Proposed Cleanup Plan KFF Site, Sherwood Oregon

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1 DEQ Northwest Region Cleanup Program Proposed Cleanup Plan KFF Site, Sherwood Oregon Mark Pugh, Project Manager DEQ Northwest Region Cleanup Program Sept. 22, 2016 Sherwood, Oregon Mark Pugh, RG Oregon Department of Environmental Quality

2 Presentation Outline Background Information Site History Previous Investigations Remedial Action Areas Cleanup Options Proposed Plan Question and Answer Session

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4 Site History Historical farm land covering approximately 40 acres Rolling topography with generally thin soil layer and shallow basalt bedrock Tannery waste placed on the ground surface between ; lime added to control odor; tilled into soil Tannery waste contains primarily trivalent chromium (CrIII), with relatively low concentrations of hexavalent chromium (CrVI) Farm land initially subdivided into 10 parcels and developed in the late 70s- mid-80s ; additional subdivision for single family residential use Approximately 2 acre wetland area

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7 Previous Investigations DEQ (2005) Preliminary Assessment EPA (2006) Integrated Assessment Total Chromium (primarily CrIII) detected across the site CrVI not identified as a concern Referred to DEQ for additional followup DEQ (2007) DEQ Risk Assessment 2011-Change in CrVI cleanup level (130X lower)

8 Settlement 2010 DEQ begins settlement negotiations with responsible parties May 2011 Global settlement - $2,600,000 cash payment from parties in exchange for liability release from DEQ December 2013 Court Issues final decision Total settlement $2.6 million $2.3 million available for cleanup

9 DEQ Remedial Investigation-2013 Potential Human Health Risk from CrVI in soil on most tax lots Potential Ecological Risk to birds and benthic organisms from CrIII in soil/sediment

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13 Remedial Action Objectives RAO# 1. Prevent current residents from exposure to upland soils containing Cr(VI) resulting greater than1 in 1,000,000 cancer risk RAO#2. Prevent future residents from exposure to upland soils containing Cr(VI) resulting greater than1 in 1,000,000 risk RAO#3. Reduce transport of chromium, lead, and mercury in upland surface soil to wetlands that would result in further sediment contamination

14 Cleanup Options Capping Removal Treatment Institutional Controls Presence of Contamination Maintain Protective Remedy -----Easement and Equitable Servitudes -----Deed Notice -----Other measures selected or approved by the Director

15 KFF Cleanup Alternatives Capping in Place Comprehensive Capping in Place On-Site Consolidation and Capping Excavation and Off-Site Disposal

16 Capping in Place Cost Effective Relatively easy to implement Leaves exposed contamination susceptible to contact by residents, and storm runoff Concerns of compromising cap and redistributing contamination during site development DEQ would likely require confirmation testing

17 Comprehensive Capping in Place Highly effective Reduces potential for mobilization of residual contamination No confirmation testing needed High Cost* Larger Cap Area to Maintain

18 On-Site Consolidation and Capping Highly effective Coordinated with grading plan Reduce cap maintenance area Reduces potential for mobilization of residual contamination High Cost*

19 Excavation and Off-site Disposal Reduces contaminant mass Reliable No cap maintenance Bedrock prevents complete removal May require imported fill for grading Implementation risk (truck traffic;dust) Leaves exposed contamination susceptible to contact by residents and storm runoff

20 Proposed Cleanup Plan Current Use (DEQ) -Yard Areas -Tax Lots 100,200,700,1200 Future Use (Owners/developers) -Undeveloped Properties/Areas

21 Proposed Cleanup Plan for Current Use Capping Preferred-Cost Effective $700,000 estimated cost Consolidation and capping and/or excavation and off-site disposal Maintenance/Public Communication ECSI on-line database Ongoing Coordination with City of Sherwood Real Estate Disclosure Laws DEQ Periodic Inspection NFA/Certificate of Completion recorded on deed* Off-Site Properties to south *Not in Staff Report

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26 Proposed Cleanup Plan for Future Use Owner/developer implement cleanup Comprehensive capping preferred Cleanup costs defrayed through apportionment of settlement funds based on area cleaned up Apportionment amount based on relative tax lot size

27 Proposed Cleanup Plan for Future Use (cont d) $1,400,000 available for apportionment Apportionment Agreement Flexibility in cleanup method Maintenance/Public Communication ECSI on-line database Ongoing Coordination with City of Sherwood Real Estate Disclosure Laws (NFA letter) DEQ Periodic Inspection *Not in Staff Report

28 DEQ Roles and Responsibilities Preparation of agreements and other administrative documents Oversight and technical assistance Conduct public notice and comment Provide cap specifications for incorporation into property-specific plans

29 DEQ Roles and Responsibilities (cont d) Soil Management Plan Cap Inspection Identification and Testing of Cap Material* *Not in Staff Report

30 Next Steps DEQ accept comments through September 2016 Review and respond to comments as appropriate Prepare Record of Decision with selected remedy- October 2016 Agreements with individual owners/developers (ongoing) Planning and work plan preparation fall 2016-winter 2017 DEQ implement remedy on current use property in summer 2017

31 Mark Pugh DEQ Northwest Region Office 700 NE Multnomah Street Suite 600 Portland, OR (503)