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KEI-P88-1013 .QR6 November 10, 1993 Page 2 collected by KEI this quarter for the Unocal wells are summarized in Table 1. Water samples were collected by KEI from all of the Unocal wells (except MW6) on September 29 , 1993 . Prior to sampling, the wells were each purged of between 7 . 5 and 10 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 3 . Once the field parameters were observed to stabilize and a minimum of 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, labeled, and stored in a cooler, on ice, until delivery to a state-certified labora- tory. On September 29 , 1993 , a point monitoring and sampling event was also conducted with the nearby Montgomery Ward site (the site of a former gasoline dispensing facility) . Monitoring data from the Montgomery Ward site are summarized in Table 2 . HYDROLOGY The measured depth to ground water at the former Unocal site on September 29 , 1993 , ranged between 58 . 30 and 59 . 11 feet. The water levels in all of the wells have shown net decreases ranging from 1. 38 to 1 . 64 feet since June 28 , 1993 . Based on the water level data gathered during the quarter (includ- ing the point monitoring event conducted on September 29 , 1993) , the ground water flow direction over the majority of the site vicinity was to the south, as shown on the attached Potentiometric Surface Maps, Figures 1, 2 , and 3 . The ground water flow direction at the Unocal site has varied from the southwest to the east- northeast since July of 1992 . The average hydraulic gradient over the majority of the site vicinity on September 29 , 1993 , was approximately 0 . 008 . ANALYTICAL RESULTS The ground water samples collected from the existing Unocal monitoring wells 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/mode-- fled 8015 , for benzene, toluene, ethylbenzene, and xylenes by EPA method 8020, and for EPA method 8010 constituents.