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Third Quarter 1995 Mondonng and Sampling-Report 2 . The Southland Corporation,9110 Thoroton Road Stockton CA August 10 1995 Based on monitoring data collected from the site-related wells,groundwater flow diverges from the site to the northeast and southwest at a gradient of 0 002 ftt t No SP was found in any of the monitoring wells Groundwater levels increased approximately 3 2 feet since the previous quarterly monitoring event(January 26, 1994) Historical and recent groundwater monitoring data are summarized in Table 1 (Attachment 2) Field Data sheets are included in Attachment 3 Monitoring Well Sampling and Analytical Results On June 6, 1995,the following monitoring wells were sampled MW-1 through MW-5,MW-8 through MW-10, MW-13, MW-15 (A, B, & C), MW-16, MWA 7B and MW-17C, MWA 8 through MW-20, former pumping wells PW-1 through PW-3,and former recovery well RW-1 Monitoring wells MW-11, MW-12, and MW-14 will be sampled during the next quarterly monitoring and sampling event in September 1995 At least three well volumes of water was purged (unless the wells were purged dry)to ensure stabilization of pH, conductivity and temperature The wells were allowed to recharge to at least 80 percent of the initial level before sampling Samples were collected from the monitoring wells using disposable batters The samples were labeled, stored on ice in an insulated container, and delivered to GTEL Environmental Laboratories in Concord, California under chain-of-custody manifest The samples were analyzed for BTEX and TPH-G by Environmental Protection Agency (EPA) methods 8020/modified 8015 . Purge water was contained in a Department of Transportation (DOT)-approved 55-gallon drums and stored in the fenced compound on site pending characterization and disposal On June 6, 1995, approximately 150 gallons of purge water was pumped to the sanitary sewer in accordance with the Special Permit for Waste Water Discharge letter, dated June 5, 1995, from the City of Stockton, Department of Municipal Utilities Analytical results for groundwater samples collected on June 6, 1995 are summarized in Table 1 No ,TPH-G was detected in any of the monitoring wells sampled Benzene was detected only in groundwater from wells MWA and MW-4 at 1 7 parts per billion and (ppb) and 0 8 ppb, respectively A copy of the laboratory analytical report and the chain-of-custody manifest are included in Attachment 4 The site is currently under consideration for closure of environmental remedial activities through the Regional Water Quality Control Board, Central Valley Region (RWQCB-CVR) and the San Joaquin County Public Health Services (SJCPHS) During a Technical Review Committee (TRC) meeting held on May 18, 1995, the request for site closure was discussed In a letter to Southland summarizing the meeting,dated June 22, 1995, the SJCPHS reiterated the request that in addition to sampling the site-related monitoring wells, all formerly sampled domestic wells (19 wells) located in the vicinity of the site be sampled and the results submitted to the SJCPHS for evaluation On July 31, 1995, groundwater samples were collected from eight domestic wells in the vicinity of the site and submitted for analysts of BTEX and TPH-G The sampling of the domestic wells was observed by SJCPHS I',91 GROUNDWATER �` 'TECHNOLOGY