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Countryside Market, Stockton - 3 - 12 December 2023 potential future vapor intrusion risk. At least one of the soil gas wells should be located in the vicinity of the former dispenser island as it is the most likely source of shallow impact to soil at the Site. Additionally, please include shallow lithology in your evaluation of locations for soil gas wells, and attempt to target sandy soil where possible. You will need to submit a work plan and assessment report for this work. In the initial meeting, the JET had agreed that soil gas sampling would be completed following completion of SVE remediation. However, in the follow-up meeting, OSCF and Central Valley Water Board staff agreed that the existing SVE wells are sufficiently deep so as to not affect the collection of shallow soil gas samples while the system is operating. We also agreed that soil gas samples should be collected sooner rather than later so as to determine if there is a vapor intrusion risk and evaluate the potential need to expand the SVE system to address shallow soil gas impact. 8. Downgradient domestic supply well DW10967 has a well-head treatment system with granular activated carbon (GAC) filter media. In order to ensure clean drinking water for the residents of this property, the JET agreed that budget for one replacement of the GAC media is needed. 9. Existing Site SVE wells are screened 30-60 feet bgs and 60-80 feet bgs. In the event that the requested soil gas sampling indicates a significant vapor intrusion risk, the existing SVE wells are too deep to remediate hydrocarbon impact to shallow soil. As such, in the follow-up meeting OSCF and Central Valley Water Board staff agreed that the grant amendment should include contingency costs for the installation of up to three SVE wells to be installed as needed based on soil gas results. Associated work plan and summary report will be needed as well. 10.The JET agreed that the grant amendment should include contingency costs for the following case closure proceedings: a. Preparation and submittal of an evaluation of Site conditions against LTCP criteria. b. Preparation and mailing of a pre-closure public comment fact sheet. c. Destruction of all remaining Site monitoring and remediation wells. i. Well destructions in San Joaquin County should all be budgeted for over-drilling as San Joaquin County Environmental Health Department provides variances for pressure grout destruction only in limited cases. ii. Sufficient costs for city and county drilling permits or encroachment permits should be included. iii. Sufficient costs for communication with off-Site property owners to gain right-of-entry should be included as needed. d. Decommissioning of Site remediation equipment and the associated equipment enclosure compound.