one year in the eyes of legislator, can become urv S*j "ZZS SSSSTS"S!acceptable ,n the next. CERCLA has caused many JBiftwfc*I decisiofMTtaking £ sposlland relatedlarge corporations in the United States to adopt ground-water issues such as site selection, monitoringmuch higher internal ethics and standards with design, and remediation.respect to ground water and other environmental John A. Cherry has been a Professor at the Universityissues. From this approach these corporations hope of Waterloo since 1971. He has degrees in Geological Engi-that they will never again be caught by retroactive neering from the University of Saskatchewan and the Uni-legislation. varsity of California at Berkeley and in Hydrogeology from

It may be time for an amnesty for actions f*» »*"rrtx of Illinois. He has received awards fortaken long ago when such action* were generally 'ground-water research accomplishments from the Geoiogi-accepted practice. But such amnesty should be t'?00' * T? • ™*«y*? Uni°n:coupled with very large re atc ena.ties for l,XS tSe ^any current malpract.ee on the part of waste gener- „, w, Oinctor of *, Institut9 for Groundwter Researchators. There may be some industrial entities who # Waterloo. His current research and consulting interestshave not learned the lessons of the 80's. We must pertain to the behaviour and monitoring of industrialensure that their present-value economic decisions chemicals in ground water and on assessment of hydro-with respect to waste-management practices are geologic factors in site remediation.

464ftiSOI5S2

29.0

PRACTICAL LIMITS TO PUMP AND TREAT TECHNOLOGY

fOR AQUIFER REMEDIATION

by

Clinton W. Hall

Robert S. Kerr Environmental Research LaboratoryAda, Oklahoma

ABSTRACT

Effects of tailing, sorptfon, and residual immiscible fluids on time required forpump and treat remediation of ground water are discussed. Major items discussed arethe tailing effect on contaminant removal time; sorptfon effects on contaminantremoval time; and effects of NAPLs on contaminant removal time.

ftftS015-63

29.1

-PRACTICAL LIMITS TO PUMP AND TREAT TECHNOLOGY

FOR AQUIFER REMEDIATION

Until recent years ground water contamination was generally "managed" by abandonmentand relocation of the well or well field to an uncontaminated area. Indeed theconventional philosophy was that once contaminated, an aquifer could not be restoredto its pristine condition and prevention was believed the only cure. Today bothpublic attitudes and environmental law require aquifer remediation, and enormoussums will be spent in coming years attempting to clean-up contaminated ground water.

While some success has been demonstrated with in-situ biorestoration, if one ischarged with restoring a contaminated aquifer today, the procedure of pumpingcontaminated water to the surface for treatment and discharge is most often theslate-of-practice technology. The perceived success of pump and treat technology canbe misleading if the hydrology and contaminant characteristics at the site are notadequately understood. A failure to understand the processes controllingcontaminant transport can result in extremely long pumping periods and,consequently, costly and inefficient remediation.

Ground-water contamination problems vary greatly '•" all regards, including theirsize and depth, the nature of the geology, and the characteristics of thecontaminants, as well as their source. A thorough understanding of all of thesefactors is critical in developing cost-effective remediation technology and definingthe proper role of pumping and treating within a remedial action plan.

To better put in perspective the ramifications of contaminant behavior in aquifersystems to a pump and treat project, it is helpful to develop a site scenario byassigning the conditions of size, geology, and contaminant type. For this purpose.assume that the area of ground-water contamination is ten acres; the aquifer has a

29.2

thickness of about 55 feet; the water in storage amounts to 30 percent of theaquifer's volume; and the contaminant is salt water. Under these conditions, itwould be possible to exchange the water in this ten-acre plume in about a year bypumping at a rate of 100 gallons per minute.

2For example, 10 acres x 43560 ft /acre x 55 ft x 0.3 water filled porosity x 7.53gal/ft - 365 days/yr x 24 hrs/day x 60 min/hr x 103 gal/mi n x 1 yr.

Indeed, it appears that pumping would solve this problem, under these conditions,where the contaminant is very soluble and is not retained on the subsurfacematerials. In reality, it may be necessary to pump for two or three or more yearsto reach an acceptable salt concentration due to the "tailing" effect often observedin these types of remedial actions.

Tailing is the slow, nearly asymptotic decrease in contaminant concentration inwater flushed through contaminated geologic material. Tailing may be caused byseveral phenomena. In the simplest case of a highly soluble non-retainedcontaminant, tailing is due to contaminant migration into the finer pore structureof the geologic material. These finer pores then contain water and contaminantsthat are only slowly exchanged with the bulk water present in larger pores, andtailing is a result. It is the water and contaminants in the larger pores that ismobilized during pumping.

The problem in trying to remove many of the man-made and natural organic compoundsfrom ground water is that they tend to preferentially sorb to the organic andmineral components of the aquifer material. Therefore, when water is removed bypumping, the predominant amount of the contamination remains behind on the aquifer<solids. Obviously, removing the aquifer material instead of the water is not usuallya feasible alternative. The ratio of sorbed to dissolved contaminant is a property

fct301§65

29.3

specific to a particular contaminant and a particular aquifer material. Once sorbed.contaminants will desorb to reestablish this ratio as cleaner water is passedthrough the system and thus be removable by pumping. However, research has shownthat a fraction of the sorbed contaminant is only slowly released into the water.This slow, desorptive release acts in concert with slow contaminant release from thefine pores, discussed above, to increase the tailing effect, and the time requiredfor remediation.

A contaminant that sorbs to the soil materials moves slower through the soil thanone that does not react with the soil solids. The amount of decrease in mobility isproportional to the ratio of the amount in solution versus the amount sorbed to thesoil. This ratio is often described as a linear partition coefficient (k .) by theequation

" Cs

where C - the mass concentration in the aqueous phase, and • V _ x21C « the mass concentration associated with the solid phase.

Based on this equation it is possible to show that the ratio of the velocity of thewater (V) to the velocity of the contaminant (V ) is

where p is the bulk density of the soilp is the density of the water3e is the volume fraction occupied by the water.

29.4

if we consider-a similar scenario as above where the contaminated area is 10 acres(660 ft by 660 ft), the aquifer is 55 feet thick and flow is from one vertical faceto the opposite vertical face with a Volume discharge of 100 gpm and a porosity of0.3, the interstitial velocity of the water would be approximately 660 ft/year andit would take water approximately one year to pass from one end of the contaminatedarea to the other. If the bulk density of the soil is 100 Ib/ft , the density ofwater is 62.4 Ib/ft . and the soil partition coefficient is 0.75 (unitless), then itwould take 5 years for the pollutant to traverse the length of the plume, and pumpand treat might still be quite feasible.

The problem of site remediation is complicated exponentially, however, if thecontaminants are themselves constituents of a water-insoluble oily phase such asgasoline, heating oil or jet fuel. In this case, the oily phase will become trappedin the finer pore spaces by capillary forces and cannot readily be pumped out. Thisresidual saturation can result in a significant hidden source of contamination. Itis invisible to a monitoring well as only the dissolved fraction will be present inthe water that is withdrawn. Its benzene, toluene, and xylene components thenpartition or "bleed* into the passing ground water at a rate and to a concentrationwhich is characteristic of the contaminants of concern.

To properly appreciate the time required to remove the constituents of an oily phasesuch as gasoline by pumping, it is only necessary to return to the scenarioconditions developed above for salt water. However, it is necessary to includeterms for the partitioning of the compounds of concern to the residual oil. Therelative velocity of the contaminant now follows the equation

29.5

where p is the density of the oil. o is the volume fraction occupied by the oil,and k is the oil water partition coefficient. If the total porosity remainsconstant at 0.3 and it is occupied by a combination of water and oil it is possibleto construct a curve showing the amount of time required to reduce the concentrationof a contaminant by one half. In generating figure 1 it was assumed that thesoil:water partition coefficient was 0.75 and the oihwater partition coefficientwas 3000 for toluene and 11000 for o-xylene as reported by Bouchard, Enfield andPiwoni (1) for residual oil at a contamination site in Michigan. This is similar tothe values of partition coefficient for JP-4 fuel reported by Smith et al. (2) whichwere 2750 and 7080 for toluene and o-xylene respectively. Thus, from the figure, ifit took one year to exchange the fluid one time and 10% of the system were occupiedby non-mobile oil (residually saturated), then it would take thousands of years toremove toluene or o-xylene if no other processes were taking place.

One can be deceived in attempting to remove the components of gasoline by pumping atincreasingly higher rates since the concentration of these contaminants initiallymay appear to be reduced or even eliminated. This deception can result fromdilution, by bringing larger amounts of uncontaminated water into play; or bydropping the water table below the source of contamination, or both. It isimportant to understand that the contaminant cannot be removed faster than it isreleased into the passing ground water.

In any event, if the pumps are stopped for some period of time, the water solublegasoline components wiB again dissolve into the ground water and one will find thatthe contaminant concentrations have returned to their previous levels.

There is little doubt that pumping and treating ground water is a viable approach totaquifer restoration in some instances, particularly when the aquifer ishydrologically homogeneous and the contaminant or contaminants are highly soluble

29.6

and have little affinity for sorbing to the aquifer material. It may also haveutility when it is necessary to remove the more highly concentrated portions of acontaminant plume, or perhaps even a separate phase such as gasoline floating onground water. Some contaminants will also be removed when using wells to interceptcontaminated ground water. It will not usually be applicable to the removal of oilywastes or those synthetic organic compounds which tend to highly sorb to the aquifermaterial. There are many cases, especially where the contamination is very old,where the compounds have found their way into the finer pore structure of theaquifer where their movement back into the water phase will be very slow.

It is important to understand the processes that limit the effectiveness of pump andtreat technology in order to develop efficient and cost effective remedial actionplans. Continuing research to better understand these processes will permit a moreinformed selection and staging of alternative and/or complementary remedial actiontechnologies.

REFERENCES

1. Bouchard. D., C. Enfield, and M. Piwoni. At press. Transport Processes InvolvingOrganic Chemicals in Reactions and Movement of Organic Chemicals in Soils AmSoc. of Agronomy Symposium.

2. Smith, J.H., J.C. Harper and H. Jaber. 1981. Analysis and Environmental Fate ofAir Force Distillates and High Density Fuels. SRI 1614 Final Report ESL-TR-81-51!50p.

29.7

C 0)<U C-1 (U> 3X .-Ii oO JJ

SUPERFUNDSELECTION OF REMEDY

U.S. ENVIRONMENTAL PROTECTION AGENCY

Jun* 1889

SELECTION OF REMEDY

1. Statutory Framework2. Goals and Expectations3. Process4. Program Management Principles

1. STATUTORY FRAMEWORK

Original Provisions of CERCLA Require Remedies to be:• Protective of Human Health and the Environment• Cost-effective

STATUTORY FRAMEWORK(continued)

SARA Section 121 Added Mandates to:

- Attain the Applicable or Relevant andAppropriate Requirements of OtherFederal and State Environmental Laws

• Utilize Permanent Solutions and AlternativeTreatment Technologies or ResourceRecovery Technologies to the MaximumExtent Practicable fMEP")

• Employ Treatment that Permanently andSignificantly Reduces Toxictty, Mobility orVolume as a Principal Element or Providean Explanation as to Why Not

2. GOALS AND EXPECTATIONS

GOAL: Achieve Effective, Reliable Solutions that MaintainProtection Over Time.

EXPECTATIONS:• Protection Can Be Achieved Through • Variety of Means

• Treatment to Reduce Hazarda• Engineering Methods to Control Exposure• Combinations Expected Frequently

• Statutory Emphasis on Long-term Protection, Preferenceto Achieve Through Treatment

• Permanence Achieved in Degrees, Highest DegreesAfforded by Remedies that are not Heavily Reliant onLong-term Operation and Maintenance

• Ground Water Should be Restored to Beneficial UsesOver a Reasonable Period of Time

• Institutional Controls Often Supplement EngineeringControls During Implementation and as Part of Long-term Management

TREATMENT

Treatment is Most Likely to be Utilized on:

• Highly Toxic Waste• Highly Mobile Waste• Waste That is Several Orders of Magnitude

Above Health-based Levels• Liquids

CONTAINMENT

Containment la More Likely to ba Utilized Where:

• Sits* are of Extraordinary Size• Waste Material la Near Health-based Levela• Treatment Technologies ara not Feasible or Available• Treatment Would Result In Greater Rlak• Waste la Especially Difficult to Handla or Treat

3. REMEDIAL PROCESS

RemedialInvestigation

Scoping ProposedPlan

FeasibilityStudy

Lr

Record ofP*cteten

RemedialDesign

RemedialConstruction

REMEDIAL INVESTIGATION

Conduct RtW Investigation to Define theNature and Extant of ContaminationConduct Baseline Risk AssessmentConduct Treatabllity Studies

FEASIBILITY STUDY

Establish Remedial Action ObjectivesIdentify Hazardous Waste ManagementApproachesScreen Alternatives, as AppropriateConduct Detailed Analysis of EachRemedial Action Against Nine EvaluationCriteria

NINE CRITERIA

Threshold Requirements:Ovtftll Protection of Human Health and the EnvironmentAttainment of ARARs (or Waiver)imary Balancing Factora:

Long-term Effectiveness And PermanenceReduction of Toxlcity, Mobility and VolumeShort-term EffectivenessImplementablHtyCoat

Through Treatment

xilfylng Considerations:Statt AcceptanceCommunity Acceptance

A8SQ157-6

COMPARATIVE ANALYSIS

Identify Relative Advantages and Disadvantagesof AlternativesMajor Tradeoffs Often Include:• How much waste to treat•• Treatment process

• Type of management of waste and residuals• On-stte or off-site management• Risk levels (10'* to 10mr)• Confidence In remedy•• Implementation•• Long-term (permanence)

• Short-term impacts• Cost

FINAL REMEDY SELECTION

SCREENS:

PRIMARYBALANCINGFACTORS:

BALANCING:

v XKKKKKXKKKX OOOOOOOOOOO X

TMVReduction !•*••"•«•«

CtfMtlVMMS

4. PROGRAM MANAGEMENTPRINCIPLES

Early ActionsStreamliningStandardization of Program

EARLY ACTION

Objectives:

• Achieve Rapid Risk Reduction• Collsct Data Which Will Assist In Making

a Sound Final Rtmtdy Selection DecisionMethods:

Removal ActionsExpedited Response Actions

• Remedial Operable Units

STREAMLINING

Tailor the Scope and Detail of the RI/FS to Site Circumstances:• Only Collect Data Necessary to Evaluate

Alternatives and Support Design• Focus Alternative Development and Screening Early• Tailor Nine Criteria Analysis to Scope of Action• Tailor Documentation to Scope of Action• Collect Samples Necessary for Design During the

Public Comment Period on the RI/FS

EXAMPLE OF A GROUND WATERINTERIM ACTION

Ground Water Contamination• DNAPU In Ground Water- Plume Rapidly Moving• Potential Remedy Goals•• Clean up to Hearth Based Levels•• Plume Containment•• Maximize Contaminant Mass Removal

- Complex Hydrogeotogy Limits Confidence In WhichGoaKs) ara Appropriate

Selected Interim Action• Authorization to Pump Ground Water for Rva Ytars• System Designed to Contain Plume and Maximize MassRemoval. Will Determine Appropriate Goal In Five Years

• ROD la Straightforward

STANDARDIZATION OF PROGRAM

Selection of Remedy GuidanceRisk Assessment GuidanceARARs• Land Ban• ClosurePrototype Remedies/Generic RI/FSs

RR30I580