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r KEI-P92-0205 .QR2 July 13 , 1993 Page 2 the wells were checked for depth to water and the presence of free product. Prior to sampling, the wells were also checked for the presence of a sheen. No free product or sheen was noted in any of the wells during the quarter The monitoring data collected this quarter are summarized in Table 1. Water samples were collected from all of the wells on May 28 , 1993 . Prior to sampling, the wells were each purged of between 5 and 8 gallons of water by the use of a surface pump. During purging operations, the field parameters pH, temperature, and electrical conductivity were recorded and are presented in Table 2 . Once the field parameters were observed to stabilize and a minimum of four casing volumes had been removed from each well, samples were collected by the use of a clean Teflon bailer. The samples were decanted into clean VOA vials and/or one-liter amber bottles, as appropriate, which were then sealed with Teflon-lined screw caps and stored in a cooler, on ice, until delivery to a state-certified laboratory ` HYDROLOGY • The measured depth to ground water at the site on May 28 , 1993 , ranged between 8 . 84 and 10. 36 feet below grade. The water levels in all of the wells have shown net decreases ranging from 0 . 86 to 2 . 85 feet since February 27, 1993 Based on the water level data gathered during the quarter, the ground water flow direction appeared to be complex, as shown on the attached Potentiometric Surface Maps, Figures 1, 2 , and 3 . The average hydraulic gradient at the majority of the site on May 28 , 1993, was approximately 0 . 001. ANALYTICAL RESULTS The ground water samples collected this quarter were analyzed at Sequoia Analytical Laboratory and were accompanied by properly executed Chain of Custody documentation. The samples were analyzed for total petroleum hydrocarbons (TPH) as gasoline by EPA method 5030/modified 8015, benzene, toluene, ethylbenzene, and xylenes by EPA method 8020, and TPH as diesel by EPA method 3510/modified 8015 . The analytical results of all of the ground water samples collected from the monitoring wells by KEI to date are summarized in Table 3 . The concentrations of TPH as gasoline, benzene, and TPH as diesel detected in the ground water samples collected this quarter are • shown on the attached Figure 4 . Copies of the laboratory analyti- cal results and the Chain of Custody documentation are attached to this report.