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KEI-P91-0202 .4 R2 . August 10, 1992 Page 2 during the quarter. The monitoring data collected this quarter are summarized in Table 1. Water samples were collected from the wells on July 13 , 1992 . Prior to sampling, the wells were each purged of between 2 and 9 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 approximately four casing volumes had been removed from each well (except MW5, which de-watered after 2 gallons were purged) , samples were then collected by the use of a clean Teflon bailer. The samples were decanted into clean VOA vials that were then sealed with Teflon-lined screw caps and stored in a cooler, on ice, until delivery to the state-certified laboratory. HYDROLOGY The measured depth to ground water at the site on July 13 , 1992 , ranged between 61. 60 and 73 . 64 feet below grade. The water levels in all of the wells have shown net decreases ranging from 2 . 14 to 2 . 57 feet since April 7 , 1992 , except for well 14W5, in which a net decrease of 0. 06 feet was observed. Based on the water level data gathered on July 13 , 1992, the ground water flow direction appeared to be to the southeast, as shown on the attached Potentiometric Surface Map, Figure 1 . The ground water flow direction on June 10 and May 8 , 1992 , appeared to be toward the southwest, as shown on the attached Potentiometric Surface Maps, Figures 2 and 3 . The southwesterly flow direction is similar to the flow direction reported in the previous two quarters. The average hydraulic gradient across the site on July 13 , 1992 , was approximately 0. 0029 . ANALYTICAL RESULTS The ground water samples 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/modi- fied 8015, and benzene, toluene, xylenes, and ethylbenzene (BTX&E) by EPA method 8020. The ground water sample analytical results are summarized in Table 3 . The concentrations of TPH as gasoline and benzene detected in the ground water samples collected this quarter are shown on the attached Figure 4 . Copies of the laboratory analytical results and Chain of Custody documentation are attached to this report.