95
RISK-BASED CONCENTRATION REPORT FURNACE GROUP ALCOA - DAVENPORT WORKS CERCLA Consent Order VII-95-F-0026 foit* AL£Q ft "N ID mxtYrffQ^oKrtQ Braak & Q Ofchar- 5 *7<$y x^ C-jpjr>^\ J 40166169 SUPERFUND RECORDS NPDES Outfall 006 Prepared by IT Corporation 2790 Mosside Boulevard Monroeville PA 15146-2792 Prepared by IT Corporation 2790 Mosside Blvd Monroeville PA 15146 December 2001 Revised by MFC, INC consulting scientists and engineers 800 Vmial Street Pittsburgh PA 15212 (412)321 2278 FAX (412)321 2283 May 2004 MFG Project No 120337

RISK-BASED CONCENTRATION REPORT

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RISK-BASED CONCENTRATION REPORTFURNACE GROUP

ALCOA - DAVENPORT WORKSCERCLA Consent Order VII-95-F-0026

foit* AL£Q ft "NID mxtYrffQ^oKrtQBraak & QOfchar-

5 *7 <$yx^ C-jpjr>^\ J

40166169

SUPERFUND RECORDS

NPDESOutfall 006

Prepared by

IT Corporation2790 Mosside BoulevardMonroeville PA 15146-2792

Prepared by

IT Corporation2790 Mosside Blvd

Monroeville PA 15146

December 2001

Revised by

MFC, INCconsulting scientists and engineers

800 Vmial StreetPittsburgh PA 15212

(412)321 2278FAX (412)321 2283

May 2004

MFG Project No 120337

Alcoa Mill Products

4879 State StreetALCOA po Box 1047

Bettendorf IA 52722 1047 USATel 1 319 459 2000 *-

January? 2002Mr Jim ColbertU S Environmental Protection AgencyRegion VII501 N S t h s tKansas City Kansas66101

Subject Final RBC Report for *he Furnace Group, Alcoa Davenport WorksCERCLA Consent Ordei V1I-95-F 0026

Deai Jin

Enclosed are three copies of the Final Risk Based Concentration (RBC) Report <or the Furnace GroupTr>A Units IPO 04 IPO 05 IPO 08 and IPH 09 Revisions were based on discussions between Alcoa"nd EPA and EPA comments on various RBC reports including Outfall 001 Sewer Group Bone YardGroup Former Li^ht Bulb Dump EHDS & WDS Unit Gioup and Foil Mil l Unit Croup

If you need udditioiai information or have questions about the enclosed information do no* hesitate tocontact me at (563) 459 1629

Yours T uly

Bud SturtzerDavenport Remediation

Cc George Pratt

870361 224 A

FV

RISK-BASED CONCENTRATION REPORTFURNACE UNIT GROUP

ALCOA-DAVENPORT WORKS

Prepared for

Aluminum Company of AmericaRiverdale, Iowa

Prepared by

IT Corporation2790 Mosside Blvd

Monroeville, PA 15146

December 2001

Revised by

MFC, INCconsulting scientists and engineers

800 Vmial StreetPittsburgh PA 15212

(412)321 2278FAX (412)321 2283

May 2004

MFG Project No 120337

RECEIVED

MMT imSUPERFUND DIVISION

TABLE OF CONTENTS

Section Page

1 0 INTRODUCTION 1 11 1 OBJECTIVES 1 2

1 1 1 Unit Conceptual Model (Task 4 of Overview Strategy) 1 21 1 2 Exposure Assessment (Task 5 of Overview Strategy) 1 31 1 3 Risk Based Concentrations (Task 6 of Overview Strategy) 1 3

1 2 ORGANIZATION 1 41 3 UNIT GROUPING 1 5

2 0 UNIT CONCEPTUAL MODEL 2 12 1 UNIT GROUP DESCRIPTION 2 1

2 1 1 50 Inch Continuous Heat Treat Line (IPO 04) 2 12 1 1 1 Unit Description 2 I2 1 1 2 Data Usability 2-4

2 1 2 Ingot Plant Melting Furnaces and Casting Pits (IPO 05) 2 52 1 2 1 Unit Description 2 52 1 2 2 Unit Data 2 72 1 2 3 Data Usability 28

2 1 3 Soaking Pits (IPO 08) 2 92 1 3 1 Unit Description 2 92 1 3 2 Unit Data 2 92 1 3 3 Data Usability 210

2 1 4 No 8 and No 9 Vertical Heat Treatment Furnaces (IPH 09) 2102 1 4 1 Unit Description 2102 1 4 2 UmtData 2112 1 4 3 Data Usability 211

2 1 5 Proximity and Relationship to Surrounding Units 2 112 2 DATA REVIEW 2 12

2 2 1 Data Validation 212222 Data Compilation and Review 2 13

2 2 2 1 Data Selection and Evaluation 2 132 2 2 2 Evaluation of Duplicate Samples 2 13

2 3 INTRODUCTION TO UNIT GROUP RISK AND EXPOSUREPOTENTIAL 2 142 3 1 Selection of Constituents of Interest 2 14232 Selection of Constituents of Potential Concern 2 15233 Constituent Characterization 2 16

2 3 3 1 Physical and Chemical Properties 2 162 3 3 2 Toxicity Values 2 18

2 4 RELEASE MECHANISMS MIGRATION PATHWAYS ANDEXPOSURE PATHWAYS 2 192 4 1 Primary Release Mechanisms 2 19242 Potential Secondary Release Mechanisms and Migration Pathways 2 20243 Potential Human and Ecological Exposure Pathways 2 20

Furnace Unit Group RBC ReportRev Fum Grp pc2 i Rev May 2004

TABLE OF CONTENTS(Continued)

3 0 EXPOSURE ASSESSMENT 3 13 1 EXPOSURE SCENARIOS 3 13 2 EXPOSURE POINT CONCENTRATIONS 3 1

4 0 RBC CALCULATIONS AND COMPARISONS 4 14 1 CURRENT AND FUTURE RECEPTORS 4 14 2 POTENTIAL FUTURE RECEPTORS 4 24 3 UNCERTAINTY ANALYSIS 4 2

5 0 CONCLUSIONS 5 1

6 0 REFERENCES 6 1

List of Figures

.F/gwre

1-1 Location and Physical Setting of Alcoa Davenport Works Riverdale Iowa

2 1 Location of the Furnace Group and Surrounding FSA Units

2-2 Location of Soil Samples at the Furnace Group

2 3 Unit Conceptual Model for Potential Exposure at the Furnace Group

List of Tables

Table

2-1 Review of Data Useabihty Criteria for Risk Assessment

2-2 Soil Samples Included in Risk Calculations

2 3 Identification of COIs and COPCs for Subsurface Soil

2-4 Physical and Chemical Properties of Constituents of Potential Concern

2 5 Toxicity Criteria for Constituents of Potential Concern

3 1 Exposure Assumptions

3 2 Exposure Point Concentrations for COPCs in Subsurface Soil

Furnace Unit Group RBC ReportRev Furn Grp pc2 u Rev May 2004

TABLE OF CONTENTS(Continued)

List of Tables (Continued)

Table

4 1 Risk Based Concentration Calculation Equations for Subsurface Soil Exposure

4 2 Risk Based Concentrations for Excavation Repair Worker Exposure to Subsurface Soil

4 3 Risk Based Concentrations for Excavation Construction Worker Exposure to Subsurface Soil

4 4 Comparison of Exposure Point Concentrations to Risk Based Concentrations ExcavationRepair Worker Exposure to Subsurface Soil

4 5 Comparison of Exposure Point Concentrations to Risk Based Concentrations ExcavationConstruction Worker Exposure to Subsurface Soil

4 6 Comparison of Exposure Point Concentrations to Risk Based Concentrations Frequent OnSite Worker Scenario

4 7 Comparison of Exposure Point Concentrations to Risk Based Concentrations OccasionalOn Site Worker Scenario

4 8 Comparison of Exposure Point Concentrations to Risk Based Concentrations Infrequent OnSite Worker Scenario

List of Appendices

Appendix A Analytical Data

Appendix B Unit Recommendation Memo Furnace Group

Furnace Unit Group RBC ReportRev Fum Grp pc2 in Rev May 2004

LIST OF ACRONYMS

AA

Alcoa

AOC

ARAR

atm m /mol

bgs

CERCLA

CHT

cm

COIs

COPC

Csat

CSF

CSM

CWM

ECAO

ELCRs

EPA

EPC

Exposure Menu

ft

foe

FSA

FSD

g/mol

H

HEAST

HI

HQ

HU

IDNR

ICP

Atomic Absorption

Aluminum Company of America

Administrative Order on Consent

Applicable or Relevant and Appropriate Requirements

Atmosphere Cubic Meter per Mole

Below ground surface

Comprehensive Environmental Response Compensation and

Liability Act

Continuous Heat Treatment

Square Centimeter

Constituents of Interest

Constituent of Potential Concern

Soil Saturation Limit

Cancer Slope Factor

Conceptual Site Model

Current Waste Management Unit

Environmental Criteria and Assessment Office

Excess Lifetime Cancer Risks

United States Environmental Protection Agency

Exposure Point Concentration

Menu of Facility Specific Exposure Scenarios

FeetFraction of Organic Carbon

Facility Site Assessment

Facility Services Department

Grams per Mole

Henry s Law Constant

Health Effects Assessment Summary Tables

Hazard Index

Hazard Quotient

Historical Unit Area

Iowa Department of Natural Resources

Inductively Coupled Plasma

870361 233 AQ IV

Furnace Unit Group RBC ReportDecember 2001

LIST OF ACRONYMS - CONTINUED

IFF

IPH

IPO

IRIS

IWT

Kd

kg

KOCKOWmg/cm^

mg/day

mg/kg

mg/kg day

mg/L

mL/g

mm Hg

MRP 15

m /day

m3/hr

m3/kg

NET

ND

NPDES

Overview Strategy

PCBs

PRGs

PW

QA/QC

QAPP

RBCs

RfCs

RfD

RI

SQLs

Foil Mill Area

Hot Rolling Mill Area

Other Process Area

EPA Integrated Risk Information System

Incineration Waste Treatment

Partition Coefficient

Kilogram

Organic Carbon Partition Coefficient Values

Octanol/Water Partition Coefficient

Milligrams per Square Centimeter

Milligrams per Day

Milligrams per Kilogram

Milligrams per Kilogram Day

Milligrams per Liter

Milliliters per Gram

Millimeters of Mercury

Mississippi River Pool 15

Cubic Meters per Day

Cubic Meters per Hour

Cubic Meters per Kilogram

National Environmental Testing

Non detect

National Pollution Discharge Elimination System

Overview of Cleanup Strategy

Polychlonnated Biphenyls

Preliminary Remediation Goals

Pumping Well

Quality Assurance and Quality Control

Quality Assurance Program Plan

Risk Based Concentrations

Reference Concentrations

Reference Dose

Remedial Investigation

Sample Quantitation Limits

870361 233 AQFurnace Unit Group RBC Report

December 2001

LIST OF ACRONYMS - CONTINUED

svocTCR

THI

TPH

UCL

UCM

Unit Group

URM

VOCs

VFX

Semi Volatile Organic Compound

Target Cancer Risk

Target Hazard Index

Total Petroleum Hydrocarbons

Upper Confidence Limit

Unit Conceptual Model

Furnace Group

Unit Recommendation Memorandum

Volatile Organic Compounds

Vertical Heat Treatment Furnace

870361 233 AQ VI

Furnace Unit Group RBC ReportDecember 2001

10 INTRODUCTION

In August 1995 Aluminum Company of America (Alcoa) and United States Environmental

Protection Agency (EPA) signed an Administrative Order on Consent (AOC) Docket No VII 95 F

0026 that provides for the evaluation of and if necessary the performance of removal actions for

the areas of potential contamination at the Alcoa Davenport Works in Riverdale Iowa (Figure 1 1)

Eighty one areas of potential contamination or units were identified in a 1992 Initial Facility Site

Assessment Report (FSA [Geraghty & Miller Inc 1992]) Included in the list were FSA Units IPO

04 (50 Inch Continuous Heat Treatment Line {Former Paint Line location}) IPO 05 (Ingot Plant

Melting Furnaces and Casting Pits) IPO 08 (Soaking Pits) and IPH 09 (No 8 and No 9 Vertical

Heat Treatment Furnaces) Prior to development of this report Units IPO 04 IPO 05 IPO 08 and

IPH 09 were grouped as similar units to be addressed in this Furnace Group RBC Report Alcoa

received EPA approval for this unit group in correspondence dated May 29 1998 Rationale for

grouping these units is presented in Section 1 3

This RBC report was prepared in accordance with the Overview of Cleanup Strategy (Overview

Strategy) document presented as Appendix B of the 1995 AOC (EPA 1995a) The Overview

Strategy outlines a series of tasks to be completed as part of a comprehensive risk based strategy for

unit characterization and pnontization

Task 1 of the Overview Strategy involved preparation of a formal site wide Conceptual Site Model

(CSM) (Geraghty & Miller Inc 1995a) to provide a general understanding of the relationship

between the units and site characteristics The site wide CSM submitted to the EPA on October 13

1995 identifies site characteristics potential sources of constituents at FSA units constituents of

interest (COIs) primary and secondary constituent release mechanisms and conditions impacting

constituent migration Task 2 of the Overview Strategy was EPA review and approval of the CSM

The CSM was approved by EPA on November 22 1995

Task 3 consisted of an Applicable or Relevant and Appropriate Requirements (ARAR) review by

EPA and other appropriate agencies This review is covered in the EPA document Chemical and

Location Specific ARARs Analysis Report for the Alcoa Davenport Works Site Riverdale Iowa

transmitted December 22 1995 Task 4 involves development of a Unit Conceptual Model (UCM)

for each FSA unit or group of units Task 5 is an Exposure Assessment for each applicable receptor

chosen from the Menu of Facility Specific Exposure Scenarios (Exposure Menu) for each unit

Furnace Unit Group RBC Report870361 233 AQ 1 1 December 2001

Task 6 involves the calculation of Alcoa specific RBCs for each identified constituent of potential

concern (COPC) The approved CSM served as the foundation for completing Tasks 4 through 6 of

the Overview Strategy Following completion of Task 6 RBCs were compared to unit analytical

data and this RBC Report was prepared for submittal to EPA for review and approval

EPA developed a supplemental document in the 1995 AOC titled Preliminary Methodology for

Tasks 4 5 and 6 of the Overview of Cleanup Strategy (Tasks 4 5 and 6 Document [EPA 1995a])

This document presents a general framework for completion of Tasks 4 5 and 6 (outlined above) of

the Overview Strategy Attachment 1 to the Tasks 4 5 and 6 Document provides an example of the

application of Tasks 4 5 and 6 to specific FSA units but is not necessarily a rigid format

Application of the Overview Strategy to units and groups of units will vary depending on the

characteristics of the unit and the extent to which the unit has been previously investigated

This RBC Report includes the UCM Exposure Assessment and calculation of Alcoa specific RBCs

for COPCs identified at the Unit Group and the Unit Recommendation Memorandum (URM) Each

of these tasks was completed in accordance with the Overview Strategy and the Tasks 4 5 and 6

Document

The objectives of each task necessary to complete the RBC Report are discussed m the following

sections

1 1 OBJECTIVES

Completion of Tasks 4 5 and 6 of the Overview Strategy is necessary for initial evaluation of the

Unit Group area and to calculate RBCs for COPCs based on application of Alcoa specific exposure

scenarios RBCs will be used in screening to determine whether the unit requires additional action as

the result of evaluation under the Consent Order (VII 95 F 0026) Additional action may consist of

continued evaluation (i e application of unit specific exposure parameter values to calculate unit

RBCs for COPCs field investigation or other investigation) or a removal action Major objectives

of Tasks 4 5 and 6 in this overall site strategy are outlined below

111 Unit Conceptual Model (Task 4 of Overview Strategy)

The UCM was developed based on the Initial FSA and the formalized site wide CSM The major

objective of the UCM is to identify unit characteristics and conditions impacting constituent

migration exposure pathways and receptors (human and ecological) A summary of unit COIs is

Furnace Unit Group RBC Report870361 233 AQ 1 2 December 2001

provided based on a review of available analytical data and process knowledge COPCs are then

developed from the list of COIs

112 Exposure Assessment (Task 5 of Overview Strategy)

The major objective of the Exposure Assessment is to assess potential for exposure of human and/or

ecological receptors to environmental media at the unit Alcoa specific site wide human exposure

scenarios for soil surface water sediment and groundwater were developed and submitted to EPA

for approval in a document entitled Menu of Facility Specific Exposure Scenarios for Soil Surface

Water Sediment and Groundwater Alcoa Davenport Works (Exposure Menu) (Geraghty & Miller

Inc 1995b) The Exposure Menu was approved by the EPA and included in the 1995 AOC Human

exposure scenarios applicable to the Unit Group were selected from the Exposure Menu and used to

calculate RBCs Human exposure scenarios acknowledge current and anticipated future industrial

use of Alcoa Davenport Works The scenarios also acknowledge limited access to Alcoa Davenport

Works by the public

The potential for direct exposure of ecological receptors to environmental media at the Unit Group

was also evaluated As outlined in the 1995 AOC the first step in the ecological evaluation of an

FSA unit involves the identification of ecological habitat If no ecological habitat is identified at an

FSA unit no further ecological evaluation is conducted If applicable habitat is identified the

analysis proceeds with the second step of the ecological evaluation process in a manner consistent

with the screening approach outlined for human health evaluation No ecological habitat has been

identified at this Unit Group

113 Risk-Based Concentrations (Task 6 of Overview Strategy)

RBCs for identified media specific COPCs are calculated based on site wide exposure scenarios

specific to the Alcoa Davenport Works selected from the Exposure Menu RBCs are calculated for

Total Cancer risk (TCR) at 1 x 10 4 and 1 x 10 6 for cancer effects and a Target Hazard Index (THI)

of 1 for non carcinogenic effects These RBCs are compared with exposure point concentrations

(EPCs) in environmental media at the Unit Group The data are reviewed to determine if a sufficient

amount of data are available to perform statistical evaluations If there are an insufficient number of

data points to perform statistical evaluations the EPC defaults to the maximum detected

concentration or the range of non detects If the data set is adequate for statistical evaluation the

percentage of non detects is determined and the EPC is calculated as the 95 percent upper confidence

Furnace Unit Group RBC Report870361 233 AQ 1 3 December 2001

limit (UCL) 90th and 95th percentiles or range of detection limits per the amendment to the 1995

AOC

12 ORGANIZATION

This RBC report was developed in a manner consistent with the general format provided in

Attachment 1 of the Tasks 4 5 and 6 document and includes the following components

• Unit Conceptual Model

• Exposure Assessment

• RBC Calculations and

• Comparison of RBCs to EPCs

Section 2 0 provides a description of the Unit Group in terms of proximity to property boundary and

surrounding units summary of previous investigations quantity and quality of available analytical

data (Appendix A) and identification of COIs and COPCs The UCM also discusses the

physical/chemical and lexicological properties of the COPCs identifies primary and secondary

constituent release mechanisms and migration pathways and discusses potential exposure pathways

for human receptors

Section 3 0 provides a discussion of exposure pathways and parameters from the Exposure Menu that

were used to calculate Alcoa specific RBCs for comparison to unit constituent concentrations EPCs

are also identified in this section

Section 4 0 discusses the methodology used to calculate RBCs for each applicable medium receptor

and exposure pathway Equations and exposure parameters used to assess oral dermal and

inhalation exposure to COPCs are presented and example calculations are provided in table format

EPCs identified in Section 3 0 are compared to calculated RBCs This comparison will serve as the

basis for recommendations provided in the URM The URM is included as Appendix B of this

report

Section 5 0 provides conclusions based on the results of the risk assessment

Furnace Unit Group RBC Report870361 233 AQ 1 4 December 2001

1 3 UNIT GROUPING

The Furnace Group was formed because each unit in the group is located in the central area of the

mam plant structure and each unit uses heat as part of the industrial process Also each unit consists

of heavy machinery or furnaces in buildings where there is no routine access to subsurface soil

Therefore similar exposure scenarios are appropriate at each unit in the grouping The appropriate

receptors selected for evaluation at this Unit Group are the excavation repair worker and the

excavation construction worker Similar environmental conditions also exist at these units because

the ground surface is either paved or consists of a concrete floor covered in wood floor block Each

unit in the group is located in the central part of the facility

Furnace Unit Group RBC Report870361 233 AQ 1 5 December 2001

2 0 UNIT CONCEPTUAL MODEL

The Alcoa Davenport Works plant is located in Riverdale Scott County in east-central Iowa

adjacent to Bettendorf Iowa, one of the Iowa Illinois Quad Cities (Figure 1 1) The site is bounded

to the south by the Mississippi River, to the north by State Route 67, to the east by the Riverside

Power Plant and by residential industrial and undeveloped property to the west A more complete

site description is presented in the site wide CSM (Geraghty & Miller, 1995a)

2 1 UNIT GROUP DESCRIPTION

FSA Units included in the Furnace Unit Group are all located within buildings in the central part of

the plant Figure 2 1 identifies units within this Unit Group and the location of surrounding FSA

Units This section provides a brief overview of each FSA Unit included in this Unit Group

Figure 2 2 illustrates the location of soil samples collected within the Furnace Group and soil

analytical results are presented in Appendix A In addition Appendix A presents a summary of

analytical results for samples of hydraulic oil and gearbox oil collected under a program to identify

and eliminate PCBs in hydraulic systems and other equipment at the Davenport Works For more

details the reader is referred to the April 15 1992 Initial Facility Site Assessment Report and the

October 13 1995 Conceptual Site Model

211 SO-lnch Continuous Heat Treat Line OPO-04)

The 50 Inch CHT Line is within Building 825 between rows L and M and columns 87 and 109 It

was installed in 1979 and is still in operation The 50 Inch CHT Line was installed during the time

period that Davenport was phasing out the use of PCB containing substances A paint line operated

in this area from 1960 until the time the Continuous Heat Treatment (CHT) line was installed

2 1 1 1 Unit Description

Coils of aluminum are brought to the unwind pit of the 50 Inch CHT Line from prerequisite

operations such as cold rolling The aluminum coils are transferred to equipment in the unwind pit

and the aluminum is threaded into the CHT Line The aluminum sheet is unwound and goes through

a pinch roller flattener and trimmer at the beginning of the operation where the sheet is flattened and

irregular edges of the sheet are removed The uncoiled sheet is then pulled through the furnace

section to be heat treated Following heating in the furnace the metal is water quenched to set the

Furnace Unit Group RBC ReportRev Fum Grp pc2 2 1 Rev May 2004

metallurgical properties The sheet is then recoiled and removed from the line as feed stock for other

plant operations or for direct sale

Water from the quench operation is now recycled within the operation however prior to January

1997 water was discharged to Outfall 003 Currently excess overflow is discharged to the storm

sewer system and pumped to lift station 003 and subsequently to the Water Reclamation Facility

(FSA Unit CWM 12) for treatment and recycle in the plant water system Untreated quench water is

occasionally discharged to the Mississippi River via Outfall 003 during extreme storm events when

the lift station overflows

At the 50 Inch CHT Line excess hydraulic oil accumulates in the hydraulic pits and is periodically

collected with a vacuum truck for disposal at the Industrial Waste Treatment (IWT) Facility (FSA

Unit CWM 10) As with all equipment in the plant equipment associated with this unit no longer

uses fluids containing PCBs however some systems may have contained low levels PCBs in the past

and may still contain residual PCBs at levels below regulatory concern Hydraulic systems and

gearboxes associated with equipment at this unit group have been tested to determine if residual

PCBs are present under guidelines in the Davenport Works PCB Management Plan (Alcoa, 1998)

Prior to installation of the 50 Inch CHT Line in 1979 the area was occupied by a coiled aluminum

paint line The paint line was installed around 1960 and was removed in 1979 when the 50 Inch

CHT was installed The paint line included a coater house where paints solvents and other coatings

were mixed and prepared for use Aluminum sheet was transferred to the paint line as coiled stock

from cold rolling operations At the paint line the aluminum was uncoiled as it was pulled through

rollers to apply the paint and then pulled through a drying oven The paint line was installed entirely

within a covered building with concrete floors so it is unlikely that materials reached soil or

groundwater beneath the unit

A release occurred at the 50 Inch CHT line on June 11 1991 when the stem of a relief valve blew off

the hydraulic unit The hydraulic unit contained approximately 160 gallons of phosphate ester

(ML 924) Spill reports indicate that clean up was conducted using oil dry pads and pigs around the

area to keep phosphate ester from running out the man door and around the storm sewer The leaked

phosphate ester and clean up material was disposed by the Facility Services Department (FSD)

Because the spill occurred inside the building there was no release to soil

Furnace Unit Group RBC ReportRev Furn Grp pc2 2 2 Rev May 2004

2 1 1 1 1 Unit Data

In September 1991 Geraghty & Miller conducted an investigation in conjunction with excavation

work performed by Castle Construction for the VFX Furnace area Samples were collected to assess

if PCBs and VOCs were present beneath the furnace foundation prior to excavation for construction

activities The data were used to determine the proper disposal of the excavated soils in accordance

with state and federal regulations The subsurface investigation included collection of three soil

samples from locations beneath the proposed excavation area Samples with the highest VOC and

PCS field screening results were selected for laboratory analysis Two soil samples B-l and B 2

were analyzed by Belmg Consultants for PCBs (SW846 8080) and sample B 2 was analyzed for

VOCs (SW846 8240) A third sample was not submitted for chemical analysis due to the absence of

a Geraghty & Miller representative during the collection of the sample Sample B 1 was collected

from 7 to 8 5 ft bgs and sample B 2 from 3 to 5 ft bgs Analytical results for B 1 indicated one

detection of Aroclor 1248 at 025 mg/kg Analytical results for B 2 indicated methyl ethyl ketone

(MEK) was detected at 0 28 mg/kg and Aroclor 1248 was detected at 0 25 mg/kg

A second phase of field work in September 1991 tested near surface composite samples from several

locations beneath the floor for the presence of VOCs and PCBs These soil samples were collected

from 3 to 5 feet bgs and were analyzed by Wadsworth Alert Laboratory for VOCs (SW846 8240) and

PCBs (SW846 8080) Samples were collected under a biased sampling strategy with the highest

VOC and PCB field screening results selected for laboratory analysis Sample VMX-1S represents a

composite of soils located around the southeast pillar of the excavation area, VMX 2S in the

northwest corner and VMX 3S at the eastern wall of the excavation Analytical results for VMX IS

VMX 2S and VMX-3S indicated low levels of acetone MEK and trichloroethene (TCE) were

detected in each sample In addition, 2 hexanone methylene chloride, tetrachloroethene (PCE),

toluene and 1 methyl 4 cyclohexane (a tentatively identified compound) were detected at estimated

concentrations below the reporting limit PCBs were not detected Results from soil samples

collected at the unit are presented m Table A 1 (Appendix A) Soil samples were collected to

determine appropriate requirements for disposal of soil from the construction project

Approximately 1 200 cubic yards of soil were excavated during the construction project and

stockpiled in a containment cell onsite while laboratory analysis was completed

As with all equipment in the plant equipment at this unit group no longer uses fluids containing

PCBs, but some systems may have contained low levels in the past and may still contain residual

Furnace Unit Group RBC ReportRev Fum Grp pc2 2 3 Rev May 2004

PCBs Davenport Works maintains a comprehensive program to identify and eliminate sources of

residual PCBs in equipment and machinery Hydraulic fluids and gearbox oil have been tested to

determine if residual PCBs are present Where PCBs are detected specific actions are initiated

based on guidelines in the Davenport Works PCB Management Plan If PCBs are detected at

concentrations greater than 50 parts per million (ppm) the equipment is decontaminated within 1

week refilled and retested after 3 months For equipment where PCBs are detected at concentrations

between 49 ppm and 30 ppm the equipment is decontaminated within 3 months refilled, and retested

after 3 months Any fluids removed from equipment with PCB concentrations greater than or equal to

30 ppm is disposed off site by incineration For equipment with concentrations between 29 ppm and

2 ppm fluids are drained and refilled as part of normal maintenance activities Fluids recovered

from maintenance activities are transferred to the Industrial Waste Treatment Facility

At the 50 Inch CHT Line oil from 39 gearboxes and hydraulic units were sampled for PCBs and

detected values were reported from two hydraulic units One detected value of 11 mg/kg Aroclor

1260 is from sample SF 50EN HY06 of hydraulic system oil in the exit accumulator at the 50 Inch

Line collected on October 2 1986 A sample from the same system in 1991 was below detection

The second system with a detected value was in sample SF 50IN HY09 collected on September 30

1990 from the steering roll hydraulic system Aroclor 1248 was detected at 2 7 mg/kg in sample SF

50IN HY09 All other results from the testing program were below detection A summary of results

from the gearbox and hydraulic system testing program are presented in Appendix A (Table A 2)

2 1 1 2 Data Usability

Analytical data from soil samples collected at this unit the 50 CHT Line are appropriate for use in

risk calculations except for the VOC data from VMX IS through VMX 3S because these samples

were composites and the results (all non detect or detected below PRO) may be biased low Note the

PCB data for samples VMX IS through VMX 3S (non detect SQLs) were used in the risk

calculations Documentation for samples VMX IS to VMX 3S and B 1 and B 2 is limited however

the sampling results are believed to be representative of soil below the floor in this area

Documentation available for VMX IS VMX 2S VMX 3S B 1 and B 2 includes the Report of

Findings, Soil Sampling Investigation at the VFX Furnace Excavation written by Geraghty & Miller

(199la) Tables of the results and depths, and figures of the locations were included in the report

Although limited documentation is available the soil samples are representative of conditions that

would be encountered during a repair or construction project

Furnace Unit Group RBC ReportRev Fum Grp pc2 2 4 Rev May 2004

Data from hydraulic systems and gearbox oil were not used in risk calculations but were considered

qualitatively to support the evaluation of the unit The data were not used in calculations since

hydraulic fluid and gearbox oil are not environmental media however the data provide information

about potential sources of residual PCBs Results of this program are documented in a database

maintained by the Davenport EHS but some aspects of the sampling program are not contained in

the database The exact location of each hydraulic system or gearbox m relation to the unit field

sampling protocol analytical methods and detection limits are not identified in the database A

summary of results from the hydraulic system and gearbox testing are presented in Table A 2

212 Ingot Plant Melting Furnaces and Casting Pits (IPO-05)

IPO 05 is located at the south and east ends of Building 810 The unit historically and currently

consists of aluminum melting furnaces and casting pits where aluminum and alloying materials are

melted and cast into ingots for use in hot rolling operations This entire unit is under roof and the

ground surface is concrete floor

2 1 2 1 Unit Description

Aluminum and alloying materials are placed in the melting furnaces and heated until the metal

reaches a molten state The molten aluminum is then transferred to a holding furnace where chlorine

and nitrogen gas is bubbled through the molten metal to remove impurities (called fluxing)

Impurities rise to the surface of the bath and are skimmed off for disposal Historically this skim (or

dross) was disposed in the Former Waste Disposal Site (HU 09) Eastern Historical Disposal Site

(HU 11) and the Western Disposal Site (CWM 13) Currently the skim is sent off site to a

reclamation center The molten metal is then passed through molten metal filters for further removal

of impurities and is cast into ingots The ingot is formed when the molten metal is poured into a mold

and is water cooled to accelerate solidification Lubricating oil is used in the mold and this oil is

discharged with the cooling water Historically the contact cooling water along with the lubricating

oil was discharged to the Mississippi River via NPDES Outfall 006 Currently the cooling water is

captured within the plant water recycle system Historically, castor oil was used as the lubricating

oil Currently a product identified as XL 1081 (stock number 051 9752081 MSDS number

104916) is used to lubricate the molds

Cooling water may periodically become contaminated with hydraulic oils that historically contained

low levels of PCBs However results of the program to test hydraulic systems indicate that out of

Furnace Unit Group RBC ReportRev Fum Grp pc2 2 5 Rev May 2004

more than 900 samples PCBs were detected in only three hydraulic units and one gearbox

Currently all water from this operation is collected treated and reclaimed within the plant Drains

in casting pits at the unit are connected to the storm sewer system that discharges to the ingot sump

adjacent to the Outfall 006 lift station The ingot sump pumps this water to the Ingot Water Recycle

System where it is treated prior to reuse

The Ingot Plant Melting Furnaces and Casting Pits (IPO 05) became operational m 1948 and the area

remains an ingot plant today However over the years the original furnaces and casting pits have

been replaced with larger more modern equipment Each melting furnace is approximately 30 ft by

20 ft Casting pits vary in depth from approximately 35 ft to 50 ft In addition, as with all equipment

in the plant equipment associated with this unit no longer uses any fluids containing PCBs

On December 3 1981 Alcoa was issued an Approval to dispose of an estimated 2 5 million gallons"Ike c> /

of PCB containing reclaimed fuel oil in the No 14 reverberatory melting furnace that was stored in

the east and west one million gallon storage tanks To verify high destruction efficiency the

Approval contained a set of Conditions based upon information obtained during a test burn (e g

requirements that the furnace temperature be maintained at greater than 1100°C [2012°F] and stack

gas concentrations of less than 50 ppm carbon monoxide and greater than 3% excess oxygen) and

authorization was granted pursuant to Section 6(e) of the Toxic Substances Control Act (TSCA) and

40 CFR 761 10 Also a January 26 1983 Alcoa letter to EPA Region 7 provided written notice of an

additional 200 000 to 300 000 gallons of PCB containing oil that was to be removed from a storage

lagoon in Atkinson Illinois (pursuant to an EPA Region V Consent Decree) and transported and

stored in the fuel oil tanks at the Alcoa Davenport facility for ultimate disposal in the No 14 furnace

The January 26 1983 letter indicated that 1 6 million gallons of fuel oil were stored in the 2 one

million gallon tanks at that time An EPA Region VII Consent Decree and Final Order (TSCA

Docket No VU 87 T 0027) indicates that Alcoa settled all PCB violations through October 1 1988

and also required Alcoa to complete the disposal of all PCB contaminated oil in an on site storage

tank (referred to as Tank No 2) with subsequent decontamination of the tank Therefore on

November 18, 1988 Alcoa was granted Revised Approval to continue burning in the No 14 furnace

the remainder of the PCB containing fuel oil (approximately 800 000 gallons in the west storage

tank) identified m the onginal Alcoa application However to assure compliance with schedule

requirements PCB containing oil was also incinerated at off site facilities after being removed from

the east and west tanks in 1989 and 1990 respectively Sludge was also removed and the tanks were

Furnace Unit Group RBC ReportRev Furn Grp pc2 2 6 Rev May 2004

decontaminated A letter dated April 19 1991 from EPA confirms that Alcoa achieved the PCB

cleanup in accordance with the requirements of the TSCA Consent Decree (Docket No VII 87 T

0027)

During the late 1980s in parallel with the work performed under the TSCA Consent Decree (Docket

No VII 87 T-0027) Alcoa made arrangements for the construction and operation of an oil

reclamation facility (formerly the PORI facility and currently owned and operated by US Filter) The

oil reclamation process mechanically and chemically filters and concentrates oil from various oily

waste sources throughout the Alcoa Davenport facility to produce fuel quality oil that is

subsequently burned in the melting furnaces The recycled oily waste contained quantifiable levels of

PCBs and therefore in a November 15 1988 letter to EPA Region VII, Alcoa filed a notification of

Used Oil Burning Activities to request authorization to burn the oil in the melting furnaces at the

Alcoa Davenport facility EPA's February 21 1989 response letter cited the PCB Exclusions

Exemptions and Use Authorization Rule as authorization to burn PCB oil with concentrations of less

than 50 ppm PCBs provided the melting furnaces met the requirements of 40 CFR 260 10 and 40

CFR 266 41 (b) In a May 26 1993 letter to EPA Region VII Alcoa filed the required renotification

of Used Oil Processing and Burning Activities and Alcoa continues to file Used Oil Processing

Reports with EPA Region VII on a biennial basis pursuant to 40 CFR Part 279 Standards for the

Management of Used Oil Currently, tile melting furnaces operate primarily on natural gas However,

two furnaces the No 14 and No 16 Melters, burn waste oil reclaimed from the Industrial Waste

Treatment System with No 16 operating more frequently than No 14

Spill reports summarize all major/reportable releases from the Ingot Furnaces (as defined by 40 CFR

110 Discharge of Oil) since 1986 when formal documentation of releases began A summary of spill

reports for the Ingot Plant Furnaces is presented in Appendix A (Table A 3) The reviewed

documentation does not indicate that a discharge of oil occurred from 1986 to September 13 1991

Information from the spill reports documented in Appendix A indicate that less than 80 gallons of oil

was released during various spills from furnace and casting operations since 1986 The spill reports

summarize actions taken to clean up the spills and any actions taken to prevent a reoccurrence

2 1 2 2 Unit Data

Three soil samples were collected on November 18 1998 at the Ingot Plant Melting Furnaces and

Casting Pits (IPO 05) Samples 810HA01 810HA02, and 810HA03 were collected using a hand

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auger from an area where the floor had been removed for a repair project The samples were

collected from randomly selected depths Sample 810HA01 was collected from a depth of 5 to 6 feet

bgs 810HA02 was from a depth of 3 4 feet bgs and 810HA03 was collected from 2 to 16 inches bgs

The samples were collected to determine if VOCs, SVOCs, or PCBs were present in soils near the

repair project prior to excavation The samples were analyzed by National Environmental Testing

(NET) for VOCs (SW846 8260B) SVOCs (SW846 8270C) PCBs (SW846 8082) TPH/BTEX

(Iowa method OA 1) and Extractable Hydrocarbons (Iowa method OA 2) Analytical results

indicated non detect values for all constituents with the exception of Sample 810HA03 where

Aroclor 1248 was detected at a level of 0 71 mg/kg The data were used to determine appropriate

disposal requirements for the excavated soils in accordance with state and federal regulations

Under the Davenport gearbox and hydraulic system testing program over 900 samples of oil were

collected at furnaces and casting operations between 1984 and 1995 Results of the program indicate

that one hydraulic unit and one gearbox exhibited detected PCB values Oil samples from the #4

Furnace exit hydraulics were collected repeatedly under sample identification SF 4FCE HY01 PCB

concentrations have been reduced from the initial sampling on May 7 1981 where Aroclor 1248 was

detected at 42 mg/kg to 20 mg/kg Aroclor 1248 when it was sampled on March 1 1993 One

gearbox sample SF 4FCE GB02 had a detected level of Aroclor 1248 at a concentration of 11

mg/kg on March 1 1993

2 1 2.3 Data Usability

Soil data available for this unit, IPO 05 are appropriate for use in risk calculations Sampling

locations were selected based the location of the repair project and are representative of soil

conditions at the unit The samples were collected under the Davenport Digging Permit Program (see

Attachments to Appendix B) for use in determining appropriate disposal of excavated soil and are

used in the RBC report to evaluate the excavation repair worker and excavation construction worker

scenarios No soil analytical data were available for this unit prior to the investigation field activities

in November 1998

Data from hydraulic systems and gearbox oil were not used in risk calculations but were considered

qualitatively to support the evaluation of the unit The data were not used in calculations since

hydraulic fluid and gearbox oil are not environmental media however the data provide information

about potential sources of residual PCBs Results of this program are documented in a database

Furnace Unit Group RBC ReportRev Fum Grp pc2 2 8 Rev May 2004

maintained by the Davenport EHS but some aspects of the sampling program are not contained in

the database The exact location of each hydraulic system or gearbox in relation to the unit field

sampling protocol analytical methods and detection limits are not identified in the database A

summary of results from the hydraulic system and gearbox testing are presented in Table A 2

213 Soaking Pits (IPO-08)

This FSA unit is located in the eastern end of the plant in Building 811 The unit consists of furnaces

installed below grade that were used to heat aluminum ingots to the temperature required for hot

rolling Some of these furnaces were installed with the original plant construction in the mid 1940s

and others were added over the years

2 1 3 1 Unit Description

The furnaces are mounted in a large trench or pit that runs the entire length of Building 811 and is

approximately 50 ft wide The pits are separated into three groups by access aisles The trench is

approximately 15 ft deep and the top of each furnace rises approximately 7 feet above the plant

floor Historically there were 26 soaking pit furnaces where ingots were allowed to soak in high

temperature air, hence the name soaking pits None of these furnaces are currently in operation

Half of the furnaces have been removed and the associated pits has been filled in with clean fill and

covered with concrete to provide additional floor space The remaining furnaces remain idle and will

be removed when the need for space justifies the removal expense

Spill reports reviewed during development of this report indicate no reportable releases have

occurred at the unit since 1986 when formal documentation was initiated Process knowledge

indicates that no significant quantities of VOCs PCBs or SVOCs would be expected since these

substances are not part of the processes occurring at the unit The Soaking Pits are heated with

natural gas fired furnaces and ingots are placed in the unit and heated to the temperature required for

hot rolling processes

2 1 3 2 Unit Data

Soil samples were collected in September 1997 during removal and excavation of the northern

furnaces Soil samples SOK HA01 SOK HA02 SOK HA03 SOK HA04 SOK HA05, and SOK

HA06 (a duplicate of SOK HA04) were collected from random locations and depths using a hand

auger after the floor was removed The sampling was conducted to determine if VOCs SVOCs or

Furnace Unit Group RBC ReportRev Fum Grp pc2 2 9 Rev May 2004

PCBs were present in soils beneath the floor of the unit Soil sample SOK HA02 was collected from

4 to 5 ft bgs SOK HA05 from 3 to 4 ft bgs and the remaining samples were collected from the

surface to 1 ft bgs These samples were analyzed by Quanterra Laboratory for VOCs (SW846 8240)

SVOCs (SW846 8270), and PCBs (SW846 8080) Analytical results for all six samples indicated no

detected constituents with the exception of SOK HA01 which had detections of 0 0031 mg/kg for

tetrachloroethene an estimated concentration of 0 069 mg/kg for acetone and 0 098 mg/kg for

Aroclor 1248

Under Davenport gearbox and hydraulic system testing a total of 73 oil samples were collected from

the gearboxes located at 26 soaking pits in 1992 All of the results were below detection

2 1.3 3 Data Usability

The samples SOK HA01 to SOK HA06 are appropriate for use in risk calculations Documentation

for this sampling includes field logs laboratory report and results of data validation The samples

are representative of conditions beneath the floor at the Soaking Pits since they were collected from

random locations and depths that would be pertinent under an excavation scenario Data collected

under the hydraulic system and gearbox testing were not used in risk calculations however they do

indicate that PCBs are not present in equipment at the unit Data from the program were used

qualitatively to support the results of the risk evaluation

214 No 8 and No 9 Vertical Heat Treatment Furnaces fIPH-09)

This FSA unit historically located in the north central portion of the plant in the west end of

Building 909 has been removed Prior to removal the furnaces were used to heat treat aluminum

sheet to establish required metallurgical properties

2 1 4 1 Unit Description

Aluminum sheets were hung vertically on a rack and placed in the furnaces for heating to the

required temperature The sheets were then quenched with water spray to set the metallurgical

properties Quench water from this operation discharged directly to Outfall 006 (CWM 20) [and

Historical Outfall 006 (CWM 21) until 1968 or 1969] via the Storm Sewer System (CWM 07)

Historically hydraulic systems on these furnaces contained PCB contaminated oil which may have

entered the quench pit and ultimately been discharged to the Storm Sewer System, Historical Outfall

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006 NPDES Outfall 006 and ultimately MRP 15 This unit is entirely within a building and ground

surface is concrete

The Heat Treat Furnaces were installed in 1956 and were removed in 1997 The historical location

of the Vertical Heat Treat Furnaces is now occupied by an ultrasonic inspection station and a

finished goods packing line Below grade pits and foundations related to the Heat Treat Furnaces

were not removed during installation of the above equipment Below grade foundations were left in

place pits were filled with clean sand and covered with concrete Spill reports reviewed during

development of this report indicate that no reportable spills occurred at this unit since formal

documentation of spills was initiated in 1986

2 1 4 2 Unit Data

No soil data are known to exist for this unit however one sample of gearbox oil was collected in

1994 prior to removal of the Vertical Heat Treat Furnaces Results from the program to test

hydraulic systems and gearboxes were below detection In addition data are available at other

furnace operations at Davenport where similar constituents would be expected and similar processes

are carried out For example soil data from the Ingot Plant Melting Furnaces and Casting Pits

indicate no constituents were present with the exception of one sample where PCBs were detected at

a level below 1 mg/kg in soilI

2 1 4 3 Data Usability

No soil data are known to exist for this unit however results from the gearbox oil testing discussed

above were used qualitatively to support the conclusions of the risk evaluation In addition

analytical results and process knowledge from other furnace operations indicate that significant

concentrations of VOCs, PCBs and SVOCs in soils are unlikely

215 Proximity and Relationship to Surrounding Units

FSA units in this Unit Group (shown on Figure 2 1) are located by themselves in separate buildings

in the central part of the facility Except for transformer substations (HU 07) and sewer lines there

are no other FSA Units in close proximity to this Unit Group There are no known or expected

impacts to soil or groundwater beneath this Unit Group from surrounding FSA units However since

the Storm Sewer System (CWM 07) services each unit within this Unit Group contaminants

potentially discharged into the Storm Sewer System with process water could once have reached

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Historical Outfall 006 and NPDES Outfall 006 and ultimately impacted sediment in the outfalls and

MRP 15 Since start up of the water recycle system in 1997 water from the Storm Sewer System is

treated at the Water Reclamation Facility Sediments within Historical Outfall 006 NPDES Outfall

006 and the Mississippi River will be evaluated in the RBC Reports for NPDES Outfalls and m the

risk assessment for MRP 15

2 2 DATA REVIEW

Review of field and laboratory data generated at Alcoa Davenport Works since March 1991 has been

performed according to criteria specified in the Guidance for Data Usability in Risk Assessment

(EPA 1992a) and the Quality Assurance Program Plan (QAPP) for CERCLA Assessment Activities

at the Alcoa Davenport Works Plant Riverdale Iowa (Geraghty & Miller Inc 199 Ib) The QAPP

provides quality assurance and quality control (QA/QC) procedures to ensure that site data of known

and appropriate quality are obtained during sample collection and analysis processes

221 Data Validation

Laboratory procedures were performed according to protocols as outlined in the Quanterra (formerly

Wadsworth/Alert) Laboratories QAPP (Wadsworth/Alert Laboratories 1990) by procedures

specified by National Environmental Testing Inc (NET) and/or the Iowa Department of Natural

Resources (IDNR) or according to procedures at Belmg Consultants or Analysts Inc for gearbox oil

and hydraulic system testing Most soil analytical data were reviewed in accordance with the EPA s

Laboratory Data Validation Functional Guidelines for Organic and Inorganic Analysis (EPA 1988)

Analytical documentation from the hydraulic system and gearbox testing were not reviewed during

development of this report

Data validation of organic data included the examination of sample extraction and analysis holding

times method blank trip blank and equipment blank results surrogate spike recovery results

(organics) matrix spike and matrix spike duplicate results and initial and continuing calibration

data During the data validation process data qualifiers were assigned to analytical results as follows

U = Constituent was not detected

UJ = Constituent detection limit is estimated

J = Constituent value is estimated and

R or I = Constituent value is unusable

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Values or detection limits qualified as estimated ( J or UJ ) were included in risk based

calculations presented in this report Estimated data were evaluated in the same manner as non

qualified data Inclusion of estimated data in risk based calculations did not affect selection of

COPCs and/or subsequent calculations of EPC values

No analytical data qualified as unusable were included in any risk based calculations presented in

this report

222 Data Compilation and Review

The following sections discuss the data compilation and review process including an explanation of

how duplicate samples are used in nsk based calculations

2 2 2 1 Data Selection and Evaluation

Following a comprehensive evaluation of data according to ' Guidance for Data Usability in Risk

Assessment (EPA 1992a) it was determined that the results of three investigations were adequate

for evaluating risk based scenarios Table 2 1 provides a summary of the evaluation of these data

Samples were analyzed for some or all of the following parameters, VOCs PCBs and SVOCs

Table 2 2 provides a list of the sample identifications for analytical results used in risk calculations

2 2 2 2 Evaluation of Duplicate Samples

Prior to selection of COIs and COPCs, the data set was reviewed to identify duplicate samples One

duplicate sample was identified in the Unit Group data set The sample SOK HA06 was identified as

a duplicate of the sample SOK HA04 Duplicate sample numbers are recorded on the boring logs or

in field notes A sample was determined to be a duplicate of a field sample if the duplicate and field

sample were analyzed for the same constituents and if both samples were collected from the same

location at the same time Duplicate sample results were compared to field sample results and

evaluated using the following criteria to select the value used in risk based calculations

• If both results were detected values, the greater detected value was used

• If one result was a detected value and the other was a non detect the detected value was used

and

• If both results were nondetects the lower sample quantitation limit (SQL) was retained

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2 3 INTRODUCTION TO UNIT GROUP RISK AND EXPOSURE POTENTIAL

A UCM for potential exposure at the Unit Group including primary sources of contamination and

associated potential release mechanisms and migration and exposure pathways, is presented in

Figure 2 3 Based on available historical information and analytical data from the Unit Group

primary sources of leaks or spills from activities conducted within this Unit Group may have

included hydraulic systems, underground piping and leaks in cooling water containment systems

No exposure to surface soil is possible since the entire Unit Group is within buildings Exposure to

subsurface soil may occur if soils are excavated for utility line repair or construction work There is

no routine exposure to constituents in groundwater beneath the Unit Group because groundwater is

not used or encountered during normal operations

The UCM (Figure 2-3) includes the excavation repair worker and the excavation construction worker

as potential receptors for subsurface soil Justification for using these exposure scenarios is presented

in Section 3 1

Because the Furnace Group is not identified as a perimeter unit the off site resident groundwater

exposure pathway is not applicable as a potentially relevant exposure scenario It is likely that a

groundwater transport pathway exists from the unconsolidated water bearing zone (if present) to the

shallow bedrock aquifer Although the plant s current groundwater pump and treat system captures

shallow bedrock groundwater across a significant portion of the facility it is possible that

groundwater in this zone near the eastern facility boundary flows off site to the east The

Groundwater RI provides an evaluation of the potential for off site migration of groundwater A

more detailed discussion of exposure assessment is presented in Section 3 0

23 I Selection of Constituents of Interest

This section describes the process used to select COIs in subsurface soil at the Unit Group

(Table 2 3) Analytical data for surface and subsurface soil were examined and compared to

appropriate risk based benchmarks Constituents were eliminated from the list of COIs based on the

following criteria

(a) Any constituent not detected and with less than 20 percent of the SQLs exceeding the risk

based benchmarks (described below) was eliminated from the list of COIs

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(b) Constituents of low human toxicity compared to other COIs at the unit (calcium magnesium

potassium and sodium ) were eliminated from the list of COIs

(c) Those constituents not detected and with 20 percent or more of the SQLs exceeding the

benchmarks or lacking a benchmark value were compared to the list of site wide soil COIs

presented in the site wide CSM Constituents that were eliminated as site wide COIs were

also eliminated as COIs for the Unit Group if (1) the constituent was not detected in soil and

less than 20 percent of the SQLs exceeded the regulatory benchmark or, (2) the constituent

was not detected and process knowledge indicates it is unlikely that the constituent is present

at the facility

Table 2 3 presents a summary of results for constituents analyzed in subsurface soil at the Unit

Group This table presents frequency of detection range of SQLs for non detects appropriate risk

based benchmarks percent of SQLs that exceed benchmarks and the COI selection decision for each

analyzed constituent

Selection of COIs for subsurface soil was first based on constituents detected above the SQL For

constituents not detected above the SQL the SQL was compared to EPA Region IX preliminary

remediation goals (PRGs) for industrial soil (EPA 2000) Use of PRGs as a screening tool is very

conservative because the industrial soil PRG calculations assume direct contact with soil every

workday (250 days per year) for a period of 25 years

232 Selection of Constituents of Potential Concern

This section discusses selection of COPCs for subsurface soil at the Unit Group COPCs are those

constituents that are earned through RBC calculations In this screening and selection process

maximum detected constituent concentrations were compared to their respective PRGs Constituents

were eliminated as COPCs if their maximum detected concentration was below their respective PRG

value Constituents were retained as COPCs if their maximum detected concentration was greater

than their respective PRG Finally COIs whose SQLs exceeded their respective PRGs in 20 percent

or more of the samples were retained as COPCs The selection of COPCs at the Unit Group is

presented in Table 2 3 Constituents retained as COPCs in subsurface soil at the Unit Group include

nondetected benzo(a)pyrene and dibenz(a h)anthracene

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233 Constituent Characterization

This section examines the fate and transport properties and toxicity information for COPCs in

subsurface soil at the Unit Group This information is integral to exposure characterization and RBC

calculations for the constituents

2 3 3 1 Physical and Chemical Properties

Potential fate and transport of constituents in the environment is determined by characteristics of the

environmental media (e g temperature pH moisture content) and by physical and chemical

properties of the constituent Table 2 4 summarizes important physical and chemical properties for

organic COPCs at the Unit Group The table presents molecular weight water solubility specific

gravity vapor pressure Henry s Law Constant (H) diffusivity organic carbon partition coefficient

(Koc) logarithm of the octanol/water partition coefficient (log KOW) and constituent half life (Tl/2)

in soil This section defines each of these properties and the expected impact on fate and transport

potential of COPCs at this Unit Group

The molecular weight of a compound is the mass of one mole (6 022 * 10 molecules) of the

substance in grams per mole (g/mol) Smaller less complex molecules have lower molecular weights

than larger more complex molecules In general the relative mobility of a constituent is expected to

decrease with increasing molecular weight As shown in Table 2-4 molecular weights for organic

COPCs at this Unit Group range from a low of 252 g/mol for benzo(a)pyrene to a high of 278 g/mol

for dibenz(a h)anthracene

The water solubility of a substance is a primary property affecting environmental fate Highly

soluble constituents are generally mobile in groundwater and surface water Solubilities can range

from less than 1 milligram per liter (mg/L) to totally miscible with the solubility of most common

organic chemicals falling between 1 mg/L and 1 000 000 mg/L (Lyman et al 1990) The higher the

solubility the greater the tendency of a constituent to dissolve in water Table 2 4 indicates that the

solubility of benzo(a)pyrene ranges from 0 0038 to 0 004 mg/L and solubility of the

dibenz(a,h)anthracene ranges from 0 00249 mg/L to 0 005mg/L

Specific gravity of a constituent is its density relative to that of water A specific gravity greater than

1 indicates that a compound is more dense than water and a separate liquid phase of the constituent

would sink in water Similarly a specific gravity less than 1 indicates a constituent that is less dense

Furnace Unit Group RBC ReportRev Fum Grp pc2 216 Rev May 2004

than water and would float on the surface in water if present as a separate phase liquid All of the

COPCs for this Unit Group have specific gravities greater than 1 Dibenz(a h)anthracene has a

specific gravity of 1 28 and benzo(a)pyrene has a specific gravity of 1 35

Volatilization of a constituent from environmental media depends on its vapor pressure water

solubility and diffusion coefficient Highly water soluble compounds generally have low

volatilization rates from water unless they also have high vapor pressures Vapor pressure a relative

measure of the volatility of a chemical in its pure state ranges from about 0 001 to 760 millimeters of

mercury (mm Hg) for liquids and to less than 1010 mm Hg for solids Vapor pressures for the

COPCs at this Unit Group range from 5 5 E 09 mm Hg for benzo(a)pyrene to 10 0 E-10 mm Hg for

dibenz(a,h)anthracene

Henry's Law Constant combines vapor pressure with solubility and molecular weight and is

appropriate for estimating releases from water to air COPCs with Henry s Law Constants in the

range of 103 atmosphere cubic meter per mole (atm mVmol) and greater readily volatilize from

water Those with values ranging from 103 to 105 atm m3/mol (e g , most PCBs) are associated with

possibly significant but not facile volatilization Compounds with values less than 105 atm m3/mol

will only slowly volatilize from water and to a limited extent (Howard 1989 Lyman etal 1990)

Henry s Law Constants for COPCs at this unit range from a low of 7 33 E 09 atm m3/mol for

dibenz(a,h)anthracene to a high of 2 40 E 06 atm m3/mol for benzo(a)pyrene

The Kow often is used as a relative measure of the level to which a constituent will partition from

water into lipophilic parts of organisms for example animal fat The Koc reflects the propensity of

a compound to adsorb to organic matter found in soil or sediments The potential for a constituent to

adsorb to soil and sediment particles will affect migration through soil and aquifer materials as well

as migration from surface water to sediments Adsorption potential typically is expressed in terms of

a partition coefficient (Kj) which is the ratio of concentration of adsorbed constituent to

concentration of aqueous phase constituent Higher values of Kj indicate a greater potential for the

constituent to adsorb to soil sediments and aquifer materials The Kj for organic constituents can be

expressed as the product of Koc and fraction of organic carbon (foc) in soil or sediments (EPA

1989b) Koc values for benzo(a)pyrene range from a low of 398 000 millihters per gram (mL/g) to a

high of 1 900 000 mL/g and dibenz(a h)anthracene has a Koc value of 1 700 000 mL/g

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2 3 3 2 Toxicity Values

In describing chemical toxicity a distinction is made between carcinogenic and non carcinogenic

effects and two general criteria are used to describe the risk of toxic effects Estimated Lifetime

Cancer Risk (ELCR) for COPCs which are classified as potential human carcinogens and the hazard

quotient (HQ) for the non carcinogenic effects of COPCs In calculating RBC goals for constituents

acceptable target cancer and non cancer risks must be assumed For this assessment RBCs based on

potential cancer effects are presented for target cancer risks (TCR) of 1 x 10"4 and 1 x 1Q"6

There are no EPA derived non carcinogenic toxicity criteria available for the COPCs identified for

this Unit Group All of the COPCs are considered potentially carcinogenic and RBCs were

calculated using the cancer slope factors (CSFs)

EPA typically has required that potentially carcinogenic constituents be treated as if minimum

threshold doses do not exist (EPA, 1986) The regulatory dose response curve used for carcinogens

only allows for zero risk at zero dose Therefore some level of risk is assumed to be present for all

environmental doses

To estimate the theoretical response of environmental doses various mathematical dose response

models are used EPA uses the linearized multi stage model for low dose extrapolation (Munro and

Krewski 1981) This model assumes that the effect of the carcinogenic agent on tumor formation

seen at high doses in animal data is basically the same at low doses In deriving toxicity criteria for

carcinogenic effects the cancer slope factor (CSF) the linearized multi stage model has been

applied

Identification of constituents as known, probable or possible human carcinogens is based on EPA s

weight of evidence classification scheme in which chemicals are systematically evaluated for their

ability to cause cancer in mammalian species and conclusions are reached about potential to cause

cancer in humans The EPA classification scheme (EPA 1989a) contains six classes based on weight

of available evidence as follows

A known human carcinogen

Bl probable human carcinogen limited evidence in humans

B2 probable human carcinogen sufficient evidence in animals and inadequate data in

humans,

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C possible human carcinogen limited evidence in animals

D inadequate evidence to classify and

E evidence of non carcmogemcity

Available CSFs tumor sites and cancer classifications for COPCs are presented in Table 2 5 The

tiered approach to human health risk assessment (Integrated Risk Information System [IRIS] 2001)

is applied in this risk assessment Cancer slope factors are applied to mgestion dermal and

inhalation exposure pathways The CSFs for COPCs are listed in Table 2 5 EPA verified CSFs and

cancer classifications have been limited to the EPA Integrated Risk Information System (IRIS 2001)

Dose response information that is not verified but is reported in EPA Region IX (2000) and EPA

Region ffl (1996a) or by the EPA Environmental Criteria and Assessment Office (ECAO) was

considered qualitatively in this report Because toxicity values for dermal exposure are rarely

available the oral CSFs were adjusted to an absorbed dose using constituent specific oral absorption

efficiency (85% for PAHs) as recommended by EPA (1989a) to assess dermal exposure A 10%

dermal absorption efficiency was used for dermal exposure to PAHs in soil

2 4 RELEASE MECHANISMS, MIGRATION PATHWAYS AND EXPOSUREPATHWAYS

This section discusses potential release mechanisms that have led to the current impacts to

subsurface soil at the Unit Group Possible secondary release mechanisms and migration pathways

for constituents in subsurface soil and potential exposure pathways for human receptors are

presented This UCM information is presented in Figure 2 3

241 Primary Release Mechanisms

The Furnace Group is located in the central area of the plant inside buildings with concrete floors

Units within the Unit Group are furnaces and heat treatment equipment Unit histories and types of

detected constituents for the Unit Group were reviewed to determine the most likely original sources

of constituents Based on available information the primary constituents detected at this Unit Group

includes PCBs SVOCs, and VOCs Primary release mechanisms include leaks and spills from

hydraulic systems that historically may have contained PCBs and contact cooling water that is

captured and recycled Contact cooling water may contain small amounts of oil which is used to

lubricate casting pits VOCs were constituents in materials used at the Former Paint Line (IPO 04)

Furnace Unit Group RBC ReportRev Furrt Grp pc2 219 Rev May 2004

242 Potential Secondary Release Mechanisms and Migration Pathways

Secondary release mechanisms associated with the Unit Group include discharge of contact cooling

water to NPDES Outfall 006 which normally is pumped to the Water Reclamation Facility

(CWM 12) for treatment but could result in transport to the Mississippi River in times of heavy

precipitation Since cooling water discharges upgradient of lift stations on Outfall 006 significant

discharge of contaminants to the Mississippi is unlikely However this was potentially a significant

historical release mechanism Water within the Storm Sewer System was evaluated in the RBC

Report for the Sewer Unit Group Although the plant s current groundwater pump and treat system

captures shallow bedrock groundwater across a significant portion of the facility it is possible that

groundwater in this zone near the eastern facility boundary flows off site to the east The

Groundwater RI provides an evaluation of the potential for off site migration of groundwater

243 Potential Human and Ecological Exposure Pathways

Incidental exposure to subsurface soil may occur if repair to utility lines is performed or if soils are

excavated for construction work Surface soil surface water and sediment are not present within the

Unit Group since all of the units occur within main plant buildings There is no routine exposure to

constituents in groundwater beneath the Unit Group because groundwater is not used or encountered

during operations at this Unit Group The UCM (Figure 2 3) includes the excavation repair worker

and the excavation construction worker as the potential receptors for subsurface soil

The Exposure Menu includes two potential human receptors for surface soil and subsurface soil

combined the repair worker and the construction worker However surface soil is not present at the

Unit Group since the entire unit group is within buildings A repair worker may contact subsurface

soils while repairing underground utilities in the area covered by the Furnace Group The

construction worker may contact subsurface soil during the construction of building foundations

installation of new equipment or facilities etc This Unit Group is located in areas that may

potentially be targeted for future development where the construction worker may become an

applicable receptor Both the excavation repair worker and the excavation construction worker are

evaluated as potential receptors for subsurface soil in this risk assessment

Because the Furnace Group is not identified as a perimeter unit in the CSM the off site resident

groundwater exposure pathway was not identified as a potentially relevant exposure scenario A

more detailed discussion of exposure assessment is presented in Section 3 0

Furnace Unit Group RBC ReportRev Furn Grp pc2 2 20 Rev May 2004

3 0 EXPOSURE ASSESSMENT

The objective of this Exposure Assessment is to assess the exposure of human receptors to

constituents in environmental media within the Furnace Group This exposure assessment evaluates

activities and constituents within subsurface soil and issues related to current operations A

discussion of potential human exposure scenarios was presented in Section 253 This section

provides a review of human exposure scenarios outlined in the Exposure Menu that are applicable to

the Unit Group The Exposure Menu provides Alcoa specific exposure scenarios for soil

groundwater surface water and sediment The exposure scenarios acknowledge current and

anticipated future industrial land use of the Alcoa Davenport Works The scenarios also

acknowledge limited access to the site by the public

Selected human exposure scenarios are used in Section 4 0 to develop RBC values for subsurface

soil at the Furnace Group As discussed previously no ecological habitat is present at the Unit

Group Only human exposure pathways are discussed in the following sections

3 1 EXPOSURE SCENARIOS

As discussed in Section 253 the excavation repair worker scenario and the excavation construction

worker scenario are identified as relevant current scenarios for evaluating RBCs for subsurface soil

at the Unit Group As a conservative measure Alcoa evaluated whether other site specific scenarios

may be applicable in the future should there be a change in Alcoa s land use at the unit A review of

the Menu of Alcoa Specific Site Wide Exposure Scenarios in the 1995 AOC revealed that the

frequent occasional and infrequent on site workers are potential future exposure scenarios These

additional scenarios are also evaluated in this report as an expanded analysis to determine whether

any current or likely future Alcoa use of the property could result in a risk to workers The exposure

routes include incidental ingestion of soil dermal contact to exposed areas of the skin and inhalation

of volatiles and particulates are possible for each exposure scenario The exposure parameters

outlined in the Exposure Menu for the aforementioned scenarios are listed in Table 3 1

3 2 EXPOSURE POINT CONCENTRATIONS

The EPC values are compared to the calculated RBCs for subsurface soil in Section 4 0 of this report

For those constituents selected as COPCs the procedure used to determine EPCs has been agreed

upon by Alcoa and EPA (EPA 1996b) The first step in the determination of EPCs is to evaluate the

amount of constituent specific data available to perform statistical calculations If the constituent is

Furnace Unit Group RBC Report870361 233 AQ 3 1 December 2001

detected and there are less than five data points available for statistical evaluation then the

maximum detected concentration is used as an estimate of the EPC If the size of the data set is

determined to be adequate for statistical evaluation the data set is further evaluated to determine the

percentage of data reported as non detect (ND) Selection of the statistical methodology to

estimate EPCs is based on the percentage of ND data for each COPC None of the COPCs at this

Unit Group were detected therefore each EPC is represented by the range of SQLs These are

presented in Table 3 2

Furnace Unit Group RBC Report870361 233 AQ 32 December 2001

4 0 RBC CALCULATIONS AND COMPARISONS

This section presents RBC calculations for COPCs in subsurface soil comparisons with EPCs at the

Furnace Group and associated uncertainties In this section calculated RBCs are compared to EPC

values for the excavation repair worker scenario and the excavation construction worker scenario In

addition as a conservative measure Alcoa evaluated whether other site specific scenarios may be

applicable in the future should there be a change in Alcoa s land use at the unit A review of the

Menu of Alcoa Specific Site Wide Exposure Scenarios in the 1995 AOC revealed that the frequent

occasional and infrequent on site workers are potential future exposure scenarios These scenarios

are included in the evaluation below

RBCs are target soil concentrations that are protective of human health and are based on relevant and

conservative exposure scenarios and acceptable levels of cancer and non cancer risk Two general

criteria are used to describe the risk of toxic effects theoretical excess lifetime cancer risks (ELCR)

for COPCs that are classified as potential human carcinogens and Hazard Quotients (HQ) for

COPCs that are classified as non carcinogenic The ELCR and the HQ for each constituent is

summed to estimate a Total ELCR and a Hazard Index (HI) for each pathway The Total ELCRs and

His for each exposure pathway are summed to estimate the Total Cancer Risk (TCR) and the Target

Hazard Indices (THJ) for each receptor To calculate RBCs appropriate levels of acceptable cancer

and non cancer risks must be selected EPA has determined that TCR values between 10 6 and 10 4

may not warrant remediation (EPA 199la and EPA 1991b) Therefore RBCs based on potential

cancer effects were calculated for the TCR values of 10 6 and 10 4 RBCs for potential non cancer

effects are calculated using a THI value of 1 which corresponds to constituent exposure doses equal

to the EPA verified RfD levels considered protective of human health However the COPCs for this

Unit Group were only evaluated for potential cancer effects because RfDs are not available

4 1 CURRENT AND FUTURE RECEPTORS

RBCs for subsurface soil based on the excavation repair worker scenario and the excavation

construction worker scenario were calculated The equations used for calculating RBCs and a sample

calculation for the excavation repair worker are presented in Table 4 1 COPC specific RBCs for the

repair worker receptor are presented in Table 4 2 and COPC specific RBCs for the construction

worker receptor are presented in Table 4 3 Both of the exposure models include incidental ingestion

of soil dermal uptake from soil on exposed skin and inhalation of particulates from soil The

inhalation of volatiles was not evaluated in the exposure models as the COPCs in the risk assessment

Furnace Unit Group RBC Report870361 233 AQ 4 1 December 2001

are considered to be non volatile Route specific RBCs calculated for the three intake routes are

combined into a single RBC value protective of simultaneous exposure via all three routes Table 4 2

and 4 3 present route specific oral dermal and inhalation RBCs for cancer effects based on a TCR of

10 ^ for the excavation repair worker and the excavation construction worker respectively The non

cancer RBCs for benzo(a)pyrene and dibenz(a h)anthracene were not calculated because the EPA

verified RfD levels for these constituents are unavailable

Tables 4 4 and 4 5 compare calculated repair worker and construction worker RBCs to the calculated

EPCs for COPCs in subsurface soil respectively Cancer RBCs for both benzo(a)pyrene and

dibenz(a h)anthracene are 10 mg/kg under the repair worker scenario and 21 mg/kg under the

construction worker scenario while the EPC for each constituent is <0 34 to <0 4 mg/kg No

constituent specific EPC exceeds any of the respective RBCs for these receptors

4 2 POTENTIAL FUTURE RECEPTORS

Potential future receptors that may be exposed to surface soil in the event of an Alcoa land use

change are the frequent occasional and infrequent on site workers Surface soil RBCs calculated for

these receptors in the Bone Yard RBC Report (IT 2001) were used to evaluate the potential future

risks for this Unit Group Tables 4 6 through 4 8 compare calculated frequent occasional and

infrequent on site worker RBCs respectively to the EPCs of COPCs in soil at the Furnace Group

Because surface soil is not present at the Furnace Group the EPCs of subsurface soil COPCs were

used for comparison with on site worker RBCs

This expanded analysis of potential future receptors shows that under the frequent occasional and

infrequent on site worker scenarios the two COPCs (benzo(a)pyrene and dibenz(a h)anthracene)

have EPCs based on SQLs that do not exceed the RBCs for a TCR of 10 6

4 3 UNCERTAINTY ANALYSIS

The procedures used m any quantitative risk assessment exercise such as in the calculation of RBCs

result in conditional estimates of risk based on many assumptions about exposure and toxicity

Uncertainties are inherent in every aspect of a quantitative risk assessment These affect the level of

confidence that can be placed in the final results Because of this uncertainty the assumptions tend to

be health protective and conservative in nature

Furnace Unit Group RBC Report870361 233 AQ 42 December 2001

A careful analysis of the critical areas of uncertainty in risk assessment is a very important part of the

risk assessment process EPA (1992a) guidance stresses the significance of providing a complete

analysis of uncertainties so risk managers will take these uncertainties into account when evaluating

risk assessment conclusions The inherent uncertainty of the assumptions and whether they are

reasonable must be considered concurrently with the estimated risk values when using findings of a

risk assessment to make risk management decisions The following sections enumerate some of the

uncertainties with the greatest potential impact on the results of the RBC calculations

Non-detected COPCs Including constituents that were not detected in the quantitative evaluation is

a very conservative approach In this RBC report none of the COPCs were detected in soil samples

These constituents [benzo(a)pyrene and dibenz(a h)anthracene] each had a detection limit that

exceeded their corresponding PRO in twenty percent or more of the total number of samples

analyzed Although they have been labeled as constituents of potential concern these constituents

may not have been present in any samples or may have been present at concentrations below the

PRO

Conservatism of Exposure Scenario Assumptions Although the excavation workers and on site

workers are assumed to be present at the site for 8 hours per day their actual work activities may

vary throughout the day For example the repair worker is assumed to be exposed to soil for 8 hours

per day for 5 days per year for 25 years On one hand the repair worker could hypothetically be

exposed for more than 8 hours per day and more than 5 days per year especially in consideration of

the entire unit group or in consideration that a repair worker may also be exposed to other FSA units

However, on the other hand the actual exposure to contaminated soil may be considerably less given

that FSA units make up a relatively small portion of the overall plant in which the repair workers

perform their tasks In addition, it is unlikely that workers would be in an excavation and exposed to

soil 8 hours or more in a given day

Similarly the frequent on site worker is assumed to be exposed to soil for 8 hours per day for 190

days per year for 25 years The actual exposure to contaminated soil for this receptor may also be

considerably less given that the vast majority of the ground surface where the frequent on site

workers perform most of their tasks is paved

Furnace Unit Group RBC ReportRev Fum Grp pc2 4 3 Rev May 2004

Additionally each of the exposure scenarios incorporates the exposed forearms into the total exposed

skin surface area It is unlikely that this will be the case during every exposure situation The worker

may wear long sleeve coveralls when working

Dermal Exposure Pathways EPA guidance regarding dermal exposure assessment (EPA 1992c)

indicates that in cases where the percentage of dermal absorbance of a constituent is less than 10%

and the same soil is evaluated for mgestion it is most likely not important to consider dermal

exposure pathways This may be the case for the COPCs in this risk assessment As stated in the

Region in Technical Guidance Manual Assessing Dermal Exposure from Soil (1998) the proposed

range for dermal absorption of semivolatile organics from soil was 1% to 10% in an experiment by

Ryan et al 1987 More specifically the Guidance Manual notes that Kao et al (1985) reported

approximately 3% dermal absorption of pure benzo(a)pyrene by in vitro human skin Region En

recommends accepting the 10% value as a conservative assumption of dermal absorption for

semivolatile organics however it is evident that the absorption factor may fall below 10% and

therefore may not be a major contributor total risk

Dose-Response Assessment-Potential Carcinogenic Effects Uncertainties are introduced in

animal to human extrapolation and high to low dose extrapolation Mathematical models are used to

estimate the possible responses associated to exposure to chemicals at levels far below those tested in

animals Humans are typically exposed to environmental chemicals at levels orders of magnitude

lower than the lowest dose tested in animals Such doses may be readily degraded by physiological

mechanisms in humans (Ames 1987 Abelson 1990)

Surrogate Non-Carcinogenic RBCs Typically surrogate chemicals are used in the screening of

data for COPC identification or to develop RBCs when no other toxicity information is available for

a compound For this Unit Group the COPCs are the high molecular weight carcinogenic PAHs

Cancer slope factors were available for these compounds and site specific carcinogenic RBCs were

calculated Although noncarcmogenic toxicity information is lacking for these compounds these

compounds are assessed principally based on their carcmogemcity (EPA 1993 Provisional Guidance

for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons ORD EPA/600/R 93/089

July 1993) Because carcinogenic endpomts occur at a lower threshold of exposure for these

compounds than do the noncarcmogenic endpomts (ATSDR, 1998) the use of surrogate

noncarcmogenic RBCs would not benefit the remedial decision making process for this particular

unit

Furnace Unit Group RBC ReportRev Furn Grp pc2 4 4 Rev May 2004

Amount of Available Data Available data were used to evaluate potential risks however one unit

the No 8 and No 9 Vertical Heat Treatment Furnaces (IPH 09) was not represented in the EPC by

any data Due to the difficulty of obtaining data from below the floor in an active area of the plant

no additional investigation is planned Use of data collected at units where similar industrial

processes occur to calculate EPCs likely provides an accurate estimate of subsurface conditions

However the lack of data at the No 8 and No 9 Vertical Heat Treatment Furnaces underscores the

importance of Alcoa s Drilling and Digging Permit Program In the event an Alcoa land use change

will expose on site workers to soils currently under IPH 09 or work in the area will result in

exposure to excavation repair workers or construction workers soil samples will need to be collected

under the Digging Permit Program

Furnace Unit Group RBC ReportRev Furn Grp pc2 4 5 Rev May 2004

5 0 CONCLUSIONS

Conclusions based on the risk assessment results are provided below Mo ecological habitat is present

at the Unit Group therefore only human exposure pathways are evaluated in the risk assessment

Surface soil surface water and sediment are not present within the Unit Group since all of the units

occur within main plant buildings There is no routine exposure to constituents in groundwater

beneath the Unit Group because groundwater is not used or encountered during operations at this

Unit Group

Soil data and results from a program to test hydraulic systems and gearboxes presented in Appendix

A suggest that contaminants are not present in soil beneath the unit group in significant quantities

Soil data were generally collected in conjunction with construction projects to determine if

constituents were present in soil Since no significant quantities of site contaminants were identified

more comprehensive data collection efforts are not warranted Soil data collected at the Furnace

Group are appropriate for use in the risk evaluation because samples were collected from areas

where future repairs may be required

Process knowledge also indicates that significant subsurface contamination would not be expected

beneath units that constitute the Furnace Group because the units do not generally use large volumes

of solvents or PCB containing oils The greatest opportunity for potential release comes from

leakage to sumps and pits located below floor level under equipment These pits and sumps are

periodically pumped during maintenance activities The recovered material is treated at the

Industrial Waste Treatment Facility (FSA Unit CWM 10) where PCB testing is routinely performed

to ensure that materials are appropriately handled This process knowledge helps confirm that

existing soil data are adequate for evaluation of the Unit Group

A screening of these data identified benzo(a)pyrene and dibenz(a h)anthracene as COPCs in

subsurface soil because their SQLs exceeded their respective Region IX PRGs in greater than 20

percent of samples The EPCs of the COPCs (maximum SQLs) were compared with 10 6 cancer

RBCs The non cancer RBCs for benzo(a)pyrene and dibenz(a h)anthracene were not calculated

because the EPA verified RfD levels for these constituents are unavailable The risk assessment

indicates that there are no unacceptable cancer risks to the current and future exposure scenarios

(excavation construction and repair workers) In addition an expanded analysis of future potential

Furnace Unit Group RBC Report870361 233 AQ 5 I December 2001

receptors (frequent occasional and infrequent on site workers) indicates that there would be no

unacceptable cancer risks

The risk assessment indicates that current and future cancer risks posed by the subsurface soil in the

area of the Furnace Group are below EPA s Target Cancer Risk Range of 10"6 to 10^ This

conclusion is supported by data collected from hydraulic units and gearboxes under a program to

identify and eliminate sources of residual PCBs in equipment at Davenport However unit EPH 09

(No 8 and No 9 Vertical Heat Treatment Furnaces) will be identified in the Plant s Short Term

Management Plan (STMP) as a unit where data are lacking The lack of data at IPH 09 underscores

the importance of Alcoa's Drilling and Digging Permit Program In the event an Alcoa land use

change will expose on site workers to soils currently under IPH 09, or work in the area will result in

exposure to excavation repair workers or construction workers soil samples will need to be collected

under the Digging Permit Program The listing of this unit in the STMP may be withdrawn in the

future if data are collected that show there are no unacceptable risks associated with the unit

Furnace Unit Group RBC ReportRev Fum Grp pel 5 2 Rev May 2004

6 0 REFERENCES

Abelson 1990 Incorporation of New Science into Risk Assessment Science 2501947

Alcoa 1998 Davenport Works PCB Management Plan Revision 4 January 1998

Ames B Magraw R Gold S 1987 Ranking Possible Carcinogenic Hazards Science 236271 273

Agency for Toxic Substances and Disease Registry (ATSDR) 1990 lexicological Profile forBenzo(a)pyrene Public Health Service U S Department of Health and Human ServicesAtlanta Georgia

Agency for Toxic Substances and Disease Registry (ATSDR) 1998 Toxicological Profile forPolycyclic Aromatic Hydrocarbons United States Department of Health and HumanServices August 1995

Foreman WT and TF Bidleman 1985 Vapor Pressure Estimates of Industrial PCBs andCommercial Fluids Using Gas Chromatography Retention Data Journal ofChromatography 330203216

Geraghty & Miller Inc 1991a Report of Findings Soil Sampling Investigation at the VFX FurnaceExcavation January 6 1991 02 005 07 0038

Geraghty & Miller Inc 1991b Quality Assurance Program Plan (QAPP) for CERCLA AssessmentActivities at the Alcoa Davenport Works Plant Riverdale Iowa

Geraghty & Miller Inc 1992 Initial Facility Site Assessment Report Alcoa Davenport WorksRiverdale Iowa April 1992

Geraghty & Miller Inc 1995a Conceptual Site Model (CSM) October 1995

Geraghty & Miller Inc 1995b Menu of Facility Specific Exposure Scenarios for Soil SurfaceWater Sediment and Groundwater Alcoa Davenport Works (Exposure Menu)

Howard PH 1989 Handbook of Environmental Fate and Exposure Data for Organic ChemicalsVolume I Large Production and Priority Contaminants Lewis Publishers Inc ChelseaMichigan pp 574

Howard PH RS Boethlmg WF Jarvis WM Meylan and E M Michalenko 1991 Handbookof Environmental Degradation Rates Lewis Publishers Inc Chelsea Michigan pp 725

Hazardous Substances Database (HSDB) 1997 MEDLARS The National Library of MedicinesOnline Network U S Department of Health and Human Services Public Health ServiceNational Institutes of Health Bethesda MD

Integrated Risk Information System (IRIS) 2001 MEDLARS The National Library of MedicinesOnline Network U S Department of Health and Human Services Public Health ServiceNational Institutes of Health Bethesda Maryland

Furnace Unit Group RBC Report870361 233 AQ 6 1 December 2001

Kao JK F Patterson and J Hall 1985 Skin penetration and metabolism of topically appliedchemicals in six mammalian species including man An in vitro study with benzo(a)pyreneand testosterone Toxicol Appl Pharmacol 81 502 516

Klassen C D ed 1996 Casarett and Doull s Toxicology The Basic Science of Poisons 3rd EditionCasarett and Doull eds MacMillan Publishing New York

Lyman WJ WF Reehl and D H Rosenblatt 1990 Handbook of Chemical Property EstimationMethods American Chemical Society Washington D C

Montgomery JH and LM Welkom 1990 Groundwater Chemicals Desk Reference LewisPublishers Inc Chelsea Michigan pp 640

Munro and Krewski 1981 Risk assessment and regulatory decision making Food Cosmet Toxicol19549 560

Owen BA 1990 Literature Derived Absorption Coefficients for 39 Chemicals Via Oral andInhalation Routes of Exposure Reg Toxicol Pharmacol 11237252

Ryan E A E T Hawkins et al 1987 Assessing Risk From Dermal Exposure at Hazardous WasteSites In Bennett G and J Bennett eds Superfund 87 Proceedings of the Eighth NationalConference November 16 18 Washington DC The Hazardous Control Research InstitutePp 166 168

Shen TJ 1982 Air Quality Assurance for Land Disposal of Industrial Waste EnvironmentalManagement Vol 6 pp 297 305

United States Environmental Protection Agency (EPA) 1986 Guidelines for Carcinogenic RiskAssessment Federal Register 51 33992

United States Environmental Protection Agency (EPA) 1988 Laboratory Data ValidationFunctional Guidelines for Organic and Inorganic Analyses

United States Environmental Protection Agency (EPA) 1989a Transport and Fate of Contaminantsin the Subsurface Center for Environmental Research Information Cincinnati OhioSeminar Publication

United States Environmental Protection Agency (EPA) 1989b Risk Assessment Guidance forSuperfund Human Health Evaluation Manual Volume I Part A Interim Final Office ofEmergency and Remedial Response Washington DC EPA 540/1 89/002 December1989

United States Environmental Protection Agency (EPA) 1991a Risk Assessment Guidance forSuperfund Human Health Evaluation Manual Part B Development of Risk basedPreliminary Remediation Goals Office of Solid Waste and Emergency ResponseWashington DC OSWER Directive 9285 7 01B December 13

United States Environmental Protection Agency (EPA) 1991b Risk Assessment Guidance forSuperfund Volume I Human Health Evaluation Manual Supplemental Guidance

Furnace Unit Group RBC Report870361 233 AQ 62 December 2001

Standard Default Exposure Factors Interim Final Office of Emergency and RemedialResponse Washington DC OSWER Directive 9285 6 03 March 25 1991

United States Environmental Protection Agency (EPA) 1992a Guidance for Data Useabihty in RiskAssessment (Part A) Final Office of Emergency and Remedial Response Washington DC92857 09A April 1992

United States Environmental Protection Agency (EPA) 1992b Risk Assessment Guidance forSuperfund Volume I Human Health Evaluation Manual Supplemental Guidance DermalRisk Assessment Interim Guidance Office of Emergency and Remedial ResponseWashington DC August 18 1992

United States Environmental Protection Agency (EPA) 1992c Dermal Exposure AssessmentPrinciples and Applications Office of Research and Development Washington DC EPA600/8 91/011B

United States Environmental Protection Agency (EPA) 1993 Provisional Guidance for QuantitativeRisk Assessment of Polycychc Aromatic Hydrocarbons Office of Research andDevelopment Washington D C EPA/600/R 93/089

United States Environmental Protection Agency (EPA) 1995a Docket No VII 95 F 0026 ConsentOrder August 1995

United States Environmental Protection Agency (EPA) 1995b Chemical and Locatom SpecificARARs Analysis Report for the Alcoa Davenport Works Site Riverdale IowaDecember 22 1995

United States Environmental Protection Agency (EPA) 1996a Region III Risk BasedConcentration Table

United States Environmental Protection Agency (EPA) 1996b Addendum No 1 to theAdministrative Order on Consent Docket No VII 95 F 0026

United States Environmental Protection Agency (EPA) 1997 EPA Health Effects AssessmentSummary Tables

United States Environmental Protection Agency (EPA) 1998 Region III Technical GuidanceManual Risk Assessment Assessing Dermal Exposure from Soil EPA/903 K 95 003

United States Environmental Protection Agency (EPA) 2000 Region IX Preliminary RemediationGoal Tables

Wadsworth/Alert Laboratories 1990 Quality Assurance Program Plan

Furnace Unit Group RBC Report870361 233 AQ 63 December 2001

TT^n?22 1Review of Data Usability Criteria for Risk Assessment

Furnace Group

Alcoa Davenport Works Riverdale Iowa

Sample Numbers)

Dat

a S

ourc

es

Com

patib

le

Pla

nnin

g D

ocum

enta

tion

Com

plet

ed

Fie

ld a

nd A

na

lytic

al

Doc

umen

tatio

n C

ompl

eted

Ana

lytic

al M

etho

ds &

Det

ectio

n Lim

its I

dentif

ied

Sam

plin

g M

etho

dolo

gyB

iase

d or

Ran

dom

Data Quality Indicators Satisfied

Com

plet

enes

s

Com

para

bilit

y

Rep

rese

ntat

iven

ess

Pre

cisi

on

Acc

urac

y

Analy

tical

Dat

a R

evie

wP

erfo

rmed

Dat

a In

clud

ed i

n R

isk

Bas

ed C

alcu

latio

ns

Comments

Report of Findings Soil Sampling Investigation at the VFX Furnace Excavation (Jan 1992)

B 1 B2

VMX1S VMX2S VMX3S

Y

Y

N

N

Y

Y

Y

Y

B

B

N

Y

Y

Y

Y

Y

Y

Y

Y

Y

N

N

Y

Y

May be biased high for VOCs and PCBs as samples with the highest

field readings were submitted to the lab

VOC data from composite samples were not used PCB data wereused May be biased high for PCBs as samples with the highest fieldreadings were submitted to the lab

Soaking Pits Investigation (Oct 1997)

SOK. HA01 toHA06 Y Y Y Y R Y Y Y Y Y Y Y

Digging Permit Sampling (Nov 1998)

810HA01 810HA02 and810HA03 Y N Y Y R Y Y Y Y Y N Y

Gearbox and Hydraulic System Testing (1981 to present)

Oil samples N N N N NA U U Y U U N N

Data from the oil testing program was used qualitatively to support

conclusions of the risk evaluation Results are provided in Appendix

A

Y=Yes N=No U=Unknown B=Biased R=Random NA=Nol Applicable

870361 233 AQ Page 1 of 1Furnace Group RBC Report

December 2001

Table 2 2Soil Samples Included in Risk Calculations

Furnace Group, Alcoa Daveport WorksRiverdale Iowa

Sample Name

B 1B 2SOK HA01SOK HA02SOK-HA03SOK-HA04SOK-HA05SOK HA06 (Duplicate of SOK HA04)VMX1SVMX2SVMX3S810HA01810HA02810HA03

870361 233 AQ Page 1 of 1Furnace Group RBC Report

December 2001

TABLE 2-3Identification of COIs and COPCs

for Surface/Subsurface SoilFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent CAS No

Constituents of Interest (COIsFrequency

of DetectionRange of SQLs

(mg/kg)Region K PRG(1)

(mg/kg)/SQLs>PRG

Retain as RationaleCOI

Constituents of Potential Concern (COPCs)Range

of Detects(mg/kR)

Max Detector SQL>PRG

Retain as RationaleCOPC

POLYCHLORINATED BIPHENYLSAroclor 1016Aroclor 1221Aroclor 1232Aroclor 1242Aroclor 1248Aroclor 1254Aroclor 1260Aroclor 1268

12674-1 1 211104-28211141 1655346921 912672 29-611097-69 11109682511100 14^

0 / 100 / 130 / 130 / 104 / 130 / 130 / 130 / 3

0017 00410017 050017 050017 00410017 05002 05002 0505 05

2 87E+01OOE+00OOE+00OOE+00OOE+00OOE+00OOE+00OOE+00

00000000

No SQL<PRGNo Not Site-Wide COINo Not Site-Wide COINo SQL<PRGYes DetectionNo SQL<PRGNo SQL<PRGNo SQL<PRG

Not a COINot a COINot a COINot a COI

0098 071Not a COINot a COINot a COI

NoNoNoNoNoNoNoNo

NANANANANo Max detect,SQL<PRGNANANA

SEMFVOLATILE ORGANIC COMPOUNDS1,2 3 Tnchlorobenzene1 ,2 4 Tnchlorobenzene1,2 4 Tnmethylbenzene1,2 Dichlorobenzene1 3 5 Tnmethylbenzene1 3 Dichlorobenzene1 4-Dichlorobenzene245 Tnchlorophenol246 Tnchlorophenol2 4-Dichlorophenol2 4-Dimethylphenol2 4-Dmitrophenol2 4-Dmitrotoluene2 6-Dmitrotoluene2-Chlorophenol2 Methylnaphthalene2 Methylphenol2 Nitroanilme2 Nitrophenol3 3 Dichlorobenzidme3 Nitroanilme4 6 Dirutro-o-cresol4 Bromophenyl phenyl ether4-Chloroanihne4-Chlorophenyl phenyl etherp-Chlorotoluene4 Methylphenol4 Nitroanilme4 NitrophenolAcenaphthene

87-61-6120-82 195-63-695501108-67 8541 73 1106-46-79595-488-06-2120 83 2105-67 951285534-52 1606 20-29557891 57-695-4878874-48875591 94-199-092534 52 1101 55 3106-4787005 72 310M3^106-44-5100-01-6100-02 783329

0 / 30 / 80 / 30 / 80 / 30 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 50 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 30 / 50 / 80 / 80 / 8

0025 00250025 040005 0005034 04

0005 0005034 04034 04034 04034 04034 04034 04036 19034 04034 04034 04034 04034 04036 19034 04036 19036 19036 19034 04034 04034 04

0005 0005034 04036 19036 19034 04

3 OOE+033 OOE+031 70E+023 70E+02698E+015 18E+018 13E+00881E+042 24E+02264E+031 76E+041 76E+03881E+02881E+02241E+02

89E+02440E+045 03E+017 05E+035 48E+005 03E+01_

_

3 52E+03_

5 68E+024 40E+035 03E+017 05E+03384E+04

000000000000000000000000000000

No SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo Not Site Wide COINo Not Site-Wide COINo SQL<PRGNo Not Site-Wide COINo SQL<PRGNo SQL<PRGNo SQIXPRGNo SQL<PRGNo SQL<PRG

Not a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COI

NoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNo

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

RevT23pc l xls Page 1 of 4Furnace Group RBC Report

Rev May 2004

TABLE 2-3Identification of COIs and COPCs

for Surface/Subsurface SoilFurnace Group Alcoa Davenport Works, Riverdale Iowa

Constituent

AcenaphthyleneAnthraceneBenzidmeBenzo(a)anthraceneBenzo(a)pyreneBenzo(b)fluoran thereBenzo(g h i)peryleneBenzo{k)fluorantheneBenzoic AcidBenzyl alcoholzieta-Chloronaphthaleneuis(2-Chloroethoxy)methanebis(2 Chloroethyl)etherbis(2-Chloroisopropyl)etherbis(2 Ethylhexyl)phthalateButyl benzyl phthalateCarbazole^hryseneDibenz(a,h)anthraceneDibenzofuranDibutyl phthalateDiethyl phthalateDimethyl phthalateDi n-octyl phthalateFluorantheneFluoreneHexachlorobenzenerlexachlorobutadieneHexachlorocyclopentadieneHexachloroe thanelndeno(l 2 3-cd)pyreneIsophoroneNaphthaleneNitrobenzenen Nitroso di n propylammeN Nitrosodimethylammen Nitrosodiphenylammeo-Chlorotoluenep-Chloro-m-cresol3entachlorophenol

CAS No

208 96-8120-127928755655350328205 99 2191 242207-08 96585-0100-51-691 587111 91 1111-44-4108-60 111781 785-68786748218-01 953703132-64-984-74-284-66-2131 11 311784-0206-44-086-73711874 187-68377-47-46772 1193 39 57859 191 20398953621-64-76275986-30-695-4985950787865

Constituents of Interest (COIs

Frequencyof Detection

0 / 80 / 80 / 30 / 80 / 80 / 80 / 80 / 80 / 30 / 30 / 80 / 80 / 80 / 50 / 80 / 50 / 50 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 110 / 80 / 80 / 80 / 80 / 80 / 80 / 80 / 30 / 80 / 30 / 80 / 8

Range of SQLs(rag/kg)

034 04034 04036 04034 04034 04034 04034 04034 040 73 0 79036 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04034 04

0025 04073 19034 04034 04034 04034 04034 04034 04036 04034 04

0005 0005034 04036 19

Region DC PRG(1)

(mg/kg)

384E+041 OOE+051 07E-022 89E+002 89E-012 89E+00542E-KM2 89E+011 OOE+051 OOE+05273E+04_

620E-018 08E+001 76E+021 OOE+051 23E+022 89E+022 89E-015 06E+03881E+041 OOE+051 OOE+05100E+04301E+04331E+041 54E+003 16E+015 90E+031 76E+022 89E+002 60E+031 89E+021 14E+02352E-01484E-025 03E+025 68E+02_

1 11E+01

/SQLs>PRG

00

1000

8750000000000000

8750000000000000000

1000000

Retain as RationaleCOI

No SQL<PRGNo SQL<PRGNo Not Site Wide COINo SQL<PRGYes SQL>PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo Not Site-Wide COINo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGYes SQL>PRGNo SQIXPRGNo SQIXPRGNo SQLXPRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo Not Site Wide COINo SQL<PRGNo SQL<PRGNo Not Site-Wide COINo SQL<PRG

Constituents of Potential Concern (COPCs)

Rangeof Detects(mg/kg)

Not a COINot a COINDNot a COINDNot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINDNot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINDNot a COINot a COINot a COINot a COI

Max Detector SQL>PRG

NoNoNoNoYesNoNoNoNoNoNoNoNoNoNoNoNoNoYesNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNo

Retain as RationaleCOPC

NANANANAYes SQL>PRGNANANANANANANANANANANANANAYes SQL>PRGNANANANANANANANANANANANANANANANANANANANANA

RevT23pc lx l s Page 2 of 4Furnace Group RBC Report

Rev May 2004

TABLE 2 3Identification of COIs and COPCs

for Surface/Subsurface SoilFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent

PhenanthrenePhenolPyrenePyridme

CAS No

85-01 8108 95 2129-00-011086-1

Constituents of Interest (COIs)

Frequencyof Detection

0 / 80 / 80 / 80 / 3

Range of SQLs(mg/kg)

034 04034 04034 04036 04

Region IX PRG(I)

(mg/kg)

542E+041 OOE+055 42E+04881E+02

/SQLs>PRG

0000

Retain as RationaleCOI

No SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRG

Constituents of Potential Concern (COPCs)Range

of Detects(mg/kg)

Not a COINot a COINot a COINot a COI

Max Detector SQL>PRG

NoNoNoNo

Retain as RationaleCOPC

NANANANA

VOLATILE ORGANIC COMPOUNDS1 1 1 ,2 Tetrachloroethane1 1 1 Tnchloroethane1 1,2,2 Tetrachloroethane1 1 2 Tnchloroethane1 1 Dichloroethane1 1 Dichloroethene1 1 Dichloropropene1 2 3 Tnchloropropane1,2 Dibromo-3-chloropropane1,2 Dibromoethane1,2 Dichloroethane1,2 Dichloroethene (total)1,2 Dichloropropane1 3 Dichloropropane2 2 Dichloropropane2 HexanoneAcetoneBenzeneBromobenzene3romodichloromethane3romoformBromomethaneCarbon disulfideCarbon tetrachlondeChlorobenzeneChlorobromomethaneChloroethaneChloroformChloromethanecis 1,2 Dichloroethenecis-1 3 Dichlorol propeneDibromochloromethaneDibromomethaneDichlorodifluoromethane±thylbenzene

630 20-671 55-67934-579-00-57534-375354563 58-696-18496-128106934107-06 2#N/A78875142 28 9594-20-7591 78-667-64-171432108 86 17527-47525274-83975 15-056235108 90 774-9757500-367-66-374873156 59 210061-01 5124-48 174-9537571 8100414

0 / 30 / 90 / 80 / 90 / 80 / 90 / 30 / 30 / 30 / 30 / 90 / 60 / 90 / 30 / 30 / 61 / 61 / 90 / 30 / 90 / 90 / 90 / 60 / 90 / 90 / 30 / 90 / 90 / 90 / 30 / 90 / 90 / 30 / 31 / 9

0005 00050005 000610005 000610005 000610005 000610005 000610005 00050 005 0 005005 005005 005

0005 0006100051 000610005 000610005 00050005 0005001 0024001 0024

0005 000610005 00050005 00061

00051 001001 002

00051 000610005 000610005 000610 005 0 005001 002

0005 00061001 002

0 005 0 0050005 000610 005 0 00610 005 0 0050015 00150005 00061

704E+001 40E+03898E-011 90E+002 06E+031 19E-011 61E-KJO309E-033 98E+004 83E-02765E-011 47E+02768&01768E-01768E-011 10E+026 22E+031 45E+00924E+012 36E+003 12E+021 31E-KM7 20E+02529E-015 43E+022 65E+00651E+00521E-012 66E+001 47E-KJ21 61E+00265E+002 36E+023 08E+022 30E+02

0000000

1000

1000000000000000000000000000

No SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo Not Site Wide COINo SQL<PRGNo Not Site-Wide COINo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGYes DetectionYes DetectionNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGYes Detection

Not a COINot a COINot a COINot a COINot a COINot a COINot a COINDNot a COINDNot a COINot a COINot a COINot a COINot a COINot a COI

0 069 0 0690006 0006

Not a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COINot a COI

0 006 0 006

NoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNo

NANANANANANANANANANANANANANANANANo Max detect SQL<PRGNo Max detect,SQL<PRGNANANANANANANANANANANANANANANANANo Max detect,SQL<PRG

R e v T 2 3 p c l xls Page 3 of 4Furnace Group RBC Report

Rev May 2004

TABLE 2 3Identification of COIs and COPCs

for Surface/Subsurface SoilFurnace Group Alcoa Davenport Works, Riverdale, Iowa

Constituent

IsopropylbenzeneMethyl ethyl ketoneMethyl isobutyl ketoneMethylene chloriden Butylbenzenen Propylbenzenep-Isopropyltoluenesec ButylbenzeneStyrenetert ButylbenzeneTetrachloroetheneToluenetrans 1,2 Dichloroethenetrans 1 3 DichloropropeneTnchloroetheneTrichlorofl uoromethaneVinyl acetateVinyl ChlorideXylenes (total)

CAS No

9882878933108 10-175-092104-51 8103-65 19987-6135 98 81004259806-6127 18-4108 88 3156-60-510061-02-679-01-675-69-4108-05-475-01-41330-20-7

Constituents of Interest (COIs

Frequencyof Detection

0 / 31 / 60 / 60 / 90 / 30 / 30 / 30 / 30 / 90 / 31 / 91 / 90 / 30 / 90 / 90 / 30 / 10 / 90 / 9

Range of SQLs(mg/kg)

0 005 0 0050 02 0 024001 0024

00051 0050005 00050005 00050005 00050 005 0 0050005 000610005 00050005 00060005 000610005 00050005 000610005 00061002 002N/A 001001 0015

0005 00061

Region K PRG(1>

(mg/kg)

522E+02277E+042 89E+03205E+012 40E+022 40E+025 22E-HD22 20E+021 70E+033 90E+021 87E-KJ15 20E+022 14E+021 61E+006 12E+002 OOE-K)31 40E+03830E-012 10E+02

/oSQLs>PRG

0000000000000000000

Retain as RationaleCOI

No SQL<PRGYes DetectionNo SQL<PRGYes DetectionNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGYes DetectionYes DetectionNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRGNo SQL<PRG

Constituents of Potential Concern (COPCs)Range

of Detects(mg/kg)

Not a COI0 28 0 28

Not a COI0 006 0 006

Not a COINot a COINot a COINot a COINot a COINot a COI

00031 00030 006 0 006

Not a COINot a COINot a COINot a COINot a COINot a COINot a COI

Max Detector SQI^>PRG

NoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNoNo

Retain as RationaleCOPC

NANo Max detect,SQL<PRGNANo Max detect SQL<PRGNANANANANANANo Max detect,SQL<PRGNo Max detect,SQL<PRGNANANANANANANA

NA Not applicable1 Region IX PRG for industrial soils (USEPA Region DC 2000)The following surrogate RBCs were used1,2 4-Tnchlorobenzene for 1 2 3 Tnchlorobenzene1,2 Dichloropropane for 1 3 Dichloropropane and 2,2 Dichloropropane1 3 Dichloropropene for 1 1 Dichloropropene1 3 Dichloropropene for cis and trans 1 3 Dichloropropene2 6 Dmitrotoluene for 2 4 Dmitrotoluene2 Nitroanilme for 3 Nitroanilme and 4-Nitroanilme4 Nitrophenol for 2 NitrophenolAcenaphthene for AcenaphthyleneAroclor 1260 for Aroclor 1268cis 1 2 Dichloroethene for 1,2 Dichloroethene (total)Dibromochloromethane for ChlorobromomethaneIsopropylbenzene for p-IsopropyltolueneNaphthalene for 2 Methylnaphthalenen Hexane for 2 Hexanone because both Hexane and 2 Hexanone are transformed in vivo to the same active metabolite 2 5 Hexanedione (KJassen, 1996)o-Chlorotoluene for p-ChlorotolucnePyrene for Benzo(g h i)perylene and Phenanthrene

R e v T 2 3 pel xls Page 4 of 4Furnace Group RBC Report

Rev May 2004

Table 2 4Physical and Chemical Properties of Constituents of Potential Concern Furnace Group

Alcoa Davenport Works Riverdale Iowa

ConstituentMolecular

Weight

(g/mol)

WaterSolubility

|_ (mg/l 25 C)

Specific

Gravity

VaporPressure

(mm Hg 25 C)

Henry s LawConstant

(atm m3/mol 25 C)

DifTusivity

(cm2/sec)

Koc

(ml/g)

Log KowSoil T 1/2

Low High

(days)

Semivoljtile Organic ConstituentsBenzo(a)pyrcneDiberu(a h)anthracene

252278

00038 0004000249 0005

1 35128

55C0910E 10(20 C)

2 40E 067 33E 09

0 046530 05707

398 000 1 900 0001700000

581 650597 650

57 529361 942

References EPA 2000 Foreman and Bidleman 1985 Howard etal 1991 HSDB 1997 Lymane ta l 1990 Montgomery and Welkom 1990 Shen 1982

atm m /molC

cm /secg/molKocKow

Atmospheres cubic meters per moleDegrees CelsiusSquare centimeters per secondGrams per moleOrganic carbon partition coefficient (organics)Octanol water partition coefficient

nig/L Milligrams per litermL/g Milliliters per grammm Hg Millimeters of mercuryNA Not availableT/ Half life

Range of koc is shown but the maximum value was used in RBC calculations

870361 733 AQ Page 1 of 1Furnace Group RBC Report

December 2001

Table 2 5

Toxicity Criteria'1' for Constituents of Potential Concern

Furnace Group Alcoa Davenport Works Riverdale Iowa

Constituents of

Potential Concern

Benzo(a)pyrene

Dibenz(a,h)anthracene

Oral CSF

(mg/kg day) '

73

73 W

Inhalation CSF

(mg/kg day) '

3 1 o >

3, (4)

CSF for Dermal t\p

(Adj For GI Absorb )(2)

(mg/kg day) '

86

86

Tumor site

Oral

Stomach

NA

Inhalation

NA

NA

LPA Carcmogenicity

Classification

B2

B2

Integrated Risk Information System (1RJS 2001) is the source of CSF Non carcinogenic toxicity criteria (RfDs or RfCs) are nol available for any of the COPCs all are considered potentially carcinogenic

and toxicity cntiena used in RBC calculations are Cancer Slope Factors (CSFs)

Adjusted oral CSF = (Oral CSF)/(Oral absorption efficiency) Oral absorption efficiency of PAHs = 0 85 (A fSDR 1990)

CSFi for benzo(a)pyrene is provisional

CSF = benzo(a)p>reneCSI~ modified by toMcityequi alenc> factor (USEPA 1993)

870361 ^33 AQ Page 1 of IFurnace Group RBC Report

December 2001

Table 3-1Exposure Assumptions

Furnace GroupAlcoa Davenport Works Riverdale Iowa

ParameterSoil ExposureAT (carcinogenic)AT (non carcinogenic)BRBWEDEFETPEFSARSIRSSAVF

(units)

(days/lifetime)(days/lifetime)(mVhr)(kg)(years)(days/year)(hours/day)(mVkg)(mg/cm2/day)(mg/day)(cm')(mVkg)

FrequentOn Site Worker

2555091252570251908

4 6 3 x 109 *00850

1 130*

OccasionalOn Site Worker

255509125257025388

463 x 109 *00850

1 130*

InfrequentOn Site Worker

255509 125257025198

4 63 x 109 *00850

1 130*

RepairWorker

255509125^25

702558

543x 107 *02100

4 100*

ConstructionWorker

255503652570

1608

543 x 106 *02100

4100*

* Based on equations in revisions to EPA s RAGS Part B (EPA 199la) VF is a chemical specific value and the default PEF value

is 4 63 x io9 m3/kg The construction worker PEF value is 5 43 x 106 m3/kg and the repair worker PEF value is 5 43 x 107 m3/kg

ATBRBWcm2

EDEFETkgm3/day

Averaging timeBreathing rateBody weightSquare centimetersExposure durationExposure frequencyExposure timeKilograms

Cubic meters per day

m3/hrm3/kgmg/daymg/cm2/dayPEFSARSIRSSA

VF

Cubic meters per hourCubic meters per kilogramMilligrams/dayMilligram per square centimeter per dayPaniculate emission factorSkin adherence rateSoil ingestion rateExposed skin surface area

Volatilization factor

Rev T 3 1 pel xls Page 1 of 1Furnace Group RBC Report

Rev May 2004

TaCTe3-2Exposure Point Concentrations for COPCs in Subsurface Soil

Furnace Group, Alcoa-Davenport Works, Riverdale, Iowa

Constituent ofPotential Concern

Benzo(a)pyrene

Dibenz(a h)anthracene

Sample Size

8

8

% Non detects

100

100

Max Detect(mg/kg)

ND

ND

Data SetDistribution

NA

NA

EPC StatisticalMethod

Min/Max SQL

Min/Max SQL

EPC1"

<0 34 <0 4

<0 34 <0 4

(1> EPC listed with <# <# denotes a detection limit range

ND = constituent not detected

NA = Not Applicable

870361 233 AQ Page 1 of 1Furnace Group RBC Report

December 2001

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Table 4 1Risk Based Concentration Equations For Soil Exposure Furnace Group Alcoa Davenport Works

Riverdale Iowa

where

a Alpha calculation intermediate (cmVsec)A Contiguous area of contamination (m2) (2 025 m2 [EPA 199 la default] or unit specific area)ABSd Dermal absorption efficiency (unitless) constituent specificATC Averaging period for cancer effects (days)ATNC Averaging period for non cancer effects (days) ED x 365 days/year (EPA 199la)BR Breathing rate (m3/hr)BW Body weight (kg)CSF Cancer slope factor for oral (CSF ) dermal (adjusted to an absorbed dose CSF ) or inhalation (CSF)

exposure (kg day/mg inverse of mg/kg/day)Dei Effective diffusivity (cmVsec)DH Diffusion height (2 m) (EPA 1991 a)Di Diffusivity m air (cmVsec) constituent specificED Exposure duration (years)EF Exposure frequency (days/year)ET Exposure time (hours/day)F Fraction organic carbon in soil (unitless) (0 02 EPA 1991a default)H Henry s Law Constant (atm mVmol) constituent specificK. Soil air partition coefficient (g soil/cm3 air)K.d Soil water partition coefficient (cm3/g or mL/g) constituent specific Kd is calculated as F x K,, (EPA

1991a)K Organic carbon partition coefficient (cm3/g or mL/g) constituent specificLS Length of side of contaminated area (m) (45m [EPA 1991 a default] or unit specific length)Pa Air filled soil porosity (unitless)Pt Total Soil Porosity (fraction unitless)p s True soil or particle density (2 65 g/cm3)(EPA 1991 a)RBC Risk based concentration for soil (mg/kg) minimum of the RBCC (based on cancer effects) and the

RBCNC (based on non cancer effects) which are based on the route specific RBCs (RBC for the oralroute RBCd for the dermal route and RBC for the inhalation route)

RfD Reference dose for oral (RfD ) dermal (adjusted to an absorbed dose RfDJ or inhalation (RfD)exposure (mg/kg/day)

RT Product of the ideal gas constant (8 206 x 10s atm m3/moI/K) and the Kelvin temperature (298 Kequivalent to 25 C) = 0 02445 atm m3/mol

SAR Skin adherence rate (mg/cm /day)SIR Ingestion rate of soil (mg/day)SSA Exposed skin surface area (cm2)T Exposure interval (7 9E+08 sec) (EPA 199la)TCR Target cancer risk (unitless) results presented for TCR values of 1x104 (1 in 10 000) and 1x106 (1 in

1 000 000)THI Target hazard index (unitless) results presented for THI value of 1V Wmdspeed in the mixing zone (2 25 m/sec) (EPA 199la)VF Volatilization factor (m3/kg)

Furnace Group RBC Report870361 233 AQ Page 2 of 3 December 2001

Table 4 1Risk Based Concentration Equations For Soil Exposure Furnace Group Alcoa Davenport Works

Riverdale Iowa

SAMPLE CALCULATION (Benzo(a)pyrene Excavation Repair Worker)

Cancer Effects

(10"6)x(70Ag) (25550<tow) ( I 0 6 m g / k g )(RBC ) = = !96mg/*g

°C (lOOmg/rfcrv) (5days/yr)x (25 vrs) (1 3 kg day / mg)

(10 ~6 ) x (70 kg) (25550 days) x (10 6 mg/kg)(RBCd )c = j -, = 203 mg/kg

(4100cm )x(02mg/cm ) x (0 10) x (5 days/yr) x (25 yrs) x (8 6 kg day/mg)

( 1 0 ~ 6 ) x (70kg) x (25550days)(RBC ) = = 8 4 7 5 m g / k g

[ (1 /1 13x 10 ) + (! / 5 4 3 x 10 ) ] x ( 2 5 m / hr) x (8hr / day) x (5days/yr) x (25 yrs) x (3 1kg day /mg)

RBCr = - = 10 mg / kgC 1 1 1

1 9 6 m g / k g 20 3 m g / k g 8 475 m g / k g

Non Cancer Effects

6( l )x (70kg) x (9125 da>s)x (10 mg/kg)

(RBC 0)N C = = NA( l O O m g / d a y ) x (5days /y r ) x (25yrs) x ( 1 / N A )

(I) (70kg) (9/2Jdays) (106 m g / k g )_ _ NA

(4100cm ) ( 0 2 m g / c m ) (010) (5days/yr) (25yrs) ( 1 / N A )

(1) x (70 kg) x (9 125 days)(RBC,)N C = - = NA

8 7 3[(1/1 13 x 10 ) + (1 7543 xlO )]x ( 2 5 m / hr) x (8hr / day) x (5 days/ yr) x (25 yrs) x ( l / N A )

NA NA NA

Minimum RBC

RBC = MINIMUM[(\ 0 mg I kg} ( NA)} = 1 0 mg I kg

Furnace Group RBC Report870361 233 AQ Page 3 of 3 December 2001

Table 4 2Risk Based Concentrations for Excavation Repair Worker Exposure to Soil

Furnace Group, Alcoa Davenport Works Riverdale Iowa

Constituent ofPotential Concern

(COPC)

Benzo(a)pyreneDibenz(a h)anthracene

POTENTIAL CANCER EFFECTS

Route Specific RBCs (TCR = 10s)(mg/kg)

Oral

196196

Dermal

20292029

Inhalation

847512 155

Comprehensive RBC(mg/kg)

TCR 10 6

1010

TCR 10 4

1 0001000

NON CANCER EFFECTS

Route Specific RBCs (HI=1)(mg/kg)

Oral

NANA

Dermal

NANA

Inhalation

NANA

Comprehensive

RBC

(mg/kg)

NANA

COPC Constituent of Potential Concern

RBC Rjsk Based ConcentrationTCR Target Cancer RiskHI Hazard IndexNA Not Applicablemg/kg Milligrams per kilogram

870361 233 AQ Page I of 1Furnace Group RBC Report

December 2001

Table 4 3Risk Based Concentrations for Excavation Construction Worker Exposure to Soil

Furnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent ofPotential Concern

(COPC)

Benzo(a)pyreneDibenz(a h)anthracene

POTENTIAL CANCER EFFECTS

Route Specific RBCs (TCR = 10 6)(mg/kg)

Oral

408408

Dermal

42274227

Inhalation

24912603

Comprehensive RBC(mg/kg)

TCR 10 6

2121

TCR 10 4

2 1002 100

NON CANCER EFFECTS

Route Specific RBCs (Hl=l)(mg/kg)

Oral

NANA

Dermal

NANA

Inhalation

NANA

ComprehensiveRBC

(mg/kg)

NANA

COPC Constituent of Potential ConcernRBC Risk Based ConcentrationTCR Target Cancer RiskHI Hazard IndexNA Not Applicablemg/kg Milligrams per kilogram

870361 233 AQ Page 1 of 1Furnace Group RBC Report

December 2001

Tamr4 4Comparison of Exposure Point Concentrations to Risk-Based Concentrations

Excavation Repair Worker Exposure to Subsurface SoilFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent of

Potential Concern

Benzo(a)pyrene

Dibenz(a h)anthracene

EPC

(mg/kg)

<034 <04

<034 <04

POTENTIAL CANCER EFFECTS RBC

(mg/kg)

TCR 10 6

10

10

TCR 10 4

1000

1000

NON CANCER

EFFECTS RBC

(mg/kg)

NA

NA

EPC > RBC

No

No

NA Not Applicable

87036J 233 AQ Page 1 of 1Furnace Group RBC Report

December 2001

raW4Comparison of Exposure Point Concentrations to Risk-Based Concentrations

Excavation Construction Worker Exposure to Subsurface SoilFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent of

Potential Concern

Benzo(a)pyrene

Dibenz(a h)anthracene

EPC(mg/kg)

<034 <04

<034 <04

POTENTIAL CANCER EFFECTS RBC

(mg/kg)

TCR106

21

21

TCR 10 4

2100

2100

NON CANCER

EFFECTS RBC

(mg/kg)

NA

NA

EPC > RBC

No

No

NA Not Applicable

870361 233 AQ Page 1 of 1Furnace Group RBC Report

December 2001

Table 4-6Comparison of Exposure Point Concentrations to Risk Based Concentrations

Frequent On Site Worker ScenarioFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent of II EPCPotential Concern (mg/kg)

(COPC) 1

Benzo(a)pyreneDibenz(a h)anthracene

<034 <04<0 34 - <0 4

POTENTIAL CANCER EFFECTS RBC(mg/kg)

TCR 10"6

087087

TCR 10^

8787

NON CANCEREFFECTS RBC

(mg/kg)

NANA

EPC > RBC

No [a,b]No [a,b]

[a] Insufficient toxicity information exists for this constituent therefore some or all of the RBC values (as indicated) cannot be calculated and compared to the EPCs

[b] Constituent was not detected but was included as a COPC because 20 percent or more of the SQLs exceeded the regulatory benchmark

COPC Constituent of Potential Concern

EPC Exposure Point Concentration

RBC Risk Based Concentration

TCR Target Cancer Risk

NA Not Applicable

mg/kg Milligrams per kilogram

Rev T 4 6 pel xls Page 1 of 1Furnace Group RBC Report

Rev May 2004

Table 4-7Comparison of Exposure Point Concentrations to Risk Based Concentrations

Occasional On-Site Worker ScenarioFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent ofPotential Concern

(COPC)

Benzo(a)pyrene

Dibenz(a h)anthracene

EPC(mg/kg)

<034 <04<034 <04

POTENTIAL CANCER EFFECTS RBC

(mg/kg)

TCR 10"6

4444

TCR 10"4

440440

NON CANCER

EFFECTS RBC

(mg/kg)

NANA

EPC > RBC

No [a b]No [a,b]

[a] Insufficient toxicity information exists for this constituent therefore some or all of the RBC values (as indicated) cannot be calculated and compared to the EPCs

[b] Constituent was not detected but was included as a COPC because 20 percent or more of the SQLs exceeded the regulatory benchmark

COPC Constituent of Potential ConcernEPC Exposure Point ConcentrationRBC Risk Based Concentration

TCR Target Cancer Risk

NA Not Applicable

mg/kg Milligrams per kilogram

Rev T 4 7 pel xls Page 1 of 1Furnace Group RBC Report

Rev May 2004

Table 4-8Comparison of Exposure Point Concentrations to Risk Based Concentrations

Infrequent On-Site Worker ScenarioFurnace Group, Alcoa Davenport Works, Riverdale, Iowa

Constituent ofPotential Concern

(COPC)

Benzo(a)pyreneDibenz(a h)anthracene

EPC(mg/kg)

<034 <04<034 <04

POTENTIAL CANCER EFFECTS RBC(mg/kg)

TCR 10"6

8787

TCR 10"4

870870

NON CANCEREFFECTS RBC

(mg/kg)

NANA

EPC > RBC

No [a b]No [a,b]

[a] Insufficient toxicity information exists for this constituent therefore some or all of the RBC values (as indicated) cannot be calculated and compared to the EPCs

[b] Constituent was not detected but was included as a COPC because 20 percent or more of the SQLs exceeded the regulatory benchmark

COPC Constituent of Potential Concern

EPC Exposure Point Concentration

RBC Risk Based Concentration

TCR Target Cancer Risk

NA Not Applicable

mg/kg Milligrams per kilogram

RevT-48pclxls Page 1 of 1Furnace Group RBC Report

Rev May 2004

Source U S G S Topographic Map

Silvis III Iowa Quadrangle 41090 E4 TF 024 1991

Scale 1 =2000

IT CorporationLocation and Physical

Setting of Alcoa Davenport WorksRiverdale Iowa

870*61 23 AQ

NPOESOutf 11006

SCALEfeet

1000

PLANTNORTH N

Furnace Unit Group

IPO 04 50 Inch Continuous HeatTreatment Line(Former Paint Line Location)

IPO 05 Ingot Plant Melting Furnacesand Casting Pits

IPO 08 Soaking PitsIPH 09 No 8 and No 9 Vertical Heat

Treatment Furnaces

Industrial Process Units (IP)

NPDES Outfall

Figure 2-1

H IT CorporationFurnace Group RBC Report

Location of FSA UnitsAlcoa Davenport Works Riverdale Iowa

870361 233 AQ

ooo

»-? 2t v

18

"ID " P

JOB ND. 7036110600 PLOT SCALE 1=1

STARTED ON 9/29/98 REVISED 12/17/01

S-3PWKING UIT

S-4ARH1MC L£7T

900

904

816

816

(lPO-04) 816

906 907

915

926SOK-HA01

SOK-HA02\

925

(lPH-09')925

SOK-HA04909 SOK-HA05

SOK-HA06

902

912

912

905911A

910

814

814 Qpo-osr

616-HA02 » 810-HAO1

/SOK-HA03

806 805

830

400

ir

LEGEND

J INDUSTRIAL PROCESS UNITS

• SOIL SAMPLE (GRAB) LOCATION

A SOIL SAMPLE (COMPOSITE) LOCATION

IPO-04 50-INCH CONTINUOUS HEAT TREATMENT LINE(FORMER PAINT LINE LOCATION)

IPO-05 INGOT PLANT WELTING FURNACES ANDCASTING PITS

IPO-08 SOAKING PITSIPH-09 NO 8 AND NO 9 VERTICAL HEAT

TREATMENT FURNACES

ALCOA - DAVENPORT WORKSRIVEROALE IOWA

IT orationPITTSBURGH PA

FIGURE 2-2

LOCATION OF SOIL SAMPLESAT THE FURNACE GROUP

DATE 12/17/01

SCALE AS NOTED

DR M WILLIAMS

DWG NO 20153011

PRIMARY PRIMARY SECONDARY SECONDARY TRANSPORTSOURCE RELEASE SOURCE RELEASE MEDIUM

MECHANISM MECHANISM

1 1 N N i 1 rIndustrial \ . Subsurface \ fr- Subsurface pPron-srng Leaks / > Sn.l Leaching > ^ So.'

I/ ' ' ' V' V

Pathways addressed in this report

Pathways addressed m subsequent reports_^^_^

Ground water k

r\ L ourraco .„ , r— z ' \ " water '

^ Releases to ^ „ ^ \— ̂ Storm Sower-- "^ Treatment ^ Releases \_

Surface Water /

\/ k "wateT kp vvnux p

N.

EXPOSUREPOINT

Subsurface kSoil

_ _

Ground water k.

ExposureRoute On i

Wor

Ingestion

DermalContact

Inhalation

Exposure Menu

Human

;i,e Excavation Worker

ker Construction RepairWorker Worker

Biotad)

X X

X X

X X

— _

No receptors to Groundwater

To be addressedRBC Report

n the Outfalls Unit Group

River ' To be addressedMississippi River

\""/" F *JW*4II|1WII» | p^ Sediment | ^

/NOTES l̂

( 1 ) No ecological habitat has beenidentified at the Unit Group ecologicalrisk evaluation will not be performed

PJ.S Unit C

AI_COA orpora ion ALC(

To be addressedMississippi Riverthe Outfalls Unit

in the risk assessment forPool 15 (MRP15)

in the risk assessment forPool 15 (MRP15)andGroup RBC Report

Figure 2 3

onceptual Model for Potential ExposureFurnace Unit Group

DA Davenport Works River dale Iowa870361 233 AQ

APPENDIX A

ANALYTICAL DATA

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUN1T

SAMPLE DATEPARAMETER

Volatiles1 2 Tetrachloroethane1 Tnchloroethane2 2 Tetrachloroethane2 TnchloroethaneDichloroe thaneDichloroethene

1 Dichloropropene2 3 Tnchloropropane2 Dibromo 3-chloropropane2 Dibromoethane2 Dichloroethane

1 2 Dichloroethene (Total)1 2 Dichloropropane1 3 Dichloropropane2 2 Dichloropropane2 HexanoneAcetoneBenzeneBromobenzeneBromochloromethaneBromodichloromethaneBromoform3romomelhaneCarbon disulfldeCarbon tetrachlondeChlorobenzeneChloroethane

B 17 8 5

Grab R1PO-04

9/6/1991

NANANANANANANANANANANANANANANANANANANANAMANANANANANANA

B 23 5

Grab R1PO-04

9/6/1991

NA0006U

NA0006U0006U0006U

NANANANA

0006U0006U0006U

NANA

001 U001 U

0006UNANA

0006U0006U001 U0006U0006U0006U0 0 1 U

SDK HA010 1

Grab R1PO-08

10/9/1997

NA00061U00061U0 0061 U00061U0 0061 U

NANANANA

0 0061 U0 0061 U0 0061 U

NANA

0024U0069J

0 0061 UNANA

00061U0 0061 U0012U

0 0061 U0 0061 U00061 U0012U

SOK HA024 5

Grab RIPO-08

10/9/1997

NA00051U00051U00051U00051U00051U

NANANANA

00051 U00051 U00051U

NANA

002UJ002UJ

00051 UNANA

00051U00051U001U

00051 U00051U00051U

001 U

SOK HA030 1

Grab RIPO-08

10/9/1997

NA0006U0006U0006U0006U0006U

NANANANA

0006U0006U0006U

NANA

0024U0 024 UJ0006U

NANA

0006U0006U0012U0006U0006U0006U0012U

SOK HA040 1

Grab RIPO 08

10/9/1997

NA0 0057 U0 0057 U0 0057 U0 0057 U0 0057 U

NANANANA

0 0057 U0 0057 U0 0057 U

NANA

0 023 UJ0 023 UJ0 0057 U

NANA

0 0057 U0 0057 U0011 U

0 0057 U00057U0 0057 U0011 U

SOK HA053-4

Grab RIPO-08

10/9/1997

NA0 0058 U00058U0 0058 U00058U0 0058 U

NANANANA

0 0058 U00058U0 0058 U

NANA

0 023 UJ0 023 UJ00058U

NANA

0 0058 U0 0058 U0012U

00058U0 0058 U0 0058 U0012U

SOK HA06*0 1

Grab RIPO 08

10/9/1997

NA00058U00058U0 0058 U0 0058 U00058U

NANANANA

0 0058 U0 0058 U0 0058 U

NANA

0 023 UJ0 023 UJ0 0058 U

NANA

0 0058 U0 0058 U0012U

00058U0 0058 U0 0058 U0 0 1 2 U

RevTA I pel xls A 1 1Furnace Croup RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETERChloroformChloromethanecis 1 2 Dichloroethenecis 1 3 DichloropropeneCylcohexane 1 Methyl-4DibromochloromethaneDibromomethaneDichlorodifluoromethaneElhylbenzeneIsopropylbenzeneMethyl ethyl ketoneMethyl isobutyl ketoneMethylene chloriden Butylbenzenen Propylbenzenep Isopropyltoluenesec ButylbenzeneStyrenetert ButylbenzeneTetrachloroetheneToluenetrans 1 2 Dichloroethenetrans 1 3 DichloropropeneTnchloroetheneTnchlorofluoromethanernchlorotnfluoroe thaneVinyl acetateVinyl chlorideXylenes Total

B 17 8 5

Grab RIPO-04

9/6/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

B 235

Grab R.IPO-04

9/6/1991

0006U001 U

NA0006U

NA0006U

NANA

0006UNA028

001 U0006U

NANANANA

0006UNA

0006U0006U

NA0006U0006U

NANA

0 0 1 U001 U

0006U

SDK HA010 1

Grab R1PO-08

10/9/1997

0 0061 U0012U

NA0 0061 U

NA0 0061 U

NANA

0 0061 UNA

0 024 UJ0 024 UJ0 0061 U

NANANANA

00061UNA

000310 0061 U

NA0 0061 U0 0061 U

NANANA

0012U00061U

SOK HA024-5

Grab RIPO-08

10/9/1997

00051 U001 U

NA00051 U

NA00051U

NANA

00051 UNA

002UJ002U

00051 UNANANANA

00051 UNA

00051U00051U

NA00051U00051 U

NANANA

001U00051U

SOK HA030 1

Grab RIPO-08

10/9/1997

0006U0012U

NA0006U

NA0006U

NANA

0006UNA

0 024 UJ0 024 UJ0006U

NANANANA

0006UNA

0006U0006U

NA0006U0006U

NANANA

0012U0006U

SOKHA040 1

Grab RIPO-08

10/9/1997

0 0057 U0011U

NA0 0057 U

NA0 0057 U

NANA

0 0057 UNA

0 023 UJ0023U0 0057 U

NANANANA

0 0057 UNA

0 0057 U0 0057 U

NA0 0057 U0 0057 U

NANANA

0011U0 0057 U

SOK HA053-4

Grab RIPO 08

10/9/1997

0 0058 U0012U

NA0 0058 U

NA0 0058 U

NANA

0 0058 UNA

0 023 UJ0023U0 0058 U

NANANANA

0 0058 UNA

0 0058 U0 0058 U

NA00058U00058U

NANANA

0012U0 0058 U

SOK. HA06*0 1

Grab RIPO-08

10/9/1997

0 0058 U0 0 1 2 U

NA00058U

NA0 0058 U

NANA

0 0058 UNA

0 023 UJ0023U0 0058 U

NANANANA

0 0058 UNA

0 0058 U00058U

NA0 0058 U00058U

NANANA

0012U00058U

RevT A 1 pel xls A 1 2Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETER

Semivola tiles2 3 Trichlorobenzene2 4 Trichlorobenzene2 4 Trimethylbenzene

1 2 Dichlorobenzene3 5 Trimethylbenzene3 Dichlorobenzene4 Dichlorobenzene

245 Trichlorophenol246 Trichlorophenol2 4 Dichlorophenol2 4 Dimethylphenol2 4 Dmitrophenol2 4 Dmitrotoluene2 6 Dmitrotoluene2-Chlorophenol2-Chlorotoluene2 Methyl-4 6-dimtrophenol2 Methylnaphthalene2 Methylphenol2 Nitroanilme2 Nitrophenol3 3 Dichlorobenzidine

3 Nitroanilme4 6 Dimtro 2 methyl phenol4 Bromophenyl phenyl ether4-Chloro 3 methylphenol4-Chloroanilme4-Chlorophenyl phenyl ether4-Chlorotoluene4 Methylphenol4 Nitroanilme4 NitrophenolAcenaphtheneAcenaphthyleneAnthracene

B 17 8 5

Grab R1PO-04

9/6/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

B 23 5

Grab RIPO 04

9/6/1991

NANANANANANANANANANANANANAMANANANANANANANANANANANANANANANANANANANANANA

SDK HA010 1

Grab R.IPO-08

10/9/1997

NA0 4 UNA

0 4 UNA

0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U19U0 4 U0 4 U0 4 UNANA

0 4 U0 4 U1 9U0 4 U1 9U1 9 U19U0 4 U0 4 U0 4 U0 4 UNA

0 4 U1 9 U1 9 U0 4 U0 4 U0 4 U

SOK HA024 5

Grab RIPO-08

10/9/1997

NA034U

NA034U

NA034U034U034U034U034U034U1 6U

034U034U034U

NANA

034U034U1 6 U

034U1 6 U1 6 U16U

034U0 3 4 U034U034U

NA034U1 6 U1 6 U

034U034U034U

SOK HA030 1

Grab RIPO-08

10/9/1997

NA039U

NA039U

NA039U039U039U039U039U039U1 9 U

039U039U039U

NANA

039U039U19U

039U1 9U1 9 U1 9 U

039U039U039U039U

NA039U19U1 9 U

039U039U039U

SOK HAM0 1

Grab RIPO-08

10/9/1997

NA038U

NA038U

NA038U038U038U038U038U038U1 8 U

038U038U038U

NANA

038U038U1 8 U

038U1 8 U1 8 U1 8U

038U038U038U038U

NA038U1 8 U1 8 U

038U038U038U

SOK HA053-4

Grab RIPO-08

10/9/1997

NA038U

NA038U

NA038U038U038U038U038U038U1 9 U

038U038U0 3 8 U

NANA

038U038U1 9U

038U1 9U1 9 U1 9 U

038U0 3 8 U038U038U

NA0 3 8 U1 9 U1 9 U

038U038U038U

SOK HA06*0 1

Grab RIPO 08

10/9/1997

NA038U

NA038U

NA038U038U038U038U038U038U1 9 U

038U038U038U

NANA

038U038 U1 9 U

038U1 9U1 9 U1 9 U

038U038U038U038U

NA038U1 9 U1 9 U

038U038U0 3 8 U

RevT A 1 pel xls A 1 3Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETERBenzidmeBenzo(a)anthraceneBenzo(a)pyreneBenzo(b)fluorantheneBenzo(g h i)peryleneBenzo(k)fluorantheneBenzoic AcidBenzyl alcoholBenzyl butyl phthalatebeta-Chloronaphthalenebis(2-Chloroethoxy)methanebis(2-Chloroethyl)etherBis(2chloroisopropyl)etherbis(2-Chloroisopropyl)etherbis(2 Ethylhexyl)phthalateButyl benzyl phthalateCarbazoleChryseneCresols TotalDibenz(a,h)amhraceneDibenzofuranDibutyl phthalateDiethyl phthalateDimethyl phthalateDi n-octyl phthalateFluorantheneFluoreneHexachloro-1 3 butadieneHexachlorobenzenehiexachlorobutadieneHexachlorocyclopentadieneHexachloroe thaneIndeno(l 2,3 cd)pyrene

B 17 8 5

Grab RIPO 04

9/6/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

B 23 5

Grab RIPO-04

9/6/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

SDK HA010 1

Grab RIPO-08

10/9/1997

NA0 4 U0 4 U0 4 U0 4 U0 4 UNANANA

0 4 U0 4 U0 4 UNA

0 4 U0 4 U0 4 U0 4 U0 4 UNA

0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 UNA

0 4 U0 4 U1 9 U0 4 U0 4 U

SDK HA024 5

Grab RIPO-08

10/9/1997

NA034U034U034U034U034U

NANANA

034U034U034U

NA034U034U034U034U034U

NA034U034U034U034U034U034U034U034U

NA034U034U1 6 U

034U034U

SOK HA030 1

Grab RIPO-08

10/9/1997

NA039U039U039U039U039U

NANANA

039U039U039U

NA039U039U039U039U039U

NA039U039U039U039U039U039U039U039U

NA039U039U1 9 U

039U039U

SOKHA040 1

Grab RIPO-08

10/9/1997

NA038U0 3 8 U038U038U038U

NANANA

038U0 3 8 U038U

NA038U038U038U038U038U

NA038U038U038U038U038U038U038U038U

NA038U038U1 8U

038U038U

SOK HA053-4

Grab RIPO-08

10/9/1997

NA038U038U038U038U038U

NANANA

038U038U038U

NA038U038U038U038U038U

NA038U0 3 8 U038U038U038U038U038U038U

NA038U038U1 9U

038U038U

SOK HA06*0 1

Grab RIPO 08

10/9/1997

NA038U038U038U038U038U

NANANA

038U038U038U

NA0 3 8 U038U038U038U038U

NA038U038U038U038U038U038U038U0 3 8 U

NA038U038U1 9 U

038U038U

RevT A 1 pel xls A 1-4Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE OEPTH(ft)

SAMPLE TYPEFSA UNIT

SAMPLE DATEPARAMETERIsophoroneNaphthaleneNitrobenzeneN Nitroso di n propylammeN NitrosodimethylamineN NitrosodiphenylammePentachlorophenolPhenanthrenePhenolPyrenePyndme

AroclorsAroclor 1016/1242Aroclor 1016

Aroclor 1221Aroclor 1232

Aroclor 1242Aroclor 1248

Aroclor 1254Aroclor 1260

Aroclor 1268Miscellaneous

Total Extractable HydrocarbonsDieselMotor OilGasolineFPH Gasoline Non Aqueous

B 17 8 5

Grab RIPO 04

9/6/1991

NANANANANANANANANANANA

NA002U002U002U002U

0250 0 2 U002U

NA

NANANANANA

B 23 5

Grab RIPO-04

9/6/1991

NANANANANANANANANANANA

NA002U002U002U002U025

002U0 0 2 U

NA

NANANANANA

SOK HA0101

Grab RIPO-08

10/9/1997

0 4 U0 4 U0 4 U0 4 UNA

0 4 U1 9 U0 4 U0 4 U0 4 UNA

NA002U002U002U002U0098004U004U

NA

NANANANANA

SOK HA024 5

Grab R1PO-08

10/9/1997

034U034U034U034U

NA034U16U

034U034U034U

NA

NA0017U0017U0017U0017U0017U0034U0034U

NA

NANANANANA

SOK HA030 1

Grab RIPO-08

10/9/1997

039U039U039U039U

NA039U1 9 U

039U039U039U

NA

NA002U002U002U002U002U004U004U

NA

NANANANANA

SOKHA040 1

Grab RIPO-08

10/9/1997

038U038U038U038U

NA038U1 8 U

038U038U038U

NA

NA0019U0019U0019U0019U0019U0038U0038U

NA

NANANANANA

SOK HA053-4

Grab RIPO 08

10/9/1997

038U038U038U038U

NA038 U1 9U

038U038U038U

NA

NA0019U0019U0019U0019U0019U0039U0039U

NA

NANANANANA

SOK HA06*0 1

Grab RIPO 08

10/9/1997

038U038U038U038U

NA038U1 9U

038U038U038U

NA

NA0019U0019U0019U0019U0019U0039U0039U

NA

NANANANANA

NotesComp = Composite sampleR = RandomB = BiasedU = Not detected at indicated detection limitJ = Estimated value

NA = Not analyzedAll units are mg/kg unless noted otherwise*SOK HA06 is a field duplicate of SOK HA04

RevTA 1 pclxls A 1 5Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Croup

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETER

Voladles1 1 1 2 Tetrachloroethane1 1 1 Tnchloroethane

1 2 2 Tetrachloroethane1 2 Tnchloroethane1 Dichloroethane1 Dichloroethene1 Dichloropropene2 3 Tnchloropropane2 Dibromo-3-chloropropane2 Dibromoethane2 Dichloroethane2 Dichloroethene (Total)2 Dichloropropane3 Dichloropropane

2 2 Dichloropropane2 HexanoneAcetoneBenzeneBromobenzeneBromochloromethaneBromodichloromethaneBromoformBromomethaneCarbon disulfideCarbon tetrachlondeChlorobenzeneChloroethane

TB913

Trip Blank

9/13/1991

NA10Uug/llOUug/110Uug/llOUug/1lOUug/1

NANANANA

10Uug/l10Uug/l10Uug/l

NANA

10Uug/llOUug/110Uug/l

NANA

lOUug/110Uug/llOUug/15 Jug/1

10Uug/l10Uug/l10Uug/l

TB91191

Tnp Blank

9/11/1991

NA10Uug/llOUug/110Uug/I10Uug/l10Uug/l

NANANANA

lOUug/l10Uug/l10Uug/l

NANA

10Uug/l10Uug/l10Uug/l

NANA

10Uug/l10Uug/l10Uug/l10Uug/l10Uug/l10Uug/l10Uug/l

VMX1S3 5

Comp BIPO-04

9/1 1/1991

NA0012U0012U0012U0012U0012U

NANANANA

0012U0012U0012U

NANA

0012U0051

0012UNANA

0012U0012U0012U0012U0012U0012U0012U

VMX2S35

Comp BIPO-04

9/1 1/1991

NA0012U0012U0012U0012U0012U

NANANANA

0012U0012U0012U

NANA

0012U0008J0012U

NANA

0012U0012U0012U0012U0012U0012U0012U

VMX3S35

Comp BIPO-04

9/11/1991

NA0012U0012U0012U0012U0012U

NANANANA

0012U0012U0012U

NANA

0005J015

0012UNANA

0012U0012U0012U0012U0012U0012U0012U

810HA015-6

Grab R1PO-05

11/18/1998

0005U0005U0005U0005U0005U0005U0005U0005U005U005U

0005UNA

0005U0005U0005U

NANA

0005U0005U0005U0005U001 U002U

NA0005U0005U0 0 2 U

810HA023^»

Grab RIPO 05

11/18/1998

0005U0005U0005U0005U0005U0005U0005U0005U005U0 0 5 U

0005UNA

0005U0005U0005U

NANA

0005U0005U0005U0005U001 U002U

NA0005U0005U0 0 2 U

810HA030 1 33

Grab RIPO 05

11/18/1998

0005 U0005U0005U0005U0005U0005 U0005U0005U0 0 5 U0 0 5 U

0005UNA

0005U0005U0005U

NANA

0005U0005 U0005U0005U001 U002U

NA0005U0005U0 0 2 U

RevT A 1 pel xls A 1-6Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSA UNIT

SAMPLE DATEPARAMETER

ChloroformChloromethanecis 1 2 Dichloroethenecis 1 3 DichloropropeneCylcohexane 1 Methyl-4DibromochloromethaneDibromomethaneDichlorodifluoromethaneEthylbenzeneIsopropylbenzeneMethyl ethyl ketoneMethyl isobutyl ketoneMethylene chloriden Butylbenzenen Propylbenzenep Lsopropyltoluenesec ButylbenzeneStyreneten ButylbenzeneretrachloroetheneToluenetrans 1 2 Dichloroethenetrans 1 3 DichloropropeneFnchloroetheneTnchlorofluoromethanernchlorotrifluoroe thaneVinyl acetateVinyl chlorideXylenes Total

TB9 13

Trip Blank

9/13/1991

10Uug/l10Uug/l

NAlOUug/1

NA10Uug/l

NANA

10Uug/lNA

10Uug/l10Uug/l10Uug/l

NANANANA

10Uug/lNA

10 U ug/110Uug/l

NA10Uug/l3 Jug/1

NANANA

10Uug/l10Uug/l

TB91191

Tnp Blank

9/11/1991

10Uug/l10Uug/l

NA10Uug/l

NA10Uug/l

NANA

10Uug/lNA

lOUug/110Uug/l10Uug/l

NANANANA

10Uug/lNA

10 U ug/110Uug/l

NA10 U ug/110 U ug/1

NA20 Jug/1

NA10 U ug/110 U ug/1

VMX1S3 5

Comp BIPO-04

9/11/1991

0012U0012U

NA0012U007J

0012UNANA

0012UNA

0009J0012U0006J

NANANANA

0012UNA

0012U0012U

NA0012U0004J

NANANA

0012U0012U

VMX2S35

Comp BIPO-04

9/11/1991

0012U0012U

NA0012U

NA0012U

NANA

0012UNA

0003J0012U0012U

NANANANA

0012UNA

0004J0012U

NA0012U0004J

NANANA

0012U0012U

VMX3S3 5

Comp BIPO-04

9/11/1991

0012U0012U

NA0012U

NA0012U

NANA

0012UNA

00390012U0006J

NANANANA

0012UNA

0012U0005J

NA0012U0004J

NANANA

0012U0012U

810HA0156

Grab RIPO-05

11/18/1998

0005U002U

0005U0005U

NA0005U0005U0015U0005U0005U

NANA

005U0005U0005U0005U0005U0005U0005U0005U0005U0005U0005U0005U002U

NANA

0015U0005U

810HA023^t

Grab RIPO 05

11/18/1998

0005U002U

0005U0005U

NA0005U0005U0015U0005U0005U

NANA

0 0 5 U0005U0005U0005U0005U0005U0005U0005U0005U0005U0005U0005U0 0 2 U

NANA

0015U0005U

810HA030 133

Grab RIPO-05

11/18/1998

0005U0 0 2 U

0005U0005U

NA0005U0005U0 0 1 5 U0005U0005U

NANA

005U0005U0005U0005U0005U0005U0005U0005U0005U0005U0005U0005 U0 0 2 U

NANA

0015U0005U

RevT A 1 pel xls A 1 7Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETER

Semivola tiles2 3 Tnchlorobenzene2 4 Tnchlorobenzene2 4 Tnmethylbenzene2 Dichlorobenzene3 5 Tnmethylbenzene3 Dichlorobenzene4 Dichlorobenzene

245 Trichlorophenol246 Tnchlorophenol2 4 Dichlorophenol2 4 Dimethylphenol2 4 Dimtrophenol2 4 Dmitrotoluene2 6 Dmitrotoluene2-Chlorophenol2-Chlorotoluene2 Methyl-4 6-dmitrophenol2 Methylnaphthalene2 Methylphenol2 Nitroamlme2 Nitrophenol3 3 Dichlorobenzidme3 Nitroaniline4 6 Dmitro 2 methylphenol4 Bromophenyl phenyl ether4-Chloro 3 methylphenol4-Chloroanilme4-Chlorophenyl phenyl ether4-Chlorotoluene4 Methylphenol4 Nitroanilme4 NitrophenolAcenaphtheneAcenaphthyleneAnthracene

TB9 13

Trip Blank

9/13/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

TB91191

Trip Blank

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

VMXIS3 5

Comp B1PO-04

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

VMX2S35

Comp B1PO-04

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

VMX3S3 5

Comp BIPO-04

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

810HA015-6

Grab RIPO 05

11/18/1998

0025U0025U0005U0005U0005U0005U0005U0 4 U04110 4 U0 4 U0 4 U0 4 U0 4 U0 4 U

0005U0 4 U0 4 UNA

0 4 U0 4 U0 4 U0 4 UNA

0 4 U0 4 U0 4 U0 4 U

0005UNA

0 4 U0 4 U0 4 U0 4 U0 4 U

810HA0214

Grab RIPO-05

11/18/1998

0025U0025U0005U0005U0005U0005U0005U036U036U036U036U036U036U036U036U0005U0 3 6 U036U

NA036U036U036U036U

NA036U036U036U036U

0005UNA

036U036U036U036U036U

810HA030133

Grab RIPO 05

11/18/1998

0025U0025U0005U0005U0005U0005U0005U036U0 3 6 U036U036U036U036U036U036U0005U036U036U

NA036U036U036U036U

NA036U036U0 3 6 U036U

0005UNA

036U0 3 6 U036U036U036U

RevTA 1 pclxls A 1 8Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Sod Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETER

Benzidinc3enzo(a)anthraceneBenzo(a)pyreneBenzo(b)fluoranthene3enzo(g h OperyleneBenzo(k)fluorantheneBenzoic AcidBenzyl alcoholBenzyl butyl phthalatebeta Chloronaphthalenebis(2 Chloroethoxy)methanebis(2-Chloroethyl)etherBis(2chloroisopropyl)etherbis(2-Chloroisopropyl)etherbis(2 EthylhexyOphthalateButyl benzyl phthalateCarbazoleChryseneCresols TotalDibenz(a,h)anthraceneDibenzofuranOibutyl phthalateDiethyl phthalateDimethyl phthalateDi n-octyl phthalate-luorantheneFluoreneHexachloro 1 3 butadieneHexachlorobenzeneHexachlorobutadiene-lexachlorocyclopentadieneHexachloroe thanendeno(l 2 3-cd)pyrene

TB9 13

Trip Blank

9/13/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

TB91191

Trip Blank

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

VMX1S35

Comp BIPO-04

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

VMX2S3 5

Comp BIPO-04

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

VMX3S3 5

Comp BIPO 04

9/11/1991

NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

810HA015-6

Grab RIPO 05

11/18/1998

4 U0 4 U0 4 U0 4 U0 4 U04U

079U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 UNA

0 4 UNANA

0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U

0025U079U0 4 U0 4 U

810HA023-4

Grab RIPO 05

11/18/1998

3 6 U036U036U036U036U036U0 7 3 U036U036U036U036U036U036U

NA036U

NANA

036U036U036U036U036U036U036U036U036U036U036U036U

0025U0 7 3 U036U036U

810HA030 133

Grab R1PO-05

11/18/1998

3 6 U036U036U036U036U036U0 7 3 U036U036U036U036U036U036U

NA036U

NANA

036U036U036U036U036U036U036U036U0 3 6 U036U036U036U

0025U073U036U036U

RevTA 1 pel xls A 1 9Furnace Group RBC Report

Rev May 2004

Table A 1Furnace Unit Group

Soil Analytical Results of Samples Included in the Risk AssessmentAlcoa Davenport Works

SAMPLE IDSAMPLE DEPTH(ft)

SAMPLE TYPEFSAUNIT

SAMPLE DATEPARAMETER

isophoroneNaphthaleneNitrobenzene

N Nitroso di n propylammeN NitrosodimethylammeN NitrosodiphenylammePentachlorophenolPhenanthrenePhenolPyrenePyridme

AroclorsAroclor 1016/1242Aroclor 1016Aroclor 1221Aroclor 1232Aroclor 1242Aroclor 1248Aroclor 1254Aroclor 1260Aroclor 1268

MiscellaneousTotal Extractable HydrocarbonsDieselMotor OilGasolineFPH Gasoline Non Aqueous

TB9 13

Tnp Blank

9/13/1991

NANANANANANANANANANANA

NANANANANANANANANA

NANANANANA

TB91191

Tnp Blank

9/11/1991

NANANANANANANANANANANA

NANANANANANANANANA

NANANANANA

VMX1S35

Comp B1PO-04

9/11/1991

NANANANANANANANANANANA

NA0041U0083U0041U0041U0041 U0041 U0041U

NA

NANANANANA

VMX2S35

Comp B1PO-04

9/11/1991

NANANANANANANANANANANA

NA0039U0080U0039U0039U0039U0039U0039U

NA

NANANANANA

VMX3S35

Comp B1PO-04

9/11/1991

NANANANANANANANANANANA

NA0040U0082U0040U0040U0040U0040U0040U

NA

NANANANANA

810HA015-6

Grab R1PO-05

11/18/1998

04U0025U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U0 4 U

0 5 UNA

0 5 U0 5 UNA

0 5 U0 5 U05UO S U

10 U10U10 U10U10U

810HA023-4

Grab RIPO 05

11/18/1998

036U0025U0 3 6 U036U036U036U036U036U036U036U036U

O S UNA

O S UO S UNA

O S UO S UO S UO S U

10 U10U10U10U10U

810HA030 133

Grab RIPO 05

11/18/1998

036U0025U036U0 3 6 U036U036U0 3 6 U036U036U036U0 3 6 U

O S UNA

O S UO S UNA071

O S UO S UO S U

10 U10U10U10 U10U

NotesComp = Composite sampleR = RandomB = BiasedU = Not detected at indicated detection limitJ = Estimated valueNA = Not analyzed

All units are mg/kg unless noted otherwise*SOK HA06 is a field duplicate of SDK HA04

RevT A 1 pel xls A 1 10Furnace Group RBC Report

Rev May 2004

APPENDIX B

UNIT RECOMMENDATION MEMOFURNACE GROUP

FSA UNITS IPO-04, IPO-05, IPO-08 and IPH-09May 2004

10 RECOMMENDATION

Alcoa recommends no further action for surface/subsurface soil at the Furnace Group under the 1995

Administrative Order of Consent (AOC) Docket No VII 95 F 0026 Details of the evaluation that led to

the recommendation are summarized in Table B 1 The table summarizes the recommendation for each

applicable scenano considered in the evaluation of the unit

The Furnace Group illustrated in Figure 2 1 was formed because each unit in the group is located in the

central area of the mam plant structure and each unit uses heat as part of the industrial process Also

each unit consists of heavy machinery or furnaces in buildings where there is no routine access to

subsurface soil Therefore similar exposure scenarios are appropriate at each unit m the grouping The

appropriate receptors selected for evaluation at this Unit Group are the excavation repair worker and the

excavation construction worker This RBC Report evaluates the potential risks associated with exposure

to COPCs in surface/subsurface soil Potential risks associated with constituents in the river will be

addressed in the Human Health Risk Assessment Report for Mississippi River Pool 15 Potential risks to

ecological receptors are not evaluated in this risk assessment because there is no ecological habitat at this

unit group

The constituents benzo(a)pyrene and dibenz(a h)anthracene were identified as COPCs in

surface/subsurface soil Non cancer RBCs for benzo(a)pyrene and dibenz(a,h)anthracene were not

calculated because the EPA verified RfD levels for these constituents are unavailable However both

EPCs were below comprehensive RBCs of the excavation repair worker and the excavation construction

worker reflecting a TCR of 10"6 Therefore no further action is warranted for surface/subsurface soils to

protect human health

Short term management plans are intended to manage those units where a change in Alcoa use or

development of the unit for other industrial purposes could result in a future risk to workers Short term

management plans are also proposed for those units where data are lacking to make an accurate

determination of future risk The EPCs of the COPCs (which were not detected) did not exceed the RBCs

for any current or future potential receptor However unit IPH 09 will be identified in the Plant s Short

Term Management Plan (STMP) as a unit where data are lacking The listing of this unit in the STMP

may be withdrawn in the future if data are collected that show there are no unacceptable risks associated

with the unit

Furnace Unit Group RBC ReportRev APP B pc2 B 1 Rev May 2004

2 0 DISCUSSION

2 1 UNIT HISTORY AND DATA REVIEW

The Furnace Group is located in the central area of the mam plant structure Each unit within the Group

uses heat as part of the industrial process and consists of heavy machinery or furnaces in buildings where

there is no routine access to environmental media Similar environmental conditions also exist at these

units because the ground surface is either paved or consists of a concrete floor covered in wood floor

block

The Group is comprised of FSA Units IPO 04 (50 Inch Continuous Heat Treatment Line {Former Paint

Line location}) IPO 05 (Ingot Plant Melting Furnaces and Casting Pits) IPO 08 (Soaking Pits), and IPH

09 (No 8 and No 9 Vertical Heat Treatment Furnaces)

Samples collected from three investigations conducted in September 1991 October 1997 and

November 1998 were used in this risk assessment Samples are listed in Table 2-2 and illustrated in

Figure 2-2 The analytical results of these sampling investigations represent an adequate data set to

evaluate potential risks from site associated media for this RBC Report No soil data exists for the unit,

IPH 09 however this does not represent a data gap because the unit is entirely within a building and

ground surface is concrete and process knowledge indicates significant concentrations of site COIs are

unlikely A description of each of the sampling investigations follows

In September 1991 Geraghty and Miller conducted an investigation in conjunction with excavation work

performed by Castle Construction for the VFX Furnace area within IPO 04 and IPO 08 In the first

phase samples were collected in the area of IPO-04 to determine if PCBs and VOCs were present in soil

beneath the furnace foundation The data was used to determine the proper disposal of the excavated

soils in accordance with state and federal regulations The subsurface investigation included the

collection of three soil samples from locations beneath the proposed excavation area Two of the samples

were submitted for analysis of PCBs and VOCs In the second phase three surficial composite soil

samples were collected in the area of IPO 04 from several locations beneath the floor The samples were

submitted for analysis of PCBs and VOCs Approximately 1 200 cubic yards of soil were excavated for

the construction project and stockpiled in a containment cell on site

In September 1997 soil samples were collected from the area of the Soaking Pits (IPO 08) during

decommissioning of the northern furnace The objective of the sampling was to determine if site

Furnace Unit Group RBC ReportRev APP B pc2 B 2 Rev May 2004

constituents were present in soil beneath the unit After the floor was removed a hand auger was used to

collect six samples The samples were analyzed for VOCs PCBs and SVOCs

In November 1998 soils samples were collected at the Ingot Plant Melting Furnaces and Casting Pits

(IPO 05) Samples were collected using a hand auger from an area where the floor had been removed for

a repair project The samples were analyzed for VOCs SVOCs PCBs TPH and extractable

hydrocarbons

2 2 POTENTIAL EXPOSURE PATHWAYS

The UCM (Figure 2 3) includes the excavation repair worker and the excavation construction worker as

the potential receptors for surface/subsurface soil Incidental exposure to subsurface soil may occur if

repair to utility lines is performed or if soils are excavated for construction work Surface soil surface

water and sediment are not present within the Unit Group since all of the units occur within main plant

buildings There is no routine exposure to constituents in groundwater beneath the Unit Group because

groundwater is not used or encountered during operations at this Unit Group

A repair worker may contact subsurface soils while repairing underground utilities in the area covered by

the Furnace Group The construction worker may contact subsurface soil during the construction of

building foundations installation of new equipment or facilities etc This Unit Group is located in areas

that may potentially be targeted for future development where the construction worker may become an

applicable receptor

Because the Furnace Group is not identified as a perimeter unit in the CSM, the off site resident

groundwater exposure pathway was not identified as a potentially relevant exposure scenario

There is no ecological habitat at this unit group and therefore, ecological risk is not evaluated

2 3 CONSTITUENTS OF POTENTIAL CONCERN

There were no detected COPCs in Foil Mill Unit Group II soils only some SQLs exceeded PRGs

Therefore EPCs for all COPCs are the SQL

For each exposure scenario benzo(a)pyrene and dibenz(a,h)anthracene have the same 10"* cancer RBCs

These are 10 mg/kg for the excavation repair worker 21 mg/kg for the excavation construction worker

0 87 mg/kg for the frequent on site worker 4 4 mg/kg for the occasional on site worker and 8 7 mg/kg

Furnace Unit Group RBC ReportRev APP B pc2 B 3 Rev May 2004

for the infrequent on site worker The EPC (maximum SQL) for both benzo(a)pyrene and

dibenz(a h)anthracene is 0 4 mg/kg which does not exceed any of the calculated RBCs

2 4 EXISTING ALCOA CONTROL MEASURES

Although the results of the risk evaluation determined that EPCs for COPCs were below calculated site

specific RBCs for the relevant exposure scenarios Alcoa maintains plant wide control measures that

protect against possible exposure to contaminated environmental media An overview of these control

measures is provided below

Access to the public is controlled by a security fence with manned gates that control access to the site In

addition to the fence the plant Security Department makes routine security rounds to monitor for

unauthorized personnel on site Although the fence and security procedures may not necessarily

eliminate unauthorized public access to the site they do reduce the potential for routine uncontrolled

exposure to environmental media

More applicable to this unit is the Alcoa Drilling or Digging Permit required prior to any excavation or

drilling into floors walls, ceilings, courtyards or other areas outside of buildings (Davenport Works

Contractor Safety Practices Manual January 1996) This process requires that workers utilize appropriate

personal protective equipment when digging into areas known or suspected to be contaminated A copy

of this internal Alcoa permit is included as Figure B 1 With this process a Digging or Drilling Permit

requisition form (Figure B-2) is completed that details the project This form and the drilling permit is

routed to appropriate electrical and mechanical design engineers area maintenance planners electrical

and mechanical maintenance personnel, a telephone company representative and an environmental

control representative if soil removal is required Information on the permit includes the date permit

number location building number, column number, detailed sketch start date completion date and the

requester s name The permit specifically indicates whether or not soil will be removed if it is

environmental control must approve the permit As part of the environmental approval of the permit it is

determined if excavation will be done in an area of known or suspected contamination as identified by

the Facility Site Assessment If it is and data are available those data are used to manage the heath and

safety aspects of the excavation work If data are not available but the area is suspect the project

engineer is required to collect the appropriate data before the job can proceed In this case the digging

permit is approved for soil sampling only and the final digging permit must be reviewed and approved by

environmental control after the data are received Environmental approval for excavation is only given if

the area is clean or if a plan has been prepared to address contamination issues

Furnace Unit Group RBC ReportRev APP B pc2 B 4 Rev May 2004

Another current program ensures that major projects are not considered for areas of known or suspected

soil or groundwater contamination unless a plan to address the potential problem is in place When funds

for a project are requested a Pre Project Environmental Checklist is required by the environmental

manager of the plant The purpose of the checklist is to ensure that all environmental aspects of a project

are considered in the funding The checklist has been in place for several years and now includes

questions specifically related to the 1995 AOC A copy of this checklist is attached as Figure B 3

As part of the plant-wide general safety program projects that have the potential for accident injury or

exposure to potentially unsafe conditions require the preparation of a Job Safety Analysis (JSA) before

the job can proceed The JSA forms the basis of daily job site safety review meetings to discuss

potential safety hazards associated with the particular job A JSA for working with PCB contaminated

materials was developed in 1987 and is used whenever ajob involves potential exposure to PCBs

Use of the above discussed Drilling and Digging Permit Pre Project Environmental Checklist and Job

Safety Analysis have proven effective in minimizing the potential for physical and electrical safety

hazards as well as uncontrolled exposure to contaminated media These systems will only become more

effective as RBC investigations are completed and more data are generated regarding soil and

groundwater contamination

2 5 ADDITIONAL SCENARIOS AND MANAGEMENT CONTROLS

The quantitative analysis indicated that the Furnace Group does not pose unacceptable risks to the

excavation construction and repair worker As a conservative measure Alcoa evaluated whether other

site specific scenarios may be applicable in the future should there be a change in Alcoa s land use at the

unit The objective of this evaluation was to evaluate whether a change in land use could change the

conclusions regarding potential risk to human health or the environment and assess the need for short-

term management controls to manage these risks at the Unit Group

A review of the Menu of Alcoa Specific Site Wide Exposure Scenarios in the 1995 AOC revealed that

the frequent occasional, and infrequent on site workers are potential future exposure scenarios A

comparison of EPCs for the COPCs at the Unit Group to RBCs calculated for the same receptor scenarios

at other units (e g Bone Yard) indicate that no unacceptable risk would be presented to these potential

future receptors An uncertainty that exists with this comparison is that the EPCs are based on subsurface

soil data whereas the potential future receptors could be exposed to surface soils For comparison

purposes it was assumed that the subsurface soil EPCs were representative of conditions in surface soils

Furnace Unit Group RBC ReportRev APP B pc2 B 5 Rev May 2004

3 0 CONCLUSION

There are no unacceptable risks under current (excavation repair worker and excavation construction

worker) and potential future (frequent occasional and infrequent on site workers) exposure

scenarios at the Furnace Group However unit IPH 09 (No 8 and No 9 Vertical Heat Treatment

Furnaces) will be identified in the Plant s STMP as a unit where data are lacking The lack of data at

IPH 09 underscores the importance of Alcoa's Drilling and Digging Permit Program In the event an

Alcoa land use change will expose on-site workers to soils currently under IPH 09, or work in the

area will result in exposure to excavation repair workers or construction workers soil samples will

need to be collected under the Digging Permit Program The listing of this unit in the STMP may be

withdrawn in the future if data are collected that show there are no unacceptable risks associated with

the unit In addition because the Unit Group is within the mam plant it will be covered by a long

term management plan that would protect human health and the environment associated with any

change in land use that results from a change in ownership of the property Other than the

identification of unit IPH 09 in the STMP as a unit where data are lacking Alcoa requests an

unconditional no further action for industrial use of this unit

Evaluation of groundwater at this unit is discussed in the Groundwater RI Evaluation of risks to

ecological receptors is not evaluated because there is no ecological habitat

Furnace Unit Group RBC ReportRev APP B pc2 B 6 Rev May 2004

Table B-lUnit Recommendation, Furnace GroupAlcoa Davenport Works Riverdale Iowa

MEDIA

Surface Soil(Potential Future AlcoaLand Use)

RECEPTOR

On Site WorkerFrequent

Occasional

Infrequent

RECOMMENDATIONS

No further action1

No further action1

No further action1

JUSTIFICATION

EPCs do not exceedcancer or noncancerRBCsEPCs do not exceedcancer or noncancerRBCsEPCs do not exceedcancer or noncancerRBCs

Surface/SubsurfaceSoil(Current and FuturePotential Alcoa LandUse)

Excavation Worker

Construction

Repair

No further action'

No further action1

EPCs do not exceedcancer or noncancerRBCsEPCs do not exceedcancer or noncancerRBCs

Groundwater Off Site Resident Defer to Groundwater RI No groundwater useat unit groundwateris being evaluated inthe Groundwater RI

Bold and italicized text is applicable at this Unit GroupEPC Exposure Point ConcentrationRBC Risk Based Concentration

'Unit IPH 09 will be identified in the Plant s Short Term Management Plan (STMP) as a unit where dataare lacking The listing of this unit in the STMP may be withdrawn in the future if data are collected thatshow there are no unacceptable nsks associated with the unit

Rev APP B pc2 Page 1 of 1Furnace Unit Group RBC Report

Rev May 2004

Figure B-1

DIGGING OR DRILLING PERMIT

DATE

DUX: NOCOLUMN NOS.O erWT No

SKETCH ATTACHED?

START DATE

PERMIT NO N° 5774

YES NO

EST COMPLETION DATE\TIME_

REQUESTED BY

OF DEPARTMENT

WILL SOIL REMOVAL BE REQUIRED FOR THIS PROJECT?YES *MMM>Cin*MMMdCau<lfaravpMIU>lllliltaMr

NO

CONDUITS AND OTHER HAZARDS IN THE AREA

»t rvII rv

ITCAMHATUIAL OA»

mo. OIL•VAT OIL

LIQUID ALUMCONDIHlAn

C-CUA* D-DiAD AJUJVl COIIOn

WARNING TAGS ON BREAKERS SWITCHES VALVES7

YES NO

EQUIPMENT TAGGED OUT

REMARKS

NECESSARY PRECAUTIONS HAVE BEEN TAKEN

ENVIRONMENTAL CONSIDERATIONS

SOIL SAMPLE? REQUIRED? YES NO_

SAMPLING PUN DEVELOPED? YES NO_

CLEARED FOR SOIL SAMPLING ONLY

SOIL ANALYSIS OBTAINED? YES.

SOIL DISPOSAL PLAN DEVELOPED? YES_

CLEARED FOR PROJECT EXCAVAT1ON_

NO-NO

EMERGENCY TELEPHONE NUMBERS:

SPILLS EXT 2200

SECURITY EXT .2201

FIRE OR AMBULANCE EXT 2200

UTILITY SUPERVISOR EXT 2210

WHEN ANYDICCINC OR DRILLING IS PLANNED IN THE FLOORSWALLS OR CEILINGS OF BUILDINGS IN COURTYARDS OP INOTHER AREAS OUTSIDE BUILDINGS A DIGGING OR DRILLING PERMIT MUST BE OBTAINED BEFORE OPERATIONS START

OBTAINING DIGGING OR DRILLING PERMITS

A The designated Alcoa Engineer shall obtain the Digging or Drilling Permitfor prefect* originated by engineering

B The appropriate Maintenance Planner shall obtain the Digging or DrillingPermit (or projects originated bv maintenance

C The permit requeat u initialed bv complel ng and routing a Digging orDrilling Permit Request form to identify any potential nlerferenee prob-lems or environmental concerns

D The Mill Maintenance Utility Supervisor Electrical Maintenance Sunerv•or and Telephone Company Representative will determine the local on ofany underground cables, piping, or electric I nes m the area. The perm t •»quires the signatures of thaw people to verify that the location of underground line* have been determined

E. For projects (hat require soil removal the Environmental Consideration*seebon of the Digging Pern II shall be signed following procedure A CatxA- If soil samples are required 2-4 weeks may be needed before thepermit can be cleared for protect excavation

F If the project is cleared for sol sampling only the pink copy of the Digging or Drilling Permit a lo be posted at the fob site. The green copy willbe retained by Environmental Control unl I leal results are obla ned Allhat time, the green copv will be signed and returned to the requestor forpostang during excavation.

DIGGING OR DRILLING SAFETY RULES

I The Electrical (In I Supervisor and Mill Maintenance Utility Supervisorshall lake the -ar steps to see that work can be done safely and sign theDigging Permit Whet ver predial circuits involved shall be de-encrgisadand valves shut off Normal lag-cnt procedures shall be followed where re-quired

2. Prior to any digging or drilling, the designated Alcoa Engineer orMaintenance Planner shall advise the Alcoa Supervisor or Contractor Incharge of excavation of any pole- laJ under ground Interferences.

3 For protect* thai require soil removal the designated Alcoa Engineer orMaintenance Planner shall advise the Alcoa Supervisor or Contractor mcharge of excavation of the potential for encountering contaminated mate-rial The Alcoa Supervisor or Contractor is responsible for protecting (hehealth and safely of employee* through monitoring and/or the use ofappropriate personal protecuce equipment For assistance regarding man!lonng or personal protective equipment rcqu remenl*. contact the AlcoaIndustrial Hygtcnisl

4 The Uml Supervisor or Requea or shall post the Permit m the work area andproceed with work. If the Permit » cleared only for Soil Sampling, the pinkcopy of the permit to lo be posted If no soil removal to involved and/or Ineentire project to cleared by Environmental Control, the green copy of thepermit shall be posted Digging or Drilling • not proceed unleas • propertysigned permit to posted at the fob site.

5 For projects involving excavation deeper than 4 feet compliance withOSHA Standard 1926. Subpart P •Excevauon to mandatory

6 Evidence of past contamination discovered during excavation, or the re-lease of oils or chemicals Into the soil sewer system* or outfalls caused byan accident during excavation may have lo be reported lo EnvtronaMnia)Regulatory Agencies wllhm 4 hour* of Ine occurrence. If excavation rsiarsa release or uncovers evidence of peat comuunmalion. report II Immediatelyto ExL 2200 to Inltate the proper reporting procedure.

Figure B-2

DIGGING OR DRILLING PERMIT REQUISITION

•uchea perma.)

PROJECT TTTLE

REQUEST DATE REQUIRED DA

IS SOU. REMOVAL REQUIRED? ACCOU11£S & AiUbona

ntxrud EQUV/BLDO

,TE- REQUESTED BY

MTNO 0Uq far «a mnovmJ R02924

i

ROUTING

Elec Deugn A C Boboth J L Dus rj

Mech Dcufn J J Radio"

Arc* Muni PUnner

Ttlepbonc Con^any Rep Larrv Avcrcamp

EovuoaatBUl Control M k Sonkien

RequeaorReq d Onlv For So 1 Remo al

EXCAVATION DESCKIPnON (INCIJODE LOCATION - SEE BACK)

_

REFERENCE DRAWINGS (POTENTIAL INTERFERENCES)EMBEDDED CONDUIT

PROCESS PIPING

UnLTTY PIPING

EQUIPMENT GENERAL ARRANGEMENT

THIS SECTION TO BE COMPLETED BY ALCOA ENVIRONMENTAL CONTROL

Ha c umplei been collected in thu tna bcfon'

If yei are they adequau for • daemon on this axcavauon?

If appropriate provide tkeich on tevcin aide and aotc ban «...

Approval 10 proceed with Ufflpt* eoUecuoa fiven by

(Aoaefa copy of analytical reailu)

(sipuoiic)

Rot Engr Manual IV P 1 IV P 6

Figure B-3 1 OF 4

DAVENPORT WORKS PROJECT APPROVAL REQUESTFOR <S250 000 PROJECTS

APPROVAL ROUTING INITIAL DATE

BUDGET SEC

CBXEF/SDPV

MECH CHIEF/SUPV

IB. SPECIALIST

SUPERINTENDENT

MANAGER.

WORKS MANAGER.

LD PALMER

J P CLARK

PROPERTV ACCT R.V MCQUEEN

SHOP ORDER NO

ACCOUNT NUMBER.

FORECAST NUMBER.

BCPENDITURE TOTAL (000 «)

DATE.

AUTH NUMBER

DATE.

CAPITAL.1222

REASON FOR EXPENDITUREREASON

FOCAL POINT

100*

PROJECT TITLE

PROJECT SCOPE. (bneC one pangnph)

PROJECT BENEFITS (Economic. ROR (if available) POP financial indicator reduced set up tune, etc)

SAFETY IMPACT (if applicable)

ENVIRONMENTAL IMPACT An environmental pie-project checklist has been completed and a)Q there are noenvironmental impact issues, or b)Q all envuonmemal impact issues have been resolved with the emronmeatal department^rmmt fgj jg thic rCQUCJt, »"^ U CU0U&1TV TCHllt '" tbC IbllOWinf fTlff***

PREPARED BY NAME

PROJENGR.

MFG/IND ENGR.

OTHER.

SIGNATURE PATE

INFO COPIES G O PRATTJP CLARKJN WOOD

LD PALMERJ C FUNKC M.OSBORNE

J V VELEZXWHTTTY

C ABTJELR.J MEYBl

2 OF 4

PRE-PROJECT>XNVIRONMENTALCHECigLIST

Instructions Please complete this checklist pner to all reouestsfor project funds. If you answered yes or don t know toany of Hie ovations, please contact the luted individual In the environmental department for assistance When all issuesnave been resolved, complete the environmental section of the PAR and attach the completed checklist to the copy of thePAR that goes to the environmental manager

Project Title.

Budget Forecast No

AIR

Win there be uyexhnitt to the oaudethnafh a new acker vent? G Q

wm there be any chances to the exhaust characteristics through an existing stack or vent(ix. Q Oflow rate. temperature. Back configuration (size, discharge direction, or heightD?

Win there be a change in the chemical nakeop or quantity of ur stream exhumed? (When OD•niwenng this consider the effect of temperature en evaporation, chemical racoons, and the•ttifaitit gf e

ftmage of equipment or excavation natenal)?

wni then be any chance i& tf"*^ Ttntr>^irr of Aluminum pass*lbs. tbrouah a Mfcf of

If the answer to any of the above Is Yes or you den t Jmnr (?) contact Wayne Jochmam.

WATER

Will there be any change in water uage? ODD

Win there be any change m chemicals that have the potential to reach any plant wade water Q Q Qneam (norm sewer industrial wane sewer auttary aewer)?

Will any plant wanewater drain be reloated? O O O

Will th> ffrmpryi^mffl/Itunllntiftfi nf itin nmMfl |fit»iimt {hf flpPtltlffB <*f *"V *^ "^'ftfl? [""1 J~~\ J~~\

If the answer to any of the above is Ye* or you dan tbwwf) contact Anita Berry

SPILL PREVENTION

Win there be any chanfein the number of ctorage tanks, vauru.orcontaiaen? ODD

Wai any material (except dean water), be transferred via piping or other means. (Le* ditch or O Q Oaewer)?

If the answer to any of the above is Yes or you don t know (*) contact Antta Berry

3 OF 4

SOLID WASTEWiDthoebeai^buildiaciieniolttonarthefteiovilafai^ebcoleteeqmpnieat^tptB^ O Q Q

Will there be* need to hiadte or dispose of isbesMs? D D D

Wfflthupn5caia^m»chingeintbeiattine|cntntwn(rf«lidwi«efcqmni<aff-«ae D D Ddupocv?

Will the project duturb>5 acres of pond? ODD

Does thu project require wry exavuiou? D D D

tfthtantwer to any of Iht above is Yes or you don't lotow (t) contact Linda Hoehn.

CHEMICALS

Is there a change in quantity or type of chenual media the process? D D D

Will th» pmr^ y/MjmpmMrt gfnfrU* any ^hymiral «i««t*rt [ | [ | [ |

If the answer to the above uY*s or ym don tlmo* contact Sttve Ro&n*

GENERAL

If this prefect requires adisgincpennit. it ismuarea cowered by the Remedituon Consent Q n f~1Order Jf yes or you don t know (7) contact Marshall SonJatn or Bud S&rttsr,

t f y u , c o m p 1 e u Note ContnlSh^ O D Dcontact Dan Bedell

Will this pngeci involve any ndio^aiwtoatctT If yes. contact SusmLnthautr- D CD D

Wni lhi« jmjftj tnvntvp «ny migr tbMjpti^ or HMT ar antf«H firrf^ nlrriw t̂ fhmgTt? ^fp D D D

contact Linda JJoehn.

Is there iny used equipment from a noa-Dtvenpon source bang used in this piojecr? ̂ >w D D Dcontact Linda Hoehn

Is there uybtjhun|bein(itplaoed or added? ^T» contact Jim Wood. Q O Q

4 OF 4

PROJECT APPROVAL REQUESTEnvironmental Pre-Project Checklist Procedures

Requester preparescstnnates and stoiYfor the project and

lal checklist

Resolve wilt ipjiiupiutcamraaneotal departmentpence pnor to mating

for Appro val

tflftion of flic PARoobngCOlUuflOS tOf ulC flOCIuOOS

miked yes, then route projectrocjuest rorippiovu

Attach completed checklist to thecopy thtt goes to eBvin

File<S250KApprove and fik>S250K

Requester pulls op PAR andchecklist from SARDS fbnnfie

al Department

Eovmnmeotil]

£nvmomeotil Deputmeot