RECORD OF DECISION

JOHN DEERE-OTTUMWA WORKS SITE

OTTUMWA, IOWA

Prepared by

U. S. ENVIRONMENTAL PROTECTION AGENCY

REGION VII

KANSAS CITY, KANSAS

SEPTEMBER 1991

S00057934SUPERFUND RECORDS

RECORD OF DECISION

DECLARATION

Declaration for the Record of Decision

John Deere-Ottumwa Works Site

Ottumwa, Iowa

Statement of Basis and Purpose

This decision document presents the selected remedial actionfor the John Deere-Ottumwa Works site in Ottumwa, Iowa. Theselected remedy was chosen in accordance with the requirements ofthe Comprehensive Environmental Response, Compensation, andLiability Act of 1980 (CERCLA), as amended by the SuperfundAmendments and Reauthorizatlon Act of 1986 (SARA) and theNational Oil and Hazardous Substances Pollution Contingency Plan(NCP). This decision document explains the factual and legalbasis for selecting the remedy for this site. The informationsupporting this remedial action decision is contained in theadministrative record for this site.

The State of Iowa concurs with the selected remedy.

Assessment of the Site

Actual or threatened releases of hazardous substances fromthis site, if not addressed by implementing the response actionselected in this Record of Decision (ROD), may present a currentor potential threat to public health, welfare, or theenvironment.

Description of the Selected Remedy

The principal threat at this site is posed by buried plant-generated waste material. Currently, the site is used forindustrial purposes only.

The major component of the selected remedy is the placementof deed restrictions, to run with the land, which provide formaintenance of an existing perimeter fence and which limit landuse.

Continued ground water and surface water monitoring willalso be required to ensure the selected remedy remains protectiveof human health and the environment.

Declaration of Statutory Determinations

The selected remedy is protective of human health and theenvironment, complies with federal and state requirements thatare legally applicable or relevant and appropriate to the

remedial action, and is cost-effective. This remedy utilizespermanent solutions and alternative treatment technologies, tothe maximum extent practicable for this site. However, theselected remedy does not reduce toxicity, mobility or volume ofthe site waste material through treatment, and therefore does notsatisfy the statutory preference for treatment as a principalelement of the remedial action. The site waste materials are notliquid, and are of low toxicity and low mobility. Treatment isnot practicable because it is not cost effective.

Because this remedy will result in hazardous substancesremaining on-site above health-based levels, and so not allow forunlimited use and unrestricted exposure at the site, a reviewwill be conducted within five years after commencement ofremedial action to ensure that the remedy continues to provideadequate protection of human health and the environment.

2 3Morris K^y ' DateRegional AdministratorUnited States Environmental Protection AgencyRegion VII

TABLE OP CONTENTS

DECLARATION

1.0 SITE BACKGROUND

1.1 SITE LOCATION AND DESCRIPTION1.2 SITE HISTORY AND ENFORCEMENT ACTIVITIES1.3 HIGHLIGHTS OF COMMUNITY PARTICIPATION

2.0 SCOPE AND ROLE OF RESPONSE ACTION WITHIN SITE STRATEGY

3.0 SUMMARY OF SITE CHARACTERISTICS

3.1 SOIL AND WASTE MATERIAL RESULTS

3.1.1 LANDFILL 13.1.2 LANDFILLS 2 AND 33.1.3 HAZARDOUS WASTE/DRUM STORAGE AREA3.1.4 OIL SPILL AREA3.1.5 SOUTH SCAR AREA

3.2 GROUND WATER RESULTS

3.3 SURFACE WATER AND SEDIMENT RESULTS

3.3.1 BLACK LAKE SURFACE WATER3.3.2 DRAINAGE DITCH AND BLACK LAKE SEDIMENT

4.0 SUMMARY OF SITE RISKS

4.1 OVERVIEW OF BASELINE RISK ASSESSMENT4.2 INDICATOR COMPOUNDS4.3 EXPOSURE ASSESSMENT4.4 TOXICITY ASSESSMENT4.5 RISK CHARACTERIZATION

4.5.1 RISKS FROM CARCINOGENIC COMPOUNDS4.5.2 RISKS FROM NON-CARCINOGENIC COMPOUNDS4.5.3 RISKS FROM LEAD4.5.4 ENVIRONMENTAL EVALUATION

4.5.4.1 BLACK LAKE SURFACE WATER4.5.4.2 BLACK LAKE SEDIMENTS4.5.4.3 TERRESTRIAL RISK

4.5.5 CONCLUSION

4.6 REMEDIATION GOALS

5.0 DESCRIPTION OF ALTERNATIVES

5.1 GROUND WATER

5.1.1 NO-ACTION WITH CONTINUED GROUND WATER MONITORING

5.2 SURFACE WATER AND SEDIMENTS

5.2.1 NO-ACTION

5.3 SOIL/WASTE MATERIAL

5.3.1 ALTERNATIVE 1: NO-ACTION5.3.2 ALTERNATIVE 2: INSTITUTIONAL CONTROLS5.3.3 ALTERNATIVE 3: CONCRETE CAP AND INSTITUTIONAL

CONTROLS5.3.4 ALTERNATIVE 4: IN-SITU STABILIZATION/SOLIDIFICATION

WITH CONCRETE CAP AND INSTITUTIONALCONTROLS

6.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES

6.1 OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT6.2 COMPLIANCE WITH ARARS6.3 LONG-TERM EFFECTIVENESS AND PERMANENCE6.4 REDUCTION OF TOXICITY, MOBILITY, OR VOLUME6.5 SHORT-TERM EFFECTIVENESS6.6 IMPLEMENTABILITY6.7 COST6.8 STATE ACCEPTANCE6.9 COMMUNITY ACCEPTANCE

7.0 SELECTED REMEDY

7.1 GROUND WATER, SURFACE WATER, AND SEDIMENTS7.2 SOILS/WASTE MATERIAL

8.0 STATUTORY DETERMINATIONS

8.1 PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT8.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE

REQUIREMENTS8.3 COST-EFFECTIVENESS8.4 UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVE

TREATMENT TECHNOLOGIES TO THE MAXIMUM EXTENT PRACTICABLE8.5 PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT

9.0 DOCUMENTATION OF SIGNIFICANT CHANGES

ATTACHMENTS

ATTACHMENT A - RESPONSIVENESS SUMMARY

ATTACHMENT B - FIGURES

Figure 1 Site Location MapFigure 2 Site Features MapFigure 3 Soil Boring and Sediment Sampling LocationsFigure 4 Monitoring Well, Piezometer and Surface Water

Gaging LocationsFigure 5 Estimated Lateral Extent of Fill

ATTACHMENT C - TABLES

Table 1 Occurrence of Constituents in Phase IIUnfiltered Ground Water Samples

Table 2 Occurrence of Constituents in Surface Waterand Sediment From Black Lake

Table 3 Occurrence of Constituents in Drainage DitchSediment Samples

Table 4 Occurrence of Constituents in Landfill 1,Subsurface Material Samples

Table 5 Occurrence of Constituents in Landfills 2 and3, Subsurface and Composite Material Samples

Table 6 Occurrence of Constituents in Drum Storage/Hazardous Waste Storage Area, SurficialMaterial Samples

Table 7 Occurrence of Constituents in Drum Storage/Hazardous Waste Storage Area, SubsurfaceSamples

Table 8 Occurrence of Constituents in Oil Spill Area,Surficial Soil Samples

Table 9 Occurrence of Constituents in Oil Spill Area,Subsurface Soil Samples

Table 10 Occurrence of Constituents in South Scar Area,Surficial Soil Samples

Table 11 Occurrence of Constituents in South Scar Area,Subsurface Soil Samples

Table 12 Indicator Compounds Used in Risk AssessmentCalculations

Table 13 Reference Doses, and Cancer Slope Factors forIndicator Compounds

Table 14 Potable Ground Water Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks

Table 15 Current Site Worker Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe Drum Storage/Hazardous Waste Storage Area

Table 16 Current Site Worker Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe Oil Spill Area

Table 17 Current Site Worker Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe South Scar Area

Table 18 Future Site Worker Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inLandfill 1

Table 19 Future Site Worker Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inLandfills 2 and 3

Table 20 Adult Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe Drum Storage/Hazardous Waste Storage Area

Table 21 Adult Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe Oil Spill Area

Table 22 Adult Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe South Scar Area

Table 23 Adult Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inLandfill 1

Table 24 Adult Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inLandfills 2 and 3

Table 25 Child Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe Drum Storage/Hazardous Waste Storage Area

Table 26 Child Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe Oil Spill Area

Table 27 Child Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inthe South Scar Area

Table 28 Child Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inLandfill 1

Table 29 Child Resident Exposure Doses, HazardQuotients, and Excess Lifetime Cancer Risks inLandfills 2 and 3

Table 30 Potable Surface Water Exposure Dose and HazardQuotient

Table 31 Calculated Blood Lead Levels in Children

ATTACHMENT D - GLOSSARY OF EVALUATION CRITERIA

ATTACHMENT E - STATE LETTER OF CONCURRENCE

RECORD OF DECISION

DECISION SUMMARY

1.0 SITE BACKGROUND

1.1 SITE LOCATION AND DESCRIPTION

The John Deere-ottumwa Works site is located in Ottumwa, acity of approximately 27,000 people, in Wapello County, Iowa. Asite location map, Figure 1, is attached.

The site occupies approximately 105 acres. It is bounded bythe Wabash Railroad tracks on the west with Madison Avenue locatedimmediately west of the railroad. Highway 63/34 bounds the siteon the east and Vine Street forms the northern boundary. Theentire site is enclosed by a eight foot high chain link fencetopped with barbed wire, except for an area on the southeastcorner where the right-of-way for Highway 63/34 is located. Thesouthern boundary of the site is defined by the location of thisfence. Adjacent property to the north, south, and west is usedfor residential purposes. Deere & Company is an active facilityand currently manufactures and assembles agricultural equipment atthe site.

A single disposal area of approximately 20 acres has beendetermined to exist on-site with the depth of waste materialranging between four and 10 feet deep. Waste material consists ofamber to black colored friable sand and vitrified greenish-yellowmaterial with pieces of wood and coal, metal fragments, and paintchips. Approximately 90% of the landfill area is currentlycovered with buildings or pavement.

The primary contaminants at the John Deere-ottumwa Works sitehave been determined to be the metals arsenic, cadmium, chromium,and lead as well as semi-volatile polynuclear aromatichydrocarbons (PAHs).

The site is located within the Des Moines River flood plainand is approximately 1,000 feet southwest of the river. Floodwater periodically inundated the site until 1955 when a series ofdikes were constructed to control river levels. The alluvialaquifer in the vicinity of the site is classified as IIB, apotential source of drinking water. Topography of the site isessentially flat. A wetland is located across the Des MoinesRiver from the site and is unaffected by site contaminants.Approximately 150 feet east of the northern portion of the site isBlack Lake, one of the secondary sources of drinking water for theCity of Ottumwa, and as such falls within Iowa Class C, drinkingwater sources. Black Lake is used only intermittently when theprimary source, the Des Moines River, cannot provide all of themunicipal water supply needs for the City of Ottumwa. Totalannual withdrawal from Black Lake for use in the Ottumwa watersupply is normally 15 to 30 million gallons.

Immediately underlying the site are approximately 13 to 26feet of alluvial deposits consisting primarily of unconsolidatedsilty clay, silty sand, sand, and gravel. Ground water in the

alluvial aquifer flows in a generally east-northeasterly directiontoward the Des Moines River. Underlying the sand and gravel is ashale unit of approximately 100 to 150 feet in thickness. Thisshale unit is not a major source of ground water in the areabecause of its impermeable nature.

1.2 SITE HISTORY AND ENFORCEMENT ACTIVITIES

From 1911 to 1973, Deere & Company disposed of plantgenerated waste on-site by burying the wastes in the shallowalluvium. Wastes buried on-site include solvents, paint sludges,heat treating cyanide, heat treating sludges, petroleumdistillates and foundry sand. After placement on the land, someof the waste material was burned on a regular basis.

In 1965, Deere & Company purchased what is now thesouthwestern portion of the site. Prior to Deere & Companyacquiring this additional property, it had been used as a salvageyard. An oily coating on the ground surface within parts of thispiece of property existed at the time of purchase by Deere &Company. A single building exists today from the salvageoperation and is used by Deere & Company for storage.

Deere & Company granted a right of way easement of a portionof their property to Iowa Department of Transportation (IDOT) forconstruction of Highway 63/34. Based on historical aerial photosand soil borings completed during the RI, it appears likely that aportion of the area called Landfill 1 which contains wastematerial extends onto what is now IDOT right of way, whichencompasses approximately 8.3 acres.

In May 1985, the EPA conducted a Site Investigation (SI) atthe site. Analysis of soil and sediment sample collected duringthe investigation showed elevated levels of metals and organics insamples collected in the vicinity of the drum and hazardous wastestorage area and from the drainage ditch adjacent to Deere &Company property.

Based upon SI data, the site was evaluated for possibleinclusion on the National Priorities List (NPL) by completing aHazard Ranking Scoring (HRS). An HRS score of 42.32 was assignedto the John Deere-Ottumwa Works site (a score of 28.5 issufficient to place a site on the NPL). The NPL is a nationwidelist of sites that, due to site conditions and contaminants, havebeen made priorities for remedial evaluation and response, ifnecessary. EPA proposed the site for listing in June 1988 and itbecame final on the NPL in February 1990.

On September 20, 1989, EPA and Deere & Company entered intoan Administrative Order on Consent. The order required Deere &Company to perform a Remedial Investigation (RI) for the purposeof determining the nature and extent of any contamination existingon-site by conducting a field investigation. In addition, theorder required a Feasibility Study (FS) to be performed,

evaluating a range of appropriate alternatives to addresscontaminants identified during the field investigation. EPAreviewed and approved plans detailing work to be conducted byDeere & Company in fulfilling terms of the order. EPA alsoprovided oversight of RI field activities conducted by Deere &Company.

Deere & Company contracted with Geraghty & Miller, Inc. toconduct field sampling at the site and to incorporate theinvestigation results into RI and FS Reports. The fieldinvestigation was completed in November 1990. The final RI and FSReports were completed in July 1991 and approved by EPA inconsultation with IDNR.

1.3 HIGHLIGHTS OF COMMUNITY PARTICIPATION

The RI and FS Reports and the Proposed Plan for the JohnDeere-Ottumwa Works site were released to the public for commentas required by CERCLA Section 113(k)(2)(b)(I-V) and Section 117.The public comment period was from July 20, 1991 to August 19,1991. These two documents were made available to the public withthe administrative record, which is located at the Ottumwa PublicLibrary and at the EPA Region VII office. The notice ofavailability for these documents was published in the OttumwaCourier on July 13, 1991. A public meeting was held on August 8,1991 in Ottumwa, Iowa. At this meeting, representatives from EPA,the State of Iowa, the Iowa Department of Public Health, and theAgency for Toxic Substances and Disease Registry (ATSDR) wereavailable to answer questions about problems at the site and theremedial alternatives under consideration. Comments receivedduring the comment period and EPA responses to the commentscomprise the Responsiveness Summary, which is attached hereto asAppendix D. The decision for this site is based on theAdministrative Record, which includes the Responsiveness Summary.

2.0 SCOPE AND ROLE OF RESPONSE ACTION WITHIN SITE STRATEGY

The response activities described in the Decision Summaryaddress all contaminants known at the site and are intended toconstitute final action for this site.

3.0 SUMMARY OF SITE CHARACTERISTICS

The nature and extent of contamination at the John Deere-Ottumwa Works site is summarized below. This summary is basedprimarily on data generated by the work performed by Deere &Company in May through November 1990, and in the RI. An in-depthdiscussion of the nature and extent of contamination characterizedduring the RI may be found in the RI Report which is contained inthe administrative record. Tabulated analytical results from theRI may be found in Tables 1 through 11, attached. Background .pa

levels of site related contaminants are also presented in Tables 1through 11.

During the RI, Geraghty & Miller, technical contractor forDeere & Company, characterized the nature and extent of wastematerial and investigated the effects the presence of wastematerial at the site has had on ground water, surface water, andsediments. The discussion of these findings are divided intothree main media: soils and waste material, ground water, andsurface water and sediments. Soils and waste materials arefurther divided into five areas of initial concern: Landfill 1,Landfills 2 and 3, Hazardous Waste/Drum Storage Area, Oil SpillArea, and the South Scar Area. A site map displaying the variousareas of concern is presented in Figure 2, attached. Figure 3displays soil boring and sediment sampling locations and Figure 4displays monitoring well, piezometer, and surface water samplelocations.

The primary contaminants at the John Deere-Ottumwa Works sitehave been determined to be the metals arsenic, cadmium, chromium,and lead as well as semi-volatile polynuclear aromatichydrocarbons (PAHs).

3.1 SOIL AND WASTE MATERIAL RESULTS

Prior to the RI, several separate former disposal areas werethought to exist on-site: Landfill 1, Landfills 2 and 3 which areadjacent to each other, and the South Scar Area. Soil/waste(hereafter called soil) boring sample analysis and visualobservation of soil, monitoring well, and piezometer boringmaterials provided information necessary to redefine the extent ofthese waste disposal areas. Figure 5 shows the general boundaryof what is now known to be a more extensive single disposal areaof approximately 20 acres. A majority of the northeast quadrant(shaded area on Figure 5) of the site contains plant generatedwaste at depths ranging from 4 to 10 feet below ground surface.The extreme northeastern area of the site was apparently used fordisposal in the early years of plant operation, which wasdiscontinued when this lower-lying area became built up and Deere& Company reguired additional buildings for its plant operations.Subsequently, numerous buildings have been constructed over theformer disposal area. Currently, approximately 90% of thelandfill area is covered with buildings or pavement.

Waste materials identified in the areas on-site known asLandfill 1 and Landfills 2 and 3 consist of amber to black coloredfriable sand and vitrified greenish-yellow material with pieces ofwood and coal, metal fragments, and paint chips.

Metals concentrations in on-site waste material are elevatedrelative to on-site background soil metals levels. Acetone andmethylene chloride were detected a number of times in wastematerial samples and acetone was detected three times in ground

water samples. Both acetone and methylene chloride are consideredsite related contaminants.

3.1.1 LANDFILL 1

Subsurface soil and waste sample results from Landfill 1indicate the presence of low levels of two volatile organiccompounds, acetone and tetrachloroethene, and ten semi-volatileorganics including up to 19,000 parts per billion (ppb) totalcarcinogenic polynuclear aromatic hydocarbons (PAHs) and 25,600ppb total (carcinogenic and non-carcinogenic) PAHs. Variousinorganic compounds were detected above background levelsincluding arsenic, beryllium, and lead at levels up to 26 partsper million (ppm), 3.0 ppm, and 810 ppm, respectively.

No shallow soil samples were collected from the Landfill 1because it is covered with concrete and gravel.

3.1.2 LANDFILLS 2 AND 3

Subsurface soil and waste sample results from Landfills 2and 3 indicate the presence of low levels of four volatiles,acetone, methylene chloride, toluene, and xylene, and sixteensemi-volatiles including up to 5,000 ppb total carcinogenic PAHsand up to 84,500 ppb total PAHs. Various metals were detectedabove background levels including beryllium and lead at levels upto 2.0 ppm and 150 ppm, respectively.

No shallow soil samples were collected from the Landfills 2and 3 because they are covered with either concrete or gravel.

3.1.3 HAZARDOUS WASTE/DRUM STORAGE AREA

The hazardous waste/drum storage area is currently used byDeere & Company to store new materials for use in productionoperations and to store waste materials while waiting for off-sitedisposal. Deere & Company is a Resource Conservation and RecoveryAct (RCRA) waste generator and may store waste materials for aperiod not to exceed ninety (90) days.

Subsurface soil and waste sample results from the HazardousWaste/Drum Storage Area indicate the presence of two low levelvolatiles, acetone and methylene chloride, and five semi-volatiles including up to 560 ppb total carcinogenic PAHs and1,280 ppb total PAHs. Various metals were detected abovebackground levels including lead at levels up to 77 ppm.

Shallow (0-2 foot depth) soil sample results from theHazardous Waste/Drum Storage Area showed a single occurrence ofacetone at a low level and six semi-volatiles including up to 470ppb total carcinogenic PAHs and 1,330 ppb total PAHs. Variousmetals were detected above background levels including lead atlevels up to 350 ppm.

3.1.4 OIL SPILL AREA

Subsurface soil and waste sample results from the Oil SpillArea show the presence of two low level volatiles, acetone andtoluene. No semi-volatiles were detected and no metals weredetected above background levels with the exception of aluminum atlevels up to 7,500 ppm.

Shallow soil sample results from the Oil Spill Area indicatethat no elevated levels of organic compounds were detected.Various metals were detected above background levels includingberyllium at levels up to 1.9 ppm and zinc up to 860 ppm.

The oily coating which was observed in this area during the1985 Site Investigation, was not detected during the RI and nowaste material such as has been identified in the northeastportion of the site was found.

3.1.5 SOUTH SCAR AREA

Subsurface soil and waste sample results from the South ScarArea show the presence of two low level volatiles, acetone andxylene, and a single occurrence of the semi-volatile naphthaleneat 1200 ppb. Various metals were detected above background levelsincluding copper at levels up to 24 ppm and zinc up to 85 ppm.

Shallow soil sample results from the South Scar Areaindicate the presence of two low level volatiles, acetone andtetrachloroethene. Various metals were detected above backgroundlevels including lead at levels up to 80 ppm.

The South Scar Area boring samples did not contain wastematerial as was identified in the northeast portion of the site.The top two feet, below the vegetative cover, did containconstruction-type rubble such as bricks and concrete.

3.2 GROUND WATER RESULTS

Two rounds of ground water samples were analyzed from on-siteand downgradient off-site monitoring wells. These two rounds ofsamples were collected under Phase I and Phase II of the RI fieldwork. Phase I samples were collected after a limited amount ofwell purging (pumping), producing very turbid samples from thealluvial aquifer. Phase II samples were collected after much moreextensive purging efforts. The resulting samples wereconsiderably clearer than Phase I samples.

The metals arsenic, cadmium, chromium, and lead pose theprincipal threat to ground water at the John Deere-Ottumwa Workssite.

Acetone, at 48 ppb in monitoring well 11 (MW 11), was theonly volatile detected in ground water during the first phase ofsampling. A total of six volatiles were detected in Phase II

samples including 1,2-dichloroethane and benezene found at 3 ppband 2 ppb, respectively in MW 4 which is down gradient from theSouth Scar Area. Five of the six volatiles detected are commonconstituents of petroleum fuels and were found in monitoring wells4, 5, and 6, downgradient from the South Scar Area and in MW 3,directly northeast of the South Scar Area. The highestconcentration of these petroleum related contaminants was 41 ppb.The remaining volatile detected in Phase II samples was acetone at2 ppb and 48 ppb in MW 8, located adjacent to Landfills 2 and 3,and MW 11, located in the Hazardous Waste/Drum Storage Area,respectively.

No semi-volatiles were detected in Phase I ground watersamples although three compounds were detected in Phase IIsamples at levels up to 4 ppb in MW 1 and piezometer 2 (PZ 2),downgradient from Landfill 1 and the Hazardous Waste/Drum StorageArea, respectively. Two of the three semi-volatiles, bis(2-ethylhexyl)phthalate and di-n-butyl phthalate, detected in groundwater are ubiquitous common laboratory contaminants and were notdetected in EPA's split samples. No PAHs were detected in groundwater. Piezometer 2 was not sampled during Phase I activities.

Various metals were detected above Maximum Contaminant Levels(MCLs) in Phase I samples including arsenic, barium, cadmium,chromium, and lead. Monitoring wells 5 and 6, locateddowngradient from the South Scar area, contained the highestconcentrations of arsenic (0.37 ppm), barium (13 ppm), andchromium (0.24 ppm) detected at the site. The highest level oflead (0.48 ppm) was detected in MW 7, adjacent to Landfills 2 and3. Other monitoring well locations with relatively high levels oftotal metals in Phase I samples are the Oily Spill Area and theHazardous Waste/Drum Storage Area.

Two metals of potential concern were detected in Phase IIground water samples at elevated levels. Barium and lead wereeach detected at only one monitoring well location. Barium wasfound at 1.1 ppm in MW 11, located in the Hazardous Waste StorageArea. Lead was found at 0.093 ppm in PZ 2, located downgradientfrom the Hazardous Waste/Drum Storage Area.

Turbidity measurements were performed on Phase II groundwater samples with results indicating that the clearer Phase IIsamples were, in general, one to two orders of magnitude (ten to100 times) greater than EPA's Maximum Contaminant Level (MCL) forturbidity applied to surface drinking water supplies. Turbidground water samples potentially contain not only contaminantsource metals but also naturally occurring metals.

Naturally occurring metals are often physically associatedwith fine-grained clay and silt sediments found in alluvialaguifers. Ground water samples collected from monitoring wellsthat are pumped infrequently often contain such sediments,producing turbid samples. When total metals analyses areconducted on turbid ground water samples, naturally occurring

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metals may inadvertently be measured along with any metals thatmay be due to the presence of waste material.

Because the monitoring wells were purged extensively priorto collection of Phase II ground water samples, these sampleswere considerably clearer than Phase I samples and so Phase IIresults showed a marked decrease in metals concentrations.Considering the potential effect of turbid samples, the highermetals concentrations in Phase I samples are consistent with, andverify, the metals results from Phase II samples. Because of theturbidity in Phase I samples, Phase II data is more representativeof dissolved metals concentrations that may move along with theground water and so potentially be found in drinking waterproduced from the alluvial aquifer. For this reason, Phase IIground water results were used in risk assessment calculations.

To assure adequate protection of human health and theenvironment, continued ground water monitoring at the site isrequired.

3.3 SURFACE WATER AND SEDIMENT RESULTS

3.3.1 BLACK LAKE SURFACE WATER

Black Lake surface water was sampled and found to contain nohazardous organic compounds, but three metals of potentialinterest, barium (0.43 ppm), manganese (0.15 ppm), and zinc (0.038ppm), although none above EPA's Maximum Contaminant Levels (MCLs)established for drinking water supplies.

3.3.2 DRAINAGE DITCH AND BLACK LAKE SEDIMENT

Sediment samples were collected from the drainage ditchbetween the site and Highway 63/34, which drains surface waterfrom the eastern portion of the site, and from the southern edgeof Black Lake near a culvert outlet. During times of highrainfall, the culvert may allow site surface water to reach BlackLake.

No hazardous organic compounds were detected in the drainageditch or Black Lake sediments. Elevated levels of copper, lead,and selenium were detected in the upgradient (background) drainageditch sample. Downgradient drainage ditch samples exhibiteddecreased levels of these constituents. Black Lake sedimentcontained several inorganics of potential interest; arsenic (0.64ppm), barium (8.7 ppm), cadmium (1.2 ppm), chromium (3.5 ppm), andnickel (8.5 ppm).

4.0 SUMMARY OF SITE RISKS

4.1 OVERVIEW OF BASELINE RISK ASSESSMENT

A Baseline Risk Assessment is an evaluation of the potentialthreat to human health and the environment in the absence of anyremedial action. It provides information to help EPA determinewhether remedial action is necessary at a site. A Baseline RiskAssessment was conducted for this site to determine the potentialeffects on human health and the environment. In this evaluation,both current and future land-use scenarios were evaluated. Thecomplete Baseline Risk Assessment is presented in the RI Reportwhich is available in the administrative record.

4.2 INDICATOR COMPOUNDS

A total of 19 chemicals plus PAHs were identified in theBaseline Risk Assessment to be of potential concern. Toxicityinformation was evaluated for all chemicals of concern including,where applicable, cancer potency factors and noncarcinogeniceffects. Cumulative effects from all contaminants available foruptake were evaluated for each pathway. Contaminants of concernare contaminants that have been detected at the site, haveinherent toxic or carcinogenic effects, and are likely to pose thegreatest concern with respect to the protection of human healthand the environment. The compounds selected include the moremobile and persistent chemicals at the site, as well as thosepresent at the highest concentrations. These indicator compoundsare listed in Table 12.

4.3 EXPOSURE ASSESSMENT

The exposure assessment identified potential pathways androutes for contaminants of concern to reach the receptors as wellas the estimated contaminant concentration at the points ofexposure. Pathways by which humans could be exposed, both on-siteand off-site, to the chemicals of concern were evaluated based onreasonable assumptions about current and future land uses. Thefollowing pathways were evaluated:

1) Exposure of on-site workers to contaminatedsoil/waste through dermal contact, inhalation, and ingestion;

2) Exposure of on-site workers in the future by dermalcontact, ingestion, and inhalation of subsurface soil/wastecurrently covered by concrete pads or buildings;

3) Exposure of potential on-site residents (childrenand adults) in the future to contaminated soil/waste throughdermal contact, inhalation, and ingestion;

4) Exposure of on-site and off-site residents in thefuture through ingestion and inhalation of contaminated groundwater used as a primary potable water source;

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5) Exposure of on-site and off-site residents in thefuture through ingestion and inhalation of Black Lake surfacewater used as a primary potable water source;

6) Exposure of local residents, through ingestion, tofish caught from Black Lake;

4.4 TOXICITY ASSESSMENT

Reference doses (RfDs) have been developed by EPA forindicating the potential for adverse effects from exposure tochemicals exhibiting noncarcinogenic effects. RfDs, which areexpressed in units of mg/kg/day (parts per million/day), areestimates of lifetime daily exposure levels for humans that arelikely to be without appreciable risk of adverse health effects.Estimated intakes of chemicals from environmental media (e.g., theamount of a chemical ingested from contaminated drinking water)can be compared to the RfD. The RfDs applicable at the JohnDeere-Ottumwa Works site are listed in Table 13.

Cancer potency factors (CPFs) or slope factors (SF) have beendeveloped for estimating excess lifetime cancer risks associatedwith exposure to potentially carcinogenic chemicals. SFs, whichare also expressed in units of mg/kg/day (parts per million/day),are multiplied by the estimated intake of a potential carcinogento provide an upper-bound estimate of the excess lifetime cancerrisk associated with exposure at that intake level. The term"upper-bound" reflects the conservative estimate of the riskscalculated from the SF. Use of this approach makesunderestimation of the actual cancer risk highly unlikely. TheSFs applicable to the John Deere-Ottumwa Works site are listed inTable 13.

4.5 RISK CHARACTERIZATION

The risk characterization quantifies present and potentialfuture risk to human health that may result from exposure to thecontaminants of concern found at the site. The site-specific riskvalues are estimated by incorporating information from thetoxicity and exposure assessments.

Two quantitative evaluations are made: the incremental riskto the individual resulting from exposure to a carcinogen; or, fornon-carcinogens, a numerical index or ratio of the exposure doselevel to an acceptable reference dose.

4.5.1 RISKS FROM CARCINOGENIC COMPOUNDS

For carcinogens or suspected carcinogens, a quantitative riskassessment involves calculating risk levels considered torepresent the probability or range of probabilities of developingadditional incidences of cancer under the prescribed exposureconditions. Carcinogenic risk estimates, expressed as additional

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incidences of cancer, are determined by multiplying the cancerpotency by the projected exposure dose level. It is thecarcinogenic potency factor, expressed in (mg/kg/day)~ whichconverts the estimated exposure dose level, expressed inmg/kg/day, to incremental risk. These risks are probabilitiesthat are generally expressed in scientific notation (e.g.,1 x 10~6).

An excess lifetime cancer risk of 1 x 10~6 indicates that, asa plausible upper bound, an individual has a one in one millionchance of developing cancer as a result of site-related exposureto a carcinogen over a 70-year lifetime under the specificexposure conditions at the site. A cancer risk level of 1 x 10means that an individual has an estimated excess cancer risk ofone in ten thousand when exposed to a given concentration over alifetime. These risk estimates are based on upper bound values,and are likely to be lower, possibly even zero. The EPA generallyconsiders risk levels of 10 or lower to be acceptable.

The carcinogenic risks were calculated for pathways 1, 2, 3,and 4. Carcinogenic risk was not calculated for pathways 5 and 6because no carcinogenic compounds were present for exposurethrough these routes. Carcinogenic risks calculated range between1 x 10~5 and 3 x 10 , as shown in Tables 14 through 30.

The Baseline Risk Assessment indicated that there are no siterelated compounds that present a potentially unacceptable cancerrisk level.

4.5.2 RISKS FROM NON-CARCINOGENIC COMPOUNDS

Estimations of risk associated with exposure to non-carcinogenic compounds employ a slightly different procedure. TheEPA has developed standards, guidelines, and criteria that providelevels of intakes considered to protect human populations frompossible adverse effects resulting from chemical exposures. Aratio of the estimated chemical intake derived from thecontaminant concentration in a given medium to the contaminant'sReference Dose (RED) provides a numerical measure of the potentialthat adverse health effects may result. This ratio is referred toas the chronic hazard quotient (HQ). By adding the HQs for allcontaminants within a medium or across all media to which a givenpopulation may reasonably be exposed, the Hazard Index (HI) can begenerated.

In general, an HI value of one (1) or greater indicates thatsome risk of noncarcinogenic health effects exist with these risksincreasing proportionally to the HI value.

A Hazard Index was calculated for each pathway evaluated.The HI value calculated for each pathway was equal to or less than1, indicating no anticipated noncarcinogenic risks, with theexception of pathway 3 for children, as shown in Tables 14 through30. The HI value associated with potential exposure of children,

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who in the future, might reside on-site and come in contact withcontaminated soil/waste is slightly above 1, which means anoncarcinogenic risk exists which must be addressed by this ROD.Currently, neither children nor adults reside on-site.

4.5.3 RISKS FROM LEAD

Lead is also a carcinogen but EPA believes that toxic effectsfor sensitive populations will occur at lower levels than thosewhich will produce carcinogenic effects. The EPA has establisheda unique procedure for evaluating risk due to exposure to lead,which is a compound of concern at the site. The EPA has developedthe Uptake/Biokinetic (UBK) model to estimate blood lead levelsresulting from exposures to lead. The EPA has established 10micrograms of lead per deciliter (ug/dL) as a blood level inchildren which is unlikely to result in adverse health effects.Levels above 10 ug/dL are believed to result in adverseneurobehavioral effects in exposed children.

Mean blood levels predicted by the UBK model are presented inTable 31. Blood lead levels of hypothetical children who may, inthe future, be exposed to site contaminants by direct contact withwaste material, inhalation of site-generated dust, and site groundwater range up to 4.59 ug/dL. This level is well below theaccepted standard of 10 ug/dL, indicating no adverse healtheffects are expected due to site-related lead concentrations.

4.5.4 ENVIRONMENTAL RISKS

Environmental and ecological risks, including potential risksto critical habitats and endangered species and endangered specieshabitats, associated with the presence of contamination at thesite were also considered as part of the risk assessment. No suchrisks were identified.

4.5.4.1 BLACK LAKE SURFACE WATER

Two constituents of concern were detected in the Black Lakewater sample: barium and zinc. The soluble barium concentrationwould likely have to exceed 50 ppm before adverse effects toaquatic life would be expected. The reported barium concentrationof 0.43 ppm suggests that the potential for barium to impactaquatic life in Black Lake is very low. The detectedconcentration of zinc, 0.038 ppm, is less than the Class B IowaWater Quality Criteria of O.lOppm (Black Lake falls within ClassC, drinking water sources).

4.5.4.2 BLACK LAKE SEDIMENT

No hazardous organic compounds were detected in sedimentcollected from Black Lake. A comparison of the reported sedimentmetal concentrations with the background soil concentrationsindicate that the concentrations are similar to background values.

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The sediment metal data suggest that the site is not acting as asignificant release source for sediment-bound metals.

4.5.4.3 TERRESTRIAL RISK

The John Deere-Ottumwa Works facility has been used forequipment manufacturing since the early 1900s and so does notprovide suitable habitat to support a complex terrestrialecosystem. The site has not been identified as a critical habitatfor any species. Historical records report sightings of four rareand threatened or endangered species in the Ottumwa area:Graham's Watersnake (Reaina grahami). piping plover (Charadriusmelodus), woodland vole (Microtus pinetorum), and the southern boglemming (Synaptomys cooperi). Ottumwa is also a wintering groundfor the bald eagle (Haliaeetus leucocephalus) and roosts arelocated several miles downstream on the Des Moines River.

RI sample results have indicated that waste material iseither buried or covered with buildings or pavement and little tono migration of site related contaminants has occurred. Potentialexposures to threatened or endangered species are considered to below and no greater than those estimated for the aguatic andterrestrial ecosystems.

4.5.5 CONCLUSION

In conclusion, based on the results of the risk assessment,EPA has determined that actual or threatened releases of hazardoussubstances from this site, if not addressed by implementing theresponse action selected in this ROD, may present a current orpotential threat to public health, welfare, or the environment.

4.6 REMEDIATION GOALS

Federal and state cleanup standards for the contaminants ofconcern in soil have not been established at this time. The goalof any remedial action is to prevent unacceptable risks to humanhealth and the environment from occurring due to the presence ofsite related contaminants. This may be accomplished by one of twomeans: removing and/or treating contaminated material to reducecontaminant concentrations or by breaking exposure pathways toprevent unacceptable exposures of sensitive populations fromoccurring.

The EPA has determined that implementing institutionalcontrols to prevent children from being exposed to on-sitecontaminants is adequate to address health concerns at the JohnDeere-Ottumwa Works site, by breaking the exposure pathway.

5.0 DESCRIPTION OF ALTERNATIVES

The alternatives that were evaluated in detail in theFeasibility Study (FS) are described in this section. Four

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alternatives were determined to be appropriate for considerationat this site. These alternatives provided a range of variousremedial alternatives. The following descriptions summarize thealternatives, including their treatment components, implementationrequirements, estimated costs, and estimated time for completion.The three media potentially affected by the site, as discussed insection 3.0, ground water, soil/waste material, and surface waterand sediments are further addressed below.

5.1 GROUND WATER

The Baseline Risk Assessment indicated that ground watercontamination does not pose a significant threat to human healthor the environment, therefore only the "no-action" alternative isdescribed below.

5.1.1 NO-ACTION (WITH CONTINUED GROUND WATER MONITORING)

This alternative involves no action at the site to preventor reduce exposures to potentially contaminated ground water.There are no costs associated with this alternative.

However, EPA will require that continued ground watermonitoring would be conducted to ensure that no unacceptableexposure to risks posed by conditions at the site occur in thefuture. Ground water and surface water samples would be collectedon a regular basis from existing monitoring wells on-site and off-site and from Black Lake unless new information is obtained whichindicates that additional monitoring locations are necessary toproperly evaluate site contaminants in ground water and surfacewater. Samples would be analyzed for volatile organic, semi-volatile organics, and metals.

The total present worth cost of continued collection andanalysis of ground water samples, assuming a periodic monitoringprogram over five years, is estimated to be approximately $99,600.

There are no federal or state ARARs for the no-actionalternative. Compliance with federal and state ARARs is notrequired because no remedial action is necessary to protect humanhealth or the environment.

5.2 SURFACE WATER AND SEDIMENT

Data collected during the RI and the Baseline Risk Assessmentindicate that surface water and sediments do not pose asignificant threat to human health or the environment, therefore,only the "no-action" alternative is described below.

5.2.1 NO-ACTION (WITH ADDITIONAL SURFACE WATER MONITORING)

This alternative involves no action at the site to prevent orreduce exposures to potentially contaminated surface water andsediments. There are no costs associated with this alternative.

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However, EPA will require that surface water samples fromBlack Lake be collected and analyzed in addition to ground watersamples as discussed above in Section 5.1.1.

There are no federal or state ARARs for the no-actionalternative. Compliance with federal and state ARARs is notrequired because no remedial action is necessary to protect humanhealth or the environment.

5.3 SOIL/WASTE MATERIAL

The Baseline Risk Assessment indicated a potentialnoncarcinogenic health threat to children from site soil/wastematerial if the site were allowed to be used for residentialpurposes in the future. Therefore, a range of alternatives wasevaluated as described below.

5.3.1 ALTERNATIVE 1: NO-ACTION

The National Contingency Plan (NCP) requires that the no-action alternative be evaluated for every site. This alternativeinvolves no action at the site to prevent or reduce exposures tosite waste material. There would be no costs associated with thisalternative.

5.3.2 ALTERNATIVE 2: INSTITUTIONAL CONTROLS

This alternative would include implementation of deedrestrictions to run with the land which limit access and land usefor both the Deere & Company property and the right-of-way forHighway 63/34. The restrictions would require continuedmaintenance of the existing eight foot site perimeter fence toppedwith barbed wire to restrict unauthorized public access, and wouldlimit future use of the site to prevent residential development ofthe property or other similar exposure situations (e.g., schoolbuilding, preschool).

A maintenance program for the existing peripheral fence iscurrently being carried out by Deere & Company. Deed restrictionsare easily implemented by filing such deed restrictions with localgovernment officials.

The total present worth cost of implementing alternative 2 isassociated with lodging the deed restrictions and is estimated tobe approximately $4,000. The cost of maintaining the perimeterfence is currently covered by the facility's operating budget andso would require no additional funds.

5.3.3 ALTERNATIVE 3: CONCRETE CAP AND INSTITUTIONAL CONTROLS

A reinforced concrete cap would be placed over thoseportions of the site that contain buried waste material or haveexhibited soil contamination and are not currently covered with

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concrete or buildings. In addition, the institutional controlsdiscussed in alternative 2 would also be implemented. Thediscussion under section 5.3.2, above, also applies to thisalternative.

This remedial alternative would be easily implemented andmaintained because the necessary materials and technology arereadily available. Long term maintenance would be required toensure the continuing physical integrity of the cap.

The time required to implement the capping alternative isestimated to be approximately 16 months. The present worth costof constructing the concrete cap and lodging the deed restrictionis estimated to be approximately $2,226,000. The present worthcost of maintaining the concrete cap is approximately $442,300over a thirty year period. Therefore the total present worth costof alternative 3 over a 30 year period would be approximately$2,667,900.

5.3.4 ALTERNATIVE 4: IN-SITU STABILIZATION/SOLIDIFICATIONWITH CONCRETE CAP AND INSTITUTIONALCONTROLS

This alternative involves the in-situ (in place)stabilization/solidification of contaminated soil and wastematerial. Solidifying agents and chemical reagents would beinjected into the contaminated soil/waste and mixed with largeaugers to obtain a uniform mixture. The mixture then sets upinto a cement-type matrix. In addition, a concrete cap would beconstructed and institutional controls implemented. Thediscussion included under alternative 3, above, also applies tothis alternative.

The necessary solidifying agents, chemical reagents, andmixing equipment are available from a number of commercialvendors who specialize in this technology. A treatability studywould be required prior to implementation in order to determinethe most effective reagent or combination of reagents forstabilizing the soil/waste. Uniform treatment of theheterogeneous waste material would be difficult to ensure. Longterm maintenance would be required to ensure the continuingphysical integrity of the concrete cap.

The time required to implement the in-situ stabilization/solidification alternative, including performance of atreatability study, is estimated to be approximately 1 to 2years, after which the concrete cap would require approximately16 months to complete. The present worth cost of implementingthe stabilization/solidification technology and constructing theconcrete cap is estimated at approximately $25,665,000. Thepresent worth cost of performance monitoring of the solidifiedmatrix and maintaining the concrete cap is approximately $805,100over a thirty year period. Therefore, the total present worthcost of implementing alternative 4 is approximately $26,470,100.

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6.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES

The NCP has established nine criteria that are used toevaluate remedial alternatives. These criteria serve as thebasis for conducting detailed analyses during the FeasibilityStudy and are subsequently used to determine the appropriatealternative for the site. Attachment D provides a glossary of thenine criteria.

Based on the Baseline Risk Assessment, EPA has determinedthat ground water, surface water, and sediment contamination donot pose a significant threat to human health. Therefore, noremedial action with respect to these media is necessary to ensureprotection of human health and the environment. However, groundwater and surface water monitoring would be conducted to verifythat no unacceptable exposure to risks posed by ground water orsurface water affected by the site occur in the future.

EPA's selected remedy for soil/waste material at the JohnDeere-Ottumwa site is Alternative 2, institutional controls. EPAused the nine criteria to evaluate all of the alternatives. Theselected remedy was determined to provide the best balance oftrade-offs with respect to the criteria. The selected remedy isdescribed in Section 7.0 and discussed below in relation to thecriteria and is compared to the other alternatives under eachcriterion. The criteria are organized into three categories toprioritize the criteria used in making the final selection.

THRESHOLD CRITERIA

The first such category is threshold criteria. Analternative must meet the following two requirements to beconsidered as a final remedy for the site:

6.1 OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

The selected remedy would require continuing maintenance ofthe existing site perimeter fence in order to restrictunauthorized public access. In addition, deed restrictions wouldbe placed on the properties to prevent residential development orother similar exposure situations from occurring on-site in thefuture. These actions will ensure that the sensitive population,children, would not be exposed to site related contaminants abovehealth based levels.

Both Alternatives 3 and 4 would provide protection of humanhealth and the environment by reducing or controlling riskthrough treatment, engineering controls, or institutionalcontrols. The no-action alternative does not provide overall

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protection of human health and the environment and therefore willnot be evaluated further.

6.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATEREQUIREMENTS (ARARS)

Applicable requirements are those state or federalrequirements legally applicable to the release or remedial actioncontemplated that specifically address a hazardous substance,pollutant, contaminant, remedial action, location, or othercircumstance found at the site. If it is determined that arequirement is not applicable, it may still be relevant andappropriate to the circumstances of the release. Requirements arerelevant and appropriate if they address problems or situationssufficiently similar to the circumstances of the release orremedial action contemplated, and are well suited to the site.

There are no federal or state ARARs for the selected remedy,institutional controls.

The remaining alternatives, 3 and 4, would comply with theirrespective ARARs which include RCRA, the Clean Air Act, the CleanWater Act, and state laws.

PRIMARY BALANCING CRITERIA

The second category of criteria is primary balancingcriteria. The following five criteria are used to evaluate thealternatives to determine the option that provides the bestbalance for the final alternative for the site:

6.3 LONG-TERM EFFECTIVENESS AND PERMANENCE

Institutional controls in the form of continued maintenanceof the existing perimeter fence and placement of deed restrictionson future use of the site properties would eliminate the long-termrisks associated with direct contact of site soil and wastematerial to the sensitive population, children. Theserequirements would run with ownership of the land, offeringpermanence of the selected alternative.

Alternatives 3 and 4 would both offer the effectiveness andpermanence associated with institutional controls in addition toconstruction of physical barriers which further inhibit directcontact exposures to all populations, not just the singlesensitive population identified in the Baseline Risk Assessment.The concrete cap would be susceptible to weathering, requiringlong-term maintenance and the solidified matrix would requireregular sample collection to ensure that the additional degree ofprotectiveness provided by these alternatives continuespermanently. Continued ground water monitoring would be requiredfor all alternatives discussed.

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6.4 REDUCTION OF TOXICITY. MOBILITY. OR VOLUME

The selected remedy, institutional controls, would notrequire treatment and so does not offer reduction of toxicity,mobility, or volume of contaminated material. Data provided bythe RI indicates that contaminated material at the John Deere-Ottumwa Works site does not pose an unacceptable health risk tosite workers, the most probable current and future exposurescenario.

Alternative 3, construction of a concrete cap withinstitutional controls, would cover contaminated soils therebyreducing mobility by preventing direct contact with contaminatedsoil and preventing contaminated soil from becoming air-entrainedand so, inhaled.

Alternative 4, stabilization/solidification with a concretecap and institutional controls, would offer the reduction ofmobility provided by alternative 3 as well as a reduction inmobility of contaminants to the ground water, although impact onground water has been shown to be minimal. Additionally, areduction of toxicity would be achieved by the use of reagents tochemically bind the contaminants. The stabilization/solidification technology generally involves some increase involume of treated material due to the addition of reagents andsolidifying agents.

6.5 SHORT-TERM EFFECTIVENESS

The selected remedy would provide a high degree of short-termeffectiveness because no construction activities are required.Risks associated with the present use of the site are consideredacceptable and would not be increased by implementation of thisalternative.

Alternative 3 would involve a temporary increase in thepotential for plant and remedial action workers to be exposed towaste material due to grading of the site required prior toconstruction of the concrete cap.

Implementation of Alternative 4 would involve an increase inpotential exposure of plant and remedial action workers tocontaminated soil/waste during grading of the site and augeringof contaminated soil/waste.

6.6 IMPLEMENTABILITY

Potential problems associated with implementing the selectedremedy are expected to be minimal because a maintenance programfor the existing peripheral fence is currently being carried outby Deere & Company and deed restrictions are easily implemented byfiling with local government officials.

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Alternative 3 would be easily implemented and maintainedbecause the necessary materials and technology are readilyavailable. Long term maintenance would be required to ensure thecontinuing physical integrity of the cap.

A treatability study would be required prior toimplementation of alternative 4, stabilization/solidification.Uniform treatment of the heterogeneous waste material would bedifficult to ensure. Long term maintenance would be required toensure the continuing physical integrity of the concrete cap.

6.7 COST

The cost of implementing the selected remedy is associatedwith lodging the deed restrictions and is estimated to beapproximately $4,000. The cost of maintaining the perimeter fenceis currently covered by the facility's operating budget and sowould require no additional funds.

The total present worth cost of alternative 3 over a 30 yearperiod would be approximately $2,667,900. The total present worthcost of implementing alternative 4 over a 30 year period would beapproximately $26,470,100. The costs associated with alternatives3 and 4 are considered by EPA to be excessive when compared withthe marginal increase in protectiveness offered by thesealternatives over alternative 2.

Although not considered a remedial action activity, theground water monitoring that will be required by EPA is estimatedto be $99,600 over a five year period.

MODIFYING CRITERIA

The third category of criteria is modifying criteria. Thefollowing two criteria are considered when evaluating thealternatives and are used to help determine the final remedy forthe site:

6.8 STATE ACCEPTANCE

The State of Iowa concurs with and supports the selectedremedy at the John Deere-Ottumwa Works site, see Appendix E.

6.9 COMMUNITY ACCEPTANCE

Community acceptance of the institutional controlsalternative, along with ground water and surface water monitoring,has been evaluated following the public meeting held on August 8,1991, and conclusion of the public comment period on August 19,1991. The results of this evaluation are presented in theResponsiveness Summary, Appendix A.

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7.0 SELECTED REMEDY

7.1 GROUND WATER. SURFACE WATER. AND SEDIMENTS

Based on the Baseline Risk Assessment, EPA has determinedthat ground water, surface water, and sediment contamination donot pose a significant threat to human health and, therefore, noremedial action is necessary. However, ground water and surfacewater monitoring would be conducted to verify that no unacceptableexposure to risks posed by ground water and surface water affectedby the site occur in the future.

Pursuant to CERCLA Section 121(c), ground water and surfacewater monitoring data and other information, including siteconditions shall be evaluated no less often than each five years.If results of the five-year review support EPA's currentdetermination that the site does not present a significantpotential threat to human health or the environment via groundwater or surface water, monitoring could be modified orterminated.

If the periodic review indicates that continued monitoring isnecessary to ensure that no potential unacceptable exposures occurin the future, monitoring will be continued for an additionalperiod of time and a second review will be performed. Groundwater and surface water monitoring and periodic reviews willcontinue to ensure that the site does not present a significantpotential threat to human health or the environment.

If, however, an endangerment exists or a periodic reviewindicates that unacceptable migration of site related contaminantsor exposures may occur, EPA has the option to amend the ROD, re-evaluating remedial options.

7.2 SOIL/WASTE MATERIAL

Based on the relative performance of each alternative withrespect to the evaluation criteria, EPA has made the determinationthat the appropriate approach for the John Deere-Ottumwa Workssite is alternative 2, institutional controls, which representsthe best balance of trade-offs among the alternatives.

Alternative 2 satisfies the statutory requirements in Section121 of CERCLA, 42 U.S.C. 9721: it is protective of human healthand the environment; it complies with all federal and staterequirements that are legally applicable or relevant andappropriate for the alternative; and it is cost-effective.

Of the alternatives 2, 3, and 4, all of which meet thethreshold criteria, alternative 2 is by far the least costly.Alternatives 3 and 4 would slightly increase short term risk dueto construction activities. There would be no increase in theshort-term risk during implementation of the selected remedy,

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alternative 2, because no construction activities are required andan effective perimeter fence is already in place.

The selected remedy does not reduce toxicity, mobility, orvolume through treatment. Data provided by the RI shows thatcontaminant levels in all media are low enough as to allowunlimited use of the site and affected media with the exception ofchildren exposed to the waste material itself throughout theirchildhood years. Baseline Risk Assessment results indicate thatsite conditions do not require treatment of contaminatedsoil/waste if children do not live on-site or are not allowed asimilar exposure to the soil/waste material (e.g., schoolbuilding, preschool). Alternatives 3 and 4 would decreasemobility, and alternative 4 would reduce toxicity with someincrease in volume.

The selected remedy would be protective of human health byproviding for institutional controls that require the existingeight foot high chain link fence topped with barbed wire bemaintained indefinitely. Alternative 2, the selected alternative,also requires the lodging of deed restrictions which prevents thedevelopment of residences or other similar exposure situations on-site in the future. These measures would ensure, on a long-termbasis, that the sensitive population, children, are not exposed tosite waste.

There are no federal or state ARARs to be considered for theselected remedy. ARARs for alternatives 3 and 4 would not likelypose any problem for those alternatives.

The selected remedy for the John Deere-Ottumwa site willprovide long-term protection of human health and the environmentand provides the best balance of all factors considered whenevaluating possible options at this site.

During the statutory periodic reviews, EPA will ensure thatdeed restrictions remain in place and are complied with.

8.0 STATUTORY DETERMINATIONS

The selected remedy satisfies the statutory requirements ofSection 121 of CERCLA, 42 U.S.C. § 9721, as follows:

8.1 PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

The selected remedy would be protective of human health byproviding for institutional controls that require the existingeight foot high chain link fence topped with barbed wire bemaintained indefinitely. Alternative 2, the selected remedy, alsorequires the lodging of deed restrictions which prevents thedevelopment of residences or other similar exposure situations on-site in the future. These measures would ensure, on a long-termbasis, that the sensitive population, children, are not exposed to

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site waste, thereby preventing the only potentially unacceptableexposure scenario from occurring. The Hazard Index (HI)associated with children directly contacting waste material isslightly above 1. Restricting access and preventing residentialtype development will preclude children from contacting wastematerial, thereby breaking the exposure pathway. No unacceptablesite related cancer risks were identified.

Implementation of institutional controls will eliminate thelong-term risks associated with direct contact of site soil andwaste material to the sensitive population, children. There wouldbe no increase in the short-term risk during implementation of theselected remedy because no construction activities are requiredand an effective perimeter fence is already in place.

Continued ground water and surface water monitoring willensure that these media are not significantly impacted by the sitein the future and will ensure that cross media contamination doesnot occur from waste material to ground water and surface water.

8.2 COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATEREQUIREMENTS

The selected remedy would comply with all federal and stateARARs. No chemical-specific or location-specific or action-specific ARARs were identified for the site in implementing theselected alternative.

8.3 COST-EFFECTIVENESS

The selected remedy is cost effective because it has beendetermined to provide overall effectiveness proportional to itscost, with the net present value being approximately $4,000 forplacement of deed restrictions. The selected remedy is the leastcostly of remedies that were judged to provide egual protection ofhuman health.

8.4 UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVETREATMENT TECHNOLOGIES TO THE MAXIMUM EXTENT PRACTICABLE

The EPA has determined that the selected remedy representsthe maximum extent to which permanent solutions and treatmenttechnologies can be utilized in a cost-effective manner for theJohn Deere-Ottumwa Works Site. Of those alternatives that areprotective of human health and the environment and comply withARARs, EPA has determined that this selected remedy provides thebest balance in terms of long-term effectiveness and permanence,reduction in toxicity, mobility or volume achieved throughtreatment, short-term effectiveness, implementability, and cost.

All the alternatives evaluated would be protective of humanhealth and the environment on a long-term basis, with theexception of Alternative 1, the no-action alternative. Because noliquid, highly toxic or highly mobile wastes have been identified

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at the site, the additional benefit to be gained from Alternatives3 and 4 over Alternative 2 in ensuring the protection of humanhealth and the environment are marginal.

The selected remedy does not reduce toxicity, mobility, orvolume through treatment. The site waste will not be treatedbecause it is not liquid, highly toxic or highly mobile, andtreatment is not practicable because the benefit from treatment ofthe large volume of waste is marginal compared to the cost of suchtreatment. Alternatives 3 and 4 would decrease mobility, andalternative 4 would reduce toxicity with some increase in volume.

Alternatives 3 and 4 would slightly increase short term riskdue to exposure of waste material during construction activities.There would be no increase in the short-term risk duringimplementation of the selected remedy because no constructionactivities are required and an effective perimeter fence isalready in place.

Implementing institutional controls is readily accomplishedby filing with the proper local officials and a maintenanceprogram for the existing perimeter fence is currently in effect.Ground water monitoring wells are already in place for groundwater sampling. Alternative 3 could be implemented withoutdifficulty but alternative 4 would require a highly complex effortin order to handle the heterogeneous waste material in-situ.

Of the alternatives 2, 3, and 4, which meet the thresholdcriteria, the preferred remedy, alternative 2, is by far the leastcostly. Of all the balancing criteria, above, cost was the mostdecisive factor in the selection decision given the low level ofrisk at the site, followed by the short-term risk andimplementability criteria.

The State of Iowa concurs with and supports the selectedremedy for the John Deere-Ottumwa Works site.

As reflected in the Responsiveness Summary, attached, thecommunity accepts the selected remedy.

8.5 PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT

The selected remedy does not reduce toxicity, mobility, orvolume through treatment. Data provided by the RI shows thatcontaminant levels in all media are low, which allows all butchildren the unlimited use of the site and affected media.Baseline Risk Assessment results indicate that site conditions donot require treatment of contaminated soil/waste if children donot live on-site or are not allowed a similar exposure to thesoil/waste material (e.g., school building, preschool).

Alternatives 3 and 4 would decrease mobility, and alternative4 would reduce toxicity with some increase in volume although bothalternatives would be implemented at substantially greater cost

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than the selected remedy. The site waste will not be treated inimplementing the selected remedy because it is not liquid, highlytoxic or highly mobile, and treatment is not practicable becausethe benefit from treatment of the large volume of waste ismarginal compared to the cost of such treatment.

9.0 DOCUMENTATION OF SIGNIFICANT CHANGES

No significant changes were made in selecting the preferredalternative as described in the Proposed Plan.

ATTACHMENT A

RESPONSE TO PUBLIC COMMENTSON THE

PROPOSED PLANFOR THE

JOHN DEERE-OTTUMWA WORKS SITEOTTUMWA, IOWA

1.0 INTRODUCTION

The United States Environmental Protection Agency (EPA) helda public comment period from July 20 through August 19, 1991 onthe EPA Proposed Plan for the John Deere-ottumwa Works Site inOttumwa, Iowa. The purpose of the public comment period was toprovide interested parties with an opportunity to comment on theProposed Plan. The Proposed Plan was made available on July 16,1991 at the Ottumwa Public Library in Ottumwa, Iowa. Notificationof the public comment period was published in the Ottumwa Courier.

A public meeting was held on August 8, 1991 at the OttumwaPublic Library in Ottumwa, Iowa. At this meeting EPArepresentatives described the alternatives evaluated, presentedthe EPA preferred alternative, and answered questions about theJohn Deere-ottumwa Works site and the remedial alternatives underconsideration.

Section 113(k)(2)(B)(iv) of the Comprehensive EnvironmentalResponse, Compensation, and Liability Act (CERCLA) requires thatEPA respond to significant comments on the EPA Proposed Plan.This Response Summary provides a review and summary of comments onthe Proposed Plan. In addition to summarizing significant concernsand questions, the Response Summary presents EPA's responses tothose concerns.

2.0 PUBLIC COMMENTS AND EPA RESPONSES

2.1 COMMENTS FROM INTERESTED CITIZENS

2.1.1 One written comment requested that the U.S.Environmental Protection Agency give a clean bill of health to theJohn Deere-Ottumwa Works site and discontinue any further testing.

EPA Response

While the Baseline Risk Assessment indicates that potentialexposures to site contaminants are within acceptable ranges foradults, waste material containing hazardous constituents willremain on-site and poses a potential future exposure risk tochildren (children currently are not exposed to site waste

material). Therefore, the limited remedial action ofinstitutional controls must be implemented.

Also, to ensure that unacceptable exposures to sitecontaminants do not occur in the future via ground water orsurface water, monitoring of ground water and surface water willbe conducted for a minimum of five years in order to verify groundwater data collected during the Remedial Investigation.

2.1.2 One commenter at the public meeting expressedappreciation for what Deere & Company, EPA, and IDNR have done andare going to do at the site, but remarked that EPA had surveyedcommunity reaction. The commenter had not heard a report back.

EPA Response

EPA did interview several members of the public regarding thesite and site activities. The information received was compiledin a Community Relations Plan for the site. The CommunityRelations Plan is available in the Administrative Record in theOttumwa Public Library.

2.1.3 One commenter at the public meeting on behalf of Deere &Company expressed agreement with the conclusion and recommendationof the proposed plan and expressed Deere & Company's commitment tocarrying out the proposed plan.

EPA Response

The willingness of Deere & Company to carry out the proposedplan enhances the implementability of the selected remedy.

2.1.4 One commenter at the public meeting stated concerns overwhether the government or Deere & Company would bear costs for thework. The commenter was particularly concerned about how costsimposed on Deere & Company would affect jobs in the community.The commenter asked "if it's no danger to the public, why thecontinued monitoring?" The commenter also suggested that if thereis no risk associated with the site, EPA should remove it from theSuperfund list.

EPA Response

Deere & Company has paid all costs to date and is obligatedto pay all EPA costs to date under the existing Consent Order.EPA does not have knowledge how costs affect Deere & Company'soperations or how it might affect jobs in the area. Future costs,including ground water and surface water monitoring, arerelatively minimal compared to other Superfund sites.

Waste material remains on-site and EPA is therefore requiredby statute, CERCLA Section 121(c), to conduct a periodic reviewnot less than every five years to ensure the remedy is protectiveof human health and the environment. Continued ground water andsurface water monitoring will be conducted for a minimum of fiveyears to provide data to base the five-year review on. The sitemay be considered for deletion from the National Priority List("Superfund" list) after a minimum of one five-year review.

ATTACHMENT B

FIGURES

SOURCE: USGS 7.5 Minute Topographic Maps, OTTUMWA NORTH & SOUTH. IOWA Quadrangles, 1976

N1000 2000

~ mmSCALE IN FEET

4000IOWA

^•fGERAGHTY& MILLER, INC.

Environmental Service!

FIGURE 1SITE LOCATION

REMEDIAL INVESTIGATIONJOHN DEERE OTTUMWA WORKS

OTTUMWA, IOWA0101301 -0084.01

JOHN DEEREOTTUMWA

WORKS

NOTE: THE SITE FEATURES ARE BASED UPON ANAREAL PHOTOGRAPH OF THE FACILITYWHICH WAS TAKEN ON APRIL 21, 1989.

250 500

APPROXIMATE SCALE IN FEET

•'GERAGHTYMILLER, INC.

FIGURE 2SITE FEATURES

REMEDIAL INVESTIGATIONJOHN DEERE OTTUMWA WORKS

OTTUMWA, IOWACC1301-DOUCE

HAZARDOUSWASTE STORAGE

Lake \ \

FORMERLANDFILLAREAS

JOHN DEEREOTTUMWA

WORKS

M-2/A SOUTHCAR AREA

»\250 500 1000

APPROXIMATE SCALE IN FEET

GERAGHTYr<5? MILLER, INC.t*'lr,,m,,,,l

LEGEND

«0-1 + SEDIMENT SAMPLING LOCATION

M-1 • SOIL BORING LOCATION

FIGURE 3SOIL BORING AND

SEDIMENT SAMPLING LOCATIONSREMEDIAL INVESTIGATION

JOHN DEERE OTTUMWA WORKSOTTUMWA, IOWA

HAZARDOUSWASTE STORAGE

'\A«T*fF1Y^A.tW-1

. ./ -i-^-*^ ̂X *>-.--K;.^*&:-:<*'-.*_-_^^'

N\250 500 1000

APPflOXIMATt SCALE IN FEET

•fGERAGHTY'g MILLER. INC.

Emriremmfmltl Strrieti

LEGEND

*W-1 O MONITORING WELL LOCATION

n-1* PIEZOMETER LOCATION

•TAfF 1A SURFACE WATER LEVEL GAGING STATION

**-l A SURFACE WATER SAMPLING LOCATION

FIGURE HMONITORING WELL,

PIEZOMETER ANDSURFACE WATER

GAGING LOCATIONSREMEDIAL INVESTIGATION

JOHN DEERE OTTUMWA WORKSOTTUMWA, IOWA

ceuoi -OOMJX

HAZARDOUSWASTE STORAGE

250 500________1000

APPROXIMATE SCALE IN FEET

-^GERAGHTYMILLER, INC.

LEGEND

«0-1 + SEDIMENT SAMPLING LOCATION

M-1 • SOIL BORING LOCATION

•WM O MONITORING WELL LOCATION

K-1 • PIEZOMETER LOCATION

*TAFF 1A SURFACE WATER LEVEL GAGING STATION

«W-1 A SURFACE WATER SAMPLING LOCATION

JM-1 9 JAMES MONTGOMERY SOIL BORING LOCATION

ESTIMATED LATERAL EXTENT OF FILL FIGURE S5ESTIMATED LATERAL

EXTENT OF FILLREMEDIAL INVESTIGATION

JOHN DEERE OTTUMWA WORKSOTTUMWA, IOWA

ATTACHMENT C

TABLES

Page 1 of 2

Table 1 Occurrence of Constituents in Phase II Unfiltcred Ground-Water Samples', John DeereOttumwa Works, Ottumwa, Iowa.

Constituents Range* Mean" UCL Background4

VOCs

AcetoneBenzene1,2-DichloroethaneEthylbcnzeneTolueneXylene (total)

0.002 - 0.0050.002 - 0.00250.0025 - 0.0030.0025 - 0.0080.0025-0.0150.0025-0.041

0.0048 (NA)0.0025 (NA)0.0025 (NA)0.0033 (NA)0.0035 (NA)0.0074 (NA)

0.00520.00250.00260.00430.00530.013

<0.010<0.005<0.005<0.005<0.005<0.005

Semi-VOCs

Bis(2-ethylhexyl)phthalateDi-n-butylphthalateJ,2,4-Trichlorobcnzene

Inorganics

0.001 - 0.0050.001 -0.0050.004 - 0.005

0.0046 (NA)0.0045 (NA)0.0049 (NA)

0.00520.00510.0050

<0.010<0.010<O.OJO

AluminumArsenicBariumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseNickelPotassiumSilverSodiumVanadium

0.160.001 •

0.130.0025

97-0.003 •0.005 •

0.00250.32

0.000515-1.1 •

0.00451.7-

0.002 -15-

0.002 -

-7.5- 0.027- 1.1- 0.005240

-0.018- 0.028- 0.032-32- 0.093-50-7.6- 0.0588.20.0051470.031

2.6 (<0.027) 3.80.0084 (<0.002) 0.013

0.38 (0.29) 0.510.0027 (<0.005) 0.0031

150(158) 1700.0060 (<0.006) 0.00850.0093 (<0.01) 0.0130.011 (<0.005) 0.016

14 (6.8) 200.0099 (<0.001) 0.023

33 (36) 373.3 (3.5) 4.4

0.016 (0.0075) 0.0244.9 (6.2) 5.9

0.0025 (<0.004) 0.003155 (64) 77

0.011 (<0.004) 0.015

5.30.0230.63

0.006166

0.0140.0790.033

410.019

434.3

0.116.6

<0.00429

0.074

Page 2 of 2

Table 1 Occurrence of Constituents in Phase II Unfiltered Ground-Water Samples', John DeereOttumwa Works, Ottumwa, Iowa.

Constituents Range* Mean* UCL Background"

Inorganic (cont1)

Zinc 0.007-0.17 0.050(0.020) 0.077 0.11

Concentrations reported in milligrams per liter (mg/L).

NA Not analyzed.

UCL Upper 95 percent confidence limit.

a Unfil tered Phase II sample data from J2 samples (GMMW01 through GMMW11 and GMPZ02).

b Minimum concentration in range represents either the lowest detected concentration or one-half thedetection l imi t for non-detects.

c Ar i thmet ic mean of unf i l te red sample data using one-half the detection limit for non-detects.Values in parenthesis ( ) arc the ar i thmet ic mean of Phase II fi l tered sample data.

d Background sample is GMMW12-02 from the Phase II unf i l tered sample.

728johnd«iT/occeoo. *l

Table 2 Occurrence of Constituents in Surface-Water and Sediment From Black Lake,John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent Detected Water*Concentration

(mg/L)

Detected Sediment*Concentration

(mg/kg)

Inorganics

AluminumArsenicBariumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseNickelPotassiumSodiumVanadiumZinc

0.40<0.005

0.43<0.00129<0.01<0.01<0.02

0.75<0.005110.15

<0.014.6

31<0.01

0.038

6500.648.71.2

1,2003.54.66.5

3,600<0.61

720150

8.58239

4.819

a Data from GMSW-01.b Data from GMSD-01.

707John<Jeere/12.tt>l

Table 3 Occurrence of Constituents in Drainage Ditch Sediment Samples, John DeereOttumwa Works, Ottumwa, Iowa.

Constituent Range* Mean" UCLSiteBackground*

Inorganics

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseNickelPotassiumSodiumVanadiumZinc

2,700 - 3,4002.9 - 3.870-85

0.28-0.312.8 - 3.3

4,300 - 6,3007.1 - 7.55.9 - 8.16.1 - 6.6

8,700 - 10,0009.0 - 37

1,700- 1,900300 - 400

12- 14350 - 42035-4610- 1237-53

3,0003.4770.293.05,0007.37.26.39,400211,80036013400401147

3,4003.8850.313.36,3007.58.16.610,000371,90040014420461253

8.7007.61701.16.47,90015122019,000392,800640251,2008925110

Concentrations reported in milligrams per kilogram (mg/kg).

UCL Upper 95 percent confidence level.

a Minimum concentration in range represents either the lowest detected concentrationor one-half the detection limit for non-detects.

b Arithmetic mean of three samples (GMSD-03, GMSD-04, and GMSD-05) using one-halfthe detection limit for non-detects.

c Background sample is GMSD-02.

707johndeere/11.ttil

Table A Occurrence of Constituents in Landfill 1, Subsurface Material Samples, JohnDeere Ottumwa Works, Ottumwa, Iowa.

Constituent

OreanicsAcetoneBis(2-ethylhexyl)

phthalateTetrachlorocthenecPAHstPAHs

InorganicsAluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSeleniumSodiumVanadiumZincCyanide

Range*

0.005 - 0.0510.18-0.9

0.003 - 0.0391.1 -231.6-27

1,500- 11,0000.27 - 2615-240

0.14 - 3.01.0 - 32

2,000 - 270,0002.5- 1401.5- 151.6-70

4,500- 59,0003.2-810

50 - 3,800160-640

0.027 - 0.495.2 - 28

150- 1,3000.027 - 3.126- 1,800

3.2 - 2710-2,8000.16-53

Mean*

0.0220.29

0.0073.74.8

4,9005.61000.787.3

38,000257.619

25,000120

2,2003800.116

6600.5036014

4206.1

UCL

0.0340.44

0.0158.19.8

7,40011

1401.413

92,000521033

37,000280

2,9004700.20209201.171020

98017

MeanBackground0

<0.01<0.35

<0.005<0.39<0.39

1,7004.285

0.653.7

1,800107.74 8

14,0009.9

1,400400

<0.05913

370<0.59

811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of nine samples using one-half the detection limit for non-detects.c Arithmetic mean background using two samples: GMSB13-03 (4-6 ft. bis) and GMSB13-05

(8-10 ft. bis).cPAHs Carcinogenic PAHs.tPAHs Total PAHs; includes carcinogenic and noncarcinogenic PAHs.

716Johnd«ere*3/3.tt>l

Table 5 Occurrence of Constituents in Landfills 2 and 3, Subsurface and CompositeMaterial Samples, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Oreanics

AcetoneDibenzofuranMethylene ChlorideToluenecPAHstPAHsXylene

Inorganics

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSeleniumSodiumVanadiumZincCyanide

Range*

0.005-0.180.19 - 5.6

0.003 - 0.0380.003 - 0.009

1.3-142.8 - 94

0.003 - 0.007

2,300 - 9,6001.9 - 3651 - 5700.14-2.02.2 - 41

2,200 - 16,0005.9 - 365.0- 125.9 - 48

7,700 - 49,0005.6 - 150

790 - 2,900280 - 690

0.029 - 0.169.5 - 36

430 - 1,3000.28 - 3.397 - 4608.9 - 22

29 - 25,0000.14-20

Mean"

0.081.0

0.0080.0044.4

170.003

5,7009.01801.09.5

8,100138.219

22,00062

1,900400

0.055208300.8320017

2,3002.9

UCL

0.111.8

0.0140.0046.2

300.004

6,70015

2601.315

11,000179.526

29,00088

2,200470

0.07725

9601.426019

6,0006.0

MeanBackground'

<0.01<0.39

<0.005<0.005<0.39<0.39<0.005

1,7004.285

0.653.7

1,800107.74 8

14,0009.9

1,400400

<0.05913

370<0.59

811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of 12 samples using one-half the detection limit for non-detects.c Arithmetic mean background using two samples: GMSB13-03 (4-6 ft. bis) and GMSB13-05

(8-10 ft. bis).cPAHs Carcinogenic PAHs.tPAHs Total PAHs; includes carcinogenic and noncarcinogenic PAHs.716Johndeere*3/4.tbl

Table 6 Occurrence of Constituents in Drum Storage/Hazardous Waste Storage Area,Surficial Material Samples, John Deere Ottumwa Works, Ottumwa, Iowa.

MeanConstituent Range1 Mean* UCL Background1

OreanicsAcetone 0.005 - 0.078 0.03 0.078 <0.01Methylene Chloride 0.003d 0.003 0.003 <0.005cPAHs 0.38 - 0.47 0.42 0.47 <0.39tPAHs 1.2 - 1.7 1.4 1.7 <0.393,3-Dichloroben- 0.37* - 0.394 0.38 0.39 <0.78zidine

InorganicsAluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSeleniumSodiumVanadiumZincCyanide

6,000 - 6,4003- 16

75 - 4000.84 - 1.18 8 - 1 4

16,000-42,00014- 70

6.7 - 8.72 2 - 4 3

19,000-48,00052 - 350

460 - 1,60069 - 870

0.028 - 0.08218-23

750-8200.28 - 1.2160-480

13-20340 - 6400.14 - 1.0

6,1008.31900.9511

26,000358.029

36,000170

1,000520

0.047217800.8628017

4900.43

6,40016

4001.114

42,000708.743

48,000350

1,600870

0.08223

8201.2

480206401.0

1,7004.285

0.653.7

1,800107.74 8

14,0009.9

1,400400

<0.05913

370<0.59

811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of three samples using one-half the detection limit for non- detects,c Arithmetic mean background using two samples: GMSB13-03 (4-6 ft. bis) and GMSB13-

05 (8-10 ft. bis).d Not detected in surficial soil, but because it was detected in subsurface soil, the value

shown represents one-half the detection limit.cPAHs Carcinogenic PAHs.tPAHs Total PAHs; includes carcinogenic and noncarcinogenic PAHs.716johndeere«3/5.tbl

Table 7 Occurrence of Constituents in Drum Storage/Hazardous Waste Storage Area,Subsurface Samples, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Oreanics

AcetoneMethylene ChloridecPAHstPAHs3,3-Dichloroben-

zidine

Inorganics

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSeleniumVanadiumZincCyanide

Concentrations reportedUCL Upper 95 percent

Range' Mean* UCL

0.005 - 0.095 0.036 0.0950.003 - 0.01 0.005 0.010.37 - 0.56 0.44 0.56

1.1 - 1.7 1.3 1.70.21 - 0.40 0.33 0.40

2,800-10,000 6,000 10,0003.0-10 5.4 1047-200 120 200

0.14 - 1.0 0.54 1.02.6-10 5.2 10

4,700-21,000 15,000 21,0006.4 - 22 12 223.2-10 6.8 109.7-32 18 32

8,600 - 32,000 17,000 32,0001 0 - 7 7 34 77

2,100-2,800 2,400 2,800190-830 450 830

0.028 - 0.061 0.04 0.0616.9 - 45 22 45

360-1,100 670 1,1000.28 - 0.31 0.30 0.31

7.5-26 15 2648 - 1,300 470 1,3000.14-0.30 0.24 0.30

in milligrams per kilogram (mg/kg).confidence limit.

MeanBackground*

<0.01<0.005<0.39<0.39<0.78

1,7004.285

0.653.7

1,800107.74.8

14,0009.9

1,400400

<0.05913

370<0.59

1826

<0.01

a Minimum concentration in range represents either the lowest detected concentration orone-half the detection limit for non-detects.

b Arithmetic meanc Arithmetic mean

05 (8-10 ft. bis).

of three samples using one-half the detection limit forbackground using two samples: GMSB 13-03 (4-6 ft. bis)

non-detects.andGMSB13-

cPAHs Carcinogenic PAHs.tPAHs Total PAHs; includes carcinogenic and noncarcinogenic PAHs.

Table 8 Occurrence of Constituents in Oil Spill Area, Surficial Soil Samples, John DeereOttumwa Works, Ottumwa, Iowa.

Constituent

Orcanics

AcetoneToluene

Inorganics

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseNickelPotassiumSodiumVanadiumZincCyanide

Range*

0.006*0.003*

10,000-3.3-160-0.9-5.0-

2,800 -12-

6.2-93-

15,000-12-

2,100-390-

17-620-

68-22-

45-0.15-

14,0004.81901.96.73,900189.01719,000272,50079022

1,30086288600.45

Mean"

0.0060.003

11,0004.11701.45.6

3,400157.912

17,00018

2,30060019

94075253200.25

UCL

0.0060.003

14,0004.81901.96.7

3,900189.017

19,00027

2,50079022

1,30086288600.45

MeanBackground0

<0.01<0.005

1,7004.285

0.653.7

1,800107.74.8

14,0009.9

1,40040013

370811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of three samples using one-half the detection limit for non- detects,c Arithmetic mean background using two samples: GMSB13-03 (4-6 ft. bis) and GMSB13-05

(8-10 ft. bis),d Not detected in surficial soil, but because it was detected in the subsurface soil, the value

represents one-half the detection limit.

Table 9 Occurrence of Constituents in Oil Spill Area, Subsurface Soil Samples, JohnDeere Ottumwa Works, Ottumwa, Iowa.

Constituent Range* Mean* UCLMean

Background1

Organics

AcetoneToluene

Inorganics

0.005 - 0.370.003 - 0.095

0.0160.033

0.0370.95

<O.OI<0.005

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseNickelPotassiumSodiumVanadiumZincCyanide

1,500 - 7,5000.91 - 2.914- 160

0.13- 1.41.1 -5.3

610-3,7004.6-114.1-112.0- 10

4,300- 16,0001.3-13

920 - 2,300120 - 7006.7 - 21

120-74030-925.1 - 1813-51

0.13-0.15

4,0002.281

0.722.9

1,7007.36.85.4

8,8006.5

1,40047014

350601130

0.14

7,5002.91601.45.3

3,700111110

16,00013

2,3007002174092

• 1851

0.15

1,7004.285

0.653.7

1,800107.74.8

14,0009.9

1,40040013

370811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of three samples using one-half the detection limit for non- detects,c Arithmetic mean background using two samples: GMSB13-03 (4-6 ft. bis) and GMSB13-05

(8-1 Oft . bis).

716>ohndeere«3/8.1bl

Table 10 Occurrence of Constituents in South Scar Area, Surficial Soil Samples, JohnDeere Ottumwa Works, Ottumwa, Iowa.

Constituent Range' Mean" UCLMean

Background'

Organics

AcetoneNaphthaleneTetrachloroetheneXylene

0.006 - 0.0490.19 - 0.20

0.003 • 0.0480.003*

0.0240.19

0.0180.003

0.0490.200.0480.003

<0.39<0.005<0.005

Inorganics

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSodiumVanadiumZincCyanide

4,400 - 7,9002.8 - 4.287 - 160

0.63 - 0.843.2 - 6.0

4,300 - 9,60013-218.6 - 109.2 - 38

11,000-24,00020-80

2,100-2,800260 - 660

0.028 - 0.0613-21

510-91066 - 14014 -21

54 - 1000.154

5,7003.61100.714.7

6,500189.422

18,00046

2,400480

0.03918

680921778

0.15

7,9004.21600.846.0

9,600211038

24,00080

2,8006600.0621

910140211000.15

1,7004.285

0.653.7

1,800107.74 8

14,0009.9

1,400400

<0.05913

370811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of three samples using one-half the detection limit for non- detects,c Arithmetic mean background using two samples: GMSB13-03 (4-6 ft. bis) and GMSB13-05

(8-10 ft. bis).d Not detected in the surficial soil, but because it was detected in subsurface soil, the value

represents one-half the detection limit.

707johndeere*2y9.tt>l

Table n Occurrence of Constituents in South Scar Area, Subsurface Soil Samples, JohnDeere Ottumwa Works, Ottumwa, Iowa.

Constituent Range" Mean' UCLMean

Background0

Oreanics

AcetoneNaphthaleneTetrachloroetheneXylene

0.005 - 0.0640.18 - 1.2

0.003*0.003 - 0.16

0.0310.37

0.0030.029

0.0490.700.0030.08

<0.01<0.39

<0.005<O.OOS

Inorganics

AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSodiumVanadiumZinc

Cyanide

1,000- 11,0000.3 - 8.932 - 1900.14- 1.3J.I -5.7

2,500 - 6,5004.1 - 183.4 - 1 11.7 - 24

4,800 - 22,0001.5-27

2,100-3,500230 - 580

0.028 - 0.0338.3 - 25

100- 1,20038- 1405.2 - 2711-85

0.14 - 0.36

4,7003.394

0.563.1

5,2009.47.39.8

11,00010

2,800400

0.03114

540771442

0.19

7,9005.91500.964.5

6,500149.618

17,00019

3,200530

0.033209201102169

0.26

1,7004.285

0.653.7

1,800107.74 8

14,0009.9

1,400400

<0.05913

370811826

<0.01

Concentrations reported in milligrams per kilogram (mg/kg).UCL Upper 95 percent confidence limit.a Minimum concentration in range represents either the lowest detected concentration or

one-half the detection limit for non-detects.b Arithmetic mean of six samples using one-half the detection limit for non- detects,c Arithmetic mean background using two samples: GMSB13-03 (46 ft. bis) and GMSB13-05

(8-1 O f t . bis),d Not detected in subsurface soil, but because it was detected >* surficial soil, the value

represents one-half the detection limit.

707Johodeere*3/10.tt)l

TABLE 12

INDICATOR COMPOUNDS USED IN RISK ASSESSMENT CALCULATIONS

Inorganics

ArsenicBarium

BerylliumCadmiumChromiumCopperCyanideLead

MercuryNickelSeleniumZinc

Volatile Organics

AcetoneMethylene ChlorideTetrachloroethene

TolueneXylenes

Semi-Volatile Organics

Dibenzofuran3,3-Dichlorobenzidine

Carcinogenic Polycyclic Aromatic HydrocarbonsNon-Carcinogenic Polycyclic Aromatic Hydrocarbons

Table 13 Reference Doses (RfD), and Cancer SlopeFactors <SF) for Indicator Compounds

RfD fmg/ke-dav)

Polvcvclic Aromatics

Carcinogenic PAHsBenzo(a)pyrenek

Total PAHsNaphthalene'

ND

4.0E-3

ND

(4.0E-3)

SF fmg/kg/davVConstituent

InorganicsArsenicBariumBerylliumCadmium (water)Cadmium (food)Chromium (VI)CopperCyanide (free)LeadMercuryNickelSeleniumZinc

Volatile OrganicsAcetoneMethylene ChlorideTetrachloroetheneTolueneXylenes

Semi-VolatileOrganics

Dibenzofuran3,3-Dichloro-

benzidine

Oral

l.OE-35.0E-25.0E-35.0E-4l.OE-35.0E-33.7E-22.0E-2

ND3.0E-42.0E-23.0E-32.0E-1

J.OE-16.0E-2l.OE-22.0E-12.0E+0

NDND

Inhalation*

(1JE-03)l.OE-4

(5.0E-3)(5.0E-4)(l.OE-3)(5.7E-07)l.OE-02

(2.0E-2)ND

8.6E-05(2.0E-2)(3.0E-3)l.OE-2

l.OE-18.6E-1

(l.OE-2)6.0E-19.0E-2

NDND

Oral

1.75—4.3E+0

*••--ND-•--

.7.5E-35.1E-2--

ND4.5E-1

Inhalation

5.0E+1—8.4E+06.1 E+06.1 Ei-04.1E+1--ND.

8.4E-1--

-1.4E-21.8E-03--

NDND

1.15E+1 6.1 E+0

a If inhalation data were not available, oral data were used (numbers in parentheses).b Data for bcnzo(a)pyrenc were used to represent all carcinogenic PAHs.c Data for naphthalene were used to calculate risk of noncarcinogenic effects for all PAHs.ND No data.* Not a carcinogen via oral exposure.

References: IRIS, 1991; USEPA, 1990a; USEPA, 1986d.nejotindeere/IS.tbl

Table 14 Potable Ground-Water Exposure Doses (GWExDs), Hazard Quotients, andExcess Lifetime Cancer Risks, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Cancer Effects

Arsenic

Non-Cancer Effects

AcetoneTolueneXyleneArsenicBariumCadmiumChromiumCopperLeadNickelZinc

Cgw GroundGWExD Ground

Cgw

0.013

0.00520.00530.0130.0130.51

0.00310.00850.0160.0230.0240.077

water concentration (mg/L).water exposure dose (mg/kg/di

GWExD

1.6E-04

ELCR

1.5E-041.5E-043.7E-043.7E-041.5E-028.9E-052.4E-044.6E-O46.6E-046.9E-042.2E-03

HI

iv) calculated using the

Cancer Risk andHazard Quotient

3E-04

3E-04

IE-038E-042E-044E-013E-012E-015E-02IE-02NQ3E-02IE-02

1E+00

95 percent upper confidence limit concentration (Table 47).HI Hazard index (sum of the hazard quotients[GWExD/reference

doses from Table 64]).ELCR Excess lifetime cancer risk (GWExD x cancer slope factor

from Table 64).NQ Not quantifiable. Hazard quotient could not be calculated

because there is no reference dose for lead. The potentialhealth risk is evaluated using the UBK model.

7I6jd*)/67.wtl

Current Site Worker Soil Exposure Doses, Hazard Quotients, and ExcessTable 15 Lifetime Cancer Risks, Drum Storage Hazardous Waste Storage Area, John

Deere Ottumwa Works, Ottumwa, Iowa.

Constituent Cs SExD (O/D) SExD(Inh)Cancer Risk andHazard Quotients

Cancer Effects___

ArsenicBerylliumCadmiumChromium3,3-DichlorobenzidineMethylcne chlorideNickelcPAHs

161.11470

0.390.003

230.47

2. IE-065.4E-071.1E-056.3E-052.1E-073.3E-092. IE-052.5E-07

2.4E-091.6E-102. IE-09l.OE-08S.8E-114.4E-133.4E-097.0E-11

ELCR

4E-062E-06IE-089E-084E-072E-113H-C93E-06

IE-05

Non-Cancer Effects

AcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanide3 ,3-DichlorobenzidineLeadMethylene chlorideNickeltPAHsSeleniumZinc

0.07816

4001.11470431.0

0.39350

0.003231.71.2640

2.0E-075.0E-068.4E-041.3E-062.5E-05l.SE-041.7E-053.3E-064.9E-07l.OE-047.7E-094.8E-052. IE-063.8E-073.2E-04

2.7E-115.5E-091.4E-073.8E-104.8E-092.4E-081.5E-083.5E-101.3E-101.2E-07l.OE-127.9E-095.9E-104.1E-102.2E-07

HI

2E-065E-032E-023E-043E-027E-025E-042E-04

NQNQ

IE-072E-035E-04IE-042E-03IE-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

13jofaiM)eere/t23.wk1

Current Site Worker Soil Exposure Doses, Hazard Quotients, and ExcessTable 16 Lifetime Cancer Risks, Oil Spill Area, John Deere Ottumwa Works,

Ottumwa, Iowa.

Constituent

Cancer Effects

AnericBerylliumCadmiumChromiumNickel

Non-Cancer Effects

AcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadNickelTolueneZinc

Cs

4.81.96.71822

0.0064.81901.96.71817

0.452722

0.003860

SExD (0/D)

6.4E-079.4E-075.2E-061.6E-062.0E-05

1.5E-081.5E-064.0E-042.2E-061.2E-053.8E-056.9E-061.5E-067.8E-064.6E-057.7E-094.3E-04

SExOOnh)

7.1E-102.8E-109.9E-102.7E-093.3E-09

ELCR

2.1E-121.7E-096.6E-086.6E-102.3E-096.2E-095.9E-091.6E-109.3E-097.6E-09l.OE-123.0E-07

HI

Cancer Riskand HazardQuotients

IE-064E-066E-09IE-073E-09

5E-06

2E-072E-039E-034E-O42E-028E-032E-047E-05NQ2E-034E-082E-03

5E-02

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

13johndeereA24.wkl

Table 17 Current Site Worker Soil Exposure Doses, Hazard Quotients, and ExcessLifetime Cancer Risks, South Scar Area, John Deere Ottumwa Works,Ottumwa, Iowa.

Constituent Cs SExD (O/D) SExD(Inh)

Cancer Risksand HazardQuotients

Cancer Effects

ArsenicBerylliumCadmiumChromiumNickelTetrachloroetbene

Non-Cancer Effects

AcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadMercuryNickeltPAHsTetrachloroetheneZinc

4.2O.S46.02121

0.048

0.0494.2160

0.846.02138

0.1580

0.0721

0.200.048

100

5.6E-074.2E-074.6E-061.9E-051.9E-055.3E-08

1.3E-071.3E-063.3E-049.7E-071. IE-054.4E-051.5E-055.0E-072.3E-056. IE-084.4E-052.5E-071.2E-075.0E-05

6.2E-101.2E-108.9E-103. IE-093. IE-097. IE-12

ELCR

1.7E-111.4E-095.5E-082.9E-102. IE-097.2E-091.3E-085.2E-112.8E-082.4E-117.2E-096.9E-111.7E-113.5E-08

HI

IE-062E-065E-09IE-073E-093E-09

3E-06

IE-06IE-037E-032E-04IE-022E-024E-042E-05NQ4E-042E-036E-05IE-053E-04

4E-02

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (m£/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

13johadeere/t25.wkl

Table is Future Site Worker Soil Exposure Doses, Hazard Quotients and ExcessLifetime Cancer Risks, Landfill 1, John Deere Ottumwa Works,Ottumwa, Iowa.

Constituent

Cancer EffectsArsenicBerylliumCadmiumChromiumNickelcPAHsPCE

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadNickeltPAHsSeleniumZincPCE

Cs

111.41352208.1

0.015

0.03411

1401.4135233

17.028020

9.81.1980

0.015

SExD (0/D)

1.5E-066.9E-07l.OE-054.7E-051.8E-054.3E-061.6E-08

8.7E-083.4E-062.9E-041.6E-062.3E-051. IE-041.3E-055.6E-058. IE-054.2E-051.2E-053.4E-074.9E-043.8E-07

SExD(Inh)

1.6E-092. IE-101.9E-097.7E-093.0E-091.2E-092.2E-12ELCR

1.2E-113.8E-094.8E-084.8E-104.5E-091.8E-081. IE-085.9E-099.7E-086.9E-093.4E-093.8E-103.4E-075.2E-12

HI

Cancer Risk andHazard Quotients

3E-063E-06IE-083E-072E-095E-058E-106E-05

9E-073E-036E-033E-042E-025E-024E-043E-03

NQ2E-033E-03IE-042E-034E-06

IE-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to coil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/AD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

71 tj frl i i«/74.»tl

Table 19 Future Site Worker Soil Exposure Doses, Hazard Quotients and ExcessLifedme Cancer Risks, Landfills 2 and 3, John Deere Ottumwa Works,Ottumwa, Iowa.

Constituent Cs SExD (O/D) SExD(Inh)Cancer Risk andHazard Quotients

Cancer EffectsArsenicBerylliumCadmiumChromiumMethylene chlorideNickelcPAHs

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadMetbylene chlorideNickeltPAHsSeleniumZincXylenesDibenzofuran

151.31517

0.01425

6.2

0.1115

2601.3151726

6.088

0.01425301.4

6,0000.004

1.8

2.0E-066.4E-071.2E-051.5E-051.5E-082.2E-053.3E-O6

2.8E-074.7E-065.4E-041.5E-062.7E-053.5E-051. IE-052.0E-052.5E-053.6E-085.2E-053.7E-054.4E-073.0E-03l.OE-083.9E-07

2.2E-091.9E-102.2E-092.5E-092. IE-123.7E-099.2E-10

ELCR

3.8E-115.2E-099.0E-084.5E-105.2E-095.9E-099.0E-092. IE-093.0E-084.8E-128.6E-09l.OE-084.8E-102. IE-061.4E-126.2E-10

HI

4E-063E-06IE-08IE-07IE-103E-094E-054E-05

3E-065E-03IE-023E-043E-022E-023E-04IE-03NQ

6E-073E-039E-03IE-042E-025E-09

NQ

9E-02

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/AD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

TlfJntailnnrr-T - II

Table 20 Adult Resident Soil Exposure Doses, Hazard Quotients, and Excess LifetimeCancer Risks, Drum Storage/Hazardous Waste Storage Area, John DeereOttumwa Works, Ottumwa, Iowa.

Constituent

Cancer Effects

ArsenicBerylliumCadmiumChromium3 ,3-DicbJorobenzidineMethylene chlorideNickelcPAHs

Cc

161.11470

0.390.003

230.47

SExD (O/D)

7.7E-061.9E-063.9E-052.2E-047.4E-071.2E-087.4E-059.0E-07

SExD(Inh)

5.3E-103.6E-114.6E-102.3E-091.3E-119.9E-147.6E-101.6E-11

Cancer Rickand HazardQuotients

IE-058E-063E-099E-083E-079E-116E-10IE-05

ELCR 3E-05

Non-Cancer Effects

AcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanide3,3-DichlorobenzidineLeadMethylene chlorideNickeltPAHsSeleniumZinc

0.07816

4001.11470431.0

0.39350

0.003231.71.2640

7. IE-071.8E-053.0E-034.5E-069.0E-055.2E-046.2E-051.2E-051.7E-063.6E-042.7E-081.7E-047.6E-061.3E-061. IE-03

6.0E-121.2E-093. IE-088.5E-111. IE-095.4E-093.3E-097.7E-113.0E-112.7E-082.3E-131.8E-091.3E-109.2E-114.9E-08

HI

7E-062E-026E-029E-049E-02IE-012E-036E-04NQNQ5E-079E-032E-034E-046E-03

3E-01

Ct Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

13johndeereA26.wkl

Table 21 Adult Resident Soil Exposure Doses, Hazard Quotients, and Excess LifetimeCancer Risks, Oil Spill Area, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Cancer Effect*ArsenicBerylliumCadmiumChromiumNickel

Cs

4.81.96.71822

SExD (O/D)

2.3E-063.4E-061.9E-055.8E-057.0E-05

SExD(Inh)

1.6E-106.3E-112.2E-105.9E-107.3E-10

Cancer Rick andHazard Quotients

4E-06IE-05IE-092E-086E-10

ELCR 2E-05

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadNickelTolueneZinc

0.0064.81901.96.71817

0.452722

0.003860

5.5E-085.4E-061.4E-037.8E-064.3E-051.3E-042.5E-055.3E-062.8E-051.6E-042.7E-081.5E-03

4.6E-133.7E-101.5E-081.5E-105.2E-101.4E-091.3E-093.5E-112. IE-091.7E-092.3E-136.6E-08

HI

5E-075E-033E-022E-034E-023E-027E-043E-04NQ8E-03IE-078E-03

IE-01

Cs Soil concentration (rug/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inb) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

7]6johndeere*3/27.wk1

Table 22 Adult Resident Soil Exposure Doses, Hazard Quotients, and Excess LifetimeCancer Risks, South Scar Area, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent Ct SExD (O/D) SExD(Inh)Cancer Risk andHazard Quotients

Cancer EffectsArsenic 4.2Beryllium 0.84Cadmium 6.0Chromium 21Nickel 21Tetrachloroethene 0.048

2.0E-06l.SE-061.7E-056.7E-056.7E-051.9E-07

1.4E-102.8E-112.0E-106.9E-106.9E-101.6E-12

ELCR

4E-066E-06IE-093E-086E-10IE-08

IE-05

Non-Cancer EffectsAcetone 0.049Arsenic 4.2Barium 160Beryllium 0.84Cadmium 6.0Chromium 21Copper 38Cyanide 0.15Lead 80Mercury 0.07Nickel 21tPAHs 0.20Tetrachloroethene 0.048Zinc 100

4.5E-074.7E-061.2E-033.5E-063.9E-051.6E-045.5E-051.8E-068.3E-052.2E-071.6E-048.9E-074.4E-071.8E-04

3.8E-123.2E-101.2E-086.5E-114.6E-101.6E-092.9E-091.2E-116.2E-095.4E-121.6E-091.5E-113.7E-127.7E-09

m

4E-065E-032E-027E-044E-023E-02IE-039E-05

NQ7E-048E-032E-044E-059E-04

IE-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

716joh0doere*3/28.wkl

•Table 23 Adult Resident Soil Exposure Doses, Hazard Quotients, and Excess LifetimeCancer Risks, Landfill 1, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Cancer Effect*ArsenicBerylliumdufmivmChromiumNickelcPAHs -TetracbJoroethene

Ci

111.41352208.1

0.015

SExD (O/D)

5.3E-062.5E-063.6E-051.8E-046.4E-051.5E-055.9E-08

SExD(Inh)

3.6E-104.6E-114.3E-101.7E-096.6E-102.7E-105.0E-13

Cancer Risk andHazard Quotients

9E-06IE-053E-097E-086E-102E-043E-09

ELCR 2E-04

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadNickelSeleniumtPAHsTetrachloroetheneZinc

0.03411

1401.413523317

280201.19.8

0.015980

3. IE-071.2E-05l.OE-035.8E-068.4E-053.9E-044.8E-052.0E-042.9E-041.5E-041.2E-064.4E-051.4E-071.7E-03

2.6E-128.5E-101. IE-081. IE-10l.OE-094.0E-O92.5E-091.3E-092.2E-081.5E-098.5E-117.6E-101.2E-127.6E-08

HI

3E-06IE-022E-02IE-038E-028E-02IE-03IE-02NQ

7E-034E-O4IE-02IE-059E-03

2E-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/derma! exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

716johB<leerar3/29.wkI

Table 24Adult Resident Soil Exposure Doses, Hazard Quotients, and Excess LifetimeCancer Risks, Landfills 2 and 3, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent Cc SExD (O/D) SExD(Inh)Cancer Risk andHazard Quotients

Cancer EffectsArsenicBerylliumCadmiumChromiumMethylene chlorideNickelcPAHs

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideDibenzofuranLeadMercuryMethylene chlorideNickeltPAHsSeleniumTolueneXylenesZinc

IS1.31517

0.014256.2

0.1115

2601.3151726

6.01.888

0.0770.014

25301.4

0.0040.0046,000

7.2E-062.3E-063.7E-035.4E-055.5E-088.0E-051.2E-05

l.OE-061.7E-051.9E-035.4E-069.7E-051.3E-043.8E-057. IE-058.0E-069. IE-052.4E-071.3E-071.9E-041.3E-041.6E-063.7E-083.7E-081. IE-02

5.0E-104.3E-115.0E-105.6E-104.6E-138.3E-102.0E-10ELCR

8.5E-121.2E-092.0E-08l.OE-101.2E-091.3E-092.0E-094.6E-101.4E-106.8E-095.9E-121. IE-121.9E-092.3E-091. IE-103.1E-133.1E-134.6E-07

HI

IE-05IE-053E-092E-084E-107E-10IE-042E-04

IE-05IE-024E-02IE-03IE-013E-02IE-034E-03

NQ6E-028E-042E-069E-033E-025E-042E-072E-085E-02

3E-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to coil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

716johndeeror3/30.wkl

Table 25 Child Resident (age 0-6) Soil Exposure Doses, Hazard Quotients, and Excess LifetimeCancer Risks, Drum Storage/Hazardous Waste Storage Area, John Deere OttumwaWorks, Ottumwa, Iowa.

Constituent

Cancer Effects

ArsenicBerylliumCadmiumChromium3 ,3-DichlorobenzidtneMethylene chlorideNickelcPAHs

Non-Cancer Effects

AcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanide3,3-DichlorobenzidineLeadMelhylene chlorideNickeltPAHsSeleniumZinc

Ct

161.11470

0.390.003

230.47

0.07816

4001.11470431.0

0.39350

0.003231.71.2640

SExD (O/D)

1. IE-051.5E-062.6E-051.5E-045.6E-077.5E-094.9E-056.7E-07

2.3E-061.2E-049.9E-031.7E-053. IE-041.7E-033.7E-043.6E-056.5E-062.4E-038.8E-085.7E-042.8E-059.3E-066. IE-03

SExD (Inh)

1.8E-091.2E-101.5E-097.7E-094.3E-113.3E-132.5E-095.2E-11ELCR

l.OE-102. IE-085. IE-071.4E-091.8E-089.0E-085.5E-081.3E-095.0E-104.5E-073.9E-123.0E-082.2E-091.5E-098.2E-07

HI

Cancer Risk andHazard Quotients

2E-056E-069E-093E-073E-076E-112E-098E-063E-05

2E-05IE-012E-013E-033E-015E-01IE-022E-03

NQNQ

IE-063E-027E-033E-033E-02lE-t-00

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mgflcg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

7J6johndeere*3/31.wkl

Table 9fi Chad Resident (a8e ° ~ 6) .Soil Exposure Doses, Hazard Quotients, andExcess Lifedme Cancer Risks, Oil Spill Area, John Deere OttumwaWorks, Ottumwa, Iowa.

Constituent

Cancer EffectsArsenicBerylliumCadmiumChromiumNickel

Ct

4.81.96.71822

SExD (O/D)

3.2E-062.6E-061.3E-053.8E-054.7E-05

SExD(Inh)

5.3E-102. IE-107.4E-102.0E-092.4E-C5

Cancer Risk andHazard Quotients

6E-06IE-054E-098E-082E-09

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadNickelTolueneZinc

0.0064.81901.96.71817

0.452722

0.003860

1.8E-073.7E-054.7E-033.0E-051.5E-044.5E-041.5E-041.6E-051.9E-045.4E-048.8E-088.2E-03

ELCR

7.7E-126.2E-092.4E-072.4E-098.6E-092.3E-082.2E-085.8E-103.5E-082.8E-083.9E-121. IE-06

HI

2E-05

2E-064E-02IE-016E-03IE-01IE-014E-038E-04NQ

3E-024E-074E-02

5E-01

Cs Soil concentration (rag/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

71Cjotndeen«3/32.wkl

Table 27 Child Resident (age 0-6) Exposure Doses, Hazard Quotients and Excess LifetimeCancer Risks, South Scar Area, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Cucer Effect*

ArsenicBerylliumCadmiumChromiumNickelTetrachloroethene

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadMercuryNickeliPAHsTetrachloroetheneZinc

Ca

4.20.846.02121

0.048

0.0494.2160

0.846.02138

0.1580

0.0721

0.200.048

100

SExD (O/D)

2.8E-06ME -06I. IE-054.5E-054.5E-051.2E-07

1.4E-063.3E-054.0E-031.3E-051.3E-045.2E-043.3E-045.5E-065.6E-049.2E-075.2E-043.3E-061.4E-069.5E-04

SExD(Inh)

4.6E-109.2E-116.6E-102.3E-092.3E-095.3E-12ELCR

6.3E-115.4E-092. IE-071.1E-097.7E-092.7E-084.9E-081.9E-10l.OE-079.0E-112.7E-082.6E-106.2E-111.3E-07

HI

Cancer Risk andHazard Quotients

5E-065E-064E-099E-082E-096E-09IE-05

IE-053E-028E-023E-03IE-012E-019E-033E-04NQ

3E-033E-028E-04IE-045E-03

4E-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to coil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/R/D from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; (oxicity values were not available.

716johixleere*3/33.wkl

Table 28 Child Resident (age 0-6) Soil Exposure Doses, Hazard Quotients, and ExcessLifetime Cancer Risks, Landfill 1, John Deere Ottumwa Works, Ottumwa, Iowa.

Constituent

Cancer EffectsArsenicBerylliumO(dmi"mChromiumNickelcPAHsTetrachloroethene

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideLeadNickelSeleniumtPAHsTetrachloroetheneZinc

Cs

111.41352208.1

0.015

0.03411

1401.413523317

280201.19.8

0.015980

SExD (O/D)

7.3E-061.9E-062.5E-051.1E-044.2E-051.2E-053.8E-08

9.9E-078.5E-053.5E-032.2E-052.9E-041.3E-032.9E-046.2E-041.9E-034.9E-048.5E-061.6E-044.4E-079.3E-03

SExD(Inh)

1.2E-091.5E-101.4E-095.7E-092.2E-098.9E-101.7E-12ELCR

3.7E-121.2E-091.5E-081.5E-101.4E-095.7E-093.6E-091.9E-093. IE-082.2E-091.2E-101. IE-091.7E-121. IE-07

HI

Cancer Risk andHazard Quotients

IE-058E-069E-092E-072E-09IE -042E-092E-04

IE-059E-027E-024E-033E-013E-018E-033E-02NQ

2E-023E-034E-024E-055E-02

9E-01

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/derma! exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

Table 29

Constituent

Resident (age Q - 6) Soil Exposure Doses, Hazard Quotients, and ExcessLifetime Cancer Risks, Landfills 2 and 3, John Deere Ottumwa Works, Ottumwa, Iowa.

Ci SExD (O/D) SExD (Inh)

Cs Soil concentration (mg/kg).SExD (O/D) Exposure dose associated with oral/dermal exposure to soil (mg/kg/day).SExD (Inh) Exposure dose associated with dust inhalation exposure to soil (mg/kg/day).HI Hazard index (Sum of the hazard quotients [SExD/RfD from Table 64]).ELCR Excess lifetime cancer risk (SExD x SF from Table 64).NQ Not quantifiable; toxicity values were not available.

Cancer Risk andHazard Quotients

Cancer EffectsArsenicBerylliumCadmiumChromiumMelhylene chlorideNickelcPAHi

Non-Cancer EffectsAcetoneArsenicBariumBerylliumCadmiumChromiumCopperCyanideDibenzofuranLeadMercuryMelhylene chlorideNickel«PAHsSeleniumTolueneXylenesZinc

151.3IS17

0.01425

6.2

0.1115

2601.3151726

6.01.888

0.0770.014

25301.4

0.0040.0046,000

l.OE-051.8E-062.8E-053.6E-053.5E-085.3E-058.9E-06

3.2E-061.2E-046.4E-032. IE-053.3E-044.2E-042.2E-042.2E-043.0E-056. IE-04l.OE-064. IE-076.2E-045.0E-041. IE-051.2E-071.2E-075.7E-02

.7E-09

.4E-10

.7E-09

.9E-09

.5E-122.8E-096.8E-10ELCR

1.4E-101.9E-083.3E-071.7E-091.9E-082.2E-083.3E-087.7E-092.3E-091. IE-079.9E-111.8E-113.2E-083.9E-081.8E-095. IE-125.1E-127.7E-06

HI

2E-058E-06IE-088E-083E-102E-09IE-04

IE-04

3E-05IE-01IE-014E-033E-01IE-016E-03IE-02NQNQ

3E-037E-063E-02IE-014E-036E-076E-083E-011E+00

Table 30 Potable Surface-Water Exposure Dose (SWExD) and Hazard Quotient,Black Lake, Ottumwa, Iowa.

Constituent Csw SWExD Hazard Quotients

Non-Cancer Effect

BariumZinc

0.43 1.2E-020.038 1. IE-03

HI

2E-015E-032E-01

Crw Surface water concentration (mg/L).SWExD Surface water exposure dose (mg/kg/day) calculated using the values from GMSW-01.HI Hazard index (sum of the hazard quotients [SWExD/reference doses from Table 64]).

706jd/S2.wkl

Table 31 Calculated Blood Lead Levels in Children(Age 0-6)

SourceArea

Landfill 1

Landfill 2 and 3

Drum Storage/Hazardous WasteStorage Area

Oil Spill Area

South Scar Area

Medium

Soil/DustWater

Air

Soil/DustWater

Air

Soil/DustWater

Air

Soil/DustWater

Air

Soil/DustWater

Air

LeadConcentration(95% UCL)

280 mg/kg23 fig/L

0.021 jig/m3

88 mg/kg23 /ig/L

0.0066 j*g/mj

350 mg/kg23 fig/1

0.026 /ig/mj

27 mg/kg23 pg/L

0.002 jig/m3

80 mg/kg23 ;tg/L

0.006 ftg/mj

Blood Lead Levels*

Geometric Percent PercentMean Below Belowpg/dL 10 pg/dL 15 pg/dL

4.23 99.36 99.99

3.23 99.9t 100

4.59 98.78 99.97

2.91 99.98 100

3.19 99.95 100

• Calculated using the USEPA Model "LEAD4"

TMfd/MdM.fM

ATTACHMENT D

GLOSSARY OF EVALUATION CRITERIA

The following evaluation criteria were developed by EPA toaddress CERCLA statutory requirements and technical, cost, andinstitutional considerations. The evaluation criteria serve asthe basis for conducting the detailed analyses during theFeasibility Study and for subsequently selecting an appropriateremedial action.

THRESHOLD CRITERIA

OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

Alternatives are assessed as to whether they can provideadequate protection from risks above health-based levels posed bycontamination present at the site by eliminating, reducing, orcontrolling exposures.

COMPLIANCE WITH ARARS

The alternatives are assessed as to whether they attainapplicable or relevant and appropriate requirements of otherfederal and state environmental and public health laws or providegrounds for invoking a waiver.

PRIMARY BALANCING CRITERIA

LONG-TERM EFFECTIVENESS AND PERMANENCE

The magnitude of risk remaining after implementation of thealternative is evaluated. The adequacy and reliability ofcontrols used to manage treatment residuals or untreated wastesthat remain at the site are also assessed.

REDUCTION OF TOXICITY, MOBILITY AND VOLUME

The degree to which the alternatives employ treatment thatreduces toxicity, mobility, or volume is assessed.

SHORT-TERM EFFECTIVENESS

The alternatives are evaluated with respect to their effectson human health and the environment during implementation of thealternative.

IMPLEMENTABILITY

The technical and administrative feasibility of implementingan alternative and the availability of services and materials areevaluated.

COST

Direct and indirect capital costs and operation andmaintenance costs incurred over the life of the project areidentified.

MODIFYING CRITERIA

STATE ACCEPTANCE

Technical and administrative issues and concerns the statemay have regarding the alternatives are assessed.

COMMUNITY ACCEPTANCE

The issues and concerns of the public regarding thealternatives are assessed.

ATTACHMENT E

STATE LETTER OF CONCURRENCE

RECEIVED

JUL 0 5 1991PFMF SECTION.

Site: 7^>.

TERRY E. BRANSTAO. GOVERNOR DEPARTMENT OF NATURAL RESOURCESLARRY J. WILSON. DIRECTOR

June 27, 1991

Anne L. OlberdingSuperfund BranchU.S. EPA Region VD726 Minnesota AvenueKansas City, Kansas 66101

RE: John Deere Ottumwa Works Site

Dear Anne:

We have reviewed the Proposed Plan for the John Deere Ottumwa Works Site and concur with the preferredalternative for addressing the contaminated soil/fill material at the site. Please continue to keep us informedabout future site activities and schedules when they become known.

If you have any questions or comments regarding this matter please contact me at 515/281-4968 or KeithSchilling at 515/281-4117.

Sincerely,

Morris PrestonSupervisorSolid Waste Section

WALLACE STATE OFFICE BUILDING / DES MCHNES, IOWA 50319 / 515-281-5145 / TDD 515-242-5967 / FAX 515-281-8895