HAZARDOUSSIT I CONTROL

DIVISION

EPA Region 5 Records Ctr.

253058

CONTRACT NO.

RESPONSIVENESS SUMMARYFOR THE FEASIBILITY STUDY

CHEM-DYNE SITEHAMILTON, OHIO

WA21.5M10.0W65310.DO

JUNE 1985

CHJMBHILL

RESPONSIVENESS SUMMARYFOR THE FEASIBILITY STUDY

CHEM-DYNE SITEHAMILTON, OHIO

WA21.5M10.0W65310.DO

JUNE 1985

GLT267/57

CONTENTS

Chapter Page

1 INTRODUCTION 1-L

Purposfe of the Responsiveness SummaryBackground

2 FEASIBILITY STUDY OVERVIEW 2-1

Site Background InformationEndangennent Assessment SummaryRemedial Action Alternative Summary

3 PUBLIC COMMENTS - U.S. EPA RESPONSES 3-1

Remedial Investigation Report CommentsFeasibility Study Technical Analysis

SoilGroundwaterFord CanalOnsite Utilities

Remedial Actions - Public Recommendations

SoilGroundwaterFord CanalOnsite Utilities

Schedule for Remedial ActionImplementation

Site Risks - Present and FutureRemedial Contingency ActionsCosts Versus Remedial Action SelectionFeasibility Study Comment Period

Appendixes

A Oxford Audubon Society and HAPSO Comments andResponses on Cham-Dyne Final RI Report

B Oxford Audubon Society Comments and Responseson Chem-Dyne Feasibility Study

C U.S. EPA Newspaper Advertisements for December 3,1984, Public Hearing and Comment Period Extension

D Public Comments

GLT267/49

Chapter 1INTRODUCTION

PURPOSE OF THE RESPONSIVENESS SUMMARY

The U.S. Environmental Protection Agency (U.S. EPA) has eval-uated and selected remedial actions to control the chemicalwaste contamination of the Chem-Dyne site in Hamilton, Ohio.Remedial evaluations were presented in a Feasibility Studyissued in November 1984. A decision on the specific remedialactions to be taken has been made by the Agency and has beenincorporated in the Consent Decree entered into by the res-ponsible parties.

The purpose of this document is to report both verbal andwritten public comments received on the Agency's remedialaction evaluations in the Feasibility Study and to reportthe Agency's responses to public comments. Authority forthis work is from the Comprehensive Environmental Response,Compensation, and Liability Act (CERCLA) also known as"Superfund."

BACKGROUND

The Feasibility Study (FS) for Chem-Dyne was issued on Novem-ber 19, 1984. The FS was based upon numerous site investi-gations conducted in 1983 and reported in the Final RemedialInvestigation Report issued in May 1984. A public meetingon the FS was held on December 3, 1984, at the City Hall inHamilton, Ohio. Verbal comments on the FS were receivedduring the meeting. Written public comments were receivedby the U.S. EPA through Friday, December 28, 1984.

GLT267/54

1-1

Chapter 2FEASIBILITY STUDY OVERVIEW

This responsiveness summary is based on the Chem-Dyne Fea-sibility Study Report issued on November 19, 1984. Forbackground, major elements of the Feasibility Study are sum-marized in this chapter.

SITE BACKGROUND INFORMATION

SITE DESCRIPTION

The Chem-Dyne site is within the limits of the City of Hamil-ton, Butler County, Ohio, which had an estimated 1980 popu-lation of 66,400. The site covers approximately 20 acres onthe northern border of the city.

The site is bounded immediately on the south by a residentialdistrict. Farther to the south are the business districtand additional residential districts. It is bounded on theeast by a municipal park whose facilities include six ball-parks and a municipal swimming pool. Residential dwellingslie to the east of the park. The site is bounded on thenorth by the Ford Hydraulic Canal, which flows west to theGreat Miami River. Immediately north of the canal is anagricultural field. Approximately 1,500 feet north of thesite is one of Hamilton's two water treatment plants, whichpumps groundwater from deep wells during the summer months.The site is bordered on the west by a railroad right-of-way.Next to the railroad tracks is the Ransohoff Company, a sheetmetal fabrication plant. Also to the west is the City ofHamilton Power Plant. About 75 yards from the site are coalpiles I and a large petroleum storage tank for the power plant.Farther to the west are warehouses for Champion Paper and asmall residential area.

At th» start of initial surface cleanup remedial activitiesin xiay 1983, there were approximately 8,600 drums, 30 above-grade tancs, and 2 open-top, belowgrade tanks onsite. Thetan>s and drums contained an estimated 463,000 gallons offluid, 109,000 gallons of sludge, and 86,000 gallons of solids.

were generally in a badly deteriorated condition; manywere leaking or open.

Other onsite equipment included two tanker trucks (5,000 gal-lons) , four semitruck trailers, two flat beds, an empty fueltype tank (300 gallons), one outdoor reaction vessel (100 gal-lons)

o Chem-Dyne buildingo Boiler buildingo Ward Manufacturing buildingo Ford building (formerly a Ford tractor factory)o A blue warehouse (prefabricated)

Former operations by Chem-Dyne centered around the Chem-Dynebuilding. The building housed the Chem-Dyne offices, blend-ing tanks, and other equipment; it is presently in a dilapi-dated condition.

Three nearby buildings, the boiler. Ward Manufacturing, andFord building, are also dilapidated. There is no historicalevidence to indicate that they were used by the Cham DyneCorporation. A detailed inspection of the buildings in Octo-ber 1983 by CH2M HILL did, however, find occasional drumsand evidence of contamination in the basement of the boilerbuilding caused by seepage draining into the basement.

The blue warehouse and the parking lot to the south werepreviously used by the Chem-Dyne Corporation to store drums.The inspection conducted in October 1983 by CB2M HTLL foundsigns of drum storage in the building and on the parkinglot.

HISTORICAL PROPERTY OWNERSHIP

Information pertaining to property ownership was obtainedfrom a title search conducted for the U.S. EPA by LawyersTitle of Cincinnati, Inc.

The Chem Dyne site is situated on a reclaimed wetland. Theearliest found property records indicate that the wetlandarea was owned by the Miami Conservancy District (MCD) asearly as 1916. In 1917, the MCD leased the property to theHamilton and Rossville Hydraulic Company (HRH). HRH con-structed levees and operated at least two canals, a reservoir,and a power plant on the property until 1919.

In 1919, MCD sold portions of the property to the Ford MotorCompany and the HRH. In a joint effort by the three parties,the wetland area, reservoir, and west canal were filled andthe south canal was relocated to the north end of the presentsite. Material for the new levees was excavated from thenew channel area. The eastern portion of the site was usedas a spoil area for the north end channel improvements. Theremaining fill material for the site was excavated from theGreat Miami River.

Ford constructed a hydroelectric plant adjacent to the canaland operated a tractor plant at the site starting around1928. Operations at the plant lasted approximately 10 years.

2-2

Records indicate that in the early 1950's Bendix AviationCorporation acquired all of the stock of the HRH. In June1951, the Ford Motor Company sold its property to Bendix.Bendix conducted manufacturing operations at the site until1959.

In 1959, the former Ford site was split. The two tractspassed through several ownership arrangements including theChem-Dyne Corporation. A detailed summary of the propertyownership is reported in the Remedial Investigation Report,Volume 2, Task 1 Technical Memorandum.

Parts of the tracts of land described above are includedwithin the boundaries of the Chem-Dyne site because ofencroachment by Chem-Dyne operations onto these adjacentproperties.

The Ford Hydraulic Canal is not within the hazardous wastesite boundaries as defined in the FS. However, as a previousreceptor of direct stormwater runoff and discharges from theChem-Dyne site, this property is considered in the feasibilitystudy. Most of the canal was obtained by the HRH in the1919 agreement with the MCD. The HRH conveyed the propertyto the City of Hamilton in 1963.

HAZARDOUS WASTE SITE HISTORY

As early as 1974,. chemical wastes may have been trucked tothe Chem-Dyne site. In the fall of 1975, Kovacs and Whittenformed Spray-Dyne which made antifreeze by recycling chemicalwastes. In 1976, the operations were expanded and the Chem-Dyne Corporation was formed to collect and dispose of indus-trial chemical wastes. Some effort was made to recycle oilwastes as fuel. Wastes that were unsuitable for recyclingwere stored in drums and tanks on the site or shipped toother disposal sites.

The Chem-Dyne facility operated until February 1980. In5 years of operation, the facility accepted waste from nearly300 generators. The materials handled included pesticidesand pesticide residues, chlorinated hydrocarbons, solvents,waste oils, plastics and resins, PBB's, PCB's, TRIS,.acidsand caustics, heavy metal and some cyanide sludges, and pack-aged laboratory chemicals. More than 30,000 drums and300,000 gallons of bulk materials were onsite when theoperations were closed.

Operations of Chen-Dyne resulted in uncontrolled releases ofhazardous materials. Mixing of liquid wastes was often donein open pits releasing noxious vapors. Reportedly, 55-galIondrums were punctured with pickaxes and allowed to leak orwere dumped onto the ground or into a trough or pit.

2-3

Taak cars were reportedly emptied onto the ground, into troughsand sewers.

In its 5 years of operation, a number of environmental inci-dents were reported at the Chem-Dyne facility. From 1976 to1979, there were at least five fish kills in the Great MiamiRiver that were attributed to Chen-Dyne operations. Onefish kill stretched for nearly 37 miles from the FordHydraulic Canal to the mouth of the Great Miami River. In1976, a series of fires and a fuming railroad tank car inci-dent generated active public concern. Another series offires occurred in 1979.

LEGAL ACTIOHS

Legal actions involving the Chem-Dyne Corporation began inJune 1976 when Chem-Dyne filed a $30 million suit againstthe City of Hamilton and its officials for harassment. OnSeptember 29, 1976, the State of Ohio filed a suit againstNhltten, Kovacs, Chem-Dyne, et al. The suit alleged thatthe companies were responsible for killing more than amillion fish and water animals in the Great Miami River andfor emitting offensive odors into the air. The suit soughtpenal, compensatory, and punitive damages totalling $340,000and called for a permanent end to illegal discharges intoOhio waters and abatement of air pollution nuisances. Bothsuits were settled on July 19, 1979, when all parties agreedto a stipulation and judgment entry whereby (Them Dyne agreedto prevent future pollution and to remove all inventory within12 months. Chem-Dyne also agreed to drop its suit againstthe City of Hamilton and to pay $75,000 in fines.

The U.S. EPA filed suit against Chem-Dyne et al. under theprovisions of RCRA on Decenber 19, 1979. Two days later,the City of Hamilton and the Ransohoff Corporation joined inthe federal suit against Chem-Dyne. The suit sought to forceChem Dyne to stop operations, remove wastes from the site,and clean up any soil or groundwatar contamination. On Jan-uary 25, 1980, the District Court granted a preliminaryinjunction prohibiting the defendants from hauling, receiving,or taking delivery of any industrial wastes at its premises.

Also, as a result of noncompliance, on January 24, 1980, theOhio Attorney General filed a motion in the state courtsasking that a receiver be nimed to assume operations at Chem-Dyne. The state court appointed Jack Zettler, a Hamiltonlawyer and accountant, as receiver on February 4, 1980.

On August 26, 1982, the EPA reached agreement with over 100companies for surface cleanup of the site. The generatorsagreed to pay $2.4 million in cleanup costs. The agreementalso allowed the government to demand additional payments ifunexpected costs arose. Simultaneously, the U.S. Department

2-4

of Justice filed a suit to recover additional costs fromowners, operators, and major generators who refused to par-ticipate.

WASTE CLEANUP ACTIONS

The receivership, established February 4, 1980, was chargedwith the duty of carrying out the court's order to removeall waste from the site. With technical assistance from theOhio EPA, the receivership directed cleanup operations untilit had exhausted all Chem-Dyne money and assets in November1981. During receivership, about 20,000 drums were removed,mostly by generators who agreed to remove their wastes.Additional cleanup operations were financed by selling assetsof the company and by accepting and properly disposing ofsome industrial wastes.

In December 1981, the State of Ohio submitted Chem-Dyne asOhio's top priority Superfund project. In 1981, the sitewas included on the U.S. EPA's Interim Priority List as Ohio'shighest priority site.

Between March and April 1982, several remedial actions wereperformed at the Chem-Dyne site with Superfund money. Theseactions included fence repair, cleanup of the loading dockarea, waste removal from bulk tank No. 6, and plugging ofselected site storm drains.

From November 1981 until May 1983, voluntary removal of wasteby generators proceeded under the supervision of the OhioEPA.

From May until November 1983, a cleanup contract for theplanned removal of all remaining surface wastes from theChem-Dyne site was undertaken and managed by the U.S. ArmyCorps of Engineers as an initial remedial measure in accor-dance with the National Contingency Plan (NCP).

ENDANGERMENT ASSESSMENT SUMMARY

The endangerment assessment prepared for tha FeasibilityStudy examined the potential human health effects under the"no-action" alternatives for each "operable unit" or environ-mental media including soil, groundwater, surface water, andonsite facilities.

The endangerment assessment concluded that implementation ofthe no-action alternative for each operable unit could resultin the following outcomes:

2-5

SOIL

A potential excess lifetime cancer risk of 4 x 10 isassociated with ingestion of soil with the siteconcentrations. Population exposure associated with dustentrainment and direct soil contact increased this cancerrisk.

GROUBDMATER

The production of drinking water at the Hamilton well fieldis estimated to present an excess lifetime cancer risk of2 x 10 and 9 x 10 for Cases 1 and 2, i.e., existing plumemigration only and plume with leachate migration. The cancerrisks are estimated to be 1 x 10~ and 2 x 10 for the twocases at a hypothetical future well located 100 feet fromthe Chem Dyne site. The potential for dermal absorptionsand inhalation of released volatiles during household wateruse may increase this risk. Mean groundwater concentrationsfor volatiles are not projected to exceed the ACGIH thresholdlimit values at the Champion Paper production floor, and thedischarge of groundwater by Mercy Hospital is estimated toproduce contaminant concentrations in the Great Miami Riverthat are generally below freshwater aquatic life toxicityvalues identified by EPA in its ambient water quality criteriadocuments.

FORD CABAL

There is no known immediate health endangerment caused bycanal water or sediment.

OBSITB FACILITIgS

Potential health endangerment is caused by direct contactwith contaminants in several onsite facilities.

REMEDIAL ACTION ALTERHATIVE SOMMARY

The Feasibility Study followed a stepwise process to assess,screen, and evaluate remedial action technologies and alter-natives for problems identified at the Chem-Dyne site. Thegoals of the stepwise procedure were to reduce the range ofalternatives to the most suitable remedial actions and todocument the decision process.

Assessment of applicable remedial action technologies (FSChapter 3) was based on the following criteria: first, tech-nical feasibility; second, environmental, public health, andinstitutional effects; third, estimated present worth costs.Bernedial technologies were assessed by these criteria indepen-dently without consideration of possible advantages or dis-advantages of technologies when applied in combinations.

2-6

Following assessment of individual remedial technologies,"assembled" remedial action alternatives were screened usingthe same criteria as applied to the technologies (FS Chap-ter 4). An example of an assembled remedial alternative forgroundwater is the following: groundwater extraction withair stripping treatment and discharge to the Ford Canal. Inthis example, three technologies are combined or assembledinto a single alternative.

Finally, detailed analysis of selected assembled remedialaction alternatives (FS Chapter 6) was based on more detailedconsideration of the criteria applied to the remedial tech-nologies, particularly technical performance and estimatedpresent worth costs.

Detailed analysis yielded four example remedial action alter-natives that represent a reasonable range of response to theendangerment at Chem-Dyne according to the National Contin-gency Plan. To summarize the example remedial alternatives,four tables from the Feasibility Study are reproduced on thefollowing pages. These summary tables present only outlinedescriptions of the alternatives and the estimated costs.The no-action alternative was also carried through the Fea-sibility Study for reference. The no-action alternativemeans essentially "do nothing;" it is therefore not includedin the following tables.

GLT267/50

2-7

Table 1 (Page l of 2)(FS Table 6-1)

SUMIAKT 0? EXAMPLE ASSEMBLED ALTERNATIVE NO. 1 (AA-1)

Coat Estimates*

Renedial Action

Soil

Excavate a 10'-deep trench around thaperlMter and renova soil; backfillwith clay

o Excavation and Backfilling

Excavate and remove 2' of soil onand offsit* with 6' removal inAreas 9, 10, 11/12, and 13;

o Excavationo Transportationo Disposal

Demolish and remove asphaltparkins lot south of blua warehouse

o Demolition and Soil Excavationo Transportationo Disposal

Cap and seal entire site withmultilayer clay/membrane system

groundwsterExtraction wallsj groundwaterremoval till 10"6 cancer riskcriteria are set

Air stripping at 99 percenttotal VOC reaoval

Off-gee scrubbing by carbonadsorption

Facilities

Deaolish and rsaove all buildingsand structures

o Demolitiono Transportationo Disposal

Deeollsb and leeuve concreteslab and loading dock

o Detentiono Transportationo Disposal

Raeove two open top onelte burledtanks

Seal all connections tonorthwestern atom

Capital

AnnualOperation &Maintenance

PresentWorth

relinenorthwestern storm sewer

$80,000

1,800,0002,200,0002,900,000

260,000390,000520,000

1,900,000

130,000

1,500,000

1,800,000

980,000610,000770,000

76,000150,000190,000

1,000

10,000

15,000

$17,000

50,000

16,000

460,000

$80,000

1,800,0001,200,00011,900,000

260,000390,000520,000

2,100,000

390,000°

1,600,000°

3,600,000°

980,000610,000770,000

76,000150,000190,000

1,000

10,000

15,000

GLX267/51-1

2 of 2)

_*™*r^ bOpUAUOB • PrCMBt

Uorth

5,000

97,000

10,000

4.100.000

543,000 23,100,000

54,000 2,310,000

$5*7,000 $25,400,000

V

Table 2 (Pag* 1 of 2)(FS Table 6-2)

SBMMAMt OT EXAMPLE ASSEMBLED ALXBWUXIVE NO. 2 (AA-2)

Cost Estlaates'

Remedial Action

Soil

Excavate and remove 3' of soil;on and offsits;

o Excavationo Transportationo Disposal

Demolish and remove asphalt parkinglot south of blue warehouse

o Demolition and Soil Excavationo Transportationo Disposal

Cap and seel entire site withmultilayer clay/membrane system

Groundwater

Extraction wells; gronndwater removalto detection limits

Air stripping at 90 percent total VOCral

Off-gaa •crabbing by carbon adsorption

Facilities

Daaolisb and reaove all buildingsand •troctorw

o Demolitiono Transportationo Disposal

DesDlisb and reeove concrete•lab and loading dock

o Demolitiono Transportationo Dispossl

fleams tw> open top onsite burledtanks

Seel all connections to northwestern•ton

Dacontaadnate and reline nortiwestern•tor* sewer

seel with groatClean 8" siphon

Rehabilitate «

2 (?••* 2 of 2)

(at 10%)

Capital

3.400.000

17,000,000

1,700,000

$11,700,000

Can

Operation fc

320,000

32,000

$380,000

3.400.000

18,600,000

1,900,000

$20,500,000

Table 3 (Page 1 of 2)(TS Table 6-3)

SUMMARY OF EXAMPLE ASSEMBLED ALXERHAXIVE NO. 3 (AA-3)

Cost Estimates

Remedial Action

Soil

Excavate and remove 2" of soilon and off«ita;

o Excavationo Transportationo Disposal

Cap and seal araas of soil andconcrete slab removal with lornovar clay system

Remove aspbalt parking lot south ofblua warehouse) axcavata and rsmove2' of soil) backfill and repavesraplaca guardrails and catch basin

o Demolition and Excavationo Transportationo Disposalo Repaying *nd Backfillingo Replace goardraila and

catchbaains

Groundwater

Extraction walla j groundwater removaluntil 10 cancar risk criteria are Bet

Air stripping at 70 percent total HOCval

Off-gas scrubbing by carbon adsorption

Facilities

Demolish and remove Chev-Dyne, garageand boiler buildings; backfill and capand seal with loaa over clay

o Demolisho Transportationo Disposalo Backfill

DcBolian and rsams concrete coalblnj cap and seal with loaa over clay

o Deeoliaho Transportatioao Disposal

Dewlish andslab and loading

o Desnlisno Transportationo Disposal

Decontamiaata Ford, Hard andblue warehouse buildings

Reaove two open top oosite burledtanks

Seal all connections to northwesternstora sewer segaent

Decontaminate and rallna northwesternstorm sewer segment

Capital

$1,100,0001,300,0001,700,000

980,000

260,000390,000520,000110,000

10,000

130,000

130,000

620,000

180,000100,000170,00058,000

24,00045,00060,000

76,000150,000190,000

420,000

1,000

10,000

15,000

Annual hOperation & PresentMaintenance Worth

$1,100,0001,300,0001,700,000

$11,000 1,100,000

260,000390,000520,000

2,000 130,000

10,000

50,000 590,000°

1,000 130,000d

140,000 l,200,000d

180,000100,000170,00058,000

24,00045,00060,000

76,000150,000190,000

Tafcl* 3 tt««* 2 of 2)

(•CIA)

CtMt C*tiH*CM

Capital

5,000

97,000

10,000

I

2,200,000

11,100,000

1,100,000

$12,200,000

_•_ . . - .»

Table 4 (?•«• l of 2)(FS Table 6-4<

SUMMARY OF EXAMPLE ASSEMBLED ALTERNATIVE MO. 4 (AA-4)

Coit Estimates

Remedial Action

Soil

Excavate and remove hotspots

Demolish and remove asphaltparking lot south of blue warehouse

o Demolitiono Transporationo Disposal

Cap and teal entire lit* withmultilayer clay/membrane system

Groundvater

Extraction wells; groundratmr raaoraluntil 10 c«nc«r risk criteria are oat

Air stripping at 99 percent total VOCral

AnnualOperation &Maintenance

PresentWorth

Off-gas scrubbing by carbon adsorption

Facilities

Demolish and remove all buildingsand structures

o Demolitiono Transportationo Disposal

Demolish and remove concreteslab and loading dock

o Demolitiono Transportationo Disposal

Remove two open top onslte burledtanks

Seal all connections to northwesternstorm sever

Decontaminate and reline north*western storm sever segment

Clean 8" siphon and seal with grout

Rehabilitate existing scon(southeast side) end decontaminate

Seal existingveils with groat

production

$12,00049,00065,000

1,900,000

130,000

1,500,000

1,800,000

980,000610,000770,000

76,000150,000190,000

1,000

10,000

15,000

5,000

97,000

10,000

$17,000

50,000

16,000

460,000

$12,00049,00065,000

2,100,000

590,000*

1,600,000*

3,600,000*

980,000610,000770,000

76,000150,000190,000

1,000

10,000

15,000

5,000

97,000

10,000

GLT267/51-7

4 (P*fi 2 of 2)

OpcntioB

Additional

Inclndo pondttias'coot*)

(•e 10%)

TOOL

2.100.000

10,300,000

1.100,000

SU.MO.OOO

•All

of fcutiyuc soilfor tbi« actloa

ok 27 y«ir pvrlotf «t 10pnlod «t 10

, I.e., tteof +50 Co ~30 pnvoBC.

ported «t 10 pncoBC latorMC.will bo oKondaod by iogling friar to mA

2.700.000

13,700,000

1,400,000

$15,100,000

JaplOBOBtatlon

latoxoit.

0X2*7/31

CU2*7/51-«

Chapter 3PUBLIC COMMENTS - U.S. EPA RESPONSES

Public comments on the Feasibility Study Report for theChem-Dyne site were received by the U.S. EPA at a publicmeeting on December 3, 1984, and through written documentsreceived by U.S. EPA through December 28, 1984. These com-ments fell into the following eight major categories:

o Remedial Investigation (RI) Report Comments

o Feasibility Study Technical Analysis

SoilGroundwaterFord CanalOnsite Utilities

o Remedial Actions - Public Recommendations

SoilGroundwaterFord CanalOnaite Utilities

o Schedule for Remedial Action Implementation

o Site Risk* - Current and Future

o Remedial Contingency Actions

o Cost Versus Remedial Action Selections

o FS Comment Period

Public comments and U.S. EPA's responses are summarized inthis chapter. Comments in this chapter are edited and some-times paraphrased to combine similar comments under commontopics. The intent has been to present the full range oftopics and details of the overall comment set without lengthyrepetition. Texts of the specific verbal and written commentsare included in Appendix D.

REMEDIAL INVESTIGATION (RI) REPORT COMMENTS

During the public meeting in the City Council chambers atthe Hamilton City Hall on December 3, 1984, several commentsregarding the Final RI Report (May 22, 1984) were expressed.These comments were summarized in two letters to U.S. EPA.Because the comments were detailed and lengthy, separateresponses were prepared, combined, and sent directly tothose who commented in a letter from Don Bruce/U.S. EPA dated

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December 11, 1984. The letters with these Final RI Reportcomments and Agency responses are in Appendix A of this res-ponsiveness summary.

FEASIBILITY STUDY TECHNICAL ANALYSIS

Several comments concerned aspects of the technical discus-sions and analysis of the Chen-Dyne site and the alternativeramsdial actions presented in the FS. These comments andresponses were grouped as they pertained to soil, groundwater.Ford Canal, and onsite utilities.

son.Public comments:

1. FS should consider recent research that indicates thechemical effects of sosw wastes which render clay morepermeable (public meeting).

2. Removed material should not become another problem insome other place (public meeting).

3. How was a soil removal depth of 2 feet determined andhow are soil contamination hotspots to be identified?(Hamilton Appalachian Peoples Service Organization orHAPSO)

4. The final remedial package should include assurance andprovisions that Superfund will be responsible for cleanupof future botspot discoveries (Hamilton AppalachianPeoples Service Organization or HAPSO).

5. A more extensive offsite sampling is needed to determinethe true parameters of the contamination by toxic mater-ials (Izaak Walton League).

6. The soil is suspected of being contaminated up to 15 feetand of having hotspots erratically located. Chen-Dynesite operators kept poor records and there is also alack of scientific soil data. To start the remedialproject with a complete predetermined plan would benaive. (Jocelyn Hamm)

7. One alternative to soil removals is to remove hotspotswith testing being done at appropriate points duringcleanup. To remove 2 feet of soil from the remainingsite areas would be a negligent act. (Jocelyn Hamm)

8. To cap the site at a premature time during cleanup wouldbe a waste of resources. (Jocelyn Hamm)

Agency responses:

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1. The clay in the clay/loam and clay/membrane/loam capsconsidered for Chem-Dyne would not be in direct contactwith chemical wastes. Interactions between the clayand site contaminants are not expected.

2. Causing another contamination problem elsewhere is oneof the concerns considered with removal of contaminatedsite soils. Limited soil removal is incorporated inthe Agency's remedial action plan and care will be takento relocate the contaminated soils in an approved andinspected RCRA permitted landfill facility to minimizethe possibility of future problems.

3. Soil contamination removal to a depth of 2 feet wasbased on estimation of the overall site contaminantmass and the potential effect of soil contaminant infil-tration on groundwater. The 2-foot excavation depthwas based on estimated groundwater contamination reduc-tions with soil removal and various levels of sitecapping. The 2-foot excavation depth resulted in anestimated 90 percent removal of organic contaminants.Soil contaminant hotspots have been identified based onanalysis of soil samples and on judgment regarding pastoperations, aerial photographs, and visual appearanceof site soils. Identification of future hotspots duringthe progress of remedial actions on utilities at thesite should be guided by the sain* information.

4. The final remedial package includes contingency provi-sions to account for the discovery and removal of addi-tional "hotspots* of soil contamination if necessary.

5. Soil sampling was conducted offsite or outside the formerperimeter of the site for two reasons: first, to takebackground soil samples, and second, to investigateoffsite areas suspected to have been contaminated byChem-Dyne operations or runoff. The extent of offsitesoil contamination is limited to areas of reported dis-charges (e.g., west of the Chem-Dyne building along therailroad tracks) and runoff (e.g., south of the ware-house parking lot). Based on results of these samples,the site boundary was revised in the FS. During Chem-Dyne waste handling operations, contamination was alsodischarged to the Ford Canal and several fish and sedi-ment samples ware analyzed to evaluate canal conditions..These analyses led to issuance of the fishing advisoryfor the Ford Canal. Additional offsite sampling doesnot appear warranted at this time unless new informationregarding unknown offsite contamination is presented.

6. The amount of data available on soil contamination isnecessarily limited; however, sufficient data weredeveloped to evaluate remedial alternatives. The

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selected remedial plan for the Chen-Dyne site is detailedbut flexible. The remedial plans have explicit contin-gency provisions allowing adjustments to meet actualfield situations as they are identified.

7. Hotspot soil removal was considered as a reasonableremedial action in the PS. However, the FS concludedthat hotspot soil removal must be accompanied with alow permeability cap to minimize infiltration and themigration of organic contaminants that are in the soil.The overall removal of 2 feet of soil recognizes thatcontamination is widespread and erratic. Rather thanattempting to completely characterize contamination insoil with a large soil testing program in the remedialinvestigation, an alternative approach of soil removaloverall was evaluated based on a smaller set of soilanalysis data. In this evaluation, soil removal wasalways combined with a low permeability site cap. Inthis way, overall soil removal was considered as a gen-eral "insurance* approach. The final remedial alterna-tive selected for soil was removal of hotspots of soilcontamination and covering the entire site with a clayand membrane cap as opposed to removal of 2 feet ofsoil over the entire site.

8. The timing of cap placement is important to successfulsite rams illation. Capping must be done after all soilremoval is completed and site surface preparation isfinished. The low permeability site cap is critical tothe design of the soil remediation goals. Even withoutsoil removal, the low permeability cap will achieve thetwo goals of eliminating direct contact and minimizingendangerment caused by groundwater contaminated by con-taminant migration through site infiltration.

UKUUBIPmTBR

Public Commentsi

1. Contaminated groundwater should be extracted (publicmeeting).

2. POTW use for groundwater treatment should be rejectedbecause sludge would become contaminated (public meeting).

Use of the POTW as a groundwater treatment modality isunacceptable due to the number of hazards such an optioncould effect (HAPSO).

3. Rejection of the PACT treatment process should not bebased on cost alone (public meeting).

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Why is PACT, which is rated so high for its effective-ness, withdrawn from consideration simply due to cost;as the dollars for this cleanup are to come from thegenerators of the waste (HAPSO)?

4. EPA should pinpoint the extent and the rate of movementof groundwater contamination (public meeting).

5. Extracted groundwater should not lead to contaminationof any other environment (public meeting).

6. Air stripping is not a complete treatment technologyfor removal of all the organic pollutants possible atChem-Dyne; it is effective for volatile organics only(public meetings and HAPSO).

7. The Agency should identify the potential number of watersystems, and therefore the number of people who can beaffected by the toxic wastes known to be contaminatingthe aquifer. (IzaaJc Walton League)

8. The groundwater is contaminated with VOC's and othercontaminants onsite. However, offsite groundwaterremains a mystery to me due to lack of scientific dataand contradictions in the study. (Jocelyn Hamm)

9. The groundwater is contaminated with compounds thatcannot be completely broken down or bonded through anyalternative mentioned. However, granular activatedcarbon accompanied by air stripping or the PACT systemmay be the only solution. (Jocelyn Hamm)

10. Are the extraction wells "cone of influence" intendedto extend beyond the outer perimeters of the plume?(Robert C. Hubbard)

11. In determining the "cone of influence," were effects ofexisting industrial and municipal wells taken into con-sideration? If so, was full capacity operation or addi-tional wells also considered? (Robert C. Hubbard)

12. We do not see how the groundwater contamination canever be contained especially if contamination has beenfound at 65 feet. When you try to clean up the aquifer,all the money in the world cannot bring back our cleanwater once it is polluted. (The Chowning family andothers)

Responses:

1. The selected remedial action plan for the site includesgroundwater extraction over a period of several years.

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2. The comment recommending rejection of POTW treatment ofgroundwater recognizes one of the negative aspects ofthis alternative. The POTW alternative would be selectedonly after detailed pilot testing to investigate contami-nation problems which could include collection systemsludges and airspace, treatment plant atmosphere, treatedwater discharge, and sludge contamination. POTW treat-ment was not selected in the remedial action plan.

3. PACT was rejected not because of cost alone but becauseit did not provide greater advantages in return for thehigh cost. In this case, PACT is somewhat impracticalbecause it would require activated carbon treatment ofthe entire wastewater flow at the Hamilton wastewatertreatment plant. The evaluation of remedial alterna-tives is independent of the source of remedial funding.Onsite treatment alternatives are favored over PACT.The source of cleanup funds was uncertain at the timeof this evaluation; therefore, the Agency could not•Slums that Chem-Dyne would be a generator-financedcleanup.

4. The extent of groundwater contamination has been des-cribed in the RI report. The rate of contaminant migra-tion was estimated in the FS. Both the extent and rateof contamination are described sufficiently to evaluateand select remedial actions. The implemented groundwaterremedial actions will include monitoring and contingencyplans to control and adjust the remedial measures asnecessary to maintain proper performance. (Refer toadditional discussion on monitoring in the section,•Remedial Contingency Actions" on page 3-17).

5. To minimize the spread of contamination from theextracted groundwater, the groundwater will be treatedby air stripping and vapor phase carbon adsorption priorto release. Complete treatment technology selectionand sizing will be based on bench or pilot tests ongroundwater samples during the final design of theremedial actions.

6. Air stripping is effective for removal of volatileorganics only. RI data indicate that volatiles are thepredominant organic contaminant category in the extractedwater. However, if monitoring of extracted and treatedgroundwater reveals the need for additional treatment,other treatment technologies will be added to the treat-ment system to meet discharge goals. If nonvolatileorganics such as base/neutral or pesticide compoundsoccur in the extracted groundwater, an additional treat-ment technology of activated carbon adsorption, forexample, would be added to the system.

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7. Groundwatar contamination attributable to the Chem-Dynesite has not been found in any water supply or produc-tion systems presently used for drinking water. Partof the endangerment attributed to groundwater describedin the FS is based on the potential use of a contami-nated water supply. The scope of the potential con-tamination problem is discussed in Chapter 2 of the FS.The Hamilton south well field is the focus of concernin Chapter 2 although the Fairfield well field andCincinnati water supplies could also have been includedin the discussions. Alternatives in the FS are selectedto mitigate contamination in these water supply sourcesas well as the Hamilton well field.

8. Estimates of volatile organic contamination offsite arepresented in the Final Remedial Investigation Report.These estimates are based on groundwater sampling fromseveral offsite monitoring wells. The "contradictions"mentioned by the comment must be better described beforeresponses can be offered.

9. Most groundwater contaminants identified in the remedialinvestigation are volatile organic compounds. Thesetypes of compounds can be removed by either air stripping,granular activated carbon, or both. PACT would involvethe POTW and would be very expensive and somewhat imprac-tical because it would require treatment of all incomingsewage at the Hamilton wastewater treatment plant.Onsite treatment was favored over PACT.

10. Yes, the wells for groundwater extraction are arrangedto intercept groundwater beyond the outer perimeter ofthe plume.

11. Other production wells were considered in the endanger-ment assessment to evaluate the potential for productionwell contamination. For the extraction wells, theeffects of other production wells was considered throughthe use of the measured local groundwater gradientswhich included the affects of all local production wells.Future local well expansion could be accommodated byincreasing extraction pumpage.

12. Groundwater movement can be controlled to a great extent:locally by extraction wells properly placed and operated.These walls create a groundwater "valley" or barrierwhich controls the escape of the contamination plume asit migrates along the natural direction of groundwaterflow. The comment on money and cleanup is exaggerated,of course, but it emphasizes the valid point that ground-water remediation is expansive and costs increase dra-matically as the level of cleanup increases.

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FORD CAHAL

Public comments:

1. Public consumption of fish from the Ford Canal must beconsidered a serious health problem. Steps should betaken to restrict access and educate people to dangersof fish contamination in the Ford Canal and Great MiamiRiver (public meeting).

2. PCB contamination in fish samples from the Ford Canalshould be considered related to site contamination(public meeting).

It is illogical to proclaim that the PCB's contaminatingthe fish (in the canal) could in no way be attributableto Chem-Dyne; which is the Agency's contention for notaddressing the matter through Superfnnd (BAPSO).

3. Mercury contamination of Ford Canal sediment and pos-sibly fish is a serious public health concern (publicmeeting).

4. Fish kill incidents were directly attributed to theChem-Dyne PCB contaminants (public meeting).

Agency responses t

1. Public consumption of fish from the Ford Canal is aconcern in terms of public health. Based on the recom-mendation of the Agency's project officer in 1983, theOhio Department of Health (ODE) issued a fishing advisoryfor the Ford Canal near Chem-Dyne. This advisory ispresently in effect. The ODE is also considering addi-tional studies of the canal and Great Miami River.

2. PCB's were identified in similar concentrations in fishupstream of the hydroelectric dam in the canal and infish from the Great Miami River upstream of the riverdam near the canal outlet northwest of the site. There-fore, while PCB's in downstream canal fish could befrom the site, "background" concentrations in fish fromthe area preclude making the clear link to the site.

Because PCB concentrations in the downstream fish fromthe Ford Canal are similar to concentrations in canalfish upstream and concentrations reported in fish tis-sues from upstream reaches of the Great Miami River,PCB releases from the site cannot be conclusively iden-tified as the cause of PCB contamination in the down-stream canal fish. Further, PCB's were not identifiedin either the storm sewer water sample or downstreamcanal sediment. Without the clear link of fish

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contamination to the site, CERCLA action is not possible.Other actions such as the health advisory issued throughthe Ohio Department of Health are indicated and havebeen implemented. '

3. Mercury was not identified in high concentrations indownstream canal sediment samples. Mercury compoundswere reportedly included in Chem-Dyne wastes and mercurywas identified in two downstream sediment samples.However, mercury was also identified in similar concen-trations (0.31 to 0.55 mg/kg) in three out of fourupstream sediment samples. Mercury concentrations inextracted groundwater will be monitored to mitigate thepossibility of mercury discharge into the canal fromextracted groundwater.

4. The fish kills related to Chem-Dyne were reportedlycaused by release of concentrated pesticides and pesti-cide wastes, particularly endrin which is exceptionallytoxic to freshwater fish. PCB's were not identified ashaving caused the fish kills.

ONSITE UTILITIES

Public comments:

1. All onsite buildings should be demolished and eliminated.Existing buildings are attractive to children andextremely hazardous (public meeting).

2. Onsite building demolition should not be excluded fromremedial action consideration because of cost (publicmeeting).

3. Because steam cleaning is superficial and temporary atbest, it is unacceptable as a remedial action for thestructures (HAPSO).

4. The site calls for more investigation into sources ofcontamination, extent of contamination, and locationsof underground facilities before any further action istaken dealing with underground structures. (Jocelyn Hamm)

Agency responses:

1. Demolition and disposal of all onsite buildings was oneof the alternatives considered in the feasibility study.Comment on the "attractive" nature of the buildings isnoted. The attractive hazard quality of these buildingswas considered in the feasibility study. The remedialaction selected for Chem-Dyne includes demolition ofall onsite buildings. Building rubble will be disposedof both on and offsite as appropriate.

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2. The cost of building demolition was one of the evalua-tion factors. Other factors included public acceptance,technical feasibility, and benefits to public health.Cost along was not used to make the selection ofremedial actions on the buildings.

3. Steam cleaning, as considered in the FS as an alterna-tive remedial action, would have been performed withmonitoring and sampling to check the thoroughness ofthe decontamination process. Steam cleaning is gen-erally effective only for nonporons materials such asmetal; porous materials like wood and masonry tend tosoak up chemical contaminants and steam decontaminationcannot effectively remove the penetrated material.Where properly employed, steam cleaning can be an effec-tive and permanent remedial action which is why it iscarried forward in the PS as an alternative remedialaction. Its applicability is limited and it onlyaddresses chemical contaminants, not the "attractivenuisance" problems. Complete demolition of buildingshas been selected for the remedial action plan; there-fore, decontamination will not be necessary.

4. Extensive information on specific sources, extent, andlocations of contamination and buried utilities is notnecessary to implement a remedial action or set ofactions which controls releases from buried utilities.The site cap will control infiltration and a deep peri-meter cutoff trench with utility sealing by grout willcontrol lateral migration. Ramadial actions whichaddress buried utilities, site cap, and perimeter trenchwith grout seals, can be evaluated without detailedinformation regarding buried utilities.

REMEDIAL ACTIONS — PUBLIC RECOMMENDATIONS

Several comments expressed opinions about which specificremedial actions should be selected for the Chem-Dyne site.Tfcese comments and responses are presented below.

son.Some comments expressed the opinion that all contaminatedsoil should be removed from the Chem-Dyne site. Completeremoval of contaminated soil was recommended by commentatorsfor a variety of reasons. The reasons for complete contami-nated soil removal have been compiled and paraphrased below.The responses are presented following the comments.

Those commenting on soil remedial recommendations includethe following: Hamilton City Manager, Department of Health,City Planning Commission, City Council (by ResolutionNo. R84-12-69), Gilbert Insurance Agency, Parrish and Haid

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Insurance, Conastoga-Rovers and Associates Limited, and severalprivate citizens.

Public Comments:

1. As long as contaminated soil remains at the site, therewill be percolation of toxic materials into the aquiferand doubts regarding damage to the aquifer and continuedhealth risks will persist in the minds of all citizens.(J.P. Becker and others)

2. Capping is not a long-term, fool-proof remediation methodto protect the aquifer. Capping is considered a short-term and unsafe method of protection. (William J. Karwischand others)

3. The most heavily contaminated soil should be removedfrom the site (public meeting).

4. Site cap should be loam over clay with revegetation(public meeting).

5. There is no technical justification for extensive exca-vation of soils from the Chem-Dyne site. A surface capwill accomplish the same objectives without the problemsthat are associated with offsite disposal.(Conastoga-Rovers and Associates Limited)

6. Removal of contaminated soil will cause dust and odorsto be released. Recommend a concrete cap with minimumdisturbance of soil onsite. (Mary Estep)

7. Instead of removing soil and capping with clay, pourblacktop or concrete over the site to make tennis courtsor a parking lot. The concrete or asphalt would preventany rain from washing any contaminants down in the gravelaquifer and shorten or eliminate the 27 years expectedfor natural migration to occur. (Timothy G. Korver)

Agency responses:

1. Soil contamination consists of inorganic and organicmaterials. Inorganic elements were primarily associatedwith the upper 5 feet of soil. Organic materials includea wide range of compounds with a wide range of behaviorin soil. Some of the organic compounds, including pes-ticides and other high molecular weight compounds, tendto move very slowly in soil and these are found in nearsurface soils. Other organic contaminants, particularlychlorinated solvents, move more rapidly through soiland these compounds are found from the soil surfacedown to groundwater about 25 feet deep.

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To remove all contaminated soil, practically all sitesoil would be excavated to an approximate depth of25 feet. Because of the large volume and deep pene-tration of contaminated soil, an alternative to completesoil removal was evaluated. The alternative had toaddress two problems caused by contaminated soil:direct physical contact and groundwater contaminationby leachate.

Site capping is a technically workable and demonstratedremedial action for soil contamination as found at Chem-Dyne. Such caps are planned and engineered systemswith finished thicknesses of about 4 to 5 feet. Sitecaps greatly retard infiltration and conduct rainfall/snowmelt runoff away from the site. Caps do requireregular maintenance and periodic replacement (assumedin the PS to be every 30 years at a minimum). The cap-ping monitoring program selected for the site includescap monitoring and periodic synthetic liner testing todetermine cap condition and the possible need for replace-ment. In iiimmiiif. capping is considered a practicallong-term remedial action that does provide reasonableprotection of the aquifer.

A final consideration for the site capping alternativeis that Chem-Dyne will have a groundwater monitoringand extraction well system in place. The performanceof the cap system will be monitored through the qualityof groundwater moving below the site. Concerns regardingdamage to the aquifer and associated potential healthrisks will be addressed with data from the groundwatermonitoring system.

soil removal, limited to areas of high chemicalcontamination, will be done at the site to give someextra margin of protection against chemical wastemigration. The feasibility study evaluation concludedthat no reasonable amount of soil removal could alonecompletely remedy soil contamination at the site.Therefore, the site requires a high qualityr low permea-bility cap to reduce both the possibility of physicalsoil contact and infiltration of rain through the con-taminated soil. The soil contamination remedy is thesit* cap while soil removal is considered an extra step.

The loam over clay cap system was one of the two capsystems considered in the feasible study as alternativeswhich meet the remediation goals for soil. The capselected in the remedial plan is composed of loam overmembrane over clay. This cap was chosen to comply withRC8A criteria and to more effectively reduce infiltra-tion. The surface will also be revegetated to controlerosion.

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5. Technical justification for extensive soil removal andsurface cap was presented in the FS. Some limited "hotspot" soil removal was considered as an extra measureof protection to be included with1the cap.

6. Dust generation has been recognized as one of the draw-backs or problems associated with soil excavation.During any soil excavation at the site, specific dustcontrol procedures will be required of the contractors.A concrete cap is not a favored cap material becauseconcrete requires frequent maintenance to repair cracksand settlement damage.

7. Capping with concrete or asphalt is a possible cappingmethod, but both methods require careful maintenance tominimize leakage. Site reuse as a tennis facility orparking lot was considered in the final selection ofcap method. Site reuse was judged impractical and wouldinterfere with maintenance of the cap. Remedial actionswill maintain access to onsite wells/ water treatment,and the hydroelectric facility.

GROUNDWATER

Several comments were that contaminated groundwater shouldbe extracted and treated to remove chemical contaminantsprior to discharge.

Comments regarding additional monitoring of the groundwatercontamination plume and treatment system were addressed inthe previous section, Feasibility Study Technical Analysis,under the groundwater portion.

Public comments:

1. Extract and treat the groundwater until there is notrace of pollution remaining. (Pamela E. Anderson andothers)

2. Time problems, permit problems, construction problemsall relate to deep well injection. Why contaminate a3,000 foot deep zone we know practically nothing about?(Timothy 6. Korver)

3. Based on my experience, I offer recommendations onextraction well location, design, screen, and drillingmethod. (Timothy G. Korver)

Agency response*:

1. Groundwater extraction was predicted to reduce concen-trations of volatile organic contaminants to low con-centrations. However, it is likely that detectable

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concentrations of some contaminants would remain evenafter several years of groundwater extraction. Verylow concentrations may remain in the groundwater if itbecomes impractical to continue extracting and if publichealth and welfare are adequately protected. Similarly,detectable concentrations of contaminants may remain inthe treated groundwater prior to discharge from thetreatment system if public health and welfare are ade-quately protected. The selected alternative to beimplemented under the forms of the Consent Decreerequires the groundwater to be extracted until the levelof contaminants can be reduced no further.

2. These problems related to deep well injection wererecognized in the feasibility study and considered indeep well evaluation. Deep well injection was not sel-ected for the final remedial action plan.

3. The well design and placement recommendations are wellreceived and will be referenced in the design of theextraction well system. (Refer to the complete contentsof Korver's letter in Appendix D of the Responsiveness

FORD CABAL

Three specific comments were received on remedial actionrecommendations for the Ford Canal. One comment expressedgeneral disagreement with the FS.

Public comments:

1. The •no-action" plan for the Ford Canal sediment isunacceptable to the community (BAPSO).

2. The canal has been written off as not being a threat tobiotic or antibiotic ecosystems. The canal is a threatto these systems and it could be an avenue to humanexposures. (Jocelyn Hamm)

3. There are also hotspots in the Ford Canal particularlynext to the Ford Park area. The City is presently fil-ling in this area, and if action is not taken immedi-ately to determine the extent of contamination, we willhave a successful coverup. (Jocelyn Hamm)

Agency responses:

1. On the basis of the RI data and the endangerment assess-ment, no remedial action is warranted for the Ford Canalunder the provisions of CERCLA. Sediment removal fromthe canal would be expected to redistribute any contami-nation in the sediments over a wider area in the canal

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and Great Miami River. Because existing storm sewersmay be continuing to drain organic priority pollutantsinto the canal, the selected remedial plan incorporatescutoff and sealing storm sewers to prevent future dis-charges to the canal.

2. Based on results of the canal sediment and water analy-sis, as well as fish tissues, remedial actions do notappear to be warranted in the Ford Canal. The remedialinvestigation indicated that the storm sewers may bedraining low concentrations of priority pollutantorganics into the canal. Therefore, the selectedremedial plan includes provisions for sewer cutoff andsealing to prevent future discharge of contamination tothe canal.

3. The Ford Park area is understood to mean the ballparkand swimming pool facility immediately east of the Chem-Dyne site. The Agency has no information to suggestthat there is chemical waste contamination in this por-tion of the Ford Canal. If any new observations orinformation are available, these data should besubmitted to the U.S. EPA Region V and the Ohio EPA assoon as possible.

Based on the present information regarding Chem-Dyne, thefollowing responses are offered. The Ford Park area isupstream of the site and upstream of the hydroelectric damin the canal north of the old Ford factory. It is veryunlikely that runoff from the Chem-Dyne site could haveaffected the canal near Ford Park. Unless Chem-Dyne wasteswere deposited in the area mentioned, the source of the su--pected contamination cannot be reasonably related to Chem-Dyne. Again, if additional information can be presented, aninquiry into this area of the canal may be warranted.

ONSITB UTILITIES

Several comments expressed the recommendation that the Chem-Dyne building should be removed from the site because it isan attractive hazard, it is chemically contaminated, and itis partially damaged (by fire) already. Some comments calledfor the removal of all contaminated buildings (including theChem-Dyne building). Finally, some comments simply recom-mended the removal of all buildings onsite.

One comment suggested that the buildings could be buriedonsite.

Public comment:

1. If the buildings were turned into rubble, they could beburied in or under the pavement. (Timothy G. Korver)

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Agency response:

Demolition of the Cbem-Dyne and other onsite buildings wasone of the remedial alternatives carried forward in the FS.The chemical contamination of the Chem-Dyne building wasrecognized as well as the possible contamination of severalother buildings. The attractive hazard nature of thesedilapidated structures was also recognized and was con-sidered in the selection of a final remedial action which isthe demolition and disposal of all onsite buildings.

1. Burial of some selected building demolition debris is acomponent of the selected remedial action plan in con-junction with a high quality, low permsability sitecap.

SCHEDULE FOR REMEDIAL ACTION IMPLEMENTATION

Public comment:

1. Time is of the essence for remedial actions at the site.Remedial work should begin as soon as possible (publicmeeting).

2. The City of Hamilton requests that the U.S. EPA proceedwith all possible haste to correct the three criticalenvironmental problems (contaminated soil, groundwater,and site buildings) in order that further contaminationof the aquifer can be minimized (City Council ResolutionR84-12-69).

Agency responsest

1. The Agency has procdeded through the analysis and deci-sion process with deliberate speed so that remedialactions for the Chem-Dyne site can be implemented assoon as possible. Negotiations with settling defen-dants have been conducted with emphasis on timelysettlement to hasten the implementation of effectiveremedial actions.

2. The Agency recognizes that one of the primary reasonsfor timely remedial action is to minimize further con-tamination of the aquifer. In this regard, some con-taminated soil has been removed from the site andbuilding demolition is expected to occur this year.

SITE RISKS — CURRENT AND FUTURE

Public comments:

1. The public must be informed of the health risk causedby the site now and in the future. As the groundwater

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plume moves, any new or different level of risk shouldbe made public (public meeting).

The Hamilton residents have a right to know the healthand environmental risks they are facing. It is theU.S. EPA1s responsibilitv to provide that information(Mary B. Loeffler).

2. The Agency should more fully inform the public as towhat toxic materials are present and the hazards thatthe known substances present to the health of the citi-zens (Izaak Walton League).

Agency responses:

1. The present public health risk is described in the FS,Chapter 2, Endangerment Assessment. As remedial actionsare implemented and frequent routine monitoring begins,regular releases of data will be available to the publicfrom the Agency. If risks to public health arise atany time, the Agency will notify the public.

2. The endangerment assessment in Chapter 2 of the FSaddresses the toxicity and hazards of the known sub-stances at the Chem-Oyne site. More detailed listingsof the chemicals identified at the site in varioussamples are presented in the Final Remedial Investiga-tion Report issued in May 1984.

REMEDIAL CONTINGENCY ACTIONS

Several comments addressed the need for monitoring and contin-gency actions during remedial work. These comments havebeen combined and paraphrased below.

Public comments:

1. The Agency should continuously sample and monitor duringthe remedial action implementation to check performance.(Public meeting)

2. If the remedial performance fails, the Agency shouldcorrect the situation to safeguard public from unneces-sary risk. (Public meeting)

3. Monitoring data should be made public in a timely andopen manner. (Public meeting)

Agency responses:

1. Frequent regular monitoring of the site during remedialimplementation is part of the selected remedial actions.

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Monitoring incorporated in the remedial plan includesthe following:

a. Sampling in a manner and at a frequency requiredby the HPDBS permit which allows the discharge oftreated groundwater to the Ford Canal.

b. Testing air emissions from the air stripper accord-ing to requirements of the permit to install andpermit to operate the system.

c. Sampling groundwater prior to startup of remedialextraction, during groundwater extraction, and for5 years after termination of the operation toassess performance of the system, compliance withremedial goals, and the possible need for correc-tive actions to improve performance.

d. Measurement of water levels in all monitoring wellsand new piezometers (wells designed for water levelmeasurement only) on a semimonthly and, later,monthly schedule during groundwater extraction tomonitor the hydraulic gradients generated bygroundwater extraction.

e. Programs of sampling and analysis to support thesafety plan for onsite workers.

f. Air measurement and analysis programs to evaluatethe effects of remedial activities on the neigh-boring I'ommnni \y and provide for public safety.

g. Programs for assessing performance of the site capincluding the synthetic liner material.

2. Linked to the monitoring program, all remedial actionshave contingency plans for adjustment of the remedialactions to account for changes in performance.

3. All site monitoring data will be made public by theAgency on a regular basis.

COST VKBSUS REMEDIAL ACTIOH SELECTIOHS

Public comments:

1. The financial limits of the remedial fund should notlimit the remedy selected (public meeting).

2. Whatever is decided for remedial actions at Chem-Dyne,the decision must be based on health and environmentalfactors, not saving money. (Mary Loeffler)

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Do not be limited in your imagination or by the amountof funds - especially do not be limited to funds col-lected from third parties. (Richard Haird)

Agency responses:

1. The cost of any remedial action is one of the criteriain every evaluation at every site including Chem-Dyne.However, cost is secondary to the goal of protection ofhuman health, welfare, and the environment. Within therange of remedial alternatives which protect humanhealth, welfare and the environment, cost is evaluatedas one of the selection and judgment criteria.

2. The remedial actions to be implemented at the Chem-Dynesite have been selected with the primary goal of pro-tection of human health and the environment. Severalapproaches or remedial alternatives considered in theFS fulfilled this primary goal. Cost was one of theconsiderations used to select among the different, yetacceptable, remedial approaches.

PS COMMENT PERIOD

Public comment:

1. The time allowed for public comment on the FS reportwas very short, from the time the document was avail-able during the week of November 19 until the end ofFriday, December 14, 1984 (public meeting).

Response:

1. Since the time of the public meeting and this comment,the comment period was extended through Friday, Decem-ber 28, 1984.

GLT267/52

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Appendix AOXFORD AUDUBON SOCIETY AND HAPSO

COMMENTS AND RESPONSES ONCHEM-DYNE FINAL RI REPORT

GLT267/53-1

Oxford Audubon SocietyConservation CommitteeSeptember 28, 1984

Don BruceU.S. Environmental Protection AgencyRegion VRemedial Response Branch230 South Dearborn StreetChicago, IL 60604

Dear Don,

The nation has slowly become aware that environmental crisesdo not always belong to someone else, someplace else. In ourindividual communities we are being forced to recognize theunpleasant facts that environmental crises belong to each of us.This realization has been particularly severe and unsettling to theresidents of southwestern Ohio as we have faced the complexitiesand enormity of the environmental insult represented by theCham-Dyne facility in Hamilton, Ohio.

As citizens concerned with environmental quality we have beenclosely following the SPA's study of the Chen-Dyne Site. Seekingto understand the issues, we reviewed the EPA's findings that werepresented in the Final Remedial Investigation Report. In doing so,we hoped to stimulate reasoned debate and voice our concerns oversome shortcomings which we have detected, while we emphasize thatwe are not experts in cleaning and restoring toxic waste dumpsites, we point out that our efforts entailed many hours ofcareful, detailed work. While not experts, the points we raiserequire no specialised knowledge beyond a good grasp of scientificprinciples and practices.

We divided the subject area, and will subsequently present ourresults, in the following fashions On-Site Structures; Soil;Groundvateri and the Pord Canal.

A major shortcoming of the investigation was inadequateanalyses of areas of documented or suspected contamination.Adequate documentation of contamination is essential to providesufficient information upon which to organize and successfullyexecute an effective cleanup. As an example, the report mentionsthe existence of two partially buried tanks which were used for thestorage of liquid wastes. No information pertaining to theircontents or the integrity of their sub-surface portions ispresented. Further, the OBPA suspects the existence of more buriedtanks just east of the Ford Factory Building but their presence hasyet to be confirmed or denied. Surely, this would constitute

critical missing information.

The report documents that, upon inspection, the BoilerBuilding was found to have an electrical conduit penetrating thesouth wall; this conduit was draining contaminated fluids onto thefloor, mo steps were taken to locate the source of thecontaminants which remains unknown. To our knowledge, the remedialinvestigation has not conducted tests to determine the extentand/or existence of contamination of other onsite utility piping;piping which was identified by the report as a possible avenue forthe spread of contaminantsI

An investigation into the possible contamination of the FordFactory Building was never mounted. The apparent reason for thisomission, aside from the fact that the building was not "visuallycontaminated", was that no knowledge of the storage of 'significantamounts of Chem-dyne waste* exists. Certainly when we are dealingwith the potent carcinogens that have been found on the site, thereis no need for a large quantity of material to be present before itis "significant". Prudence dictates that no onsite facility shouldbe dismissed from investigation on such grounds, particularly withthe haphazard state of record keeping that prevailed at Chem-Dyneduring its active phase. Similarly, no samples were taken from theGarage, which was known to "have been used for waste storage" andwhose "floor was visibly contaminated".

The detection of six known carcinogens in the single sampletaken from the storm sewer main raises vital and urgent questionsconcerning their origins and the dynamics of the entire storm sewersystem. These questions were not addressed in the report. It isapparent from these brief comments that additional investigation ofen-site structures and utility hardware is justified in order toestablish an adequate data base. At the moment it is difficult tounderstand bow statements can be made with confidence concerningthe extent of contamination and route of contamination flow.

The soil investigation section of the Final RemedialInvestigation Report raises several questions regarding soilsampling protocols and associated •assumptions* of contaminantbehavior. Many assumptions which have been made require a moredetailed explanation before they can be accepted. For example, theword significant is used rather loosely to define the amount offlooding necessary for surface runoff to carry contaminated soilfrom the site. Significant, in this non-statistical usage isunacceptably subjective. What *CR the conditions that can bedefined as 'significant* for runoff to occur? Additionally, toassume that "current site topography* ux not allow for themovement of contaminated runoff to areas offsite is naive and, ifmistaken, very unfortunate. Such statements are unacceptablewithout substantiated facts. Of course the problem arises of howsubstantiated facts are obtained when less than mimimal numbers ofoffsite soil samples were taken?

Further doubts are raised concerning the accuracy of the soilstudy when the evaluation of inorganic contamination offsite isconsidered. "Background" samples that were taken offsite presentvalidity problems, two were heavily contaminated and could not beused for background. The remaining two offsite samples listed ashaving come from an "unaffected" area also revealed contamination,albeit to a lesser degree. The fact that contaminated samples OS-3and OS-4 were taken offsite, in close proximity to the waste site,indicates that runoff did occur despite site topography. Finally,we object to the term "unaffected area". The area was manifestlyaffectedl

Considering the history and extent of contamination to date itwould appear that only the tip of the iceberg has been found duringthis remedial study. This should come as no surprise since thesampling scheme was not statistically sound. The number of soilsamples taken both outside and inside are insufficient toaccurately estimate contamination. Estimating the extent ofcontamination offsite requires more samples than were taken andbackground should really be chosen as such. It would now seemdesirable to further investigate the soil contamination problemusing proper statistical analysis. A sampling protocol indicatingthe type of sampling being done (i.e., stratified, etc.) must bebased on stastistical sampling strategy. Such a strategy was notmentioned in the report, yet there was continual use of thestatistically loaded term "significant."

We would urge you to reconsider the accuracy of the studyespecially for offsite areas and in all directions (concentric tothe site). Residential neighborhoods mast be included. Samplesize offsite was too low to allow for statistical evaluation, thesame may also apply to other areas sampled. After evaluating thesoil investigation data presented, it is clear that more datagathering is necessary before statements about contaminated areascan be made.

Throughout the report not enough attention is given to thereal problem presented by the toxic contaminants found in the soil.There has been no satisfactory explanation about the toxicity ofthe materials detected both in and out of the facility. Anexplanation along these lines is necessary so that those not havingknowledge of the chemicals can evaluate findings. Finally, one ofthe many inaccurate statements that is salient in the soilinvestigation report appears on page 3-12. To say that phenol isnot particularly toxic is both wrong and misleading.

Grotindwafc»f/Ford Canal

The Technical Memorandum of Dec. 20, 1983 (Vol. 2A of 2)provides an historical survey of the Chem-Dyne site. In 1917, theMiami Conservancy District leased the site to the Hamilton andRossville Hydraulic company, which operated at least two canals anda reservoir on the site. In 1919, the west canal and reservoirwere filled in. Using the Figures in the technical memoranda, thiswest canal can be seen to occupy the western border of the present

Chem-Oyne site. Similarly, the reservoir occupies the south tosoutheastern border. Presumably, surface waters, such asrepresented by the canals and reservoir, could only be maintainedover a porous aquifer if they were underlain by an impervious claybarrier. In describing the subsurface soil characterization, theSite Geology Section in the Summary Report presents evidence thatthe canal and reservoir can yet be distinguished.

The review of onsite large-container bulk waste storageindicates that Tanks 1 through 7, and 13 may have been situatedatop the west canal. These bulk tanks contained the largestconcentrations of chlorinated pesticides and aromatic hydrocarbons.Coincidentally, there is a pattern of •»»•«•

works as. routes of contaminant transport via a multiple datesampling' analyses of mobile toxicants over a significant portion ofthe beds.

The major trend of groundwater monitoring to date indicatessouth-southwest migration of low molecular weight volatileorganics. However, only one well is more than 400 feet to thesouth of the site and only a single well is more than 400 feet tothe southwest of the site. This occurs despite statements from thisFIT report indicating probahi* contamination 650 feet offsite. Thewells for the city of Hamilton, located south of the site, are themajor human concern. More detailed and frequent resolution of themigration pattern are essential as noted in the summary evaluation.

The data base for prediction of migration is based upon wellsdrilled 30-60 feet. However, the report indicates contaminationbelow at least 65 feet in one of the few deep wells. The Championpumping wells may be encouraging migration westward deep below theGreat Miami River. Surely, any remedial action must include rapid

,,,d expansion of the monitoring well network for mobile chemicals not^ only in a broader south-southwest surface area, but also in the

depth profile.

Limited groundwater sampling seems to indicate a generallygreater rate of groundwater movement to the west of the site as theGreat Miami River is approached. It would seem reasonable andprudent therefore, that instead of deriving a migration profilebased upon the range of all measured values, rates of transport fortoxic materials from Chen-Dyne should be calculated on a sector bysector basis incorporating hydrogeological parameterscharacteristic of those sectors.

The lack of a coherent pattern of material migration ingroundwater is made obvious by examination of the tables inAppendix B, Volume 2A of 2. For example, 1,1,2-trichloroethane atMW-15 sampled by CH2M varied from 12,000 ug/1 during April 1983 to

||| 3,400 in July to 29,000 in October. Acetone, on the October 1983sampling date (CH2N), varied on an east west gradient from 49,000ug/1 at the MW-15 site (approx. 100 feet west of Chem-Dyne); to540 ug/1 at MW-18 (approx. 500 ft west of Chem-Dyne)j to 4900 ug/1at MW-19 (approx. 1200 feet west of Chem-Dyne). what level ofconfidence can be attributed to the values reported asrepresentative of that site? Logic suggests that the samplingregimen may have overlooked episodes when toxicant concentrationswere conceivably several orders of magnitude greater than thosereported.

Similar criticisms can be leveled at the cursory dismissal ofthe Chem-Dyne site as responsible for contamination of the FordCanal Area. Can the limited temporal and geographic samplingassure us that there has not been, nor will be, significantcontamination of this aquatic system? Sampling of the fish specieswas haphazard and difficult to interpret biologically. Differentspecies were sampled at up and downstream sites, and varied as totrophic levels (herbivores compared to carnivores). Apparently,

tba fiab that wara sampled wara not aged ao we hava no idea howlong thay had baan exposed to tha watara of tha pord Canal.Conaidaring tba limited naefnllneaa of tha data obtained from thefish studies and conaidaring the known abilities of variouslong-lived toxina to migrate, both biotically and abiotically, wabelieve that it ia premature and irresponsible to dismiss anyeffects of toxina entering the Pord Canal from tha Cham-Dyne aitaaa inconsequential.

In summation, wa hava addraaaad a variety of concerns. Wefaal that it ia imperative that remedial decisions ba baaed uponaolid information in order to insure that a aacond "final* round ofremedial daciaiona naad not ba made. There ia little doubt thatconducting a atody of this kind requires a Major effort, wa aregrateful that it baa baan attempted.

There are, however, aariona queationa that reaain unansweredand naada that remain unfulfilled. We trust that tha work will bacompleted with these qaaationa and concarna being addreaaad in athorough and timely fashion. We aak that yon respond to theqaaationa that wa hava raiaed in addressing the next phase of theCbemdyne aita cleanup.

Sincerely,

Andy Garcia-aivera John Lahorra713 Sooth Locust 10 PapparwoodOxford, OB 45056 Papper Pike, OH 44124513-523-5576 216-831-4043

_ *oja115 B. Oniveraity Avenue 733 B Daniel DriveOxford, OB 45056 Oxford, OB 45056513-523-4525 513-523-5987

6 David Reeae Paul B. Woods716 Sooth College 219 Worth BinApt §42 Oxford, OH 45056Oxford Sqoara ApaiOxford, OB 45056513-523-7210

cc) Ohio EPACity of HamiltonHAPSO

HAMILTON APPALACHIAN PEOPLE'S SERVICE ORGANIZATION522 BUTLER STREET • HAMILTON, OHIO 45011

(513) 868-O95O

September 13, 1984

Mr. Don BruceU.S. EPA, Region V230 South Dearborn StreetChicago, Illinois 60604

Dear Mr. Bruce,

It was good talking to you again last week. I was pleased to learn that the fea-

sibility study is moving along so well. I will be looking forward to receiving a copy

of the document in the near future and to receiving notice of the next public meeting

date.

As I mentioned during our phone conversation, I would like to direct a few com*

ments and questions to your office.

*1. In volume 2A of 2 of the Remedial Investigation Report you have Included ahistorical map of the site (Figure 3). As we discussed earlier, our con-sultants at Miami University stated that this map pointed out a number ofpossibilities for natural conduits which would affect groundwater flow be*neath the site. Thus, given the proper attention, the map may indicate areaswhere additional testing for soil and groundwater contamination should occur.Futhermore, this map may lend support to the possibility of local fish con-tamination having Chem-Dyne as its point of origin.

2. In regard to the PCB contamination of the fish, am I correct in my understand-ing that the U.S. EPA will not address this problem unless it is found to bedirectly attributable to the Chem-Dyne site? If this is in fact the case,will you be submitting a recommendation for another party to investigate thismatter futher?

3. In the* feasibility study, will you be addressing the issue of future moni-toring—both on-and-off-site? That is, will the U.S. EPA periodically checkon the effectiveness and efficiency of the below-surface cleanup plan it im-plements? Also, if another pocket of contamination is found at a later date(post-cleanup) which was caused by Chem-Dyne and was not addressed in thefeasibility study, will the U.S. EPA cleanup such an area as well(at that

due to the nature of its origin*?

A United Way Agency

Ihank you for your tlae, attention and concern. I will be looking forward to

hearing froai you soon. .

Sincerely, . til

Ŝkvwkx̂̂ >-"" Judy A. Gllleas

•̂"""̂ Executive Director

*P.S.—In regard to lte» ouaber one* you amy contact Or. Poje' at #(513)529-3624 or at* (313)529-3451 to leave a •Maage If you would like additional Information onor the rationale behind die University staff's findings in this Batter.

DEC 12 1984

December 11. 1984

Ms. Judy A. 6111ensExecutive DirectorHamilton Appalachian People's

Service Organization522 Butler StreetHamilton, Ohio 45011

Oxford Audubon SocietyConservation Committee

September 2S. 1984; Obcford Audubon Society Comments;

OJISTTE STRUCTURES

Page 1. Paragraph 1

Tht two partially burled open-top tanks were sampled In previous Investi-gations before the RI study. Based on these data, removal of the liquidsand sludges during the 1983 surface cleanup was performed. Integrity ofthe tanks Is unknown but assumed to be poor. The suspicion of burled tankseast of the Ford Building was addressed by Inspection. The burled tank Isapparently an abandoned fuel oil tank which Is evidenced by typical filland vent pipes above ground. As part of the remedial actions evaluated Inthe FS, removal or sealing of these tanks was considered. Final remedialactions should Include some *tans of revving these tanks.

Page 2. Paragraph 1

No additional work was done to track the specific source of the conduitcontamination because such an effort would not have aided 1n determiningthe need or fora of a remedial action. Further, the RI did not Includetests to determine the occurrence and extent of utility contaarination.Based on the conduit observation and stor* sewer sampling, It was reason-able to assuee that all onslte utility piping and pipe bedding was contam-inated. A search and testing program for onslte burled utilities at anold, highly developed Industrial site such as Chen-Dyne could cost morethan the remedial actions which Include deep perimeter trenching (to locateand cutoff conduits exiting the site) and grouting both the conduit andsurrounding pipe bedding.

Page 2. Paragraph 2

The Ford Building was Investigated by an Inspection of all floors Includingconnecting utility tunnels In October 1983. The Final RI Report concludesa...1t Is reasonable to suspect that waste drums (from Cham-Dyne) may havebeen stored In the Ford Building". This 1s not a dismissal of possiblecontamination. It Is not necessary to have analytical data to make reason-able Judgements In the Feas1bl1ty Study on remedial actions for the Chem-Oynebuildings. Strong suspicion of building use (Ford) and visible spillage(garage) 1s sufficient to evaluate decontamination or demolition/disposal asremedial alternatives. Addltonal testing to confirm or refine remedial actions(such as decontamination) was Identified In the Final RI Report on page 3-126.

Page 3. Earagrapoh 3

Contaminants 1n the storm sewer sample Included the wastes known to have been

stored at Chem-Dyne, particularly In the northwest corner. The origin ofthese compunds 1s very likely contaminated Infiltration from Imperfectlysealed catch basins and subsurface Infiltration. The solution to storm setterreleases Involves eliminating or sealing the existing storn sewer and sealingthe sewer bedding materials. The solution does not require study of thedynamics of the entire storm sewer system. (Upstream drainage 1s accommodated1n the remedial solution of course.)

Page 2, Paragraph 3, last sentence

The purpose of the RI Is expressed on page 1-1 of the Final RI Report. Inshort, the RI 1s aimed at determining the need for and extent of remedial actionsat the site. The RI data Includes laboratory results and observations suchas soil types 1n test pits and soil borings, topography, and signs of chemicalspills. Decisions can be made without sampling and chemical analysis of everysuspicious area. For example, an extensive study of burled utilities Is notnecessary to decide, using storm sewer analysis and conduit observation, thatall utilities exiting the site will be cutoff and sealed. A major goal ofSuperfund Is to control the release of hazardous substances Into the environmentfrom abandoned waste sites. In part, the RI generates Information necessary forevaluation of the alternative control methods.

SOIL

Page 2. Paragraph 4

Site runoff 1s unlikely because the Chem-Dynt property 1s generally at alower elevation than surrounding property. Current site topography wasdetermined during the RI by aerial photography (flown November 21, 1983)methods. This "bowl" topography reduces the likelihood of site runoff fromaccumulated precipitation and Increases the tendency for percolation throughthe contaminated unsaturated zone. Both runoff and percolation are problems:which are addressed 1n the remedial actions evaluated In the FS. Overflowof the site by the Great Miami River and canal flooding Is also unlikelybecause of the flood control levees In the area which are designed for agreater than 100 year flood event.

The comments on site runoff are well taken. Site drainage Is a criticalIssue which Is addressed by remedial actions evaluated In the FS.

Page 3, Paragraph 1

Of the "offtlte" soil samples referenced, only two samples, OS-1 and OS-2,were considered "beckground" samples.

The other two samples. OS-3 and OS-4 Were taken 1 wed lately south of thewarehouse parking lot which had been used by Chem-Dyne to store druos;these saaples were taken to Investigate surface soils which were possiblycontaminated by parking lot runoff or direct spills. Samples OS-1 andOS-3 were taken fro* areas In the site vicinity which were not subject toor affected by site runoff or spills. Inorganic results of these samplesIs considered to be within the range of Inorganic composition for backgroundsoils In the art*.

Runoff fro* the warehouse parking lot was recognized as a factor which couldhave caused contamination of soils south of the lot. The topography mappresented In the TH for Subtask 3-6 In Volune 28 of 2 of the Final RI Reportshows the parking lot slope. This Is why OS-3 and OS-4 were taken and whythe site boundary was drawn to Include a portion of the soil south of theparking lot as well as the lot Itself.

Page 3, Paragraph 2

Cooaents on statistical methods applications to soil sampling schemes arewell taken. Statistics can be useful for evaluation of soil analysis data.However, the RI sampling and analysis program was constrained by practicallimits of laboratory capacity and cost.

As the comment on can appreciate, soil sampling at depths to almost 30 feeton a 20 acre site where contaminants can Include almost every prioritypollutant (and numerous nonprlorlty compunds) to achieve a high statisticallevel of confidence would require hundreds of soil saoples. For the purposeof remedial action alternative evaluation, this amount of work Is not necessary.

Within the real constraints on sample numbers, the decisions on soil saoplelocation were based on advice from OEPA (based on historical operations),aerial photography from 1976 to 1982, and visual signs of contamination.The sampling was biased toward areas of obvious or strongly suspected con-tamination. The goal of sampling was not to exhaustively characterize thecontamination but to develop enough Information to make reasonable decisionsregarding remedial actions.

The statistical connotation