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The Newark Group, Inc. - 5 - 27 February 2013 800 W. Church St., Stockton San Joaquin County d. Explain how use of shallow groundwater can be restricted, since such restrictions typically require a Basin Plan Amendment by the Regional Board. Provide a proposed plan for bringing the four out of service onsite supply wells back online per San Joaquin County regulations (the fifth well in the Dopaco area was reportedly an active fire protection well for the onsite paper recycling facility per discussions during my site inspection in May 2012), e. Provide a plan to mitigate soil vapor exposure to protect the human health of construction workers during redevelopment, and a tracking mechanism to notify regulators and interested parties if deed restrictions are developed, f. Provide additional information on the source for the chlorinated solvents detected in groundwater in Areas B-7, B-14, and B-15 and in the Dopaco area. The case fails the General Criteria for the State Water Resources Control Board Low Threat Closure Policy(LTCP) for the presence of chlorinated solvents. g. Provide a rationale why the Figure 4 Area B-15 shallow groundwater plume, which is <50' from McDougal Slough, is not a threat to a surface water body, or submit a work plan to continue the groundwater investigation of Area B-15 by 30 March 2013. The two non-detect grab groundwater samples were at least 50' north and 50' south of cross section line B-B', which is along the east-west axis of the groundwater plume shown on Figure 4. The case fails the Media-Specific Criteria: Groundwater for the LTCP for the plume distance to a surface water body. See i. below. h. Provide a risk assessment demonstrating the level of threat to human health for the TPHd and TPHg results at 4.5' bgs at B-33. The case fails to meet any of the site specific scenarios without soil vapor sampling of the Media- Specific Criteria: Petroleum Vapor Intrusion to Indoor Air for the LTCP and also fails the LTCP for levels of soil contamination (>100 mg/kg) with no bioattenuation zone. i. Free product was noted in the Report drilling logs for boring B-34 at the depths of 15' to 16.5' bgs and 20' to 21' bgs. Boring B-15, located 20' northeast of B-34, reported TPHd, 25,000 mg/kg at 15' bgs. The lateral extent of the free product in soil was not determined to the north and to the east of B-15 and B-34 towards McDougal Slough (50' east of B-15). This constitutes a data gap and additional investigation is necessary to evaluate whether free product will require removal to the most practical extent under the General Criteria for the State Water Resources Control Board Low Threat Closure Policy (LTCP). Submit a work plan to determine the vertical and