LETTER FROM CRAIG BRANCHFIELD, SOLUTIA TO PAMELA …

S O L U T I A

July 16, 2004

Ms. Pamela!. Langston ScullyRemedial Project ManagerUnited States Environmental Protection AgencyAtlanta Federal Center61 Forsyth Street, S.W.Atlanta, GA 30303-3104

Solutia Inc.

575 Maryville Centre Drive

St. Louis, Missouri 63141

P.O. Box 66760

St. Louis, Missouri 63166-6760

Tel: 314-674-1000

Re: Anniston PCB SiteResponse to USEPA Comments on the RI/FS Work Plan, OU-3 Field Sampling Plan andOU-4 Field Sampling Plan

Dear Ms. Scully:

On behalf of Solutia Inc. and Pharmacia Corporation as parties to the Partial Consent Decree(CD) of the Anniston PCB Site, enclosed please find six hard copies and ten electronic copies ofthe Response to Comments on the Remedial Investigation/Feasibility Study (RI/FS) Work Plan,Operable Unit Three Field Sampling Plan (OU-3 FSP) and Operable Unit Four Field SamplingPlan (OU-4 FSP). These documents have been submitted in response to comments from EPAdated June 15, 2004, and received by the Parties on June 16, 2004, and in accordance with the CDincluding Section IX to the Agreement for Remedial Investigation/Feasibility Study (Appendix Ato the CD) and the Statement of Work, Appendix B to the CD.

Per my request to you in a letter dated July 16, 2004, revisions of the referenced documentsreflecting the enclosed responses will be provided to EPA no later than August 3, 2004.

Should you have any questions regarding this matter, please contact me at (256) 231-8404.

Sincerely,

Craig R. BranchfieldManager, Remedial Projects

CRB/jllEnclosures

cc: Mr. Phillip Davis (ADEM)Mr. G. Douglas Jones, Esq.Mr. Thomas Dahl

Response to USEPA Commentson the RI/FS Work Plan,

OU-3 Field Sampling Plan andOU-4 Field Sampling Plan

Anniston PCB SiteAnniston, Alabama

July 2004

BBE,BIASLAND, BOUCK & LEE, INC.engineers & s c i e n t i s t s

Responses to USEPA Comments on theRI/FS Work Plan, OU-3 FSP and OU-4 FSP

Anniston PCB SiteUSEPA ID No. ALD000400123 and ALD004019048

General Comments on RI/FS Work Plan:

COMMENT 1:

In general, there is a need to more clearly define the study area and distinguish it from the Site.The 100-year flood plain does not fully describe the Site. There are locations outside the 100-year flood plain where contaminants from the Site may have become located, through airdispersion or contaminated fill. (Example Section 4.6.3.1.1) Data collected in the study areaduring the Rl should indicate whether future investigations are warranted within the Site.

Response 1:

The Parties agree that data should be the basis for defining the Site. However, the definition ofthe Site in the Partial Consent Decree (CD) is sufficiently broad that the term "study area" is notnecessary. The CD states:

Site shall mean, for the purposes of this Consent Decree, the Anniston PCB Site,which consists of the area where hazardous substances, including PCBsassociated with releases or discharges as a result of the operations, includingwaste disposal, of the Anniston plant by Solutia Inc., Monsanto Company, andtheir predecessors have come to be located. The Site includes, but is not limitedto, the area covered by the RCRA Permit.

With regard to air dispersion as a potential transport mechanism, the soil and air data presented inthe Phase I Conceptual Site Model (CSM) Report for the Anniston PCB Site (BBL, 2003) do notsupport air dispersion as a transport mechanism. Rather, these data support surface water runoffand the placement of fill materials as the primary transport mechanisms. Figure 3-41 from thePhase 1 CSM Report presents the spatial extent of polychlorinated biphenyls (PCBs) in theChbccolocco Creek floodplain soils and confirms that PCBs transported via surface water areconfined to the 100-year floodplain. While PCBs are found outside of the 100-year floodplain ofSnow Creek, the sporadic nature of the PCB concentrations in these areas are consistent withplacement of fill materials, and not surface water transport or air dispersion. This includes thepresence of PCB-con tain ing foundry fill inside and outside of the floodplain. Air data collectedfor the Site and presented in Section 3.1.4 and Table 3-4 of the Phase I CSM Report indicate thatambient PCB concentrations are similar to those found in other urban areas of the United States.Notwithstanding this, the Parties have historically conducted sampling outside the 100-yearfloodplain under the Administrative Order on Consent (AOC). Sampling outside of thefloodplain will be conducted as described in the Field Sampling Plan (FSP) for OU-2 (BBL,2004) and the Supplemental Sampling and Analysis Plan (SSAP)for Operable Unit 1 (OU-1). Asdescribed in the FSP for OU-2, the Parties will evaluate the need for and extent of additionalsampling outside the 100-year floodplain based on the results of the sampling conducted for OU-1.

00642622-Final I of 71 7/16/2004



COMMENT 2:

Need to recognize that sufficient data needs to be collected to determine the nature and extent ofcontamination, assess risk, and develop alternatives. Past actions resulting in control measuresmust still be evaluated in the context of this RI/FS to determine what remedies are necessary.

Response 2:

The Parties agree that additional data are needed to complete the RemedialInvestigation/Feasibility Study (RI/FS) for the Site and that the RI/FS will consider theprotectiveness of cleanup activities that have been conducted under the Resource Conservationand Recovery Act (RCRA) program as corrective measures. Data needed to complete the RI/FSare identified in the FSPs prepared for each OU and were identified in accordance with UnitedStates Environmental Protection Agency (USEPA) USEPA Guidance for Conducting RemedialInvestigations and Feasibility Studies Under CERCLA (USEPA, 1988), Guidance for the DataQuality Objective Process (USEPA, 1994a) and requirements stipulated in the Statement of Workcontained in the CD. Supplemental sampling plans will also be developed as additional dataneeds are identified throughout the RI/FS process for this Site.

Specific Comments on RI/FS Work Plan:

COMMENTS:

Section L4,pagel-3

Conceptual Site Model was approved with comments. One comment described the need toconsider combining OU1 and OU2. Please describe how this comment was considered so thatsome closure can be given to the issue. Also, need to revise statement that primary sources havebeen addressed. This investigation will determine whether or not primary sources have beenadequately addressed.

Response 3:

The Parties agree that OU-1 and OU-2 can be combined. Combining the two OUs will maximizethe use of data collected under the non-time critical (NTC) Removal Action Agreement and willstreamline the RI/FS process in terms of the number of deliverables that need to be developed.To minimize any confusion between the Phase I CSM Report that identifies a total of four OUs,the term OU-l/OU-2 will be carried forward for use in the RI/FS Work Plan and subsequentdocuments to describe the areas of the Anniston PCB Site north of Highway 78 up to andsurrounding the plant site. The only exception to the southern boundary of the OU-l/OU-2 areais the Oxford Lakes Neighborhood (OLN) area as defined in the Removal Order. The lateralbounds of the OU-l/OU-2 area will be defined through data collected during RI/FS process. Theinitial lateral bounds for sampling in the OU-l/OU-2 area are the 100-year fioodplain and theadditional areas identified in the FSP for OU-2 and the SSAP for OU-1. Once data are availablefor this initial area, the need for and extent of additional samples will be evaluated and aSupplemental FSP will be developed if additional data are needed.

00642622-Final 2 of 71 7/16/2004



COMMENT 4:

Section 1.4.1, page 1-3

This section should describe the RI/FS process which will be conducted to ensure that actionstaken through the NTC removal are protective of human health and the environment. NTCRemoval Action only considered the soil exposure pathway, which is considered the most criticalpathway. The RI/FS will consider all exposure pathways.

Response 4:

The Parties agree that the RI/FS for the Site will consider all applicable exposure pathways.However, this section of the RI/FS Work Plan describes the geography of the areas that had beenproposed for OU-1 and not exposure pathways to be considered in the RI/FS process.

COMMENTS:

Section 1.4.4, page 1-4 and Section 2.1, page 2-2

Provide some justification why the investigation should be limited to Choccolocco Creek. Thereis considerable concern that Lake Logan Martin and Lay Lake have experienced impacts thathave not been investigated.

Response 5:

As noted in Section 3.4.2.4 the Phase ICSM, PCB concentrations are not detected in the surfacesediments of Lake Logan Martin. In addition, PCB concentrations in fish tissue continue todecline and are on average below the state of Alabama consumption guideline of 2 milligrams perkilogram (mg/kg). In addition, there are upstream sources of PCBs to and in the lake that resultin background PCB concentrations. -»

/ «(\jo~VCOMMENT 6: C~"V1==-

Section 2, pages 2-1, 2-14, 2-16 and 2-17

Text refers to prior remedial actions. Prior actions were probably corrective measures underRCRA program. They should not be referred to as remedial actions in order to reduce confusionabout program implementation in future years.

Response 6:

The text of the revised RI/FS Work Plan will be modified to refer to prior remedial actions ascorrective measures under RCRA, as requested. In addition, the following two quotations fromthe RCRA Corrective Action Plan (USEPA, 1994b) will be incorporated in to Section 2 of therevised document in order to introduce the Corrective Action Program and to clarify the scope ofcorrective measures:

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The objective of a Corrective Action Program at a hazardous waste managementfacility is to evaluate the nature and extent of the releases of hazardous waste orconstituents; to evaluate facility characteristics; and to identify, develop, andimplement an appropriate corrective measure or measures to protect humanhealth and environment.

In addition,

The four main components of a complete corrective action program and theirobjectives are as follows:

• Interim/Stabilization Measures (ISMs) - to control or abate threats to humanhealth and/or the environment from releases and/or to prevent or minimize thefurther spread of contamination while longterm remedies are pursued.• RCRA Facility Investigation (RFI) - to evaluate thoroughly the nature andextent of the releases of hazardous waste and hazardous constituents and togather necessary data to support the Corrective Measures Study and/orinterim/stabilization measures.• Corrective Measures Study (CMS) - to develop and evaluate a correctivemeasure alternative or alternatives and to recommend the final correctivemeasure(s).• Corrective Measures Implementation (CMI) - to design, construct, operatemaintain and monitor the performance of the corrective measure(s) selected.

COMMENT 7:


Are the prevailing winds from east-northeast or to east- northeast? Can the recent air studymeteorological data be used to supplement what is know about wind directions near the site. Ifnot yet, study should be mentioned.

Response 7:

The revised'RI/FS Work Plan will be modified to reflect the meteorological data presented in theENSR air report submitted in July of 2004. Meteorological data collected by the USEPA andpresented in Anniston PCB Air Sampling Report (ATSDR, 2003), indicate that the prevailingwind direction is to the east-northeast 30% of the year and to the west-southwest approximately15% of the year. These data were reported for the USEPA's two sampling periods (i.e., June 27-28 and June 29-30). For those sampling periods wind direction was from the southwest 79-87%of the time, with calm winds occurring in the evening and overnight hours.

COMMENTS:


The text notes that there are over 150 springs identified and located in the County. The textshould note the location and distance from the site of the closest spring(s).

00642622-Final 4 of 71 7/16/2004I

Responses to USE PA Comments on theRI/FS Work Plan, OU-3 FSP and OU-4 FSP


Response 8:

The revised RI/FS Work Plan will be modified by adding the following sentence to Section 2.2.2just before the sentence that begins "Coldwater Spring, located ...":

"The two most significant springs located nearest to the Facility are Collateral Spring andColdwater Spring with both springs located approximately five miles from the Facility.Collateral Spring is located to the south of the Facility near Interstate 20."

tCOMMENT 9:

Section 2.23i

The significance of a possible zone of relatively higher hydraulic conductivity in the "transitionzone ", or weathered bedrock (stratigraphically on top of the competent bedrock) is not discussed.This zone may be an important pathway for groundwater movement.

Response 9:

As mentioned in Section 2.2.3, the Facility consists of two primary stratigraphic units; theresiduum and the bedrock. The transition zone moves from one to the other as a gradual change.Other than descriptive information concerning its presence as weathered bedrock in the boringsthat penetrated the unit, no specific hydrogeologic information is available. Consequently, anydiscussion concerning hydraulic conductivity would be considered speculative. Also, while it ispossible to think of this unit as an important pathway for groundwater movement, it is equallyimportant to remember that residuum is weathered bedrock.

IThe significant issue is whether this transition zone is an important pathway for groundwatermovement. Solutia would consider this zone as a potential important pathway if there wasevidence suggesting deep migration of contaminants at the facility. This was an issue that wasaddressed as part of the RCRA investigations at the facility.

For the RCRA investigations at the facility, seven deep residuum wells were installed (WellsOWR-1D through OWR-7D). The results from the sampling of these seven wells are as follow:

OWR-1D - no parameters reported above permit limits or MCLs;OWR-2D - no parameters reported above permit limits or MCLs;OWR-3D - dry well (no sample collected);OWR-4D - no parameters reported above permit limits or MCLs;OWR-5D - chlorobenzene (46 ug/L) above permit limit (1 ug/L) but below

' MCL( 100 ug/L),pentachlorophenol (1.2 ug/L) above permit limit (1 ug/L),

: 4-nitrophenol (2,300 ug/L) above permit limit (1,000 ug/L),i methyl parathion (5.5 ug/L) above permit limit (MDL),, PCBs (210 ug/L) above permit limit (0.5 ug/L) (filtered BDL),' Cobalt (0.081 mg/L) above permit limit (0.01 mg/L),I Lead (0.021 mg/L) above permit limit (0.015 mg/L);

00642622-Final 5 of 71 7/16/2004

j Responses to USE PA Comments on thei RI/FS Work Plan, OU-3 FSP and OU-4 FSPJ Anniston PCB SiteI USEPA ID No. ALD000400123 and ALD004019048i

OWR-6D - no parameters reported above permit limits or MCLs; andOWR-7D - PCBs (2.2 ug/L) above permit limit (0.5 jig/L) (filtered BDL)

These results generally confirm that the deeper zone within the residuum is not impacted withcontaminants. However, as noted above there were two areas where impacts were noted: WellOWR-5D and Well OWR-7D. Well OWR-5D is located within the recovery well system at theSouth Landfill at a depth of 65 ft bgs. Interceptor wells were completed to depths of 68 ft bgs inthe immediate vicinity of Well OWR-5D. Therefore, detections in Well OWR-5D should beexpected since the well is located in close proximity to inceptor wells that actively pumpcontamination towards this location.

Well OWR-7D is located in the vicinity of the West End Landfill and has been part of a WestEnd Landfill monitoring program. The West End Landfill monitoring program consists of foursuccessive semi-annual sampling events prior to recommending a final monitoring program forthis area of the Facility. This monitoring program has recently been completed. Theconcentration of PCBs in Well OWR-7D consistently decreased from a high of 2.2 ug/1 in 1998(RFI sampling) to 1.81 ug/1, to 1.5 (J) ug/1, to 0.61 ug/1, to non-detect in the sampling events forthe West End landfill sampling program. Based on the trend of decreasing to non-detect data,drag down ;of contamination during well installation was considered the likely cause of thedetections in the deep residuum zone.

iResults from none of the other deep residuum wells indicated any contamination in the deepresiduum zone. This is significant, particularly since the wells were placed in areas where deepercontamination might be expected. Well OWR-4D was placed down gradient of the OLBSIrecovery system in the vicinity of Well OW-21 and Well OW-22. Impacts were reported in thesetwo shallow monitoring wells but not in Well OWR-4D. Well OWR-2D was placed in thevicinity of a bedrock trough, a potential area of preferential flow. Again, the results from WellOWR-2D indicate contaminants are not present in the deep residuum zone. Wells OWR-1D andOWR-6D were installed in the northeast area of the site, and both wells were free ofcontamination. Well OWR-3D was placed in an area in the interior of the Facility and was foundto be dry, indicating the presence of neither contaminants nor groundwater in this area of theFacility. j

As a result, it is apparent that contamination at the Facility does not extend to the deep residuum.Given the low permeability nature of the residuum, this is true from a hydrogeologic standpoint(groundwater flow is restricted) and from a contaminant location standpoint (existing deepresiduum wells do not indicate the presence of contaminants at depth). Because of the lack ofcontamination in the deeper residuum wells, the transition zone is not considered to be animportant pathway for groundwater transport.

iCOMMENT 10:

Section 2.214.3

Please provide more information about the NRCS work and how it will relate to the RI/FS. Willadditional work be required to locate and describe the piles?

00642622-Finai 6o f71 7/16/2004



Response 10:

The text of ;the RI/FS Work Plan will be updated to reflect that detailed information includingdescriptions', measurements and photographs of the spoil piles are provided in a report titledDredge Spoil Area Evaluation Report, Snow Creek and Choccolocco Creek, Calhoun andTalladega Counties, Alabama (Roux Associates, Inc. 1998). Based on the findings on this report,no additional data are needed to characterize these soil piles. With regards to the FS portion ofthe comment, interim measures were also proposed to stabilize these piles, but were neverapproved/implemented by the Alabama Department of Environmental Management (ADEM). Afigure showing the locations of these piles will be included in the revised RI/FS Work Plan. Thepiles will be considered during the RI/FS process.

i

COMMENT 11:

Section 2.2:5, page 2-13

Are there any tribal grounds, historic sites, or artifacts that need to be considered prior toworking in, the impacted areas? This section should include ecologically and economicallyimportant natural resources. At least 12 Federally listed endangered species occur in areaspotentially affected by COPC from the Facility. Recreational and commercial fisheries andshellfisheries should be identified in impacted areas.

\

Response 11:

The text of the RI/FS Work Plan will be updated to reflect that an evaluation of cultural andnatural resources, as well as recreational and commercial fisheries will be considered as part ofthe data quality objective (DQO) development process including Steps 3 and 4 of the ecologicalrisk assessment for Choccolocco Creek and its floodplain. Similarly, in the event that the resultsof the SLERA for OU-1/2 and OU-3 indicate further evaluation is needed, the evaluation ofcultural and natural resources will be considered. Regarding the potential for listed endangeredspecies to inhabit OU-1/2, the approach employed in the SLERA is adequate to address thisconcern. [The ecological screening values used in the "Toxicity Evaluation" and "RiskCalculation" are conservative in nature and represent threshold levels protective of individualorganisms;; thus they are sufficiently protective for this step in the assessment. A more detailedevaluation of these species will be developed in subsequent steps of the Baseline Ecological RiskAssessment if it is determined at the Science/Management Decision Point that additional work isrequired. '•

The RI/FS Work Plan will also be revised to reflect that planning for field investigations willinclude an evaluation of the potential presence of cultural and natural resources and that theRI/FS process for each OU will consider the potential presence of tribal grounds, historic sites,ecologically or economically important resources including potential recreational and commercialfisheries arid shell fisheries.

00642622-Final 7 of 71 7/16/2004



COMMENT 12:

Section 2.3.2.3, page 2-17i

Provide reference for location of storm water and non-storm water data. Didn 't Solutia recentlyrequest to decommission the facility's wastewater treatment facility? Are there data records forthe facility 'siwastewater treatment facility in any existing reports?

Response 12:i

As part of the on-Site RCRA Feasibility Investigation/Confirmatory Sampling (RFI/CS)investigations, surface water runoff samples were collected from several outfalls near the Facilityand landfills. The outfalls sampled included DSN 004, DSN 005, DSN 006, and DSN 012. Theresults of these samples are included in the RFI/CS Report for the Anniston, Alabama Facility(Golder, 2002). In addition to the samples collected during the on-Site RFI/CS investigation,surface water samples are collected on a quarterly basis in accordance with the National PollutantDischarge Elimination System (NPDES) permit for the Facility. Analytical sampling data fromthe On-Facility program, as well as the NPDES permit monitoring program have been providedin Appendix C of the Phase I CSM Report. It should be noted that the analytical data for eachoutfall varies due to changes in the ways the Facility addressed stormwater and changes to theFacility's NPDES permit over time.

The following language will be added after the second sentence of the first paragraph in Section2.3.2.3 of the revised RI/FS Work Plan:

"Analytical sampling data for these stormwater outfalls is presented in Appendix C of the Phase ICSM Report (BBL, 2003)."

i

With regard to the USEPA's question about decommissioning the Facility's wastewater treatmentfacility, Solutia did request a modification to their RCRA Part B Permit from the ADEM todecommission the facility. Solutia recently discontinued the manufacture of paranitrophenol(PNP) and will no longer require on-Site biological treatment. As a result, the biologicalwastewater treatment facility was decommissioned and modified to serve as an equalization basinand to facilitate pH control for the remaining plant waste streams.

The third and fourth sentence of the first paragraph of Section 2.3.2.3 of the revised RI/FS WorkPlan will be modified as follows:

"A single n'on-stormwater-discharge point from the Facility discharges to the City of Anniston'sPublicly Owned Treatment Works (POTW). All process-related water from the Facility and allgroundwater recovered through the on-Facility groundwater extraction systems are dischargedthrough this outfall."

With regard to the USEPA's question about data records for the Facility's wastewater treatmentfacility data records have not been submittd in any reports. However, while the Facility'swastewater! treatment plant was in service, Solutia submits discharge monitoring reports (DMRs)on a monthly basis to ADEM and the Anniston Water and Sewer Board.

00642622-Fina 8 o f 7 l 7/16/2004

{ Responses to USEPA Comments on theRI/FS Work Plan, OU-3 FSP and OU-4 FSP

I Anniston PCB Sitei USEPA ID No. ALD000400123 and ALD004019048I

COMMENT 13:\

Section 2.3.3. 1, page 2-18\

Provide reference for location of former drainage ditches with impacted sediments.tt

Response 13:I

The locations of the former drainage ditches referred to in Section 2.3.3.1 are included in theDetailed Design Report for the West End Landfill Cover Revisions (Colder, 1995) and the FinalReport for the Detention, Cap, and Cover Project at the Solutia Anniston Facility (ICF KaiserEngineers, 1998).

These references will be added to the revised document.

COMMENT 14:i

Section 2.313.2, page 2-19i

For SWMU41 and SWMU42, which cell in landfill was material described placed in. Provide anaccounting 'of movement of contaminated materials in all operable units. \

Response 14:

Demolition^ materials including excavated impacted soils from both SWMU 41 and SWMU 42were placed in Cell 5E of the South Landfill.

The Anniston PCB Site is an extremely large site, which encompasses approximately 70 acres onthe plant site alone. The Site also includes hundreds of acres surrounding the plant site, industrialand residential properties within the cities of Anniston and Oxford, and waterways from the 1 1 lh

Street Ditch to Snow Creek to Choccolocco Creek. An accounting of the movement ofcontaminated materials at the Site has been included in numerous reports submitted to theUSEPA and ADEM. Additionally, much of the work is on-going and future reports will besubmitted to document the remedial actions. Reports that provide the requested informationinclude: '

iAlabama Department of Environmental Protection (ADEM). 2001. Hazardous Waste FacilityPermit. RCRA Post-Closure Permit for WMA I (Closed Hazardous Waste Landfill Cells) andWMA II (Closed Surface Impoundment). Solutia Inc. ALD 004 019 048. Issued January 7, 1997.Modified November 13, 1997 and May 3, 2001 .

A.T. Kearney, Inc., 1991. "RCRA Facility Assessment," August 1991.

Blasland, Bouck & Lee, Inc. (BBL). 1999. Supplemental RCRA Facility Investigation Work Planfor the Off-Site Portion of the RFI/CS Program, February 1 999.

BBL. 2000. Off-Site RCRA Facility Investigation (RFI) Report, June 2000.i

BBL. 2000. Phase II Off-Site (Floodplain) RFI/CS Investigation Work Plan, April 2000.iiI

00642622-Final 9 of 7 1 7/16/2004



Colder Associates Inc. (Colder). 1998. RFI/CS Work Plan for the Anniston, Alabama Facility,1998.

Colder. 1999. On-Site RFI/CS Draft Report for the Anniston, Alabama Facility, January 1999.

Colder. 2002. RFI/CS Report for the Anniston, Alabama Facility, October 2002.

Colder. 2002. Supplemental RFI/CS Work Plan for Solutia Inc., Anniston Facility, August 2002.

Colder. 2002. Revised Interim Measures Plan for Solutia Inc., September 2002.

ICF Kaiser Engineers, Inc. 1998. Final Report for the Detention, Cap, and Cover Project theSolutia Anniston Facility, June 5, 1998.

Monsanto Company. 1996. Correspondence to USEPA Providing Comments to RFA, February 1,1996.

Monsanto Company. 1996. RCRA Part B Post-Closure Permit Application for Anniston,Alabama, April 1996.

Roux. 1999. Dredge Spoil Area RFI/CS Phase I Report, Snow and Choccolocco Creeks, Calhounand Talladega Counties, Alabama, September 13, 1999.

Roux. 2001. Removal Response Action Work Plan, llth Street Ditch, Anniston PCB Site,Anniston, Alabama, July 9, 2001.

Roux. 2002. RCRA Facility Investigation Results and Interim Measures Plan, Oxford LakeSoftball Complex, West Area, February 6, 2002.

Roux. 2002. Northside Cover Extension Interim Measures Report, Solutia Inc. Facility, AnnistonAlabama, July 8, 2002

Roux. 2002. Parking Lot Multi-Layer Cover Interim measures Report, Oxford Lake SoftballComplex, Anniston, Alabama, September 18, 2002

Roux. 2002. MMC Warehouse Interim Measures Report, Solutia Inc. Facility, Anniston,Alabama, September 6, 2002

Roux. 2003. Tennis Court and Parking Area Interim Measures Report, Oxford Lake SoftballComplex, Anniston, Alabama, May 28, 2003

Roux. 2004. Northside Cover Extension Interim Measures Report, Solutia Inc. Facility, AnnistonAlabama, April 21, 2004

Roux. 2004. Oxford Lake Softball Complex Interim Measures Report, Solutia Inc. Facility,Anniston, Alabama, May 25, 2004

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Solutia. 2000. Interim Measures Work Plan for Extension of North Side Cover, Solutia Inc.Facility, Anniston, Alabama, January 24, 2000.

Solutia. 2000. Off-Site QML Soil Characterization and Remediation Plan, July 27, 2000.

Solutia. 2000. Corrective Measures Implementation Plan for Highway 21 Bridge, Revision 1,June 29, 200

Solutia. 2001. Interim Measures Work Plan, MCC Warehouse, Solutia Anniston Facility, May 17,2001.

Solutia. 2001. Quintard Mall Expansion Supplemental Off-Site Soil Report, November 2, 2001.

Solutia. 2001. Removal Action Work Plan for the Stockpiled Soil at the Oxford Lake SoftballComplex, April 24, 2001.

Solutia. 2002. Correspondence to USEPA titled Design and Implementation Schedule for llthStreet Ditch Response Action, Anniston PCB Site, Anniston, Alabama, April 15, 2002.

Solutia. 2002. Corrective Measures Study for Excavated Soil Stockpile at Choccolocco CreekWaste Water Treatment Plant, Oxford, Alabama, February 22, 2002.

Solutia. 2003. NTC Removal Action Engineering Evaluation and Cost Analysis (EE/CA) Reportfor the Anniston PCB Site, Rev. 1.0, Anniston Alabama.

Solutia. 2003. Corrective Measures Implementation Work Plan for Excavated Soil Stockpile atChoccolocco Creek Wastewater Treatment Plant, Anniston, Alabama. January 2003.

URS Corporation. 2001. Soil Sampling Work Plan, The Anniston Wastewater Treatment Plant,April 2001.

URS Corporation. 2001. Interim Measures Plan, Anniston Water Works and Sewer Board,Choccolocco Creek WWTP Additions and Improvements, Oxford, Alabama, October 2001.

COMMENT IS:

Section 2.3.3.2, page 2-20

Provide reference for NPDES data from storm water sewer.

Response 15:

As discussed in Response No. 12 analytical sampling data from the NPDES permit monitoringprogram have been provided in Appendix C of the Phase I CSM Report. Additionally, the dataare provided to ADEM on a quarterly basis. The following language will be added at the end ofthe last paragraph in Section 2.3.3.2 of the revised RI/FS Work Plan:

00642622-Final ] I of 71 7/16/2004



"The analytical sampling data are reported to ADEM on a quarterly basis and are summarized inAppendix C of the Phase ICSM Report"

COMMENT 16:


The text states that PNP and parathion monitoring at WMA II Corrective Action system data for1989, 1996, 1999, and 2003 are shown on Figures 2-15 and 2-16. In fact, only data from 1989,1996, and 2000 are shown. Contrary to what the last sentence of this section indicates, there issignificant evidence suggesting that the groundwater corrective actions taken to date may nothave been successful in containing impacted groundwater. Are there more recent data? If so, itshould be added to the figure and/or the discussion.

Response 16:

Figures 2-13 through 2-16 of the revised RI/FS Work Plan will be updated by adding trend plotsfor some of the wells that have been recently sampled and, Section 2.3.3.3 will be updated asindicated below. Additional data for the SWMU 1 Corrective Action System will also be addedfor the WMA II Corrective Action System so that the description and presentation of data for thetwo corrective action systems are consistent.

The third paragraph under Section 2.3.3.3 of the revised RI/FS Work Plan will be modified asfollows:

"Results of PNP and parathion monitoring at the SWMU 1 Corrective Action System from 1989to the present indicate that the overall concentrations of PNP and parathion have decreased andare currently below regulatory limits in each of the sampled monitoring wells. Isopleth plots ofdata from 1989 and 1996 that are presented on Figures 2-13 and 2-14 illustrate the reduction inconcentrations. Trend analyses of analyte concentrations at individual interceptor wells andobservation wells used to monitor the performance of the SWMU 1 Corrective Action System arealso presented on Figures 2-13 and 2-14. These analyses, which include data from more recentsampling events, have generally shown decreasing PNP and parathion concentrations at each ofthe wells. For example, PNP concentrations in observation well OW-8A located downgradient ofthe interceptor well system have decreased from 0.0095 milligrams per liter (mg/L) in 1989 tonon-detectable levels since 1996. Parathion concentrations in OW-08A increased from non-detect in 1989 to 0.0013 mg/L in 1998; and have decreased since 1998 to non-detect in the mostrecent sampling event. Corresponding decreases in PNP and parathion concentrations are alsoevident at the interceptor wells.

The fifth paragraph under Section 2.3.3.3 of the revised RI/FS Work Plan will be replaced withthe following two paragraphs.

"Results of PNP and parathion monitoring at the WMA II Corrective Action System arepresented as isopleth plots of data from 1989 and 1996 on Figures 2-15 and 2-16. These plotsindicate that the overall extent and concentrations of parathion and PNP have decreased duringthe time frame. Trend analyses, which include data from more recent sampling events, are alsopresented on Figures 2-15 and 2-16. These plots confirm the trend of decreasing concentrations.

00642622-Final 12 of 71 7/16/2004



Analytical data collected semi-annually indicate that the WMA II Corrective Action System hasbeen effective, as measured by the large reductions in concentrations of PNP and parathion inobservation wells immediately downgradient of the pumping system. Monitoring well OW-19contained groundwater with PNP concentrations of 142 mg/L and concentrations of parathion of0.097 mg/L in 1989. The concentrations for each of these analytes have decreased over time andwere non-detect in the two most recent sampling events. Well OW-24 had concentrations of PNPdecrease from 0.392 mg/L in 1990 to below detection limits for the two most recent samplingevents, and parathion concentrations decreased from 0.882 mg/L to 0.290 mg/L during the sameperiod.

The analytical results for one well (OW-21 A) have not followed this same trend. At this location,both PNP and parathion concentrations have recently increased. A modification to the WMA IICorrective Action System implemented in 2003 is anticipated to aid in the reduction of thesecompounds in future sampling events. However, further investigations have been proposed toaddress recent detection of compounds found in OW-21A samples (see Section 3.5.3.3.1)."

COMMENT 17:


Where was material removed from the ditch disposed of? Please provide a table to account forall previous material removed showing how material was disposed.

Response 17:

Approximately 1,000 tons of sediment was excavated from the 11th Street Ditch and the first 100feet of Snow Creek, after the confluence with the 1 llh Street Ditch. The material was transportedand disposed at an off-Site landfill owned by Chemical Waste Management in Emelle, Alabama.Accounting of previous material removed at the Site is discussed in response to Comment No. 14

COMMENT 18: ""

Section 2.4, page 2-24, 2-25, and 2-26

Please remove conclusions about risk and effect of previous actions. The point to the RI/FS is tomake that determination. EPA acknowledges that significant work has been done to rectifypotential exposure. Conclusions about whether efforts are adequate should not be made in thiswork plan. Contrary to what the first bullet indicates, there is significant evidence suggesting thatgroundwater contamination is not being effectively controlled within the On-Facility area andthat it does present a potential risk to Off-Facility areas. There is some evidence thatcontamination may be moving off site to the north (increasing contaminant concentrations inOW21). Storm water may meet NPDES requirements, but may still be affecting ecologicalreceptors.

Response 18:

The Parties will qualify the conclusions in this section of the document for groundwater aspreliminary and state that additional data will be collected to further evaluate the concerns

00642622-Final I 3 o f 7 1 7/16/2004

Responses to US EPA Comments on theRI/FS Work Plan, OU-3 FSP and OU-4 FSP


identified in the comment relative to well OW-21. Similarly, stormwater data will continue to becollected to evaluate the effectiveness of corrective measures previously implemented at the plantsite. This evaluation will be conducted as a part of the RI/FS process for OU-3.

COMMENT 19:

Section 2.4, page 2-25

PCBs have been identified in past studies as the primary COPC. A sampling program designed toconfirm that will be implemented in the RI/FS. Use of contaminated fill was also identified in theCSM as a transport mechanism for PCBs at the Site. Conclusions about PCB's rarely beingdetected outside the 10-year flood plain may only be tnte in reference to a specific study.Generalizations should be put in context.

Response 19:

This section of the RI/FS Work Plan will be modified to reflect that Site-related constituents arerarely detected outside the footprint of the 10-year floodplain when surface water transport is thetransport mechanism. This conclusion is supported by the PCB soil data for the ChoccolocccoCreek floodplain presented Figure 3-41 of the Phase I CSM Report. While these data are for OU-4, they are also directly applicable to the transport of Site-related constituents in the Snow Creekfloodplain (i.e., the OU-l/OU-2 area). However, the distribution of Site-related constituentswithin and outside of the 10-year floodplain of the OU-l/OU-2 area also reflects the relocation offoundry fill and 100 plus years of industrial activity within the watershed.

COMMENT20:


According to the results presented in Figure 2-18 and in Table 2-1, there are several samples atSWMU-12 with higher PCB concentrations than the sample collected from SWMU-25. Why isthe SWMU-25 sample the only one considered to exceed SSTLs? Please explain.

Response 20:

The following language will be added to the first sentence of the third paragraph in Section2.5.1.1 of the revised RI/FS WorkPlan:

"Different site-specific target levels (SSTL) were developed based on exposure potential for theHealth and Environmental Assessment component of the RCRA Feasibility Investigation/Confirmatory Sampling (RFI/CS) Report (Colder, 2002b). For areas where there was potentialfor routine contact (i.e., areas of the plant associated with ongoing manufacturing activities), amore conservative SSTL (i.e., a lower concentration value) was developed and identified as thehigh contact SSTL. For areas of the Facility where exposures were limited (i.e., no activeproduction structures, storage areas, maintenance areas, or frequently traveled roads exist), a lessconservative SSTL was developed and identified as the low contact SSTL. A separate SSTL wasdeveloped for construction/utility workers who had a potential for exposure to subsurface soil

00642622-Final I4of71 7/16/2004



concentrations. The results of the soil samples were compared to the appropriate SSTLs. Basedon the comparison..."

COMMENT 21:


What were the total PCB concentrations for the samples analyzed for 10 PCDF congeners?What is the TEC for the concentrations? What is the significance of these sample locations?

Response 21:

One sample (SWMU 42-6A) along with a duplicate sample (SWMU -42-6B) was analyzed for 10polychlorinated dibenzofurans (PCDF) congeners during the supplemental RFI/CS investigation.The results of these analyses are presented in Table 2-2 of the RI/FS Work Plan. The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity equivalent (TEQ) calculated for the averagecongener concentrations (average of original and duplicate) is 0.24 micrograms per kilogram(ug/kg). The location of the sample was selected based on proximity to sample SSR-18, whichexhibited the highest concentration (13,400 J mg/kg) of PCBs measured on the Facility during theRFI/CS investigation.

COMMENT 22:

Section 2.5.1.2,page 2-30

Concerning observation well OWR-10, located down gradient of the West End Landfill, the textstates that: "Very low concentrations of PCBs were detected in the sample (concentration of 1.8ug/l). Subsequent sample results from this location have been non-detect for PCBs, indicating apotential laboratory problem associated with the detected result. " However, sampling results forthis well reported in the First 2003 Semi-Annual Groundwater Detection Monitoring andCorrective Action Effectiveness Report, indicate a detected concentration of 1.0 ug/l (above theDetection Limit). When were the samples from this well that reportedly were "non-detect" forPCBs collected? What data are there supporting that the detection of PCB in this well was due toa laboratory problem, as opposed to the non-detection being due to a laboratory problem?Contrary to what the last paragraph of this section indicates, there is significant evidenceindicating that impacted groundwater may be migrating offsitefrom these areas.

Response 22:

PCBs were detected at a concentration of 1.8 micrograms per liter (ug/L) during the initialsampling of OWR-10 which occurred as part of the Supplemental RFI/CS Investigation. Thewell was sampled again approximately one month later as part of the spring 2003 semi-annualgroundwater monitoring event, and PCBs were detected at a level of 1.0 J ug/L, flagged asestimated by the contract laboratory. Both of these results were from unfiltered samples. Filteredsample results from these two events were non-detect for PCBs. Samples collected during boththe fall 2003 and spring 2004 semi-annual groundwater monitoring events showed non-detect for

00642622-Final 15 of 71 7/16/2004



PCBs for both filtered and unfiltered samples'.Section 2.5.1.2 will be revised as follows.

The sixth sentence of the last paragraph in

"Subsequent sample results in the spring 2003, fall 2003, and spring 2004 semi-annualgroundwater monitoring events, indicated PCB concentrations of 1.0 J ug/L, flagged as estimatedby the contract laboratory, non detect and non-detect, respectively."

The suggestion that impacted groundwater may be migrating off-site is not supported byanalytical data for OWR-10, nor is it supported by data for other wells located downgradient ofthe West End Landfill (i.e.: WEL-1, WEL-2, WEL-3 and OWR-7D) presented in the table below.

Sampling Results for Wells at the West End Landfill

: Sampling Event

fall 2002spring 2003fall 2003spring 2004

WEL-1

0.69NDNDND

WEL-2

NDNDNDND

: WEL-3

1.00.521.72ND

OWR-7D

1.811.5J0.61ND

It should be noted that monitoring around the West End Landfill was conducted as a result ofcomments provided by USEPA in the Environmental Response Team "Final Summary Report ofTechnical Review and Evaluation of Potential PCB Releases" dated May 2001. The Partiescommented on the report that although groundwater monitoring data around the West EndLandfill indicate groundwater is not impacted, they agreed (consistent with agreements madewith ADEM) to conduct a two-year, semi-annual sampling program. Further, the Parties agreedto install and sample an additional monitoring well - OWR-10. This semi-annual samplingprogram has now been completed, and as the above data indicate, groundwater impacts are notpresent around the West End Landfill.

COMMENT 23':


Better habitat assessments are needed.

Response 23:

Section 2.5.4 provides only a summary of the SLERA that are provided in Appendices E and F,and therefore, a detailed descriptions of habitat assessments for OU-1, 2, and 3 were not includedin this section. However, a referring sentence will be added to Section 2.5.4 directing the readerto appropriate sections of Appendices E and F. Also, additional work, in the form of speciessurveys, is planned to fill a data gap identified in the SLERAs. These additional activities willsupplement the habitat assessments contained in the SLERAs.

A copy of the analytical data from the Spring 2004 sampling is included as Attachment A.

00642622-Final I6of71 7/16/2004



COMMENT 24:


EPA agrees that OU1 And OU2 can be combined for the Screening Level (SLERA), however EPAdoes not agree that habitat quality and limitations for residential areas is the same ascommercial areas. Commercial areas covered in paving and buildings is very different habitat.It is recommended that the species survey be conducted on both OUs.

Response 24:

Given the contiguous nature of OU-1 and OU-2, and that these areas share many physical (jfl*similarities; adequate information on urban species can be obtained by surveying the morereadily-accessible properties in OU-2. Survey locations will be positioned so as to obtaininformation form both OUs in those areas where regions of OU-2 are in close proximity to OU-1.Thus, a species survey for OU-2 should reasonably approximate the species distribution at OU-1.

COMMENT 2 5:


Reference to RI data at the end of the first paragraph needs to be corrected. The RIfor OU1 andOU2 does not exist yet. Second paragraph needs to be completely rephrased. Don't make strongjudgements about habitat quality prior to conducting species surveys described at the end of theparagraph. It is not sufficient to imply that the habitat for OU2 will be the same as the habitatfor OUI. The surveys may be conducted in the FSP for OU2, but should cover the habitat forboth OUI and OU2.

Response 25:

The text referring to the RI will be modified by removing any reference to the RI for OU-l/OU-2area.

The second paragraph will be modified to read as: "Limited areas of attractive habitat within OU-1 and OU-2 identified in the habitat surveys reduce the probability that ecological receptors willreside in these areas and be exposed to the identified COPCs. Supplemental data in the form ofspecies surveys will be conducted to reduce the uncertainty associated with the limitationsinherent in the habitat surveys."

COMMENT 26:


What OU3 remediation activities were required in the AOC (USEPA, 200Ia)? Need to work onreasoning about OU2 SLERA. See comments enclosed from Natural Resources Trustees foroverall concerns.

00642622-Final 17 of 71 7/16/2004



Response 26:

Remediation activities for OU-3 were not required in the AOC. The reference to remediationactivities at OU-3 that were conducted under the AOC will be removed from the revised RI/FSWork Plan.

This section of the RI/FS Work Plan referred to in the comment summarizes the findings of theOU-3 SLERA. The SLERAs for the OU-l/OU-2 area as well as OU-3 are presented in theAppendices E and F of the RI/FS Work Plan. Specific responses to comments on these twoSLERA documents are provided in response to Comment Nos. 23-26, 44, 52, 62, 69-86, and 90-94.

COMMENT 27:


The RAO of addressing COPC concentrations in Choccolocco Creek fish is too narrowly focused.Wildlife can be exposed to a wide variety of prey types in addition to fish. Even if thecontaminated fish disappeared there would still be exposure to wildlife.

Response 27:

The text of the RI/FS Work Plan will be clarified to reflect biota in general.

COMMENT 28:


Air should also be identified as a media of concern that will be addressed through actions to soil,sediment, and/or groundwater.

Response 28:

The RI/FS Work Plan will be modified to reflect that air will be considered in the RI/FS processfor the Site. While air is not a primary media of concern, Figure 4-3 of the Phase ICSM Reportidentifies air as a potential pathway that will be carried through the RI/FS process.

This section of the RI/FS Work Plan will be revised to reflect that while air is a pathway that willbe carried through the RI/FS process, no specific remedial alternatives for air alone arecontemplated. The text will reflect that remedial actions taken for other media are expected toreduce PCB concentrations in air.

COMMENT 29:


Second sentence should not be included if it is intended to limit the area where groundwaterconditions are evaluated.

00642622-Final 18 of 71 7/16/2004



Response 29:

This section of the RI/FS Work Plan presents preliminary remedial alternatives and is notintended to address the scope of groundwater investigations conducted under the RI/FS process.

COMMENT 30:


Data is needed in OU1 to evaluate the nature and extent of contamination in all media that affecthuman health and the environment. For the most part, this is expected to center on PCBs. Somesamples will be tested for a wide range of compounds to ensure that the risk from othercontaminants that may have escaped the site can be quantified. Some of those data needs may beaddressed through other data gathering events (i.e., groundwater, surface water, and air datagathered for OU2 may be used in OU1 analysis), but the data is still needed to quantify'residential risk. This section needs to be re-written.

Response 30:

This section will be revised to indicate that data for OU-1 is required to evaluate the nature andextent of contamination in all media that affect human health and the environment. The data willbe collected as part of the NTC Removal Action and as part of the OU-2, OU-3 and OU-4investigations. When the NTC Removal Action is completed and other data needed for OU-1have been collected, the data will be presented in a Site Characterization Report for OU-1.

COMMENT 31:

Section 3.5.2, page 3- 7 '

Data is needed in OU2 to evaluate the nature and extent of contamination in all media that affecthuman health and the environment. All media, including air, ground water and surface water,need to be evaluated, through this or another operable unit.

Response 31:

The Parties agree that these data are needed to conduct the RI/FS. Based on an assessment of theexisting data presented in the Phase I CSM Report, the additional data needed to conduct theRI/FS for OU-2 are identified in the OU-2 FSP that was submitted to the USEPA on June 4,2004.

r—-COMMENT32:


The text states that methods to evaluate potential migration of groundwater from the Facility willbe considered during preparation of the FSP for this OU. It was this revie\ver's understandingfrom notes taken from the April 13, 2004 meeting in Anniston that all groundwater issues,

00642622-Finnl 19 of 71 7/16/2004



including off-site migration to OU-1 and OU-2. will be addressed as part of the OU-3investigations. Please clarify.

Response 32:

The potential for groundwater to be directly migrating from the Facility will be evaluated underOU-3. The potential for groundwater issues away from the Facility will be addressed on an OU-specific basis.

The following two sentences will be added to the end of the first paragraph on page 3-8.

"Groundwater in OU-2 that is part of a plume migrating from OU-3 will be addressed in OU-3and not OU-2. If there are groundwater issues in OU-2 that are not related to a plume migratingdirectly from the facility, those issues will be addressed on an OU-specific basis."

COMMENT 33:


The text states: "A revie\v of available data on COPCs in soil indicates that nature and extent iskttown ", although additional data are needed for the human health risk assessment. However,this statement is contradicted in Section 3.5.3.1 Soil, page 3-10, 2nd paragraph, where the textstates that subsurface data are limited, and additional surface soil data are needed becauseprevious sampling locations were biased toward areas of suspected contamination. This wouldindicate that the extent of contamination is not kno^vn. The statement in section 3.5.2 should beremoved.

Response 33:

The Parties will revise the text in Section 3.5.2 to read:

"A review of available soil data for OU-3 indicates that additional data are needed for sitecharacterization and risk assessment purposes."

COMMENT 34:

Section 3.5.3.3

Although the work plan acknowledges evidence that groundwater contamination may bemigrating off the Facility, the plan does not go far enough in the investigation of that possibility.One of the primary objectives of this RI is to confirm the nature and extent of releases. To dothis, as a first step, current COPC (i.e., Table 1 of the CD) concentration data are needed for allthe perimeter monitor wells. If data is not available, it is recommended that, in addition to thesampling of the temporary monitor wells that have been proposed for this RI, any perimetermonitor well (i.e., OW-06A, OW-07, OW-09, OW-10, OWR-01S, MW-07, OW-21A, OW-22, MW-08, MW-9A, MW-14, and OWR-10) that has not been sampled and analyzed for the full list ofCOPCs within the past 2 years be sampled and analyzed for the full list of COPCs during this RI.In addition, because there is significant evidence that contaminants may be migrating Off-

00642622-Final 20 of 71 7/16/2004



Facility in the area ofOW-07 and OW-09 and because of the large distance bet\veen OW-07 andOW-09. an additional temporary monitor well should be installed midway behveen these twomonitor wells. If any contamination is found above the appropriate risk-based criteria in any ofthese perimeter wells, determining the extent of this Off-Facility contamination should thenproceed with temporary wells as proposed. Permit concentration limits do not apply to thisinvestigation. Conservative risk-based criteria and/or MCLs should be used to define the extentof contamination.

Response 34:

All perimeter monitoring wells that have not been sampled and analyzed for the full list ofCOPCs within the past 2 years will be sampled and analyzed for the full list of COPCs during theRI. Each of the wells listed in the comment has already been sampled within the past two yearsor is proposed to be sampled as part of the RI except for MW-14. Sampling of MW-14 will beadded. The following sentence will be added at the end of the third paragraph in Section 3.5.3.3.1of the revised RI/FS Work Plan:

"Additionally, MW-14 will be sampled for the full list of COPCs to further evaluate the natureand extent of releases in this area."

The Parties disagree with the commenter that "there is significant evidence that contaminantsmay be migrating Off-Facility in the area of OW-07 and OW-09." Although PCBs have beendetected at interior wells near OW-07 and OW-09, these on-Facility wells were installed in areaswhere high levels of PCBs were to be expected. At each of these areas, wells located atdowngradient perimeter locations have not shown elevated concentrations that indicate impactedgroundwater is migrating from the Facility. While the lateral distance between OW-07 and OW-09 maybe considered large (i.e., approximately 600 feet), the direction of groundwater flow in thevicinity of the two wells is to the north with a slight northeast component near OW-9 (see Figure2-7 in the RI/FS Work Plan). Therefore, when taking into account the direction of groundwaterflow, the equivalent spacing between the two wells is less than 150 feet which is adequate toestablish perimeter control. No additional wells are considered necessary in this area.

While Permit Concentration Limits (PCLs) do not specifically apply to this investigation they dorepresent a conservative concentration limit for those constituents that do not have an establishedMCL. The PCLs for all constituents except parathion, o,o,o-triethylphosphorothioate, phenol,and PNP were established as the detection limit for that constituent. Risk based concentrations(RBCs) were derived for parathion, o,o,o-triethylphosphorothioate, phenol, and PNP usingstandard USEPA methods.

For the OU-3 RI/FS investigation, the Parties will use MCLs as an initial comparison tool. Forparameters that do not have established MCLs, PCLs will be used.

COMMENT 3 5:


Please provide a figure showing the locations of the seven deep residuum monitor wells and atable presenting the results of the analyses.

00642622-Final 21 of 71 7/16/2004



Response 35:

Figure 3.1 and Table 3.1 showing the locations of the seven deep residuum wells and the resultsof the analyses for these wells will be added to the RI/FS Work Plan as requested. References tothe figure and table will be included in Section 3.5.3.3.

COMMENT 36:

Section 3.5.3.3

The Work Plan concludes that groundwater contamination at the Facility does not extend to thedeep residuum. There does not appear to be sufficient evidence to make this conclusion,particularly in the South Landfill area. Significant groundwater contamination was found inOWR-5D, a deep residuum monitor well located in the South Landfill area. There is speculationthat because this monitor well is located within the line of interceptor wells which are alsoscreened in the deep residuum, the contamination found in OWR-5D is due to the pull-down ofcontamination by the interceptor wells into the deeper zone, and not due to natural migration ofcontamination into and through the deeper zone. While this may be the case, we do not know forsure how this contamination got there and because there are no other current deep monitor wellcontamination data for the South Landfill area, we still don 't know if contamination is migratingfrom this source area through the deep residuum. Therefore, at least one deep residuum monitorwell should be installed down gradient of the South Landfill, outside the influence of theinterceptor well system. Because significant contamination was found at OW-16A, at a minimum,a deep residuum monitor well should be installed adjacent to this shallow residuum monitor welland sampled for the full list ofCOPCs.

Text states that, although OWR-7D is impacted, levels of contamination have been decliningduring the 2-year monitoring event. The explanation presented for this decline is that the sourceof contamination was drag-down of contamination during the installation of the well. Analternative explanation may be that contamination decreased following the installation of themulti-media cap, which decreased head and infiltration. If this alternative is correct, there couldbe a "slug" of contamination down gradient of the OWR-7D. Due to the low groundwater flowvelocities, this contamination is not likely to have moved very far. Presently, the closest deepresiduum monitoring well located down gradient of the West End Landfill is over a thousand feetaway. An additional deep residuum monitoring well should be installed at the perimeter of thesite, north ofOWR-7D and south of Adams Street, to monitor this zone.

Response 36:

Deep residuum monitoring wells OWR-1D and OWR-6D are currently located down-gradient ofthe South Landfill and monitoring well OW-16A. As noted in the response to Comment No. 9,no groundwater impacts were detected in these wells and contamination detected in OWR-5Dwas likely caused by draw-in from the extraction wells located in its immediate vicinity. Anycontamination present near OWR-5D is being captured by the SWMU 1 Corrective ActionSystem. If any contamination does extend beyond the influence of this groundwater recoverysystem, down-gradient monitoring wells indicate that the contamination is not migrating off of

00642622-Final 22 of 71 7/16/2004



the Facility. Therefore, an additional deep residuum monitoring well at this location is not ^_warranted. <****/

The West End Landfill was capped in 1996 and monitoring well OWR-7D was installed in 1998.Monitoring well OWR-7D is approximately 45 feet downgradient from the edge of the coversystem. Unretarded groundwater velocities in the area of the landfill are approximately 5-10ft/yr. Therefore, there would not have been sufficient time for a slug of potentially impactedgroundwater to migrate beyond the location of OWR-7D as a result of the multi media cap.

The hypothesis that decreasing PCB concentrations in monitoring well OWR-7D is a result ofslug movement is unlikely due to the strong affinity for PCB molecules to bind to soil particles.Even with contaminants with less of an affinity to bind to soil particles, persistence ofcontaminant concentrations in source areas is common. Consequently, the explanation of dragdown during well installation is more reasonable.

As indicated in response to Comment No. 22, extensive monitoring in the vicinity of the WestEnd Landfill indicates that groundwater is not impacted.

COMMENT 37:


More delineation is needed to determine the source of ground water contamination. Just becausethe contaminated ground water is inside the plant boundary does not mean there is no need toinvestigate sources. Ground water contamination has been found Off-Facility, contrary to whatis said in this section.

Response 37:

Beginning in approximately 1979, Monsanto initiated several investigations at the Facility as partof a company-wide program to evaluate environmental conditions and to develop information tosubmit in its Part B RCRA permit application. Monsanto previously operated, and subsequentlyclosed, two waste management areas (WMA-I and WMA-II) at the Facility in accordance withthe provisions of permits issued by the USEPA and ADEM. Investigations have been conductedto assess the extent of impacts resulting from the operations of WMA-I and WMA-II and toevaluate potential impacts associated with former operations of the OLBSI and the West EndLandfill (SWMU 47). Each of the investigations and corrective measures implemented inresponse to these investigations is described in Appendix A of the RFI/CS Work Plan. Duringthe RFI/CS investigation, a series of shallow and deep residuum monitoring wells were installedto assess sources of contamination and whether contaminants were migrating off of the Facility.After the investigation, it was concluded that three areas inside the Facility (SWMU 42, AOC-C,and SWMU-12) warranted further investigation because there were no monitoring wells locatedimmediately downgradient of these areas, and the wells being used to establish perimeter controlwere too far from the areas to adequately evaluate and monitor the groundwater quality fromthese units. During the Supplemental RFI investigation, monitoring wells OWR-11 throughOWR-13 were installed to address these issues by providing monitoring points downgradient ofSWMU 42, AOC-C, and SWMU-12.

00642622-Final 23 of 71 7/16/2004



The Phase I CSM Report recognizes that, within the property boundaries, there have been manydifferent industrial processes and waste disposal practices over the 80 years of the Facility'soperation. The location of hot spots within the Facility has been investigated and this informationhelped to determine the perimeter monitoring strategy. As discussed in the Phase I CSM Reportand approved by USEPA, the Facility is considered a single source for groundwater impacts, andgroundwater control is being implemented at the Facility perimeter.

Groundwater impacts have been noted off of the Facility proper in only one area, which is in thevicinity of OW-21A. While this well is still on Solutia-owned property, an investigation todetermine the down-gradient extent and possible sources is proposed in the RI/FS Work Plan andthe OU-3 FSP.

COMMENT 3 8:

Section 3.5.3.3.2, page 3-14

Why does this section limit the discussion of groundwater contamination to PCBs? There wereseveral other contaminants found in these areas at significant concentrations.

Response 38:

In the second sentence of the last paragraph of Section 3.5.3.3.2, 'PCBs' will be replaced with'the COPCs'. Also, the following paragraph will be inserted as the first paragraph in Section3.5.3.3.2.

"Monitoring well OW-16A has had detections of cobalt, chlorobenzene, 1,2-dichlorbenzene, 4-nitrophenol, and parathion. Parathion and chlorobenzene have also been detected in monitoringwells OW-8A and OW-15. With the exception of cobalt and 1,2-dichlorobenzene, each of thesedetections has been below either the respective MCLs or the PCLs for analytes that have noestablished MCLs."

For further information concerning the PCLs please refer to response to Comment No. 34.

COMMENT39:

Section 3.5.3.3.3, page 3-15

The implication in the text is that recently-installed well OWR-10 (located down gradient ofWEL-03 according to the pre-supplemental RFI potentiometric surface map) is monitoring thearea down gradient of WEL-03 where consistent low-levels of PCBs have been detected.However, OWR-10 is not down gradient of WEL-03 according to the revised potentiometricsurface map (see Appendix B). A shallow residuum well along the perimeter of the site (AdamsStreet), down gradient of WEL-03 should be installed.

Note: The text states that "PCBs have not been detected in recent sampling events at monitoringwell OWR-10", the analytical results shown in Table 2- 3 indicate that 1.8 ug/l of Aroclor wasdetected in that well. Please provide a sampling date on the Table.

00642622-FinQl 24 of 71 7/16/2004



Response 39:

As discussed in response to Comment No. 22, sufficient monitoring has been performed aroundthe West End Landfill to indicate that COPCs are not present in the groundwater. Data are alsopresented in response to Comment No. 22 regarding OWR-10. Additional well installation and _—additional sampling are not warranted in this area of the Facility. —

Table 2-3 will be revised to indicate that the sample results shown were collected as part of thesupplemental RFI/CS investigation sampling program conducted in February 2003.

COMMENT 40:

Section 3.5.3.3.3, page 3-15

The last sentence should be rephrased. The West End Landfill is being investigated in the RI/FS.The April 2004 data will help determine if additional data is needed for the RI/FS.

Response 40:

As indicated in response to Comment No. 22, the spring 2004 semi-annual monitoring data forthe West End Landfill are currently available and are attached with this response to commentsdocument. The data will be submitted in the Semi-Annual Sampling Report due in August 2004.The Parties will revise the last two sentences in the second paragraph in Section 3.5.3.3.3 to readas follows:

"The most recent results for OWR-7D (a deep residuum well in the vicinity of the West EndLandfill) indicate a decreasing trend in PCB concentrations to below the detection limit. Giventhat all wells in the vicinity of the West End Landfill have no COPCs reported above anyregulatory level, the Parties recommend no further investigative activities for groundwater in thisarea. The existing data will be further summarized in the Site Characterization SummaryReport."

COMMENT 41:

Section 3.5.3.3.4, page 3-15

The South Landfill is being investigated in the RI/FS. The work plan proposes that prior groundwater sampling results are sufficient to determine the nature and extent of contamination.However, ground water from the South Landfill will be evaluated during the RI/FS. See previouscomments concerning the need for monitoring of the deep residuum zone down gradient of thislandfill.

Response 41:

The need for monitoring opf the deep residuum zone downgradient of the South Landfill isdiscussed in the response to Comment No. 36.

00642622-Final 25 of 71 7/16/2004



COMMENT 42:

Section 3.5.3.3.5, page 3-16

Please attach EPA 's letter about congeners. EPA requested that PCB congeners, dioxins, andTCL and TAL parameters be analyzed for at least ten ground water samples, collected fromlocations where PCBs have been detected (e.g., OW-21, OW-08, etc.) and from points along thesame flow path from the site, if possible. The purpose is to ensure there are no othercontaminants of significant concern in ground water and to assist in determining the possibleeffects of weathering of PCB congeners.

Response 42:

The USEPA's letter about performing congener analyses will be included as an attachment to theRI/FS Work Plan. The Parties have agreed to collect groundwater samples and analyze thesamples for a broad suite of analytical parameters including PCB congeners at three samplelocations chosen to represent high, medium, and low PCB concentrations along a single flow line.There are only eight wells where the most recent sampling results for that particular wellindicated PCBs were present (i.e., OW-8A, OW-16A, OW-21A, OW-22, OWR-11, OWR-12,OWR-13, and OWR-5D). The proposed number of samples should be sufficient to determine the *s&io/fr •possible effects of weathering for specific PCB congeners. Based on a review of the results g>Cf^vobtained during the investigation, additional wells may be sampled for the expanded parameter uJX^j^list. *~

The following sentence will be added at the end of Section 3.5.3.3.5:

"Based on a review of the results obtained during the investigation, additional wells may besampled for the expanded parameter list."

COMMENT 43':


Surface water data will be needed. Ground water data will be needed around significant soilmanagement areas, such as Oxford Lake Park. The work plan provided limited detail onassumptions and models that will be used. To support the claim that PCBs in sediments aredeclining in concentration due to burial, collection and/or methods for interpretation of existingsediment cores should be provided to estimate the rate of sedimentation/burial. An assessment isrecommended of whether any additional data are needed.

Response 43:

The process for refining the data gaps for OU-4 is presented in Section 4.8 of the RI/FS WorkPlan and includes an evaluation of soil, habitat, and surface water data that have been collectedsince the Off-Site RFI Report was submitted in June 2000. These data will be presented to theUSEPA prior to and as a part of developing the supplemental FSP for OU-4. If additional surfacewater data are needed to complete the RI/FS process for OU-4, the data gap will be identified inthe supplemental OU-4 FSP.

00642622-Final 26 of 71 7/16/2004



While data have been collected to evaluate the rate of sediment deposition rates, this section ofthe RI/FS Work Plan does not reference them. For further reference, these estimates are providedin Section 3.4.2.5 of the Phase ICSM Report. Models that will be used in RI/FS process for OU-4 will be identified and evaluated in the Task 3 Technical Memorandum on Modeling of SiteCharacteristics as described in Exhibits A and B of the CD

COMMENT 44:


Before deciding on the biota to sample, a conceptual model of how wildlife are exposed should bedeveloped. The biota sampled should reflect the prey items of the receptors who are most likelyto be exposed. Different types offish samples (tissue type, species) will be needed to supportlong-term trend analysis, fish consumption advisories, and the ecological risk assessment.

Response 44:

The FSP for OU-4 addressed a very specific activity - one that is associated with supplementingthe continuing long-term monitoring program conducted by ADEM. The commenter is correct,and additional factors must be considered when identifying the type of biota that need to besampled in order to obtain data suitable for human and ecological risk assessments. These factorswill be identified and used in subsequent activities within OU-4 when the investigation of thisOU is initiated. This comment addresses activities that will be conducted when OU-4investigation and characterization efforts are initiated. These considerations for ecologicalreceptors will be included in the development of a sampling plan to support the ecological riskassessment for OU-4.

COMMENT 45:

Section 4, page 4-1

The SAPP, QAPP, and HASP that have been reviewed for OU1 were for the Non-Time CriticalRemoval. The site wide QAPP and HASP should apply to RI/FS activities for OU1, if needed.Please provide an explanation if that assumption is incorrect.

Response 45:

The revised RI/FS Work Plan will be modified to reflect that the Site-Wide QAPP (BBL, 2004)and Site-Wide HASP (BBL, 2004) apply to the site as a whole including OU-1.

COMMENT 46:

Section 4.5

If ground water, air, surface water, sediment, and biota data are collected as part ofOU2, OU3,and OU4, there may not be a need for a FSP for OU1, but there should be a SiteCharacterization Report for OU1 that summarizes all the data for the human health risk

00642622-Final 27 of 71 7/16/2004



assessment. Since residential soils are being cleaned up through the NTC Removal Action, the95% upper confidence level for PCBs in soil can probably be assumed to be no greater than 1.0mg/kg. When data needed from other plans is available, the OU1 Site Characterization reportshould be prepared. There is no need for a draft and final Site Characterization Report. Thereport is essentially a data report and when approved (meaning, everyone agrees that noadditional sampling is needed) will become the basis for the HHRA, ERA and RI. The DraftHHRA will be complete 60 days after approval of the Site Characterization Report.

Response 46:

Section 4.5.2 will be revised to read as follows:

"...for the Anniston Lead Site, a separate area. Other data requirements for OU-1 will becollected as part of investigations conducted for OU-2, OU-3, and OU-4. Data collected by theParties for OU-1 have historically been reported through the monthly progress report processunder the Removal Order, and data collected under the OU-1 SSAP will continue to be reportedon a monthly basis. When the NTC Removal is completed and other data needed for OU-1 havebeen collected, the data will be presented in a Site Characterization Report for this OU. Thereport will be a data report and when approved will become the basis for the HHRA, ERA, andRI. The Draft HHRA_will be completed within 60 days after approval of the SiteCharacterization Report."

COMMENT 47:


This section should be corrected to reflect that the SRE was performed only for residentialexposure to contaminated soils. A full HHRA will be conducted to assess residential exposure toall contaminated media.

Response 47:

The Parties will revise the RI/FS Work Plan noting the limited nature and purpose of the SRE.

COMMENT 48:

Section 4.6

Although ground water is essentially being investigated in OU3, there are areas, such as the soilmanagement areas at the Quintard Mall, in OU2 where ground water needs to be characterized.Air data is needed in offsite areas for use in the HHRA and ERA.

Response 48:

The text of this section of the RI/FS Work Plan will be revised to indicate that "Investigations forgroundwater will be included in the OU-2 FSP" Similarly the text of the RI/FS Work Plan will berevised to reflect that it will include air sampling to verify the results of earlier samplingconducted by the USEPA.

00642622-Final 28 of 71 7/16/2004



COMMENT 49:


When data needed from other plans is available, the OU2 Site Characterization report should beprepared. There is no need for a draft and final Site Characterization Report. The report isessentially a data report and when approved (meaning, everyone agrees that no additionalsampling is needed) will become the basis for the HHRA, ERA and RI. The Draft HHRA will becomplete 60 days after approval of the Site Characterization Report.

Response 49:

As identified in Exhibit A of the CD, the RI/FS Work Plan will be revised to reflect that a draftPreliminary Site Characteristics Summary will be prepared and submitted when data needed fromother plans becomes available. Although a final version may be necessary (as identified inExhibit A of the CD) the Parties recognize that if the draft version is approved by the USEPA afinal version will not be required.

COMMENT 50:

Section 4.6.3.1.1,page 4-10

Rephrase paragraph to indicate that a full screening of contaminants will be analyzed on a subsetof samples to ensure that the COPC identified in the RFI/CS and Conceptual Site Model are thechemicals that could define releases from the Facility. Similar subsets will be generated in alloperable units, even though some contaminants may be detected offsite that are not present as aresult of releases by Solutia/Pharmacia.

Response 50:

This section of the RI/FS Work Plan will be revised to reflect that "A subset of samples will becollected during the RI/FS and evaluated for the range of constituents listed in the USEPA's letterdated March 13, 2003 to confirm preliminary conclusions regarding COPCs presented in thePhase ICSM Report.

COMMENT 51:


While it is appropriate to use the Fort McClellan (FTMC) background data set because of thesimilarity of soil types and close location to Solutia, the presence of munitions ranges at FortMcClellan may mean that some of the data may not be representative of background. Hence, theFTMC background data set should be carefully examined for possible high outliers that mayrepresent presence of old munitions or other military-related chemicals rather than truebackground. In addition, care should be taken in screening inorganic chemicals that may havebeen used in chemical manufacture at Solutia.

00642622-Final 29 of 71 7/16/2004


Anniston PCB SiteUSEPA ID No. ALD000400123 and ALD0040 19048

Response 51 :

The background metals survey conducted at Fort McClellan was specifically designed todetermine natural background conditions for the area. Munitions ranges and other suspect areaswere specifically excluded when collecting samples for this study. However, the data will be "_>*•'reviewed to identify any possible outliers. If any are identified, the particular constituent(s) will ^^be investigated to determine if it could be associated with "human activities" specific to FortMcClellan (i.e., munitions-related chemicals). If the constituent is not site related, the value willbe retained, which is consistent with the USEPA guidance on defining background (USEPA,2002). Regarding screening inorganic chemicals, these constituents are eliminated if the detectedconcentrations are within background levels, and thus there is no indication that activities at theFacility contributed to the environmental levels.

COMMENT 52:


EPA agrees that OU1 And OU2 can be combined for the SLERA, however EPA does not agreethat habitat quality and limitations for residential areas is the same as commercial areas.Commercial areas covered in paving and buildings is very different habitat. Conclusions arepremature without the additional data to be gather in the FSP.

Response 52:

As discussed in response to Comment No. 24 both OU-1 and OU-2 share similar habitat qualities |\_0Jr< rand limitations, are contiguous, and there are no significant barriers between them. Given thecontiguous nature of OU-1 and OU-2, and that these areas do share many physical similarities,adequate information on urban species can be obtained by surveying the more readily-accessibleproperties in OU-2. Also, survey locations will be positioned so as to obtain information fromboth OUs in those areas where regions of OU-2 are in close proximity to OU-1. Thus, a speciessurvey for OU-2 should reasonably approximate the species distribution at OU- 1 .

COMMENT 53:

Section 4. 7.3.1, page 4-16

Rephrase paragraph to indicate that a full screening of contaminants will be analyzed on a subsetof samples to ensure that the COPC identified in the RFI/CS and Conceptual Site Model are thechemicals that could define releases from the Facility. Similar subsets will be generated in alloperable units, even though some contaminants may be detected offsite that are not present as aresult of releases by Solutia/Pharmacia.

Response 53:

As noted in response to Comment No. 50, data will be collected for a range of constituents basedon the CD and the USEPA letter dated March 13, 2003. The revised RI/FS Work Plan will berevised to say that the results of these analyses will be compared against the Facility list contained

00642622-Final 30 of 71 7/16/2004



in Table 1 of Appendix F of the CD to evaluate the results of the COPCs presented in the Phase ICSM Report

COMMENT 54


Most of the adjustments to exposure identified as being appropriate in the HEA are riskmanagement decisions in the CERCLA process. It may be appropriate to describe them, but it isnot the process that will be followed in the HHRA.

Response 54:

Both CERCLA and RCRA guidance provide opportunities for site-specific considerations whendeveloping exposure parameters. Because the current and reasonably anticipated future use of thefacility area (i.e., OU-3) is well known and characterized, it is appropriate to incorporate exposurevariables reflective of these land use activities into the risk assessment process. In cases wherethe current or reasonably anticipated future use is not known or the OU is not under the control ofthe Parties (e.g., OU-2), the use of site-specific exposure parameters may not be appropriate.There are certain unique characteristics of the facility that should be taken into consideration toreduce uncertainty in the estimates of risk to workers and visitors to the plant.

COMMENT 55:

Page 4-19

At the meeting held on April 13, 2004, it was stated that there is no zoning in Anniston, per se.Page 4-19 of the work plan states that the property is zoned for industrial use. Please clarify.

Response 55:

Plant deed restrictions are discussed in the RFI/CS Report, and a copy of the deed restriction isprovided in Appendix J-3 (Golder, 2002). Deed restrictions limit use to industrial use, restrict useof groundwater underlying the site, and have been recorded in the Deed Book for CalhounCounty. Also, note that designated WMAs were previously deed restricted/recorded inconjunction with the facility's RCRA Part B Permit application. The comment regarding zoningin the April 13'2004 meeting reflected the practical difficulties in tracking zoning in the Annistonareas where vacant or residential properties are often converted to commercial properties.

COMMENT 56:

Section 4.8,page 4-22

Emphasis that fish tissue collection using previously approved methodology is being proposed.That collection program might be modified in a Supplemental FSP.

00642622-Final 31 of 71 7/16/2004



Response 56:

The revised RI/FS Work Plan will reflect that modifications to the previously approved fishcollection program may be necessary.

COMMENTS?:

Section 4.8, page 4-23

Issue of having a ROD in place for OUI-3 before preparing the FS for OU4 needs to beevaluated further before being included in the work plan.

Response 57:

This statement in the RI/FS Work Plan reflects the explicit linkage between remedial actionstaken in upstream areas of the Site (i.e., OUs 1, 2, and 3) and the range of potential remedialalternatives considered for the downstream areas of the Site (i.e., OU-4). This approach is alsoconsistent with recent USEPA guidance Principles for Managing Contaminated Sediment Risksat Hazardous Waste Sites (USEPA, 2002) for sediment sites that identifies the need to firstaddress potential upstream sources. As stated in the guidance document "Lack of source controlmight make sediment remediation efforts to reduce site-specific risks unsuccessful. " The methodproposed in Section 4.8 was intended to ensure this guidance was followed.

COMMENT 58:


EPA proposes that Solutia/Pharmacia set up four quarterly meetings, (October 2004, January2005, April 2005, and July 2005) with all state and federal parties to discuss the FSP and theSupplemental FSP with a target of September 2005 for finalization of a Supplemental FSP forOU4. RAOs, endpoints, and the Conceptual Site Model need to be discussed prior to finalizationof a supplemental FSP for OU4.

Response 58:

The Parties agree to meet to discuss the development of the FSP documents for OU-4 and that theRAOs, endpoints, and the Phase I CSM Report are central to reaching agreement on the scopeand approach for the OU-4 FSP documents. The target dates of October 2004 for a meeting andSeptember 2005 for a final supplemental FSP proposed in the comment appear reasonable, butnote that the target date for the supplemental FSP is dependent on the approval of otherpreceding documents including the RI/FS Work Plan.

COMMENT 59:


The type of modeling that is to be performed (e.g, sediment transport, etc.) should be stated inthis section.

00642622-Final 32 of 71 7/16/2004



Response 59:

The text of the RI/FS Work Plan will be updated to reflect the types of models that will beconsidered in this evaluation. Consistent with Exhibits A and B to the CD, these models will beidentified and evaluated under the Task 3 Memorandum on Modeling of Site Characteristics thatwill be completed for each OU. It would be premature to identify specific models in the RI/FSWork Plan given the sequence of activities for OU-4.

COMMENT 60:

Section 4.8.4.1

Be aware that the community and ATSDR have raised concerns about bioaccumulation ofPCBsin livestock raised on the contaminated flood plain. If any prior testing has been done to addressthis issue along Choccolocco Creek, please provide it.

Response 60:

This potential exposure pathway was specifically identified in the Phase I Conceptual Site Modeland therefore will be quantitatively evaluated. Initial information on the Choccolocco Creekfloodplain indicates that distributions of PCBs are limited and therefore the significance of thisexposure pathway is potentially minimal. However, the agricultural exposure pathway will beinvestigated in detail when the FSP for OU-4 is developed.

COMMENT 61:

Section 4.8.4.2.1

What are the PA, SI and ESI documents referred to in this section?

Response 61:

The revised RI/FS Work Plan will be modified to reflect that the Parties do not have PreliminaryAssessment (PA), Site Investigation (SI) and Expanded Site Investigation (ESI) data. Data usedfor the OU-4 SLERA were gathered using the USEPA approved work plans for variousenvironmental investigations including RCRA- and AOC-related investigations and permitmonitoring programs.

COMMENT 62:

Section 4.8.4.2.3

Will there be a separate work plan and sampling and analysis plan for the ecologicalinvestigation?

00642622-Final 33 of 71 7/16/2004



Response 62

Specific data requirements for the ecological risk assessments will be defined under OU specificwork plans.

COMMENT 63:

Section 4.8.5.1

RAOs needed to be established to evaluate downstream issues and to determine if the CoosaRiver needs to be addressed.

Response 63:

Downstream issues are addressed by the RAOs presented in Section 3.2.1 of the RI/FS WorkPlan. With regards to the Coosa River, this area is currently outside the confines of the RI/FSWork Plan as the downstream end of OU-4 is the confluence of Choccolocco Creek and LakeLogan Martin. As noted in the Phase I CSM Report PCB concentrations are not detected in thesurface sediment of Lake Logan Martin and PCB concentrations in fish tissue continue to declineand are on average below the state of Alabama fish consumption guideline of 2 mg/kg. Inaddition, there are upstream sources of PCBs to and in Lake Logan Martin that result inbackground PCB concentrations in the Lake.

COMMENT 64:

Table 5-1

Just because the EE/CA was conducted, doesn 't preclude the need to develop and screenalternatives with remedial, not removal, criteria. Revise Table to reflect changes due tocomments above.

Response 64:

Table 5-1 will be revised to reflect changes made to the RI/FS Work Plan as part of theseresponses to comments and this specific comment, including the consolidation of OU-1 and OU-2into a single OU.

COMMENT 65:

Table 6-1

Revise Table to reflect changes in comments above. Also, Table 6-1 refers to deliverables. Theterm "deliverable" has a specific meaning in the CD. Please make sure that the use of"deliverables " on Table 6-1 does not contradict the terms use in the CD.

Response 65:

The table will be revised to reflect the comment.

00642622-Final 34 of 71 7/16/2004



COMMENT 66:

Treatability Study/Pilot Testing should be an option for every operable unit.

Response 66:

The RI/FS Work Plan will be updated to reflect the potential option of performing treatabilitystudies for each OU.

COMMENT 67:

Figure 2-20

Figures 2-20 shows Facility area the same as Solatia owned property. This might be confusing tothe public. What are the t\vo large areas of Solatia owned property that are separated from theplant and adjacent properties. What were those properties used for?

Response 67:

The On-Facility area will be revised on Figure 2-20 to be consistent with that submitted andapproved as part of the Phase ICSM Report.

The two large areas of Solutia-owned property that are separated from the plant and adjacentproperties will not be included on Figure 2-20. One of these properties was a former borrow pitlocated off Eulaton Road, and the other was mistakenly identified as a Solutia-owned property.

COMMENT 68:

Figures

Show areas in OU2 where contaminated soils are being managed. There is no Figure 6-1showing the project organization.

Response 68:

A new figure will be added that shows areas in OU-2 where PCB-containing soils are beingmanaged. The areas that will be shown on the figure include: 1) the Central Staging and SoilManagement Area, which will include PCB-containing soils excavated as part of the NTCRemoval Action, and Quintard Mall area. In addition, a copy of Figure 6-1 showing the projectorganization will be included.

00642622-Final 35 of 71 7/16/2004

Responses to USEPA Comments on theRl/FS Work Plan, OU-3 FSP and OU-4 FSP


General Comments on the SLERAs

COMMENT 69:

The habitat/receptors information is lacking. Consequently the first steps of the risk assessmentprocess cannot properly be completed; therefore Solutia 's statements to the effect that 'no furtherstudy is warranted' for OUs 1,2,3 are premature, at best.

Response 69:

As indicated in Appendix E and Appendix F of the RI/FS Work Plan, species surveys will beperformed to reduce the uncertainty associated with the conclusions based on the habitat surveys.The Parties will revise the RI/FS Work Plan to reflect the additional work planned for OUs 1/2and 3. Also, any concluding statements will be removed from the SLERA until the informationfrom the proposed species surveys is collected and available for inclusion in the overallassessment of the site.

COMMENT 70:

The May 2003 Phase I Conceptual Site Model Report is more-or-less a data summary withinterpretation. There was no conceptual site model presented in the SLERA. Citing a previousreport is not sufficient for this document. The conceptual site model is normally presented aspart of the work plan and should be focused on pathways to be addressed in the risk assessment.It can be used as a vehicle to explain how the risk assessment will address various potentialexposure pathways.

Response 70:

The Parties will incorporate into the SLERA an ecological-specific conceptual site model in therevised RI/FS Work Plan. These models will be included in Appendix E and Appendix F.

COMMENT 71:

According to EPA 's guidance by this point in the project we expect to have reached agreement onthe chemicals of potential concern to be further evaluated in the risk assessment, assessmentendpoints and measures, and risk questions before initiating the work plan. The work plan isexpected to include all of the exposure parameters that will be used in the food chain models.EPA wants to see the toxicity profiles that support the toxicity reference values that will be used.This information is necessary to include in the work plan before it can be approved. Lack ofhabitat surveys should not impede this work.

Response 71 : (j^j^l ^ +U

The list of pCOPCs presented in Exhibit F to the CD titled Table I of the RI/FS Agreement has S0^ ' j^-been approved by ADEM and the USEPA in the On-Site RFI/CS Work Plan (Colder, 1 998) on tyf j .April 2 1 , 1 998, in the Off-Site RFI Work Plan (BBL, 1 999) approved by ADEM and the USEPA (L&fr I C

on August 5, 1 999, and in the Phase I CSM Report, approved by USEPA on March 5, 2004.

00642622-Final 36of7 l 7/16/2004



Assessment and measurement endpoints were identified as an ecological receptor foraging andreproducing in the OUs (Section 3.1.7). An unspecified ecological receptor was indicatedbecause the OUs have potentially limited habitat and are probably unlikely to harbor any specificresident species, although confirmation of this requires the results of the proposed speciessurveys. The proposed species surveys will confirm or reject that hypothesis. The measurementendpoints for this receptor were specified as adverse effects on growth, survival, andreproduction. The chosen toxicity reference values consisted of ecological screening valuesdeveloped by USEPA Region 4 (Section 3.1.8). A detailed discussion of the derivation processand of the toxicity profiles used to develop those values is well beyond the scope of SLERA.Presumably, the screening values, being a USEPA work product (USEPA, 2000), have alreadybeen peer-reviewed and approved by the USEPA staff and there is no need for additional reviewby the USEPA. However, a sentence will be added to the RI/FS work plan stating that consistentwith the USEPA guidance, following completion of steps 1 though 3a of the ecological riskassessment process, a Scientific/Management Decision Point will allow a determination ofwhether additional work (e.g., a baseline ecological risk assessment (BERA)) is required.

COMMENT 72: ul&

The manner in which data will be evaluated should be discussed in the work plan, specifically ifbiota-to-sediment accumulation factors will be used, how these will be derived.

Response 72:

The existing text in the SLERA for OUs 1 through 3 explicitly describes how data are handled.Sections 2.2.2 and 3.2.2 indicate in detail the treatment unqualified and qualified data receive andspecify that the maximum values are used in the screening analysis. There was no need forBSAFs, as data and screening benchmarks were available for the appropriate media.

COMMENT 73:

The SLERA lacked screening of concentrations in the wells, as we requested at the April 13meeting. Specifically, as there was a concern of EPA's that there could be contaminatedgroundwater discharging to surface water, we requested that Solutia take data from the nearestwells to surface water bodies, and screen them against Region 4 screening values for surfacewater (such as ambient water quality criteria) to address the potential for adverse effects.Comments provided at the March 9 and April 13 meetings are summarized:

• Provide information on predicted locations where specific contaminated ground waterwells may discharge to surface water.• Provide ground water elevation data for the wells closest to the 11th street ditch oneither side.• Screen in the SLERA the concentration data from the wells closest to the ditch againstsurface water screening benchmarks protective of ecological receptors.• Provide all dilution calculations.

Response 73:

Snow Creek represents the closest receptor where groundwater could discharge to surface water.

00642622-Final 37 of 71 7/16/2004

Responses to USE PA Comments on theRI/FS Work Plan, OU-3 FSP and OU-4 FSP


The 11 th Street Ditch, which is located immediately adjacent to the north end of the Facility, wasnot considered since it is a shallow ditch and it is in the process of being lined with shotcrete aspart of a USEPA approved Removal Action. Screening of concentration data from wells againstsurface water screening benchmarks for Snow Creek was performed during the RFI/CSinvestigation. Table 20 of the RFI/CS Report presents a summary of the comparisons of dilutedwell concentrations to benchmarks protective of ecological receptors (Region IV screeningvalues). Since Snow Creek is part of OU-l/OU-2, the discussion of the screening is presented insection 3.1.2 of Appendix E. Table 20 from the RFI/CS Report will be incorporated intoAppendix E.

Below is a summary of water level data for the monitoring wells and piezometers located closestto the 11th Street Ditch. It is noted that these data are not relevant to discharge of groundwater tothe 11th Street Ditch as the ditch is currently being lined with an impermeable material.

Wpll fin • ' : • ' • ' • ' •• ' • ' . ' • ' ' ','?

OW-18OW-19OW-20OW-21AOW-22OW-23OW-24MW-08MW-09AMW-14MW-15MW-16MW-20APZ-08DOP-1OWR-01DOWR-01S

TOC Elevation..(It. M1SL)

750.47748.72747.62742.83745.57747.53746.15746.80750.02751.30756.19755.70752.90750.51747.49739.59738.89

Depth toWotpr (ft

BTOC)11.2011.008.1514.1014.808.658.7013.8522.6015.3012.3030.609.3027.1566.7047.4016.05

ApproximateStick-up (ft.)

2.952.502.483.503.502.832.473.501.922.163.673.081.252.673.712.002.00

Water-LevelITIavatinn (ft

MSL) '..; ; . ; . , . - , .739.27737.72739.47728.73730.77738.88737.45732.95727.42736.00743.89725.10743.60723.36680.79692.19722.84

TOC - top of casingFt. MSL - feet Mean Sea LevelBTOC - below top of casing

This information will be presented in Section 2.2.3 (Facility Hydrogeology) after the discussionof the horizontal groundwater flow. In addition the dilution calculation will be included in thissection as a discussion of hypothetical groundwater discharge. The following paragraphs will beadded on page 2-8, after the results of the average groundwater flow velocity calculation arepresented.

"Groundwater leaving the facility would be expected to continue flowing in a horizontal directionuntil it eventually discharged into a surface water body. The 11th Street Ditch, which is located

00642622-Final 38 of 71 7/16/2004



immediately adjacent to the north end of the Facility, was not considered as a surface waterdischarge point for groundwater since it is a shallow ditch and it is in the process of being linedwith shotcrete as part of a USEPA approved Removal Action. Snow Creek is located to thenortheast of the facility. Although, groundwater flow is slow (4 ft/yr), it is expected to eventuallymake its way into Snow Creek and contribute to the base flow of the creek. .

To estimate the contribution of groundwater discharge from the facility, a slug of groundwaterwith a width of about 400 feet (distance between OW-9 and OWR-01S) and depth of 50 feet deep(approximate one-half the thickness of the residuum in this area) was assumed. The volumetricflow to the discharge zone is represented by the product of Darcy velocity (which is the hydraulicconductivity (8 x 10"2 ft/d) multiplied by the hydraulic gradient [0.015 ft/ft]) multiplied by thecross-sectional area (400 ft x 50 ft). Thus, the volumetric flow of our groundwater discharge is24 cubic feet per day (cfd).

Based on work conducted by BBL for the Off-Facility RCRA program, base flow in Snow Creekflowing above the discharge zone is on the order of 5 cfs (432,00 cfd). The total flow after themixing base flow with the groundwater discharge would be a summation of the two terms(432,000 cfd + 24 cfd), which equals 432,024 cfd. The effect of this discharge can be expressedas a volumetric percentage (i.e., the groundwater discharge represents an approximate volumetricincrease of 0.0056%). Stated another way, the base flow in Snow Creek is approximately 18,000time greater than the volumetric discharge of groundwater from the northeast portion of the site."

Appendix E - Comments

COMMENT 74:

Ecological habitat quality might come into play as a factor for risk managers to consider inremedy selection, however, the ecological risk assessment must consider risks through allexposure pathways before making a management decision. There clearly is potential forexposure at OUs 1 & 2. The creek bank areas where contamination tends to be highest also tendto have the highest potential for exposure to wildlife.

Response 74:

All potential exposure pathways were considered including soil, sediment, and stormwater. Theresults of SLERA showed that indeed arsenic, barium, beryllium, cadmium, chromium, cobalt,lead, manganese, mercury, nickel, vanadium, and total PCBs exceeded the screening criteria in atleast one of the three media. However, step 3a of the assessment allows further analysis of thesite setting, habitat limitations, etc., and identifies sites that do not warrant further study.Additional work is planned for OU-l/OU-2, as species surveys will be completed before theSLERA is considered complete. This information is considered as part of aScientific/Management Decision Point associated with Steps 2 and 3a (USEPA, 2000).

COMMENT 75:

Ground-water dilution assumptions and model calculations for Snow Creek should be provided.

00642622-Final 39 of 71 7/16/2004



Response 75:

Groundwater dilution assumptions and model calculations for Snow Creek are discussed inresponse to Comment No. 73.

COMMENT 76:

OUs 1&2 are home to many urban adapted wildlife, such as song birds, squirrels, raccoons,opossums, skunks, moles, shrews, etc. The potential risks faced by receptors exposed orpotentially exposed must be addressed. A decision that the habitat provided by OUs 1&2 is of 'lesser quality and hence these areas warrant reduced cleanup is a risk management decision thatcomes after the baseline risk assessment.

Response 76: y,, o\

The statement by the USEPA regarding wildlife species cannot be confirmed as there have notbeen any species surveys conducted on those operational units. It is expected that some parts ofresidential properties that contain narrow riparian habitat along the top of the creek bank mayprovide some habitat for species of songbirds and "urban" wildlife (e.g., skunks, raccoons,squirrels). However, these areas are somewhat isolated by surrounding dense, residentialcommunities (and other land uses), and therefore inhabitation by these species is constrained towhat limited habitat may exist in these areas. According to the guidance document (USEPA,2000), a decision to not go forward with the assessment may be made early in the risk assessment

.process (step 3a). This "reality check" uses information on area use factors, incidental soilintakes, background contamination, nature of contaminants, and ecological setting (USEPA,2000). In this assessment, given the limited areas of quality habitat and the extensive areas withpoor habitat quality associated with the land within OU-1 and OU-2, it is unlikely that anywildlife species communities would find the heavily residential and frequently disturbedproperties found there as an attractive locale to establish long-term feeding, nesting, andreproducing activities. Additional investigations in the form of species surveys are planned toreduce uncertainty associated with this determination. The details of these planned biologicalsurveys are provided in Section 5.1 of the OU-2 FSP which was submitted to the USEPA on June4, 2004.

COMMENT 77:

A detailed map of land cover would help identify areas with potential exposure to ecologicalreceptors.

Response 77:

Land cover information is presented in Figure 2-1 of the Phase ICSM Report.

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COMMENT 78:


Manganese is repeated in list of chemicals detected. It appears as if the text should read"magnesium " or "mercury. "

Response 78:

The text of the revised RI/FS Work Plan will be modified to read:

"...lead at a maximum concentration of 19,000 mg/kg, manganese at a maximum concentration of11,000 mg/kg, mercury at a maximum concentration of 28 mg/kg..."

COMMENT 79:


The compounds chlorobenzene, dichlorobenzenes (1,2- and 1,4-), dichlorophenol (2,4-),nitrophenol (4-), pentachlorophenol, phenol, sulfotepp, and tertrachloroethane (1,1,2,2-) weredetected at levels below limits of quantification. They were still detected. Their concentrationsshould be discussed and used in the risk assessment. J-qualified values are valid detections touse in a risk assessment.

Response 79:

These J-qualified data were used in the assessment, but were included in a separate grouping.According to the USEPA guidance (USEPA, 1989) qualified data can only be used for riskassessment purposes if the dataset contains at least one unqualified value. Appendix E of theRI/FS Work Plan will be revised to provide clarification.i

Appendix F - Comments

COMMENT 80:

EPA 's concern is for local populations and communities of receptors who are exposed to the site.The key is potential for exposure versus habitat quality. Receptors can become exposed throughforaging at OU-3 or by preying on animals that have foraged at OU-3. Receptors in the vicinityof the site can be exposed to fugitive air emissions. Residency is not required for exposure.Breeding populations on site are not necessary for exposure.

Response 80:

The Parties agree that residency is not required for exposure, but some kind of favorable habitatthat would provide areas of protection and attract these organisms is typically required for long-term exposure. Therefore, the residency argument refers to whether OU-3 is attractive enough toentice predators or prey. Based on the qualitative evaluation of the local habitat, this basic

00642622-Final 41 of7l 7/16/2004



requirement is unlikely to exist for large areas of OU-3 In addition a data gap was identified inthe SLERA and this will be addressed in the form of species surveys. The planned speciessurveys will address this issue and show whether there are any receptor species that find OU-3attractive enough to establish residence or use as a foraging area. Furthermore, the recent airmonitoring program provided conclusive evidence that there are no "fugitive air emissions" andtherefore they were not included in the USEPA approved Phase I CSM Report as a potentialexposure pathway for wildlife.

COMMENT 81:

The maintained grounds adjacent to open areas outside of OU-3 might provide a source ofexposure to local wildlife who occasionally forage at OU-3. The south landfill is an ideal openhabitat for hawks to forage. The risks need to be fully characterized to determine if additionalremedies are warranted for this OU.

Response 81:

While the open areas "outside of OU-3"might provide quality habitat, the presence of these areas,along with the characteristics of the majority of OU-3 makes it unlikely to be attractive topredators or prey species. This is because the Facility area is largely occupied by buildings,parking lots, and other active sites and impervious surfaces. There is no functional ecosystemwithin OU-3 based on direct observation of habitat characteristics. Furthermore, the Facility isfenced off potentially restricting terrestrial wildlife access to OU-3. The planned species surveyspresented in the FSP for OU-3 will directly address the potential for hawks to forage on the SouthLandfill.

COMMENT 82:

The EPA 2000 Amended Guidance on Ecological Risk Assessment at Military Bases: ProcessConsiderations, Timing of Activities, and Inclusion of Stakeholders does not apply in the case of aprivate facility. The Region 4 supplemental guidance is found at:www.epa.gov/region4/waste/ots/ecolbul.htm. This comment also applies to the work plan's maintext.

Response 82:

The amended 2000 guidance document is a refinement of the original 1997 guidance. ,sPresumably, it is an improvement over the earlier document as it incorporates hands-on f^\ Iexperiences with real life projects by the USEPA staff. There is no disclaimer that it is not » * , r \ rapplicable to private facilities. It is unclear why the 2000 guidance would not be applicable to allsuperfund assessments irrespective of property designations, as all ecological receptors should beafforded similar protection regardless of property ownership. The provided link refers to the2001 additions, which mainly contain screening values for soil which were used in the SLERA.

COMMENT 83:

Based on the tables and the discussion in the text, the SLERA used as a starting point a number ofpreliminary Chemicals of Potential Concern (COPCs) that were established during the

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RFI/CMS. Except chlorobenzene, all of these chemicals were carried through as pCOPCs in theSLERA. The Superfund risk assessment differs from RCRA in that a Superfund investigation willcharacterize all chemicals in the medium that received a release of contamination. EPAcustomarily requires a subset of full scans. Full scan analytes are screened in the SLERA. Hereonly the chemicals that were known to be related to the site were screened. The data werecollected as part of RFI/CMS activities and may not have included full analyte scans. If this is so,it should be identified as an uncertainty or data gap with a recommendation to the work plan foradditional data sampling. Chemicals that were not previously addressed will be included in theBaseline Ecological Risk Assessment. Three full scan samples plus 2,3,7,8-dioxin/furancongeners were proposed in OU-3, locations to be determined.

Response 83:

Indeed, the list of pCOPCs has already been approved by ADEM and the USEPA in the On-SiteRFI/CS Work Plan (Colder, 1998) on April 21, 1998 in the Off-Site RFI Work Plan (BBL, 1999)approved by ADEM and the USEPA on August 5, 1999, and in the Phase I CSM Reportapproved by the USEPA on March 5, 2004. Given the extensive thought, consultations with the /flrUSEPA, and work that went into the current selection, further discussions on this topic would Sseem unproductive because all substances that may be of concern have already have beenidentified. The issues raised in this comment will be addressed in the SLERA as potentialsources of uncertainty.

COMMENT 84:

The argument for not evaluating ground water as an exposure medium would be strengthened byincluding a discussion of whether ground water from the site may possibly discharge to surfacewater. Per discussion on April 13 the potential for ground water impacts to surface water was tobe addressed in the SLERA. Any data to support conclusions including dilution calculations,where appropriate, should be provided.

Response 84:

Data to support conclusions including dilutions calculations, where appropriate, have beendiscussed in response to Comment Nos. 73.

COMMENT 85:

The highest concentration of total PCBs, 16,620 J mg/kg, was taken at sample location SSR-18.This location was from the industrial area and appears to be paved in the immediate vicinity.SSR-18 is located adjacent to a grassy area, the site of the former chemistry laboratory. Therewere no samples proposed for the grassy area, the site of the former chemistry laboratory.Samples are needed in this area, since it is unpaved and may provide exposure to humans andwildlife. It is recommended that a dioxin/furan sample be taken here because the chemistrylaboratory apparently burned materials.

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Response 85:

Soil sampling will be performed at the site of the former chemistry laboratory. The samplelocations presented in the OU-3 FSP will be revised based on this comment and response toComment No. 5 on the OU-3 FSP. All soil samples will be collected and analyzed for PCBs.Once PCB results are obtained, three samples representing a low, medium, and high PCBconcentration will be collected and analyzed for an expanded list of parameters including dioxins.

Information included in the RCRA Facility Investigation Report indicates that waste materialfrom the Facility's laboratories were either hauled off site or placed in the Facility's landfills. Noreference to the laboratories burning materials was located. Consequently, the locations forcollecting samples to evaluate the expanded list of parameters will still be based on the measuredPCB concentrations.

COMMENT 86:

No samples were proposed in the OU-3 Field Sampling Plan for the "open area " shown onFigure 1 in Appendix F. Presumably this is the employee park. The park will be part of thehabitat survey. If this open area is considered to provide a habitat for ecological receptors, soildata are needed.

Response 86:

J*-No soil samples were proposed for the "open area" shown on Figure 1 in Appendix F since this fV>area has already been covered with a geotextile and a minimum of 14 inches of clean cover soil. ^This area was addressed as part of the East Side Cover project completed in 1997 and 1998. The yJ J\work performed is described in the Interim Measures Work Plan for Monsanto's Anniston Jl'S iFacility dated June 1997. Therefore, soil data will not be collected for the clean cover soils Splaced in this area. .^

COMMENT 87:

There were 15 samples of metals, mainly located in the industrial area proper. In general, thehighest levels of metals were collocated with the highest concentrations of total PCBs, e.g., SSR-07 and SSR-09. Because of the association with waste-generating processes at the site,additional characterization for metals is recommended in the maintained grounds and at thelandfills. Existing soils data for the landfills is scanty for metals. Recommend additionalsampling of landfills.

Response 87:

As discussed in Section 3.5.3.1, three sample locations will be selected from the Facility area(excluding the landfills) representing high, medium, and low PCB concentrations. Samples fromthese locations will be analyzed for PCB congeners, dioxins, and Target Compound List andTarget Analyte List parameters. This will provide additional characterization data for metalswithin the active plant area. This is consistent with the approach proposed by the USEPA in itsletter about congeners attached with this response to comments. USEPA requested that PCBcongeners, dioxins, and TCL and TAL parameters be analyzed at three locations in soil.

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Interim remedial measures have been constructed to prevent transport of affected soils from theSouth and West End landfills. As described in the RI/FS Work Plan, two cells of the SouthLandfill used for disposal of hazardous waste were closed with a RCRA-compliant cap in 1989,while the remaining cells in the South Landfill were covered with clay and a vegetative layer.The cap on a portion of the South Landfill was upgraded in 1998. The upgrade consisted of amultimedia cap with a high-density polyethylene (HDPE) liner, a drainage layer, and 14 inches ofsoil cover, and a vegetative layer placed over several closed cells and additional soil cover placedon adjacent areas. The West End Landfill was covered with a multimedia cap and a soil coverwas placed on the area immediately around the landfill. The cap included a minimum of 6 inchesof compacted clay, a HDPE liner, a drainage fabric, 18 inches of cover soils, and a vegetativelayer. -^

Sampling of the landfill is not proposed because sampling of the clean soil cover material >imported from off-Site sources would not be representative of natural surface types. This \includes the clean soil material placed over the impermeable covers that were previously I r !\constructed on the South and West End Landfills. J (j

COMMENT 88:

A map was provided showing the landfill cover. PCB concentrations in samples taken fromcovered areas were discussed. This information, however, did not address EPA 's concern thatcontaminants other than PCBs might be of concern on the landfills.

Response 88:

As discussed in response to Comment 87 sampling of the landfill is not proposed becausesampling of the clean soil cover material imported from off-Site sources would not berepresentative of natural surface types. This includes the clean soil material placed over theimpermeable covers that were previously constructed on the South and West End Landfills..

COMMENT 89:

Semivolatile organic compounds were collected only at the 15 stations where the metals datawere taken. Semivolatile organic compounds were undetected with high detection limits in everysample. High detection limits also limited the usefulness of the RFI/CMS data for pesticides,pentachlorophenol, o,o,o-triethylphosphorothioate, and Sulfotepp. Some of these chemicals aredifficult to detect in soil and may require a high resolution method or specific instructions to thechemists to optimize the technique to detect specific compounds. This is a matter to be addressedin the DQOsfor the OU-3 Field Sampling Plan.

Response 89:

The Data Quality Objectives included the OU-3 FSP will be revised based on this comment andComment No. 5 of the OU-3 FSP. The seven steps of the DQO process are as follows:

• State the Problem - Define the problem, identify the planning team, and examine budgetand schedule;

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• Identify the Decision - State the decision; identify the study questions, and definealternative actions;

• Identify the Inputs to the Decision - identify the information needed for the decision(information sources, basis for Action Level, and sampling and analysis methods);

• Define the Boundaries of the Study - Specify sample characteristics, define spatial andtemporal limits, and define units of decision making;

• Develop a Decision Rule - Define statistical parameters, specify Action Levels, anddevelop the logic for action;

• Specify Tolerable Limits on Decision Errors - Set acceptable limits for decision errorrelative to consequences (health effects, and cost); and

• Optimize the Design for Obtaining Data - Select a resource-effective sampling andanalysis plan that meets the performance criteria.

Currently the DQO discussion presents the seven step DQO process and identifies which steps (1-3) within the process have already been completed during previous OU-3 investigations but doesnot give a complete description of each step. Although the methods are presented of how each ofthe remaining steps will be addressed, they are not presented in a concise manner that allows thereader to easily determine how the seven step DQO process is being addressed. Therefore, the ^jTsection discussing the DQO process will be reformatted so that it follows the seven step process i jj, /as presented above in order to allow the reader to easily understand how each of the seven steps is .^ ^\being addressed. pJjrft^^

103H ofCOMMENT 90: (j^\ ^

ISince the chemicals \that are listed as having no screening values were apparently associated withthe site, additional effort should be put into finding appropriate benchmarks or toxicityinformation for compounds in Table 4.

Response 90:

The compounds that lack screening values were not detected in measurable concentrations at theFacility. Moreover, those compounds are unlikely to be found off-site, because they lackenvironmental persistence. Persistence was one of the parameters considered in the developmentof the pCOPC list of off-site areas and was discussed in detail in the Phase I CSM Report. Theissue of pCOPC selection was previously noted in the Response to Comment 83.

COMMENT 91

This effort is a Steps J & 2 ecological risk assessment. The discussion of the potentially completeexposure pathways and habitat quality is part of Step 1. Step 3 is typically a larger effort. Itincludes background screening and comparison to other benchmarks than Region 4's whencompounds lack Region 4 benchmarks. Because these chemicals are preselected as being of

00642622-Final 46 of 71 7/16/2004



potential concern at this site, there might be little change in the conclusions if the documentincluded Step 3a, refinement of chemicals of potential concern. Step 3b is the problem

formulation, refinement of conceptual site model, assessment endpoints, and risk questions. Step3 should include a refinement to the conceptual site model based on the results of the habitatsurvey. Text should clarify that this is a Steps 1 & 2 ecological risk assessment.

Response 91:

OLCS** ,We will clarify the text indicating that the current effort encompasses only the Screening Level . J^ .portion of the Ecological Risk Assessment (i.e., steps 1 and 2). Furthermore, step 3a will be ^^"^ ^added to the SLERA after the completion of the species surveys. Consistent with USEPA u 'guidance that is an appropriate time to include a Scientific/Management Decision Point in the cdecision-making process.

COMMENT 92:

Recommend that interpretation of the SLERA be enhanced by including a discussion of whereelevated concentrations were detected relative to land cover and barriers to exposure. Perhapscertain portions of OU-3 deserve focus.

Response 92:

The Parties will revisit data to examine this issue and include the findings in the revised SLERAfor OU-3 after completion of the proposed species surveys.

COMMENT 93:

An uncertainties section is part of every risk assessment. Use this section to discuss uncertaintiesand data gaps.

Response 93:

The Parties will add an uncertainties section to the revised RI/FS Work Plan as well as theoriginal SLERAs for OU-1 through 3.

COMMENT 94:

Table 4

Results of Screening Level Ecological Assessment for OU-3. The maximum detectedconcentrations listed in Table 4 for arsenic, mercury and total PCBs did not include the J-flaggedresults when the J-flagged result was the maximum. J-qualified results are valid data to be usedin the risk assessment. J-flagged results for PCBs were substantially higher than the maximumvalues reported in the table. The 16,620 J mg/kg PCBs at SSR-18 should have been evaluated inthe risk assessment. This change will not affect the conclusions, since these chemicals werealready identified as pCOPCs. However, a discussion of potential risks associated withextremely elevated concentrations is warranted.

00642622-Final 47 of 7) 7/16/2004


Anniston PCB SiteUSEPA ED No. ALD000400123 and ALD004019048 ..

/^Response 94:

Although Table 4 did not list the J-flagged results, they were included in the SLERA. For totalPCBs only the unqualified value was used in the screening level assessment. Since theunqualified value screened through there was no impact on the conclusions of the SLERA. Adiscussion of the J-qualified PCB data (and any other extremely high analytical data) will beadded to the revised RI/FS Work Plan.

It is noted that the area where sample SSR-18 was collected has been rededicated with a concretecap.

COMMENT 95

Section 3.2.1

Should note that air monitoring study being performed. The study is not yet complete. Theresults of the study will be considered when available to determine if additional fieldinvestigations in OU3 are required.

Response 95:

A discussion of the air monitoring study submitted to the USEPA on July 14, 2004, including asummary of the findings of this investigation, will be added to the revised RI/FS Work Plan.

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Comments on OU-3 FSP:

COMMENT 1:

Some changes to the scope of the OU-3 RI/FS will be made as a result of comments to the WorkPlan. Those changes also need to be reflected in the OU-3 FSP.

Response 1:

The Parties will incorporate the changes made in the RI/FS Work Plan into the OU-3 FSP asappropriate.

COMMENT 2:

No soil samples were proposed for either of the landfills in the OU-3 Field Sampling Plan.

Response 2:

As discussed in response to Comment No. 87 concerning the RI/FS Work Plan, samplingof the landfill is not proposed because sampling of the clean soil cover material importedfrom off-Site sources would not be representative of natural surface types. As a result nochanges are proposed for the OU-3 FSP.

COMMENTS 3:

The description of the habitat survey methodology was vague and incomplete.

Response 3:

Additional text to describe the habitat survey methodology will be added to the revised OU-3 FSPand the revised SLERA.

COMMENT 4:

It is not quite clear in the OU-3 Field Sampling Plan (FSP) what method will be used to purgeand sample the monitor wells. Given the COPCs for this site, EPA 's low-flow method forpurging and sampling monitor wells should be specified and used at this site to minimize sampleturbidity.

Response 4:

Low-flow purging will be specified for well sampling. This change will be noted in the revisedRI/FS Work Plan, the OU-3 FSP, and the Site-Wide QAPP. Section 5.7.3 will be replaced withthe following paragraphs.

"Purging of the monitoring well is performed to evacuate water that has been stagnant in the welland may not be representative of the aquifer. Purging will be accomplished using a either a

00642622-Final 49of7l 7/16/2004



disposable pump system or dedicated bladder pump for some previously installed wells at a rateof between 65 to 100 milliliters per minute (mL/min) to ensure minimal drawdown within thewell.

Purging will continue until water-quality parameters (i.e., temperature, pH, conductivity, turbidityand dissolved oxygen) have stabilized in accordance with the USEPA's Standard OperatingProcedures for Low-Stress (Low Flow) / Minimal Drawdown Ground-Water Sample Collection.Water removed from the well during purging will be containerized in 55-gallon drums and will bedischarged to the on-Facility groundwater recovery system in accordance with State and Federalregulations. Detailed information concerning handling of investigative derived wastes ispresented in Section 8.1."

COMMENTS:

Data Quality Objective Process for Soil Sampling in OU-3

Discussion of any DQO in the OU-3 Field Sampling Plan is absent. Figure 4 shows a map of theextant and proposed surface soil sample locations. The text reads:

Soil sample results from the RFI and Supplemental RFI provide good coverage of suspectedcontaminant sources (AOCs, SWMUs, and WMAs) on the Facility.

This sentence and the map are the only basis for selecting the locations. What is meant by "goodcoverage?" The RI/FS work plan regarding OU-3 soils is similarly incomplete. The discussionof the DQO and proposed soil sampling for OU-3 occupies a single paragraph only, beginningon page 3-8.

Determining the number of sample locations in the OU-3 should be accomplished in 5 steps

1) Preparation of a variogram based on extant soil sampling2) Point Kriging and isoconcentration mapping3) Estimating uncertainty in the kriged values using the kriging standard deviation4) Choosing potential sample locations based on these uncertainty estimates5) Asking "what-if vis-a-vis uncertainty to determine the value of any proposed additionalsample collection

Tools for GeostatisticsThere are many software tools available for geostatistics. EPA has DOS-based software calledGEO-EAS and GEO-PACK. The University of Tennessee Research Corporation has a productcalled SADA, that is well known to EPA. Syracuse Research Corporation has in development apackage called GeoSEM. I have experience with both ARCVIEW and SURFER. All packagesexcept GeoSEM use classical geostatistics with kriging based on normal spatial statisticsobtained from the variogram. GeoSEM has the option of using sequential Gaussian simulation,essentially a spatial bootstrap. Undoubtedly, there are other soft\vare packages also available.The point here is not to choose or recommend particular software but to inform about the rangeof options.

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Number of Soil SamplesThere exist several methods for estimating the number of soil samples. Most preferable would bethe geostatistical method briefly outlined above. Geostatistics would provide the most usefulinformation and could be used at all stages of the RI/FS process. Alternatively, classicalstatistical methods or bootstrap methods could be used to estimate the number of soil samples.Figure 4 in the OU-3 work plan shows 9 proposed samples. Using a relatively simple statisticalanalysis, EPA estimates that 12 -14 samples would be sufficient. It would be preferable to usegeostatistics to determine regions of high uncertainty and obtain a sufficient number of samplesto reduce this uncertainty.

Response 5:

The plant site on the Facility, where additional soil sampling will be performed, can besubdivided into two distinct area types for sampling purposes: 1) production areas that includeSWMUs, AOCs, WMAs, etc. and 2) non-production areas. The significance of the two areatypes is that the probability of encountering higher concentrations of COPCs within soil is muchgreater in production areas than in non-production areas. Therefore, the concentration of COPCsin soil across the Site is not expected to be homogenous.

Initial sampling efforts conducted as part of the RFI/CS and supplemental RFI/CS investigationswere designed specifically to determine the concentrations of COPCs in soil at or adjacent tospecific production areas. The initial sampling plan provided in the OU-3 FSP was developed toprovide more uniform sampling coverage of the plant site, which required sampling many of thenon-production areas. The number of samples proposed for the investigation was based uponproviding more uniform coverage across the Site and providing adequate information that couldbe used for calculating an exposure point concentration for risk assessment purposes.

The following statistical analysis was performed to refine the number of samples that will becollected as part of the investigation. This analysis will be included in a revised Data QualityObjectives section that'will be re-written based upon this comment and the response to CommentNo. 89 from the RI/FS Work Plan.

Classical Statistical Method

The procedures for using classical statistical methods to define the number of soil samplesrequired for the characterization of OU-3 and to satisfy DQOs is outlined in USEPA Data QualityObjective guidance (USEPA, 2000). This procedure specifies that for a known mean, varianceand comparison criterion, a sample number can be calculated such that future statistics can becalculated with a known confidence and power. The following equation used to calculate thenumber of samples required is identified in the USEPA DQO guidance in Appendix A:

n = (Z,.8+Z,.B)V/?2

Where:8 = Confidence IntervalB= Powers2 = Variance (standard deviation)n = sample size

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Z = Z-statistic (area under normal curve)? = difference between the mean of the extant samples and the PRO

To apply this equation to OU-3, the PCB concentrations from existing soil samples collected aspart of the RFI/CS and supplemental RFI investigations were tabulated. Five of the 42 datapoints were excluded from the analysis because these data points were located outside of the plantsite boundaries. The arithmetic mean and variance (standard deviation) of the PCBconcentrations were calculated. A comparison value of 0.74 mg/kg was selected, whichrepresents the industrial action level for PCBs in soil (Region 9 PRO table).

The above equation assumes a normal population distribution. However, the PCB concentrationvs. Z-score graph was evaluated and it did not represent a normal population distribution.Therefore, the log of the PCB concentrations was used which resulted in a more accuraterepresentation of a normal distribution graph. The mean and standard deviation of the log valueswere then calculated and used in the above equation to determine the proposed sample size forOU-3.

When using the log values for the mean and standard deviation, the calculated sample size is12.6. However, the log graph still did not represent a true normal population distribution,consequently the sample size was increased by 15% as described by Pitman's AsymptoticRelative Efficiency Equation (Pitman, 2004) resulting in a calculated sample size of 14.

The additional samples required based on the statistical calculations presented above will belocated based upon providing more complete sampling coverage across the plant site and willinclude placement of sample(s) near the former chemistry laboratory. Although geostatisticalmethods are often used to determine sampling locations at contaminated waste sites, theheterogenic nature of the plant site due to the two distinct area types make it is more appropriateto select locations based on area types and locations of previous samples.

The complete statistical analyses along with the revised DQOs will be included in Section 2.3 ofthe revised OU-3 FSP.

COMMENT 6:

Section 2,5.4 Laboratory Data Reporting Packages. Page 13

The plan proposes obtaining Level II data packages for all the samples collected with Level IVdata packages to be collected for 5% of the samples. Note that the four -level definition of dataquality has been replaced with a two-level definition encompassing Screening data with definitiveconfirmation and Definitive data (EPA/540/G-93/07J; Data Quality Objective Process forSuperfund). The definition of screening data indicates that at least 10% of the screening data beconfirmed using analytical methods and QA/QC procedures and criteria associated withdefinitive data. In addition, the proposed screening data quality level should be confirmed withdata end users, particularly risk assessment personnel, to ensure that the collected data will besufficient for its intended purpose.

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Response 6:

It appears that there is some confusion in the comment regarding "data quality" and "datapackages". The four level system discussed in Section 2.5.4 refers specifically to the reportingpackages supplied by the laboratory. Although some limited screening data will be used to helpfocus the investigations, definitive data will be used for all delineation and decision makingpurposes.

COMMENT 7:

Section 3.1 identify Data Gaps, page 15, Second Paragraph

The text in this section mirrors that in the Work Plan, and consequently should be modified in thesame way that the Work Plan will be modified:

• The statement that the extent of soil contamination is known is not correct.• Additional deep residuum monitoring wells should be located down gradient of OW5D,

OWR-7D and a shallow residuum monitoring well should be located down gradient ofOWR-10.

The text in this paragraph should be modified to address the additional data gaps.

Response 7:

Sections 3.1 and 3.2 will be modified to reflect the changes made in the revised RI/FS Work Planin response to Comment Nos. 34, 36, 39 and 42.

COMMENTS:

Section 3.1.2.5

Expanded parameter List Sampling. More information supporting the selection of samplinglocations OW-16A, OW-08A and OW-9for the expanded list of PCB analyses should be included.Which wells represent the high, medium and low PCB concentrations? What were thoseconcentrations and when were the data collected?

Response 8:

These wells were selected based on their location along the same flow line as discussed inresponse to Comment No. 42. The following language will be added to the revised OU-3 FSPafter the fourth sentence of the first paragraph of Section 3.1.2.5:

"Wells OW-16A, OW-8A, and OW-9 represent the high, medium and low PCB concentrations,respectively. Monitoring wells OW-16A and OW-8A were both sampled during the most recentsemi-annual groundwater monitoring event (Spring 2004) and the samples had total PCBconcentrations of 100 ug/1 and 11 ug/1, respectively. Monitoring well OW-9 was last sampledduring the RFI/CS Investigation conducted in 1998 and PCBs were not detected."

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COMMENT 9:

Section 3.2.1 Soil Sampling, page 23, 2nd paragraph, last sentence

Surface soil samples should be collected from ground surface to a depth of six inches, not to adepth of one foot as stated.

Response 9:

The last sentence of the third paragraph in Section 3.2.1 of the revised RI/FS Work Plan will bemodified to read as follows:

"The surface soil samples will be collected from ground surface to six inches below grade, andthe subsurface..."

COMMENT10:

Section 3.2.2 Groundwater Sampling, page 23

The depth, and the rationale for the depth, of the temporary and permanent monitoring wellsshould be stated in the OU-3 FSP.

Response 10:

Shallow residuum monitoring wells are installed within the first water bearing zone to a depth ofno greater than 45 feet BGS. The screening interval is based on the lithology encountered duringdrilling, and the determination of the water bearing unit is the responsibility of the field geologistoverseeing the installation. The following sentence will be added after the first sentence inSection 3.2.2.1 and at the end of the first paragraph in Section 3.2.2.2:

"The monitoring wells will be installed within the first water bearing zone to a depth of no greaterthan 45 feet BGS. The screening interval will be based on the lithology encountered duringdrilling, and the determination of the water bearing unit will be the responsibility of the fieldgeologist overseeing the installation."

COMMENT 11:

Section 3.2.2.1 OW-21A Area, Page 24, 2nd paragraph

If the extent of contamination is determined to be down gradient of MW07, an additionalpermanent monitoring well should be installed at the limit of the extent for future monitoring ofthe migration of contamination. This same comment would apply to the approach for the Interiorand Northeast Perimeter, South Landfill and West End Landfill investigations.

Response 11:

The following sentence will be added at the end of the last paragraph of Sections 3.2.2.1 and 3.2.2of the revised OU-3 FSP:

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"Once the down gradient boundary is established, the final temporary monitoring well will beconverted into a permanent monitoring well."

COMMENT12:

Section 5.2

Vegetable oil should not be needed as a drilling lubricant using the hollow stem auger (USA)drilling method. It is a permissible lubricant for other drilling methods such as air rotary.

Response 12:

Although the flights for hollow stem augers do not screw together and do not require vegetableoil as a lubricant, threaded bolts are used to secure one section to another. Additionally, the rodsused for collecting split spoon samples are threaded. In the event that a lubricant is needed forthese or any other threaded materials, vegetable oil will be used.

COMMENT 13:

Section 5.3.2

According to the Environmental Investigations Standard Operating Procedures and QualityAssurance Manual (EISOPQAM), Nov 2001, if a cement or cement bentonite grout is used thenthe pellet seal must be hydratedfor 24 hours or a fine sand (30/60 or finer) seal should be placedover the pellet seal (See ASTM D5092). Pellets above the water table should hydrate for 24 hoursnot one hour.

Response 13:

Per section 6.4.4 of the November 2001 edition of the Environmental Investigations StandardOperating Procedures and Quality Assurance Manual (EISOPQAM), "Where neat cement groutsare to be used pellets will be allowed to cure for 8 hours, or the manufacturer's recommendedhydration time, whichever is greater. Where the water table is temporarily below the pellet seal,potable (or higher quality water) should be added repeatedly to hydrate the pellets prior togrouting." The RI/FS Work Plan will be revised to include these requirements.

COMMENT 14:

Section 5.3.5

What drilling fluids will be used? The drilling method is Hollow - Stem- Auger. If the wells areainstalled using Hollow - Stem- Auger drilling, there should be no drilling fluids. In addition,Marsh Funnel tests viscosity which does not directly convert to density.

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Response 14:

Requirement 2 in Section 5.3.5 refers to which drilling fluids will be removed from the OU-3FSP.

COMMENT 15:

Section 5.3.6

The filter pack should consist of silica sand (20/40) and not gravel. Gravel is inappropriate for a0.010 well screen.

Response 15:

The term gravel will be removed from the first paragraph of Section 5.3.6. The second paragraphwill be replaced with the following language:

"The filter pack will have a uniform, well-sorted grain size and uniformity coefficient compatiblewith the formation materials and the screen, as described in section 6.6.4 of the EISOPQAM,November 2001. The filter pack will not extend across more than one water-bearing unit. Thefilter pack will be placed by pouring the sand through the hollow stem augers as the augers arewithdrawn."

COMMENT 16:

Section 5.3.6

Filter pack may be placed by pouring into the hollow stem auger as the augers are removed.

Response 16:

As discussed in response to Comment No. 15, the filter pack will be placed by pouring the sandthrough the hollow stem augers as the augers are withdrawn.

COMMENT 17:

Section 5.3.6 Filter Pack Requirements, page 32

The introduction of any potable water during well drilling and installation is a concern becausethe levels of contamination are suspected to be low, and could be diluted by water introducedduring well construction. The use of water should be avoided if possible; however, if it is used thevolume of potable water used to place the filter pack should be measured and recorded. Thevolume of water removed from the well during well development should be at least as much aswas introduced during drilling.

Response 17:

As discussed in response to Comment No. 15, the filter pack will be placed by pouring the sand

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through the hollow auger stems as the augers are withdrawn. Thus, a tremie pipe will not be usedto place the filter pack; and the use of water to place the filter pack will not be necessary. Section5.3.6 of the RI/FS Work Plan will be revised accordingly.

COMMENT 18:

Section 5.3.7

It is stated that the bentonite seal will be two feet. It is stated that the seal will be three to fivefeet in Section 5.3.2. FSP should specify that 100 percent sodium bentonite pellets will be used.

Response 18:

The first paragraph of Section 5.3.7 will be revised as follows:

"The bentonite seal requirements that will be followed are listed below:1. the bentonite seal will consist of at least three to five feet of bentonite between the filter

pack and the casing grout;2. the bentonite will be hydrated before placement of casing grout; and3. only 100 percent sodium bentonite pellets will be used."

COMMENT 19:

Section 5.3.8

See previous comments on grout and pellet seal.

Response 19:

The RI/FS Work Plan will be revised as discussed in responses to Comments Nos. 13 and 18.

COMMENT 20:

Section 5.3.9

Vents should be above protective casing or the bottom of the casing should have a weep hole toprevent the casing filling with water.

Response 20:

The following sentence will be added following the third sentence in Section 5.3.9:

"A weep hole will be installed in the protective cover to prevent the casing filling with water."

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COMMENT 21:

Section 5.5

When developing the monitoring wells, the developer should attempt to obtain a turbidity readingof below 10 NTU. Ten well volumes may not be sufficient to obtain the desired turbidity levels.

Response 21:

The following language will replace the first and second paragraphs of Section 5.5 of the revisedOU-3 FSP:

"Monitoring wells will not be developed until at least 24 hours after the installation of the surfacepads or until at least 24 hours after grouting the annular space, if a surface pad is not installed.The monitoring wells will be developed using a combination of bailing and/or pumping toproduce representative formation water. Development will be accomplished using a standard sizepump with a surge block and/or a stainless steel or Teflon® bailer with nylon rope. Developmentwill be continued until representative water that is free of cuttings or other materials introducedduring well construction is obtained. Representative water is assumed to have been obtainedwhen the water is free of visible sediment and the pH, temperature, and specific conductivityhave stabilized to within + 0.1 standard units, + 0.5°C, and + 10 percent, respectively. Also, themeasured turbidity readings should be less than 10 Nephelometric Turbidity Units (NTUs) orshould have stabilized to within + 10 percent for values greater than 10 NTUs in accordance withUSEPA's Standard Operating Procedures for Low-Stress (Low Flow) / Minimal DrawdownGround-Water Sample Collection.

The minimum duration of well development will vary in accordance with the method used todevelop the well. For example, surging and pumping the well may provide a stable, sedimentfree sample within minutes; whereas, bailing the well may require several hours of continuouseffort to obtain a clear sample. Field personnel will determine appropriate development methodsbased on site-specific conditions observed during well construction. The methods of welldevelopment, duration, pH, temperature, turbidity, and specific conductivity readings will berecorded on the well development log by the field personnel."

COMMENT 22:

Section 5.5 Monitoring well development, page 33

The text should note that well development should not begin until at least 24 hours afterinstallation of the surface pad. If no pad is to be installed, well development should not beginuntil 24 hours after grouting of the annular space.

Response 22:

As discussed in response to Comment No. 21, the revised OU-3 FSP will reflect that monitoringwells will not be developed until at least 24 hours after the installation of the surface pads or untilat least 24 hours after grouting the annular space, if a surface pad is not installed.

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Responses to USEPA Comments on theRl/FS Work Plan, OU-3 FSP and OU-4 FSP


COMMENT 23:

Section 5.7.3 Purging Prior to Well Sampling. Page 36

The text indicates that bailers may be used for purging. If used, bailers must have Teflon®-coatedleaders, and nylon rope. They must be lowered and raised slowly to decease disturbance of thewater and loss of volatile organic compounds. In general, when selecting the device to be usedfor purging, the device that has the slowest water removal rate and produces the least stress on awell should be used. The text indicates that the formula shown can be used to calculate one wellvolume. However, the formula actually calculates the volume of water per foot of submergedcasing and screen (F, in the equation). This value would need to be multiplied by the height ofwater in the well in order to calculate well volume.

Response 23:

The EPA's low flow purging protocol will be used for sampling of monitoring wells; therefore,bailers will not be used for purging and the calculation shown to determine well volume will notbe required and will be removed from the OU-3 FSP. See Response No. 4 from the OU-3 FSPfor further details concerning purging methods.

COMMENT 24:

Section 5.7.4.4

Section 5.7.4.4 states that generally pre-preserved bottles will be provided by the laboratory. Thesamplers must check the metals samples to ensure if the proper pH level has been obtained.Additional nitric acid preservative should be added if necessary.

Response 24:

The following sentence will be added to the end of the first paragraph in Section 5.7.4.4 of therevised OU-3 FSP:

"Sample containers for metal analyses should be checked to ensure that the proper pH level hasbeen obtained and additional preservative should be added, if necessary."

COMMENT 25:

Section 5.8

Soil Sampling and Section 5.8.1 Surface Soil Sampling, page 40. Surface soil samples should becollected from a depth ofO to 6 inches.

Response 25:

The first sentence of the first paragraph in Section 5.8.1 of the revised RI/FS Work Plan will bemodified to read as follows:

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Anniston PCS SiteUSEPA ID No. ALD000400123 and ALD004019048

"Surface soil samples will be collected from the ground surface to a depth of six inches."

The second sentence of the third paragraph in Section 5.8.1 of the revised RI/FS Work Plan willbe modified to read as follows:

"Surface soil samples will be collected with a stainless steel spade, spoon and/or hand auger thatwill be advanced to a depth of six inches, and the soil..."

COMMENT 26:

Section 5.8.2

Depth Soil Sampling, page 41, third paragraph. If a DPT rig is used to acquire the subsurfacesoil samples, a Teflon® liner should be used (not vinyl acetate as stated in the text).

Response 26:

The word "vinyl acetate" in the third paragraph in Section 5.8.2 will be replaced with the word"Teflon®" in the revised OU-3 FSP.

COMMENT'27:

Table 9

Table 9 should be consistent with Appendix A of the EISOPQAM. The table should specify a pHof less than two for samples collected for volatile organic compound analyses using sodiumbisulfate (NaHSO4).

Response 27:

Table 9 in the revised OU-3 FSP will be modified to be consistent with Appendix A of theEISOPQAM. Language will be added to the table that specifies a pH of less than 2 will berequired for samples collected for volatile organic compounds analyses using sodium bisulfate.

COMMENT 28:

Section 5.10.2 Sampling Equipment

This section appears to be incomplete. The first list of decontamination steps should include arinse with 10 percent nitric acid and a rinse with analyte-free water prior to the solvent rinse,and final rinse with analyte-free water or allow to completely air dry. A final step is to wrap inclean plastic or aluminum foil. Stainless steel items would not get the nitric acid rinse. It isassumed that these items are to be cleaned prior to field mobilization. Items cleaned in the fielddo not require the nitric acid rinse. It is unclear what the second list of decontamination stepsrefers to.

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Response 28:

A formatting error caused the listed procedures to appear as two separate lists with the stepsreferred to above included on the second list. The formatting error will be corrected, and as aresult, the items referred to will be included with the decontamination steps in the revised OU-3FSP.

COMMENT 29:

Section 5.11 Surveying, Page 46

Will temporary wells be surveyed?

Response 29:

Yes, temporary wells will be surveyed. To provide clarification, the sixth sentence in the firstparagraph of Section 5.11 of the revised OU-3 FSP will be revised as follows:

"The elevation of all newly installed wells, temporary wells, and piezometers will be surveyed atthe water level measuring point (notch) on the riser pipe."

COMMENT30:

Section 7 Quality Assurance/Quality Control Samples, page 49

Check with laboratory to determine if a separate temperature blank will be required.

Response 30:

The laboratory sends a temperature blank bottle to the field in the sample coolers. When thesamples are returned to the laboratory, the water temperature in these bottles is measured using acalibrated thermometer. In the event that the temperature blank is not returned to the laboratory,then the laboratory uses a gun style infrared thermometer to check cooler temperature. Thisdevice measures the temperature of the sample bottle contents without the need to open thebottles and potentially compromise sample integrity.

COMMENT 31:

Table 3

Table 3 Precision, Accuracy, Representativeness, Comparability and Completeness Data forAqueous Samples. The table indicates afield and laboratory precision goal of "50%. Typically,the field duplicate precision goal for aqueous samples is "20%.

Response 31:

A ±20% precision goal for aqueous samples for laboratory duplicates is achievable. However,our experience indicates that stipulating a field duplicate precision goal of ±20% will result in an

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excessive amount of qualified data. Therefore, Table 3 in the revised OU-3 FSP will be modifiedto indicate a ±20% goal for laboratory precision and a ±35% goal for field data.

COMMENT 32:

Table 5

Table 5 Precision, Accuracy, Representativeness, Comparability and Completeness Data for SoilSamples. The table indicates afield and laboratory precision goal of "100%. Typically, the fieldduplicate precision goal for aqueous samples is "35%.

Response 32:

A ±35% precision goal for soil samples for laboratory duplicates is achievable. However, ourexperience indicates that stipulating a field duplicate precision goal of ±35% will result in anexcessive amount of qualified data. Therefore, Table 5 in the revised OU-3 FSP will be modifiedto indicate a ±35% goal for laboratory and a ±50% goal for field data.

COMMENT 33:

Table 7

Table 7 Target Compounds/Analytes of Interest. This table shows 2 columns, one listingReporting Limits in ug/L and the other listing Reporting Limits in ug/kg. For clarity, these shouldbe labeled as Reporting Limits for Aqueous and Solid Samples, respectively.

Response 33:

This change will be made to Table 7 in the revised OU-3 FSP.

COMMENT 34:

Table 7

Table 7 Target Compounds/Analytes of Interest. In general, the reporting limits listed on thistable are at or below those of the CLP Program Contract Required Quantitation Limits(OLM04.3) (CRQLs). One notable exception is the reporting limit for 4-Nitrophenol (PNP), acontaminant of concern at the site. The reporting limits for water and soil listed on Table 7 are50 ug/l and 1700 ug/kg respectively. The CLP CRQLs for water and soil (Note: these are CLP"Soil Low " limits) samples are 25 ug/l and 830 ug/kg - approximately half of the planned limitslisted on Table 7. The lower reporting limits should be obtained.

Response 34:

The laboratory MDL studies for both aqueous and solid matrices indicate that the statistical MDLfor PNP is at least 10 times below the reporting limits specified in their QA Manual.Consequently, the laboratory has agreed that they will use Project-specific PNP reporting limitsof 25 ug/L for aqueous matrix samples and 830 ug/kg for solid matrix samples. The appropriate

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changes will be made to Table 7 in the revised OU-3 FSP.

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Comments on OU-4 FSP:

COMMENT 1:

Consider adding a sampling station in Choccolocco Creek upstream of the confluence of SnowCreek. Apparently PCB concentrations were high in this area.

Response 1 :

The fish sampling locations in the plan were designed to reflect the range of exposure conditions,quality of aquatic habitat, the home range of the target fish species, and the ability of anglers toaccess the areas. Based on these factors, it does not appear appropriate to select a location at thistime that is further upstream than Station 44. During the development of the supplemental FSPfor OU-4, additional consideration will be given to the location, species, number and type of fishsamples that will be collected to support both the human health and ecological risk assessmentsfor OU-4. _

COMMENT 2:X.

Since one of the ultimate goals of the risk assessment will be to link the contamination-infish withconcentrations in contaminated sediment, describe the sediment data and locations of sedimentsampling that will be used along with the fish tissue data to develop the biota-to-sedimentaccumulation factors.

Response 2:

Fish samples and sediment data used to develop the site-specific Biota-Sediment AccumulationFactor will be described in detail in supplemental FSP for OU-4. At this time, the current FSP isfocused on fish sampling in Choccolocco Creek is a continuation of an ongoing monitoringprogram, and the data collected as part of this monitoring program will be supplemented in thefuture to address data gaps identified for human health and ecological risk assessments.

COMMENTS:

Section 1 Introduction

The last sentence in this paragraph states "Data collected under the FSP will be used to supportthe human health and ecological risk assessments conducted as part of the RI/FS process for OU-4 and ......... " The size and type offish collected appear to address only human health issues, notecological issues. If fish have been selected as an assessment endpoint for the ecological riskassessment, then forage fish would be preferable to larger fish, and whole-body samples wouldbe preferable to filets for addressing ecological concerns. If fish have been selected as anassessment endpoint, then the FSP should discuss what fish will be collected and how the datawill be used to address ecological issues.

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Response 3:

It is likely that for OU-4 fish will be an assessment endpoint, as well as one of the criticalmeasurement endpoints (i.e., as prey for piscivorous animals). The OU-4 FSP will besupplemented in the future to address data gaps identified for human health and ecological riskassessment.

COMMENT 4:

Section 2.L1 Step 1

Identify the Issue. The first objective of this monitoring program is to gather PCB concentrationdata for fish tissue, which can be used to support risk assessment activities. This step does notaddress ecological risk assessment.

Response 4:

The OU-4 FSP is a continuation of an ongoing fish monitoring program and was not intended tobe the final sampling plan for all risk assessment activities. This monitoring program will besupplemented in the future to address data gaps for the human health and ecological riskassessments.

COMMENTS:

Section 2.1.2 Step 2

Identify the Decision. This section states that "The primary decision to be supported by the FSPis: Do PCBs in the edible tissue of fish pose a health risk?" Since PCBs are lipophilic,evaluating the edible tissue (filet) offish samples does not address the risk to wildlife. Many wildanimals (e.g., birds, larger fish, mammals) consume whole fish, especially forage size fish. Soevaluating only filets will not accurately reflect the risk to wildlife. Also see comment on Section2.1.3 below.

Response 5:

As discussed in response to Comments No. 3 and 4 above, the OU-4 FSP will be supplemented inthe future to address data gaps for human health and ecological risk assessments.

COMMENT 6:

Section 2.1.3 Step 3

Identify the Data Needed for the Decision. The data needed to support the primary decisionlisted in Section 2.1.2 are concentrations of PCBs in fish tissue, specifically fish fillets with skinoff or on, depending on the species. The issue of the use of skin-on or skin-off filets is not clearlyaddressed in the Plan. In Section 2.1.3 it seems that the decision will be species-dependent. InSection 3.2, however, the statement is made that a standard skin-off fillet will be used, and followADEM filleting procedures. Skin-on fillets have been recommended for use in state fish

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contaminant monitoring programs by the US EPA (US EPA, 2000). This is particularlyimportant in the case ofPCB's, since they are highly bioaccumulative and lipophilic. A lot of thefatty tissues in which PCB's will accumulate will be located subcutaneously, dorsally, in the darkmuscle, lateral line and belly flap (US EPA, 999). Much of the fatty tissues in these locations willbe removed through the process of removing skin to produce a skin-off fillet. Additionally,sources of potentially high variability of PCB data from adult fillets is discussed at the end ofSection 2.1.3. Added to this list should be the process of removing the skin to produce a skin-offfillet. A knife removing skin from musculature is likely to travel through most or all of the fattytissues mentioned above. The amount of fat that may remain with the skin or with themusculature would be a function of depth of cut and could therefore be expected to be another,probably large, source of variability in the analyzed PCB content of skin-off fillets. Additionally,by addressing PCBs only in fish filets, the data identified in this section does not addressecological risk assessment concerns.

The last sentence in this section states: " the number of adult samples to be collected at eachlocation is a range of 10 to 14 to reduce variability associated with results. " The FSP shouldexplain whether these fish will be analyzed as individuals or a number of composites at eachlocation. The FSP should describe how the planned data collection is statistically valid foraddressing human health risk issues. Will the data collected meet ADPH requirements for use indevelopment of fish consumption advisories? Since this FSP addresses human health riskassessment, this document should be reviewed by a qualified human health risk assessor.

Response 6:

The RI/FS Work Plan will be clarified to reflect that the fish will be evaluated as skin-off fillets.This is consistent with both the state of Alabama guidelines and is appropriate for the purposes ofevaluating potential human health risks as identified in Step 2 of the DQO process.

In terms of the number of samples and type of data needed by the state of Alabama to evaluatefish consumption advisories, the procedures identified in the OU-4 FSP are consistent with thestate's procedures and the number of fish samples of 10 to 14 is typically equal to or greater thanthe number of fish that are collected by the state as they conduct their evaluation. The RI/FSWork Plan will be updated with additional text identifying the process that will be used todevelop the location, species, number and type of fish samples that will be collected to supportthe human health and ecological risk assessments for OU-4, as further discussed below inresponse to Comment No. 9.

It is noted that the OU-4 FSP has been reviewed by Dr. John Schell.

COMMENT 7:

Section 4.2 Handling, Packaging, and Shipping Requirements

Affixing sample labels to containers (plastic bags) with clear packing tape may not work well,especially if materials have gotten wet from condensation, or as materials freeze and thaw. Amethod we have found to work well involves securing the tag to the sealed end of a bag with aplastic tie strap. Another secure method might be to leave the tag loose between the foil and theplastic bag for each fish sample. It may be best to top up coolers offish with additional ice,

00642622-Final 66 of 71 7/16/2004



rather than cushioning material, especially if there is any concern for fish attaining andremaining at an adequately cold temperature during shipment.

Response 7:

The OU-4 FSP will be updated to reflect the placement of a second tag between the foil and theplastic bag in the event the one taped to the outside becomes dislodged. Our preference is to usecushioning materials due the potential for shifting within the cooler as the ice begins to melt.

COMMENTS:

Table 2: Sample Containers, Preservation, and Holding Times

Not aware of a protocol that allows 14 days holding time for unfrozen tissue samples. Followingcollection, fish should be placed on wet ice, but separated from direct contact with the ice byeither wrapping in foil and placing in clean plastic bags, or by placing directly into clean plasticbags (if metals analysis only) and placing in clean coolers prior to processing. Fish should thenbe processed and frozen based on one of the following suggested guidelines:

• Fish should be processed (e.g., weighed, scaled or skinned if appropriate, and fileted)within 24 hours and then frozen prior to homogenization. These and additional guidelines aredescribed in "Fish Field and Laboratory Methods for Evaluating the Biological Integrity ofSurface Waters " (US EPA 1993).

Or:

• "Whole fish should be shipped or brought to the sample processing laboratory from thefield on wet or blue ice within 24 hours of sample collection. Fillets should be resected within 48hours of sample collection. " These guidelines described in "Guidance for Assessing ChemicalContaminant Data for Use in Fish Advisories, Volume 1, Fish Sampling and Analysis, ThirdEdition. Section 7. (EPA 2000).

The list offish (species and numbers) for collection at each sampling location may be difficult toactually obtain. Table 2 specifies cooling to 4 degrees C and laboratory freezing. EPA guidance(2000) specifies freezing to at or below -20 degrees C.

Overall, language regarding data collection for the ecological risk assessment should beremoved. The document does not contain any information to support ecological risk sampling.An ecological risk work plan (step 4), that provides the rationale for ecological sampling, shouldbe submitted separately, after all preceding ecological risk assessment steps (steps 1-3) havebeen completed and approved.

Where appropriate, EPA 's Guidance for Assessing Chemical Contaminant Data for Use in FishAdvisories (November, 2000) should be referenced for fish sample collection and processing.

Although ADEM's SOPs recommend skin-off fillets, the use of skin-on fillets for scaled fish wouldrepresent a worse case scenario. Otherwise, a defensible rationale should be presented for use ofskin-offfillets.

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Response 8:

Consistent with the USEPA's Guidance for Assessing Chemical Contaminant Data for Use inFish Advisories (USEPA, November 2000) the OU-4 FSP will be revised to reflect that fishsamples which are frozen will be maintained at or below -20° C. The OU-4 FSP will also beupdated to reflect that fish will be processed within 24 hours of collection consistent withguidance provided in "Fish Field and Laboratory Methods for Evaluating the Biological Integrityof Surface Waters" (USEPA 1993).

It is noted that these data can be used in combination with literature values for whole body tofillet ratios to assess potential ecological risks. The use of skin-off fillets will be maintained to beconsistent with state guidelines and to provide realistic data for risk assessment purposes.

COMMENT 9:

Data Quality Objectives Process for Fish Sampling in OU-4

The DQO discussion in the OU-4 sampling plan was generic and incomplete.

Bootstrapping the number offish samplesOne way to estimate the number of fish samples needed would be to craft a bootstrap todetermine the extent of uncertainty reduction for additional fish tissue samples at particularlocations. Information about angling success for various species, angler species consumptionpreferences and angler preferred fishing locations should be included in the bootstrap.

For example, if an angler fishes exclusively at station 44, the confluence ofColdwater Creek andChoccolocco Creek, then how many samples of which species would be needed to determine witha chosen degree of certainty whether the EPC for this angler was above or below a given risklevel. With this method, one could also specify the confidence level that the EPC was above orbelow this risk level.

Response 9:

This section of the OU-4 FSP will be revised to clarify that the "primary purposes of the samplingproposed in the FSP include the continued evaluation of temporal trends, an assessment of fishtissue PCB concentrations relative to the state of Alabama fish advisory level of 2 mg/kg in skin-off fillets, and to provide data for use in conducting the human health risk and ecological riskassessments for OU-4." Text will also be added to this section of the OU-4 FSP indicating "thatan evaluation of data gaps for fish will be conducted during the development of the SupplementalOU-4 FSP that will consider locations, species, type, and the number of samples needed tocomplete the human health and ecological risk assessments." This evaluation of data gaps willconsider the large body offish data collected by the Parties and the state of Alabama over the past15 years as well as the need to collect other data that may be needed to support a probabilistic riskassessment such as angler preferences.

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References

Alabama Department of Environmental Protection (ADEM). 2001. Hazardous Waste FacilityPermit. RCRA Post-Closure Permit for WMA I (Closed Hazardous Waste Landfill Cells) andWMA II (Closed Surface Impoundment). Solutia Inc. ALD 004 019 048. Issued January 7, 1997.Modified November 13, 1997 and May 3, 2001.

Agency for Toxic Substances and Disease Registry (ATSDR). Draft Health Consultation:Anniston PCB Air Sampling. January 2003.

A.T. Kearney, Inc., 1991. "RCRA Facility Assessment," August 1991.

Blasland, Bouck & Lee, Inc. (BBL). 1999. Supplemental RCRA Facility Investigation Work Planfor the Off-Site Portion of the RRI/CS Program. February 1999.

BBL. 2000. Off-Site RCRA Facility Investigation (RFI) Report, June 2000.

BBL. 2000. Phase II Off-Site (Floodplain) RFI/CS Investigation Work Plan, April 2000.

BBL. 2003. Phase I Conceptual Site Model (CSM) Report for the Anniston PCB Site. May 2003.

BBL. 2004. Field Sampling and Analysis Plan (FSP) for OU-2. April 2004.

BBL. 2004. RI/FS Work Plan. April 2004.

BBL. 2004. Operable Unit 4 Field Sampling Plan for the Anniston PCB Site. April 2004.

BBL. 2004. Site-Wide Quality Assurance Project Plan. April 2004.

BBL. 2004. Site-Wide Health and Safety Plan. April 2004.

Colder Associates Inc. (Colder). 1995. Detailed Design Report for the West End Landfill CoverRevisions.

Colder. 1998. RFI/CS Work Plan for the Anniston, Alabama Facility, 1998.

Colder. 1999. On-Site RFI/CS Draft Report for the Anniston, Alabama Facility, January 1999.

Colder. 2002. RFI/CS Report for the Anniston, Alabama Facility, October 2002.

Colder. 2002. Supplemental RFI/CS Work Plan for Solutia Inc., Anniston Facility, August 2002.

Colder. 2002. Revised Interim Measures Plan for Solutia Inc., September 2002.

ICF Kaiser Engineers, Inc. 1998. Final Report for the Detention, Cap, and Cover Project theSolutia Anniston Facility, June 5, 1998.

Monsanto Company. 1996. Correspondence to USEPA Providing Comments to RFA, February 1,1996.

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Monsanto Company. 1996. RCRA Part B Post-Closure Permit Application for Anniston,Alabama, April 1996.

Roux Associates, Inc. 1998. Dredge Spoil Area Evaluation Report, Snow Creek andChoccolocco Creek, Calhoun and Talladega Counties, Alabama.

Roux. 1999. Dredge Spoil Area RFI/CS Phase I Report, Snow and Choccolocco Creeks, Calhounand Talladega Counties, Alabama, September 13, 1999.

Roux. 2001. Removal Response Action Work Plan, llth Street Ditch, Anniston PCB Site,Anniston, Alabama, July 9, 2001.

Roux. 2002. RCRA Facility Investigation Results and Interim Measures Plan, Oxford LakeSoftball Complex, West Area, February 6, 2002.

Roux. 2002. Northside Cover Extension Interim Measures Report, Solutia Inc. Facility, AnnistonAlabama, July 8, 2002

Roux. 2002. Parking Lot Multi-Layer Cover Interim measures Report, Oxford Lake SoftballComplex, Anniston, Alabama, September 18, 2002

Roux. 2002. MMC Warehouse Interim Measures Report, Solutia Inc. Facility, Anniston,Alabama, September 6, 2002

Roux. 2003. Tennis Court and Parking Area Interim Measures Report, Oxford Lake SoftballComplex, Anniston, Alabama, May 28, 2003

Roux. 2004. Northside Cover Extension Interim Measures Report, Solutia Inc. Facility, AnnistonAlabama, April 21, 2004

Roux. 2004. Oxford Lake Softball Complex Interim Measures Report, Solutia Inc. Facility,Anniston, Alabama, May 25, 2004

Solutia. 2000. Interim Measures Work Plan for Extension of North Side Cover, Solutia Inc.Facility, Anniston, Alabama, January 24, 2000.

Solutia. 2000. Off-Site QML Soil Characterization and Remediation Plan, July 27, 2000.

Solutia. 2000. Corrective Measures Implementation Plan for Highway 21 Bridge, Revision 1,June 29, 200

Solutia. 2001. Interim Measures Work Plan, MCC Warehouse, Solutia Anniston Facility, May 17,2001.

Solutia. 2001. Quintard Mall Expansion Supplemental Off-Site Soil Report, November 2, 2001.

Solutia. 2001. Removal Action Work Plan for the Stockpiled Soil at the Oxford Lake SoftballComplex, April 24, 2001.

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Solutia. 2002. Correspondence to USEPA titled Design and Implementation Schedule for llthStreet Ditch Response Action, Anniston PCB Site, Anniston, Alabama, April 15, 2002.

Solutia. 2002. Corrective Measures Study for Excavated Soil Stockpile at Choccolocco CreekWaste Water Treatment Plant, Oxford, Alabama, February 22, 2002.

Solutia. 2003. NTC Removal Action Engineering Evaluation and Cost Analysis (EE/CA) Reportfor the Anniston PCB Site, Rev. 1.0, Anniston Alabama.

Solutia. 2003. Corrective Measures Implementation Work Plan for Excavated Soil Stockpile atChoccolocco Creek Wastewater Treatment Plant, Anniston, Alabama. January 2003.

URS Corporation. 2001. Soil Sampling Work Plan, The Anniston Wastewater Treatment Plant,April 2001.

URS Corporation. 2001. Interim Measures Plan, Anniston Water Works and Sewer Board,Choccolocco Creek WWTP Additions and Improvements, Oxford, Alabama, October 2001.

USEPA. 1988. Guidance for Conducting Remedial Investigations and Feasibility Studies underCERCLA. EPA/540/G-89/004. Office of Emergency and Remedial Response. October 1988.

USEPA. 1989. Risk Assessment Guidance for Superfund, Volume 1, Human Health EvaluationManual, Part A, Interim Final. EPA/540/1-89/002. Office of Emergency and Remedial Response.December 1989.

USEPA. 1994a. Guidance for the Data Quality Objective Process. EPA QA/G-4. EPA/600/R-96/055. August 2000.

USEPA. 1994b. RCRA Corrective Action Plan. OSWER Directive 9902.3-2A. May 1994.

USEPA. 2000. Amended Guidance on Ecological Risk Assessment at Military Bases: ProcessConsiderations, Timing of Activities, and Inclusion of Stakeholders.

USEPA 2000. Amended guidance on ecological risk assessment at military bases: processconsiderations, timing of activities, and inclusion of stakeholders. Memorandum from Ted W.Simon, USEPA Region. USEPA Region 4, Atlanta, Georgia.

USEPA. 2002. Region 4 Supplement Guidance to RAGS: Human Health Risk AssessmentBulletins, http://www.epa.gov/region4/waste/ots/healtbul.htm

USEPA. 2002b. Principles for Managing Contaminated Sediment Risks at Hazardous WasteSites. OSWER Directive 9285.6-08. Office of Solid Waste and Emergency Response. February12,2002.

USEPA. 2003. Letter from Ms. Pamela Langston-Scully to Mr. Craig Branchfield regardingcongener analyses dated March 13, 2003

00642622-Final 71 of 71 7/16/2004

Table A

BBLBLASLAND, BOUCK & LEE. INC.engineers, scientists, economists

I

July 2004Table A

Summary of Waste Disposal for All Operable Units

RI/FS Response to Comments

;-;;?:';Si;pperable Uriitii PI

OU-1

OU-2

11th Street Ditch

East Side Cover

NorthsideProperties

Oxford Lake Park

Quintard MallExpansion

ll blescHptiolhliiiiSoil removed from

residential properties aspart of Removal Order

and NIC RemovalAction

Sediments removedfrom 11th Street Ditch

and Snow Creek

Soils

Soils

Soils excavated fromsoftball fields

Soil excavated fromhillside in eastern part of

property

Topsoil excavatednorthest corner of

property

Topsoil excavated within100-yrfloodplain

^"^ i ""^:L"»:'::-'i ''-t 7--'" I™?fy/' ^i Quantity Excavated/Removed?

Approximately 4,900 cy

1 ,000 tons of sediments

N/A

N/A

Approximately 7,800 cy

Unknown

4,000 to 5,000 cy

3,000 to 4,000 cy

Disposal LocationT

Emelle Facility, ThreeComers Landfill,

Central Staging andSoil Management Area

Chem WasteManagement's Landfill

Covered in Place

Covered in Place

Capped in-place underparking lot; greater

than 10 ppm hauled toThree Corners Landfill

and Emelle Facility

Offsite (no writtenrecords); residentialproperties at variousquantities and 16,000cy to Meadow Lakes

Subdivision fromnewspaper solicitation

and investigation

•:j ibateiU;

On-going

1986-1987

1998

1999

2002

2000

2000

2000

••- Reference;;;'

EE/CA Report

RFA

Interim MeasuresWork Plan

RFI Work PlanAddendumNorthsideProperties

Interim MeasuresWork Plan for

Softball Fields atOxford Lake

Softball Complex

Quintard MallExpansion Off-

SiteCharacterizationReport includingSupplemental

Report

Page 1 of 4

July 2004Table A



' "' ~ bperableAUnr^ ifel

OU-2

OU-3



Remedial Action

ChoccoloccoCreek WastewaterTreatment Facility

Waste Generatedat Facility

k1^ i--Descripti6n| "i

Soils

Various residentialproperties

Soil excavated forexpansion of wastewater

treatment plant

Process WastewaterBiological Sludges

Biological Sludges

General Refuse, ProductContaminated Waste,Construction Debris

Acetone Still Bottoms

Sulfur Wastes

||||iii ilS r" ' :fe:j;Quantity Excavated/Removed ;

N/A

Unknown

60,000 cy soil

UnknownUnknown

Unknown

Unknown

ave discharge 20 gpm

Unknown

» Disposal Location-

Covered in Place

Landfill in GA

On-Site at thewastewater treatmentfacility under a multi-

media cover to beconstructed

WWTF (SWMU-29)On-siteLF(SWMU-l)

Local Sanitary Landfill

On-siteLF(SWMU-l),Phosphate LF (SWMU-

6), Trash Incinerator(SWMU-19)

WWTF (SWMU-29)

Sulfur Incinerator(SWMU 20) prior to

1973/1974, On-siteLF(SWMU-1) until late

1970s

; Date;: :v"

2000

2001

2001 and 2003

1961 to date1960 to 1983

1982 to 1986

1920 to 1991(present)

1961 to date

See disposallocation for

date

'. -f Reference -,,

N/A

Quintard MallExpansion Off-

SiteCharacterizationReport includingSupplemental

Report

ChoccoloccoCreek Corrective

MeasuresImplementation

Work Plan

RFARFA

RFA

RFA

RFA

RFA

Page 2 of 4

July 2004Table A



ri ir SOpei ieitirmilflSfe

OU-3

Waste Generatedat Facility

Old LimestoneBed (SWMU-8)

and Old LimestoneBed Storage Area

Closures

New LimestoneBed Storage Area

(SWMU-11A)Closure

New LimestoneBed(SWMU-11)

Closure

SWMU-7

liiMi e i ip:liph||S!iffi;!?;Spent Carbon

Spent LaboratorySolvents (SWMUs 16

and 14)

Spent Raney NickelCatalyst (SWMU 15)

Santotar and TherminolEnds

Surface Impoundmentand Storage Area

Excavated Soils

Liner Material

Molten Santotar

&i;SSS;K;::i;|>||igi||f tilfej;-'-'' 'v:::; '••.•••i.pr:":ifc;P*/.- '-:;--_.;•*•— fl:-afjTH •:•"»*• --..^_ .,-'-.. _• •,. ;Quantity Excavated/Removed

Unknown

8 drums of liquid every 3 months

20 55-gal drums per year

Unknown

N/A

19,500 Ibs contaminated soil

7,000 Ibs limestone; EPDM liner;3 ft soil below liner; 4,800 cy

clay/PNP/parathion mixUnknown Quantity of Santotar

Cooled and Landfilled

Disposal Location /;Offsite IncineratorLiquid haz waste

picked up by Rollins;Solid haz waste to

Emelle (Chem WasteManagement) on asneeded basis; Lab

waste disposed in On-siteLF(SWMU-l) prior

to 1989Offsite Metal

ReclaimerFormer Boiler (SWMU-

21), Present Boiler(SWMU-22), On-site

LF(SWMU-1)

Closed in place aslandfill

Unknown

On-site LF(SWMU-1)Cell 5E

SWMU 1

;•:!: -:;f;!j;.:r'- ;

.••rv;..Date.;::- • :-Unknown

See disposallocation for

date

Unknown

Unknown

1984-1985

1985

1998

1965 to 1989

h :!ReferehceVRFA

RFA

RFA

RFA

RFA

RFA

RFA

RFA/RFI WorkPlan

Page 3 of 4

July 2004Table A



v - -;-'. -. 5J.

-s-.;;l-^op

r\\ i iuu-o

OU-4

-j M&?jKJiliJjimerable UmtSSlp

SWMU-12

SWMU-31

SWMU-41

SWMU-42

SWMU-43

SWMU-46

AOC-C

Highway 21 BridgeProject

^^ igt gll sf .4

Excavated Materials

Oily Condensates

Process and DemolitionWastes

Process and DemolitionWastes

Production Wastes.Demolition Materials

Two Hold Tanks, FourAeration Basins, and

Two ClarifiersUnderground Storage

Tanks

Soils

:j p^-i';!-.rl;-:='il.rf.i]. j- |:-J!-v.:..'.:-L

iQUantity Excavated/Removed!

Unknown Quantity Excavated

Unknown

Unknown

Unknown

Unknown

N/A

Four Tanks of UnknownCapacity

NA

"^•'•' ~~», ,j. ~ • •

' Disposal Location

Cell 5E

Discharged to WWTP

SWMU 1

SWMU 1

SWMUs1,6, and 20.SWMU 1.

Landfilled in Place

Unknown

Covered in Place

- • • • • - • . . • • - • • •

. Date

Unknown

Unknown topresent

After 1986

1972

After 1988

1988

mid1980's

2004

' - . ' '-. -' '" :' ^

Reference -RFA/RFI Work

Plan

RFA

RFA

RFA

RFA

RFA

RFA

N/A

Page 4 of 4

Attachment A

BBLJBLASLAND, BOUCK & LEE, INC.engineers, scientists, economists

Attachment A

Data Request KH GW2004

Attachment A


fi; ~- '-SI 2; [4; SN^BfiiGliijQ l

OWNA16A'0.026NDND100NDNDNDNDND84ND12NDNDNDND100NDNDND

ND

NANAND12NDNDNDNDNDNANANANANANANANANANANANANA

OWNA190.087NDNDNDNDNDNDNDNDNDNDNDNDNDNDNDNDNDNDNDNDND

OWNA2VA0.042NDND1700NDND5700NDNDND150NDNDNDNDND30000NDNDNDNDND

QWNA21AFNANDNDNDNDNDNDNDNDNANANANANANANANANANANANANA

OWNA22ND

0.00041NDNDNDND0.6NDNDNDNDNDNDNDNDNDNDNDNDNDNDND

OWNA22SNA

0.00028NDNDNDNDNDNDNDNANANANANANANANANANANANANA

Attachment A


BBLBLASLAND, BOUCK & LEE, INC.engineers, scientists, economists

-Vi>.-?f.- g;—' I-5*

LETTER FROM CRAIG BRANCHFIELD, SOLUTIA TO PAMELA …

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