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V � KEI-P91-0202 .QR3 November 6, 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 October 12, 1992 Prior to sampling, the wells were each purged of between 2 . 5 and 6 .5 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, 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 a state-certified laboratory. HYDROLOGY The measured depth to ground water' in all of the wells at the site on October 12 , 1992 , ranged between 75 . 08 and 76 . 37 feet below grade, except for well MW5 , in which the depth to ground water was measured at 61. 47 feet below grade. Similar to previous quarters, the ground water elevation in well MW5 is significantly higher (approximately 15 feet) than all other wells. This occurrence is considered to be a localized (perched?) condition, and the data from well MW5 was not used in calculating ground water contours The water levels in all of the wells have shown net decreases ranging from 2 . 58 to 2. 77 feet since July 13 , 1992 , except for well MW5, in which a net increase of 0. 13 feet was observed. Based on the water level data gathered during the quarter, the ground water flow direction appeared to be predominantly to the south (varying from south to south--southeast)' , as shown on the attached Potentiometric Surface Maps, Figures 1, 2 , and 3 . The flow direction reported this quarter is similar to the predominant south and southwesterly flow directions reported in the previous three quarters. The average hydraulic gradient across the site on October 12 , 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. In addition, the ground water samples collected from monitoring wells MW1 , MW7 , MW8 , and MW9 were analyzed for fecal coliform by the membrane filter method.