REMEDIAL ACTION OPTIONS REPORT FORMER GEHL COMPANY PROPERTIES, TID #12 WEST BEND, WISCONISN

Transcription

1 REMEDIAL ACTION OPTIONS REPORT FORMER GEHL COMPANY PROPERTIES, TID #12 WEST BEND, WISCONISN January 27, 2012 Prepared For: City of West Bend Department of Community Development 1115 South Main Street West Bend, Wisconsin Prepared By: Tetra Tech GEO 175 North Corporate Drive, Suite 100 Brookfield, Wisconsin Project No WDNR BRRTS # WDNR FID #

2 CERTIFICATIONS I, Daniel L. Morgan, hereby certify that I am a registered professional engineer in the State of Wisconsin, registered in accordance with the requirements of ch. A-E 4, Wis. Adm. Code; that this document has been prepared in accordance with the Rules of Professional Conduct in ch. A- E 8, Wis. Adm. Code; and that, to the best of my knowledge, all information contained in this document is correct and the document was prepared in compliance with all applicable requirements in chs. NR 700 to 726, Wis. Adm. Code. 01/27/12 Daniel L. Morgan, P.E. Date Associate, Senior Engineer I, Michael R. Noel, hereby certify that I am a scientist as that term is defined in s. NR (3), Wis. Adm. Code, and that, to the best of my knowledge, all of the information contained in this document is correct and the document was prepared in compliance with all applicable requirements in chs. NR 700 to 726, Wis. Adm. Code. 01/27/12 Michael R. Noel, P.G. Date Vice President, Principal Hydrogeologist

3 TABLE OF CONTENTS Section No. and Title Page LIST OF FIGURES... iv LIST OF TABLES... v LIST OF APPENDICES... vi 1.0 EXECUTIVE SUMMARY BACKGROUND INFORMATION Site Information Site Background Regulatory Status Nature and Extent of Contamination Geology and Hydrogeologic Characteristics INTRODUCTION Media Requiring Remediation Migration and Exposure Pathways Complexity of the Site and Legal Requirements Preparation by Qualified Persons DEFINTION AND ISOLATION OF AREAS FOR FURTHER EVALUATION Isolation of Contaminated Soil Areas Site Wide Area Arsenic and Mercury West Plant North Lead Maintenance Garage South Lead MW-2 to MW-4 Area Lead Maintenance Garage South PVOCs MW-4 Area PVOCs MW-2 to MW-4 to GP-6 Area Benzo(a)pyrene West Plant North Benzo(a)pyrene West Plant Center Benzo(a)pyrene West Plant North CVOCs West Plant Center CVOCs West Plant Southeast Loading Docks CVOCs Maintenance Garage East CVOCs i

4 ii TABLE OF CONTENTS 4.2 Isolation of Groundwater Contamination Areas MW-6 West Plant Southeast Loading Docks MW-4 GPTW-2B Maintenance Garage South MW-15 West Plant North Boundary West Plant North MW-52R Off Site West West Plant South Sump West Half Engineering Building Indiana Avenue at Milwaukee River IDENTIFICATION AND SCREENING OF TECHNOLOGIES Remedial Action Objectives Cleanup Criteria Soil Technology Screening No Action In-Place Capping Consolidation On Site and Capping Excavation and On-Site Landfarming Chemical Oxidation via In-Situ Soil Mixing Excavation and Off-Site Disposal In-Situ Soil Vapor Extraction Electrical Resistance Heating Comparative Analysis Summary Soil Groundwater Technology Screening No Action Monitored Natural Attenuation Groundwater Pump and Treat In-Situ Bioremediation In Situ Chemical Oxidation Comparative Analyses Summary Groundwater DETAILED ANALYSIS OF ALTERNATIVES Detailed Analysis of Soil Alternatives Maintenance Garage South & MW-4 Area West Plant North West Plant Southeast Loading Docks Maintenance Garage East Detailed Analysis of Groundwater Alternatives Alternative GW-1: No Action Alternative GW-2: Groundwater Pump and Treat with MNA... 32

5 TABLE OF CONTENTS Alternative GW-3: Groundwater Pump and Treat Alternative GW-4: Bioremediation with MNA CONCLUSIONS Selected Soil Remedial Alternative Maintenance Garage South & MW-4 Area West Plant North West Plant Southeast Loading Docks Maintenance Garage East Selected Groundwater Remedial Alternative iii

6 LIST OF FIGURES LIST OF FIGURES Figure 1. Site Location Map Figure Aerial Photo of TIF District #12 Figure 3. Summary of Impacts in Soil Figure 4. Chlorinated VOCs Impacts in Soil Figure 5. West Plant Loading Docks Area Layout and Chlorinated VOCs in Soil Data Figure 6. Trichloroethene Impacts in Groundwater Figure 7. Vinyl Chloride Impacts in Groundwater Figure 8. Cis-1,2-Dichloroethene Impacts in Groundwater Figure 9. 1,1-Dichloroethene Impacts in Groundwater Figure 10. 1,1,1-Trichloroethane Impacts in Groundwater Figure 11. Geologic Cross-Section A-A Figure 12. Water Table Map March 28, 2011 Figure 13. Soil Gas Probes Locations and Trichloroethene Results Figure 14. Alternative GW-2 Capture Zones Figure 15. Alternative GW-3 Captures Zones Figure 16. Alternative GW-4 Bioremediation Injection Well Locations iv

7 LIST OF TABLES LIST OF TABLES Table 1. Summary of Soil Samples VOCs Analytical Results Table 2. Summary of Groundwater Samples VOCs Analytical Results Table 3. Identified Soil Areas at Former Gehl Site Table 4. Identified Groundwater Areas at Former Gehl Site Table 5. Soil Remedial Action Decision Matrix Table 6. Groundwater Remedial Action Decision Matrix Table 7. Summary of Remedial Alternative Costs v

8 LIST OF APPENDICES LIST OF APPENDICES Appendix A. Reference Figures Appendix B. USEPA Soil Cleanup Standards Appendix C. Alternative Cost Estimates vi

9 SECTION EXECUTIVE SUMMARY This identification and evaluation of remedial action options (RAO) was prepared for the City of West Bend in compliance with NR 722 of the Wisconsin Administrative Code for the Former Gehl Company Properties site. As the responsible party, the City of West Bend shall select appropriate remedial actions to address soil and groundwater contamination present in the subsurface to protect human health and the environment. The remediation shall occur to cause soil and groundwater to meet the cleanup standards contained in the NR 700 series regulations and chapter NR 140 of the Wisconsin Administrative Code. For soil remedial action options, eight separate distinct soil areas on the site were categorized based on contaminant. These eight areas were then analyzed based on contaminant to determine if they merited more detailed consideration. Five of the eight areas were selected for further analyses. Eight soil remedial technologies were screened for use at the site and scored using NR 722 criteria. Of these eight, four alternatives, including the No Action alternative, were selected for further consideration. In-place capping (Alternative S-2) is recommended as the selected remedial action option for soil at the five site areas receiving detailed analyses. This RAO meets the current City use of the site, is economical, and is protective of human health and the environment. For groundwater remedial action options, a single combined site-wide groundwater contaminant area was selected for detailed analyses. Seven groundwater remedial action options were screened for use at the site and scored using NR 722 criteria. Of these seven, four alternatives, including the No Action alternative, were selected for further consideration. Bioremediation with MNA (Alternative GW-4) is recommended as the selected remedial action option for groundwater at the site. This RAO is protective of human health and the environment and is the lowest cost option after the No Action alternative. This RAO meets the current City use of the site and provides flexibility for future site uses. The content of this report includes the following sections: 2.0 Background Information 3.0 Introduction 4.0 Definition and Isolation of Areas for Further Evaluation 5.0 Identification and Screening of Remedial Technologies 6.0 Detailed Analyses of Alternatives 7.0 Conclusions The purpose of this submittal is to gain Wisconsin Department of Natural Resources review and comment prior to implementation of the selected remedial options. 1

10 SECTION BACKGROUND INFORMATION 2.1 Site Information 1. Project Title: Former Gehl Co. Tax Incremental Finance District #12 Remedial Action Options Report 2. Name of Facility: Former Gehl Co. Tax Incremental Finance District #12 3. Facility Address: 143 East Water Street, West Bend, WI Facility Location: West ½ of the Northwest ¼ and the Northwest ¼ of the Southwest ¼ of Section 13, Township 11 North, Range 19 East, City of West Bend, Washington County, Wisconsin (Figure 1 Site Location Map). 5. WTM91 Coordinates (x,y): , BRRTS Number: FID Number: Site Contact: Julie Cayo, Department of City Development, cayoj@ci.west-bend.wi.us 9. Consultant: Tetra Tech GEO, 175 N. Corporate Drive, Suite 100, Brookfield, WI 53045, Michael Noel, P.G., Project Manager, , ext. 223, mike.noel@tetratech.com Daniel L. Morgan, P.E., Design Engineer, , ext. 269, dan.morgan@tetratech.com Mark A. Manthey, P.G., Senior Hydrogeolgist, , ext. 271, mark.manthey@tetratech.com. 2.2 Site Background The Former Gehl site consists of four properties. The subject properties are shown on Figure 2 and are described below: 1. The property containing the Gehl Co. former manufacturing plant and corporate offices located at 143 East Water Street, which is referred to as the West Plant. 2. The 306 South Forest Avenue property located south of the West Plant property. A former City of West Bend Maintenance Garage is located on the north end of the property. A wastewater treatment plant and municipal incinerator operated by the City of West Bend were located on the south side of the property. The wastewater treatment plant and incinerator structures are no longer present. The south end of the property is currently vacant ( Vacant Land ) but was used as an open storage area by Gehl Co. after the wastewater treatment plant and incinerator structures were removed. 3. The property containing the Gehl Co. engineering and research building at 145 South Forest Avenue (Engineering Building property). 2

11 3 SECTION 2 The Former Gehl Company site is in the process of redevelopment. The southern portion of the 306 South Forest Avenue property is being redeveloped with three new one story buildings to be used for apartment nursing home residences and adjacent parking. The Maintenance Garage and West Plant are to be demolished with the floor slabs left in place. The Engineering Building is also planned for demolition, but is currently in use for storage. 2.3 Regulatory Status The WDNR Remediation and Redevelopment Program is the agency with jurisdiction over the investigation and remediation of the soil and groundwater impacts. Additional information on the regulatory status of the facility is listed below: 1. Remediation Activity Type: LUST Leaking Underground Storage Tank 2. Remediation Activity Status: Open 3. Agency Jurisdiction: WDNR, Remediation & Redevelopment 4. DNR Region: South East 2.4 Nature and Extent of Contamination The nature and extent of soil and groundwater contamination are shown on Figures 3 through 10 and in Tables 1 and 2. This data was used in defining the eight separate distinct soil areas and the site-wide groundwater area for RAO analyses. More detailed discussions on the nature and extent of contamination are contained in the list of referenced reports in Section Geology and Hydrogeologic Characteristics On the former Gehl Co. site, the unconsolidated deposits consist primarily of varying amounts of fill underlain by glacial outwash deposits which is underlain by glacial till. The fill located on the site ranges from zero to nine feet in thickness (Figure 11). The thickest fill occurs in the southeast part of the site. The fill consists of varying amounts of clay, silt, sand, and gravel, along with pieces of concrete, cinders, foundry sand, brick, and other debris at certain boreholes. Glacial outwash underlies the fill throughout the site. The outwash is made up of layers of clay, silt, sand with varying amounts of silt, and gravel. Thickness of the outwash ranges from 15 to 20 feet at the site. Glacial till, composed mostly of gray clay and silt underlies the outwash. The glacial till was only encountered in borings that were completed to depths generally deeper than 20 feet below ground surface (bgs). Bedrock was not intersected in any of the borings installed to 20 feet. Water table maps have been constructed from the measurement of water levels at 34 on- and offsite groundwater monitor wells. Groundwater occurs at depths of approximately 6 to 15 feet bgs across the site. The water table surface generally mimics topography and indicates that flow in the unconsolidated deposits is to the west, southwest and south towards the Milwaukee River (Figure 12). The horizontal hydraulic gradient ranges from 0.02 ft/ft to the west to 0.01 ft/ft to the south.

12 SECTION INTRODUCTION This identification and evaluation of remedial action options (RAO) was prepared for the City of West Bend in compliance with NR 722 of the Wisconsin Administrative Code for the Former Gehl Company Properties site. The following documents have been previously submitted by the City of West Bend to the Wisconsin Department of Natural Resources (WDNR) and form the basis for this RAO report: Phase I Environmental Site Assessment (GeoTrans Inc., September 26, 2008 Technical Memorandum, Regulated Building Materials Survey, Former City Maintenance Garage, TIF# 12, West Bend, WI (GeoTrans Inc., Jan 9, 2009) Regulated Building Materials Survey Report, Former Gehl Properties, TIF District #12, West Bend, WI (GeoTrans Inc., Nov10, 2009) Phase II Site Investigation Report (GeoTrans, Inc., Dec 4, 2009) and Response to February 16, 2010 WDNR Site Investigation Report Comments (GeoTrans, Inc., May 14, 2010) Soil Management Plan and Health & Safety Plan, Former Gehl Company Properties South Lot, (GeoTrans Inc., Apr 2010) and Response to July 22, 2010 WDNR Comments on May 27, 2010 Soil Management Plan for the South Lot (GeoTrans, Inc., Aug 4, 2010) Additional Phase II Site Investigation Activities Report (Tetra Tech GEO, July 7, 2011) 3.1 Media Requiring Remediation The media addressed in this RAO report are soil and groundwater. Vapor intrusion is considered as a potential migration pathway for both soil and groundwater contamination. Other air-related media evaluations are not considered in this RAO report, as none are apparent at the site. 3.2 Migration and Exposure Pathways The exposure pathways considered for soil and groundwater contamination are: Ingestion Inhalation Dermal contact Soil to groundwater Vapor intrusion Utility corridor migration 3.3 Complexity of the Site and Legal Requirements The Former Gehl Properties site is a complex site with multiple contaminant types and sources. This RAO report considers each known contaminant in each of the media and selects an appropriate RAO. The City of West Bend plans complete redevelopment of all site areas and desires to meet all legal requirements in completing this redevelopment. Regulatory approval and implementation of the RAOs will aid in satisfying the legal requirements for redevelopment. 4

13 SECTION Preparation by Qualified Persons The evaluation and documentation of an appropriate set of remedial action options in this RAO report has been completed by qualified persons pursuant to s. NR and is signed and sealed by Wisconsin-registered professional geologists and engineers. 5

14 4.0 DEFINTION AND ISOLATION OF AREAS FOR FURTHER EVALUATION 6 SECTION Isolation of Contaminated Soil Areas The site investigation activities have provided a list of quantified contaminated soil areas as indicated in Table 3 and Figure 3. Eight separate soil areas are listed, four with more than one contaminant of concern. Each row in Table 3 is discussed below with, where necessary, a proposed action on further, more intense RAO evaluation Site Wide Area Arsenic and Mercury Arsenic was found in every site investigation soil sample analyzed at a level above both the nonindustrial (0.039 mg/kg) and industrial (1.6 mg/kg) NR 720 Table 2 Residual Contaminant Level. Site Investigation (SI) soil samples were collected at 2-12 feet below surface grade (Reference Figure 5-4 Appendix A). Detected arsenic levels in soil ranged from 1.1 mg/kg to 5.8 mg/kg, with one higher detection at GPTW-12 ((36.1 mg/kg) a multiple contaminant area beneath the floor slab at the West Plant North area). Item 1 of the WDNR letter of February 16, 2010 commented Collect additional soil samples from 0-4 feet to determine if a direct contact threat is present on or off site. In response to this WDNR comment, replies were made on two occasions: May 14, A direct contact threat does not exist at this time. Site soils are either covered by the West Plant, Engineering Building, Maintenance Garage, concrete driveways, city streets, or base coarse sand and gravel fill. If the buildings are demolished or redevelopment activities remove the base coarse sand and gravel fill, additional soil sampling to determine the direct contact health risk will be conducted at that time. August 4, 2010 (Referring to the South Lot soils) Soil sampling efforts were designed based on the results of the Phase I ESA findings which indicated the only former site use of potential environmental concern was the part of the site used for a former waste water treatment plant. Several attempts at soil sampling were not productive because of the coarse gravelly fill (2 to 6 feet thick) and/or refusal on subsurface structures. Proposed redevelopment activities include leaving this coarse material in place and adding additional fill (1.5 feet) to bring the site to grade. The only area of identified contamination (direct contact PAHs) in the upper 4 feet will be excavated and relocated to within the footprint of a proposed on-site building structure which will serve as an engineered barrier. Nearly 90 percent of the site will be covered with engineered barriers consisting of buildings, parking lots, roadways and sidewalks. The combination of clean fill and engineered barriers provides an additional measure of protection even though no recognized environmental conditions were identified across the majority of the site. Mercury was found in five soil samples, three at four foot below grade and two at eight foot below grade (Reference Figure 2, Appendix A). Mercury was not found above the NR 140 enforcement standard in any site groundwater sample and it is concluded that the soil remedial actions for arsenic will suffice for mercury.

15 7 SECTION Selected Remedial Action Option Arsenic South Lot The selected remedial action option for the South Lot, the gravel area bounded by the southern edge of existing residential lots along Linwood Terrace to the north, Indiana Avenue to the east, the park strip along the Milwaukee River to the south, and Forest Avenue to the west, is detailed in the April 2010 Soil Management Plan and Health & Safety Plan, Former Gehl Company Properties. The remedial action option includes a four-foot thick soil barrier overlain by slab-ongrade buildings, parking areas, and finished landscaping Selected Remedial Action Option Arsenic Open Gravel Area South of Maintenance Garage The selected remedial action option for the open gravel area south of the Maintenance Garage will mirror that of the South Lot. No soils will be permitted to leave the site. A four-foot thick layer of existing gravel soils overlain by added clean fill and finished landscaping will be used to address the direct contact issue. If a portion of this area is redeveloped, the four-foot thick soil barrier in combination with other engineered barriers will be maintained to address the direct contact issue Selected Remedial Action Option Arsenic Maintenance Garage, West Plant, and Engineering Building The selected remedial action option for the Maintenance Garage, West Plant, and Engineering Building will vary with the site redevelopment. If the building floor slabs remain in place, with or without the remaining building structure, these floor slabs will constitute an adequate engineered barrier for direct contact for the soils beneath them. If the floor slabs are removed, additional remedial action options will be considered at that time. Either excavation and landfill disposal or installation of an adequate direct contact barrier will be used to address the direct contact issue. No other remedial action options beyond those listed above are contemplated for the Site-Wide Area Arsenic soil contamination issue. Further evaluation of RAOs for arsenic is not required West Plant North Lead Lead was found in only two soil samples analyzed (out of nine collected in the West Plant North area), one at a level above the non-industrial (50 mg/kg, at GPTW-16 (163 mg/kg at 4 feet below surface grade)) and industrial (500 mg/kg, at GPTW-12 (1070 mg/kg at 2 feet below surface grade)) NR 720 Table 2 Residual Contaminant Levels (RCLs). Site Investigation soil samples were collected at 2-12 feet below surface grade (Reference Figure 5-4 Appendix A). Detected lead levels were found in every soil sample collected in the West Plant North area. However, at the two locations where lead exceeded the NR 720 RCLs, deeper soil samples, above the water table, yielded lead results above the NR 720 non-industrial RCL. The selected remedial action option for the West Plant North Lead area will vary with the site redevelopment. If the building floor slab remains in place, with or without the remaining

16 SECTION 4 building structure, the floor slab will constitute an adequate engineered barrier for the soils beneath it. If the floor slab is removed, additional remedial action options will be considered at that time. Either excavation and landfill disposal or installation of an adequate direct contact barrier will be used to address the direct contact issue for lead at the West Plant North area Maintenance Garage South Lead Lead was found in scattered soil sample locations above the non-industrial RCL (Reference Figure 5-4, Appendix A). At only one soil sample location (GPTW-3C) did the coincident deeper soil sample also contain lead above the non-industrial RCL. The surface area of the lead impacted soils is limited to an approximate 100-foot diameter circle immediately southwest (towards the river) of two abandoned in place (AIP) gasoline underground storage tanks (USTs). The selected remedial action option for the Maintenance Garage South Lead area will vary with the site redevelopment. If this area remains open space, the remedial action option will mirror that of the South Lot. No soils will be permitted to leave the site. A four-foot thick layer of existing gravel soils overlain by added clean fill and finished landscaping will be used to address the direct contact issue. If this area is redeveloped and the soils are undisturbed, the four-foot thick soil barrier in combination with other engineered barriers will be maintained to address the direct contact issue. If the Maintenance Garage is demolished, and the AIP USTs are removed, a soil clean up may be initiated to allow a new site use. In this instance, it is likely that excavation and landfill disposal of a portion or all of the lead contaminated soils would occur MW-2 to MW-4 Area Lead Lead was found in scattered soil sample locations above the non-industrial RCL. At MW-2 on the southeast edge of the area, both soil sample (4 at 626 mg/kg and 8 at 278 mg/kg) lead results exceeded the industrial RCL (50 mg/kg). The source of the lead is likely related to the former waste water treatment plant on this portion of the site (Reference Figure 5-4, Appendix A). Redevelopment of this portion of the site (south of the South Lot) for any purpose besides open landscaped area is unlikely due to the river abutting it. The selected remedial action option for the MW-2 to MW-4 Area for Lead will mirror the South Lot. No soils will be permitted to leave the site. A four-foot thick layer of existing gravel soils overlain by added clean fill and finished landscaping will be used to address the direct contact issue. No other remedial action options beyond those listed above are contemplated for the lead soil contamination issue. Further evaluation of RAOs for lead is not required. 8

17 SECTION Maintenance Garage South PVOCs Gasoline-related contaminants were found in soil samples proximate to two AIP gasoline USTs in this area (Reference Figure 5-1, Appendix A). Due to the potential migration of the petroleum-related VOCs (PVOCs) to groundwater and the levels of PVOCs found, further detailed evaluation of RAOs for PVOCs in this area is warranted and is found in the Section MW-4 Area PVOCs Gasoline-related contaminants were found in soil samples proximate to MW-4. Due to the potential migration of the PVOCs to groundwater and the levels of PVOCs found, further detailed evaluation of RAOs for PVOCs at MW-4 is warranted and is found in the Section MW-2 to MW-4 to GP-6 Area Benzo(a)pyrene Benzo(a)pyrene was found above the generic non-industrial RCL at 7 of 18 sample locations at varying depths (Reference Figure 5-3, Appendix A). The immobility of benzo(a)pyrene in soil and the depths to contamination allow the following; The selected remedial action option for benzo(a)pyrene for the South Lot portion of the MW-2 to MW-4 to GP-6 area is detailed in the April 2010 Soil Management Plan and Health & Safety Plan, Former Gehl Company Properties. The remedial action option includes a four-foot thick soil barrier overlain by slab-on-grade buildings, parking areas, and finished landscaping. The selected remedial action option for benzo(a)pyrene for the western open gravel area portion of the MW-2 to MW-4 to GP-6 area matches that for lead. Redevelopment of this portion of the site for any purpose besides open landscaped area is unlikely due to the river abutting it. No soils will be permitted to leave the site. A four-foot thick layer of existing gravel soils overlain by added clean fill and finished landscaping will be used to address the direct contact issue. If this area is redeveloped and the soils are undisturbed, the fourfoot thick soil barrier in combination with other engineered barriers will be maintained to address the direct contact issue West Plant North Benzo(a)pyrene Benzo(a)pyrene was found above the generic non-industrial RCL at three of five sample locations at varying depths (Reference Figure 5-3, Appendix A). The selected remedial action option for the West Plant North Benzo(a)pyrene area will vary with the site redevelopment. If the building floor slab remains in place, with or without the remaining building structure, the floor slab will constitute an adequate engineered barrier for the soils beneath it. If the floor slab is removed, additional remedial action options will be considered at that time. Either excavation and landfill disposal or installation of an adequate direct contact barrier will be used to address the direct contact issue for lead at the West Plant North area. 9

18 10 SECTION West Plant Center Benzo(a)pyrene Benzo(a)pyrene was found above the generic non-industrial RCL at two of five sample locations at varying depths (Reference Figure 5-3, Appendix A). The selected remedial action option for the West Plant Center Benzo(a)pyrene area will vary with the site redevelopment. If the building floor slab remains in place, with or without the remaining building structure, the floor slab will constitute an adequate engineered barrier for the soils beneath it. If the floor slab is removed, additional remedial action options will be considered at that time. Either excavation and landfill disposal or installation of an adequate direct contact barrier will be used to address the direct contact issue for lead at the West Plant Center area West Plant North CVOCs Chlorinated volatile organic compounds (CVOCs) contaminants were found in three of eight soil sample locations to a minimum depth of six feet below grade. At two of these sample locations, a deeper soil sample yielded non-detectable COVC results. Due to the potential migration of the CVOCs to groundwater and the levels of CVOCs found, further detailed evaluation of RAOs for CVOCs at the West Plant North Area is warranted and is found in the Section West Plant Center CVOCs CVOC contaminants were found in one of five soil sample locations. At this soil sample location (GPTW-7), a deeper soil sample yielded non-detectable CVOC results. The only CVOC detected was TCE at 32.9 ug/kg with a J laboratory qualifier. As the detected CVOC is low and its location corresponds to a Benzo(a)pyrene results requiring remediation, the remedial action option for Benzo(a)pyrene will be sufficient (see above) West Plant Southeast Loading Docks CVOCs CVOC contaminants were found in three of eleven soil sample locations (methylene chloride, a laboratory artifact, is excluded) to a minimum depth of four feet below grade. At two of these sample locations, a deeper soil sample yielded non-detectable CVOC results. Due to the potential migration of the CVOCs to groundwater and the levels of CVOCs found, further detailed evaluation of RAOs for CVOCs at the West Plant Southeast Loading Dock Area is warranted and is found in the Section Maintenance Garage East CVOCs CVOC contaminants were found in one soil sample location to a minimum depth of four feet below grade. At this location, a deeper soil sample yielded non-detectable CVOC results. Due to the potential migration of the CVOCs to groundwater and the levels of CVOCs found, further detailed evaluation of RAOs for CVOCs at the Maintenance Garage East (GPTW-4) Area is warranted and is found in the Section Isolation of Groundwater Contamination Areas The site investigation activities have provided a list of quantified contaminated groundwater areas as indicated in Table 4. Eight separate groundwater areas are listed. Each row in Table 4

19 11 SECTION 4 is discussed below with, where necessary, a proposed action on further, more detailed RAO evaluation MW-6 West Plant Southeast Loading Docks CVOC contaminants in MW-6 groundwater exceed 2,000 ug/l with the most recent sample yielding the highest total VOC level (3/1/11) to date. This area shows the greatest groundwater contamination on the site and further detailed evaluation of RAOs for CVOCs is warranted and is found in Section MW-4 GPTW-2B Maintenance Garage South PVOC contaminants in groundwater in this area are found between ug/l. PVOC contaminants are not found in down gradient monitor well MW feet away. There are no receptors present between this area and MW-1. Natural attenuation of PVOCs in groundwater will be an adequate remedial strategy and further detailed evaluation is not required MW-15 West Plant North Boundary CVOC contaminants in MW-15 groundwater approach 1,500 ug/l. MW-15 is at the north site boundary and is up gradient of known on-site CVOC sources. Contamination at this well area is likely from an off-site source. The MW-15 area is immediately up gradient of the West Plant North groundwater contaminant area and rather than consider the MW-15 area separately, remediation of MW-15 area groundwater will be included with the West Plant North area groundwater West Plant North CVOC contaminants in several monitor wells in this area range from ug/l. As noted above, contaminant levels to the immediate north are greater, although it is likely these are from an off-site source. Further detailed evaluation of RAOs for CVOCs is warranted and is found in Section MW-52R Off Site West CVOC contaminants in MW-52R groundwater approach 500 ug/l. Although this area of groundwater is outside of the Gehl site, it is down gradient of the West Plant North area. The further detailed evaluation of RAOs for the West Plant North area in Section 6.0 will include the MW-52R area West Plant South Sump CVOC contaminants in the operating basement sump located at the south end of the West Plant were found at 233 ug/l in February of This purpose of this sump is to collect storm water and groundwater from drain tile and pump the water to a storm sewer to keep the basement beneath the southern portion of the west plant dry. The water table map (Figure 12) shows an effect of the pumping from this sump. This sump and pump are included in a detailed evaluation of RAOs for CVOCs in Section 6.0.

20 SECTION West Half Engineering Building CVOC contamination beneath the west half of the Engineering Building is limited to only TCE above the NR 140 ES. The detected TCE at two temporary wells was found at 5.3 ug/l and 7.9 ug/l, slightly above the TCE ES of 5 ug/l. Down gradient monitor well MW-37 samples yielded no detection of TCE, cis 1,2 DCE, or vinyl chloride. RAOs considered for the MW-6 West Plant Southeast Loading Dock area may include remediation of groundwater at the West Half Engineering Building area. Natural attenuation is expected to be sufficient at the West Half Engineering Building area and further detailed RAO evaluation is not required Indiana Avenue at Milwaukee River CVOC contaminants in two of five temporary wells installed east of Indiana Avenue yielded total CVOC levels near or below 50 ug/l, with TCE as the largest contributor (at 40 ug/l and 10 ug/l). It was determined that the east west sewer line in this area was not a preferential migration pathway for groundwater contamination from the Gehl property. Natural attenuation is presumed adequate for this off-site area and further detailed RAO evaluation is not required. 12

21 SECTION IDENTIFICATION AND SCREENING OF TECHNOLOGIES This section presents applicable remedial action objectives (RAOs), identifies selected remedial technologies to meet the RAOs, and then evaluates and screens the technologies against selected criteria. The retained technologies are discussed in further detail in Section Remedial Action Objectives RAOs are site-specific goals established to protect human health and the environment. The RAOs provide a framework for developing and evaluating remedial action technologies and alternatives. Four RAOs have been identified for the Gehl property site. Minimize or eliminate human exposure to COCs by 1) direct contact, 2) ingestion, and 3) inhalation. Minimize or eliminate potential human exposure by vapor intrusion. Reduce the potential for COCs to leach into groundwater. Minimize or eliminate potential human exposure by VOC migration along utility corridors. 5.2 Cleanup Criteria The selected cleanup levels are designed to achieve the RAOs for the Site, to be protective of human health and the environment, and to allow the use of the Site and surrounding property in a manner consistent with their planned uses. These cleanup levels are also intended to be protective of groundwater beneath the Site. The standard selected for concentrations of VOCs in soils at the Gehl property site is the USEPA web site rais.orni.gov (Appendix B) for soils. The following tables show the cleanup criteria for selected specific VOCs. These VOCs represent the most common CVOCs and PVOCs found at the site and provide adequate cleanup targets for the site. Constituent of Concern USEPA Soil Value Ingestion (1) (ug/kg) USEPA Soil Value Inhalation (1) (ug/kg) USEPA Soil Value Soil to GW (2) (ug/kg) Benzene 1, (5.5) Ethylbenzene 1,560,000 2,000, (2,900) Naphthalene 313,000 63,000 3,100 Tetrachloroethene 123,000 1, Toluene 1,250,000 7,500, (1,500) Trichloroethene Total Xylenes 3,130, ,000 7,900 (4,100) 13

22 SECTION 5 (1) (2) The most conservative ingestion or inhalation value is used NR 720 values in parentheses The standard selected for concentrations of VOCs in groundwater at the Gehl property site is NR 140. The following tables show the cleanup criteria for selected specific VOCs. These VOCs represent the most common CVOCs and PVOCs found at the site and provide adequate cleanup targets for the site. Constituent of Concern NR 140 Groundwater Enforcement Standard (ug/l) NR 140 Groundwater Preventive Action Limit (ug/l) Benzene Ethylbenzene Naphthalene Tetrachloroethene Toluene Trichloroethene Total Xylenes Vinyl Chloride Soil Technology Screening The following subsections provide a brief discussion of the no action alternative and selected technologies that were considered as potentially viable technologies for mitigating the detected COCs and to meet the RAOs. Each of the technologies are discussed in general terms, and then evaluated against selected criteria to determine which technologies would be retained for further detailed analysis. The selected technologies are: 1. No Action; 2. In-Place Capping; 3. Consolidation On Site and Capping 4. Excavation and On-Site Landfarming; 5. Chemical Oxidation via In Situ Soil Mixing; 6. Excavation and Off-Site Disposal; 7. Soil Vapor Extraction; and, 8. Electrical Resistance Heating. 14

23 15 SECTION No Action This alternative assumes that no action will be taken and the existing site conditions will remain as they currently exist. This is selected as the first alternative to be used as a baseline for comparison of the relative improvement that will be afforded by other alternatives. This alternative requires that an institutional control (WDNR GIS registration) be implemented for the affected portion of the property. The WDNR may restrict groundwater use and will require future disruptive site activities to properly handle remaining contaminated soil. The use of WDNR GIS registration in conjunction with a WDNR-approved Operation and Maintenance Plan may be appropriate for contaminated soil areas where existing concrete slab structures covering the contaminated soils are to remain in place In-Place Capping In-place soil capping has been successfully used as for source control at numerous sites. This alternative consists of placing a clay soil or other synthetic cap over contaminated soil, much like is done for solid waste landfills. Information available from US EPA shows that capping systems reduce surface-water infiltration, control gas and odor emissions, improve aesthetics, provide a stable surface over the waste, and prevent human exposure from direct contact. Caps can range from a simple native soil cover to a multi-layer RCRA Subtitle C composite cover. RCRA multi-level cover systems must be constructed in accordance with performance standards established by the Resource Conservation and Recovery Act. These standards require the following: (1) three feet of compacted clay; (2) 80 millimeter high density polyethylene (HDPE) synthetic liner placed above the clay; (3) one foot of top soil above the synthetic liner; and (4) vegetative cover. Capping is typically used in conjunction with other remedies such as groundwater containment and control and/or institutional controls. This approach does not actively reduce source area concentrations, but works to minimize or prevent direct contact exposure to contaminants and leaching to groundwater. An operation and maintenance program would also be required after the cap is installed to monitor groundwater and maintain the cover system. This alternative would meet the RAOs for the site by preventing direct contact, preventing leaching to groundwater and reducing or eliminating potential vapor migration Consolidation On Site and Capping Rather than capping in-place, this alternative includes excavation of the contaminated soil, consolidating the soils on site at a designated location, and then capping the contaminated soil as described under the In-Place Capping alternative Excavation and On-Site Landfarming This approach consists of excavating soils in the areas exceeding cleanup goals and placing the soil in a containment area on the site. Landfarming is a volatilization and bioremediation technology, which typically involves excavation and placement of contaminated soils, sediments,

24 16 SECTION 5 or sludges into a treatment cell. The soils/sediments/sludges are periodically turned or tilled within the cell to aerate the material and thereby volatize COCs and cultivate or enhance microbial degradation of petroleum COCs. The equipment employed in landfarming is typical of that used in agricultural operations. Contaminated media is usually treated in lifts that are typically 6-18 inches thick. When the desired level of treatment is achieved, the lift is removed and a new lift is constructed. It may be desirable to only remove the top of the remediated lift, and then construct the new lift by adding more contaminated media to the remaining material and mixing. This serves to inoculate the freshly added material with an actively degrading microbial culture, and can reduce treatment times. This method usually incorporates liners and other methods to contain contaminants to the confines of the treatment cell. A landfarming site must be managed properly to prevent both on-site and off-site problems with ground water, surface water, air, or food chain contamination. This typically involves construction of a treatment cell to prevent vertical migration of COCs from contaminated media to the underlying soils and to prevent runoff of constituents during storm events. Cells can be constructed below grade or above grade and are lined with a geomembrane or clay liner to prevent infiltration into underlying soils. Typical cell designs also include a drainage layer to facilitate collection of water infiltrating through the soils. Contact water (storm water or water from decontamination of equipment) is also managed by grading or sloping the treatment cell to allow collection and transfer to contact water treatment or storage facilities. Contact water can be treated on-site or hauled off-site to a permitted facility. Adequate monitoring and environmental safeguards are required. Safeguards can include engineered controls such as perimeter fencing to minimize potential trespassing or access by unauthorized personnel. In the case of treating VOCs, air permitting may be required because of volatilization that occurs during tilling. At a minimum, a permit to install (PTI) application would be required to demonstrate that VOC emissions would not exceed emissions rates requiring treatment or control Chemical Oxidation via In-Situ Soil Mixing This technology consists of treating the soils with a chemical oxidant through soil mixing. The objective of this approach is to reduce constituent concentrations to below target levels through direct chemical reaction in contact with the soils. This in-situ approach involves the application of a chemical oxidant directly onto exposed soils. An excavator is used to open an initial excavation at one end of the proposed remediation area. Uncontaminated soils are set aside and temporarily staged in a containment cell near the excavation. The excavated cell is then used for mixing the contaminated soil at the base of the cell. Soil is treated by a combination of continual mixing and simultaneous application of the preferred treatment chemistry (chemical oxidant) by direct spraying until the desired amount of

25 17 SECTION 5 treatment chemistry is applied. The treatment cell is then expanded by moving the excavator and displacing adjacent soils into the treatment cell. This process would be repeated until the entire targeted volume has been treated. The treatment cell design allows for direct contact of the preferred treatment chemistry with the COCs within the soil matrix. The dual axis blender thoroughly turns and mixes the soil to expose the COCs to direct spraying. This allows on-site supervisory personnel to dictate exactly where the treatment chemistry is needed. This in-situ remediation approach may achieve desired reductions in one mobilization. The likely preferred treatment chemistry would involve the use of a reagent to oxidize COCs through reduction/oxidation reactions (redox). Redox reactions chemically convert hazardous contaminants to nonhazardous or less toxic compounds that are more stable, less mobile, and/or inert. Redox reactions involve the transfer of electrons from one compound to another. Specifically, one reactant is oxidized (loses electrons) and one is reduced (gains electrons). The oxidizing agents most commonly used for treatment of hazardous contaminants are ozone, hydrogen peroxide, persulfate and permanganate. Fenton s Reagents are commonly selected as a source of hydrogen peroxide for the redox reaction. Fenton s Reagent has been widely use to degrade a host of chlorinated and nonchlorinated contaminants including petroleum (diesel, gas), chlorinated hydrocarbons (PCE, TCE, and 1,2-DCE), PNA s, pesticides, and others. Traditional Fenton s Reagent utilize a transitional metal catalyst to form a hydroxyl radical. The short-lived hydroxyl radical is very effective in mineralizing contaminants. No by-products of concern are formed when using Fenton s Reagent. A modified Fenton s Reagent is similar to a traditional Fenton s Reagent except a different catalyst is used. Alternate catalysts include proprietary organic acids and chelated metals. Another process generates hydrogen peroxide from solid peroxygens that are mixed into the soil in an aqueous suspension. Once in place, the peroxygens react with water to produce hydrogen peroxide. This process does not require the injection of metal catalysts to activate the production of oxidizing radicals in the soil Excavation and Off-Site Disposal This alternative consists of excavating the soils and disposing the soils at an off-site statecertified landfill. Excavation, retrieval, and off-site disposal of contaminated soil at landfills have been performed extensively at numerous sites throughout the years. Landfilling of hazardous materials, especially hazardous wastes, is becoming increasingly difficult and expensive as a result of growing regulatory control, and can be cost-prohibitive depending on the volume of material, construction/logistical considerations, depths of the contaminated soils, soil type such as non-cohesive soils, or distance that the soils need to be transported. RCRA provides guidelines for the identification and control of hazardous waste from generation through transportation, treatment, storage, and disposal. Soils that contain RCRA-listed

26 18 SECTION 5 constituents or exhibit hazardous characteristics would have to be managed, treated, and disposed of as hazardous waste. Soils that are to be transported off-site for disposal will need to be characterized for proper treatment/disposal. If residual wastes are generated in the course of the remedial action (e.g., rinseate from decontamination of heavy equipment that comes in contact with hazardous waste) and the wastes must be transported off-site for disposal, these requirements would apply. An excavator would be used in order to remove the soil and stockpile the material for screening and segregation. Soils would be segregated based on photo-ionization detector (PID) screening into two stockpiles, one for off-site disposal and one for on-site re-use. A front-end loader or the excavator would then load the soils for off-site disposal into dump trucks for transportation to an appropriate facility In-Situ Soil Vapor Extraction Soil Vapor Extraction (SVE) is an in situ process for soil remediation where contamination is removed from soil by carrying it out through a medium such as air or steam. A negative air pressure (vacuum) is exerted on subsurface soils by a regenerative or positive-displacement blower that is connected via piping to wells or vapor-extraction points installed in the contaminated area. The extracted soil vapors are passed through an air/water separator to remove condensate from the air stream. Separated liquids and vapors are then treated as necessary. Air treatment can include carbon adsorption, catalytic oxidation, or thermal destruction. Condensate water that is recovered can be treated on-site or hauled off-site for disposal. SVE is suitable for removing a variety of contaminants that have a high vapor pressure or a low boiling point compared to water, such as chlorinated solvents and lighter petroleum compounds. SVE can handle high concentrations of contaminants, including contaminants in the form of a non-aqueous phase liquid (NAPL). In permeable soils, SVE is characterized as a relatively quick and effective in-situ remediation technique. It is expected to be effective in the soils present at the Gehl site Electrical Resistance Heating Electrical resistance heating is an in-situ electrical heating technology that applies electricity into the ground through electrodes. The electrodes can be installed either vertically to about 100 feet or horizontally as site conditions warrant. Electrical resistance heating enhances the recovery of soils contaminated with volatile and semivolatile organic compounds (VOCs and SVOCs). Electrical resistance heating assists SVE by heating the contaminants in the soil. It raises the vapor pressure of VOCs and SVOCs, increasing volatilization and removal. As electrical resistance heating dries the soil, it also creates a source of steam that strips contaminants from soils.

27 SECTION 5 Three-phase heating and six-phase heating (SPH) are varieties of electrical resistance heating. SPH splits conventional three-phase electricity into six separate electrical phases, with each phase delivered to a single electrode. The six electrodes are placed in a hexagonal pattern, with the vapor extraction well located in the center of the hexagon. SPH is very good for circular areas less than 65 feet in diameter. In larger areas, there may be flaws that cause uneven heating. Three-phase is ideal for larger areas and irregular areas. 5.4 Comparative Analysis Summary Soil A comparison of each of these remedial approaches was performed in order to screen the technologies relative to their applicability to the Gehl site. The remedial approaches were rated against selected criteria to evaluate their ability relative to 1) meet the RAOs; 2) the desired time frame for achieving cleanup goals; 3) their implementability from a) a regulatory, b) logistical and c) technical perspective; and 4) their relative cost. The comparative analysis assigned a numerical value to each qualifier used for describing compatibility with, or ability to meet each of the criteria. The numerical values were then summed in order to develop a score for the alternatives. The three highest scoring alternatives were retained for detailed evaluation along with the No Action alternative. Table 5 provides a summary of this comparative evaluation. Based on this evaluation, the following alternatives were retained for further analysis: S-1 No Action S-2 In-Place Capping S-3 Excavation and Off-Site Disposal S-4 Soil Vapor Extraction The following section provides a detailed discussion of these approaches along with considerations for implementation at the Gehl site. This detailed discussion presumes that the West Plant concrete floor will remain in place for several years. If this concrete floor is removed, or if redevelopment of the West Plant occurs such that human occupancy of the space above the West Plant concrete floor takes place, the required remedial activity will need to be reevaluated. At the Gehl site, five contaminated soil areas were identified in Table 3 for detailed analyses. The two identified areas with PVOC contamination share similar characteristics and close proximity: 1) Maintenance Garage South and 2) MW-4 Area. These two areas will be evaluated in one detailed analyses. Three areas were selected in Table 3 for detailed analyses with CVOC contamination: 1) West Plant North, 2) West Plant Southeast Loading Docks and 3) Maintenance Garage East. Each of these areas will be evaluated in a detailed analysis. 5.5 Groundwater Technology Screening The following subsections provide a brief discussion of the no action alternative and selected technologies that were considered as potentially viable technologies for mitigating the detected 19

28 20 SECTION 5 COCs and to meet the RAOs. Each of the technologies are discussed in general terms, and then evaluated against selected criteria to determine which technologies would be retained for further detailed analysis. The selected technologies are: 1. No Action 2. Monitored Natural Attenuation 3. Groundwater Pump and Treat 4. In Situ Biological Treatment 5. In Situ Chemical Oxidation No Action This alternative assumes that no action will be taken and the existing site conditions will remain as they currently exist. This is selected as the first alternative to be used as a baseline for comparison of the relative improvement that will be afforded by other alternatives. This alternative requires that an institutional control (WDNR GIS registration) be implemented for the affected portion of the property. The WDNR may restrict groundwater use and will require future disruptive site activities to properly handle any contaminated groundwater encountered. The use of WDNR GIS registration in conjunction with a WDNR-approved Groundwater Monitoring Plan may be appropriate for portions of the site where natural attenuation will remediate groundwater on site Monitored Natural Attenuation This alternative presumes that naturally occurring degradation processes will remediate the contaminant levels in groundwater in a reasonable period of time. The WDNR may restrict groundwater use and will require future disruptive site activities to properly handle any contaminated groundwater encountered. The use of WDNR GIS registration in conjunction with a WDNR-approved Groundwater Monitoring Plan will be required for all portions of the site where natural attenuation is selected to remediate groundwater Groundwater Pump and Treat This alternative will use a network of groundwater recovery wells located within the site and/or along the site boundaries to capture contaminated groundwater and pipe it to a designed treatment system consisting of sediment filtration and an air stripper to remove CVOCs. Treated groundwater will be discharged to a storm sewer under a WPDES permit In-Situ Bioremediation In-situ bioremediation options include enhanced bioremediation or bioaugmentation. Bioremediation is a process in which indigenous or inoculated microorganisms (i.e., fungi, bacteria, and other microbes) transform organic materials in groundwater. Enhanced bioremediation is a process that attempts to accelerate the natural biodegradation process by providing nutrients and electron donors (such as lactate, molasses or vegetable oil) whose absence or limited availability may otherwise be limiting the rate of conversion of organics to

29 SECTION 5 non-toxic end products. Bioaugmentation goes a step further and adds microorganisms that will degrade site contaminants to augment the indigenous bacteria. This alternative will use a network of installed injection points to blanket the target contaminated groundwater area with electron donor and bioaugmentation culture. The target contaminated groundwater area would include source areas and/or areas of higher VOC concentrations In Situ Chemical Oxidation Chemical oxidation involves the injection into the subsurface of chemicals which have a high oxidizing potential to degrade the organic contamination to carbon dioxide and water. The technology has been used to treat chlorinated solvent constituents. The technology is typically applied for the treatment of a source area, and has only been applied to large-scale sites on a limited basis. Chemical oxidants include hydrogen peroxide, Fenton s reagent and permanganate. These oxidants are injected in a tight grid pattern throughout the area requiring treatment. More than one application of chemical oxidant may be required due to rebound effects as residual contaminants desorb from the soil. 5.6 Comparative Analyses Summary Groundwater A comparison of each of these remedial approaches was performed in order to screen the technologies relative to their applicability to the Gehl site. The remedial approaches were rated against selected criteria to evaluate their ability relative to 1) meet the RAOs; 2) the desired time frame for achieving cleanup goals; 3) their implementability from a) a regulatory, b) logistical and c) technical perspective; and 4) their relative cost. The comparative analysis assigned a numerical value to each qualifier used for describing compatibility with, or ability to meet each of the criteria. The numerical values were then summed in order to develop a score for the alternatives. The three highest scoring alternatives were retained for detailed evaluation along with the No Action alternative. Table 6 provides a summary of this comparative evaluation. Based on this evaluation, the following alternatives were developed and retained for further analysis: GW-1 No Action GW-2 Groundwater Pump and Treat with MNA GW-3 Groundwater Pump and Treat GW-4 In-Situ Bioremediation with MNA The following section provides a detailed discussion of these alternatives along with considerations for implementation at the Gehl site. This detailed discussion presumes that the West Plant concrete floor will remain in place for several years. If this concrete floor is removed, or if redevelopment of the West Plant occurs such that human occupancy of the space above the West Plant concrete floor takes place, the required remedial activity will need to be reevaluated. 21

30 SECTION 5 At the Gehl site, three contaminated groundwater areas were identified in Table 4 for detailed analyses. These three identified areas with CVOC contamination share similar characteristics and when examined with the four groundwater remediation alternatives listed allow evaluation as one unit. This approach coincides with the findings of the site investigation and the CVOC contaminant mapping. 22

31 SECTION DETAILED ANALYSIS OF ALTERNATIVES This section provides a detailed analysis of the soil and groundwater remediation alternatives. Detailed cost estimates for each are alternative are provided in Appendix C and summarized on Table 7. The net present value (NPV) estimate is calculated using an interest rate of 4%. 6.1 Detailed Analysis of Soil Alternatives Maintenance Garage South & MW-4 Area Left undisturbed, the PVOC contaminated soils in this area are not an inhalation or ingestion hazard. The PVOC levels present are above those protective of groundwater, but PVOC groundwater contamination has not left the site and is expected to decrease with time. The total impacted surface area is estimated at 9,500 square feet. With groundwater at 10 feet below surface grade, this indicates 3,500 cubic yards or 5,300 tons of petroleum contaminated soil is present above the water table. There is no concrete cover over these soils. The gravel surface and nearby Forest Avenue provide ready access to the PVOC contaminated soil areas Alternative S-1: No Action Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the Maintenance Garage South & MW-4 Area. Because contaminated media would remain inplace, the potential for continued migration of contaminants would not be mitigated. No institutional controls would be implemented to prevent intrusive activities into the waste materials. As discussed above, the No Action alternative has been included to provide a basis for comparison with the remaining alternatives. The No Action Alternative provides no protection of human health or the environment, and cleanup levels would not be met. This alternative does not improve on the minimal protection already provided by the existing cover soils, nor is it considered a permanent remedy because it does not reduce the toxicity, volume, or mobility of the COCs on the Site. Therefore, the capability to achieve the RAOs for this Site within a reasonable timeframe is not present. The No Action alternative is readily implementable in that nothing is required to be constructed, maintained, or monitored aside from the natural attenuation groundwater monitoring. However, the implementability of this alternative from a regulatory perspective is virtually non-existent in that the no-action alternative will not satisfy the regulatory objectives for the Site. There are limited to no additional costs associated with this alternative Alternative S-2: In-Place Capping Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the Maintenance Garage South & MW-4 Area. The contaminated soils would remain in place and a cap of additional soil would be placed to cover the contaminated soil areas. The cap could also consist of concrete or asphalt. The cap would slow the vertical migration of petroleum 23

32 24 SECTION 6 contaminants and remove the contact hazard for intrusive activities. The intrusive activity hazard could also be eliminated by institutional controls, including fencing, signage, and public records restricting intrusive activities at the site without an approved plan to handle and dispose of petroleum contaminated soil. This alternative can adequately satisfy the need to protect human health and the environment. This alternative improves upon the minimal protection already provided by the existing cover soils, and may become a permanent remedy as natural biodegradation reduces the toxicity, volume, and mobility of the COCs on the Site. The capability of this alternative to achieve the RAOs for the site will require a long timeframe. This long timeframe may fit the City s final use for the site. The In-Place Capping alternative is readily implementable. An institutional control not permitting any site disturbance in the Maintenance Garage South & MW-4 Area will be adequate. Should the City of West Bend decide to allow any site disturbance, a plan to properly handle and dispose of petroleum contaminated soils would be required. The implementability of this alternative from a regulatory perspective should be permissible with the use of the WDNR GIS registry and a WDNR-approved Operation and Maintenance Plan in place. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $46,151, operation and maintenance (O&M) costs of $3,452 and a total NPV of $49, Alternative S-3: Excavation and Off-Site Disposal Under this alternative, contaminated soils in the Maintenance Garage South & MW-4 Area would be excavated, loaded into licensed special waste hauler trucks, and transported for disposal at a Wisconsin-certified landfill facility. Clean fill would be used to back fill the excavation to the extent necessary for continued site use. This alternative eliminates the vertical migration and intrusive activity hazards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Excavation and Off-Site Disposal alternative is implementable. Due to the urban setting, precautions for dust control and trucking will be required. This alternative is routine in administration and is technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $339,749 and no O&M costs for a total NPV of $339, Alternative S-4: Soil Vapor Extraction Under this alternative, contaminated soils in the Maintenance Garage South & MW-4 Area would be treated with a grid of installed SVE wells and manifold piping network connected to a vacuum blower. The blower would extract soil vapor from the contaminated areas and exhaust

33 25 SECTION 6 to the atmosphere without treatment as the discharge would be below emission standards. This alternative eliminates the vertical migration and intrusive activity hazards. The soils in this area are suitably permeable for this alternative. The SVE system is assumed to operate for three years before meeting cleanup standards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Soil Vapor Excavation alternative is implementable. Due to the lack of concrete, asphalt, or any impermeable cover, a temporary impermeable surface will be necessary for this alternative to be effective. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $268,793, O&M costs of $98,400 and a total NPV of $367, West Plant North The CVOC contaminated soils in this area are an ingestion hazard, an inhalation hazard, and have CVOC levels above those protective of groundwater. The CVOC contaminated soils may be contributing to groundwater contamination in the smear zone. The total impacted surface area is estimated at 57,000 square feet. Soil sample results indicate soils requiring remediation are limited to an average 5-foot depth. This indicates 10,500 cubic yards or 15,750 tons of COVC contaminated soil are present. These soils are completely covered by the West Plant concrete floor. Access to the soils is adequate via Forest Avenue but difficult with the West Plant building in place Alternative S-1: No Action Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the West Plant North Area. Because contaminated media would remain in-place, the potential for continued migration of contaminants would not be mitigated. No institutional controls would be implemented to prevent intrusive activities into the waste materials. As discussed above, the No Action alternative has been included to provide a basis for comparison with the remaining alternatives. The No Action Alternative provides no protection of human health or the environment, and cleanup levels would not be met. This alternative does not improve on the minimal protection already provided by the existing cover soils, nor is it considered a permanent remedy because it does not reduce the toxicity, volume, or mobility of the COCs on the Site. Therefore, the capability to achieve the RAOs for this Site within a reasonable timeframe is not present. The No Action alternative is readily implementable in that nothing is required to be constructed, maintained, or monitored aside from the natural attenuation groundwater monitoring. However,

34 26 SECTION 6 the implementability of this alternative from a regulatory perspective is virtually non-existent in that the no-action alternative will not satisfy the regulatory objectives for the Site. There are limited to no additional costs associated with this alternative Alternative S-2: In-Place Capping Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the West Plant North Area. The contaminated soils would remain in place and the in-place concrete floor slab and building system would continue to cover the contaminated soil area. The cap would slow the vertical migration of CVOC contaminants and remove the direct contact hazard. Any intrusive activity hazard could also be additionally mitigated by institutional controls, including fencing, signage, and public records restricting intrusive activities at the site without an approved plan to handle and dispose of disturbed CVOC contaminated soil. This alternative can adequately satisfy the need to protect human health and the environment. This alternative uses the protection already provided by the existing floor slab and building, and may become part of permanent remedy as long as the concrete floor slab remains in place. The capability of this alternative to achieve the RAOs for the site will require a long timeframe. This long timeframe may fit the City s final use for the site. The In-Place Capping alternative is readily implementable. An institutional control not permitting any site disturbance in the West Plant North Area will be adequate. Should the City of West Bend decide to allow any site disturbance, a plan to properly handle and dispose of CVOC contaminated soils would be required. The implementability of this alternative from a regulatory perspective should be permissible with the use of the WDNR GIS registry and a WDNR-approved Operation and Maintenance Plan in place. For this alternative, management of the vapor intrusion pathway would be required as part of the Operation and Maintenance Plan. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $16,625, O&M costs of $3,458 and a total NPV of $20, Alternative S-3: Excavation and Off-Site Disposal Under this alternative, contaminated soils in the West Plant North Area would be excavated, loaded into licensed special waste hauler trucks, and transported for disposal at a Wisconsincertified landfill facility. Clean fill would be used to back fill the excavation to the extent necessary for continued site use. This alternative eliminates the vertical migration and intrusive activity hazards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Excavation and Off-Site Disposal alternative is implementable, but would be very difficult with the building in place. Due to the urban setting, precautions for dust control and trucking

35 27 SECTION 6 will be required. To adequately access the soils, building demolition and floor slab removal would be necessary. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $1,059,013 and no O&M costs for a total NPV of $1,059, Alternative S-4: Soil Vapor Extraction Under this alternative, contaminated soils in the West Plant North Area would be treated with a grid of installed soil vapor extraction wells and manifold piping network connected to a vacuum blower. The blower would extract soil vapor from the contaminated areas and exhaust to the atmosphere without treatment as the discharge would be below emission standards. This alternative eliminates the vertical migration and intrusive activity hazards. The soils in this area are suitably permeable for this alternative. The SVE system is assumed to operate for three years before meeting cleanup standards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Soil Vapor Excavation alternative is implementable. The existing concrete floor slab will aid in the extraction efficiency. This alternative is routine in administration and technically feasible. In addition, the soil vapor extraction well network could serve as a long term vapor intrusion remedy if the current building is reused or a new structure is built on the existing floor slab. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $671,650, O&M costs of $148,800 and a total NPV of $820, West Plant Southeast Loading Docks The CVOC contaminated soils in this area are not an ingestion hazard, but are an inhalation hazard, and have CVOC levels above those protective of groundwater. The CVOC contaminated soils may be contributing to groundwater contamination in the smear zone. The total impacted surface area is estimated at 1,300 square feet. Soil sample results indicate soils requiring remediation are limited to an average 5-foot depth. This indicates 240 cubic yards or 360 tons of COVC contaminated soil are present. These soils are completely covered by the loading dock and Forest Avenue pavements. Access to the soils is adequate via Forest Avenue Alternative S-1: No Action Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the West Plant Southeast Loading Docks. Because contaminated media would remain inplace, the potential for continued migration of contaminants would not be mitigated. No institutional controls would be implemented to prevent intrusive activities into the waste materials. As discussed above, the No Action alternative has been included to provide a basis for comparison with the remaining alternatives.

36 28 SECTION 6 The No Action Alternative provides no protection of human health or the environment, and cleanup levels would not be met. This alternative does not improve on the minimal protection already provided by the existing cover soils, nor is it considered a permanent remedy because it does not reduce the toxicity, volume, or mobility of the COCs on the Site. Therefore, the capability to achieve the RAOs for this Site within a reasonable timeframe is not present. The No Action alternative is readily implementable in that nothing is required to be constructed, maintained, or monitored aside from the natural attenuation groundwater monitoring. However, the implementability of this alternative from a regulatory perspective is virtually non-existent in that the no-action alternative will not satisfy the regulatory objectives for the Site. There are limited to no additional costs associated with this alternative Alternative S-2: In-Place Capping Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the West Plant Southeast Loading Docks Area. The contaminated soils would remain in place and the in-place concrete loading dock slab and Forest Avenue pavement would continue to cover the contaminated soil area. The cap would slow the vertical migration of CVOC contaminants and remove the contact hazard. The intrusive activity hazard could also be additionally mitigated by institutional controls, including signage and public records restricting intrusive activities at the site without an approved plan to handle and dispose of disturbed CVOC contaminated soil. This alternative can adequately satisfy the need to protect human health and the environment. This alternative uses the protection already provided by the existing concrete and asphalt surfaces, and may become part of permanent remedy as long as the concrete and asphalt remain in place. The capability of this alternative to achieve the RAOs for the site will require a long timeframe. This long timeframe may fit the City s final use for the site. The In-Place Capping alternative is readily implementable. An institutional control not permitting any site disturbance in the West Plant Southeast Loading Dock Area will be adequate. Should the City of West Bend decide to allow any site disturbance, a plan to properly handle and dispose of CVOC contaminated soils would be required. The implementability of this alternative from a regulatory perspective should be permissible with the use of the WDNR GIS registry and a WDNR-approved Operation and Maintenance Plan in place. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $16,625, O&M costs of $3,458 and a total NPV of $20, Alternative S-3: Excavation and Off-Site Disposal Under this alternative, contaminated soils in the West Plant Southeast Loading Docks Area would be excavated, loaded into licensed special waste hauler trucks, and transported for disposal at a Wisconsin-certified landfill facility. Clean fill would be used to back fill the

37 SECTION 6 excavation to the extent necessary for continued site use. This alternative eliminates the vertical migration and intrusive activity hazards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Excavation and Off-Site Disposal alternative is easily implementable. Due to the urban setting, precautions for dust control and trucking will be required. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $35,218 and no O&M costs for a total NPV of $35, Alternative S-4: Soil Vapor Extraction Under this alternative, contaminated soils in the West Plant Southeast Dock Area would be treated with a grid of installed soil vapor extraction wells and manifold piping network connected to a vacuum blower. The blower would extract soil vapor from the contaminated areas and exhaust to the atmosphere without treatment as the discharge would be below emission standards. This alternative eliminates the vertical migration and intrusive activity hazards. The soils in this area are suitably permeable for this alternative. The SVE system is assumed to operate for three years before meeting cleanup standards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Soil Vapor Excavation alternative is implementable. The existing concrete and asphalt surfaces will aid in the extraction efficiency. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $153,748, O&M costs of $55,200 and a total NPV of $208, Maintenance Garage East The CVOC contaminated soils in this area are an ingestion hazard, an inhalation hazard, and have CVOC levels above those protective of groundwater. The CVOC contaminated soils may be contributing to groundwater contamination in the smear zone. The total impacted surface area is estimated at 18,000 square feet. Soil sample results indicate soils requiring remediation are limited to an average 5-foot depth. This indicates 3,300 cubic yards or 5,000 tons of COVC contaminated soil are present. These soils are completely covered by concrete and Forest Avenue pavements. Access to the soils is adequate via Forest Avenue. 29

38 30 SECTION Alternative S-1: No Action Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the Maintenance Garage East Area. Because contaminated media would remain in-place, the potential for continued migration of contaminants would not be mitigated. No institutional controls would be implemented to prevent intrusive activities into the waste materials. As discussed above, the No Action alternative has been included to provide a basis for comparison with the remaining alternatives. The No Action Alternative provides no protection of human health or the environment, and cleanup levels would not be met. This alternative does not improve on the minimal protection already provided by the existing cover soils, nor is it considered a permanent remedy because it does not reduce the toxicity, volume, or mobility of the COCs on the Site. Therefore, the capability to achieve the RAOs for this Site within a reasonable timeframe is not present. The No Action alternative is readily implementable in that nothing is required to be constructed, maintained, or monitored aside from the natural attenuation groundwater monitoring. However, the implementability of this alternative from a regulatory perspective is virtually non-existent in that the no-action alternative will not satisfy the regulatory objectives for the Site. There are limited to no additional costs associated with this alternative Alternative S-2: In-Place Capping Under this alternative, no action would be taken to remove, treat, or contain contaminated soils in the Maintenance Garage East Area. The contaminated soils would remain in place and the inplace concrete slab and Forest Avenue pavement would continue to cover the contaminated soil area. The cap would slow the vertical migration of CVOC contaminants and remove the contact hazard. The intrusive activity hazard could also be additionally mitigated by institutional controls, including signage and public records restricting intrusive activities at the site without an approved plan to handle and dispose of disturbed CVOC contaminated soil. This alternative can adequately satisfy the need to protect human health and the environment. This alternative uses the protection already provided by the existing concrete and asphalt surfaces, and may become part of permanent remedy as long as the concrete and asphalt remain in place. The capability of this alternative to achieve the RAOs for the site will require a long timeframe. This long timeframe may fit the City s final use for the site. The In-Place Capping alternative is readily implementable. An institutional control not permitting any site disturbance in the Maintenance Garage East Area will be adequate. Should the City of West Bend decide to allow any site disturbance, a plan to properly handle and dispose of CVOC contaminated soils would be required. The implementability of this alternative from a regulatory perspective should be permissible with the use of the WDNR GIS registry and a WDNR-approved Operation and Maintenance Plan in place. A cost estimate for this alternative

39 31 SECTION 6 is included in Appendix C indicating a capital cost of $16,625, O&M costs of $3,458 and a total NPV of $20, Alternative S-3: Excavation and Off-Site Disposal Under this alternative, contaminated soils in the Maintenance Garage East Area would be excavated, loaded into licensed special waste hauler trucks, and transported for disposal at a Wisconsin-certified landfill facility. Clean fill would be used to back fill the excavation to the extent necessary for continued site use. This alternative eliminates the vertical migration and intrusive activity hazards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Excavation and Off-Site Disposal alternative is easily implementable. Due to the urban setting, precautions for dust control and trucking will be required. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $378,851 and no O&M costs for a total NPV of $378, Alternative S-4: Soil Vapor Extraction Under this alternative, contaminated soils in the Maintenance Garage East Area would be treated with a grid of installed soil vapor extraction wells and manifold piping network connected to a vacuum blower. The blower would extract soil vapor from the contaminated areas and exhaust to the atmosphere without treatment as the discharge would be below emission standards. This alternative eliminates the vertical migration and intrusive activity hazards. The soils in this area are suitably permeable for this alternative. The SVE system is assumed to operate for three years before meeting cleanup standards. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. The Soil Vapor Excavation alternative is implementable. The existing concrete and asphalt surfaces will aid in the extraction efficiency. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $302,575, O&M costs of $73,200 and a total NPV of $375, Detailed Analysis of Groundwater Alternatives The single combined groundwater contaminant area for detailed analyses as described in section 5.6 includes:

40 SECTION 6 MW-6 West Plant Southeast Loading Docks West Plant - North West Plant - South (Sump) Alternative GW-1: No Action Under this alternative, no action would be taken to remove, treat, or contain contaminated groundwater. The potential for continued migration of contaminants would not be mitigated. No institutional controls would be implemented to prevent intrusive activities. As discussed above, the No Action alternative has been included to provide a basis for comparison with the remaining alternatives. The No Action Alternative provides no protection of human health or the environment, and cleanup levels would not be met. This alternative does not improve on the minimal protection already provided by the existing cover soils, nor is it considered a permanent remedy because it does not reduce the toxicity, volume, or mobility of the COCs on the Site. Therefore, the capability to achieve the RAOs for this Site within a reasonable timeframe is not present. The No Action alternative is readily implementable in that nothing is required to be constructed, maintained, or monitored aside from the natural attenuation groundwater monitoring. However, the implementability of this alternative from a regulatory perspective is virtually non-existent in that the no-action alternative will not satisfy the regulatory objectives for the Site. There are limited to no additional costs associated with this alternative Alternative GW-2: Groundwater Pump and Treat with MNA Under this alternative, a sufficient number of groundwater extraction wells are installed to adequately capture the most contaminated portions of the on-site groundwater plume while allowing monitored natural attenuation (MNA) to address the low level contaminants outside the capture zone. This alternative seeks to rapidly remediate the on-site groundwater to eliminate the contaminated groundwater moving off site as a continuing groundwater exposure pathway and vapor intrusion pathway. Treatment of groundwater on-site will include air stripping to meet permit standards listed in a WPDES permit for subsequent disposal of treated groundwater into the storm sewer (Milwaukee River within several hundred feet). A preliminary capture zone analyses suggests that two extraction wells placed in a north-south line, the southern groundwater extraction well located at the MW-6 location and the northern groundwater extraction well located at the MW-32 Area will be sufficient to reach the entire site east to west at a total pumping rate of 75 GPM (Figure 14). Included with this alternative is a quarterly groundwater monitoring program to assess performance and evaluate MNA. 32

41 33 SECTION 6 This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. Alternative GW-2 is implementable. This alternative will cause minimal site disruption and can be modified to become permanent and hidden below and with new construction if necessary. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $202,439, O&M costs of $1,400,393 and a total NPV of $1,602, Alternative GW-3: Groundwater Pump and Treat Under this alternative, a sufficient number of groundwater extraction wells are installed to completely capture the most contaminated portions of the on-site groundwater plume plus recover as much groundwater moving off-site as possible. This alternative seeks to rapidly remediate the on-site groundwater to eliminate the contaminated groundwater moving off site as a continuing groundwater exposure pathway and vapor intrusion pathway and recover and treat s much groundwater contamination near the site boundaries as possible. Treatment of groundwater on-site will include air stripping to meet permit standards listed in a WPDES permit for subsequent disposal of treated groundwater into the storm sewer (Milwaukee River within several hundred feet). A preliminary capture zone analyses suggests that two extraction wells placed in a north-south line, the southern groundwater extraction well one located at the MW-6 location and the northern groundwater extraction well located at the MW-32 Area plus five additional groundwater extraction wells placed along the site boundaries, will be sufficient to reach the maximum amount of potentially contaminated groundwater, at an estimated total pumping rate of 275 GPM (Figure 15). This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. Alternative GW-3 is implementable. This alternative will cause minimal site disruption and can be modified to become permanent and hidden below and with new construction if necessary. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $607,092, O&M costs of $2,312,632 and a total NPV of $2,919, Alternative GW-4: Bioremediation with MNA Under this alternative injection wells will be installed in the four areas shown on Figure 16 that contain TCE and/or vinyl chloride at concentrations ten times above the enforcement standard.

42 SECTION 6 Injection wells would be installed on a 50-foot offset grid pattern over the hotspot areas resulting in approximately 80 injection wells. The injection wells would be constructed of 1-inch diameter PVC pipe to a depth of 15 to 30 feet and screened across the lower 10 feet (upper 10 feet of saturated zone) and completed with flush mount vaults. The estimated electron donor demand for each well would be 1350 pounds (175 gallons) blended with 35,000 gallons of water (approximately 0.5% solution) for an effective radius of influence of 25 feet. Make up water could be supplied by municipal water or extracted groundwater. A second injection at 60% of the wells is assumed 2 to 3 years after the first for maintenance of the bioremediation zone. This alternative includes monitoring groundwater quality and collecting physical parameter data to assess the progression and effectiveness of MNA. This alternative can adequately satisfy the need to protect human health and the environment. This alternative provides a permanent remedy and will achieve the RAOs for the site in a rapid timeframe. Alternative GW-4 is implementable but would require off-site access at some locations. Actual locations would need to be determined during the remedial design phase. This alternative is routine in administration and technically feasible. A cost estimate for this alternative is included in Appendix C indicating a capital cost of $555,345, O&M costs of $691,680 and a total NPV of $1,247,

43 SECTION CONCLUSIONS This identification and evaluation of remedial action options (RAO) was prepared for the City of West Bend in compliance with NR 722 of the Wisconsin Administrative Code for the Former Gehl Company Properties site. 7.1 Selected Soil Remedial Alternative The analyses reviewed eight potential alternatives, and then performed a detailed evaluation of four selected alternatives. Due to the shallow nature of the contamination, excavation methods would normally be preferred over in situ treatment techniques. The use of existing concrete surfaces that will remain in place makes the use of capping alternatives practical. Besides cost and future site use, the other driving factor in remedy selection is the proximity of the residential area to the east of the West Plant as a receptor for the vapor intrusion pathway. The desirability of removing contaminants in a source area and thereby reducing the potential for leaching to groundwater will aid in reducing the vapor migration/vapor intrusion potential Maintenance Garage South & MW-4 Area Based upon the criteria discussed in the detailed evaluation, Alternative S-2 (In-Place Capping) is the recommended alternative for mitigating COCs in the Maintenance Garage South & MW-4 area. The No Action alternative will not achieve RAOs for the Site and is therefore removed from consideration. Alternatives S-3 (Excavation and Off-Site Disposal) and S-4 (Soil Vapor Extraction) are significantly higher in cost, without providing any additional protection to any current receptors. The petroleum compounds present in groundwater are not migrating off site, and a capping strategy will provide adequate protection of human health and the environment. Petroleum as a vapor intrusion hazard is not a consideration as no receptors are present between this area and the Milwaukee River. Shallow groundwater flow is unlikely to cause vapor migration to the east (towards the residential area) in the future. Alternative S-2 meets the current City land use plan for this area. It is likely that a portion or all of this area will become a green space along the river. The final grades will include a plan to furnish a four-foot thick layer of clean soil to provide sufficient protection for the direct contact hazard. In the short term, until the final land use is determined, fencing, signage, and City records and notices prohibiting intrusive site activities in this area will be used to provide protection of human health and the environment. Should the final land use for this area change, and intrusive activities become necessary for redevelopment, petroleum-contaminated soils will be remediated using one of the remedies listed in this report. This requirement will be included in the Operation and Maintenance Plan included as an Institutional Control for this area. 35

44 36 SECTION 7 The estimated time frame for implementation of the selected alternative is one year. This time frame will allow compliance with all applicable federal and state environmental laws and standards. Performance of the selected remedial option will be measured by the site-wide groundwater monitoring program. No treatment residuals are generated by the recommended remedial alternative West Plant North Based upon the criteria discussed in the detailed evaluation, Alternative S-2 (In-Place Capping) is the recommended alternative for mitigating COCs in the West Plan North area. The No Action alternative will not achieve RAOs for the Site and is therefore removed from consideration. Alternatives S-3 (Excavation and Off-Site Disposal) and S-4 (Soil Vapor Extraction) are significantly higher in cost, without providing any additional protection to any current receptors. The CVOC compounds present are primarily located in shallow soils immediately below the concrete floor slab, which completely covers the area. The current concrete cap provides adequate protection of human health and the environment. Alternative S-2 meets the current City plan for this area. It is likely that the existing West Plant building will be demolished, with the floor slab remaining until a redevelopment plan is finished, likely driven by the demand for this portion of the site by a property buyer/redevelopment. In the short term, until the final land use is determined, fencing, signage, and City records and notices prohibiting intrusive site activities in this area will additionally be used to provide protection of human health and the environment. Should the final land use for this area change, and intrusive activities are necessary for redevelopment, CVOC-contaminated soils will be remediated using one of the remedies listed in this report. This requirement will be included in the Operation and Maintenance Plan included as an Institutional Control for this area. It is possible that a more aggressive soil remedy will be desired at this area if it becomes apparent that a reduction in contaminant mass in the West Plant-North soils will aid in abating the COVC vapor intrusion hazard that may exist in the residential area east of the West Plant. If this need arises Alternatives S-3 or S-4 could be implemented. The estimated time frame for implementation of the selected alternative is one year. This time frame will allow compliance with all applicable federal and state environmental laws and standards. Performance of the selected remedial option will be measured by the site-wide groundwater monitoring program. No treatment residuals are generated by the recommended remedial alternative West Plant Southeast Loading Docks Based upon the criteria discussed in the detailed evaluation, Alternative S-2 (In-Place Capping) is the recommended alternative for mitigating COCs in the West Plant Southeast Loading Dock

45 37 SECTION 7 area. The No Action alternative will not achieve RAOs for the Site and is therefore removed from consideration. Alternative S-3 (Excavation and Off-Site Disposal) is similar in cost, but a calculation of the contaminant mass in the 360 tons to be excavated indicates approximately 120 grams (0.25 pounds) of COVCs would be removed. Alternative S-4 (Soil Vapor Extraction) is significantly higher in cost, without providing any additional protection to any current receptors. The CVOC compounds present are primarily located in shallow soils immediately below surface pavements, which completely cover the area. The current concrete and asphalt cap provides adequate protection of human health and the environment. CVOC compounds have been found in vapor sampling to the east in Forest Avenue (sample SG-102, Figure 13) adjacent to the east residential area, which may cause the selected alternative of In-Place Capping to be reconsidered in the future. Alternative S-2 meets the current City plan for this area. It is likely that the existing pavements will be preserved until a redevelopment plan is finished, likely driven by the demand for this portion of the site by a buyer. In the short term, until the final land use is determined, fencing, signage, and City records and notices prohibiting intrusive site activities in this area will additionally be used to provide protection of human health and the environment. Should the final land use for this area change, and intrusive activities are necessary for redevelopment, CVOC-contaminated soils will be remediated using one of the remedies listed in this report. This requirement will be included in the Operation and Maintenance Plan included as an Institutional Control for this area. It is possible that a more aggressive soil remedy will be desired at this area if it becomes apparent that a reduction in contaminant mass in the West Plant Southeast Loading Dock soils will aid in abating the COVC vapor intrusion hazard that may exist in the residential area east of the West Plant. If this need arises Alternatives S-3 or S-4 could be implemented. The estimated time frame for implementation of the selected alternative is one year. This time frame will allow compliance with all applicable federal and state environmental laws and standards. Performance of the selected remedial option will be measured by the site-wide groundwater monitoring program. No treatment residuals are generated by the recommended remedial alternative Maintenance Garage East Based upon the criteria discussed in the detailed evaluation, Alternative S-2 (In-Place Capping) is the recommended alternative for mitigating COCs in the Maintenance Garage East area. The No Action alternative will not achieve RAOs for the Site and is therefore removed from consideration. Alternative S-3 (Excavation and Off-Site Disposal) and Alternative S-4 (Soil Vapor Extraction) are significantly higher in cost, without providing any additional protection to any current receptors. A rough calculation of the contaminant mass in the 5,000 tons to be remediated indicates approximately three pounds of COVCs would be removed. The CVOC

46 38 SECTION 7 compounds present are primarily located in shallow soils immediately below surface pavements and the garage floor, which completely cover the area. The current concrete and asphalt cap provides adequate protection of human health and the environment. CVOC compounds were not found in vapor sampling to the east in Forest Avenue (sample SG-101) adjacent to the east residential area, which suggests that the Maintenance Garage East soils are not a source for contamination via the vapor intrusion pathway. Alternative S-2 meets the current City plan for this area. It is likely that the existing pavements and floor slab will be preserved until a redevelopment plan is finished, likely driven by the demand for this portion of the site by a buyer. In the short term, until the final land use is determined, fencing, signage, and City records and notices prohibiting intrusive site activities in this area will additionally be used to provide protection of human health and the environment. Should the final land use for this area change, and intrusive activities are necessary for redevelopment, CVOC-contaminated soils will be remediated using one of the remedies listed in this report. This requirement will be included in the Operation and Maintenance Plan included as an Institutional Control for this area. It is possible that a more aggressive soil remedy will be desired at this area if it becomes apparent that a reduction in contaminant mass in the Maintenance Garage East area will aid in abetting the COVC vapor intrusion hazard that may exist in the residential area east of the West Plant. If this need arises Alternatives S-3 or S-4 could be implemented. The estimated time frame for implementation of the selected alternative is one year. This time frame will allow compliance with all applicable federal and state environmental laws and standards. Performance of the selected remedial option will be measured by the site-wide groundwater monitoring program. No treatment residuals are generated by the recommended remedial alternative. 7.2 Selected Groundwater Remedial Alternative The analyses reviewed seven potential technologies, and then performed a detailed evaluation of four selected alternatives. The recommended groundwater remedial action option is Alternative GW-4 (Bioremediation with MNA). Alternative GW-4 is the lowest cost alternative and directly addresses the four areas with the highest CVOC concentrations, including the two areas adjacent to the Milwaukee River. It is expected that the hotspot areas would be remediated with bioremediation within two to four years (one or two injections) and MNA would be used for the remaining site-wide low level CVOCs. Remediation could begin with a small scale pilot test in one of the areas to optimize injection parameters and demonstrate performance before going fullscale. Alternative GW-4 meets the current City plan for this site. The injection wells can be located and designed to accommodate current site conditions and could likely be abandoned prior to

47 SECTION 7 future redevelopment. After injection well abandonment, the long term O&M would be limited to groundwater monitoring. The cost estimates conservatively assumed quarterly monitoring for 30 years, however it is expected that both the frequency and scope of monitoring would be reduced over time. Alternative GW-2 (Groundwater Pump and Treat with MNA) is the preferred pump and treat option compared to GW-3 which is twice the cost without providing any additional protection to any current receptors. Although Alternative GW-2 does not directly address the hotpsots near the Milwaukee River (like GW-3 and GW-4), a previous submittal has shown that the calculated flux of contaminants discharging to the river is less than four pounds per year resulting in concentrations far below any surface water quality standards. While GW-2 has lower capital costs than GW-4, the long term O&M costs of the treatment system make it more expensive than GW-4. 39

48 FIGURES

49

50 West Parking Lot East Parking Lot Gehl Co. Engineering and Research Building Gehl Co. Manufacturing and Office Building Former Maintenance Garage Legend Parcel Boundary 431 TITLE: 2005 Aerial Photo of TIF District # Property address inch = 120 feet LOCATION: 150 Feet West Bend, Wisconsin CHECKED M.R.N. Map features maintained and provided by the City of West Bend. DRAFTED FILE DATE M.A.M. Aerial-2005_Fig /04/2011 FIGURE: 2

51 Designation A B C D E F G H I J K L M N O P Q R S T U V Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST

52 Designation A B C D E F G H I J K L M N O P Q R S T U V Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST

53

54 Designation Name A Former Municipal Incinerator B SWMU 9 Satellite Accumulation Area C SWMU 20 Sump Pump Basin D SWMU 21 Media Blaster E SWMU 9 Satellite Accumulation Area F SWMU 2 Paint Solvent Waste UST Piping G SWMU 3 & 4 Vapor Degreaser Unit/Drums H SWMU 3 & 4 Vapor Degreaser Unit/Drums I Former 1,500-Gallon TCE AST J Former 550-Gallon Diesel Fuel AST K 500-Gallon Diesel Fuel UST AIP L 3,000-Gallon Gasoline UST AIP M 5,500-Gallon Gasoline UST AIP N 15,000-Gallon Fuel Oil UST AIP O 8,000-Gallon Fuel Oil UST AIP P 15,000-Gallon Fuel Oil UST AIP Q Former Waste Paint Solvent UST R Former Waste Paint Solvent UST S Former 1,000-Gallon Gasoline UST T 15,000-Gallon Fuel Oil UST AIP U 500-Gallon Fuel Oil UST AIP V Former 2,000-Gallon Fuel Oil UST

55 Designation Name A Former Municipal Incinerator B SWMU 9 Satellite Accumulation Area C SWMU 20 Sump Pump Basin D SWMU 21 Media Blaster E SWMU 9 Satellite Accumulation Area F SWMU 2 Paint Solvent Waste UST Piping G SWMU 3 & 4 Vapor Degreaser Unit/Drums H SWMU 3 & 4 Vapor Degreaser Unit/Drums I Former 1,500-Gallon TCE AST J Former 550-Gallon Diesel Fuel AST K 500-Gallon Diesel Fuel UST AIP L 3,000-Gallon Gasoline UST AIP M 5,500-Gallon Gasoline UST AIP N 15,000-Gallon Fuel Oil UST AIP O 8,000-Gallon Fuel Oil UST AIP P 15,000-Gallon Fuel Oil UST AIP Q Former Waste Paint Solvent UST R Former Waste Paint Solvent UST S Former 1,000-Gallon Gasoline UST T 15,000-Gallon Fuel Oil UST AIP U 500-Gallon Fuel Oil UST AIP V Former 2,000-Gallon Fuel Oil UST

56 Designation Name A Former Municipal Incinerator B SWMU 9 Satellite Accumulation Area C SWMU 20 Sump Pump Basin D SWMU 21 Media Blaster E SWMU 9 Satellite Accumulation Area F SWMU 2 Paint Solvent Waste UST Piping G SWMU 3 & 4 Vapor Degreaser Unit/Drums H SWMU 3 & 4 Vapor Degreaser Unit/Drums I Former 1,500-Gallon TCE AST J Former 550-Gallon Diesel Fuel AST K 500-Gallon Diesel Fuel UST AIP L 3,000-Gallon Gasoline UST AIP M 5,500-Gallon Gasoline UST AIP N 15,000-Gallon Fuel Oil UST AIP O 8,000-Gallon Fuel Oil UST AIP P 15,000-Gallon Fuel Oil UST AIP Q Former Waste Paint Solvent UST R Former Waste Paint Solvent UST S Former 1,000-Gallon Gasoline UST T 15,000-Gallon Fuel Oil UST AIP U 500-Gallon Fuel Oil UST AIP V Former 2,000-Gallon Fuel Oil UST

57 Designation A B C D E F G H I J K L M N O P Q R S T U V Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST

58 Designation Name A Former Municipal Incinerator B SWMU 9 Satellite Accumulation Area C SWMU 20 Sump Pump Basin D SWMU 21 Media Blaster E SWMU 9 Satellite Accumulation Area F SWMU 2 Paint Solvent Waste UST Piping G SWMU 3 & 4 Vapor Degreaser Unit/Drums H SWMU 3 & 4 Vapor Degreaser Unit/Drums I Former 1,500-Gallon TCE AST J Former 550-Gallon Diesel Fuel AST K 500-Gallon Diesel Fuel UST AIP L 3,000-Gallon Gasoline UST AIP M 5,500-Gallon Gasoline UST AIP N 15,000-Gallon Fuel Oil UST AIP O 8,000-Gallon Fuel Oil UST AIP P 15,000-Gallon Fuel Oil UST AIP Q Former Waste Paint Solvent UST R Former Waste Paint Solvent UST S Former 1,000-Gallon Gasoline UST T 15,000-Gallon Fuel Oil UST AIP U 500-Gallon Fuel Oil UST AIP V Former 2,000-Gallon Fuel Oil UST

59

60

61 890!( MW-37!( Ù STREET SG !( Former Gehl Co. West Plant ED 896 P-39 Ù SG , !( Ù SG-101 <4.0 MW-36 LINWOOD Ù SG-100 <3.8!( EXPLANATION Contour05_ 888!( Sanitary Manhole Sanitary Sewer Force Main Line UtilityPole05 Sidewalk05 FenceBarrier P-38 ED Ù SG Monitor MW_coords$ well location Eventsand designation. Piezometerslocation and designation. Soil_Gas_Probes location and designation. Property address. Topographic contour interval = 2 feet Datum = Mean Sea Level ,600 Reported Trichloroethene concentration in soil gas sample (ug/m3). 898 TITLE: 304 SCALE 1 inch = 60 feet SOIL GAS PROBES LOCATIONS AND TRICHLOROETHENE RESULTS LOCATION: FORMER GEHL CO., TIF DISTRICT #12, WEST BEND, WISCONSIN CHECKED M.R.N. DRAFTED M.A.M. PROJECT DATE 08/12/2011 Feet FIGURE: 13 P:\City of West Bend\Gehl Brownfield TIF 12\GIS_files\mxd_Files\Soil Gas Figure mxd

62

63

64 N MANUFACTURING AND OFFICE BUILDING (WEST PLANT) ENGINEERING AND RESEARCH BUILDING EXPLANATION PHASE II MONITOR WELL LOCATION AND DESIGNATION MONITOR WELL LOCATION AND DESIGNATION TEMPORARY WELL LOCATION AND DESIGNATION PIEZOMETER LOCATION AND DESIGNATION APPROXIMATE LOCATION OF SOLID WASTE MANAGEMENT UNIT / AREA OF CONCERN APPROXIMATE LOCATION OF REMOVED OR ABANDONED STORAGE TANK EXTENT OF VINYL CHLORIDE IMPACTS ABOVE 2.0 ug/l (10x ES) EXTENT OF TRICHLOROETHENE IMPACTS ABOVE 50 ug/l (10x ES) TITLE: LOCATION: 0 SCALE Feet ALTERNATIVE GW-4 BIOREMEDIATION TIF DISTRICT # 12, WEST BEND, WISCONSIN 340 PROPOSED 50' INJECTION WELL SPACING CHECKED DRAFTED MRN HJW PROJECT DATE 1/24/12 FIGURE: 16 S:\CAD\City of West Bend\3-7-11\ Fig16B.dwg

65 TABLES

66 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site 1,1,1-Trichloroethane 1,2,4-Trimethylbenzene 1,2-Dichlorobenzene 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene Parameter Units ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Date Min Borehole ID Sampled RCL GP-1A 8' 10/15/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP-2 4' 10/15/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP-3A 4' 10/15/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP-3A 8' 10/15/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP-6 8' 10/15/08 < <25.0 < J 49.0J 148J < < J GP-8 4' 10/17/08 < <44.4 <25.0 < < < <25.0 <25.0 <40.4 < GP-8 10' 10/17/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-1 4' 10/17/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-1 7' 10/17/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-2B 4' 10/17/08 < J < J <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <40.4 <25.0 <25.0 GPTW-2B 8' 10/17/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 < J 29.9J < J <25.0 < <25.0 GPTW-3C 4' 10/20/08 < < < < < < GPTW-3C 9' 10/20/08 < < < J < J 1490 < GPTW-4B 4' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-4B 8' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-5 4' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-5 8' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-6 4' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-6 8' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-7 4' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-7 7' 10/20/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-8 4' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-8 8' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-9 6' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-10 4' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-10 6' 10/21/ <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 cis-1,2-dichloroethene Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene

67 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site Parameter Units Date Min Borehole ID Sampled RCL GP-1A 8' 10/15/08 GP-2 4' 10/15/08 GP-3A 4' 10/15/08 GP-3A 8' 10/15/08 GP-6 8' 10/15/08 GP-8 4' 10/17/08 GP-8 10' 10/17/08 GPTW-1 4' 10/17/08 GPTW-1 7' 10/17/08 GPTW-2B 4' 10/17/08 GPTW-2B 8' 10/17/08 GPTW-3C 4' 10/20/08 GPTW-3C 9' 10/20/08 GPTW-4B 4' 10/20/08 GPTW-4B 8' 10/20/08 GPTW-5 4' 10/20/08 GPTW-5 8' 10/20/08 GPTW-6 4' 10/20/08 GPTW-6 8' 10/20/08 GPTW-7 4' 10/20/08 GPTW-7 7' 10/20/08 GPTW-8 4' 10/21/08 GPTW-8 8' 10/21/08 GPTW-9 6' 10/21/08 GPTW-10 4' 10/21/08 GPTW-10 6' 10/21/08 p-isopropyltoluene sec-butylbenzene Tetrachloroethene Toluene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg < <25.0 < <25.0 <25.0 < <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < < J <25.0 <25.0 <25.0 < < <100 < < <125 < <25.0 <25.0 <25.0 < < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 < J < <25.0 < < < Total Xylenes Total VOCs

68 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site 1,1,1-Trichloroethane 1,2,4-Trimethylbenzene 1,2-Dichlorobenzene 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene Parameter Units ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Date Min Borehole ID Sampled RCL GPTW-11 5' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-12 2' 10/21/ <100 <178 <100 <100 <100 <100 <100 <100 <100 <100 <100 <162 <100 <100 GPTW-12 7' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-13 6' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW ' 10/22/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW ' 10/22/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-16 4' 10/21/ J <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 < J 42.0J 81.8 <40.4 < J GPTW ' 10/21/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GPTW-17 4' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-17 13' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-18 4' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-18 12' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-19 4' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-19 11' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-20 4' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GPTW-20 11' 08/14/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-1 4' 10/23/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-2 4' 10/23/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <40.4 <25.0 <25.0 MW-2 8' 10/23/08 <25.0 <25.0 <44.4 <25.0 <25.0 < J <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-3 4' 10/23/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-4 4' 10/23/08 < <44.4 <25.0 < < <25.0 <25.0 < J MW-4 8' 10/23/08 < < <200 <200 < < < <200 MW-5 2' 10/28/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <25.0 <40.4 <25.0 <25.0 MW-5 8' 10/28/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 MW-6 4' 10/28/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 MW-6 7' 10/28/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 cis-1,2-dichloroethene Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene

69 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site Parameter Units Date Min Borehole ID Sampled RCL GPTW-11 5' 10/21/08 GPTW-12 2' 10/21/08 GPTW-12 7' 10/21/08 GPTW-13 6' 10/21/08 GPTW ' 10/22/08 GPTW ' 10/22/08 GPTW-16 4' 10/21/08 GPTW ' 10/21/08 GPTW-17 4' 08/14/09 GPTW-17 13' 08/14/09 GPTW-18 4' 08/14/09 GPTW-18 12' 08/14/09 GPTW-19 4' 08/14/09 GPTW-19 11' 08/14/09 GPTW-20 4' 08/14/09 GPTW-20 11' 08/14/09 MW-1 4' 10/23/08 MW-2 4' 10/23/08 MW-2 8' 10/23/08 MW-3 4' 10/23/08 MW-4 4' 10/23/08 MW-4 8' 10/23/08 MW-5 2' 10/28/08 MW-5 8' 10/28/08 MW-6 4' 10/28/08 MW-6 7' 10/28/08 p-isopropyltoluene sec-butylbenzene Tetrachloroethene Toluene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg <100 < < < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 < J < <25.0 <25.0 < < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 < J <25.0 < J 558J <200 <200 <200 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < Total Xylenes Total VOCs

70 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site 1,1,1-Trichloroethane 1,2,4-Trimethylbenzene 1,2-Dichlorobenzene 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene Parameter Units ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Date Min Borehole ID Sampled RCL MW-7 1-2' 10/28/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 MW-7 5.5' 10/28/08 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-31 2' 02/18/ <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <25.0 <40.4 <25.0 <25.0 MW-31 10' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-31 15' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-32 4' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-32 10' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-32 16' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-33 4' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-33 10' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-33 16' 02/18/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-34 4' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-34 10' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 P ' 09/16/10 < < <100 < J 635 <200 < < P ' 09/14/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 P ' 09/15/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 I 4' 02/17/09 < < J <25.0 <25.0 < < < <40.4 < I 10' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 II 4' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 II 8' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 II 10' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 III 4' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 III 8' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 < J 32.7J < <25.0 III 10' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 < <25.0 IV 2-4' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 IV 8' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 cis-1,2-dichloroethene Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene

71 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site Parameter Units Date Min Borehole ID Sampled RCL MW-7 1-2' 10/28/08 MW-7 5.5' 10/28/08 MW-31 2' 02/18/09 MW-31 10' 02/18/09 MW-31 15' 02/18/09 MW-32 4' 02/18/09 MW-32 10' 02/18/09 MW-32 16' 02/18/09 MW-33 4' 02/18/09 MW-33 10' 02/18/09 MW-33 16' 02/18/09 MW-34 4' 02/16/09 MW-34 10' 02/16/09 P ' 09/16/10 P ' 09/14/10 P ' 09/15/10 I 4' 02/17/09 I 10' 02/17/09 II 4' 02/17/09 II 8' 02/17/09 II 10' 02/17/09 III 4' 02/17/09 III 8' 02/17/09 III 10' 02/17/09 IV 2-4' 02/17/09 IV 8' 02/17/09 p-isopropyltoluene sec-butylbenzene Tetrachloroethene Toluene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 < < < <25.0 <25.0 <25.0 < J < <100 < J <100 < <25.0 < J < < <25.0 <25.0 < J <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < < J <25.0 <25.0 <25.0 < Total Xylenes Total VOCs

72 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site 1,1,1-Trichloroethane 1,2,4-Trimethylbenzene 1,2-Dichlorobenzene 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene Parameter Units ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Date Min Borehole ID Sampled RCL IV 10' 02/17/09 < <444 <250 <250 <250 < J <250 <250 < <250 V 2' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 V 8' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 V 11' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 VI 4' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 VI 8' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 VII 4' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 VII 10' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 VIII 4' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 VIII 8' 02/16/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 IX 4' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 IX 8' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 IX 12' 02/17/09 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP-9 2-4' 02/16/10 < < < < J 890 <25.0 <25.0 < J 55.8J GP-9 6-8' 02/16/10 < < <50.0 <50.0 < < < GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 < <25.0 <25.0 <25.0 <50.0 < J <40.4 <25.0 <25.0 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 < < < < < GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 < J <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <40.4 <25.0 <25.0 cis-1,2-dichloroethene Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene

73 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site Parameter Units Date Min Borehole ID Sampled RCL IV 10' 02/17/09 V 2' 02/16/09 V 8' 02/16/09 V 11' 02/16/09 VI 4' 02/16/09 VI 8' 02/16/09 VII 4' 02/16/09 VII 10' 02/16/09 VIII 4' 02/16/09 VIII 8' 02/16/09 IX 4' 02/17/09 IX 8' 02/17/09 IX 12' 02/17/09 GP-9 2-4' 02/16/10 GP-9 6-8' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 p-isopropyltoluene sec-butylbenzene Tetrachloroethene Toluene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg J 565J <250 <250 <250 < <25.0 <25.0 < J <25.0 < J 190 < J <50.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < < <25.0 < <25.0 <25.0 <25.0 < < <25.0 <25.0 <25.0 < J < Total Xylenes Total VOCs

74 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site 1,1,1-Trichloroethane 1,2,4-Trimethylbenzene 1,2-Dichlorobenzene 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene Parameter Units ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Date Min Borehole ID Sampled RCL GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 < J <44.4 <25.0 < J <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 < <50.0 < J < <25.0 GP ' 02/16/10 < < J < J J 670 <25.0 <25.0 < J 257 GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/16/10 < < J < < J 491 <25.0 <25.0 < J 43.9J GP ' 02/16/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 < J <50.0 < < <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 < < <1000 <1000 < <1000 <1000 < GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/ J <222 <125 <125 <125 <125 <125 <125 <250 < J <202 < J GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/ <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 cis-1,2-dichloroethene Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene

75 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site Parameter Units Date Min Borehole ID Sampled RCL GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/16/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 GP ' 02/17/10 p-isopropyltoluene sec-butylbenzene Tetrachloroethene Toluene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 < <25.0 < <25.0 <25.0 < <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <1000 <1000 <1000 <1000 <1000 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <125 < < < <25.0 <25.0 <25.0 < J < <25.0 <25.0 <25.0 < < Total Xylenes Total VOCs

76 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site 1,1,1-Trichloroethane 1,2,4-Trimethylbenzene 1,2-Dichlorobenzene 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene Parameter Units ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg Date Min Borehole ID Sampled RCL GP ' 02/17/10 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < J <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <40.4 <25.0 <25.0 GP ' 02/17/ <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/ <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 GP ' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 MW-3R 2-4' 02/17/11 <25.0 <25.0 <44.4 <25.0 <25.0 <25.0 <25.0 <25.0 <25.0 <50.0 <25.0 <25.0 <40.4 <25.0 <25.0 cis-1,2-dichloroethene Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene

77 Table 1. Summary of Soil Samples VOCs Analytical Results, Former Gehl Co. TIF District #12 Site Parameter Units Date Min Borehole ID Sampled RCL GP ' 02/17/10 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 GP ' 02/17/11 MW-3R 2-4' 02/17/11 p-isopropyltoluene sec-butylbenzene Tetrachloroethene Toluene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg ug/kg <25.0 < J <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 <25.0 <25.0 < <25.0 <25.0 <25.0 < < <25.0 <25.0 < <25.0 < Notes: ug/kg = micrograms per kilogram, which is equivalent to parts per billion (ppb) J = Estimated concentration above the adjusted method detection limit and below the adjusted practical quantitation limit. Min RCL = Minimum Residual Contaminant Level calculated from US EPA Soil Screening Guidance for Chemicals website using WDNR default values. Bold values exceed the Min RCL. Methylene Chloride is a common laboratory contaminant. Only detected VOCs are listed on the Table. Total Xylenes Total VOCs

78 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS GPTW-1 10/31/08 <0.92 < <0.57 <0.97 <0.36 < <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 GPTW-1 02/25/09 <0.92 < <0.57 < < <0.56 <0.97 <1.3 < <0.81 < GPTW-1 06/01/09 < <0.57 < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 GPTW-2B 10/31/08 <0.92 < < < <0.56 <0.97 <1.3 < <0.81 < GPTW-2B 02/25/09 <1.8 < < < <1.1 <1.9 <2.6 <0.48 <1.7 <1.6 < GPTW-2B 02/25/09 DUP < < < <0.56 <0.97 <1.3 < <0.81 < GPTW-2B 06/03/09 <1.8 < < < <1.1 <1.9 <2.6 <0.48 <1.7 <1.6 < GPTW-15 10/31/08 <0.92 <0.90 <0.75 < < <0.41 <0.56 <0.97 < <0.83 <0.81 < GPTW-15 10/31/08 DUP <0.92 <0.90 <0.75 < < <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 < GPTW-15 02/25/09 <0.92 <0.90 <0.75 < <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 < GPTW-15 06/02/09 <0.92 <0.90 <0.75 < <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 < GPTW-15 06/02/09 DUP <0.92 <0.90 <0.75 < <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 < GPTW-17 08/17/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 GPTW-18 08/17/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 < <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 GPTW-19 08/17/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 GPTW-20 08/17/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-A 10/31/08 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-A 02/25/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-A 03/04/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-1 10/31/08 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-1 02/24/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-1 06/01/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-1 02/23/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-1 02/24/11 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-2 10/31/08 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 < <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

79 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL GPTW-1 10/31/08 GPTW-1 02/25/09 GPTW-1 06/01/09 GPTW-2B 10/31/08 GPTW-2B 02/25/09 GPTW-2B 02/25/09 DUP GPTW-2B 06/03/09 GPTW-15 10/31/08 GPTW-15 10/31/08 DUP GPTW-15 02/25/09 GPTW-15 06/02/09 GPTW-15 06/02/09 DUP GPTW-17 08/17/09 GPTW-18 08/17/09 GPTW-19 08/17/09 GPTW-20 08/17/09 MW-A 10/31/08 MW-A 02/25/09 MW-A 03/04/10 MW-1 10/31/08 MW-1 02/24/09 MW-1 06/01/09 MW-1 02/23/10 MW-1 02/24/11 MW-2 10/31/08 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < < <0.97 < < < < <1.9 <0.90 <1.3 < < < <0.97 < < < <1.9 <0.90 <1.3 <1.8 <0.96 < <0.45 <0.67 <0.89 <0.48 < < <0.45 <0.67 <0.89 <0.48 < < < <0.97 <0.45 <0.67 <0.89 <0.48 < < <0.97 <0.45 <0.67 <0.89 <0.48 < < <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 < <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 < < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 < <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

80 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS MW-2 02/24/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-2 06/01/09 <0.92 < <0.97 <0.36 < <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-2 02/27/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-2 03/02/11 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-3 10/31/08 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-3 02/24/09 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-3 02/24/09 DUP < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-3 06/01/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-3R 02/25/11 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-4 10/31/08 <0.92 <0.90 <0.75 <0.57 < <0.41 < <1.3 < <0.81 < MW-4 02/24/09 <1.8 <1.8 <1.5 < < <1.1 <1.9 <2.6 <0.48 <1.7 <1.6 < MW-4 06/01/09 <1.8 <1.8 <1.5 < < < <2.6 <0.48 <1.7 <1.6 < MW-4 02/23/10 <2.3 <2.2 <1.9 < < <1.4 <2.4 <3.2 <0.60 <2.1 <2.0 < MW-4 02/24/11 <2.3 <2.2 <1.9 < < <3.2 <0.60 <2.1 <2.0 < MW-5 10/31/08 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-5 02/24/09 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-5 06/01/09 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-5 02/27/10 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-5 03/02/11 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-6 10/31/08 <4.6 < <2.8 <4.8 <1.8 <4.2 <2.0 <2.8 <4.8 <6.5 < <4.0 <5.0 <2.7 <3.0 <9.0 MW-6 02/26/09 <9.2 < <9.7 <3.6 <8.3 <4.1 <5.6 <9.7 <13 < <8.1 <9.9 <5.4 <5.9 <18 MW-6 06/02/09 <9.2 < <5.7 <9.7 <3.6 <8.3 <4.1 <5.6 <9.7 <13 < <8.1 <9.9 <5.4 <5.9 <18 MW-6 02/24/10 <9.2 < <9.7 <3.6 <8.3 <4.1 <5.6 <9.7 <13.0 < <8.1 <9.9 <5.4 <5.9 <18.0 MW-6 02/24/10 DUP <9.2 < <9.7 <3.6 <8.3 <4.1 <5.6 <9.7 <13.0 < <8.1 <9.9 <5.4 <5.9 <18.0 MW-6 03/01/11 <9.2 < <9.7 <3.6 <8.3 <4.1 <5.6 <9.7 <13.0 < <8.1 <9.9 <5.4 <5.9 <18.0 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

81 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL MW-2 02/24/09 MW-2 06/01/09 MW-2 02/27/10 MW-2 03/02/11 MW-3 10/31/08 MW-3 02/24/09 MW-3 02/24/09 DUP MW-3 06/01/09 MW-3R 02/25/11 MW-4 10/31/08 MW-4 02/24/09 MW-4 06/01/09 MW-4 02/23/10 MW-4 02/24/11 MW-5 10/31/08 MW-5 02/24/09 MW-5 06/01/09 MW-5 02/27/10 MW-5 03/02/11 MW-6 10/31/08 MW-6 02/26/09 MW-6 06/02/09 MW-6 02/24/10 MW-6 02/24/10 DUP MW-6 03/01/11 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < < < <0.97 <0.45 <0.67 < < < <1.9 < <1.8 <0.96 < < <1.8 <1.9 < <1.8 <0.96 < < <2.4 < <2.2 <1.2 < < <2.4 < <2.2 <1.2 < < <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <2.2 <4.4 <4.6 <4.0 <4.2 <3.4 <4.4 <4.8 <2.2 < < <4.3 <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 < < <4.3 <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 < < <4.3 <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 < < <4.3 <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 < < <4.3 <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 < < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

82 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS MW-6 03/01/11 DUP <9.2 < <9.7 <3.6 <8.3 <4.1 <5.6 <9.7 <13.0 < <8.1 <9.9 <5.4 <5.9 <18.0 P-39 09/30/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 P-39 03/01/11 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-7 10/31/08 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-7 02/25/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-7 06/02/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-7 02/25/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-7 03/01/11 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 < < <0.24 < <0.99 <0.54 <0.59 <1.8 MW-31 02/26/09 < < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-31 06/03/09 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-31 02/24/10 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-31 02/28/11 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-32 02/26/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 < <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-32 06/03/09 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-32 02/24/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 < <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-32 02/28/11 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 < <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-33 02/26/09 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-33 06/03/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-33 02/24/10 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-33 02/28/11 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-34 02/26/09 < <0.57 < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-34 06/02/09 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-34 02/23/10 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-34 03/02/11 < <0.57 < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-35 02/23/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

83 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL MW-6 03/01/11 DUP P-39 09/30/10 P-39 03/01/11 MW-7 10/31/08 MW-7 02/25/09 MW-7 06/02/09 MW-7 02/25/10 MW-7 03/01/11 MW-31 02/26/09 MW-31 06/03/09 MW-31 02/24/10 MW-31 02/28/11 MW-32 02/26/09 MW-32 06/03/09 MW-32 02/24/10 MW-32 02/28/11 MW-33 02/26/09 MW-33 06/03/09 MW-33 02/24/10 MW-33 02/28/11 MW-34 02/26/09 MW-34 06/02/09 MW-34 02/23/10 MW-34 03/02/11 MW-35 02/23/10 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <4.3 <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 < < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 < < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 < < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 < < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < < <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

84 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS MW-35 02/24/11 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 P-38 09/30/10 <0.92 < < <0.83 <0.41 <0.56 <0.97 < <0.81 <0.99 <0.54 <0.59 <1.8 P-38 02/24/11 <0.92 < <0.57 < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 SUMP 02/28/11 < <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-36 02/23/10 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-36 03/01/11 < <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-37 02/24/10 < < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-37 03/01/11 < < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-15 10/31/08 < < <0.83 <0.41 < <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-15 02/25/09 < < <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-15 06/02/09 < < <2.1 <1.0 <1.4 <2.4 <3.2 <0.60 <2.1 <2.0 <2.5 <1.4 <1.5 <4.5 MW-15 02/25/10 < < <2.1 <1.0 <1.4 <2.4 <3.2 <0.60 <2.1 <2.0 <2.5 <1.4 <1.5 <4.5 MW-15 03/01/11 < < <8.3 <4.1 <5.6 <9.7 <13.0 <2.4 <8.3 <8.1 <9.9 <5.4 <5.9 <18.0 MW-16 10/31/08 < < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-16 02/25/09 < < <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-16 06/02/09 < <2.4 <0.90 <2.1 <1.0 <1.4 <2.4 <3.2 <0.60 <2.1 <2.0 <2.5 <1.4 <1.5 <4.5 MW-16 02/26/10 < < <1.7 <0.82 <1.1 <1.9 <2.6 <0.48 <1.7 <1.6 <2.0 <1.1 <1.2 <3.6 MW-16 03/01/11 < <1.9 <0.72 <1.7 < <1.9 <2.6 <0.48 < <2.0 <1.1 <1.2 <3.6 MW-16 03/01/11 DUP < <1.9 <0.72 <1.7 < <1.9 <2.6 <0.48 < <2.0 <1.1 <1.2 <3.6 MW-17 10/31/08 < <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-17 02/26/09 < <4.8 <1.8 <4.2 <2.0 <2.8 <4.8 <6.5 < <4.0 <5.0 <2.7 <3.0 <9.0 MW-17 06/02/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-17 02/25/10 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

85 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL MW-35 02/24/11 P-38 09/30/10 P-38 02/24/11 SUMP 02/28/11 MW-36 02/23/10 MW-36 03/01/11 MW-37 02/24/10 MW-37 03/01/11 MW-15 10/31/08 MW-15 02/25/09 MW-15 06/02/09 MW-15 02/25/10 MW-15 03/01/11 MW-16 10/31/08 MW-16 02/25/09 MW-16 06/02/09 MW-16 02/26/10 MW-16 03/01/11 MW-16 03/01/11 DUP MW-17 10/31/08 MW-17 02/26/09 MW-17 06/02/09 MW-17 02/25/10 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <2.2 <2.3 <2.0 <2.1 <1.7 <2.2 <2.4 <1.1 <1.7 < < <2.2 <2.3 <2.0 <2.1 <1.7 <2.2 <2.4 <1.1 <1.7 < < <8.9 <9.3 <8.1 <8.3 <6.7 <8.9 <9.7 <4.5 <6.7 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 < <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 < <0.67 < < <1.1 <2.2 <2.3 <2.0 <2.1 <1.7 <2.2 <2.4 <1.1 <1.7 < < <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 <1.3 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 <1.3 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 <1.3 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 < < < <2.2 <4.4 <4.6 <4.0 <4.2 <3.4 <4.4 <4.8 <2.2 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 < < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

86 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS MW-17 03/23/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 P-40 09/30/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 P-40 03/23/11 <0.92 <0.9 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-18 10/31/08 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-18 02/26/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-18 06/03/09 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-18 06/03/09 DUP < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-18 02/25/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-18 02/25/10 DUP < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-18 02/24/11 < <0.97 <0.36 <0.83 < < <0.24 < <0.99 <0.54 <0.59 <1.8 MW-21 02/26/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-21 03/23/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-47 03/01/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-48 06/03/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-48 03/23/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-48 02/24/11 < <0.75 <0.57 <0.97 <0.36 <0.83 < < <0.24 < <0.99 <0.54 <0.59 <1.8 MW-48 02/24/11 DUP < <0.75 <0.57 <0.97 <0.36 <0.83 < < <0.24 < <0.99 <0.54 <0.59 <1.8 MW-49 06/03/09 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-49 03/23/10 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-49 02/24/11 < <0.97 <0.36 <0.83 < <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-51 06/03/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-51 02/26/10 < <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-51 03/01/11 < <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-52R 06/04/09 <1.8 < <1.9 <0.72 <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

87 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL MW-17 03/23/11 P-40 09/30/10 P-40 03/23/11 MW-18 10/31/08 MW-18 02/26/09 MW-18 06/03/09 MW-18 06/03/09 DUP MW-18 02/25/10 MW-18 02/25/10 DUP MW-18 02/24/11 MW-21 02/26/10 MW-21 03/23/11 MW-47 03/01/11 MW-48 06/03/09 MW-48 03/23/10 MW-48 02/24/11 MW-48 02/24/11 DUP MW-49 06/03/09 MW-49 03/23/10 MW-49 02/24/11 MW-51 06/03/09 MW-51 02/26/10 MW-51 03/01/11 MW-52R 06/04/09 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 <1.3 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 <1.3 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 < < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

88 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS MW-52R 03/01/10 < < <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-52R 03/01/11 < < <1.7 <0.82 <1.1 <1.9 <2.6 < <1.6 <2.0 <1.1 <1.2 <3.6 MW-53R 06/04/09 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-53R 03/01/10 < <0.97 <0.36 < < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-53R 03/01/11 < <0.97 <0.36 < <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-55R 06/04/09 < <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-55R 03/01/10 < <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-55R 03/01/11 < <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-57 06/26/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-57 03/23/10 < <0.97 <0.36 <0.83 <0.41 <0.56 < < <0.81 <0.99 <0.54 <0.59 <1.8 MW-57 02/25/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-59 06/26/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-59 03/23/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-59 02/25/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-62 06/26/09 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-62 03/23/10 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-62 02/25/11 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-42 06/04/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-42 06/04/09 DUP < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-42 02/26/10 < <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-42 02/24/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-43 06/04/09 < <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-43 02/26/10 <0.92 < <0.57 <0.97 <0.36 < < <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

89 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL MW-52R 03/01/10 MW-52R 03/01/11 MW-53R 06/04/09 MW-53R 03/01/10 MW-53R 03/01/11 MW-55R 06/04/09 MW-55R 03/01/10 MW-55R 03/01/11 MW-57 06/26/09 MW-57 03/23/10 MW-57 02/25/11 MW-59 06/26/09 MW-59 03/23/10 MW-59 02/25/11 MW-62 06/26/09 MW-62 03/23/10 MW-62 02/25/11 MW-42 06/04/09 MW-42 06/04/09 DUP MW-42 02/26/10 MW-42 02/24/11 MW-43 06/04/09 MW-43 02/26/10 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 < <0.86 <1.8 <1.9 <1.6 <1.7 <1.3 <1.8 <1.9 <0.90 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 <0.48 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

90 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 1,1,1,2-Tetrachloroethane 1,1,1-Trichloroethane 1,1-Dichloroethane 1,1-Dichloroethene 1,2,4-Trimethylbenzene 1,2-Dichloroethane 1,3,5-Trimethylbenzene Parameter Units ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l Date ES NS Well ID Sampled PAL NS MW-43 02/26/10 DUP <0.92 < <0.57 <0.97 <0.36 < < <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-43 02/25/11 <0.92 < <0.57 <0.97 <0.36 < < <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 MW-44 06/04/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-44 03/04/10 < <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-44 02/25/11 < <0.57 <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-44 02/25/11 DUP < <0.57 <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-45 03/04/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-45 02/25/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-46 06/04/09 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-46 03/04/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-46 02/25/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-63 06/04/09 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < < <0.54 <0.59 <1.8 MW-63 03/01/10 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < < <0.54 <0.59 <1.8 MW-63 02/25/11 < <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-64 06/04/09 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-64 03/01/10 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 < <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 MW-64 02/25/11 <0.92 < <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 TW /01/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 TW /01/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 TW /01/10 < <0.57 <0.97 <0.36 < <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 TW /01/10 DUP <0.92 < <0.57 <0.97 <0.36 < <0.56 <0.97 <1.3 < <0.81 <0.99 <0.54 <0.59 <1.8 TW /01/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 TW /01/10 <0.92 <0.90 <0.75 <0.57 <0.97 <0.36 <0.83 <0.41 <0.56 <0.97 <1.3 <0.24 <0.83 <0.81 <0.99 <0.54 <0.59 <1.8 Benzene Bromodichloromethane Chloroethane Chloroform Chloromethane cis-1,2-dichloroethene Dibromochloromethane Dichlorodifluoromethane Ethylbenzene Isopropylbenzene (Cumene) m&p-xylene

91 Table 2. Summary of Groundwater Samples VOCs Analytical Results, Former Gehl Co. Site, City of West Bend TIF District #12 Parameter Units Date ES Well ID Sampled PAL MW-43 02/26/10 DUP MW-43 02/25/11 MW-44 06/04/09 MW-44 03/04/10 MW-44 02/25/11 MW-44 02/25/11 DUP MW-45 03/04/10 MW-45 02/25/11 MW-46 06/04/09 MW-46 03/04/10 MW-46 02/25/11 MW-63 06/04/09 MW-63 03/01/10 MW-63 02/25/11 MW-64 06/04/09 MW-64 03/01/10 MW-64 02/25/11 TW /01/10 TW /01/10 TW /01/10 TW /01/10 DUP TW /01/10 TW /01/10 Methylene Chloride Naphthalene n-butylbenzene n-propylbenzene o-xylene p-isopropyltoluene sec-butylbenzene tert-butylbenzene Tetrachloroethene ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l ug/l NS NS NS NS NS NS NS NS NS NS <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 <0.89 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 < <0.67 < < <0.43 <0.89 <0.93 <0.81 <0.83 <0.67 <0.89 <0.97 <0.45 <0.67 < < Toluene trans-1,2-dichloroethene Trichloroethene Vinyl chloride Trimethylbenzenes (1,2,4- + 1,3,5-) Total Xylenes Total VOCs Total Chlorinated VOCs

92 Table 3. Identified Soil Areas at Former Gehl Site Name of Area Identified Contaminants Detailed RO Rationale for No Detailed RO Analysis Analysis in Section 5.0 Site Wide Arsenic, Mercury No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater West Plant - North Lead No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater Maintenance Garage South Lead No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater MW-2 to MW-4 Lead No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater Maintenance Garage South PVOCs Yes MW-4 PVOCs Yes MW-2 to MW-4 to GP-6 Benzo (a) pyrene No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater West Plant - North Benzo (a) pyrene No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater West Plant - Center Benzo (a) pyrene No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover, Not found in groundwater West Plant - North CVOCs Yes West Plant - Center CVOCs No Future Site Use, Building Cover, Gravel Cover, Clean Fill Cover West Plant Southeast Loading Docks CVOCs Yes Maintenance Garage East CVOCs Yes PVOCs: Petroleum Volatile Organic Compounds CVOCs: Chlorinated Volatile Organic Compounds

93 Table 4. Identified Groundwater Areas at Former Gehl Site Name of Area Identified Contaminants Source for Detailed RCL RO Rationale for No Detailed RO Analysis Analysis in Section 5.0 MW-6 West Plant Southeast Loading Docks CVOCs USEPA Yes MW-4 GPTW-2B Maintenance Garage South PVOCs USEPA No No Receptors, No Downgradient Migration, Natural Attenuation Adequate MW-15 West Plant North Boundary CVOCs USEPA No Include with immediately down gradient West Plant - North Area West Plant - North CVOCs USEPA Yes MW-52R Off Site West CVOCs USEPA No Off Site, Will benefit from source area (West Plant - North) GW remediation West Plant - South (Sump) CVOCs USEPA Yes West Half - Enginering Building CVOCs USEPA No No Receptors, Beneath Building, Natural Attenuation Adequate Indiana Avenue at Milwaukee River CVOCs USEPA No No Receptors, Off - Site, Natural Attenuation Adequate PVOCs: Petroleum Volatile Organic Compounds CVOCs: Chlorinated Volatile Organic Compounds

94 Table 5. Soil Remedial Action Decision Matrix Remedial Alternative Capability of Meeting Remedial Action Goals Score Timeframe for Achieving Cleanup Goals Score Implementability Regulatory/ Administrative Score Logistical Score Technical Score Relative Cost Score Retain for Detailed Analysis Total Score No Action Limited 0 Very Long 1 Very Difficult 1 Very Easy 5 Very Easy 5 Very Low 5 Yes 17 In-Place Capping Effective 2 Very Short 5 Moderate 3 Easy 4 Easy 4 Low 4 Yes 22 Consolidation On Site and Capping Excavation and On-Site Landfarming Chemical Oxidation via In-Situ Soil Mixing Excavation and Off-Site Disposal Effective 2 Very Short 5 Very Difficult 1 Difficult 2 Moderate 3 High 2 No 15 Effective 2 Moderate 3 Difficult 2 Difficult 2 Moderate 3 High 2 No 14 Effective 2 Short 4 Moderate 3 Moderate 3 Moderate 3 High 2 Yes 17 Effective 2 Very Short 5 Very Easy 5 Moderate 3 Easy 4 Moderate 3 Yes 22 Soil Vapor Extraction Effective 2 Moderate 3 Moderate 3 Moderate 3 Moderate 3 High 2 Yes 16 Electrical Resistance Heating Effective 2 Moderate 3 Moderate 3 Very Difficult 1 Very Difficult 1 Very High 1 No 11

95 Table 6. Groundwater Remedial Action Decision Matrix Timeframe for Achieving Cleanup Goals Implementability Regulatory/ Administrative Score Logistical Score Technical Score Capability of Meeting Relative Total Remedial Alternative Remedial Action Goals Score Score Cost Score Score No Action Very Limited 0 Very Long 1 Very Difficult 1 Very Easy 5 Very Easy 5 Very Low 5 Yes 17 Natural Attenuation Only Limited 0 Very Long 1 Very Difficult 1 Easy 4 Moderate 3 Moderate 3 Yes 12 Groundwater Pump and Treat Effective 1 Modreate 4 Moderate 3 Moderate 3 Moderate 3 Moderate 3 Yes 17 In Situ Biological Treatment Effective 1 Short 5 Moderate 3 Difficult 2 Difficult 2 Very High 1 Yes 14 In Situ Chemical Oxidation Effective 1 Short 5 Difficult 2 Very Difficult 1 Difficult 2 Very High 1 No 12 Retain for Detailed Analysis

96 Table 7. Summary of Remedial Alternative Costs Soil Remediation Capital Cost O&M Cost Total NPV Maintenance Garage - South Area Alternative S-1 No Action $0 $0 $0 Alternative S-2 Capping $46,151 $3,458 $49,609 Alternative S-3 Excavation & Disposal $339,749 $0 $339,749 Alternative S-4 Soil Vapor Extraction $268,793 $98,400 $367,193 West Plant - North Area Alternative S-1 No Action $0 $0 $0 Alternative S-2 Capping $16,625 $3,458 $20,083 Alternative S-3 Excavation & Disposal $1,059,013 $0 $1,059,013 Alternative S-4 Soil Vapor Extraction $671,650 $148,800 $820,450 West Plant - Southeast Loading Dock Alternative S-1 No Action $0 $0 $0 Alternative S-2 Capping $16,625 $3,458 $20,083 Alternative S-3 Excavation & Disposal $35,218 $0 $35,218 Alternative S-4 Soil Vapor Extraction $153,748 $55,200 $208,948 Groundwater Remediation Maintenance Garage - East Area Alternative S-1 No Action $0 $0 $0 Alternative S-2 Capping $16,625 $3,458 $20,083 Alternative S-3 Excavation & Disposal $378,851 $0 $378,851 Alternative S-4 Soil Vapor Extraction $302,575 $73,200 $375,775 Sitewide Alternative GW-1 No Action $0 $0 $0 Alternative GW-2 Pump & Treat w/ MNA $202,439 $1,508,554 $1,710,993 Alternative GW-3 Pump & Treat $607,092 $2,699,973 $3,307,065 Alternative GW-4 Bioremediation w/ MNA $555,345 $691,680 $1,247,025

97 APPENDICES

98 APPENDIX A REFERENCE FIGURES

99 GPTW-16 4' 6.5' Arsenic Lead Mercury J GPTW-12 2' 7' Arsenic Lead Mercury GPTW-14 4' Arsenic NA Lead 8.5 Mercury NA GPTW-11 5' Arsenic 1.7 Lead 2.1 Mercury.0096J GPTW-13 6' Arsenic 1.5 Lead 1.6 Mercury.0087J GPTW-10 4' 6' Arsenic 6.2J 2.3 Lead Mercury GPTW-8 4' 8' Arsenic Lead Mercury.006J GPTW-6 4' 8' Arsenic Lead Mercury.0059J GPTW-5 4' 8' Arsenic Lead Mercury MW-4 4' 8' Arsenic NA NA Lead Mercury NA NA GP-8 4' 10' Arsenic NA NA Lead Mercury NA NA GPTW-9 6' Arsenic 1.7 Lead 2 Mercury GPTW-7 4' 7' Arsenic Lead Mercury J Designation A B C D E F G H I J K L M N O P Q R S T U V GPTW-3 4' 9' Arsenic NA NA Lead Mercury NA NA Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST MW-3 4' Arsenic 1.4 Lead 1.4 Mercury.0022J MW-1 4' Arsenic 3.4 Lead 29.8 Mercury GP-2 4' Arsenic 3.7 Lead 31.9 Mercury 0.51 GP-6 8' Arsenic 3.5 Lead 1660 Mercury 20.9 GP-1 8' Arsenic 5.2 Lead 87.5 Mercury 0.12 GP-3 4' 8' Arsenic Lead Mercury J MW-2 4' 8' Arsenic Lead Mercury GP-1 8' Arsenic 5.2 Lead 87.5 Mercury 0.12

100 MW-7 1-2' 5.5' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-16 4' 6.5' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene 97.8 <25.0 m&p-xylene 89.1J <25.0 GPTW ' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 GPTW-12 2' 7' Benzene <100 <25.0 Ethylbenzene <100 <25.0 Toluene <100 <25.0 m&p-xylene <100 <25.0 MW-31 2' 10' 15' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene 34.5J <25.0 <25.0 GPTW ' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 GPTW-19 4' 11' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <50.0 <50.0 GPTW-11 5' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 GPTW-10 4' 6' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-3C 4' 9' Benzene J Ethylbenzene Toluene m&p-xylene GPTW-2B 4' 8' Benzene <25.0 <25.0 Ethylbenzene < J Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-8 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-6 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 MW-5 2' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene 75.3J <25.0 I 4' 10' Benzene <25.0 <25.0 Ethylbenzene 128 <25.0 Toluene 45.4J <25.0 m&p-xylene 391 <25.0 II 4' 8' 10' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene <25.0 <25.0 <25.0 III 4' 8' 10' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene < J <25.0 GPTW-9 6' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 GPTW-5 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 MW-4 4' 8' Benzene 484 <200 Ethylbenzene Toluene 48.0J <200 m&p-xylene GP-8 4' 10' Benzene 212 <25.0 Ethylbenzene 81.2 <25.0 Toluene 862 <25.0 m&p-xylene 267 <25.0 GPTW-13 6' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 MW-33 4' 10' 16' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene <25.0 <25.0 <25.0 IX 4' 8' 12' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene <25.0 <25.0 <25.0 GPTW-7 4' 7' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-4B 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 MW-1 4' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 MW-32 4' 10' 16' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene <25.0 <25.0 <25.0 GPTW-17 4' 13' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <50.0 <50.0 MW-6 4' 7' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 IV 2-4' 8' 10' * Benzene <25.0 <25.0 <250 Ethylbenzene <25.0 < Toluene <25.0 <25.0 <250 m&p-xylene <25.0 <25.0 <250 GPTW-1 4' 7' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GP-2 4' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 GP-1A 8' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 Designation A B C D E F G H I J K L M N O P Q R S T U V MW-34 4' 10' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-18 4' 12' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <50.0 <50.0 Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST MW-2 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 V 2' 8' 11' Benzene <25.0 <25.0 <25.0 Ethylbenzene <25.0 <25.0 <25.0 Toluene <25.0 <25.0 <25.0 m&p-xylene <25.0 <25.0 <25.0 VIII 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GPTW-20 4' 11' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <50.0 <50.0 GP-6 8' * Benzene <25.0 Ethylbenzene 41.1J Toluene 2260 m&p-xylene 148J VI 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GP-3A 4' 8' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 MW-3 4' Benzene <25.0 Ethylbenzene <25.0 Toluene <25.0 m&p-xylene <25.0 VII 4' 10' Benzene <25.0 <25.0 Ethylbenzene <25.0 <25.0 Toluene <25.0 <25.0 m&p-xylene <25.0 <25.0 GP-8 4' 10' Benzene 212 <25.0 Ethylbenzene 81.2 <25.0 Toluene 862 <25.0 m&p-xylene 267 <25.0

101 GPTW-16 4' 6.5' Benzo(a)pyrene 286 <3.8 GPTW-12 2' 7' Benzo(a)pyrene 21.4 <4.0 GPTW-11 5' Benzo(a)pyrene <3.7 GPTW-10 4' 6' Benzo(a)pyrene GPTW-13 6' Benzo(a)pyrene <3.7 GPTW-20 4' 11' Benzo(a)pyrene <3.9 <4.6 GPTW-6 4' 8' Benzo(a)pyrene < GPTW-8 4' 8' Benzo(a)pyrene <11.0 <4.4 GPTW-5 4' 8' Benzo(a)pyrene <4.2 <4.2 GPTW-9 6' Benzo(a)pyrene <3.8 GPTW-17 4' 13' Benzo(a)pyrene <3.8 <4.3 GPTW-7 4' 7' Benzo(a)pyrene 31.4 <7.5 GPTW-18 4' 12' Benzo(a)pyrene <4.2 <3.8 Designation A B C D E F G H I J K L M N O P Q R S T U V GPTW-19 4' 11' Benzo(a)pyrene <3.9 <4.0 Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST VIII 4' 8' Benzo(a)pyrene <4.4 <3.8 MW-3 4' Benzo(a)pyrene <3.8 V 2' 8' 11' Benzo(a)pyrene 13.1 <4.0 <4.0 GP-6 8' Benzo(a)pyrene 2720 VII 4' 10' Benzo(a)pyrene 10 <3.9 MW-1 4' Benzo(a)pyrene 286 GP-2 4' Benzo(a)pyrene 17.9 GP-1A 8' Benzo(a)pyrene 61.7 GP-3A 4' 8' Benzo(a)pyrene < MW-2 4' 8' Benzo(a)pyrene VI 4' 8' Benzo(a)pyrene GP-1A 8' Benzo(a)pyrene 61.7

102 GPTW-16 4' 6.5' Arsenic Lead GPTW-12 2' 7' Arsenic Lead MW-31 2' 10' 15' Arsenic Lead GPTW-14 4' Arsenic NA Lead 8.5 GPTW-10 4' 6' Arsenic 6.2J 2.3 Lead GPTW-11 5' Arsenic 1.7 Lead 2.1 GPTW-13 6' Arsenic 1.5 Lead 1.6 MW-32 4' 10' 16' Arsenic Lead GPTW-17 4' 13' Arsenic Lead GPTW-20 4' 11' Arsenic J Lead GPTW-9 6' Arsenic 1.7 Lead 2 GPTW-17 4' 13' Arsenic Lead GPTW-18 4' 12' Arsenic Lead GPTW-19 4' 11' Arsenic 3 2.0J Lead GPTW-6 4' 8' Arsenic Lead I 4' 10' Arsenic Lead III 4' 8' Arsenic Lead GPTW-3C 4' 9' Arsenic NA NA Lead GPTW-8 4' 8' Arsenic Lead GPTW-5 4' 8' Arsenic Lead II 4' 8' 10' Arsenic Lead MW-4 4' 8' Arsenic NA NA Lead IX 4' 8' 12' Arsenic Lead GP-8 4' 10' Arsenic NA NA Lead MW-33 4' 10' 16' Arsenic Lead GPTW-7 4' 7' Arsenic Lead IV 2-4' 8' 10' Arsenic Lead Designation A B C D E F G H I J K L M N O P Q R S T U V MW-34 4' 10' Arsenic Lead Name Former Municipal Incinerator SWMU 9 Satellite Accumulation Area SWMU 20 Sump Pump Basin SWMU 21 Media Blaster SWMU 9 Satellite Accumulation Area SWMU 2 Paint Solvent Waste UST Piping SWMU 3 & 4 Vapor Degreaser Unit/Drums SWMU 3 & 4 Vapor Degreaser Unit/Drums Former 1,500-Gallon TCE AST Former 550-Gallon Diesel Fuel AST 500-Gallon Diesel Fuel UST AIP 3,000-Gallon Gasoline UST AIP 5,500-Gallon Gasoline UST AIP 15,000-Gallon Fuel Oil UST AIP 8,000-Gallon Fuel Oil UST AIP 15,000-Gallon Fuel Oil UST AIP Former Waste Paint Solvent UST Former Waste Paint Solvent UST Former 1,000-Gallon Gasoline UST 15,000-Gallon Fuel Oil UST AIP 500-Gallon Fuel Oil UST AIP Former 2,000-Gallon Fuel Oil UST V 2' 8' 11' Arsenic Lead VIII 4' 8' Arsenic Lead GP-6 8' Arsenic 3.5 Lead 1660 MW-3 4' Arsenic 1.4 Lead 1.4 VII 4' 10' Arsenic Lead MW-1 4' Arsenic 3.4 Lead 29.8 GP-2 4' Arsenic 3.7 Lead 31.9 VI 4' 8' Arsenic Lead GP-1A 8' Arsenic 5.2 Lead 87.5 MW-2 4' 8' Arsenic Lead GP-3A 4' 8' Arsenic Lead MW-4 4' 8' Arsenic NA NA Lead

103 APPENDIX B USEPA SOIL CLEANUP STANDARDS

104 Waste and Cleanup Risk Assessment You are here: EPA Home OSWER Waste and Cleanup Risk Assessment Databases and Tools Soil Screening Guidance for Chemicals (SSG) SSG Home SSG Search Soil Screening Guidance for Chemicals Equation Values for Ingestion Noncarcinogenic Parameter Value Carcinogenic Age-adjusted Parameter Value Carcinogenic Nonadjusted Parameter Value Target Hazard Quotient (unitless) 0.2 Target Risk (unitless) 1.0E-7 Target Risk (unitless) 1.0E-6 Body Weight (kg) 15 Adult Body Weight (kg) 70 Body Weight (kg) 70 Child Body Weight (kg) 15 Exposure Duration (yr) 6 Adult Exposure Duration (yr) 24 Exposure Duration (yr) 25 Child Exposure Duration (yr) 6 Exposure Frequency (day/yr) 350 Exposure Frequency (day/yr) 350 Exposure Frequency (day/yr) 250 Intake Rate (mg/day) 200 Adult Intake Rate (mg/day) 100 Intake Rate (mg/day) 100 Child Intake Rate (mg/day) 200 Average Lifetime (yr) 70 Average Lifetime (yr) 70 Age-adjusted Ingestion Factor (mg-yr/kg-day) Soil Screening Levels for Ingestion (mg/kg) Analyte Cas Number Oral RfD Oral Slope Factor Noncarcinogenic Carcinogenic (Age-adjusted) Carcinogenic (Nonadjusted) Benzene E E-02 a 6.26E E E+01 Cumene E-01 a 1.56E+03 Dichlorobenzene, 1, E-02 a 1.41E+03 Dichlorobenzene, 1, E-02 b 2.66E E+02 Dichloroethylene, 1,2-cis E-02 b 1.56E+02 Ethylbenzene E-01 a 1.56E+03 Methylene Chloride E-02 a 7.50E-03 a 9.39E E E+02 Naphthalene E-02 a 3.13E+02 Tetrachloroethylene E-02 a 5.20E-02 v 1.56E E E+01 Toluene E-02 a 1.25E+03 Trichloroethane, 1,1, E-01 v 3.13E+03 Trichloroethylene E-04 v 4.00E-01 v 4.69E E E+00 Trimethylbenzene, 1,2, E E+02 Trimethylbenzene, 1,3, E E+02 Xylene, Mixture E-01 a 3.13E+03 Xylene, m E-01 b 3.13E+03 Xylene, o E+00 b 3.13E+04 Equation Values for Inhalation of Fugitive Dust