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Geosynteco consultants 1. INTRODUCTION On behalf of the Lincoln Center Environmental Remediation Trust(Trust),Geosyntec Consultants, Inc. (Geosyntec) has prepared this Work Plan to address residual soil vapor and groundwater impacts underlying the northern parking lot at the Lincoln Village Shopping Center in Stockton, California (the Site; Figure 1). The area in the northern parking lot being addressed was remediated and closed during previous efforts at the Site. The residual soil and groundwater impacts being addressed as part of this Work Plan are localized and the mass remaining is expected to be finite in nature. Remediation at the Site is being conducted as part of the Site Response Plan defined in the "Amended First Final Order, Final Judgement and Order Terminating Permanent Injunction" (Consent Decree) and supporting Declaration dated May 15, 2001. By definition, the Site Response Plan is a collective group of work plans and remedial action plans that describe the investigation and the clean-up to be undertaken at the Site. Site work, including preparation of this document, is completed with oversight from the Central Valley Regional Water Quality Control Board (CVRWQCB). 1.1 Work Plan Objectives and Regulatory Framework This Work Plan has been prepared in response to a request from the CVRWQCB to assess options for remediating residual shallow soil vapor impacts resulting from former dry-cleaning operations in the vicinity of the northern parking lot at the Site and to evaluate reasonable remedial action to mitigate residual groundwater impacts reported in monitoring wells MW-007A and MW-009A (CVRWQCB, 2021; Figure 2). The CVRWQCB also requested that the post-remediation soil vapor concentrations in the northern parking lot meet the previous soil vapor clean-up goal of 603 micrograms per cubic meter(µg/m3) (the Commercial California Human Health Screening Level [CHHSL] for PCE in soil vapor. This Work Plan describes the rationale for selecting soil vapor extraction (SVE) to address residual soil vapor impacts in the northern parking lot and the methodology for planning and field implementation of SVE activities. In addition,this Work Plan summarizes the rationale and methodology for focused in-situ chemical oxidation (ISCO) injections as an option to address persistent low-level groundwater impacts reported in MW-007A and MW-009A, if deemed necessary. The Trust is currently permitted to inject potassium permanganate (KMn04) under General Waste Discharge Order No. 85-2015- 0149 for In-Situ Groundwater Remediation (WDR permit). As such, the scope of work identified herein falls under the aforementioned permit. Northern Parking Lot Remedial Plan 1 August 6,2021