JV1ACCORPORATIONEnvironmental Services

Public Ledger BuildingIndependence Square6th and Chestnut StreetsSuite 872Philadelphia, PA 19106Telephone: 215-440-7340Fax: 215-440-7346

August 30, 1991

Mr. Frank VavraU.S. Environmental Protection Agency841 Chestnut StreetPhiladelphia, Pennsylvania, 19107

Subject: Hunterstown Road SiteContract NO. 68-W9-0005 (TES VIII)Work Assignment No. C03016Review Report of Phase II RI Report

Dear Mr. Vavra:

In compliance with our Review/Oversight work assignment, Dynamac issubmitting to you the attached Review Report of the Phase II RIReport, submitted to EPA by Paul C. Rizzo Associates in July of1991.

In general, we found no major inconsistencies as to form or contentin the Phase II RI Document. While differences regarding someaspects of the hydrogeologic interpretation may continue to bebones of contention, there is general agreement about the physicalnature of the ground water flow system, and flow directions. Inaddition, there is general agreement about the accuracy of the datasets compiled and presented in the Phase II RI Report.

If you have any questions or need for clarification, please call meanytime. Hope that you have a pleasant Labor Day weekend.

Yours truly,

David A. Schock, Hydrogeologist

cc: Ms. Donna McGowan, U.S. EPA Region III CERCLA RPOMr. Robert E. Stecik, Jr., Dynamac, Philadelphia OperationsMr. Kirk McCutcheon, Dynamac, Philadelphia

Corporate Headquarters: The Dynamac Building, 2275 Research Boulevard, Suite 500, Rockville, MD 20850-3;10306270£.00

DYNAMACCORPORATIONEnvironmental Services

Public Ledger BuildingIndependence Square6th and Chestnut StreetsSuite 872Philadelphia, PA 19106

Telephone: 215-440-7340Fax: 215-440-7346

August 30, 1991

Mr. Frank VavraU.S. Environmental Protection Agency841 Chestnut StreetPhiladelphia, Pennsylvania, 19107

EPA Contract No. 68-W9-0005Work Assignment: Hunterstown Road Site Phase II RI/FS Report

C03016

Dear Mr. Vavra:

Dynamac has reviewed the Phase II Remedial Investigation-Feasibility Study (RI/FS) for the Hunterstown Road Site in AdamsCounty, Pennsylvania, a report prepared by Paul C. RizzoAssociates, Inc., (PCR) on behalf of Westinghouse ElectricCorporation and submitted to the U.S. Environmental ProtectionAgency (EPA) in July 1991. This RI/FS study was required under theConsent Order with EPA dated March 10, 1987 (U.S. EPA Docket No.III-87-5-DC), and the objectives of this Phase II Study wereoutlined in the RI/FS Work Plans dated July, 1990, and October,1988.

With respect to the report format suggested in Guidance forConducting Remedial Investigations and Feasibility Studies UnderCERCLA (OSWER Directive 9355.3-01, dated October 1988), and themajor shortcomings of the Phase I RI/FS, as described in our letterreport of November 22, 1989, the Phase II report includes anextensive Baseline Risk Assessment chapter and a general thoughcogent discussion pertaining to Contaminant Fate and Transport.With respect to the aforementioned guidance document, relevantportions of the NCP, as described in 40 CFR Part 300, and the WorkPlan Objectives (July 1990), the Phase II RI/FS Report isreasonably complete, with the exception of an evaluation ofremedial alternatives, which is, in the instance of this project,being carried out as separate Feasibility Studies, to be undertakenduring and after the formal review the Phase II RI Report.

Comments on the interpreted hydrogeology of the HunterstownRoad Site as characterized in the Phase II RI/FS.

1. The interpreted direction of the shallow ground water flowdirection differs between that found on page 3-13 (west to

Corporate Headquarters: The Dynamac Building, 2275 Research Boulevard, Suite 500, Rockville, MD 20850-:

southwest)in the Physical Characteristics of the Site Sectionand that found on page 5-3 (south) in the Fate and TransportSection. This is a major discrepancy and needs eitherexplanation or correction.

2. The ground water plume associated with the lagoon is notdefined at depth (see Figure 4-3), nor is it defined northeastof the 100 ppb isopleth by any data points (see Figure 4-1).In addition, the high level of total volatiles found in HMW-5CL (>20,000 ppb) suggests that the associated water bearingzone, which appears to be different from that of the HMW-3AL,HMW-2BL and PW-1, is significantly contaminated and may needadditional recovery wells or additional monitoring wells.These wells should be considered in the design phase.

3. The contaminated ground water plumes associated with the twoDrum Burial Areas (Figure 4-2) may require additional datacollection (perhaps additional wells) during feasibilitytesting and/or design of the remedial system to more preciselyidentify the center of contamination in the vicinity of theinferred source. This would be necessary to determine whereto place recovery wells and any additional monitoring wellsassociated with the remedial design.

4. The contaminated ground water plume associated with DrumBurial Area No. 2 is undefined to the northeast (see Figure 4-3).

5. The contaminated ground water plume associated with DrumBurial Area No. 1 is undefined at depth (see Figure 4-3).

6. According to Figure 1-3, the Gettysburg waterline extendsalong Hunterstown Road to the northeast edge of the site map.Given that the two homeowners farthest to the northeast (seeFigure 2-11) on Hunterstown Road (Lott and Tressler) indicate(see Table 2-1) that they do not have public water, how fardoes the public waterline actually go? Is Figure 1-3 anaccurate representation of the extent of the public waterline.

7. The relatively low heads (between 480 and 490 feet, MSL) inthe deeper monitoring wells associated with the lagoon plume(plus the steeper hydraulic gradients inferred by PCR), incomparison with those found northwest of Hunterstown Road (seeFigure 4-3), were addressed in the Work Plan, but notdefinitively accounted for in the Phase II RI Report. Theyshould be carefully considered in any ground water remedialdesign, including considerations involving the placement ofrecovery wells in a pump and treat system and any additionalmonitoring wells.

Comments on Data Validation for Hunterstown Road Phase II RIReport:

AR3Q6275

A review of the Hunterstown Road site Data Validation reportprepared for PCR by the Radian Corporation for incorporation intothe Phase II RI Report of July 1991 (Appendix I) was undertaken byDynamac. The Radian Data Validation Report, nor any of thedocuments presented to Dynamac for review, included the laboratoryQC forms. As such, upon direction from EPA, Dynamac's review waspredicated upon an acceptance of the validity of the RadianCorporation's Data Validation review, which was carried out usingthe QC reports, and concentrated on the objective of verifying theadherence of the data validation procedures to USEPA Region IIIguidelines.

The review showed that the validation procedures performed byRadian Corporation, in general, adhered to USEPA FunctionalGuidelines (1988) and to Region III modifications. However, minordeviations were noticed. These are:

1. The holding time for volatile organics analyses wasstated as ten days in the Phase I soil data validation summaryof the Hunterstown Road site. Region III modifications, June1988, states that "the reviewer may wish to flag solid sampleresults as biased low when holding times are greater thanseven days". Based on the data provided, it was not possibleto verify whether the validation process based on ten daysholding time may have only affected the reported Sample No.1348742, or it may have also affected other volatile analysesof soil samples collected in Phases I and II of the site. Ifthe holding time for other samples was less than ten butgreater than seven days, these samples may be flagged asbiased low.

2. The holding time for semivolatile organics was stated asten days in the Phase I data validation summary of theHunterstown Road site. USEPA Functional Guidelines, June1988, states that "samples must be extracted within seven days... if holding times are exceeded, flag all results asestimated (J) and sample quantitation limits as estimated(UJ)". Based on the data provided, it was not possible toverify whether some of the base neutral/acid results shouldhave been flagged as estimated.

Both of the field and the laboratory audits of sampling activitieswere thorough.

In conclusion, this review agrees with the Hunterstown Road sitePhase II RI Report Data Validation Report which concluded that thedata as qualified is acceptable for use to meet the RI objectives.

Split Sample Analysis Associated with Hunterstown Road Site PhaseII RI Report:

Split-samples from both soils and monitoring wells were sampled by

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Dynamac for EPA. This was completed in order to compare analyticalresults with those of Paul C Rizzo (PCR), the PRP consultant. Thesplit sample data (attached Table 1) show that while some PCRsamples had values almost identical to those of EPA, most splitsamples showed some discrepancy between EPA and the PCR laboratory,Lancaster Labs.

For example, Boring SS-B4B-01 showed metals in the PCR sample atlevels about three times higher than EPA's for all four parametersthat were analyzed by PCR. Boring SS-HTB-35 had total 1,2dichloroethene levels 3.5 times higher in EPA's sample. Monitoringwell HMW-16 showed trichloroethene at levels of over a hundredparts per billion higher in EPA's sample.

The following is a summary of the split samples (EPA) and how eachcompare to the corresponding PCR samples.

Soil Samples

SB-HTB-37-01 - Of the compounds detected, acetone was identical,while methylene chloride (MC) was higher in the EPA sample.

SB-HTB-37-02 - This duplicate of the previous sample showed thesame results.

SB-HTB-35-01 - The samples were a rough match for MC but the EPAsample contained acetone and total 1,2-dichloroethene at levelsthat are three times greater than the PCR samples.

SS-BA1-01 - This sample contained MC only in the PCR sample.However copper and lead were higher in the EPA split.

SS-C2B-01+02 - PCR showed hits of MC and acetone which were notdetected by EPA. The metals for both samples were identical.

SS-C3B-01 - No organics were detected in either and the metals wereidentical except for chromium and lead,which were both higher forPCR.

SS-B4B-01 - PCR showed hits of MC and acetone which were notdetected by EPA. Barium, chromium,copper, lead, and zinc were atleast twice as concentrated in the PCR sample.

SS-B5B-01 - Nothing was detected for organics, and the metal levelswere comparable.

Ground Water Samples

MW-2AS-01 - Organics were identical. Dissolved metals showedsimilar barium levels for both sets, but the EPA sample had higherchromium. Mercury and lead were detected by PCR but not by EPA.

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MW-3BL-01 - The levels of organics were identical in both samplesexcept for higher acetone in the EPA sample. The metal analyticalresults showed identical barium, lower chromium, and hits ofmercury and lead only in the PCR samples.

MW-16BF-01 - Organics were identical except that 1,1-dichloroethenewas found and trichloroethene was detected higher in the EPA sample(by over 100 ppb) . The metals were identical in both samples,except that PCR detected mercury.

Unfiltered Metals Samples

The following section describes the unfiltered (total) metalssamples obtained by Dynamac. As expected, the shallower wells,probably containing more silt, showed a greater discrepancy betweenthe filtered and unfiltered metals water sample analytical results.

HR-MW-2AS-01 Metals were between eight and ten times higher fornon-filtered replicates than for the PCR samples.

HR-MW-3BL-01 The metals were very close to the filtered samples inconcentration, especially between filtered and unfiltered EPA.

HR-MW-16BF-01 Metals were three times higher for barium andchromium, and lead was detected in the filtered sample.

Quality Control Samples

^cetone and chloroform were detected in an equipment blank, a fieldjblank, and in a trip blank that were associated with the wellsamples. Minute amounts of MC were detected in two trip blanks.

Some metals were detected in the rinsate blank associated with themonitoring well sampling. Because the equipment blank metals (forMCDE-13 and MCDE-12) are close to the field blank (MCDE-05)concentrations, these metals can be attributed to contaminantsalready within the rinsate water or absorbed from the atmosphericIdust at the site.

Other comments related to the Hunterstown Phase II RI Report, July,1991.

1. Page 1-9, para. 2: Were the excavations of the two DrumBurial Areas "lined"?

2. Page 2-8, para. 4: The year of drilling is indicated as 1991.Is this correct, or should it be 1990?

3. Page 3-7, para. 5: What is the source for an interpretationof "transverse faults"?

4. Page 3-15, para. 3: This paragraph raises once again the issue

5

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of the relatively low heads found at depthin the region of the lagoon plume. Why,in the view of PCR, was this data findingso important that a magnetometer surveywas performed? What does PCR view as thepotential implications of this data forremedial actions and the direction of deepground water flow?

5. Page 3-15, para. 4: Can PCR either characterize theuncertainty associated with theinterpretation of a west-northwest deepground water flow direction, or can theyshow how such a direction is consistentwith the head data for the deep wells inthe region of the lagoon in comparisonwith the stage elevations of Rock Creekand the N15E trends of on-site fracturetraces and the drainage that crosses thesite?

6. Page 4-13, para. 2: The last major clause of this sentence hasthree modifiers indicating uncertainty,"appears ... appear ... more-or-less".What is the significance of thischaracter i z at ion?

7. Page 4-22, para. 3: I note that the analysis of the three grabwater samples from the Stressed VegetationArea showed the highest concentrations ofCOI TALs of all water samples taken inPhase I or II, in fact several orders ofmagnitude higher. Does PCR view thesehigh levels found in-situ to besignificant with respect to the TCLPfindings?

8. Page 4-30, para. 1: With regard to the speculation that"volatiles would have volatilized prior tobackfilling which took place one yearlater", is it also possible that volatileswere also transported through the vadosezone to the ground water system byinfiltrating rainwater during this period?

9. Page 4-31, para, l: The surface drainage below the confluenceof Middle and West Streams is identifiedas Middle Stream. This identification isinconsistent with the identification onFigure 2-8, which shows the surface waterand sediment sampling locations.

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10. Page 4-31, para. 3: Where is the location of the backgroundwater sample (REF-1)? Was it from themajor tributary system to Rock Creeknortheast of the site? Why not map it fordocumentation purposes?

11. Page 4-39, section 4.2.4: Where is the location of theSanders' Septic Drainage? Is there a mapshowing its location?

12. Page 4-54, para. 2: "HMW-14S" should read HMW-14AS. Is thecharacterization of BEHP in ground watersamples as a laboratory contaminantsupported by more than generality, giventhat it was found in Borrow Area soilsamples and was not analyzed for in thesoil samples of other areas?

13. Page 5-3, para. 6: In discussing the ultimate fate of VOCs inground water, the last sentence stipulatesthat site VOCs "will discharge to RockCreek." Has PCR determined a region ofRock Creek over which these VOCs willdischarge to the stream? Are there anyintervening wells that might interceptthis natural flow of the VOCs to RockCreek?

14. Page 5-3, para. 6: This paragraph notes that "in the deepflow system" . . . ground water will flow... "west to northwest". Thisinterpretation is inconsistent with thatof page 3-15, paragraph 4, whichstipulates a west-northwest direction fordeep ground water flow. Is this acharacterization of the uncertaintyremaining after the RI process of the deepground water flow direction?

15. Appendix A, Logs: The following monitoring wells haveincorrect northings and eastings: 13-AE,13-BL, 14-AE, 14-BS, 18-CL (northing). Inaddition, there is a discrepancy betweenthe northing and easting coordinatesbetween HTB-3 and HMW-8BF in the Phase IIReport. Was HTB-3 the exact site of HMW-8BF, and if so, why are the reportedcoordinates different in the Phase II RIreport?

16. Table 3-1: The piezometric reading for HMW-12BE on11/12/90 is 405.14 feet (MSL), which is

AR306280

LJLj p^ ""S-consistent with the data sheet showing ameasurement of 137 feet below the casing,but which is inconsistent with two waterlevels taken on later dates. Should notthis reading be marked as a non-staticwater level, as it indicates significantpumping influence — unless PCR hasanother explanation for the 100 footdifference in the three water levelreadings? In addition, and moreimportantly, does PCR have anyinterpretation of the sink that wasoperating to cause this magnitude ofdrawdown in an area that is supposedlyserved by a public water supply system?

17. Figures 1-3, 2-11: It would be extremely helpful to reviewersand the public if PCR would identify thewells of Figure 1-3 and the well owners ofFigure 2-11 by their lot number, andindicate same in the map legends.

18. Figure 1-3: The distribution of roads southeast ofShealers Road and Business 15 is differentfrom that of Figure 1 of the May 28, 1991,Addendum to the Sampling and AnalysisPlan. Which is an accuraterepresentation? Members of the public maybe confused by this discrepancy.

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Antimony in Hunterstown Road Split Samples

The split samples taken during the phase II investigation ofthe Hunterstown Road Site were compared to the results obtainedby Paul C. Rizzo/Lancaster Labs. The split samples showedantimony levels of about 20 ppb while the PCR samples did notdetect antimony in the phase I sampling. The practicalquantitation limit however was higher than this level (30ppb).Antimony was present in surface wastes at the site and an MCL of3 ppb has recently been proposed. A discussion of backgroundlevels for antimony in groundwater was included in the FederalRegister proposal. The background information was contradictory:

1) One study of 39 utilities showed antimony ranges from 2-lOOppb.

2) A second study of 3,834 households (TAP) gave a range ofantimony of .6-4.0 ppb.

3) A study of 194 public utilities gave a range forantimony of 1-100 ppb with a mean of 25 ppb.

Background levels for antimony in groundwater appear to bepoorly defined and MCLGs may have been proposed that are abovetypical levels.

Additionally, Mr. Bhupi Khona indicated that other metalscan cause false positives in antimony analysis when antimony isat low levels.

DYNAMAC checked with the lab performing the split sampleanalysis. A lab blank gave a false positive and the lab was notconfident about the antimony numbers reported.

SR3G629I