Prepared for
Carus Corporation and
Carus Chemical Company
1500 Eighth Street
P.O. Box 1500
LaSalle, Illinois 61301-3500
U.S. Environmental Protection
Agency Region 5
77 West Jackson Boulevard
Chicago, Illinois 60604
FINAL
REMEDIAL INVESTIGATION REPORT
MATTHIESSEN AND HEGELER ZINC COMPANY SITE
LASALLE, ILLINOIS
Volume 1 of 6
Prepared by
Geosyntec Consultants
134 North LaSalle Street
Suite 300
Chicago, Illinois 60602
SulTRAC
1 South Wacker Drive
37th Floor
Chicago, Illinois 60606
Geosyntec Project Number CWR1710
JUNE 2012
FINAL
REMEDIAL INVESTIGATION REPORT
REVISION 0
FOR
MATTHIESSEN AND HEGELER ZINC COMPANY SITE
LA SALLE COUNTY, ILLINOIS
Prepared for
United States Environmental Protection Agency
Region 5
77 West Jackson Boulevard
Chicago, Illinois 60604
Work Assignment No. : 132-RICO-B568
EPA Region : 5
Date Prepared : June 1, 2012
, Contract No. : EP-S5-06-02
Prepared by : SulTRAC
SulTRAC Project Manager : Jennifer Knoepfle
Telephone No. : (312) 443-0550 ext. 21
EPA Work Assignment Manager : Demaree Collier
Telephone No. (312) 886-0214
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TABLE OF CONTENTS
VOLUME 1 Report Text
SULTRAC DISC 1 OF 2 Appendices S-1 through S-9
SULTRAC DISC 2 OF 2 Appendices S-10 through S-46
GEOSYNTEC DISC 1 OF 2 Appendices G-2-1 through G-5-2
GEOSYNTEC DISC 2 OF 2 Appendix RA – Final Risk Assessment
VOLUME 2 Sections 1, 2, 3, 5, and 6 Figures
VOLUME 3 Section 4 Figures
VOLUME 4 Sections 2, 3, 5, 6, and 9 Tables
VOLUME 5 Section 4 Tables (Tables 4.0-1 through 4.2.2-2)
VOLUME 6 Section 4 Tables (Tables 4.2.2-3 through 4.3.3-4)
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VOLUME 1
EXECUTIVE SUMMARY .................................................................................................................. ES-1
1.0 INTRODUCTION....................................................................................................................... 1-1
1.1 PURPOSE OF REPORT ..................................................................................................... 1-2
1.1.1 Roles of Parties Involved ....................................................................................... 1-2
1.1.2 Integration of OU1 and OU2 Investigations .......................................................... 1-3
1.2 SITE BACKGROUND ....................................................................................................... 1-3
1.2.1 Site Description ...................................................................................................... 1-3
1.2.1.1 OU1 Description .................................................................................... 1-4
1.2.1.2 OU2 Description .................................................................................... 1-5
1.2.2 Site History ............................................................................................................ 1-5
1.2.2.1 OU1 History ........................................................................................... 1-6
1.2.2.2 OU2 History ........................................................................................... 1-7
1.2.3 Previous Investigations .......................................................................................... 1-8
1.2.3.1 OU1 Investigations ................................................................................ 1-9
1.2.3.2 OU2 Investigations .............................................................................. 1-12
1.3 REPORT ORGANIZATION ............................................................................................ 1-15
2.0 RI ACTIVITIES ......................................................................................................................... 2-1
2.1 OU1 INVESTIGATION ACTIVITIES .............................................................................. 2-1
2.1.1 Soil Investigation ................................................................................................... 2-2
2.1.1.1 Phase I Soil Investigation ...................................................................... 2-3
2.1.1.2 Phase II Soil Investigation ..................................................................... 2-5
2.1.2 Groundwater Investigation ..................................................................................... 2-5
2.1.2.1 Phase I Groundwater Investigation ........................................................ 2-6
2.1.2.2 Phase II Groundwater Investigation ...................................................... 2-8
2.1.3 Surface Water and Sediment Investigation ............................................................ 2-9
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2.1.3.1 Phase I Surface Water and Sediment Investigation ............................... 2-9
2.1.3.2 Phase II Surface Water and Sediment Investigation ............................ 2-11
2.1.4 Ecological Receptor Investigation ....................................................................... 2-13
2.1.4.1 Phase I Ecological Characterization .................................................... 2-14
2.1.4.2 Phase II Ecological Characterization ................................................... 2-19
2.1.4.3 Additional Ecological Characterization ............................................... 2-21
2.1.5 Air Sampling Investigation .................................................................................. 2-22
2.2 OU2 INVESTIGATION ACTIVITIES ............................................................................ 2-22
2.2.1 Soil Investigation ................................................................................................. 2-23
2.2.1.1 Phase I Soil Investigation .................................................................... 2-23
2.2.1.2 Phase II Soil Investigation ................................................................... 2-26
2.2.2 Groundwater Investigation ................................................................................... 2-28
2.2.2.1 Phase I Groundwater Investigation ...................................................... 2-29
2.2.2.2 Phase II Groundwater Investigation .................................................... 2-32
2.2.3 Building Material Investigation ........................................................................... 2-35
2.2.3.1 Phase I Building Material Investigation .............................................. 2-35
2.2.3.2 Phase II Building Material Investigation ............................................. 2-36
2.2.4 Pile Investigation .................................................................................................. 2-37
2.2.5 Surface Water Investigation ................................................................................. 2-37
2.2.5.1 Phase I Surface Water Investigation .................................................... 2-37
2.2.5.2 Phase II Surface Water Investigation ................................................... 2-38
2.2.6 Residential Area/Off-Site Area Investigation ...................................................... 2-41
2.2.6.1 Phase I Residential Area/Off-Site Area Investigation ......................... 2-41
2.2.6.2 Phase II Residential Area/Off-Site Area Investigation ........................ 2-42
2.2.7 Ecological Receptor Investigation ....................................................................... 2-45
2.2.7.1 Phase I Ecological Receptor Investigation .......................................... 2-45
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2.2.7.2 Phase II Ecological Receptor Investigation ......................................... 2-49
2.2.8 Air Sampling Investigation .................................................................................. 2-50
2.3 SITE-WIDE BACKGROUND SOIL INVESTIGATIONS.............................................. 2-54
3.0 PHYSICAL CHARACTERISTICS OF THE SITE ................................................................ 3-1
3.1 GENERAL SETTING ........................................................................................................ 3-1
3.1.1 Surface Features ..................................................................................................... 3-1
3.1.2 Subsurface Manmade Features .............................................................................. 3-3
3.1.3 Surface Water Hydrology ...................................................................................... 3-5
3.1.4 Weather Conditions ................................................................................................ 3-5
3.1.5 Demography and Land Use .................................................................................... 3-7
3.1.6 Regional Geology .................................................................................................. 3-7
3.1.7 Regional Hydrogeology ......................................................................................... 3-8
3.1.8 Ecology .................................................................................................................. 3-9
3.2 OU1 FEATURES .............................................................................................................. 3-10
3.2.1 Soils ...................................................................................................................... 3-10
3.2.2 Geology ................................................................................................................ 3-11
3.2.3 Hydrogeology....................................................................................................... 3-14
3.2.3.1 Hydrogeologic Characteristics ............................................................. 3-15
3.2.3.2 Variations in Water Levels .................................................................. 3-16
3.2.3.3 Groundwater Gradients, Recharge and Discharge ............................... 3-17
3.2.3.4 Summary of Hydrogeologic Conditions .............................................. 3-19
3.3 OU2 FEATURES .............................................................................................................. 3-20
3.3.1 Soils ...................................................................................................................... 3-20
3.3.2 Geology ................................................................................................................ 3-21
3.3.2.1 Bond Formation of the McLeansboro Group of the Pennsylvanian System.................................................................................................. 3-22
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3.3.2.2 Lemont Formation ............................................................................... 3-24
3.3.2.3 Equality Formation .............................................................................. 3-24
3.3.2.4 Artificial Fill ........................................................................................ 3-24
3.3.3 Hydrogeology....................................................................................................... 3-25
3.3.3.1 Hydraulic Conductivity........................................................................ 3-26
3.3.3.2 Groundwater Flow ............................................................................... 3-27
3.4 SITE-WIDE INTERPRETATION .................................................................................... 3-29
3.4.1 Soils ...................................................................................................................... 3-29
3.4.2 Geology ................................................................................................................ 3-29
3.4.2.1 Artificial Fill ........................................................................................ 3-30
3.4.2.2 Cahokia Formation and Holocene Alluvium ....................................... 3-32
3.4.2.3 Equality Formation .............................................................................. 3-32
3.4.2.4 Lemont Formation ............................................................................... 3-32
3.4.2.5 McLeansboro Group ............................................................................ 3-33
3.4.3 Site-Wide Hydrogeology ..................................................................................... 3-35
3.4.3.1 Hydraulic Conductivity........................................................................ 3-35
3.4.3.2 Groundwater Gradients ........................................................................ 3-36
3.4.3.3 Recharge and Discharge ...................................................................... 3-37
3.4.3.4 Water Level Variation ......................................................................... 3-37
3.4.3.5 Summary .............................................................................................. 3-38
4.0 NATURE AND EXTENT OF CONTAMINATION ............................................................... 4-1
4.1 OU1 INVESTIGATION AREAS AND ANALYTICAL RESULTS ................................ 4-3
4.1.1 OU1 Investigation Areas ........................................................................................ 4-4
4.1.1.1 Plant Area .............................................................................................. 4-4
4.1.1.2 Slag Pile ................................................................................................. 4-5
4.1.1.3 Little Vermilion River ........................................................................... 4-5
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4.1.2 OU1 Soil Results .................................................................................................... 4-6
4.1.2.1 Plant Area Soil Results .......................................................................... 4-6
4.1.2.2 Slag Pile Area Soil Results .................................................................. 4-12
4.1.3 OU1 Groundwater Results ................................................................................... 4-19
4.1.3.1 Plant Area Groundwater Results .......................................................... 4-21
4.1.3.2 Slag Pile Groundwater Results ............................................................ 4-25
4.1.4 OU1 Sediment and Surface Water Results .......................................................... 4-29
4.1.4.1 Slag Pile Sediment Results .................................................................. 4-29
4.1.4.2 LVR Sediment and Surface Water Results .......................................... 4-35
4.1.5 Vertical Extent of Contamination in Soil and Groundwater at OU1 ................... 4-44
4.1.5.1 Vertical Extent of Metal Contamination in Soil and Groundwater ..... 4-45
4.1.5.2 Vertical Extent of VOC Contamination in Soil and Groundwater ...... 4-49
4.1.5.3 Vertical Extent of SVOC Contamination in Soil and Groundwater .... 4-50
4.1.5.4 Vertical Extent of PCB Contamination in Soil and Groundwater ....... 4-51
4.1.5.5 Vertical Extent of Pesticides Contamination in Soil and Groundwater ........................................................................................ 4-51
4.1.6 Horizontal Extent of Contamination in OU1 ....................................................... 4-51
4.1.6.1 Horizontal Extent of Contamination in Soils ....................................... 4-51
4.1.6.2 Horizontal Extent of Contamination in Groundwater .......................... 4-56
4.1.6.3 Horizontal Extent of Contamination in Sediment and Surface Water.................................................................................................... 4-62
4.1.7 OU1 Air Results ................................................................................................... 4-72
4.2 OU2 RESULTS ................................................................................................................. 4-73
4.2.1 OU2 Investigation Areas ...................................................................................... 4-74
4.2.1.1 Investigation Area 1: Building 100 ...................................................... 4-75
4.2.1.2 Investigation Area 2: Rolling Mill ....................................................... 4-75
4.2.1.3 Investigation Area 3: Former Main Industrial Area ............................ 4-76
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4.2.1.4 Investigation Area 4: North Area/Northeast Periphery Area ............... 4-76
4.2.1.5 Investigation Area 5: Residential Area/Off-site Area .......................... 4-76
4.2.1.6 Groundwater Investigation Areas: WBZ1 and WBZ2 ......................... 4-77
4.2.2 OU2 Soil Results .................................................................................................. 4-77
4.2.2.1 Investigation Area 1: Building 100 ...................................................... 4-82
4.2.2.2 Investigation Area 2: Rolling Mill ....................................................... 4-97
4.2.2.3 Investigation Area 3: Former Main Industrial Area .......................... 4-113
4.2.2.4 Investigation Area 4: North Area/Northeast Periphery Area ............. 4-134
4.2.2.5 Investigation Area 5: Residential Area/Off-site Area ........................ 4-145
4.2.3 OU2 Building Material Results .......................................................................... 4-150
4.2.3.1 Investigation Area 1: Building 100 .................................................... 4-151
4.2.3.2 Investigation Area 2: Rolling Mill ..................................................... 4-154
4.2.3.3 Investigation Area 3: Former Main Industrial Area .......................... 4-158
4.2.4 OU2 Pile Results ................................................................................................ 4-167
4.2.4.1 Investigation Area 1: Building 100 .................................................... 4-167
4.2.4.2 Investigation Area 2: Rolling Mill ..................................................... 4-174
4.2.4.3 Investigation Area 3: Former Main Industrial Area .......................... 4-180
4.2.5 OU2 Groundwater Results ................................................................................. 4-188
4.2.5.1 OU2 WBZ1 Monitoring Well Results ............................................... 4-190
4.2.5.2 OU2 WBZ2 Monitoring Well Results ............................................... 4-217
4.2.6 OU2 Surface Water Results ............................................................................... 4-236
4.2.6.1 Metals and Cyanide ........................................................................... 4-238
4.2.6.2 VOCs ................................................................................................. 4-248
4.2.6.3 SVOCs ............................................................................................... 4-248
4.2.6.4 PCBs .................................................................................................. 4-248
4.2.6.5 Pesticides ........................................................................................... 4-249
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4.2.6.6 OU2 Surface Water Summary ........................................................... 4-251
4.2.7 OU2 Air Results ................................................................................................. 4-251
4.2.7.1 Investigation Area 1: Building 100 .................................................... 4-254
4.2.7.2 Investigation Area 2: Rolling Mill ..................................................... 4-254
4.2.7.3 Investigation Area 3: Former Main Industrial Area .......................... 4-254
4.3 SITE-WIDE INTERPRETATION OF RI RESULTS .................................................... 4-255
4.3.1 OU1 .................................................................................................................... 4-255
4.3.1.1 OU1 Soil Results ............................................................................... 4-256
4.3.1.2 OU1 Groundwater Results ................................................................. 4-256
4.3.1.3 OU1 Surface Water and Sediment Results ........................................ 4-257
4.3.2 OU2 .................................................................................................................... 4-258
4.3.2.1 OU2 Soil/Solid Results ...................................................................... 4-258
4.3.2.2 OU2 Groundwater Results ................................................................. 4-259
4.3.2.3 OU2 Surface Water Results ............................................................... 4-260
4.3.2.4 OU2 Air Results ................................................................................ 4-260
4.3.3 Border Areas ...................................................................................................... 4-261
4.3.3.1 Border Areas Soil Summary .............................................................. 4-261
4.3.3.2 Border Areas Groundwater Summary ............................................... 4-264
5.0 CONTAMINANT FATE AND TRANSPORT ......................................................................... 5-1
5.1 PHYSIOCHEMICAL FACTORS AFFECTING CHEMICAL FATE AND TRANSPORT ..................................................................................................................... 5-1
5.1.1 Water Solubility ..................................................................................................... 5-2
5.1.2 Adsorption/Partitioning .......................................................................................... 5-2
5.1.2.1 Inorganic Partitioning ............................................................................ 5-3
5.1.2.2 Organic Partitioning ............................................................................... 5-3
5.1.3 Vapor Pressure and Henry’s Law Constant ........................................................... 5-4
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5.1.4 Soil Chemistry........................................................................................................ 5-4
5.1.5 Physical Transport Factors ..................................................................................... 5-5
5.2 CHEMICAL PERSISTENCE ............................................................................................. 5-6
5.2.1 Volatilization .......................................................................................................... 5-6
5.2.2 Degradation ............................................................................................................ 5-6
5.3 EXPECTED CHEMICAL FATE AND TRANSPORT ...................................................... 5-7
5.3.1 Inorganic Constituents ........................................................................................... 5-7
5.3.1.1 Aluminum .............................................................................................. 5-8
5.3.1.2 Antimony ............................................................................................... 5-9
5.3.1.3 Arsenic ................................................................................................... 5-9
5.3.1.4 Barium ................................................................................................. 5-10
5.3.1.5 Beryllium ............................................................................................. 5-11
5.3.1.6 Cadmium.............................................................................................. 5-12
5.3.1.7 Chromium ............................................................................................ 5-12
5.3.1.8 Cobalt ................................................................................................... 5-13
5.3.1.9 Copper.................................................................................................. 5-13
5.3.1.10 Cyanide ................................................................................................ 5-14
5.3.1.11 Iron ....................................................................................................... 5-15
5.3.1.12 Lead ..................................................................................................... 5-16
5.3.1.13 Manganese ........................................................................................... 5-17
5.3.1.14 Mercury................................................................................................ 5-17
5.3.1.15 Nickel ................................................................................................... 5-18
5.3.1.16 Selenium .............................................................................................. 5-18
5.3.1.17 Silver .................................................................................................... 5-20
5.3.1.18 Thallium ............................................................................................... 5-20
5.3.1.19 Vanadium ............................................................................................. 5-21
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5.3.1.20 Zinc ...................................................................................................... 5-22
5.3.2 VOCs .................................................................................................................... 5-22
5.3.3 SVOCs ................................................................................................................. 5-27
5.3.4 PCBs .................................................................................................................... 5-31
5.3.5 Pesticides .............................................................................................................. 5-32
5.3.6 Asbestos ............................................................................................................... 5-35
5.4 POTENTIAL CONTAMINANT MIGRATION ROUTES FOR OU1 ............................ 5-36
5.4.1 Potential Migration of Inorganic Contaminants in Soil ....................................... 5-36
5.4.1.1 SEP Results .......................................................................................... 5-37
5.4.1.2 SPLP Results ....................................................................................... 5-45
5.4.1.3 Specialized Leachability Testing – Terrestrial and Submerged Slag Materials .............................................................................................. 5-48
5.4.1.4 TCLP Results ....................................................................................... 5-49
5.4.2 Potential Migration of Contaminants in Groundwater ......................................... 5-49
5.4.3 Potential Migration of Contaminants in Air ......................................................... 5-50
5.4.4 Potential Migration of Contaminants in Surface Water and Surface Water Runoff .................................................................................................................. 5-51
5.4.5 Potential Migration of Contaminants in Sediments ............................................. 5-52
5.5 POTENTIAL CONTAMINANT MIGRATION ROUTES FOR OU2 ............................ 5-53
5.5.1 Potential Migration of Contaminants in Soils/Solids ........................................... 5-53
5.5.1.1 Metals .................................................................................................. 5-54
5.5.1.2 VOCs ................................................................................................... 5-59
5.5.1.3 SVOCs, PCBs, and Pesticides ............................................................. 5-60
5.5.2 Potential Migration of Contaminants in Groundwater ......................................... 5-61
5.5.2.1 Metals .................................................................................................. 5-62
5.5.2.2 VOCs ................................................................................................... 5-63
5.5.2.3 SVOCs, Pesticides, and PCBs ............................................................. 5-64
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5.5.3 Potential Migration of Contaminants in Air ......................................................... 5-66
5.5.4 Potential Migration of Contaminants in Surface Water and Surface Water Runoff .................................................................................................................. 5-67
6.0 CONCEPTUAL SITE MODEL ................................................................................................ 6-1
6.1 OU1 CONCEPTUAL SITE MODEL ................................................................................. 6-1
6.1.1 Physical Characteristics ......................................................................................... 6-1
6.1.1.1 Surface Features ..................................................................................... 6-1
6.1.1.2 Geology.................................................................................................. 6-2
6.1.1.3 Hydrogeology ........................................................................................ 6-3
6.1.2 Nature and Extent of Contamination ...................................................................... 6-6
6.1.2.1 Soil Results ............................................................................................ 6-7
6.1.2.2 Groundwater Results ............................................................................. 6-8
6.1.2.3 Surface Water and Sediment Results ..................................................... 6-9
6.1.3 Contaminant Fate and Transport .......................................................................... 6-10
6.1.3.1 Potential Migration of Contaminants in Soil ....................................... 6-11
6.1.3.2 Potential Migration of Contaminants in Groundwater ......................... 6-11
6.1.3.3 Potential Migration of Contaminants in Air ........................................ 6-11
6.1.3.4 Potential Migration of Contaminants in Surface Water and Surface Water Runoff .................................................................................................. 6-12
6.1.3.5 Potential Migration of Contaminants in Sediments ............................. 6-12
6.2 OU2 CONCEPTUAL SITE MODEL ............................................................................... 6-13
6.2.1 Physical Characteristics of OU2 .......................................................................... 6-13
6.2.1.1 Surface Features ................................................................................... 6-13
6.2.1.2 Geology................................................................................................ 6-15
6.2.1.3 Hydrogeology ...................................................................................... 6-17
6.2.2 Nature and Extent of Contamination at OU2 ....................................................... 6-18
6.2.2.1 OU2 Soil/Solid Results ........................................................................ 6-19
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6.2.2.2 OU2 Groundwater Results ................................................................... 6-21
6.2.2.3 OU2 Surface Water Results ................................................................. 6-22
6.2.2.4 OU2 Air Results .................................................................................. 6-22
6.2.3 Contaminant Fate and Transport at OU2 ............................................................. 6-23
6.2.3.1 Potential Migration of Contaminants in Soils/Solids ........................... 6-23
6.2.3.2 Potential Migration of Contaminants in Groundwater ......................... 6-23
6.2.3.3 Potential Migration of Contaminants in Air ........................................ 6-24
6.2.3.4 Potential Migration of Contaminants in Surface Water and Surface Water Runoff .................................................................................................. 6-24
6.3 SITE-WIDE CONCEPTUAL SITE MODEL ................................................................... 6-25
6.3.1 Physical Characteristics ....................................................................................... 6-25
6.3.2 Geology ................................................................................................................ 6-27
6.3.3 Hydrogeology....................................................................................................... 6-28
6.3.4 Surface Water ....................................................................................................... 6-29
6.3.5 Nature and Extent of Contamination .................................................................... 6-29
6.3.5.1 Soil/Solid Matrix ................................................................................. 6-29
6.3.5.2 Groundwater ........................................................................................ 6-30
6.3.5.3 Surface Water and Sediments .............................................................. 6-30
6.3.5.4 Building Materials and Debris ............................................................. 6-31
6.3.6 Contaminant Fate and Transport .......................................................................... 6-31
6.3.6.1 Potential Migration of COIs in Soil ..................................................... 6-31
6.3.6.2 Potential Migration in Groundwater .................................................... 6-31
6.3.6.3 Potential Migration in Air .................................................................... 6-32
6.3.6.4 Potential Migration in Surface Water and Runoff ............................... 6-32
6.3.6.5 Potential Migration in Sediments ........................................................ 6-33
7.0 HUMAN HEALTH RISK ASSESSMENT ............................................................................... 7-1
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7.1 OU1 HUMAN HEALTH RISK ASSESSMENT ............................................................... 7-1
7.1.1 Data Evaluation and Selection of COPCs .............................................................. 7-3
7.1.2 Exposure Assessment ............................................................................................. 7-3
7.1.3 Toxicity Assessment .............................................................................................. 7-6
7.1.4 Risk Characterization ............................................................................................. 7-8
7.1.4.1 Summary of Risks and Hazards at the Carus Plant Area ....................... 7-9
7.1.4.2 Summary of Risks and Hazards at the Slag Pile Area ......................... 7-11
7.1.4.3 Summary of Risks and Hazards at the LVR ........................................ 7-12
7.1.4.4 Localized Impact Evaluation ............................................................... 7-13
7.1.5 Uncertainties ........................................................................................................ 7-13
7.1.6 OU1 HHRA Summary and Conclusions .............................................................. 7-14
7.1.6.1 Groundwater ........................................................................................ 7-14
7.1.6.2 Carus Plant Area .................................................................................. 7-15
7.1.6.3 Slag Pile Area ...................................................................................... 7-16
7.1.6.4 LVR ..................................................................................................... 7-17
7.1.7 Overall OU1 HHRA Conclusions ........................................................................ 7-17
7.2 OU2 HUMAN HEALTH RISK ASSESSMENT ............................................................. 7-18
7.2.1 Objectives............................................................................................................. 7-18
7.2.2 OU2 Exposure Areas ........................................................................................... 7-18
7.2.3 HHRA Approach .................................................................................................. 7-20
7.2.4 HHRA Results...................................................................................................... 7-26
7.2.4.1 Summary of Risks and Hazards at the Main Plant Area (EA1) ........... 7-26
7.2.4.2 Summary of Risks and Hazards at the Main Plant Area (EA2) ........... 7-26
7.2.4.3 Summary of Risks and Hazards at the Main Plant Area (EA3) ........... 7-27
7.2.4.4 Summary of Risks and Hazards at the Building 100 Hotspot (EA4) ... 7-27
7.2.4.5 Summary of Risks and Hazards at the Rolling Mill Area (EA5)......... 7-28
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7.2.4.6 Summary of Risks and Hazards at the Off-Site Residential Area (EA6) ................................................................................................... 7-29
7.2.4.7 Summary of Risks and Hazards at the Off-Site Mixed-Use Area (EA7) ................................................................................................... 7-30
7.2.4.8 Hot-Spot Analysis ................................................................................ 7-30
7.2.5 Uncertainties ........................................................................................................ 7-32
7.2.6 Overall HHRA Conclusions for OU2 .................................................................. 7-33
7.3 SITE-WIDE HUMAN HEALTH RISK ASSESSMENT ................................................. 7-33
8.0 ECOLOGICAL RISK ASSESSMENT ..................................................................................... 8-1
8.1 OU1 ECOLOGICAL RISK ASSESSMENT ...................................................................... 8-1
8.1.1 OU1 Screening Level Ecological Risk Assessment (Steps 1 and 2) ...................... 8-2
8.1.2 OU1 LVR Baseline Ecological Risk Assessment (Steps 3 through 7) .................. 8-4
8.1.2.1 Baseline Problem Formulation (Step 3) ................................................. 8-5
8.1.2.2 Measurement Endpoints and Study Design (Step 4) ............................. 8-8
8.1.2.3 Verification of Field Sampling Design (Step 5) .................................. 8-11
8.1.2.4 Site Investigation and Data Analysis (Step 6) ..................................... 8-11
8.1.2.5 Risk Characterization (Step 7) and Weight-of Evidence ..................... 8-13
8.1.2.6 BERA Summary and Conclusions ....................................................... 8-21
8.2 OU2 ECOLOGICAL RISK ASSESSMENT .................................................................... 8-24
8.2.1 OU2 Screening Level Risk Assessment ............................................................... 8-24
8.2.1.1 Main Plant Area – Highly Disturbed Habitat ...................................... 8-25
8.2.1.2 Next to the Main Plant Area – Disturbed with Vegetation Habitat ..... 8-26
8.2.1.3 Savannah Habitat ................................................................................. 8-26
8.2.1.4 Oak-Hickory Woodland Habitat .......................................................... 8-27
8.2.1.5 Area East of the Little Vermilion River ............................................... 8-27
8.2.1.6 Conclusions and Recommendations .................................................... 8-28
8.2.2 OU2 Baseline Risk Assessment ........................................................................... 8-28
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8.2.2.1 Next to the Main Plant Area – Disturbed with Vegetation .................. 8-32
8.2.2.2 Savannah .............................................................................................. 8-32
8.2.2.3 Oak-Hickory Woodland ....................................................................... 8-33
9.0 SUMMARY AND CONCLUSIONS ......................................................................................... 9-1
9.1 OU1 SUMMARY ............................................................................................................... 9-1
9.1.1 Nature and Extent of Contamination ...................................................................... 9-1
9.1.2 Contaminant Fate and Transport ............................................................................ 9-2
9.2 OU2 SUMMARY ............................................................................................................... 9-4
9.2.1 Nature and Extent of Contamination ...................................................................... 9-4
9.2.2 Contaminant Fate and Transport ............................................................................ 9-5
9.3 HUMAN HEALTH RISK ASSESSMENT SUMMARY .................................................. 9-6
9.3.1 OU1 Summary ....................................................................................................... 9-6
9.3.1.1 Groundwater .......................................................................................... 9-7
9.3.1.2 Plant Area .............................................................................................. 9-7
9.3.1.3 Slag Pile Area ........................................................................................ 9-9
9.3.1.4 Little Vermilion River ......................................................................... 9-10
9.3.1.5 Overall OU1 HHRA Conclusions ........................................................ 9-10
9.3.2 OU2 Summary ..................................................................................................... 9-10
9.3.3 Site Summary ....................................................................................................... 9-11
9.4 ECOLOGICAL RISK ASSESSMENT SUMMARY ....................................................... 9-12
9.4.1 OU1 Summary ..................................................................................................... 9-13
9.4.2 OU2 Summary ..................................................................................................... 9-16
9.5 CONCLUSIONS ............................................................................................................... 9-18
9.5.1 Adequacy of the RI .............................................................................................. 9-18
9.5.2 Data Limitations and Uncertainties ...................................................................... 9-18
10.0 REFERENCES .......................................................................................................................... 10-1
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LIST OF FIGURES
VOLUME 2
1.2.1-1 Site Location Map
2.1.1-1 Plant Area Sampling Locations
2.1.1-2 Slag Pile Sampling Locations
2.1.1-3 LVR Slag Sampling Locations
2.1.2-1 OU1 Monitoring Well Network
2.1.3-1 LVR Sediment Sampling Locations
2.1.3-2 LVR Surface Water Sampling Locations
2.2.1-1 Phase I Soil Boring, Pile, and Building Material Sampling Locations
2.2.1-2 Phase II Soil Boring and Building Material Sampling Locations
2.2.1-3 Phase II XRF Screening and Surface Soil Sampling Locations
2.2.2-1 Phase I and Phase II Groundwater Monitoring Well and Piezometer Locations
2.2.5-1 Phase I and Phase II Surface Water Sampling Locations
2.2.6-1 Phase I and Phase II Residential Area/Off-Site Area Sampling Locations
2.2.7-1 Ecological Sampling Locations
2.2.8-1 Asbestos Air Sampling Locations
2.3-1 Site-Wide Background Soil Sampling Locations
3.1.3-1 Site and Vicinity Map
3.1.6-1 Surface Geology of the Matthiessen and Hegeler Zinc Company Site Vicinity
3.1.7-1 Public Water Well Locations
3.2.1-1 OU1 Soils as Identified by USDA NRCS
3.2.2-1 Geologic Cross-Section A'-A"
3.2.2-2 Geologic Cross-Section B'-B" & C-C'
3.2.2-3 Geologic Cross-Section D-D'
3.2.3-1 Erosional Gully (Figure 13 from the 1994 Tech Letter Report)
3.2.3-2 September 2008 Potentiometric Surface Map Water Bearing Zone 1 (WBZ-1)
3.2.3-3 September 2008 Potentiometric Surface Map Water Bearing Zone 2 (WBZ-2)
3.2.3-4 March 2009 Potentiometric Surface Map Water Bearing Zone 1 (WBZ-1)
3.2.3-5 March 2009 Potentiometric Surface Map Water Bearing Zone 2 (WBZ-2)
3.2.3-6 Groundwater Mound, Plant Area (Figure 14 from Tech Letter Report)
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LIST OF FIGURES
3.3.1-1 OU2 Soils
3.3.2-1 Geologic Cross-Section A-A'-A"
3.3.2-2 Geologic Cross-Section B-B'-B"
3.3.2-3 MW35 Natural Gamma Log vs. Soil Boring Log
3.3.3-1 Potentiometric Surface Map for WBZ1, September 2008
3.3.3-2 Potentiometric Surface Map for WBZ2, September 2008
3.3.3-3 Potentiometric Surface Map for WBZ1, December 2008
3.3.3-4 Potentiometric Surface Map for WBZ2, December 2008
3.4.1-1 Site wide soils as identified by USDA NRCS
5.4.1-1 Sequential Extraction Procedure Data for Arsenic
5.4.1-2 Sequential Extraction Procedure Data for Cadmium
5.4.1-3 Sequential Extraction Procedure Data for Chromium
5.4.1-4 Sequential Extraction Procedure Data for Copper
5.4.1-5 Sequential Extraction Procedure Data for Lead
5.4.1-6 Sequential Extraction Procedure Data for Mercury
5.4.1-7 Sequential Extraction Procedure Data for Zinc
5.5.1-1 Surface Soil SPLP and Select Total Metals Groundwater Results
5.5.1-2 Subsurface Soil SPLP and Select Total Metals Groundwater Results
5.5.4-1 Surface Water Features and Sampling Locations
6.1.1-1 OU1 Conceptual Site Model
6.2.1-1 OU2 Conceptual Site Model
VOLUME 3
4.1.1-1 OU1 Sampling Location Map
4.1.1-2 OU1 Sampling Location Map (Detail)
4.1.2-1 Metals in Shallow Plant Area Soil
4.1.2-2 Metals in Deep Plant Area Soil
4.1.2-3 SVOCs in Shallow Plant Area Soil
4.1.2-4 PCBs in Shallow Plant Area Soil
4.1.2-5 Metals in Shallow Slag Pile Soil
4.1.2-6 Metals in Deep Slag Pile Soil
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LIST OF FIGURES
4.1.2-7 SVOCs in Shallow Slag Pile Soil
4.1.2-8 SVOCs in Deep Slag Pile Soil
4.1.3-1a Dissolved Metals in Plant Area Groundwater Historical Data: 1991-1994
4.1.3-1b Dissolved Metals in Plant Area Groundwater
4.1.3-2a Total Metals in Plant Area Groundwater Historical Data: 1991-1994
4.1.3-2b Total Metals in Plant Area Groundwater
4.1.3-3a VOCs in Plant Area Groundwater Historical Data: 1991-1994
4.1.3-3b VOCs in Plant Area Groundwater
4.1.3-4a SVOCs in Plant Area Groundwater Historical Data: 1991-1994
4.1.3-4b SVOCs in Plant Area Groundwater
4.1.3-5a Dissolved Metals in Slag Pile Groundwater Historical Data: 1991-1994
4.1.3-5b Dissolved Metals in Slag Pile Groundwater
4.1.3-6a Total Metals in Slag Pile Groundwater Historical Data: 1991-1994
4.1.3-6b Total Metals in Slag Pile Groundwater
4.1.4-1 Metals in Slag Pile Sediment
4.1.4-2 VOCs in Slag Pile Sediment
4.1.4-3 SVOCs in Slag Pile Sediment
4.1.4-4 PCBs in Slag Pile Sediment
4.1.4-5 Metals in Little Vermilion River Sediment
4.1.4-6 Dissolved Metals in Little Vermilion River Surface Water
4.1.4-7 Total Metals in Little Vermilion River Surface Water
4.1.4-8 VOCs in Little Vermilion River Sediment
4.1.4-9 SVOCs in Little Vermilion River Sediment
4.1.4-10 PCBs in Little Vermilion River Sediment
4.1.4-11 Pesticides in Little Vermilion River Sediment
4.1.5-1 Overview of Geologic Cross Sections for OU1
4.1.5-2 Total Metals in Soil - Cross Section A to A'
4.1.5-3 Total Metals in Soil - Cross Section B to B'
4.1.5-4 Total Metals in Soil - Cross Section C to C'
4.1.5-5 Total Arsenic in Soil and Groundwater - Cross Section A to A'
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LIST OF FIGURES
4.1.5-6 Total Arsenic in Soil and Groundwater - Cross Section B to B'
4.1.5-7 Total Lead in Soil and Groundwater - Cross Section A to A'
4.1.5-8 Total Lead in Soil and Groundwater - Cross Section B to B'
4.1.5-9 Total Manganese in Soil and Groundwater - Cross Section A to A'
4.1.5-10 Total Manganese in Soil and Groundwater - Cross Section B to B'
4.1.5-11 Total Zinc in Soil and Groundwater - Cross Section A to A'
4.1.5-12 Total Zinc in Soil and Groundwater - Cross Section B to B'
4.2.1-1 Current and Historic Building Index in OU2
4.2.1-2 Investigation Areas 1 through 4
4.2.1-3 Investigation Area 5
4.2.1-4 Groundwater WBZ1 and WBZ2 Areas
4.2.2-1a Soil Sampling Locations for Investigation Areas 1 through 4
4.2.2-1b Soil Sampling Locations for Investigation Area 5
4.2.2-2a Surface Soil Sample Arsenic Results
4.2.2-2b Subsurface Soil Sample Arsenic Results
4.2.2-2c Surface Soil Extent of Arsenic Impacts
4.2.2-2d Subsurface Soil Extent of Arsenic Impacts
4.2.2-3a Surface Soil Sample Cadmium Results
4.2.2-3b Subsurface Soil Sample Cadmium Results
4.2.2-3c Surface Soil Extent of Cadmium Impacts
4.2.2-4a Surface Soil Sample Lead Results
4.2.2-4b Subsurface Soil Sample Lead Results
4.2.2-4c Surface Soil Extent of Lead Impacts
4.2.2-4d Subsurface Soil Extent of Lead Impacts
4.2.2-5a Surface Soil Sample Mercury Results
4.2.2-5b Subsurface Soil Sample Mercury Results
4.2.2-5c Surface Soil Extent of Mercury Impacts
4.2.2-5d Subsurface Soil Extent of Mercury Impacts
4.2.2-6a Surface Soil Sample Zinc Results
4.2.2-6b Subsurface Soil Sample Zinc Results
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LIST OF FIGURES
4.2.2-7a Surface Soil Sample Other Metals and Cyanide Results
4.2.2-7b Subsurface Soil Sample Other Metals and Cyanide Results
4.2.2-7c Surface Soil Extent of Other Metals Impacts
4.2.2-7d Subsurface Soil Extent of Other Metals Impacts
4.2.2-8a Surface Soil Sample VOC Results
4.2.2-8b Subsurface Soil Sample VOC Results
4.2.2-8c Subsurface Soil Extent of VOC Impacts
4.2.2-9a Surface Soil Sample SVOC Results
4.2.2-9b Subsurface Soil Sample SVOC Results
4.2.2-9c Surface Soil Extent of SVOC Impacts
4.2.2-9d Subsurface Soil Extent of SVOC Impacts
4.2.2-10a Surface Soil Sample PCB Results
4.2.2-10b Subsurface Soil Sample PCB Results
4.2.2-10c Surface Soil Extent of PCB Impacts
4.2.2-10d Subsurface Soil Extent of PCB Impacts
4.2.2-11a Surface Soil Sample Pesticide Results
4.2.2-11b Subsurface Soil Sample Pesticide Results
4.2.2-12 Surface Soil Sample Asbestos Results
4.2.2-13a Surface Soil Sample TCLP and SPLP Results
4.2.2-13b Subsurface Soil Sample TCLP and SPLP Results
4.2.2-14a Surface Soil Sample Arsenic Results – Residential Area/Off-site Area
4.2.2-14b Surface Soil Extent of Arsenic Impacts – Residential Area/Off-site Area
4.2.2-15a Surface Soil Sample Cadmium Results Residential Area/Off-site Area
4.2.2-15b Surface Soil Extent of Cadmium Impacts Residential Area/Off-site Area
4.2.2-16a Surface Soil Sample Lead Results Residential Area/Off-site Area
4.2.2-16b Surface Soil Extent of Lead Impacts Residential Area/Off-site Area
4.2.2-17a Surface Soil Sample Zinc Results Residential Area/Off-site Area
4.2.2-17b Surface Soil Extent of Zinc Impacts Residential Area/Off-site Area
4.2.2-18a Surface Soil Sample Manganese Results - Residential Area/Off-site Area
4.2.2-18b Surface Soil Extent of Manganese Impacts - Residential Area/Off-site Area
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LIST OF FIGURES
4.2.3-1 Building Material Sampling Locations
4.2.3-2 Building Material Arsenic Results
4.2.3-3 Building Material Cadmium Results
4.2.3-4 Building Material Lead Results
4.2.3-5 Building Material Mercury Results
4.2.3-6 Building Material Zinc Results
4.2.3-7 Building Material Other Metals Results
4.2.3-8 Building Material SVOC Results
4.2.3-9 Building Material Pesticide and PCB Results
4.2.3-10 Building Material Asbestos Results
4.2.4-1 Pile Sampling Locations
4.2.4-2 Pile Arsenic Results
4.2.4-3 Pile Cadmium Results
4.2.4-4 Pile Lead Results
4.2.4-5 Pile Mercury Results
4.2.4-6 Pile Zinc Results
4.2.4-7 Pile Other Metals Results
4.2.4-8 Pile SVOC Results
4.2.4-9 Pile Pesticide and PCB Results
4.2.4-10 Pile Asbestos Results
4.2.5-1 Groundwater Well Locations
4.2.5-2 Groundwater Exceedance Summary
4.2.5-3 Dissolved Arsenic in WBZ1 Groundwater December 2008
4.2.5-4 Dissolved Arsenic in WBZ1 Groundwater June 2009
4.2.5-5 Dissolved Arsenic in WBZ2 Groundwater December 2008
4.2.5-6 Dissolved Arsenic in WBZ2 Groundwater June 2009
4.2.5-7 Dissolved Cadmium in WBZ1 Groundwater December 2008
4.2.5-8 Dissolved Cadmium in WBZ1 Groundwater June 2009
4.2.5-9 Dissolved Cadmium in WBZ2 Groundwater December 2008
4.2.5-10 Dissolved Cadmium in WBZ2 Groundwater June 2009
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LIST OF FIGURES
4.2.5-11 Dissolved Lead in WBZ1 Groundwater December 2008
4.2.5-12 Dissolved Lead in WBZ1 Groundwater June 2009
4.2.5-13 Dissolved Lead in WBZ2 Groundwater December 2008
4.2.5-14 Dissolved Lead in WBZ2 Groundwater June 2009
4.2.5-15 Dissolved Zinc in WBZ1 Groundwater December 2008
4.2.5-16 Dissolved Zinc in WBZ1 Groundwater June 2009
4.2.5-17 Dissolved Zinc in WBZ2 Groundwater December 2008
4.2.5-18 Dissolved Zinc in WBZ2 Groundwater June 2009
4.2.5-19 Dissolved Cobalt in WBZ1 Groundwater December 2008
4.2.5-20 Dissolved Cobalt in WBZ1 Groundwater June 2009
4.2.5-21 Dissolved Cobalt in WBZ2 Groundwater December 2008
4.2.5-22 Dissolved Cobalt in WBZ2 Groundwater June 2009
4.2.5-23 Dissolved Manganese in WBZ1 Groundwater December 2008
4.2.5-24 Dissolved Manganese in WBZ1 Groundwater June 2009
4.2.5-25 Dissolved Manganese in WBZ2 Groundwater December 2008
4.2.5-26 Dissolved Manganese in WBZ2 Groundwater June 2009
4.2.5-27 Maximum VOC Results in Groundwater
4.2.6-1 Surface Water Sampling Locations
4.2.6-2 Maximum Surface Water Arsenic Results
4.2.6-3 Maximum Surface Water Cadmium Results
4.2.6-4 Maximum Surface Water Lead Results
4.2.6-5 Maximum Surface Water Mercury Results
4.2.6-6 Maximum Surface Water Zinc Results
4.2.6-7 Maximum Surface Water Other Metals Results
4.2.7-1 Asbestos Air Sampling Locations
4.3.3-1 Southern and Slag Pile Border Areas: Soil Sampling Locations
4.3.3-2 Little Vermilion River and Slag Pile Border Areas: Monitoring Well Locations
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LIST OF TABLES
VOLUME 4
2.1.1-1 Phase I and Phase II Sample Information for OU1
2.1.2-1 Monitoring Well Construction Details
2.1.3-1 Phase I Analytical Program at OU1
2.1.3-2 Interstitial Water Level Data from OU1
2.2.1-1 Phase I and II Sample Information For All Matrices
2.2.1-2a Phase I Soil Boring Depths, Sampled Intervals, and Lithologies
2.2.1-2b Phase II Soil Boring Depths, Sampled Intervals, and Lithologies
2.2.1-3 Analytical Method Summary
2.2.2-1 Monitoring Well Installation and Development Summary
2.2.2-2 Summary of Monitoring Well Groundwater Sample Analyte Groups
2.2.2-3 Phase I and II Water Quality Parameters
2.2.2-4 Phase II Slug Test Summary
2.2.8-1 Asbestos Air Sampling Data
3.2.3-1 Summary of the Hydraulic Conductivity Testing for OU1 Wells
3.2.3-2 OU1 Water Levels in the Sampling Points and the LVR
3.3.3-1 OU2 Monitoring Well Details and WBZ Designations
3.3.3-2 OU2 Monitoring Well Depths and Quarterly Groundwater Elevations
3.3.3-3 OU2 Monitoring Well Hydraulic Conductivity Values
3.4.2-1 Site and Vicinity Geologic Units
5.1-1 Chemical Properties for Organic Contaminants of Concern
5.1.2-1 Potential Forms, Immobilization and Mobilization Mechanisms for Inorganic
Contaminants of Concern
5.4.1-1 Sequential Extraction Procedure Analytical Summary
5.4.1-2 Sequential Extraction Procedure Data Summary - Average Relative Fractions
5.4.1-3 Soil SEP Identification of Controlling Immobilization Processes and Conditions That
May Increase Inorganic Mobility
5.4.1-4 SPLP Data Summary - Terrestrial Soils
5.4.1-5 SPLP Mass Summary - Terrestrial Soils and Slag
5.4.1-6 Sediment SPLP Data Summary
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LIST OF TABLES
5.4.1-7 Specialized Leachability Procedure Results
5.4.1-8 Plant Area Soils TCLP Results
5.4.1-9 Slag Pile Area Soils TCLP Results
5.4.1-10 Sediment TCLP Results
5.5.1-1 Soil-to-Groundwater Comparison Results
5.5.1-2 Comparison of Soil-to-Groundwater Basis Values and SPLP Values
5.5.2-1 OU2 Average Groundwater Geochemistry Values
6.3.5-1 Summary of COI Exceedances for OU1 and OU2
9.5.1-1 OU1 Data Limitations and Uncertainties
9.5.1-2 OU2 Data Limitations and Potential Future Field Investigation Recommendations
VOLUME 5
4.0-1 Screening Values for Soil, Air, Groundwater, Sediment, and Surface Water Samples
4.1.2-1 Summary of Historical Analyses Conducted on Shallow Soil Samples
4.1.2-2 Summary of Historical Analyses Conducted on Deep Soil Samples
4.1.2-3 Summary of Analytical Data for Shallow Soil Samples from the Plant Area that
Exceeded Screening Values
4.1.2-4 Summary of Analytical Data for Deep Soil Samples from the Plant Area that Exceeded
Screening Values
4.1.2-5 Metals Results for Shallow Soil Samples Collected from the Plant Area
4.1.2-6 Metals Results for Deep Soil Samples Collected from the Plant Area
4.1.2-7 VOC Results for Shallow Soil Samples Collected from the Plant Area
4.1.2-8 VOC Results for Deep Soil Samples Collected from the Plant Area
4.1.2-9 SVOC Results for Shallow Soil Samples Collected from the Plant Area
4.1.2-10 SVOC Results for Deep Soil Samples Collected from the Plant Area
4.1.2-11 PCB Results for Shallow Soil Samples Collected from the Plant Area
4.1.2-12 PCB Results for Deep Soil Samples Collected from the Plant Area
4.1.2-13 Other Inorganics Results for Shallow Soil Samples Collected from the Plant Area
4.1.2-14 Other Inorganics Results for Deep Soil Samples Collected from the Plant Area
4.1.2-15 Summary of Analytical Data for Shallow Soil Samples from the Slag Pile Area that
Exceeded Screening Values
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LIST OF TABLES
4.1.2-16 Summary of Analytical Data for Deep Soil Samples from the Slag Pile Area that
Exceeded Screening Values
4.1.2-17 Metals and Cyanide Results for Shallow Soil Samples Collected from the Slag Pile
4.1.2-18 Metals and Cyanide Results for Deep Soil Samples Collected from the Slag Pile
4.1.2-19 VOC Results for Shallow Soil Samples Collected from the Slag Pile
4.1.2-20 VOC Results for Deep Soil Samples Collected from the Slag Pile
4.1.2-21 SVOC Results for Shallow Soil Samples Collected from the Slag Pile
4.1.2-22 SVOC Results for Deep Soil Samples Collected from the Slag Pile
4.1.2-23 PCB Results for Shallow Soil Samples Collected from the Slag Pile
4.1.2-24 Pesticides Results for Shallow Soil Samples Collected from the Slag Pile
4.1.2-25 Other Inorganics Results for Shallow Soil Samples Collected from the Slag Pile
4.1.2-26 Other Inorganics Results for Deep Soil Samples Collected from the Slag Pile
4.1.3-1 Summary of Historical Analyses Conducted on Groundwater Samples
4.1.3-2 Summary of Analytical Data for Groundwater Samples from the Plant Area that
Exceeded Screening Values
4.1.3-3 Metals and Cyanide Results for Groundwater Samples Collected from the Plant Area
4.1.3-4 VOC Results for Groundwater Samples Collected from the Plant Area
4.1.3-5 SVOC Results for Groundwater Samples Collected from the Plant Area
4.1.3-6 Other Inorganics Results for Groundwater Samples Collected from the Plant Area
4.1.3-7 Summary of Analytical Data for Groundwater Samples from the Slag Pile Area that
Exceeded Screening Values
4.1.3-8 Inorganic COI Results for Groundwater Samples Collected from the Slag Pile
4.1.3-9 SVOC Results for Groundwater Samples Collected from the Slag Pile
4.1.3-10 Other Inorganics Results for Groundwater Samples Collected from the Slag Pile
4.1.4-1 Summary of Historical Analyses Conducted on Sediment Samples
4.1.4-2 Summary of Historical Analyses Conducted on Surface Water Samples
4.1.4-3 Summary of Analytical Data for Sediment Samples from the Slag Pile Area that
Exceeded Screening Values
4.1.4-4 Inorganic COI Results for Sediment Samples Collected from the Slag Pile
4.1.4-5 VOC Results for Sediment Samples Collected from the Slag Pile
4.1.4-6 SVOC Results for Sediment Samples Collected from the Slag Pile
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LIST OF TABLES
4.1.4-7 PCB Results for Sediment Samples Collected from the Slag Pile
4.1.4-8 Other Inorganic Results for Sediment Samples Collected from the Slag Pile
4.1.4-9 Summary of Analytical Data for Sediment Samples from the Little Vermilion River that
Exceeded Screening Values
4.1.4-10 Summary of Analytical Data for Surface Water Samples from the Little Vermilion River
that Exceeded Screening Values
4.1.4-11 Inorganic COI Results for Sediment Samples Collected from the Little Vermilion River
4.1.4-12 Metals and Cyanide Results for Surface Water Samples Collected from the Little
Vermilion River
4.1.4-13 VOC Results for Sediment Samples Collected from the Little Vermilion River
4.1.4-14 VOC Results for Surface Water Samples Collected from the Little Vermilion River
4.1.4-15 SVOC Results for Sediment Samples Collected from the Little Vermilion River
4.1.4-16 PCB Results for Sediment Samples Collected from the Little Vermilion River
4.1.4-17 Pesticides Results for Sediment Samples Collected from the Little Vermilion River
4.1.4-18 Other Inorganics Results for Sediment Samples Collected from the Little Vermilion
River
4.1.4-19 Other Inorganics Results for Surface Water Samples Collected from the Little Vermilion
River
4.1.7-1 Air Monitoring Results for Arsenic, Lead, and Asbestos
4.2.1-1 Current and Historical Buildings and Uses
4.2.2-1a Detected Soil Metals and Cyanide Results
4.2.2-1b Detected XRF-Screened Soil Metals and Cyanide Results
4.2.2-2 Detected Soil VOC Results
VOLUME 6
4.2.2-3 Detected Soil SVOC Results
4.2.2-4a Detected Soil PCB Results
4.2.2-4b Detected Soil PCB Results and PCB Test Kit Results
4.2.2-5 Detected Soil Pesticide Results
4.2.2-6 Detected Soil Asbestos Results
4.2.2-7 Detected Soil TCLP Metals Results
4.2.2-8a Detected Soil SPLP Metals Results – Regulatory Level SV
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LIST OF TABLES
4.2.2-8b Detected Soil SPLP Metals Results – GWSV
4.2.2-9 Detected XRF-Screened Soil Metals Results Residential Area/Off-site Area
4.2.3-1 Detected Building Material Metals and Cyanide Results
4.2.3-2 Detected Building Material VOC Results
4.2.3-3 Detected Building Material SVOC Results
4.2.3-4 Detected Building Material PCB Results
4.2.3-5 Detected Building Material Pesticide Results
4.2.3-6 Detected Building Material Asbestos Results
4.2.3-7 Detected Building Material TCLP Metals Results
4.2.4-1 Detected Pile Metals and Cyanide Results
4.2.4-2 Detected Pile VOC Results
4.2.4-3 Detected Pile SVOC Results
4.2.4-4 Detected Pile PCB Results
4.2.4-5 Detected Pile Pesticide Results
4.2.4-6 Detected Pile Asbestos Results
4.2.5-1 Summary of Groundwater Analyte Group Sampling Per Monitoring Well
4.2.5-2 Summary of MCL and RSL Exceedances in Groundwater per Monitoring Well Location
4.2.5-3 Detected Groundwater Metals and Cyanide Results
4.2.5-4 Detected Groundwater VOC Results
4.2.5-5 Detected Groundwater SVOC Results
4.2.5-6 Detected Groundwater PCB Results
4.2.5-7 Detected Groundwater Pesticide Results
4.2.6-1 Summary of Surface Water Sampling Events
4.2.6-2 Detected Surface Water Metals and Cyanide Results
4.2.6-3 Detected Surface Water VOC Results
4.2.6-4 Detected Surface Water SVOC Results
4.2.6-5 Detected Surface Water Pesticide Results
4.2.7-1 Summary of Air Asbestos Results
4.3.1-1 Summary of Constituents of Interest Exceeding Screening Values for OU1
4.3.2-1 OU2 Summary of Results
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LIST OF TABLES
4.3.3-1 Border Area List of Soil Samples and Analyte Groups
4.3.3-2 Summary of SV Exceedances in Soil Boring: Border Areas
4.3.3-3 Border Area List of Groundwater Samples and Analyte Groups
4.3.3-4 Summary of SV Exceedances in Groundwater Monitoring Wells: Little Vermilion River
and Slag Pile Border Areas
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LIST OF APPENDICES
SEE GEOSYNTEC DISK 1 OF 2
G-2-1 OU1 Boring Logs for All Borings and Monitoring Wells
G-2-2 OU1 Well Construction Logs
G-2-3 OU1 Historical Groundwater Level Data
G-2-4 OU1 Well Development Records
G-4-1a Data Validation Reports, COCs, Analytical Lab Reports
G-4-1 OU1 Soil Metals Results
G-4-2 OU1 Soil VOC Results
G-4-3 OU1 Soil SVOC Results
G-4-4 OU1 Soil PCB Results
G-4-5 OU1 Soil Pesticide Results
G-4-6 OU1 Soil Other Inorganics Results
G-4-7 OU1 Soil TCLP Results
G-4-8 OU1 Soil SEP Results
G-4-9 OU1 Groundwater Metals Results
G-4-10 OU1 Groundwater VOC Results
G-4-11 OU1 Groundwater SVOC Results
G-4-12 OU1 Groundwater PCB Results
G-4-13 OU1 Groundwater Pesticide Results
G-4-14 OU1 Groundwater Other Inorganics Results
G-4-15 OU1 Sediment Metals Results
G-4-16 OU1 Sediment VOC Results
G-4-17 OU1 Sediment SVOC Results
G-4-18 OU1 Sediment PCB Results
G-4-19 OU1 Sediment Pesticide Results
G-4-20 OU1 Sediment Other Inorganics Results
G-4-21 OU1 Sediment TCLP Results
G-4-22 OU1 Sediment SEP Results
G-4-23 OU1 Sediment AVS-SEM Results
G-4-24 OU1 Surface Water Metals Results
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LIST OF APPENDICES
G-4-25 OU1 Surface Water VOC Results
G-4-26 OU1 Surface Water SVOC Results
G-4-27 OU1 Surface Water PCB Results
G-4-28 OU1 Surface Water Pesticide Results
G-4-29 OU1 Surface Water Other Inorganics Results
G-5-1 SPLP Scatter Plots (former Appendix B)
G-5-2 Leachability Test Results
SEE SULTRAC DISK 1 OF 2
S-1 Phase I and Phase II Soil Boring Logs
S-2 Standard Operating Procedures for Field Work
S-3 Phase I and Phase II Monitoring Well Installation Logs
S-4 Hvorslev Method (Details and Calculations)
S-5 Ecological Habitat Evaluation, Technical Memorandum, Internal Draft
S-6 Monitoring Well and Piezometer Construction Logs
S-7 Natural Gamma Downhole Logs
S-8 Data Validation Reports
S-9 US EPA FIELDS Report Detailing XRF Correlations
SEE SULTRAC DISK 2 OF 2
S-10 Soil Metals Results Data
S-11 Soil VOC Results Data
S-12 Soil SVOC Results Data
S-13 Soil PCB Results Data
S-14 Soil Pesticide Results Data
S-15 Soil Asbestos Results Data
S-16 Soil TCLP Metals Results Data
S-17 Soil SPLP Metals Results Data – Regulatory Level SV
S-18 Soil SPLP Metals Results Data – GWSV
S-19 Background Soil Metals Results Data
S-20 Background Soil SVOC Results Data
S-21 Building Materials Metals Results Data
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LIST OF APPENDICES
S-22 Building Materials VOC Results Data
S-23 Building Materials SVOC Results Data
S-24 Building Materials PCB Results Data
S-25 Building Materials Pesticide Results Data
S-26 Building Materials Asbestos Results Data
S-27 Building Materials TCLP Metals Results Data
S-28 Pile Metals Results Data
S-29 Pile VOC Results Data
S-30 Pile SVOC Results Data
S-31 Pile PCB Results Data
S-32 Pile Pesticide Results Data
S-33 Pile Asbestos Results Data
S-34 Groundwater Metals Results Data
S-35 Groundwater Metals Results, Figures 1 through 36
S-36 Groundwater Other Metals Results, Figures 1 through 6
S-37 Groundwater VOC Results Data
S-38 Groundwater VOC Results, Figures 1 through 4
S-39 Groundwater SVOC Results Data
S-40 Groundwater PCB Results Data
S-41 Groundwater Pesticide Results Data
S-42 Surface Water Metals Results Data
S-43 Surface Water VOC Results Data
S-44 Surface Water SVOC Results Data
S-45 Surface Water PCB Results Data
S-46 Surface Water Pesticide Results Data
SEE GEOSYNTEC DISK 2 OF 2
Appendix RA Final Risk Assessment
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ACRONYMS AND ABBREVIATIONS
μg/kg Microgram per Kilogram
μg/L Microgram per Liter
μg/m3 Microgram per Cubic Meter
µm Micron or Micrometer
ABS Activity-Based Sampling
ADD Average Daily Dose
AE Assessment Endpoint
AES Atomic Emission Spectroscopy
AL Action Level
ALM Adult Lead Model
ANOVA Analysis of Variance
AOC Administrative Order on Consent
ASAOC Administrative Settlement Agreement and Order on Consent
ASO Abandoned Sewer Outfall
AST Aboveground Storage Tank
ASTM American Society for Testing and Materials International
ATSDR Agency for Toxic Substance and Disease Registry
ATV All-Terrain Vehicle
AVS Acid Volatile Sulfides
BAR Biological Assessment Report
BERA Baseline Ecological Risk Assessment
bgs Below Ground Surface
BTAG US EPA Region 9 Biological Technical Assistance Group
BTEX Benzene, Toluene, Ethylbenzene, and Xylene
BTV Background Threshold Value
CalEPA California Environmental Protection Agency
Carus Carus Chemical Company
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ACRONYMS AND ABBREVIATIONS
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
CFR Code of Federal Regulations
CLP Contract Laboratory Program
cm Centimeter
cm/s Centimeter per Second
COC Constituent of Concern
COI Chemicals of Interest
Consensus Document “Technical Approach Consensus Document, Human Health and Ecological
Risk Assessments”
COPC Constituent of Potential Concern
COPEC Chemical of Potential Ecological Concern
CRQL Contract-Required Quantitation Limit
CSM Conceptual Site Model
CSO Combined Sewer Overflow
CTE Central Tendency Exposure
cVOC Chlorinated Volatile Organic Compound
CWA Clean Water Act
DCE Dichloroethene
DO Dissolved Oxygen
DQO Data Quality Objective
Ds Simpson’s Index of Diversity
EA Exposure Area
EF Exposure Frequency
ELCR Excess Lifetime Cancer Risk
EPC Exposure Point Concentration
ERA Ecological Risk Assessment
ESL Ecological Screening Level (US EPA Region 5)
ERT Emergency Response Team
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ACRONYMS AND ABBREVIATIONS
ESV Ecological Screening Value
ET Exposure Time
f/cc Fiber per Cubic Centimeter
Fibers/mL Fibers per Milliliter
FCM Food Chain Model
fIBI Fish Community Index of Biotic Integrity
FIELDS Field Environmental Decision Support
FS Feasibility Study
FSP Field Sampling Plan
ft2 Square Foot
ft/ft Foot per Foot
g/cc Grams per Cubic Centimeter
Geosyntec Geosyntec Consultants
GPM Gallons per Minute
GPS Global Positioning System
GWSV Groundwater Screening Value
H’ Shannon Weiner Diversity Index
HEAST Health Effects Assessment Summary Table
HHRA Human Health Risk Assessment
HI Hazard Index
HQ Hazard Quotient
I&M Illinois and Michigan
IBI Index of Biotic Integrity
ICP Inductively Coupled Plasma
ICRR Illinois Central Railroad
IDNR Illinois Department of Natural Resources
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ACRONYMS AND ABBREVIATIONS
IDPH Illinois Department of Public Health
IEPA Illinois Environmental Protection Agency
IEUBK Integrated Exposure Uptake Biokinetic Model
IRIS Integrated Risk Information System
IRSL Industrial Regional Screening Level
ISGS Illinois State Geological Survey
ISO International Organization for Standardization
IURLTL Less-Than-Lifetime Inhalation Unit Risk
IUR Inhalation Unit Risk
IWQS Illinois Water Quality Standard
Kd Potential for Adsorption
KH Henry's Law Constant
KOC Adsorption Coefficient for Organic Carbon
KOW Octanol-Water Partition Coefficient
LNAPL Light Non-Aqueous Phase Liquid
LOAEL Lowest Observed Adverse Effects Level
LRM LaSalle Rolling Mill
LVR Little Vermilion River
MBI Macroinvertebrate Biotic Integrity
MCE Mixed Cellulose Ester
MCL Maximum Contaminant Level
mIBI Macroinvertebrate Community Index of Biotic Integrity
MEK 2-Butanone (Methyl Ethyl Ketone)
mg/kg Milligram per Kilogram
mg/L Milligram per Liter
mm Millimeter
MOU Memorandum of Understanding
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ACRONYMS AND ABBREVIATIONS
MRL Minimal Risk Level
MS Matrix Spike
MSD Matrix Spike Duplicate
msl Mean Sea Level
mV Millivolt
MW Monitoring Well
NAD North American Datum
NGVD National Geodetic Vertical Datum
NOAA National Oceanic and Atmospheric Administration
NIOSH National Institute for Occupational Safety and Health
NOAEL No Observable Adverse Effects Level
NPDES National Pollutant Discharge Elimination System
NPL National Priorities List
NRCS Natural Resource Conservation Service
NRWQC National Recommended Water Quality Criteria
NWI National Wetland Inventory
OCL Organochlorine
ORP Oxidation Reduction Potential
OSHA Occupational Safety and Health Administration
OU Operable Unit
OU1 Operable Unit 1
OU2 Operable Unit 2
Pmc Bond Formation of the McLeansboro Group
PAH Polynuclear Aromatic Hydrocarbon
PCB Polychlorinated Biphenyl
PCE Tetrachloroethene
PDC Pyridine Dicarboxylic Acid
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ACRONYMS AND ABBREVIATIONS
PEC Probable Effects Concentration
PID Photoionization Detector
PPE Personal Protective Equipment
ppm Part per Million
ppmv Part per Million by Volume
PPRTV Provisional Peer Reviewed Toxicity Value
PRG Preliminary Remediation Goal
PRP Potentially Responsible Party
PSI Preliminary Site Investigation
PTFE Polytetrafluoroethylene
PVC Polyvinyl Chloride
Qaf Quaternary Age (Late Holocene) Artificial Fill
QAPP Quality Assurance Project Plan
QC Quality Control
Qe Equality Formation of the Quaternary System
Qly Lemont Formation of the Quaternary System
RA Risk Assessment
RAC Remedial Action Contract
RAFS Releasable Asbestos Field Sampler
RAGS Risk Assessment Guidance for Superfund
RAT Rapid Assessment Tool
RCRA Resource Conservation and Recovery Act
RfC Reference Concentration
RfD Reference Dose
RI Remedial Investigation
RME Reasonable Maximum Exposure
RO Remediation Objective
ROD Record of Decision
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ACRONYMS AND ABBREVIATIONS
RRSL Residential Regional Screening Level
RSL Regional Screening Level
SAP Sampling and Analysis Plan
SB Soil Boring
SEM Simultaneously Extracted Metals
SEP Sequential Extraction Procedure
SF Slope Factor
SLERA Screening Level Ecological Risk Assessment
SMDP Scientific Management Decision Point
SOP Standard Operating Procedure
SOW Statement of Work
SPLP Synthetic Precipitation Leaching Procedure
SSI Screening Site Inspection
SSL Soil Screening Level
START Superfund Technical Assessment and Response Team
SU Standard Unit
SV Screening Value
SVOC Semivolatile Organic Compound
SW ESV Surface Water Ecological Screening Value
SWSV Surface Water Screening Value
TACO Tiered Approach to Corrective Action Objectives
TAL Target Analyte List
TCE Trichloroethene
TCL Target Compound List
TCLP Toxicity Characteristic Leaching Procedure
TEC Threshold Effects Concentration
TEM Transmission Electron Microscopy
TOC Total Organic Carbon
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ACRONYMS AND ABBREVIATIONS
TR Target Risk
TRV Toxicity Reference Value
UCL Upper Confidence Limit
URF Unit Risk Factor
USACE United States Army Corps of Engineers
USDA United States Department of Agriculture
US EPA United States Environmental Protection Agency
USFWS United States Fish and Wildlife Service
VC Vinyl Chloride
VDEQ Virginia Department of Environmental Quality
VF Volatilization Factor
VOC Volatile Organic Compound
WA Work Assignment
WBZ Water-Bearing Zone
Weston Weston Solutions, Inc.
XRF X-Ray Fluorescence
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EXECUTIVE SUMMARY
The Matthiessen and Hegeler Zinc Company Site (Site) located in LaSalle, LaSalle County, Illinois, is a
former zinc smelting and rolling facility listed on the National Priorities List (NPL). The United States
Environmental Protection Agency (US EPA) and the potentially responsible parties (PRP) are addressing
the Site through a remedial investigation (RI) and feasibility study (FS). This RI report presents the
results of the RI as required under an Administrative Settlement Agreement and Order on Consent
(ASAOC), Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
Docket No. V-W-06-C-856 dated October 6, 2006, between US EPA Region 5 and Carus Corporation
and Carus Chemical Company (Carus). This report characterizes the nature and extent of risks posed by
the Site and documents the data collection efforts and analyses performed that will support the
preparation of the FS.
For the RI/FS, the Site was divided into two operable units (OU). On OU1, Geosyntec Consultants
(Geosyntec) is conducting RI/FS activities on behalf of Carus. On OU2, US EPA’s contractor, SulTRAC,
is conducting RI/FS activities. This RI report was prepared jointly by Geosyntec and SulTRAC.
OU1 occupies about 47 acres and was divided into three areas for the RI: the Carus Plant Area, the Slag
Pile Area, and the Little Vermilion River (LVR). For over 90 years and continuing today, the Carus Plant
has manufactured potassium permanganate and other specialty chemicals. These operations are not
related to the contamination under investigation. The main feature in the Slag Pile Area is a waste pile,
approximately 3,000 feet (ft) long and 80 to 90 ft tall, resulting from the former smelti