Consulting Engineers and Scientists

August 18, 1998

Mr. Alvin Kamu.s. Army Corps of EngineersOmaha DistrictCEMRO-ED-EA (Kam)215 North 17th StreetOmaha, NE 68102-4978

Subject: Final Record of Decision (Revision No. I)Soils OUNIIowa Army Ammunition Plant, Middletown, IowaContract No. DACW45-94-D-0044/0016Darza Project No. 5644JA

Dear Mr. Kam:

Harza Environmental Services, Inc. (Harza) is pleased to transmit eight copies of the final RecordofDecision for Soils OU#1 for the subject project, revised in response to Scott Marquess's recentcomments. An electronic copy of the text was E-mailed to Tim Howard at IOC on Friday (August14). We have provided separate copies to Scott Marquess (2 copies each) and Ken Herstowski (1copy each) at USEPA, Rodger Allison at IAAAP (12 copies each), and Derek Romitti at AEC (1copy each).

Please call me or Dave Scharre at (312) 831-3215, if we can be of assistance.

Very truly yours,

Robert P. Kewer, P.G.Vice President

RPK:le

Ene!.: As noted

ee: Mr. Scott MarquessMr. Ken HerstowskiMr. Rodger AllisonMr. Derek Romitti

Harza Environmental Services, Inc.Sears Tower 233 South Wacker Drive Chicago, Illinois 60606-6392Tel: (312) 831-3800 Fax: (312) 831-3999

RECORD OF DECISION

IOWA ARMY AMMUNITION PLANTSOILS OPERABLE UNIT #1

MIDDLETOWN, IOWA

DEPARTMENT OF THE ARMYCORPS OF ENGINEERS

OMAHA DISTRICTOMAHA, NEBRASKA

AUGUST, 1998

This document Is Intended to comply with theNational Environmental Polley Act of 1969

Iowa Army Ammunition PlantSoils QU#1, Record of Decision (Revision No.1)\Vl...IIPIIOIECTS-I~_~.VI~_wpcl August 14, 1998

TABLE'OF CONTENTS

List of Tables 3List ofFigures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4List ofAcronyms ; 5

1.01 DECLARATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7Site Name And Location . . . . . . . .. 7Statement ofBasis And Purpose 7Assessment ofThe Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7Description of The Selected Remedy ' . . . . . . . . . . . .. 8Statutory Determinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9Concurrence 11

2.0 DECISION SUMMARY . . . . . .. 122.1 Site Name, Location, and Description 122.2 Site History and Enforcement Activities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 162.3 Highlights of Community Participation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 172.4 Scope and Role of Operable Units 182.5 Summary of Site Characteristics 192.6 Summary of Site Risks 192.7 Description ofAlternatives 22

2.7.1 Alternatives for Explosives-Contaminated Soils 222.7.2 Alternatives for Explosives plus Metals Contaminated Soils 312.7.3 Alternatives For SVOC-Contaminated Soils 33

2.8 Summary of the Comparative Analysis ofAlternatives 342.8.1 Evaluation of Alternatives For Explosives - Contaminated Soils 352.8.2 Evaluation ofAlternatives for Explosives Plus Metals Contaminated Soils 372.8.3 Evaluation ofAlternatives for SVOC-Contaminated Soils 392.8.4 Environmental Consequences (NEPA Evaluation) 40

2.9 Selected Remedy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 412.9.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 412.9.2 Remediation Goals , 44

2.10 Statutory Determinations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 472.10.1 Protection ofHuman Health and the Environment 472.10.2 CompliancewithARARs 472.10.3 Cost Effectiveness 592.10.4 Use ofPermanent Solutions and Alternative Treatment Technologies 592.10.5 Preference for Treatment Which Reduces Toxicity, Mobility, or Volume 60

2.11 Documentation of Significant Changes 60

3.0 RESPONSIVENESS SUMMARY 613.1 Overview : . . . . . . . . . . . . . . . . . .. 613.2 Background on Community Involvement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 613.3 Summary ofPublic Comments and Agency Responses 63

Iowa Army Ammunition PlantSolis OU#1, Record of Oecision (Revision No.1)\V1...'IPROJECTS-'I5IU_~.VIODl5I44j• .nd02.wpd 2 August 14, 1998

Table ITable 2Table 3Table 4Table 5Table 6Table 7Table 8Table 9Table 10Table 11Table 12Table 13Table 14Table 15aTable 15bTable 15c

LIST OF TABLES

Source and Disposition of Soils . . . . .. 20CAMU Contents 21

Costs Alternative EIA: Incineration 24Costs Alternative Em Lttd 26Costs Alternative E2A: Composting 28Costs Alternative E2B: Bio-Slurry Treatment . . . . . . . . . . . . . . . . . . . . . . . . . .. 30Alternative Cost Comparisons Explosives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37Alternative Cost Comparisons Explosives plus Metals 39Alternative Cost Comparisons SY~CS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 40Selected Remedy Costs Explosives-contaminated Soils. . . . . . . . . . . . . . . . . . . . 42Selected Remedy Costs Explosives plus Metals Contaminated Soils 43Selected Remedy Costs SVOC-Contaminated Soils 44Soil Remediation Goals at 10-6 Risk Level Based on Ingestion/Dermal Contact . 45Soil Remediation Goals Based on Soil Leaching . . . . . . . . . . . . . . . . . . . . . . . . . ··46Compliance ofAlternatives with Location-Specific ARARs . . . . .. 48Compliance ofAlternatives with Chemical-Specific ARARs 50Compliance of Alternatives with Action-Specific ARARs . . . . . . . . . . . . . . . .. 55

Iowa Army Ammunition PlantSoils OU'1, Record of Decision (Revision No.1)IIH..lIP1tOJECTS-l'M44_aNe«jIVlOCMe44jIJlldll2....... 3 August 14, 1998

Figure 1Figure 2Figure 3

LIST OF FIGURES

Site Location Map 13Drainage Basins and Site Features Map 14CAMU Location 15

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)',"""lIPIlOJECTSol-.--,VlOD'6l44Ja_.wpd 4 August 14, 1998

ATLARARBDATBLRACAACAMUCERCLACFRCOC2,4-DNTEPAggldscmgldscfHALIAAAPI.A.C.IDNRIEQAkgLDRLITDMCLMCLGmglkgmgILMglyrmremMSWLFNAAQSNCPNESHAPNPDESNRLOUPAHPCBpCilLpH

ACRONYMS

Alternate Treatment LevelApplicable or Relevant and Appropriate RequirementBest Demonstrated Available TechnologyBaseline Risk AssessmentClean Air ActCorrective Action Management UnitComprehensive Environmental Response, Compensation and Liability ActCode'ofFederal RegulationsContaminant of Concern2,4-DinitrotolueneU.S. Environmental Protection AgencyGramsGrams Per Dry Cubic Meter at Standard ConditionsGrams Per Dry Cubic Feet at Standard ConditionsHealth Advisory LevelIowa Army Ammunition PlantIowa Administrative CodeIowa Department ofNatural ResourcesIowa Environmental Quality ActKilogramLand Disposal RestrictionLow Temperature Thermal DesorptionMaximum Contaminant LevelMaximum Contaminant Level GoalMilligrams Per KilogramMilligrams Per LiterMegagrams Per YearMilliremsMunicipal Solid Waste LandfillNational Ambient Air Quality StandardNational Contingency PlanNational Emission Standard for Hazardous Air PollutantNational Pollutant Discharge Elimination SystemNegligible Risk LevelOperating UnitPolynuclear Aromatic HydrocarbonsPolychlorinated BiphenylPico Curies Per LiterUnit ofMeasure for Hydrogen Ion Concentration

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\VI..1IPRO.IECTS-1158U_-'VI~._Z.wpd August 14, 1998

ppmRCRARDXRIlFSRODSDWASVOCSWMUTBCTCLP1,3,S-TNBTNT2,4,6-TNTTSCAT/SIDU.S.C.USTJlglm3

ACRONYMS (Continued)

Particulate Matter (particles with an aerodynamic diameter less than or equal to anominal 10 micrometers)Parts Per MillionResource Conservation and Recovery Act1,3,5-Trinitro-l ,3,5-triazacyclohexaneRemedial InvestigationIFeasibility StudyRecord ofDecisionSafe Drinking Water ActSemiVolatileSolid Waste Management UnitTo Be ConsideredToxicity Characteristic Leaching Procedure1,3,5-TrinitrobenzeneTrinitrotoluene2,4,6-TrlnitrotolueneToxic Substances Control ActTreatmentlStoragelDisposalUnited States CodeUnderground Storage TankMicrograms Per Cubic Meter

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)Wt..IIPIIOJECTSoI15N4_IlNllU4jaWlOO'6M4/a_.wpd 6 August 14, 1998

1.0 DECLARAliON

Site Name And Location

Iowa Army Ammunition Plant (IAAAP)Soils Operable Unit #1 (OU#I)Middletown, Iowa

Statement of Basis And Purpose

This decision document presents the selected remedial action for the Soils Operable Unit #1 at theIowa Army Ammunition Plant (IAAAP) in Middletown, Iowa. The remedial action was chosen inaccordance with the Comprehensive Environmental Response, Compensation and Liability Act(CERCLA), as amended by the Superfund Amendments and Reauthorization Act (SARA), and tothe extentpracticable, the National Contingency Plan (NCP). This decision is based on informationin the site Administrative Record file, which is located in the following information repositories:

Iowa Army Ammunition PlantVisitor Reception AreaBuilding 100-101Middletown, Iowa 52683-5000(319) 753-7710

Danville City Hall105 W. ShepardDanville, Iowa 52623(319) 392-4685

Burlington Public Library501 N. Fourth StreetBurlington, Iowa 52601(319) 753-1647

The U.S. Army (Army) has coordinated selection of this remedial action with the U.S.Environmental Protection Agency (EPA). The Army is the lead agency for implementing theremedial action at the IAAAP. As the support agency, the EPA oversees the cleanup activitiesconducted by the Army to ensure that requirements ofCERCLAISARA, the NCP, and the FederalFacilities Agreement between the Army and theEPA have been met. EPA concurs with the selectedremedy. The State oflowa has not participated in the review ofCERCLA clean up activities at theIAAAP and has declined to commentupon theselected remedy presented in this Record ofDecision(ROD).

Assessment of The Site

Actual or threatened releases of hazardous substances from this site, if not addressed byimplementing the response action selected in this Record ofDecision, may present an imminent andsubstantial endangerment to the public health, welfare, or the environment.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\I1..1IPROJECTS-11S1U_~.\R~"" 7 August 14, 1998

Description of The Selected Remedy

The IAAAP has been divided into a Soils OU (OU#l), a Groundwater OU (OU#3), and anInstallation-Wide OU (OU#4) to facilitate management ofcontamination at the site. The Soils OU#laddresses contamination in the soils. The Groundwater OU#3 addresses contamination ofgroundwater within the IAAAP boundaries and potentially off-site. The Installation-wide OU#4addresses other unacceptable risks not addressed in either OU#l or OU#3. The RemedialInvestigation for the Soils OU is complete and has been followed by a Feasibility Study (FS).Additional data have been requested by the EPA to complete the investigation ofthe Groundwater OUand the Installation-Wide OU.

An interim remedial action for the Soils OU#l called for the temporary stockpiling, for futuretreatment, of the most highly contaminated soils and the permanent disposal of the remainingcontaminated soilsfrom various sites at the IAAAP. The Interim Action ROD specified that the mosthighly contaminated soils will be stockpiled in the on-site Corrective Action Management Unit(CAMU), which was constructed to specifications which meet Resource Conservation and RecoveryAct (RCRA) Subtitle C landfill requirements. The remaining contaminated soils will be permanentlydisposed in either the on-site Soil Repository, which is also constructed to RCRA Subtitle C landfillspecifications, or the on-site Inert Landfill. A synthetic liner (HDPE) and GCL cover system willcover contaminated soils placed in the Soil Repository. The cover for the Inert Landfill is of similardesign to the Soil Repository cover, absent the GCL. Soils in both the Soil Repository and InertLandfill will remain on-site for long-term management.

The remedial action presented in this Record of Decision is intended to provide for treatment andultimate disposal of soils, which are being temporarily stockpiled in the CAMU as a result of theinterim action. Soils stockpiled in the CAMU are managed based on the nature· ofcontamination:

• Explosives-contaminated soils

• Explosives plus metals contaminated soils

• SVOC-contaminated soils

Any long-term monitoring needed to evaluate the performance of the remedy, land usage restrictionsas required, a closure plan to address the CAMU, and the identification and inclusion of any othercontaminated areas requiring remediation will be addressed in the Installation-Wide OU #4.

The major components of the selected remedy include:

Explosives-Contaminated Soils

• Excavate explosives-contaminated soil from the CAMU and transport it to a temporary treatmentfacility on-site.

• Screen, shred and blend the soil to produce a uniform feed material.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)

8August 14,1998

• Process the blended soil through a mobile direct-fired low temperature thermal desorption (LTID)unit (Selected Remedy) or a temporary Biological Treatment unit (Contingent Remedy).

• Following confirmation sampling, dispose of treated soil according to the following criteria:

A. For soils with cumulative risks less than 10-6, in compliance with LDRs, and exceedingSummers model remediation goals, dispose in the Soil Repository or under another syntheticlandfill cap on-site.

B. For soils with cumulative risks less than 10-6, in compliance with LDRs, and satisfyingSummers model remediation goals, dispose on IAAAP property in an appropriate mannerprotective of human health and the environment. For Biotreated soils, treatment residualsmust also be shown to be non-toxic or not bioavailable at levels posing a threat to humanhealth or the environment.

Explosives Plus Metals Contaminated Soils

• Excavate explosives plus metals contaminated soil from the CAMU and transport it to a temporarytreatment facility on-site.

• Screen, shred and blend the soil to produce a uniform feed material.

• Process the blended soil through a temporary solidification/stabilization facility.

• Following sampling to confirm compliance with TCLP based remediation goals, dispose oftreatedsoil on-site in the Soil Repository or under another synthetic landfill cap.

SVOC-Contaminated Soils

• Excavate SVOC-contaminated soil from the CAMU.

• Transport the soil to a commercial waste treatment and disposal facility off-site.

Statutory Determination

The selected remedy is protective of human health and the environment, complies with Federaland State of Iowa requirements that are legally applicable or relevant and appropriate to theremedial action, and is cost-effective. This action utilizes penrianent solutions and alternativetreatment technologies to the maximum extent practicable for this site and satisfies the statutory

. preference for remedies that employ treatment to reduce toxicity, mobility, or volume as aprinciple element.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)

9August 14, 1998

Becausethis remedy may result inhazardous substances remainingon-siteabovehealthbased levels,depending upon the method oftreatment selected, a reviewwill be conducted within five years aftercommencement of remedial action to ensure that the remedy continues to provide adequateprotection ofhuman health and the environment. This review may be based on or incorporated intoa similar review which is required to be conducted within five years after commencement of theSoils OU#1 interim remedial action that disposes contaminated soil in the on-site Soil Repositoryand Inert Landfill.

Da~/9 ~?r

tten t Colonel, OD

Commander, Iowa AAP

Den s Grams, P.E.R ional AdministratorU.S. Environmental Protection AgencyRegion VII

Da~p¢8

~&.jormME:Wiiii81llS

Major General, U.S. ArmyChief of Staff, U.S. Army Material Command

Date

Iowa Army Ammunition PlantSolis OU#1, Record of Decision (Revision No.1)IVl...lIP11O.1ECT$.ll51«_-,llI-,-'wpd 10 August 14, 1998

Installation/MSC Legal Advisor

Iowa Anny Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\H...IIPItOJECTS-I__III5I44I'VI~_.wpd 11

Date

Date

Date

August 14, 1998

2.0 DECISION SUMMARY

2.1 Site Name. Location. and Description

The IowaArmy Ammunition Plant (IAAAP) is a load, assemble, and pack (LAP) munitions facilitylocated in Middletown, a rural area of eastern Iowa, 10 miles west of Burlington in Des MoinesCounty, and approximately nine miles northwest of the Skunk and Mississippi Rivers (see FigureI). Croplands comprise about 60 percent of the county; the remaining area is composed of 10percent urban use, eight percent pasture use, and 22 percent woodland or idle land. The IAAAP islocated on about 19,000 acres. Approximately 8,000 acres are leased for agricultural use, about7,500 acres are forested, and the remaining area is used for administrative and industrial operations.Deerhunting is regulated at the IAAAP through theuseofpermits. Approximately 41 housing unitsand 112 acres ofland outside ofthe operating areas ofthe plant have been transferred to the City ofMiddletown. Two housingunits remainon-site and are currently occupiedbymilitary personnel andtheir families.

The northern area of the IAAAP consists of gently undulating terrain. The central portion ischaracterized by rolling terrain dissected by a shallow drainage system, while the southern area ofthe site contains drainage ways with steep slopes down to the creek beds. Elevations within theIAAAP range from 730 feet above mean sea level in the north to 530 feet in the south. There arefour principal aquifers in Des Moines county. These include a shallow or sumcial aquifer (driftaquifer) in unconsolidated Recent Pleistocene sediments, and bedrock aquifers occurring in theMississippian, Devonian, and Cambro-Ordovician units.

The IAAAP contains four watersheds. Brush Creek drains the central portion ofthe site, exits at thesoutheastern boundary, and flows into the confluence of the Skunk and Mississippi Rivers. Thecreek's flood plain at the southern boundary of the site is estimated to be 200 feet wide. SpringCreek drains the eastern portion of the site, exits at the southeastern corner, and flows off sitedirectly into the Mississippi River. The creek's flood plain at the southeastern boundary ofthe siteis estimated to be 400 feet wide. Long Creek drains the western portion ofthe IAAAP, exits at thesouthwestern boundary, andjoins the SkunkRiverjust south ofthe site. The Skunk River then flowsinto the Mississippi River. The Long Creek drainage way has been dammed near the center of thesite to create the 85-acre George H. Mathes Lake. Use ofthis lake by the plant as a water source wasdiscontinued in January 1977. An open recreation area and a boat ramp used by fishermen arepresent at the lake. North ofMathes Lake is the 7-acre Stump Lake, which was built to serve as asediment control for Mathes Lake. The flood plain of Long Creek is widest (500 feet) at thesouthern plant boundary. The Skunk River is located south of the IAAAP, bordering the site'sperimeter on the southwest corner. The Skunk River provides year-round recreational use. Figure2 provides a site plan ofthe IAAAP.

The CAMU is located along the western edge ofthe Inert Landfill at IAAAP as illustrated in Figure3. The area is part of the Long Creek watershed.

Iowa Army Ammunition PlantSoils OUt#1, Record of Decision (Revision No.1)1'I1...1IPROJECTS-1151«_d'6I44111RODWI44jollld02.wpd 12 August 14. 1998

I..,...

_-.JL- ..>.:. ~_Figure 1

SITE LOCATION MAPSOILS au No.1 RECORD OF DECISION

IOWA ARMY AMMUNITION PLANTMiddletown,lowaI--JARZA Consulting Engineers and Scientists

SOURCE: Minnesota's Geology~

"1:'"~'---------------------------_.....

~ ROAD NAME

••_ •• _ •• _ ••- PLANT PROPERTY BOUNDARY

- __III••_IIIF... DRAINAGE BASIN BOUNDARY

----RIVER I STREAM

NOTE:1. INCLUDES INERT LANDFILL, SOIL REPOSITORY,

ANDCAMU.

LEGEND:

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II

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I

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Figure 2DRAINAGE BASINS AND SITE FEATURES MAP

SOILS OU No.1 RECORD OF DECISIONIOWA ARMY AMMUNITION PLANT

Middletown, Iowa

Scale O~~!!!2;;05iiO~O;;;;;;;;;;_4;i;i0zO!!!O~!!!!!!!6050;;ii0i;;;;;;;;;;;;;;;ii8;ii1000 Feet

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• :2 I I A 0""'7 AII ...~ Consulting Engineers and Scientists~L- ....... -------__-------------~

Scale 0 500 Feet,~~~~

Figure 3

CAMU LOCATIONSOILS OU NO.1 RECORD OF DECISION

IOWA ARMY AMMUNITION PLANTMiddletown, IowaI--IARZA Consulting Engineers and Scientists

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2.2 Site History and Enforcement Activities

TheIAAAP produced munitions forWorld WarII from theplant's inception in September 1941 untilAugust 1945, and munitions for military activities in southeast Asia in the 1960s and early 1970s.Activities at the IAAAP continued ata reduced level during peacetime. The plantwas operatedfrom1941 - 1946 by Day & Zimmerman Corporation. Theformer Atomic Energy Commission operatedat Line I from 1948 through mid-1975, at which time operation reverted to u.S. Army (Army)control. The Army continues to own the IAAAP, which has been operated by the private contractorMason & Hanger Corporation since 1951. The IAAAP currently is operating to load, assemble, and

. pack(LAP)munitions, includingprojectiles, mortarrounds, warheads, demolition charges, anti-tankmines, anti-personnel mines, and the components ofthese munitions, including primers, detonators,fuses, and boosters. Since the installation is an activeproductionplant, inactive lines are maintainedon a standby status or leased to other contractors.

The primary source ofcontamination at the site is attributable to past operating practices in whichexplosives-contaminated wastewaters and sludges were discharged to uncontrolled, on-site lagoonsand impoundments. Additional sources of contamination include open burning of explosivesmaterials and munitions, and landfillingofwastematerial. Process wastewaters currently are treatedand recycled, while only a small portion ofthe treated wastewater, containing residual explosivesand other contaminants regulated under the plant's NPDES permit, is discharged to surface.Pink/red wastewaters from trinitrotoluene (TNT) operations are a listed hazardous waste (K047)according to the Resource Conservation and Recovery Act (RCRA).

The U.S. Environmental Protection Agency (EPA) added the IAAAP to the National Priorities List(NFL) in 1990. The NPL is the EPA's list ofsites that appear to pose the greatest threat to humanhealth and the environment, based on the site assessment process. The Department of Defense(DOD) has established the Defense Environmental Restoration Account to address sites under theComprehensiveEnvironmental Response, Compensation and Liability Act (CERCLA), as amendedby the Superfund Amendments and Reauthorization Act (SARA), that are within the responsibilityof the DOD. The Army, as an agency within the DOD, is the lead agency for implementing theinterim remedial action at the IAAAP. As the support agency, the EPA oversees cleanup activitiesconducted by the Army to ensure that the requirements of CERCLAISARA and the NationalContingency Plan (NCP) have been met. The EPA and the Army signed a Federal FacilitiesAgreement (FFA) for site cleanup, which became effective December 10, 1990, following publiccomment. The FFA provides a framework for CERCLA response actions to be performed at thelAAAP, including the investigation and cleanup ofcontamination. The State ofIowa has declinedto participate as a signatory party to this FFA.

Numerous investigations have been conducted at the site by the Army from 1975 to the present toinvestigate soil and groundwater contamination. Based on data collected at the site, the Army hasinitiated response actions at the IAAAP to address soil contamination at several areas across thelAAAP. These actions are documented in several Action Memoranda from 1995 through 1997 andan Interim Action Record of Decision (ROD) signed by EPA in March 1998. During removal

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actions completed at the formerLine 1impoundment andthe Line 800pinkwaterlagoon, cumulativerisk levels were determined for soils at each sourcebased on sampling and analysis for contaminantsofconcern. Soils with the highest contaminant concentrations were excavated and stockpiled in alined storage facility known as a Corrective Action Management Unit (CAMU) for subsequenttreatment. Moderately contaminated soils were excavated and disposed in an on-site SoilRepository. Lightly contaminated soils were disposed under the synthetic cap ofthe Inert Landfillon-site. Excavation of materials from the Line 1 Impoundment and the Line 800 Lagoon wascompleted in August, 1997. The remaining areas ofsoil contaminationwill be excavated and placedin the CAMU or in the Soil Repository according to the March 1998 Interim Action ROD.

2.3 Highlights of Community Participation

The RIfFS and Interim Action Proposed Plan for the Soils OU were released to the public inNovember 1996 and May 1997, respectively. These documents were made available to the publicin both the administrative record and the site information repositories. The notice of availabilityfor the Interim Action Proposed Plan was published in the Burlington Hawk Eye on May 28, 1997.A public comment period was held from May 28, 1997 to June 30, 1997. In addition, a publicmeeting was held on June 5, 1997 at the Danville Community Center. At this meetingrepresentatives from the Army and EPA were available to the public to discuss concerns, acceptcomments, and answer questions regarding the preferred alternative presented in the Interim ActionProposed Plan. There were no written or verbal comments regarding the Interim Action ProposedPlan submitted to the Army at this meeting or during the comment period, thus a ResponsivenessSummary was not included in the Interim Action ROD.

The Proposed Plan for final action for the Soils OU #1 was released to the public on June 20, 1998.This document was made available to the public in both the administrative record and the siteinformation repositories. The notice of availability for the Proposed Plan was published in theBurlington Hawk Eye on June 20, 1998 and later in the Ft. Madison Daily Democrat. A publiccomment period was held from June 20, 1998 to July 19, 1998. In addition, a public meeting washeld on July 9, 1998 at the pzazz Best Western Motor Inn in Burlington, Iowa. At this meetingrepresentatives from the Army and EPA were available to the public to discuss concerns, acceptcomments, and answer questions regarding the preferred alternative presented in the Proposed Plan.All comments received by the Army and the USEPA during the public comment period, includingthose expressed at the public meeting, are addressed in the Responsiveness Summary which isattached to this document.

An IAAAP Restoration Advisory Board (RAB) has been established to enable the community andrepresentatives ofgovernment agencies to meet and exchange information aboutthe IAAAP's environmentalcleanup program and to provide the community an opportunity to review progress and participate in dialoguewith decision makers. The RAB was organized in mid-l997 and has held public meetings generally monthly.This decision document presents the selected remedial action for the Soils OU#1 at the IAAAP inMiddletown, Iowa, chosen in accordance with CERCLA, as amended by SARA and, the extentpracticable, the National Contingency Plan. The decision for this site is based on the administrative

Iowa Army Ammunition PlantSoils QU#1. Record of Decision (Revision No.1)\\HHoIIPROlECTS-115N4__.,.VlOIl'6I4",_,wpd 17 August 14, 1998

record.

2.4 Scope and Role of Operable Units

Due to the complexity ofthe problems associated with the IAAAP, the site has been divided intothree OUs to facilitate project management. These are the:

• Soils OU (#1), to address contamination in the soils.

• Groundwater OU (#3), to address contamination of groundwater within the IAAAPboundaries and potentially off-site.

• Installation-Wide OU (#4), to address closure of the CAMU, institutional controls,previously unaddressed areas ofsoil contamination, VOC-contaminated media, ecologicalrisks, long-term monitoring requirements, and any other unacceptable risks which may beidentified and not addressed in either OU #1 or OU #3.

OU #2 was originally established for the soils interim action, but was subsequently merged into OU#1 for simplicity and completeness.

The Removal Actions and the Interim Action for the Soils OU #1addressed the contaminated soilsin a number of areas at the IAAAP. These areas posed an unacceptable threat to human health andthe environment due to risks from possible ingestion or dermal contact with soils, and due topotential contaminant leaching from soil to groundwater. Under these actions, soils contaminatedat levels posing a potential health threat, or acting as a potential source ofcontinuing groundwatercontamination, were contained in on-site landfill facilities. Highly contaminated soils werestockpiled in the CAMU for subsequent treatment, while moderately and lightly contaminated soilswere disposed permanently in a Soil Repository or beneath an Inert Landfill cap on-site. Potentialgroundwater impacts as measured by Summer's model and Land Disposal Restrictions (LDRs)werealso considered in identifying principal threats and low-level threats. This ROD provides fortreatment and ultimate disposal of the soils representing the principal threat at the IAAAP whichhave been stockpiled in the CAMU under the Soils OU #1. Substantial on-site activities associatedwith treatment will commence within 15 months ofthe physical completion ofthe interim remedialaction for the Soils OU#1. The action specified in this ROD is intended to be the final action underthe Soils OU (OU # 1) at IAAAP. Separate RODs will be issued for the Groundwater OU #3 andthe Installation-Wide OU #4 to provide an opportunity for the public to comment on cleanup plansunder consideration for those areas.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\V1...'Il'IIOJECTS-,__~.lIIClOWI44jI_"'" 18 August 14, 1998

2.5 Summary of Site Characteristics

Table 1summarizes the sources and quantities ofsoils removed under Removal Actions or InterimAction. Only the soils stockpiled in the CAMU are intended to receive additional treatment underthis ROD prior to fmal disposal. Table 2 identifies the individual sources, quantities, andcharacteristics ofsoils stockpiled in the CAMU. Soils identified in this table are characterized asfollows:

• Approximately 9,000 cubic yards of soil contaminated with explosives.

• Approximately 600 cubic yards ofsoil contaminated with explosives plus metals.

• Approximately 200 cubic yards ofsoil contaminated with semi-volatile organic compounds(SVOCs).

The Interim Action ROD identified approximately 300 cubic yards of soil to be excavated andstabilized because ofthe presenceofradionuclides. However, there is currently uncertainty whetherthesesoils are contaminated above naturally occurringlevels. Ifexcavation and treatmentultimatelyis required, these soils will be addressed later under a separate OU or response action.

Excavation ofmaterials from the Line 1Impoundment and the Line 800 Lagoon was completed inAugust, 1997. The remaining sources will be excavated and placed in the CAMU or in the SoilRepository according to the March 1998 Interim Action ROD. Volumes and concentrations ofcontaminated soil to be removed from these remaining sources are estimated based on limited sitesampling. The actual volumes and characteristics will be detennined based. on additionalconfmnationsampling during theInterim Action. Actualvolumes andcharacteristics mayvaryfromthose shown in Table 2. However, since the greatestvolume ofsoil to be treated originated from theLine 1Impoundment and the Line 800 Lagoon excavation, which has already been completed, thetotal volumes and characteristics presented in Table 2 are considered representative for the purposesof this ROD.

2.6 Summary of Site Risks

During the RIfFS, an analysis was conducted to estimate the health or environmental problems thatcould result ifthe soil contamination at IAAAP was not cleaned up. This analysis is referred to asa Baseline Risk Assessment (BLRA). In conducting the BLRA, the focus was on the health effectsthat could result from direct exposure to contaminants as a result ofthe soil coming into contactwiththe skin, or from direct ingestion of the soil. The analysis identified explosives as the majorcontaminants of concern. Metals and semi-volatile organic compounds (SVOCs) were alsoidentified as contaminants of concern at certain sites. The BLRA for the IAAAP identifiedunacceptable risk based on afuture commerciaVindustriallanduse setting due to possible incidental

Iowa Army Ammunition PlantSolis OU#1, Record of Decision (Revision No.1)\\H...'IPI\OJECTS-'-'_~lIIllDW1«j.J1IClO2."'" 19 August 14, 1998

TABLE 1SOURCES AND DISPOSITIONS OF SOILS

SOURCE DISPOSmONINERT

LANDFILLCAMU SOIL REPOSITORY CAP TOTAL

Criteria: A B C DRemoved Under Removal Action (Currently stockpiled)Une 1 Impoundment 618 1,234 6,418 8,270Une 800 Lagoon 6,803 12,133 55,800 74,736

Subtotal (cubic yards) 7,421 13,367 62,218 83,006Removed Under Interim Action (To be removed)Line 1 (R01) 402 3,960 1,874 6,236Line 2 (R02) 86 452 1,117 293 1,948Line 3 (R03) 1,395 175 1,086 837 3,493Une3A(R04) 327 442 0 1,267 2,036Unes 4MB (R05) 0 0 153 0 153Lines 5MB (R06) 187 244 0 300 731Line 6 (R07) 0 401 44 0 445Une8 (R09) 0 0 476 0 476Une9 (R10) 0 0 469 0 469Unr 800 (R11) 0 1,095 117 113 1,325East Bum Pas (R12) 140 293 0 .20,978 21,411Demolition Area (R15) 0 0 753 0 753West Bum Pads (R24) 0 0 1,112 339 1,451North Bum Pad (R25) 0 41 0 0 41Roundhouse (R28) 0 599 0 0 599

3,742 9,287 26,001Subtotal (cubic yards) 2,537 39,030 • 41,567

Total (cubic yards) 9,958 52,397 62,218 124,573

Criteria:A (risk >10-5): Place in CAMUB (risk between 10-6 & 10-5): Place in Soil RepositoryC (risk <10-6, wI metals): Place in CapD (risk <10-6, wlo metals): Place in Cap

• Inert Landfill not available for additional fill

Data taken from: Focused Feasibility Study, Appendix E (5-8-98)

\\HE8-1\Projects-1\5644_aI1\5644ja\ROD\Tables\Xls-sheet 1August 14, 1998

SOURCE

EXPLOSIVES:

TABLE 2CAMU CONTENTS

VOLUME RDX TNT TH8 DNT lud AnenIc DIbenzof. BenzO(.roi. _&a ...........

,cyt !'conc. mglkat '..... lbt I,cone. malkat 'mISS, lb. I,cone, mgIkg ' ....... lbt !'conc. malka ,..... Ibt i ,cone:, "'IIkeJ (mla. lb. ,cone. maika, (man, Ib' liconc. maIIra ,......... 1,_ -'It.., 1...... 1111 (cone, mglki ,.... lIIt(conc:,lIIIIIIca 1...... 1111 1,_.-... (..... II.

-.----.... f------ -·--+----+------t----I

-----4..----.;--------- - ...----+----4-----t------f---

lk1e 1 811 ..08 881 3.392 5.680

Une800Lagoon _ 8803 .~ :~ __ 3.392 82.305 1-_ 55.9 1.027

B-2.Q51DownS!!np2·1~7 ..7 5500 891 1..00 178 350 .... --f-----.I----;-----I-----~---_J_----___J.---+_--'---1_.---f-----+--.--+- -+ _

H..~~-~.~~~_._- -- --- --. ----- ---~? -.~~~~ -- -_.--~ -.----!~.-----!~ ----.. -.-----------------------. -----..- -- --r--.------ ---------'----- f-._._ .. --- . . ._._---- -.---. ..----.-- ..--.... -------.-

fiJ~~~!J5-!'se~~__ . 650 64." 1.1.~ 42580 ..._ ?~.72~ 2~~ __ . _421 " _...... _ .. .__, .. _. . .. •... . _. ., . . _.. _ . . .• __ .... _•. _. . ._.. - ._.

8:~~~. _.._. .. _... . .. ~~~ _•._~16.~~ __._ --!t! _---!!!~~~Jr---~r_.._.' _~ .. --...!!S 10 . ._____ __ .. . . __ .

B-3-~~~E BuiId!~ . _?22 . ...~ __...!~~. _.__~~ _~362 ~ -._ .. _ . .J.~ ---._~ -. --'--- ._ - - - -.-t---------t----+------4-----.-~~:_~_~_._...._ ._. ..._. _ _ _ !~~ ... __ .. _~-~!._. .1 .....__.~~~:~~ .. __...~.~~ .. _ ..._._... ....__ . .__ ... __ ._.. . ...._~--._~---. . __"' . .. . __

~~~~ ~~-.m ~OO~ ~~ ~m~ 1~m . . n ~ __.~~---~--~~--~---_+--~~---~---I~i~) .._ .... _ _ 8~8Q4 . _. _.~~1. ~~! ._._._.!e!.~ _~!!!.~~ ..__ .. ..10- __ .~.!..~ ._. _ .__._.~ __. 1.17" __. _. ._. ---a.__ ---••--.f--.----.-- 1--- • .. __ •• . __ -. .__ . __ ---...--f--_. __._._ . I---.--.f---.------f----.-.---

EXPLOSIVES. METALS:

B-3-05-2ISE Comer

fl-3A.G5.1JS SIde

1VOCe:

RADIONUCUDEI:

8-1-70-tISEeon.

TOTAL 111

188 13.n 7 34085.87 17.108 380 181 18.5 8 2978.5 1.496 79

95 35.7" 9 17000 22.318 23000 5.900 210 54 1204 309

327 2647.5 2,337 5140 ",538 1157 1.483

25 7!5000 5.083 250 17 1829 110

833 4,330 7."18 ~732 "3.178 3.551 8.080 1,'78 3.378 40

217 tOO 5 3 eo 47 100

115 0.• OJ119 1.51 OJ304 1.2 1

',151 1117 • .ou .... 2SUU 243 I"'" ... 1.231 121 3.371 1.1 40 2.2 • 0.1 1.7 47 • 1.14

(1) Cone. • -"-.,,

ingestion and dermal contactwith contaminated soils. The BLRA also identified unacceptable riskassociated with potential consumption of contaminated groundwater on-site. Site soils have beendetermined to beacting as acontinuingsourceofgroundwatercontaminationatunacceptablelevels.

The BLRA provided the basis for the response actions that determined what soils were to beexcavated and eitherdisposed in the Soil Repositoryofthe InertLandfill or stockpiled in the CAMUfor subsequent treatment Under the CERCLA, containmentoflow level threats is acceptablewhiletreatment ofprincipal threats to permanently reduce contaminant toxicity, mobility and volume ispreferred. Principal threats are defmed as the most highly contaminated, most toxic, and mostmobile sourcematerials. UndertheInterim ActionROD, highly contaminated soils (cumulative riskgreater than 10.5) were considered to represent the principal threat and therefore were stockpiled inthe CAMU for treatment at a later date. Moderately contaminated soils (cumulative risk between10.5 and 10.6) and lightly contaminated soils (cumulative risk less than 10-6) were considered topresent low-level threats and thereforewere permanently disposed in the Soil Repository or the InertLandfill cap. Potential groundwater impacts as measured by Summer's model and LDRs were alsoconsidered in identifying principal threats and low-level threats.

The BLRA presents risks associated with the "baseline" condition at the site prior to execution ofany response actions. For the purposes of this ROD the "baseline" conditions as defmed in theBLRA no longer exist because response actions been taken or are planned to abate certain site risks.

2.7 Description of Alternatives

Separatealternativesweredevelopedforsoils contaminatedwithexplosives, soils contaminatedwithexplosives and metals, and soils contaminated with SVOCs. The Superfund program requires thatthe"no-action" alternativebe considered as abaselinefor comparisonofother alternatives. The"no­action" alternative was evaluated as part ofthe OU #1Interim Action, which is the precursor to thisFinal Action for au # 1. Since the Final Action is intended to address treatment of the principalthreat, the "no-action" alternative was not considered further.

2.7.~ Alternatives for Explosives-contaminated Soils

Approximately 9,000 cubic yards of soil are identified as being contaminated solely withexplosives, without metals contamination exceeding LDRs. Alternatives for treating soilscontaminated solely with explosives are as follows:

Alternative E1A: Incineration

This alternative consists ofon-site incineration, with disposal ofincinerator ash in an on-sitelandfill; because metals concentrations in the soils are low, it is assumed that additionaltreatment of incinerator ash (i.e., solidification/stabilization) will not be required. Theprincipal elements of this alternative are as follows:

Iowa Army Ammunition PlantSoils CU#1, Record of Decision (Revision No.1)\\H_IIP"OlEc:rs.I_4_.-"Vl~ 22 August 14, 1998

• Excavate explosives-contaminated soil from the CAMU and transport it to atemporary treatment facility on-site.

• Screen, shred and blend the soil to produce a uniform feed material.

• Process the blended soil through a mobile rotary-kiln incinerator to achieve disposalcriteria outlined below.

• Following confirmation sampling, dispose oftreated soil (ash) on-site either:

a. For soils with cumulative risk less than 10-6, in compliance with LDRs, andexceeding Summers model remediation goals, dispose in the Soil Repositoryor under another synthetic landfill cap on-site.

b. For soils with cumulative risk less than 10-6, in compliance with LDRs, andsatisfying Summers model remediation goals, dispose on IAAAP property inan appropriate manner protective ofhuman health and the environment.

Incineration is the primary treatment technology used under this alternative. Incineration isa thermal treatment method in which organic compounds are oxidized at elevatedtemperatures (combusted) and decomposed intobasicproducts ofcombustionsuch as carbondioxide (COz), water vapor, and (in some cases) inorganic gases. In most incineratorapplications, an auxiliary heat source such as fossil fuel-fired burners is used to achieve thetemperature necessary to evaporate water from the feed material and combust the organiccompounds. Emissions from the incineratorwill be controlled with proper emission controldevices such as a baghouse, and by routing off-gases through an afterburner for completecombustion ofgases prior to release to the atmosphere. Results from atrial bum will be usedto define operating parameters for the incinerator. During a trial bum, the incinerator willbe operated for a specified regulatory duration under assumed operating conditions tomonitor performance, emissions, and operational safety.

Capital costs for incineration include mobiliz.ation and project planning; site preparation;erectionofatemporary shelterfor stockpiledsoil; conductofatrialbum; and demobilizationand site restoration. Operating costs include excavationofsoils from the CAMU; incineratoroperation; labor; utilities; confirmation sampling; and disposal of treated soil in the SoilRepository. Corps of Engineers program management costs are additional. For costestimating purposes, the treatment unit is assumed to be located adjacent to the CAMU anddisposal is assumed to be in the Soil Repository. Treatment capacity is assumed to beapproximately 250 tons/day based oncommercially available equipment, experience atothersites, and consideration ofthe clay soil at IAAAP. Costs for treatment of9,000 cubic yardsof explosives-contaminated soil are estimated as follows:

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1),\H..11P1t0lECTS-115144__.,.lItllll'ae44la_.wpd 23 August 14, 1998

TABLE 3Costs

Alternative EIA: Incineration

Unit Rate Cost

Capital Cost $ 4,600,000

Operating Cost $ 370/cy $ 3,330,000

Subtotal $ 7,930,000

Project Contingency 30% $ 2,380,000

Total Project Budget $10,310,000

This represents a present worth value of $10,3 10,000. Details of these cost estimates arepresented in the Feasibility Study report.

Remediation could be completed in less than two months of incineration. Additional timewould be required for planning, design, mobilization, conducting a trial bum and obtainingapprovals, and for demobilization. These activities are expected to require approximatelytwo additional years.

Significantapplicable or relevant and appropriate requirements (ARARs) for this alternativeinclude requirements relating to ambient air quality and air emissions specified under lAC28.1 (455 B), lAC 22.3 (3), lAC 23.3 (2) (a) and Table 1, and lAC 23.3 (a) (c) (1);CERCLA's preference for treatment specified under Section 121 (b); Land DisposalRestrictions specified under 40 CFR 268 Subparts A and D; and requirements forincineration of hazardous waste specified under 40 CFR 264, Subpart O.

Alternative E1 B: Low Temperature Thermal Desorption (LTID)

This alternative consists ofon-site LTTD, with disposal of residuals in an on-site landfill;it is assumed that additional treatment (Le., solidification/stabilization for metals) will notbe required. The principal elements of this alternative are as follows:

e Excavate explosives-contaminated soil from the CAMU and transport it to atemporary treatment facility on-site.

e Screen, shred and blend the soil to produce a uniform feed material.

e Process the blended soil through a mobile direct-fired LTTD unit to achieve disposalcriteria outlined below.

Iowa Anny Ammunition PlantSoils OU#1. Record of Decision (Revision No.1)\\H..1IPROIECTSoIISN·__41IIR_41llecl02.wpcl 24 August 14, 1998

• Following confirmation sampling, dispose of treated soil on-site either:

a. For soils with cumulative risk less than 1O~, in compliance with LDRs, andexceeding Summers model remediation goals, dispose in the Soil Repositoryor under another synthetic landfill cap on-site.

b. For soils with cumulative risk less than 1O~, in compliance with LDRs, and. satisfying Summers model remediation goals, dispose on IAAAP property in

an appropriate manner protective of human health and the environment.

LTID is the primary treatment technology used under this alternative. LTID treatment issimilar to rotary kiln incineration except that the process operates at a lower temperature(typically 200 to 600 Of in the primary chamber, depending on the contaminants ofconcern).At this lower temperature, volatilization is the primary mechanism at work in the primarychamber. Organic contaminants are driven off as gases which are then destroyed at highertemperatures in the secondary chamber or afterburner. Emissions from theLTID unit willbe controlled with proper emission control devices such as a baghouse, and by routing off­gases through an afterburner for complete combustion of gases prior to release to theatmosphere. Results from treatability tests will be used to defme operating parameters forthe LTTD unit.

Capital costs forLTID treatmentincludemobilizationand projectplanning, sitepreparation,erection of a temporary shelter for stockpiled soil, conduct of treatability tests, and .demobilization and site restoration. Operating costs include excavation of soils from theCAMU, LTID operation, labor, utilities, confirmationsampling, and disposal oftreated soilin the Soil Repository. Corps ofEngineers program management costs are additional. Forcost estimating purposes, the treatment unit is assumed to be located adjacent to the CAMUand disposal is assumed to be in the Soil Repository. Treatment capacity is assumed to beapproximately 5 tonslhour based on commercially available equipment, experience withother applications, and consideration ofthe clay soil at IAAAP. Costs for treatment of9,000cubic yards of explosives-contaminated soil are estimated as follows:

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\Hos-1IPROJECTS-115144_ar6l«jaVlOO't5e44jaJ'0d02.. 25 August 14, 1998

TABLE 4Costs

Alternative EIB: L'ITD

Unit Rate Cost

Capital Cost $ 830,000

Operating Cost $ 300/cy $ 2,700,000

Subtotal $ 3,530,000

Project Contingency 30% $ 1,060,000

Total Project Budget $ 4,590,000

This represents a present worth value of $4,590,000. Details of these cost estimates arepresented in the Feasibility Study report.

It is expected that remediation could be completed in approximately six months of LTIDoperation. Additional timewould berequired for planning, design, mobilization, conductingtreatability tests and a trial bum and obtaining approvals, and for demobilization. Theseactivities are expected to require approximately two additional years. Treatability test resultswill provide a clearer indication of actual time required for LTID treatment.

Significant ARARs for this alternative include requirements relating to ambient air qualityand air emissions specified and lAC 28.1 (455 B), lAC 22.3 (3), lAC 23.3 (2) (a) and Table1, and lAC 23 .3 (a) (c) (1); CERCLA's preference for treatment specified under Section 121(b); Land Disposal Restrictions specified under 40 CFR 268 Subparts A and D; andrequirements for incineration at hazardous waste specified under 40 CFR 264, Subpart O.

Alternative E2A: Composting

In this alternative, composting will be used to treat contaminated soils. The principalelements of this alternative are as follows:

• Excavate explosives-contaminated soil from the CAMU and transport it to atemporary treatment facility on-site.

• Screen, shred and blend the soil to produce a uniform feed material.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\H_IIPROIECfS.IIlM4.-.VlOO-.,._..... 26 August 14,1998

• Process the blendedsoil in a temporary compost shelterby mixing with amendmentssuch as manure, com stalks, and food processing wastes; spreading the mixture inwindrows; and turning periodically to help aerate the material and regulatetemperature. Soils will be treated to achieve disposal criteria outlined below.

• Following confIrmation sampling, dispose of treated soil on-site either:

a. For soils with cumulative risk less than 10-6, in compliance with LDRs, andexceeding Summers model remediation goals, dispose in the Soil Repositoryor under another synthetic landfIll cap on-site.

b. For soils with cumulative risk less than 10-6, in compliance with LDRs, and.satisfying Summers model remediation goals, dispose on IAAAP property inan appropriate manner protective of human health and the environment.Treatment residuals must also be shown to be non-toxic or not bioavailableat levels posing a threat to human health or the environment.

Composting is the primary treatment technology used under this alternative. Compostingis a biological process in which naturally occurring micro-organisms degrade contaminantsinto intern)ediates, some ofwhich bind to soil organic components in such away as to reducethe mobile or extractable fraction of the contaminants. In windrow composting,contaminated soils are mixed with locally available amendments (manure, wood chips, foodprocessing wastes, molasses, etc.) and water, then spread out in long rows. Facilitiesrequired for window composting include an asphalt pad and a temporary structure to protectthe windrows from precipitation and temperature fluctuations. Conventional earth movingequipment (front end loader, dump trucks) is used to place contaminated soil and removefInished compost, while a commercially available windrow turning machine is used in thecomposting process. Alternatives to windrow composting include use of a mechanicalagitated vessel to help aerate the material and regulate temperature, while in a static pile thesoiVamendment mix is left undisturbed.

It is assumed that treated soils will be disposed of in an on-site landfIll (disposal option "a"above). If composting can reliably achieve risk levels less than 10-6 and comply withSummers' model treatment requirements and LDRs, on-site land application ofthe fInishedcompost (disposal option "b" above) may be feasible. However, additional studies of long­term stability and toxicity of compost treatment residues will be required to verify theacceptability of unrestricted land application. Because of available landfIll capacity, theArmy does not expect land application to provide signifIcant cost advantages.

Iowa Army Ammunition PlantSoils QU#1, Record of Decision (Revision No.1)\\H...'IPROJECTS-'I5I«_~VlClll'i4l44ja.r0d02.wpd 27 August 14, 1998

Capital costs for composting include mobilization and project planning; site preparation;construction ofa compost shelter; and demobilization and site restoration. Operating costsinclude excavation of soils from the CAMU; compost facility operation; labor; compostamendments; utilities; confirmation sampling; and disposal of treated soil in the SoilRepository. For cost estimating purposes, the treatment unit is assumed to be locatedadjacent to the CAMU and disposal is assumed to be in the Soil Repository. Corps ofEngineers program management costs are additional. A treatment cycle ofapproximately30 days per batch is assumed as a year-round average, allowing 5 days for loading, 20 daysfor composting, and 5 days for unloading. Costs for treatment of 9,000 cubic yards ofexplosives-contaminated soil are estimated as follows:

TABLESCosts

Alternative E2A: Composting

Unit Rate CostCapital Cost $ 1,050,000

Operating Cost $260 - $360/cy $ 2,340,000 - $ 3,240,000Subtotal $ 3,390,000 - $ 4,290,000

Project Contingency 30% $ 1,020,000 - $ 1,290,000Total $ 4,410,000 - $ 5,580,000

This represents a present worth value of $ 4,410,000 - $ 5,580,000. The variation inestimatedoperatingcosts indicates thepotential rangeofamendment requirements and costs.Details of these cost estimates are presented in the Feasibility Study report.

It is expected that remediation could be completed in approximately one year of compostfacility operation. Additional time would be required for planning, design, mobilization,process optimization testing, and demobilization.

SignificantARARs forthis alternative include CERCLA's preferencefor treatment specifiedunder Section 121 (b); Land Disposal Restrictions specified under 40 CFR 268 Subparts Aand D; and requirements for composting ofhazardous waste in buildings specified under 40CFR Part 264, Subpart DD.

Alternative E2B: Bio-5lurry Treatment

In this alternative, either aerobic/anoxic or anaerobic bio-slurry treatment will be used totreat contaminated soils. The principal elements of this alternative are as follows:

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\Vl...'IPROJ!CT$-II5N4_oNI44ja\R~.IOdII2.""", 28 August 14, 1998

• Excavate explosives-contaminated soil from the CAMU and transport it to atemporary treatment facility on-site.

• Screen, shred and blend the soil to produce a uniform feed material.

• Process the blended soil in a bio-slurry treatment facility. Soil will be treated toachieve disposed criteria outlined below.

• Following confmnation sampling, dispose oftreated soil on-site either:

a. For soils with cumulative risk less than 1O~, in compliance with LDRs, andexceeding Summers model remediation goals, dispose in the Soil Repositoryor under another synthetic landfill cap on-site.

b. For soils with cumulative risk less than 1O~, in compliance with LDRs, andsatisfying Summers model remediationgoals, disposeon IAAAP property inan appropriate manner protective of human health and the environment.Treatment residuals must also be shown to be non-toxic or not bioavailableat levels posing a threat to human health or the environment.

If disposal option "a" is selected, an additional treatment process will berequired for treatment ofslurry water following solids dewatering and priorto disposal.

Bio-slurry treatment is the primary treatment technology used under this alternative. Bio­slurry treatment uses naturally occurring micro-organisms to degrade contaminants. Theprocess involves blending contaminated soils with water to produce a slurry ofbetween 15and 40 % solids, adding nutrients and co-substrates (such as molasses), and mixing.Processes may use either aerobic/anoxic regimes and anaerobic regimes. In aerobic/anoxicprocesses, blowers cycle on and off to alternate between aerobic (oxygenated) and anoxic(oxygen-starved) conditions, while mechanical mixers maintain solids in suspension. Inanaerobic processes, no aeration is provided and anaerobic conditions are maintained~

mechanical mixers again maintain solids in suspension.

It is assumed that thickening and dewatering will be required prior to disposal in an on-sitelandfill (disposal option "a" above). Ifbio-slurry treatment can reliably achieve risk levelsless than 1O~ and comply with Summers' model treatment requirements and LDRs, on-siteland application ofthe liquid slurry (disposal option"b" above) may be feasible. However,additional studies of long-term stability and toxicity oftreatment residues will be requiredto verify the acceptability of unrestricted land application. Because of available landfillcapacity, the Anny does not expect land application to provide significant cost advantages.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\H...11PR0lECTS·II5N._oII5I«IaVl~• .nMI02.wpd 29 August 14, 1998

Capital costs for bio-slurry treatment include mobilization and project planning; sitepreparation; construction of a treatment facility including three 250,000 gallon treatmenttanks, solids dewatering facilities (assumed to be precoat rotary drum vacuum filters), anequipment building, and associated equipment; and demobilization and site restoration.Operating costs include excavation of soils from the CAMU; treatment facility operation;labor; chemicals; utilities; confmnation sampling; and disposal of treated soil in the SoilRepository. Corps of Engineers program management costs are additional. For costestimating purposes, the treatment unit is assumed to be located adjacent to the CAMU anddisposal is assumed to be in the Soil Repository. A treatment cycle of approximately 10weeks per batch is assumed as a year-round average. With two tanks processing at all times,this allows an additionaloneweek for loading and three weeks forunloading and dewatering.Land applicationofthetreated liquid slurrywould require a longer treatment cycle (assumedto be approximately 18 weeks). Costs for treatment of 9,000 cubic yards of explosives­contaminated soil are estimated as follows:

TABLE 6Costs

Alternative E2B: Bio-Slurry Treatment

Unit Rate Cost

Capital Cost $ 1,950,000

Operating Cost $300 - $440/cy $ 2,700,000 - $ 3,960,000

Subtotal $ 4,650,000 - $ 5,910,000

Project Contingency 30% $ 1,400,000 - $ 1,770,000

Total $ 6,050,000 - $ 7,680,000

This represents a present worth value of $5,740,000 to $7,070,000 based on a 5% annualdiscount rate. The variation in estimated operating costs indicates the potential range ofslurry concentrations in the treatment tanks. Details ofthese cost estimates are presented inthe Feasibility Study report.

It is expected that remediation to concentrations suitable for landfilling could be completedin 3 to 5 years. Additional time would be required for planning, facility design andconstruction, mobilization, process optimizationtesting, and demobilization. These activitiesare expected to require approximately two additional years.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)1'It..IIPRO.IECTS-l15144__4j.VlOIMI44jo_..... 30 August 14, 1998

SignificantARARsfor this alternative includeCERCLA's preferencefor treatmentspecifiedunder Section 121 (b); Land Disposal Restrictions specified under 40 CFR 268 Subparts Aand D; and surface water quality criteria and limitations on discharges to surface watersspecified under lAC 61.3 (455B) and 33 USC Section 402.

2.7.2 Alternatives for Explosives plus Metals Contaminated Soils

Approximately 600 cubic yards of soil are identified as being contaminated with bothexplosives and metals, out ofan estimated total of 10,000 cubic yards ofcontaminated soil.Alternatives for treating soil contaminatedwith both explosives and metals in excess ofLDRcriteria are presented in the following paragraphs. The volume of soil contaminated withboth explosives and metals is small enough that it is not expected to affect the overall timerequired for soils remediation under any of these alternatives.

Alternative M1: Explosives Treatment Followed by Solidification

In this alternative, soils contaminated with both explosives and metals exceeding LDRcriteriawill be managed separately from soils contaminated solely with explosives, using thesame technology selected for management of explosives-contaminated soil, followed bysolidification/stabilization treatment for metals. Residuals will be disposed in an on-sitelandfill. It is assumed that costs for treatment ofthe explosives portion ofthe contaminationin these soils will be determined by the technology selected for management ofexplosives­contaminated soils. Capital costs are assumed to be covered under alternatives EIA, EIB,E2A, and E2B, and operating costs for treatment of the explosives' portion of thecontamination vary from $260 to $440 per cubic yard. Operating costs forsolidification/stabilization of metals are estimated at approximately $150 per cubic yard.Therefore, the total incremental cost for treatment of600 cubic yards of contaminated soilis estimated at between $250,000 and $350,000.

ARAR's requirements will be determined by the alternative selected for treatment of theexplosives - contaminated soil.

Alternative M2: Solidification/Stabilization With Activated Carbon

This alternative consists of stabilization using activated carbon along with solidificationmaterials such as cement and flyash, with disposal of residuals in an on-site landfill.

A temporary solidification/stabilization facility will be erected on-site (assumed to beadjacent to the CAMU or the fmal disposal site). Soil stockpiled in the CAMU will beexcavated, transported to the solidification/stabilization facility, screened, shredded andblended to produce a uniform feed material; and processed through thesolidification/stabilization facility. Following confirmation sampling, treated soil will be

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transported to the disposal site (assumed to be the Soil Repository) where it will be spread,compacted, and covered.

•Since solidification/stabilization immobilizes contaminants rather than destroying them,compliance with remedial action objectives will be determined based on analysis ofleachateas a measure of groundwater protectiveness. For metals and explosives with ToxicityCharacteristic Leaching Procedure (TCLP) limits established under RCRA, treatment willbe considered protective of human health and the environment ifTCLP results are belowRCRA regulatory limits. For other COCs, TCLP remediation goals for groundwaterprotection are established based on the following hierarchy:

1. 100 times EPA Drinking Water Maximum Contaminant Level.

2. 100 times EPA Lifetime Health Advisory.

3. Forcarcinogens, 100times thegroundwaterconcentration correspondingtoEPA 10'"risk levels based on residential water usage.

4. For non-carcinogens, 100 times the groundwater concentration corresponding to aHazard Index of 1.0 based on residential water usage.

It is assumed that this material will be processed at the same time as other materials in theCAMU. Capital costs for planning, site preparation, mobilization and demobilization are,therefore, assumed to be covered under alternatives EIA, EIB, E2A, and E2B. Operatingcosts for solidification/stabilizationusing activated carbon are estimated at $220 to $380 percubic yard, depending upon the amount of activated carbon, cement, and flyash required.Therefore, the total incremental cost for treatment of 600 cubic yards ofcontaminated soilis estimated at between $130,000 and $230,000.

SignificantARARs for this alternative include CERCLA's preferencefor treatmentspecifiedunder Section 121 (b), and Land Disposal restrictions specified under 40 CFR 268 SubpartsAandD.

Alternative M3: Off-Site Disposal

Under this alternative, soil contaminated with both explosives and metals would beexcavated from the CAMU and transported to a commercial waste treatment and disposalfacility off-site. Capital costs for planning, sitepreparation, mobilizationand demobilizationare assumed to be covered under alternatives ElA, ElB, E2A, and E2B. Operating costs areestimated at $600,000 to $1,000,000 depending on unit prices charged by commercial waste

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disposal operators for transportation and disposal. These costs assume disposal as ahazardous waste based on exceedingTCLP regulatory limits underRCRA. Off-site disposalfacilities must be permitted under RCRA and operate in compliance with permit conditions,based on CERCLA Off-site Policy (NCP 300.440).

2.7.3 Alternatives For SVQC-Contaminated Soils

Approximately 200 cubic yards of soil are identified as being contaminated with SVOCs.Alternatives for treating these soils are the same as presented above for soil contaminatedsolely with explosives:

Alternative S1A: Incineration

This alternative consists ofon-site incineration, with disposal ofincinerator ash in an on-sitelandfill. Capital costs for incineration are assumed to be covered under alternative EIA forexplosives-contaminated soils. Operating costs are estimated at $370 per cubic yard.Therefore, the incremental cost for treatment ofapproximately 200 cubic yards of SVOC­contaminated soil is estimated at approximately $74,000. Incineration of SVOC­contaminated soils is expected to add only a couple ofdays to the remediation time. ARARsrequirements are,equivalent to those for treatment of explosives contaminated soils underAlternative EIA.

Alternative S1 B: Low Temperature Thermal Desorption (LTTD)

This alternative consists of on-site low temperature thermal desorption (LTTD), withdisposal ofresiduals in an on-site landfill. Capital costs for LTTD treatment are assumedto be covered under alternative EIB for explosives-contaminated soils. Operating costs areestimated at $300 per cubic yard. Therefore, the incremental cost for treatment ofapproximately 200 cubic yards of SVOC-contaminated soil is estimated at approximately$60,000. LTTD treatment ofSVOC-contaminated soils would add less than a week to theremediation time. ARARs requirements are equivalentto those for treatment ofexplosives ­contaminated soils under Alternative EIB.

Alternative S2A: Composting

This alternative consists of on-site composting, with disposal of residuals in an on-sitelandfill. Capital costs for compost treatment are assumed to be covered under alternativeE2A for explosives-contaminated soils. Operating costs are estimated at $260 to $360 percubic yard. Therefore, the incremental cost for treatment ofapproximately 200 cubic yardsofSVOC-contaminated soil is estimated at approximately $52,000 to $72,000. Compostingof SVOC-contaminated soils would add roughly two weeks to the overall remediationrequirement. ARARs requirements are equivalent to those for treatment of explosives-

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contaminated soils under Alternative E2A.

Alternative S2B: Bio-slurry Trea~ent

This alternative consists ofon-site bio-slurry treatment, with disposal ofresiduals in an on­site landfill. Capital costs for bio-slurry treatment are assumed to be covered underalternative E2B for explosives-contaminated soils. Operating costs are estimated at $300 to$440 per cubic yard. Therefore, the incremental cost for treatment of approximately 200

. cubic yards of SVOC-contaminated soil is estimated at approximately $60,000 to $88,000.Bio-slurry treatment of SVOC-contaminated soils would add roughly one batch to theoverall remediation requirement. This is not expected to have a significant impact on theoverall remediation schedule. ARARs requirements are equivalent to those for treatment ofexplosives-contaminated soils under Alternative E2B.

Alternative S3: Off-Site Disposal

Underthis alternative, soil contaminatedwith SVOCswill be excavated from the CAMU andtransported to a commercial waste treatment and disposal facility off-site. Since samplingdata does not exceed hazardous waste criteria, it is assumed that these soils can be disposedofas non-hazardous waste. Capital costs are assumed to be covered under alternatives EIA,EIB, E2A, and E2B. Operating costs are estimated at $30,000 to $70,000 depending on unitprices charged by commercial waste disposal operators for transportation and disposal. Off­site disposal facilities mustbe permittedunderRCRA and operate in compliancewith permitconditions, based on CERCLA Off-site Policy (NCP 300.440).

2.8 Summary of the Comparative Analysis of Alternatives

USEPA has established nine criteria that balance health, technical, and cost considerations todetermine the most appropriate remedial action alternative. These criteria are used to select aremedial action that is protective of human health, and the environment, attains ARARs, is costeffective, and utilizes permanent solutions and treatment technologies to the maximum extentpracticable. In accordance with Superfund guidance, each alternative is assessed against thefollowing evaluation criteria:

• Overall Protection ofHuman Health and the Environment: Describes how the alternative,as a whole, achieves and maintains protection ofhuman health and the environment.

• Compliance with Applicable or Relevant and Appropriate Requirements (ARARs):Describes how the alternative complies with ARARs or, if a waiver is required, how it isjustified; also addresses other information from advisories, criteria, and guidance "to beconsidered".

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• LQng-Tenn Effectiveness and Pennanence: Evaluates the IQng-term effectiveness Qfalternatives in maintaining protectiQn Qfhuman health and the environment after respQnseQbjectives have been met.

• ReductiQn QfTQxicity. MQbility. and VQlumeThrough Treatment: Evaluates the anticipatedperfQrmance Qfthe specific treatment technQIQgies an alternative may emplQY.

• ShQrt-Tenn Effectiveness: Examines the effectiveness Qfalternatives in protecting humanhealth and the environment during the constructiQn and implementatiQn Qf a remedy untilrespQnse Qbjectives have been met.

• Implementability: Evaluates the technical and administrative feasibility Qfalternatives andthe availability Qf required gQQds and services.

• CQst: Evaluates the capital and QperatiQn and maintenance (O&M) costs Qfeach alternative.

• State Acceptance: Reflects the state's apparent preferences amQng Qr concerns abQut thealternatives.

• CQmmunityAcceptance: Reflects the community's apparentpreferences amQngQrconcernsabQut alternatives.

The analysis Qfalternatives is arranged by type Qfcontaminant: explQsives, explQsives plus metals,SVOCs.

2.8.1 Evaluation of Alternatives For Explosives - Contaminated Soils

Overall PrQtectiQn QfHuman Health and the Environment: Since bQth Thennal Treatment(incineratiQn and LITD) and BiQIQgical Treatment (compQsting and biQ-slurry treatment)prQvide fQr destructiQn/degradatiQn Qf contaminants tQ acceptable risk levels and themanagement Qf residuals (either thrQugh landfilling Qr treatment to IQwer levels protectiveQfgrQundwater), bQth categQries Qfalternatives are considered equally prQtective Qfhuinanhealth and the environment.

Compliance with ARARs: MQst ARARs issues will be comparable fQr bQth ThermalTreatment and BiQIQgical Treatment, althQugh Thermal Treatment will invQlve mQreconcerns related tQ air emissiQns (i.e., ambient air quality standards, visible emissiQnstandards, emissiQnstandards fQrparticulate matter) and compliancewithEPA's requirementfQr a combustiQn facility risk assessment. Significant ARARs are identified in Tables ISa,ISb, and ISc.

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Long-Term Effectiveness and Permanence: Thermal Treatment will permanently destroyexplosives contaminants that are present above remediation goals (RGs), while BiologicalTreatment will degrade and stabilize them. Both of these processes are consideredirreversible. While composting has been conducted on a scale similar to that required atIAAAP, long-term effectiveness of Biological Treatment is difficult to assess because ofuncertainties about the degree of treatment that can be achieved and the bio-availability oftreatment residuals. Thermal Treatmentmay be considered more effective since destructionofcontaminants is more complete. However, long-term landfill operation and maintenanceis required under either alternative unless Biological Treatment is determined to beacceptable for unrestricted land application.

ReductionofToxicity. Mobility. and VolumeThroughTreatment: BothThermal Treatmentand Biological Treatment will reduce contaminant levels to below RGs, although ThermalTreatment will provide a greater degree of reduction in contaminant toxicity and mobility.Incineration will result in somevolume reduction, while composting will result in a volumeincrease. LTID and bio-slurry treatment are not expected to change soil volumessignificantly as a result of treatment.

Short-Term Effectiveness: While explosives hazard assessments and control measures willbe required under both Thermal and Biological Treatment, the requirements for ThermalTreatment are expected to be more rigorous than for Biological Treatment. A combustionrisk assessment will demonstrate that risks associated with Thermal Treatment can bemanaged effectively. Other short-term effectiveness issues are considered to be equivalent.

Implementability: Both Thermal Treatment and Biological Treatment involve a number ofimplementability issues. Both use commercially available equipment. Testing will berequired for each alternative prior to implementation: incineration and LTID will requirea trial bum; LTTD has not been utilized for remediation of explosives-contaminated soilsin this country and testing will, therefore, be required to demonstrate its effectiveness;although testing has been done to demonstrate the effectiveness ofcomposting and bioslurrytreatment, additional testing will be required to define process and operating parameters.Once approvals are received and equipment is mobilized, Thermal Treatment can beaccomplished in a few months while Biological Treatment will require several years.

Cost: The costs of Thermal and Biological Treatment may be compared as follows:

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TABLE 7Alternative Cost Comparisons

Explosives

Alternative Capital Cost Operating Cost Present Worth(incl. contingency)

E1A: Incineration $ 4,600,000 $ 3,330,000 $10,310,000

E1B: LTID $ 830,000 $ 2,700,000 $ 4,590,000

E2A:Composting $ 1,050,000 $ 3,390,000- $ 4,290,000 $ 4,410,000- $,580,000

E2B: Bio-slurry $ 1,950,000 $ 2,700,000- $ 3,960,000 $ 5,740,000- $7,070,000

Corps ofEngineers program management costs are not included in the above costs.

Operating costs of each alternative may be influenced significantly by variables that aredifficult to predict at this time. Operating efficiencies (including cycle times, labor costs,energy costs, and amendment mixes and costs) may vary considerably for any of theseprocesses, depending on the physical characteristics of the soil, weather, treatability of thecontaminants, and individual contractor capabilities. Previous studies at IAAAP includedan evaluation of Thermal and Biological Treatment alternatives considering the impact ofvarying volumes of contaminated soil. Although total costs were significantly influencedby soil volumes, the relative positioning of the alternatives were not affected. If furtherinvestigations demonstrate that LTID can achieve PRGs, it appears to be the least costlyalternative. However, with favorable amendment requirements and costs, composting andbio-slurry treatment may be competitive with LTID. Incineration is considerably morecostly.

State and Community Acceptance: State and community acceptance issues are summarizedin Section 3 of this ROD.

Summary: In summary, Biological Treatment (Le., composting) may be cost competitivewith Thermal Treatment (Le., LTID) or may cost up to a million dollars (roughly 20%)more. In other criteria one alternative or the other may offer specific advantages, but bothcomply with RAOs and on balance are considered equivalent.

2.8.2 Evaluation of Alternatives for Explosives Plus MetalsContaminated Soils

Overall Protection ofHuman Health and the Environment: Since Alternative M1 (Explosives

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Treatment Followed by Stabilization), Alternative M2 (Solidification/Stabilization WithActivated Carbon), and Alternative M3 (Off-site Disposal) all provide fordestruction/degradation, immobilization, and/or containment of contaminants, all threealternatives are considered equally protective ofhuman health and the environment.

Compliance with ARARs: Thermal Treatment under Alternative M 1 would involve moreconcerns related to air emissions and compliance with EPA's requirement for a combustionfacility risk assessment. ARARs are not a part of off-site alternatives. Off-site alternativesmust meet conditions specified in the off-site facility's permit. Significant ARARs areidentified in Tables ISa, ISb, and ISc. .

Long-Term Effectiveness and Permanence: The long-term effectiveness of Alternative Mlwill depend on the process selected for explosives treatment as discussed above for Explosives­Contaminated Soils. Both Alternatives M2 and M3 stabilize contaminants rather thandegrading them, and both require long-term landfill operation and maintenance to ensurecontinued effectiveness.

Reduction of Toxicity. Mobility. and Volume Through Treatment: Alternative Ml wouldprovidereduction inbothcontaminanttoxicity and mobility through destruction ordegradationof explosives and solidification/stabilization of metals. Alternatives M2 and M3 wouldprovide reduction in contaminant mobility only. Contaminant volume is not expected to bereduced significantly under any of the alternatives.

Short-Term Effectiveness: Short-term effectiveness would be comparable for all threealternatives, although Thermal Treatment underAlternative Ml would involve more rigorousexplosives, hazard assessments, and control measures.

Implementability: Off-Site Disposal (Alternative M3) would be the easiest alternative toimplement. Process development testing would be required for Explosives TreatmentFollowed by Stabilization (AlternativeM1)and for Solidification/StabilizationWithActivatedCarbon (Alternative M2). In addition, th~ presence of metals may interfere with theimplementability ofBiological Treatment under Alternative MI.

Costs: Costs may be compared as follows:

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TABLESAlternative Cost Comparisons

Explosives Plus Metals

Alternative Incremental Cost

M 1: Explosives Treatment Followed by Stabilization $250,000 to $350,000

M2: Solidification/Stabilization With Activated Carbon $130,000 to $230,000

M3: Off-Site Disposal $600,000 to $1,000,000

State and Community Acceptance: State and community acceptance issues are summarized inSection 3 of this ROD.

2.8.3 Evaluation of Alternatives for SVOC-Contaminated Soils

Overall Protection ofHuman Health and the Environment: The overall protection providedby Biological Treatment is difficult to assess because ofuncertainties about its effectivenessfor the specific SVOCs ofconcern. The remaining alternatives (Thermal Treatment and Off­site Disposal) are considered equally protective ofhuman health and the environment.

Compliance with ARARs: Thermal Treatment would involve more concerns related to airemissions and compliance with EPA's requirement for a combustion facility risk assessment.ARARs are not a part of off-site alternatives. Off-site alternatives must meet conditionsspecified in the off-site facilities' permit. SignificantARARs are identified in Tables 15a, 15b,and 15c.

Long-Term Effectiveness and Permanence: Thennal Treatment will permanently destroycontaminants that are present above RGs. The effectiveness of Biological Treatment isdifficult to assess because ofuncertainties about ability to treat the specific SVOCs ofconcern.Off-Site Disposal contains contaminants rather than degrading them, and requires long-tennlandfill operation and maintenance to ensure continued effectiveness.

Reduction of Toxicity. Mobility. and Volume Through Treatment: Thermal Treatmentprovides reduction in both contaminant toxicity and mobility through destruction ofcontaminants. The reduction provided by Biological Treatment is difficult to assess becauseof uncertainties about ability to treat the specific SVOCs of concern. Off-Site Disposalprovides reduction in contaminant mobility only. Incineration will result in some volumereduction, while cornpostingwill result in avolume increase. LTID, bio-slurry treatment, andoff-site disposal are not expected to change soil volumes significantly.

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Short-Term Effectiveness: Short-term effectiveness will be comparable for all threealternatives, although Thermal Treatment will involve more rigorous explosives, hazardassessments, and control measures.

Implementability: Off-Site Disposal will be the easiest alternative to implement. Processdevelopment testing will be required for Biological Treatment, and trial bums will be requiredfor Thermal Treatment.

Costs: Costs may be compared as follows:

TABLE 9Alternative Cost Comparisons

SVOCs

Alternative Incremental Cost

SIA: Incineration $74,000

SIB: LTID $60,000

S2A: Composting $52,000 to $72,000

S2B: Bio-slurry $50,000 to $72,000

S3: Off-Site Disposal $30,000 to $70,000

State and Community Acceptance: State and community acceptance issues are summarizedin Section 3 ofthis ROD.

2.8.4 Environmental Consequences (NEPA Evaluation)

The feasibility study reviewed the environmental and socioeconomic effects of remediatingcontamination at the IAAAP, in compliance with the National Environmental Policy Act of1969 (NEPA). Thermal treatment, biological treatment and "No Action" alternatives werereviewed for effects on numerous aspects ofhydrology, soils, ecology, socioeconomics, andpublic health. No significant adverse effects were identified in the review. Further, none wereidentified by reviewing agencies or the general public during the public commentperiod oftheProposed Plan. It was the fmding of the NEPA review that neither biological nor thermaltreatment would adversely affect environmental resources at the lAAAP. A combustionfacility risk assessment will be performed prior to implementation of the remedial action toaddress potential minor risks ofadverse effects ofair pollution and construction worker safetyfrom thermal treatment technologies.

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2.9 Selected Remedy

Based on an evaluation of the various alternatives, the Army and EPA conclude that BiologicalTreatment (Alternatives E2A and E2B) and LTTD Thermal Treatment (Alternative EIB) are capableof providing treatment to reduce the toxicity, mobility, and volume ofprincipal threat contaminantsin the CAMU in response to CERCLA's expressed preference for treatment, complying with landdisposal restrictions (LDRs) for disposal oftreated soil, and providing long-term protection ofhumanhealth and the environment.

LTTD Thermal Treatment is the remedy selected for explosives-contaminated soils, with BiologicalTreatment as the contingency remedy pending results of the LTID Thermal Treatment feasibilitytesting field demonstrations, and risk assessment. The feasibility testing and field demonstrations willinclude additional process development and economic evaluations to further define the performanceand cost OF the LTTD Thermal Treatment alternative. In addition, a combustion facility riskassessment will be conducted consistent with EPA policies and guidance prior to implementation ofLTTD Thermal Treatment. The results of this risk assessment will be presented to the public with anopportunity to comment prior to commencing the site work. If the feasibility testing, fielddemonstrations, or risk assessment shows that LTID Thermal Treatment cannot be conducted in aprotective manner, appropriate documentation will be prepared for review and submitted to theAdministrative Record, and the contingency remedy will be implemented. Implementation ofspecificbiological treatment processes (composting, bio-slurry, or other) will be determined based ondemonstrated effectiveness following treatability testing using IAAAP soils, and on solicitation ofcompetitive cost proposals from remediation technology vendors.

Solidification/Stabilization With Activated Carbon (Alternative M2) is the remedy selected for soilscontaminated with explosives plus metals exceeding LDRs, and Off-Site Disposal (Alternative S#)is the remedy selected for soils contaminated with SVOCs. These alternatives comply with remedialaction objectives at a lower cost than other alternatives and are equivalent to or better than otheralternatives in most of the remaining criteria.

2.9.1 Description

The major components of the selected remedy include:

Explosives-Contaminated Soils

• Excavated explosives-contaminated soils from the CAMU and transport it to a temporarytreatment facility on-site.

• Screen, Shred and blend the soil to produce a uniform feed material.

• Process the blended soils through a mobile direct-fired low-temperature thermal desorptionunit (LTTD) (Selected Remedy) or a temporary Biological Treatment Unit (ContingentRemedy).

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41. August 14, 1998

• Following confirmation sampling, dispose of treated soil according to the followingcriteria:

a. For soils with cumulative risks less than 10-6, in compliancewith LDRs, and exceedingSummers model remediation goals, dispose in the Soil Repository or under anothersynthetic landfill cap on-site.

a. Forsoils with cumulative risks less than 10-6, in compliancewith LDRs, and satisfyingSummers model remediation goals, dispose on IAAAP property in an appropriatemanner protective of human health and the environment. For Biotreated soils,treatment residuals must also be shown to be non-toxic or not bioavailable at levelsposing a threat to human health or the environment.

Costs for treatment of 9,000 cubic yards of explosives-contaminated soil are estimated asfollows:

TABLE 10Selected Remedy Costs

Explosives-Contaminated Soils

LTTD Treatment Composting Bio-Slurry Treatment

Unit Cost Unit Rate Cost Unit Rate CostRate

Capital Cost $830,000 $1,050,000 $ 1,950,000

$260 $2,340,000 $300 $ 2,700,000Operating Cost $300/cy $2,700,000 to to to to

$360/cy $3,240,000 $440/cy $ 3,960,000

$1,020,000 $ 1,400,000Project Contingency 30% $1,060,000 30% to 30% to

$1,290,000 $ 1,770,000

Total $4,590,000 $4,410,000 to 5,580,000 $ 6,050,00 to 7,6

Estimated TIme Requiredfor Treatment Facility Six Months One Year 'Three to Five Years

Operation

Present WorthBased on 5% $4,590,000 $4,410,000 to 5,580,000 $5,740,000 to $7,070,000

Annual Discount Rate

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Explosives Plus Metals Contaminated Soils

• Excavate explosives plus metals contaminated soil from the CAMU and transport it to atemporary treatment facility on-site.

• Screen, shred and blend the soil to produce a uniform feed material.

• Process the blended soil through a temporary solidification/stabilization facility.

• Following confirmation sampling, dispose oftreated soil on-site in the Soil Repository orunder another synthetic landfill cap.

Costs for treatment of 600 cubic yards of explosives plus metals contaminated soils areestimated as follows:

TABLE 11Selected Remedy Costs

Explosives plus Metals Contaminated Soils

Cost

Capital Cost Covered under management ofExplosives-Contaminated Soils

Operating Cost (unit rate) $220 to $380 per cubic yard

Incremental Cost (total) $130,000 to $230,000

SVOC-Contaminated Soils

• Excavate SVOC-contaminated soil from the CAMU.

• Transport the soil to a commercial waste ·treatment and disposal facility off-site.

Costs for treatment of200 cubic yards ofSVOC-contaminated soils are estimated as follows:

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TABLE 12Selected Remedy Costs

SVOC-Contaminated Soils

Cost

Capital Cost Covered under management ofExplosives-Contaminated Soil

Operating Cost (unit $150 to $350 per cubic yardrate)

Incremental Cost (total) $30,000 to $70,000

Capital costs for the selected remedy may vary as a result of changes made to the remedyduring the remedial design and construction processes. Operating costs may be influencedsignificantly by variables that are difficult to predict at this time. Operating efficiencies(including cycle times, labor costs, energy costs, and amendment mixes and costs) may varyconsiderably for any ofthese processes, depending on the physical characteristics of the soil,weather, treatability of the contaminants, and individual contractor capabilities.

2.9.2 Remediation Goals

Chemical-specific remediation goals have been established for treatment of soils stockpiledin the lAAP CAMU. These treatment goals are based on risk considerations and areconsidered to be protective ofindividuals who may be exposed at the site. Remediation goalshave been established at 1 E(-6) risk level to the reasonably maximum exposed individualconsidering an industrial land use setting. Exposure assumptions have been adopted fromthose specified in EPA guidance (see OSWERDirective 9285.6-03) Remediation goals basedon these criteria are outlined in Table 13, with exceptions noted.

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TABLE 13Soil Remediation Goals

at 10"" Risk LevelBased on IngestionlDermal Contact

ChemICal PRG(J4:~

Antimony 816Arsemc 30.0Beryllium 5

1,000ChrolDlum VI 10,000Lead' 1000

143Beozo(a)allthracene 8.1Beozo(a)pyrene 0.81Benzo(b)fiuoranthene 8.1Dibenz(a,b)anthracene 0.81Total P(;8s~ 101,3,5- Trinitrobenzcne 1022,4-Dinitrotoluene (2,4-DNT) 8.72,4,6-TNT 196~

RDX 53~

HMX 51,0001. Remediation goal for lead is determined based on the

"PRG Screen Model," rather than a carcinogenic risk.2. Remediation goal for PCB is based on EPA OSWER.

Directive 9355.4-01, "Guidance on Remedial Actions forSuperfund Sites with PCB Contamination"

3. See Table 14

Remediation goals for other constituents which may be detected at the site and which are not specifiedin this table will be established using similar criteria.

In addition to risk-based soil remediation goals for protectionofhuman health, impact to groundwaterfrom residual soil contamination has been evaluated. The Summers' model was utilized to estimatethe point at which contaminant concentrations in the soils will produce groundwater contaminationat concentrations above acceptable levels. The resultant soil concentrations can then be used as aguidelines in estimating boundaries or extent ofsoil contamination and specifying soil cleanup goalsfor remediation. The Summers' model was used to determine acceptable levels for explosives COCsin soils (RDx, and 2,4,6-TNT), which are found in on-and off-sitegroundwater. The model was basedon not exceeding groundwater concentrations of2 ppb RDX and 2 ppb 2,4,6-TNT. The model wasnot used for metals as metals are relatively immobile in the clay soils found at the IAAAP. There arealso no Summers' model limits for SVOCs. The site-specific remediation goals for the majorcontributing explosives are:

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TABLE 14Soil Remediation GoalsBased on Soil Leaching

Chemical PRG (jJ.g/g)

RDX 1.3

2,4,6-TNT 47.6

These concentrations ofRDX and 2,4,6-TNT were used as remediation goals in order to satisfy theremedial action objectives for the protection of human health and the protection of groundwater.Thesevalues supersede those presented inTable 13 for RDX and TNT for unrestricted land applicationof treated soil.

Compliance with the stated objectives for this ROD may be achieved in one of two ways:

a. Treatment to a cumulative risk level of 10-6 and compliance with LDRs, followed bymanagement ofresiduals in a landfill. This would result in 95% to 99+% removal ofcontaminants, which is consistent with CERCLA's requirement for "significant"treatment, and would be protective ofgroundwater. .

b. Treatment to lower levels protective of groundwater (as defmed by the Summers'model) followed by on-site management of treatment residuals. Unrestricted landapplication ofresiduals would require a demonstration ofcontaminant destruction ora demonstration that residuals are not toxic or not bioavailable at levels that wouldpose a threat to human health and the environment. .

Sincesolidification/stabilizationimmobilizes contaminants ratherthan destroys them, compliancewithremedial a~on objectives for treatment of explosives plus metals contaminated soil will bedetermined based on analysis ofleachate as a measure ofgroundwater protectiveness. For metals andexplosives with Toxicity CharacteristicLeaching Procedure (TCLP) limits established under RCRA,treatment will be considered protective of human health and the environment if TCLP results arebelow RCRA regulatory limits. For other chemicals of concern, TCLP remediation goals forgroundwater protection are be established based on the following hierarchy:

1. 100 times EPA Drinking Water Maximum Contaminant Level.

2. 100 times EPA Lifetime Health Advisory.

3. For carcinogens, 100 times the groundwater concentration corresponding to EPA 10-6 risklevels based on residential water usage.

Iowa Army Ammunition PlantSoils OU#1, Record of Oecision (Revision No.1)\\H...1IPRO.IECTS-1~._.II5U'i.\ll0lll5U'i's0d02._ 46 August 14, 1998

4. For non-carcinogens, 100 times the groundwater concentration corresponding to a HazardIndex of 1.0 based on residential water usage.

2.10 Statutory Determinations

In accordance with the statutory requirements of Section 121 ofCERCLA, remedial actions that areselected are required to:

• Protect human health and the environment.

• Comply with applicable or relevant and appropriate requirements (ARARs).

• Be cost effective.

• Use permanent solutions and alternative treatment technologies to the maximum extentpracticable.

• Satisfy the preference for treatment that reduces contaminant toxicity, mobility, or volume asa princip~ element.

The manner in which the IAAAP Soils OU #1 remedial action satisfies the above requirements isdiscussed in the following sections.

2.10.1 Protection of Human Health and the Environment

The selected remedy will provide for protection ofhuman health and the environment throughdestruction/degradation of explosives contamination to acceptable risk levels and throughmanagement of residual explosives, metals, and SVOC contaminants through landfilling.

2.10.2 Compliance with ARARs

The selected remedy will comply with applicable or relevant and appropriate requirements(ARARs). ARARs are presented in Table lSI, ISb, and ISc according to location-specific,chemical-specific, and action-specific requirements. Activities conducted entirely on-site donot require Federal, State, or local permits, but on-site actions must comply with thesubstantive requirements ofany Federal or State environmental laws that are ARARs. Off-siteactivities must meet conditions specified in the off-site facility's permits.

Significant ARARs associated with the selected remedy include:

Iowa Army Ammunition PlantSoils OU#1. Record of Decision (Revision No.1)IVl...1IPRO.IECT5-11H44_oNI44JoVlOln5N4ja_. 47 August 14, 1998

TABLE 15aCOMPLIANCE OF ALTERNATIVES WITH LOCATION-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

ARARCitation

Explosives Contaminated Soils

Thennal Treatment Biological Treatment

Explosives Plus Metals Contaminated Soils

Solidification/Stabilization withActivated Carbon

SVOC - Contaminated Soils

Off-site Disposal

..

Endangered Species Act, 16U.S.C. 1531 et seq.; andFish and Wildlife Coordination Act, 16 U.S.C. 661 etseq.

SO CFR Part 200, 50 CFR Part 402, and 33 CFR Parts320 - 330

Bald Eagle Protection Act, 16 U.S.C. 668 et seq.

Migratory Bird Treaty Act of 1972, 16 U.S.C. Section703

National Archeological and Historical PreservationAct, 16 U.S.C. Section 469

36 CFR Part 65

Native American Graves and Repatriation Act, 25U.S.C. Section 3001

Fish and Wildlife Coordination Act, 16 U.S.C. 661 etseq.

40CFR6.302

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\1Hes-11PR0JECTS-1\5tS44_aMl5644j11IROD\ARARS-a.wpd

Excavation and construction activities mayaffect habitat upon which the federally listedbald eagle or Indiana bat may depend.Measures will be taken to avoid affectingcritical habitat

Excavation and construction activities mayaffect habitat upon which the bald eagle maydepend. Measures will be taken to avoidaffecting the bald eagle's habitat. .

Excavation and construction activities mayadversely impact migratory bird speciespresent on or in the vicinity ofthe IAAAP.Measures will be taken to avoid such adverseimpacts.

Excavation and construction activities are notexpected to unearth. significant scientific,prehistoric, or archaeologic data. Ifsuchartifacts are discoveroo during excavationactivities, measures will be taken to avoidirreparable hann, loss or destruction oftheartifacts.

Excavation and construction activities are notexpected Native American graves or NativeAmerican cultural objects. Ifsuch graves orobjects are discovered during excavationactivities, measures will be taken to avoidtheir irreparable harm, loss or destruction.

Surface water removed from excavated areasor decontamination water may be dischargedto Brush, Long, or Spring Creeks. Ifso, thewater will be treated as necessary to avoidmodifying the creeks and affecting fish or.......

Excavation and construction activities mayaffect habitat upon which the federally listedbald eagle or Indiana bat may depend.Measures will be taken to avoid affectingcritical habitat

Excavation and construction activities mayaffect habitat upon which the bald eagle maydepend. Measures will be taken to avoidaffectin2 the bald e&21e's habitat.

Excavation and construction activities mayadversely impact migratory bird speciespresent on or in the vicinity ofthe IAAAP.Measures will be taken to avoid such adverseimpacts.

Excavation and construction activities are notexpected to unearth. significant scientific,prehistoric, or archaeologic data. Ifsuchartifacts are discovered during excavationactivities, measures will be taken to avoidirreparable hann, loss or destruction oftheartifacts.

Excavation and construction activities are notexpected Native American graves or NativeAmerican cultural objects. Ifsuch graves orobjects are discovered during excavationactivities, measures will be taken to avoidtheir irreparable hann, loss or destruction.

Surface water removed from excavated areasor decontamination water may be dischargedto Brush, Long, or Spring Creeks. If so, thewater will be treated as necessary to avoidmodifying the creeks and affecting tish or.. ... :..

Page 48

Excavation and construction activities mayaffect habitat upon which the federally listedbald eagle or Indiana bat may depend.Measures will be taken to avoid affectingcritical habitat

Excavation and construction activities mayaffect habitat upon which the bald eagle maydepend. Measures will be taken to avoidaffectin2 the bald ea2le's habitat.

Excavation and construction activities mayadversely impact migratory bird speciespresent on or in the vicinity ofthe IAAAP.Measures will be taken to avoid such adverseimpacts.

Excavation and construction activities are notexpected to unearth. significant scientific,prehistoric, or archaeologic data. Ifsuchartifacts are discovered during excavationactivities, measures will be taken to avoidirreparable hann, loss or destruction oftheartifacts.

Excavation and construction activities are notexpected Native American graves or NativeAmerican cultural objects. Ifsuch graves orobjects are discovered during excavationactivities, measures will be taken to avoidtheir irreparable harm, loss or destruction.

Surface water removed from excavated areasor decontamination water may be dischargedto Brush, Long, or Spring Creeks.•Ifso, thewater will be treated as necessary to avoidmodifying the creeks and affecting fish or. .:.. .

Excavation and construction activities mayaffect habitat upon which the fedefally listedbald eagle or Indiana bat may depend.Measures will be taken to avoid affectingcritical habitat

Excavation and construction activities mayaffect habitat upon which the bald eagle maydepend. Measures will be taken to avoidaffectin~ the bald eagle's habitat.

Excavation and construction activities mayadversely impact migratory bird speciespresent on or in the vicinity ofthe IAAAP.Measures will be taken to avoid such adverseimpacts.

Excavation and construction activities are notexpected to unearth significant scientific,prehistoric, or archaeologic data. Ifsuchartifacts are discovered during excavationactivities, measures will be taken to avoidirreparable hann, loss or destruction of theartifacts.

Excavation and construction activities are notexpected Native American graves or NativeAmerican cultural objects. Ifsuch graves orobjects are discovered during excavationactivities, measures will be taken to avoidtheir irreparable harm, loss or destruction.

Surface water removed from excavated areasor decontamination water may be dischargedto Brush, Long, or Spring Creeks. If so, thewater will be treated as necessary to avoidmodifying the creeks and affecting fish or

••••• ::. 1 nf?

August 14, 1998

!i..

\.,

TABLE 15aCOMPLIANCE OF ALTERNATIVES WITH LOCATION-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

Explosives Contaminated Soils Explosives Plw Metals Contaminated Soils SVOC - Contaminated Soils~.. :

ARAR Thermal Treatment Biological Treatment Solidification/Stabilization with Off-site DisposalCitation Activated Carbon

Fannland Protection Policy Act, 7 U.S.C. 4201 etseq. Prime and unique fannland may be present at Prime and unique fannland may be present at Prime and unique fannland may be present at Prime and unique fannland may be present atthe IAAAP. However, excavation and the IAAAP. However, excavation and the IAAAP. However, excavation and the IAAAP. However, excavation and

7 CPR. Part 658.4 and 658.5 constIuctioll activities are not expected to construction activities are not expected to construction activities are not expected to construction activities are not expected tooccur near such fannland. occur near such fannland. occur near such fannland. 9ccur near such fannland.

Iowa Environmental Quality Act, IA.C., Division Thennal treatment facilities will not be sited Biological treatment facilities will not be Treatment facilities will not be sited in Materials handling facilities will not be sited567, Title XI, Chapter 151, Iowa Hazardous Waste in critical wildlife habitat or prime fannland. sited iiJ. critical wildlife habitat or prime critical wildlife habitat or prime fannland. in critical wildlife habitat or prime farmland.Facilities Siting Regulations farmland.

IA.C. 151.3(2) and Table 1

Iowa Environmental Quality Act, IA.C., Division Thennal treatment facilities will not be sited Biological treatment facilities will not be Treatment facilities will not be sited within 1 Materials handling facilities will not be sited567, Title XI, Chapter 151, Iowa Hazardous Waste within 1 mile ofwet1ands. sited within 1 mile ofwetlands. mile ofwetlands. within 1 mile ofwet1ands.Facilities Siting Regulations

IA.C. 151.3(1)

Iowa Code Annotated, TItle XI, Natural Resources; Excavation and construction activities may Excavation and construction activities may Excavation and construction activities may Excavation and construction activities maySubtitle 6, Wildlife; Chapter 481A, Wildlife affect habitat upon which the federally listed affect habitat upon which the federally listed affect habitat upon which the federally listed affect habitat upon which the federally listedConservation bald eagle or Indiana bat may depend, or bald eagle or Indiana bat may depend, or bald eagle or Indiana bat may depend, or bald eagle or Indiana bat may depend, or

upon which the stat~listed orangethroat upon which the stat~listed orangethroat upon which the state-listed orangethroat upon which the state-listed orangethroatIA.C.481A.38 darter or yellow trout lily may depend. darter or yellow trout lily may depend. darter or yellow trout lily may depend. darter or yellow trout lily may depend.

Measures will be taken to avoid the "taking" Measures will be taken to avoid the "taking" Measures will be taken to avoid the "taking" Measures will be taken to avoid the "taking"ofwildlife. ofwildlife. ofwildlife. ofwildlife.

20f2

I'-

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August 14, 1998

o

TABLE ISbCOMPLIANCE OF ALTERNATIVES WITH CllEMICAL-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

A.RARCitation

Explosives Contaminated Soils

Thennal Treatment Biological Treatment

Explosives Plus Metals Contaminated Soils

Solidification/Stabilization withActivated Carbon

SVOC Contaminated Soils

OtT-Site Disposal

,..... .. , ...~ .

Iowa Underground Storage Tanks Acts, IA.C., .Division 567, Title X, Chapter 135, Iowa ..Underground Storage Tanks Regulations

IA.C.135.7(455BX9)

Petroleum Contamination Corrective Action Levels:U<:;::',·

Iowa Enviromnental Quality Act (lEQA), Division567, Title n, Chapter 28, Ambient Air QualityStandards

IA.C.28.1(455B)

[Ambient Air Quality Standards]

IEQA, Division 567, Title n, Chapter 22, ControllingPollution

IA.C. 22.3(3)

rvisible Emission Standard Set in Pennitl

IEQA, Division 567, Title n, Chapter 23, EmissionStandards for Contaminants

IA.C. 23.3(2Xa) and Table 1

[Emission Standard for Particulate Matter]

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\1H••1IPROJECTS-1\5444_el\SCS44j11IROD\ARARS-b.wpd

Compliance with the petroleum correctiveaction level of 100 mglkg will be achieved byoff-site disposal ofSVOC-contaminated soils.

lIDs alternative involves excavation andconstroction activities that may release leadand particulate matter into the air; andthermal treatment ofmetals/explosives­contaminated soils that may release lead andparticulate matter into the air. Controlequipment will be used to ensure compliancewith the ambient air quality standards.

This alternative involves the thennaltreatment ofcontaminated soils in a mobileunit, which is subject to new source review.Although the IAAAP is not required to obtaina pennit, it will need to meet the visible airemission standard that is IDNR's policy.

This alternative involves the thennaltreatment ofcontaminated soils, which is aprocess that may emit smoke, particulatematter, gaseous matter or other contaminants.Control equipment will be used to ensurecompliance with the emission standard torparticulate rnatter.

Compliance with the petroleum correctiveaction level of 100 mglkg will be achieved byoff-site disposal ofSVOC-contaminated soils.

This alternative involves excavation andconstroction activities that may release leadand particulate matter into the air.Engineering measures will be used to ensurecompliance with the ambient air qualitystandards.

This alternative does not involve new sourcereview.

This alternative does not involve emission ofparticulate matter from any process.

50

Compliance with the petroleum correctiveaction level of 100 mgIkg will be achieved byoff-site disposal ofSVOC-contaminated soils.

This alternative involves excavation andconstroction activities that may release leadand particulate matter into the air.Engineering measures will be used to ensurecompliance with the ambient air qualitystandards.

This alternative does not involve new sourcereview.

This alternative does not involve emission ofparticulate matter from any process.

Compliance with the petroleum correctiveaction level of 100 mglkg will be achieved byoff-site disposal ofSVOC-contaminated soils.

This alternative involves excavation andconstroction activities that may release leadand particulate matter into the air.Engineering measures will be used to ensurecompliance with the ambient air qualitystandards.

This alternative does not involve new sourcereview.

This alternative does not involve emission ofparticulate matter from any process.

10f5

August 14, 1998

TABLE ISbCOMPLIANCE OF ALTERNATIVES WITH CHEMICAL-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

.,' ,

ARARCitation

.. ::., :... ,.... . ..

Explosives Contaminated Soils

Thennal Treatment Biological Treatment

Explosives Plus Metals Contaminated Soils

Solidification/Stabilization withActivated Carbon

SVOC Contaminated Soils

Off-Site Disposal

.

.

ffiQA, Division 567, Title n, Chapter 23, EmissionStandards for Contaminants

IA.C.23.3(2Xc)(l)

[Emission Standard tor Fugitive Dust]

Federal Water Pollution Control Act (FWPCA), 33U.S.C. Section 402

[National Pollutant Discharge Elimination (NPDES)pennit conditions]

Safe Drinking Water Act (SDWA), 42 U.S.C. 300 etseq.

40 CFR 141.11; 40 CFR 141.15(a) and (b); 40 cm141.16(a); 40 CFR 141.61(c); and 40 CFR 141.61(b)

EPA, Office ofWater, "Drinking Water Regulationsand Health Advisories," October 1996

[Maximum Contaminant Levels (MCLs)l

SDWA, 42 U.S.C. 300 et seq.

40 CFR 141.50(a); and 40 CFR 141.51(b)

[Maximum Contaminant Level Goals (MCLGs)]

Iowa Anny Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\Hes- f\PROJECTS- fI5C744_8N\5644jll\RODIARARS-b.wpd

This alternative involves the excavation andonsite transport ofcontaminated soils, andconstruction activities, which may releaseparticulate matter into the air. Controlmeasures will be used to ensure compliancewith the fugitive dust standard for materialsto be handled, transported or stored, and forthe uselconstructionlrq>air ofconstructionhaul roads.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure that discharges comply with standardsin the NPDES pennit issued to the IAAAP.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLs.

.This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLGs.

This alternative involves the excavation andonsite transport ofcontaminated soils, andconstruction activities, which may releaseparticulate matter into the air. Controlmeasures will be used to ensure compliancewith the fugitive dust standard for materialsto be handled, transported or stored, and forthe uselconstructionlrq>air ofconstructionhaul roads.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure that discharges comply with standardsin the NPDES pennit issued to the IAAAP.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLs.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLGs.

51

This alternative involves the excavation andonsite transport ofcontaminated soils, andconstruction activities, which may releaseparticulate matter into the air. Controlmeasures will be used to ensure compliancewith the fugitive dust standard for materialsto be handled, transported or stored, and forthe uselconstructionlrq>air ofconstructionhaul roads.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure that discharges comply with standardsin the NPDES Dennit issued to the IAAAP.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLs.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLGs.

This alternative involves the excavation andonsite transport ofcontaminated soils, andconstruction activities, which may releaseparticulate matter into the air. Controlmeasures will be used to ensure compliancewith the fugitive dust standard for materialsto be handled, transported or stored, and forthe uselconstructionlrq>air ofconstructionhaul roads.

. ....

...

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure that discharges comply with standardsin the NPDES pennit issued to the IAAAP.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLs.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure compliance with the MCLGs.

20fS

August 14, 1998

TABLE ISbCOMPLIANCE OF ALTERNATIVES WITH CllEMICAWPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

Explosives Contaminated Soils Explosives Plus Metals Contaminated Soils SVOC Contaminated Soils

ARARCitation

Thermal Treatment Biological Treatment Solidification/Stabilization withActivated Carbon

Off-Site Disposal

..:...., ..

.. ::" ..::.::' :,.

'.00 ... :: .. ".:.:...:..

... '.:.'.:.' ..:.. : .. , ....., ,',

ffiQA, lA.C., Division 567, Title ill, Chapter 62,Effluent and Pretreatment Standards: Other EffluentLimitations or Prohibitions

IA.C.62.1(455B)(I)

rNPDES pennit conditionsl

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with standards inthe NPDES pennit issued to the lAMP.

This alternative may involve the discharge ofsUlface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with standards inthe NPDES pennit issued to the IAAAP.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with standards inthe NPDES pennit issued to the IAAAP.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with standards inthe NPDES pennit issued to the IAAAP.

ffiQA, lA.C., Division 567, Title ill, Chapter 41,Iowa Drinking Water Regulations

IA.C. 4I.3(455B)(I)(b); 4I.3(455B)(5)(a) and (b);and 41.3(455B)(6)(a)

rstate MCLs1

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure water quality complies with the stateMCLs.

This alternative may involve the discharge ofsUlface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure water quality complies with the stateMCLs.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure water quality complies with the stateMCLs.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure water quality complies with the stateMCLs.

ffiQA, IA.C., Division 567, Title IV, Chapter 61, .Surface Water Quality Criteria

IA.C.612(455B)(2)

rAntidesuadation Policvl

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with the stateantide2radation policy.

This alternative may involve the discharge ofsUlface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with the stateantidesuadation policy.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with the stateantidegradation policy.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. Appropriate treatment willensure discharges comply with the stateantid..-....,t"tion policy.

ffiQA, lA.C., Division 567, Title IV, Chapter 61,Surface Water Quality Criteria

IA.C.61.3(455B)

[Water Quality Criteria for general use segments, andfor designated use water segments]

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. The discharge will betreated appropriately to ensure compliancewith the state water quality criteria for ClassB(LR) waters.

This alternative may involve the discharge ofsUlface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. The discharge will betreated appropriately to ensure compliancewith the state water quality criteria for ClassB(LR) waters.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. The discharge will betreated appropriately to ensure compliancewith the state water quality criteria for ClassB(LR) waters.

This alternative may involve the discharge ofsurface water removed from excavated areas,or decontamination water, into Brush, Long,or Spring Creeks. The discharge will betreated appropriately to ensure compliancewith the state water quality criteria for ClassB(LR) waters.

30f5

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August 14, 1998

TABLE ISbCOMPLIANCE OF ALTERNATIVES WITH CHEMICAJ,SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

ARARCitation

Explosives Contaminated Soils

Thennal Treatment Biological Treatment

Explosives Plus Metals Contaminated Soils

Solidification/Stabilization withActivated Carbon

SVOC Contaminated Soils

Off-Site Disposal

.: ..

SDWA, 42 U.S.C. 300 et seq.

40 CFR 141.11; 40 CFR 141.15(a) and (b); 40 CFR141.16(a); 40 CFR 141.61(c); and 40 CFR 141.61(b)

EPA, Office ofWater, "Drinking Water Regulationsand Health Advisories," October 1996

[MCLs]

SDWA,42 U.S.C. 300 et seq.

40 CFR 141.50(a); and 40 CFR 141.51(b)

[MCLGs]

Solid Waste Disposal Act, as amended by theResource Conservation and Recovery Act (RCRA), 42U.S.C. 6901 et seq.

40 CFR258.40(a)(I), and Table 1

[Groundwater Protection Standards for solid wastedisposal facilitiesl

Solid Waste Disposal Act, as amended by the RCRA,42 U.S.C. 6901 et seq.40 CFR 264.92 - 264.94, and Table 1

[Groundwater Protection Standards for pennittedhazardous waste facilities]

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\1H••1IPROJECTS-1\5G44_8N\.5G44jl1\ROD\ARARS-b.wpd

This alternative includes the onsite disposaloftreatment residuals into an on-site landfill.This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with MCLs.

This alternative includes the onsite disposaloftreatment residuals into an on-site landfill.This rnay present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with MCLGs.

This alternative includes the onsite disposaloftreatment residuals into an on-site landfill.This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with the groundwater protectionstandards.

This alternative includes the onsite disposalof treatment residuals into an on-site landfill.

This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with the groundwater protectionstandards.

This alternative may include the onsitedisposal of treatment residuals into an on-sitelandfIll. This may present a potential forleaching ofcontaminants into thegroundwater, which is a potential source ofdrinking water. Groundwater monitoring willensure compliance with MCLs.

This alternative may include the onsitedisposal of treatment residuals into an on-sitelandfIll. This may present a potential forleaching ofcontaminants into thegroundwater, which is a potential source ofdrinking water. Groundwater monitoring willensure compliance with MCLGs.

This alternative may include the onsitedisposal oftreatment residuals into an on-sitelandfIll. This may present a potential forleaching ofcontaminants into thegroundwater, which is a potential source ofdrinking water. Groundwater monitoring willensure compliance with the groundwaterprotection standards.

This alternative may include the onsitedisposal of treatment residuals into an on-sitelandfill. This may present a potential forleaching ofcontaminants into thegroundwater, which is a potential source ofdrinking water. Groundwater monitoring willensure compliance with the groundwaterprotection standards.

53

This alternative includes the onsite di~osal

oftreatment residuals into an on-site landfill.This may present a potential for leaching ofcontaminants into the groundwater, Which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with MCLs.

This alternative includes the onsite disposaloftreatment residuals into an on-site landfill.This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with MCLGs.

This alternative includes the onsite disposalof treatment residuals into an on-site landfill.This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with the groundwater protectionstandards.

This alternative includes the onsite disposalof treatment residuals into an on-site landfill.

This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with the groundwater protectionstandards.

This alternative does not involve on-sitedisposal ofSVOC contaminated soil.

This alternative does not involve on-sitedisposal ofSVOC contaminated soil.

This alternative does not involve on-sitedisposal ofSVOC contaminated soil.

This alternative does not involve on-sitedisposal ofSVOC contaminated soil.

40f5

August 14, 1998

TABLE ISbCOMPLIANCE OF ALTERNATIVES WITH CllEMICAL-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

ARARCitation

Explosives Contaminated Soils

Thermal Treatment Biological Treatment

Explosives Plus Metals Contaminated Soils

Solidification/Stabilization withActivated Carbon

SVOC Contaminated Soils

Off-Site Disposal

...... , ,.' ,., ........',.' ..

........,.,.,", ...,..... "." ..

mQA, IA.C., Division 567, Title ill, Chapter 41,Iowa Drinking Water Regulations

IA.C. 41.3(455B)(I)(b); 41.3(455B)(5)(a) and (b);and 41.3(455B)(6)(a)

rstate MCLsl

mQA, IA.C., Division 567, Title X, Chapter 133,Iowa Responsible Parties Cleanup Regulations

IA.C. 133.4(455B,455E)(2) and (3)(b)(1)

[Action Levels for groundwater cleanup actions]

Iowa Army Ammunition PlantSoils OU#1, Record ofDecision (Revision No.1)\1He.1IPROJECTS-1\544'CaI\.5644j11IROD\ARARS-b.wpd

This alternative includes the onsite disposaloftreatment residuals into on-site landfill.This may present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with the state MCLs.

This alternative includes the onsite disposaloftreatment residuals into an on-site landfill.This may result in point source contaminationpresenting a significant risk to groundwater,through leaching ofcontaminants.Groundwater monitoring will ensurecompliance with the state action levels.

This alternative may include the onsitedisposal oftreatment residuals into an on-sitelandfIll. This may present a potential forleaching ofcontaminants into thegroundwater, which is a potential source ofdrinking water. Groundwater monitoring willensure compliance with the state MCLs.

This alternative may include the onsitedisposal oftreatment residuals into an on-sitelandfIll. This may result in point sourcecontamination presenting a significant risk togroundwater, through leaching ofcontaminants. Groundwater monitoring willensure compliance with the state actionlevels.

54

This alternative includes the onsite disposalof treatment residuals into on-site landfill.This rnay present a potential for leaching ofcontaminants into the groundwater, which is apotential source ofdrinking water.Groundwater monitoring will ensurecompliance with the state MCLs.

This alternative includes the onsite disposaloftreatment residuals into an on-site landfill.This may result in point source contaminationpresenting a significant risk to groundwater,through leaching ofcontaminants.Groundwater monitoring will ensurecompliance with the state action levels.

This alternative does not involve on-sitedisposal ofSVOC contaminated soil.

This alternative does not involve on-sitedisposal ofSVOC contaminated soil.

50f5

August 14, 1998

TABLE IScCOMPLIANCE OF ALTERNATIVES WITH ACTION-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

ARARCitation

Explosives Contaminated Soils

Thermal Treatment Biological Treatment

Explosives Plus Metals Contaminated Soils

Solidification/Stabilization withActivated Carbon

SVOC Contaminated Soils

Off-Site Disposal

CERCLA Section 121 (b)

[Preference for treatment]

Solid Waste Disposal Act, as amended by theResource Conservation and Recovery Act (RCRA), 42U.S.C. 6901 et seq.

40 CFR 268 Subparts A and D

rLand Disposal Restrictionsl

Iowa Environmental Quality Act (lliQA), IA.C.,Division 567, TItle X, Chapter 141, Hazardous Waste

40 CFR261.21 - 261.24, and Table 1 (adopted atIA.C. 141.2[1])

[Criteria for Identifying the Chamcteristics ofRCRAHazardous Wastes]

IEQA, IA.C., Division 567, Title X, Chapter 141,Hazardous Waste

40 CFR 261.32 (adopted at IA.C. 1412[1])

[Criteria for Listing RCRA Hazardous Wastes]

Iowa Anny Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)l\Hell-1IPROJECTS-115CJ4.f_81f15644jaIRODIARARS-c.wpd

This alternative involves thermal treatment ofcontaminated soils. This alternative ensurescompliance with CERCI~.'s preference fortreatment, and compliance with theestablished 50 percent treatment goal.

This alternative may involve disposal to alandf111 ofmetals - contaminated soils thathave been solidified and stabilized. Ifthesecontaminated soils are restricted from landdisposal, alternative treatment levels will bemet before diSposal in a landfl1l.

Excavated soils will be identified as eitherRCRA or non-RCRA hazardous wastes. Thisalternative will comply with the relevant andappropriate action-specific requirementswithin the state's hazardous waste program.

Prior to placement iIi. the CAMU, excavatedsoils will be tested to determine ifthe listedRCRA hazardous waste K047 is present(based on ignitability). This alternative willcomply with the relevant and appropriateaction-specific requirements within the state'shazardous waste program.

This alternative involves biological treatmentofcontaminated soils. This alternativeensures compliance with CERCLA'spreference for treatment, and compliance withthe established 50 percent treatment goal.

This alternative may involve disposal to alandflll ofmetals - contaminated soils thathave been solidified and stabilized. Ifthesecontaminated soils are restricted from landdisposal, alternative treatment levels will bemet before disposal in a landfl1l.

Excavated soils will be identified as eitherRCRA or non-RCRA hazardous wastes. Thisalternative will comply with the relevant andappropriate action-specific requirementswithin the state's hazardous waste program.

Prior to placement in the CAMU, excavatedsoils will be tested to detennine if the listedRCRA hazardous waste K047 is present(based on ignitability). This alternative willcomply with the relevant and appropriateaction-specific requirements within the state'shazardous waste program.

55

This alternative involvessolidification/stabilization ofcontaminatedsoils. This alternative ensures compliancewith CERCLA's preference for treatment, andcompliance with the established 50 percenttreatment20al.

This alternative rnay involve disposal to alandf111 ofmetals - contaminated soils thathave been solidified and stabilized. Ifthesecontaminated soils are restricted from landdisposal, alternative treatment levels will bemet before disposal in a landfl1l.

Excavated soils will be identified as eitherRCRA or non-RCRA hazardous wasteS. Thisalternative will comply with the relevant andappropriate action-specific requirementswithin the state's hazardous waste program.

Prior to placement in the CAMU, excavatedsoils will be tested to determine ifthe listedRCRA hazardous waste K047 is present(based on ignitability). This alternative willcomply with the relevant and appropriateaction-specific requirements within the state'shazardous waste program.

This alternative involves disposal to a landflllofcontaminated soils. Ifthese contaminatedsoils are restricted from land disposal,alternative treatment levels will be met beforedisposal in a landflll.

This alternative involves disposal to a landflllofcontaminated soils. Ifthese contaminatedsoils are restricted from land disposal,alternative treatment levels will be met beforedisposal in a landfl1l.

Excavated soils will be identified as eitherRCRA or non-RCRA hazardous wastes. Thisalternative will comply with the relevant andappropriate action-specific requirementswithin the state's hazardous waste program.

Prior to placement in the CAMU, excavatedsoils will be tested to determine ifthe listedRCRA hazardous waste K047 is present(based on ignitability). This alternative willcomply with the relevant and appropriateaction-specific requirements within the state'shazardous waste program.

lof4

August 14, 1998

TABLE 15cCOMPLIANCE OF ALTERNATIVES WITH ACTION-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

", Explosives Contaminated Soils Explosives Plus Metals Contaminate~ Soils SVOC Contaminated Soils

ARAR Thermal Treatment Biological Treatment Solidification/Stabilization with Off-Site DisposalCitation Activated Carbon

IEQA, LA.C., Division 567, Title X, Chapter 141, Unauthorized persons and livestock will be Unauthorized persons and livestock will be Unauthorized persons and livestock will be Unauthorized persons and livestock will beHazardous Waste restricted from all active portions of the restricted from all active portions of the restricted from all active portions ofthe restricted from all active portions of the

IAAAP during soil remediation actions, using IAAAP during soil remediation actions, using IAAAP during soil remediation actions, using IAAAP during soil remediation actions, using40 CFR264.14 (adopted atlA.C. 141.5[455B» fencing and site control measures. fencing and site control measures. fencing and site control measures. , fencing and site control measures.

[Security Requirements]

IEQA, LA.C., Division 567, Title X, Chapter 141,' Contaminated soils may be incompatible with Contaminated soils may be incompatible with Contaminated soils may be incompatible with Contaminated soils may be incompatible withHazardous Waste each other or with hazardous wastes in the each other or with hazardous wastes in the each other or with hazardous wastes in the each other or with hazardous wastes in the

soil repository; or hazardous based on the soil repository; or hazardous based on the soil repository; or hazardous based on the soil repository; or hazardous based on the40 CFR264.17(a) and (b)(adoJ>ted atlA.C. characteristics of ignitability or reactivity. characteristics of ignitability or reactivity. characteristics of ignitability or reactivity. characteristics of ignitability or reactivity.141.5[455B» Precautions will be taken to prevent Precautions will be taken to prevent Precautions will be taken to prevent Precautions will be taken to prevent

accidental ignition or reaction ofignitable or accidental ignition or reaction of ignitable or accidental ignition or reaction of ignitable or accidental ignition or reaction of ignitable or[General Requirements for Ignitable, Reactive, or reactive wastes. reactive wastes. reactive wastes. reactive wastes.IncoJll1)atible Wastesl

IEQA, IA.C., Division 567, Title X, Chapter 141, This alternative involves the disposalof This alternative may involve the disposal of This alternative involves the disposal of This alternative does not involve on-siteHazardous Waste certain treated contaminated soils into a treated and untreated contaminated soils into certain treated contaminated soils into a disposal ofSVOC contaminated Soil.

landfIll which is a land disposal unit a landfIll which is a land disposal unit landfIll which is a land disposal unit40 CFR Part 264, Subpart F (adopted at LA.C. Measures will ensure this alternative will Measures will ensure the alternative will meet Measures will ensure this alternative will141.5[455B» meet the groundwater protection the groundwater protection requirements. meet the groundwater protection

requirements. requirements.[Groundwater Protection Requirements for Disposalin a Land DisPOsal Unitl

IEQA, I.A.C., Division 567, Title X, Chapter 141, This alternative involves the disposal of This alternative may involve the disposal of This alternative involves the disposal of This alternative does not involve on-siteHazardous Waste certain treated contaminated soils into a treated and untreated contaminated soils into certain treated contaminated soils into a disposal ofSVOC contaminated Soil.

laildfIll. The alternative will comply with the a landfIll. The alternative will comply with landfill. The alternative will comply with the40 CFR Part 264, Subpart G (adopted at LA.C. closure and post-closure requirements when the closure and post-closure requirements closure and post-closure requirements when141.5[455B» the so!l repository is closed. when the soil repository is closed. the soil repository is closed.

rClosure and Post-Closure Reauirementsl 20f4

Iowa Army Ammunition PlantSoils 0U#1, Record of Decision (Revision No.1)1\He$-1IPROJECTS-1ISCS44_811\SC44jeIRODIARARS-c.wpd 56

August 14, 1998

TABLE 1ScCOMPLIANCE OF ALTERNATIVES WITIIACTION-SPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

ARARCitation

Explosives Contaminated Soils

Thermal Treatment Biological Treatment

. i

Explosives Plus Metals Contaminate4 Soils

I

Solidification/Stabilization witliActivated Carbon

SVOC Contaminated Soils

Off-8ite Disposal

lliQA, lA.C., Division 567, Title X, Chapter 141,Hazardous Waste

40 CFR Part 264, Subpart I (adopted at IA.C.141.5[455B»

[Requirements for Use and Management ofContainers]

lliQA, lA.C., Division 567, Title X, Chapter 141,Hazardous Waste

40 CFR Part 264, Subpart L (adopted at IA.C.141.5[455B»

[Requirements for Storage ofHazardous Waste inPiles]

lliQA, IA.C., Division 567, Title X, Chapter 141,Hazardous Waste

40 CFR Part 264, Subpart N (adopted at IA.C.141.5[455B»

[Requirements for Disposal ofHazardous Waste inLandfills]

lliQA, I.A.C., Division 567, Title X, Chapter 141,Hazardous Waste

40 CFR Part 264, Subpart 0 (adopted at lA.C.141.5[455B»

[Requirements for Incineration ofHazardous Waste]

Iowa Anny Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)l\He$-1IPROJECTS-11SG4<CeMl5G44jaIRODlARARS-c.wpd

Surface water from excavated areas, anddecontamination water may result from thisalternative. Storage ofthese waters incontainers would be necessary until treatmen~and/or disposal could occur. The alternativewill comply with the requirements for the useand management ofcontainers.

Excavated soils may be temporarily stored inpiles prior to treatment and/or disposal. Thisalternative will comply with the requirementsfor storage ofhazardous waste in piles.

This alternative involves the disposal ofcertain treated contaminated soils into alandfIll. The alternative will comply with thedisposal requirements.

This alternative may involve the incinerationofcontaminated soils. Incineration willcomply the performance, operating andmonitOring requirements.

Surface water from excavated areas, anddecontamination water may result from thisalternative. Storage of these waters incontainers would be necessary until treatmentand/or disposal could occur. The alternativewill comply with the requirements for the useand management ofcontainers.

·Excavated soils may be temporarily stored inpiles prior to treatment and/or disposal. Thisalternative will comply with the requirementsfor storage ofhazardouswas~ in piles.

This alternative may involve the disposal oftreated and untreated contaminated soils intoa landfIll. The alternative will comply withthe disposal requirements.

This alternative does not involve theincineration ofcontaminated soils.

57

Surface water from excavated areas, anddecontamination water may result from (thisalternative. Storage of these waters in .containers would be necessary until treatmentand/or disposal could occur. The alternativewill comply with the requirements for the useand management ofcontainers.

Excavated soils may be temporarily stored inpiles prior to treatment and/or disposal. Thisalternative will comply with the requirementsfor storage ofhazardous waste in piles.

This alternative involves the disposal ofcertain treated contaminated soils into alandftll. The alternative will comply with thedisposal requirements.

,

This alternative does not involve theincineration ofcontaminated soils.

Surface water from excavated areas, anddecontamination water may result from thisalternative. Storage ofthese waters incontainers would be necessary until treatmentand/or disposal could occur. The alternativewill comply with the requirements for the useand management ofcontainers.

Excavated soils may be temporarily stored inpiles prior to treatment and/or disposal. Thisalternative will comply with the requirementsfor storage ofhazardous waste in piles.

This alternative may involve the disposal oftreated and untreated contaminated soils intoan ofT-site landftll. The alternative willcomply with the disposal requirements.

This alternative does not involve theincineration ofcontaminated soils.

30f4

August 14, 1998

TABLE 1ScCOMPLIANCE OFALTERNATIVES WITH ACTION-sPECIFIC ARARS

IOWA ARMY AMMUNITION PLANT, MIDDLETOWN, IOWA

Explosives Contaminated Soils Explosives Plus Metals Contaminated Soils SVOC Contaminated Soils

ARAR Thermal Treatment Biological Treatment Solidification/Stabilization with Off-Site DisposalCitation Activated Carbon

mQA, IA.C., Division 567, Title X, Chapter 141, Contaminated soils will be stockpiled in a Contaminated soils will be stockpiled in a Contaminated soils will be stockpiled in a Contaminated soils will be stockpiled in aHazardous Waste CAMU prior to treatment. This alternative CAMU prior to treatment. This alternative CAMU prior to treatment. This alternative CAMU prior to treatment. This alternative

will comply with the substantive will comply with the substantive will comply with the substantive will comply with the substantive40 CFR Part 264, Subpart S (adopted at IA.C. requirements for CAMUs. requirements for CAMUs. requirements for CAMUs. requirements for CAMUs.141.5[455B])

[Corrective Action for Solid Waste ManagementUnits]

ffiQA, IA.C., Division 567, Title X, Chapter 141, This alternative does not involve composting This alternative may involve composting of This alternative does not involve composting This alternative does not involve compostingHazardous Waste ofcontaminated soils in containment contaminated soils in containment buildings. ofcontaminated soils in containment ofcontaminated soils in containment

buildings. The alternative will comply with design and buildings. buildings40 CPR Part 264, Subpart DD (adopted at IA.C. operating standards, and closure and post-141.S[455B» closure care.

[Requirements for Composting ofHazardous Waste inContainment Buildings]

ffiQA, IA.C., Division 567, TItle II, Chapter 23, This alternative involves the excavation of This alternative involves the excavation of This alternative involves the excavation of This alternative involves the excavation ofEmission Standards for Contaminants contaminated soils and the transport of these contaminated soils and the transport of these contaminated soils and the transport of these contaminated soils and the transport ofthese

soils to either treatment or disposal areas. soils to either treatment or disposal areas. soils to either treatment or disposal areas. soils to either treatment or disposal areas.IA.C. 23.3(2)(c)(1) The alternative also involves construction The alternative also involves construction The alternative also involves construction The alternative also involves construction

activities. Control measures will be activities. Control measures will be activities. Control measures will be activities. Control measures will be[Fugitive Dust Controls] implemented to limit fugitive dust emissions implemented to limit fugitive dust emissions implemented to limit fugitive dust emissions implemented to limit fugitive dust emissions

that may result from remedial actions. that may result from remedial actions. that may result from remedial actions. that may result from remedial actions.

40f4

Iowa Anny Ammunition PlantSoils DU#1, Record of Decision (Revision No.1)\1He.s-1IPROJECT&1\5G44_811\.5G44je\ROD\ARAR&c.wpd 58

August 14, 1998

• Chemical - specific ARARs relating to ambient air quality standards specified underlAC 28.1 (455B), visible emission standards specified under lAC 22.3 (3), particulateemission standards specified under lAC 23.3 (2) (a) and Table 1, and fugitive dustemissions standards specified under lAC 23.3 (2) (c) (1).

• CERCLA's preference for treatment specified under Section 121 (b).

• Land Disposal Restrictions for treated soils and residues specified under 40 CPR 268Subparts A and D.

• Requirements for incineration of hazardous waste specified under 40 CPR 264, Subpart0, for the selected remedy.

• Requirements for composting of hazardous waste in buildings specified under 40 CPRPart 264, Subpart DD, for the contingent remedy.

• Requirements for surface water quality criteria and discharge limitations specified underlAC 61.3 (455B) and 33 USC Section 402.

2.10.3 Cost Effectiveness

The selected remedy is cost-effective because it provides overall effectiveness proportional to its costs.LTID Thermal Treatment, the preferred technology for treatment of explosives-contaminated soils,

appears to be the least costly technology based on information currently available. If a combustionfacility risk assessment and additional process development and economic evaluations show that LTTDThermal Treatment cannot be conducted in a protective manner, appropriate documentation will beprepared for review and submitted to the administrative record, and the contingency remedy ofBiologicalTreatment will be implemented. Solidification/stabilization ofexplosives plus metals contaminated soilsand off-site disposal of SVOC-contaminated soils provides overall protectiveness equivalent to otheralternatives, at lower costs.

2.10.4 Use of Permanent Solutions and Alternative TreatmentTechnologies to the Maximum Extent Practicable

Superfund specifies a preference for utilization of permanent solutions and innovative treatmenttechnologies or resource recovery technologies to the maximum extent practicable. The selected remedialaction permanently destroys or degrades and stabilizes contaminants in explosives-contaminated soils, andpermanently stabilizes contaminants in explosives plus metals contaminated soils. Off-site disposal ofSVOC-contaminated soil contains contaminants rather than degrading them, and requires long-termlandfill operation and maintenance to ensure continued effectiveness. On-site treatment for this smallvolume of SVOC-contaminated soil was determined to be not cost effective. The Army and EPA believe

Iowa Army Ammunition PlantSoils OU#1. Record of Decision (Revision No.1)

59August 14, 1998

the preferred alternative provides the best balance of trade-offs among the alternatives withrespect to the evaluating criteria.

2.10.5 Preference for Treatment Which Reduces Toxicity, Mobility, orVolume

Both LTID Thermal Treatmentand Biological Treatmentwill reduce explosives contaminantlevels below remediation goals, although Thermal Treatment will provide a greater degree ofreduction in contaminant toxicity and mobility. LTID and bio-slurry treatment are notexpected to change soil volumes significantly as a result oftreatment; composting will resultin a volume increase of 150 to 200%. Solidification/stabilization of explosives plus metalscontaminatedsoils andoff-sitedisposal ofSVOC-contaminatedsoilswill providefor reductionof contaminant mobility only.

2.11 Documentation of Significant Changes

The Proposed Plan specified management of thermal treatment residuals in the SoilRepository. This ROD provides for the potential managementofthese residuals outside oftheSoil Repository in an appropriate manner protective of human health and the environment.Thermal treatment will destroy contaminants and, therefore, disposal of thermal treatmentresiduals outside the Soil Repository will not comprise protection under this alternative. Thisdisposal method will save landfill space which may be better used for more highlycontaminated materials from other sources and, therefore, is considered cost effective.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\H...'IPItOlEc:rS-'I5IU_-'\lI~._."'IIcl 60 August 14, 1998

3.0 RESPONSIVENESS SUMMARY

The Proposed Plan for fmal action for the Soils OU #1 was released to the public on June 20, 1998.A public comment period was held from June 20, 1998 to July 20, 1998. During this period, nocomment letters were received. In addition, a public meeting was held on July 9, 1998. At thismeeting representatives from the Army and EPA were available to the public to discuss concerns,accept comments, and answer questions regarding the preferred alternative presented in the ProposedPlan.

This Responsiveness Summary serves two functions First, it summarizes the comments ofthe public.Second, it provides responses to the comments on the Proposed Plan that were made at the publicmeeting.

3.1 Overview

The preferred alternative selected jointly by the Army and EPA and presented in the Proposed Planinvolved on-site LTTD Thermal Treatmentofexplosives-contaminatedsoils as the preferred remedy,with Biological Treatment as the contingency remedy pending results of feasibility testing and fielddemonstrations. The preferred alternative also included on-site solidification/stabilization ofexplosives plus metals contaminated soils and off-site disposal of SVOC-contaminated soil.

Verbal public comments on the preferred alternative were documented at the public meeting on July9, 1998. No written comment letters were received during the public comment period.

Commentors expressed interest in the following issues:

• Alternative equipment for LTTD (use of existing on-site incinerators; use ofmobileequipment).

• Usability of soil after treatment.

• Health risks of LTID treatment

• Transportation and off-site disposal locations for SVOC - contaminated soil.

3.2 Background on Community Involvement

Overall, the opportunities for participation of local stakeholders in CERCLA actions have beenprovided through two principal mechanisms. First, documents prepared that lead to decisions haveundergonepublic commentperiods, with documentavailability announced in thelocal media. Second,an IAAAP Restoration Advisory Board (RAB) has been established to enable the community and

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\\H...lIPl1OlECT5-1151U__.,.VlClO'45N4l'JOClIl2.wpd 61 August 14, 1998

representatives of government agencies to meet and exchange information about the IAAAP'senvironmental cleanup program and to provide the community an opportunity to review progress andparticipate in dialogue with decision makers.

The RIlFS and Proposed Plan for the Interim Soils OU were released to the public in November 1996and May 1997, respectively. A public comment period was held from May 28, 1997 to June 30, 1997.In addition, a public meeting was held on June 5, 1997 at theDanville Community Center. There wereno written or verbal comments regarding the Proposed Plan submitted to the Army at this meeting orduring the comment period.

This Final FS and Proposed Plan for Soils OU#1 went through a similar public review and comment,in compliancewith NEPA. The Proposed Plan for fmal action for the Soils OU #1was released to thepublic on June 20, 1998. This document was made available to the public in both the administrativerecord and the site information repositories. The notice of availability for the Proposed Plan waspublished in the Burlington Hawk Eye on June 20, 1998 and later published in the Ft. Madison DailyDemocrat. A public comment period was held from June 20, 1998 to July 20, 1998. In addition, apublic meeting was held on July 9, 1998 at the pzazz Best Western Motor Inn in Burlington, Iowa.At this meeting representatives from the Army and EPA were available to the public to discussconcerns, accept comments, and answer questions regarding the preferred alternative presented in theProposed Plan. Comments submitted to the~ywere considered in final selection ofthe remedialaction.

TheRAB was OIganized inmid-1997 and has held public meetings generally monthly. Typically thesemeetings include environmental cleanup progress reports, explanations ofthe regulatory process, andinformation81 handouts and exhibits. Tapes, minutes, and attendance at the meetings is available fromthe IAAAP Environmental Affairs Office.

Documents prepared as part of removal or remedial actions at IAAAP have be placed in the siteAdministrative Record file, which is located in the following public information repositories:

Iowa Army Ammunition PlantVisitor Reception AreaBuilding 100-101Middletown, Iowa 52683-5000(319) 753-7710

Iowa Army Ammunition PlantSoils OU#1. Record of Decision (Revision No.1)l'It"'I\PIIO.IECT$.I15MC_~~• .rodlI2.""" 62

Burlington Public Library501 N. Fourth StreetBurlington, Iowa 52601(319) 753-1647

August 14, 1998

..

Danville City Hall105 W. ShepardDanville, Iowa 52623(319) 392-4685

The Army has coordinated selection ofthis remedial action with the U.S. Environmental ProtectionAgency (EPA). The Army is the lead agency for implementing the remedial action at the IAAAP.As the support agency, the EPA oversees the cleanup activities conducted by the Army to ensure thatrequirements ofCERCLAISARA, the NCP, and the Federal Facilities Agreement between the Armyand the EPA have been met The State ofIowa has declined to participate in the review ofCERCLAclean up activities at the IAAAP.

3.3 Summary of Public Comments and Agency Responses

This responsiveness summary includes statements made at the July 9, 1998 public meeting (noadditional comments were submitted in writing during the comment period). It also includes Armyand EPA responses to those comments and questions. Comments and questions have beenparaphrased or quoted in italic text. Every attempt has been made to accurately preserve the intent ofthe comment and to include all issues raised. Individual comments are grouped into common issuesto avoid repetitiveness in responses.

ISSUE 1: Can existing on-site incinerators be usedfor treatment ofcontaminatedsoil?

Dueto differences inmaterials handlingrequirements, volumes, and operating conditions, existingon­site incinerators are not suitable for treatment of contaminated soils. Permitting issues and airemission control requirements would also be significantly different. The selected remedy usesequipment specifically designed for treating contammated soils.

ISSUE 2: Will the selectedremedy destroyorganismspresent in the soil, makingitdifficult to useitfor anything?

LTID will degrade other organic compounds in the soil in addition to degrading explosives. Thedegree of degradation will depend on the characteristics of particular compound (Le., boiling point,vapor pressure) and the operating conditions used for the LTTD unit. LTTD exposes contaminatedsoil to amuch lower temperature than incineration (typically 200 to 600 Of in the primary chamberforLTID vs. 1400 to 1800 Of for incineration). While these LTID operating conditions are known tobe effectivefor destroyingexplosives contamination, information is notnecessarily availableto predictthe degree ofdestruction for other, desirable, organic compounds. However, LTTD typically does notproduce as much of a volume reduction as incineration and therefore can be presumed to be less .destructive than incineration. Contaminated soil requiring treatment is primarily clay, so loss ofproductivity will be less significant than if it were primarily topsoil.

Iowa Army Ammunition PlantSoils OU#1, Record of Decision (Revision No.1)\1H_~ROJECT$-1__~VI~_."'INI 63 August 14, 1998

ISSUE 3: To minimize capital costs, will treatment equipment be reusable at otherfacilities?

The LTID treatment equipment will be modular, trailer-mounted, mobile equipment brought to thesite and operated by a contractor specializing in providing soil remediation services. While theequipment may require special modifications to adapt to site-specific conditions, it likely will havebeen used previously at other sites and will be intended for use again elsewhere in the future. TheArmy will be purchasing a service rather than purchasing a piece of equipment.

ISSUE4: Have sitesbeen identifiedforoff-sitedisposalofSVOC-contaminatedsoil? How wouldthe soil be transported? How can we visualize a volume of200 cubic yards?

Cost estimates presented in the Proposed Plan and ROD were based on conversations withrepresentatives from three commercial waste disposal companies: American Waste Group, LaidlawEnvironmental Services of Illinois, Inc., and Waste Management, Inc. Disposal could be at any ofseveral licensed waste disposal facilities operated by these or other companies. Competitive bids willbe solicited prior to actual implementation, and a specific contractor and disposal facility will beidentified at that time. Transportationwould most likely be by truck. The largest roll-offbox typicallyused for over-the-highway transportation of wastes has a volume of approximately 20 cubic yards.Assuming they are typically loaded half-full (10 cubic yards each), 200 cubic yards represents about20 truckloads. Viewed another way, 200 cubic yards represents a block 151 by 151 by 241 indimensions.

ISSUE 5: Will the proposed cleanup process produce additional carcinogens that the publicshould be aware oft Will the L17D unit have continuous monitoring ofair emissions?

LITD operates by volatilizing contaminants in the soil (heating them until they are converted to agaseous state) and burning them under controlled conditions in a secondary combustion chamber.Combustion results in essentially complete destruction ofcontaminants to carbon dioxide and water.However, no process in 100% efficient, and trace amounts of byproducts (products of partialcombustion) may be expected to remain. The LTID unit will be equipped with appropriate airemission control facilities, such as filters and wet scrubbers, to clean the off-gases prior to release tothe atmosphere. Thespecific operating conditions ofthe LITD unit (i.e., temperature, residence time,oxygen requirements) will be determined based on a trial bum, with the purpose of maximizingcontaminant destruction as required to protect human health and the environment. In addition, acombustion risk assessment will be completed prior to implementation ofthe selected remedy. Thecombustion risk assessment is intended to identify potential byproducts and, through an evaluation ofsite-specific conditions such as prevailing winds, evaluate the .potential impacts on receptors. Theresults of the risk assessment will be used to establish requirements for safe operation to controlunacceptable risks. The combustion risk assessmentwill be reviewed by experts within both the Armyand EPA who are experienced in thermal treatment of explosives-contaminated soils at otherinstallations. Emissions monitoring during operation will ensure that the unit is operated incompliance with the requirements established by the risk assessment. Army and EPA representatives

Iowa Army Ammunition PlantSolla OUlt. Record of Decision (Revision No. t).....'"OIICTa-I-._~.VlOD~_._ 64 August 14, 1998

indicated that results of a combustion risk assessment would be shared with the public prior toimplementing any thermal treatment operations associated with this ROD.

Iowa Anny Ammunition PlantSolis OU#1, Record of Decision (Revision No.1)Ivt..11P1lO.JECTS-ll5NC_IftIN4J.VlClOl5l44/a-...... 6S August 14, 1998