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KEI-P89-1104 .R9 December 17 , 1992 Page 5 as diesel, TOG, and all EPA method 8010 compounds were non- detectable in all soil samples, except for sample MW1 at 10 feet, which showed 76 ppm of TOG. Analytical results of the ground water samples collected from monitoring wells MW1, MW2 , and MW4 indicated non-detectable levels of TPH as gasoline and BTX&E. In well MW3 , TPH as gasoline and benzene were detected at levels of 220 ppb and 7 . 6 ppb, respec- tively In well MW1 , TPH as diesel was detected at a level of 170 ppb, TOG was non-detectable, and all EPA method 8010 constituents were non-detectable, except for chlorobenzene and 1 , 2--dichloro- benzene at concentrations of 2 . 3 ppb and 7 . 4 ppb, respectively. The results of the soil analyses are summarized an Table 6 , and results of the water analyses are summarized an Tables 4 and 5 . Based on the analytical results, KEI recommended the implementation of a monthly monitoring and quarterly sampling program for all of the monitoring wells . Documentation of the well installation protocol , sample collection techniques, and sample results are presented in KEI ' s report (KEI-P89-1104 .R7) dated December 10 , 1990 . Based on the analytical results of the ground water samples collected through December 30 , 1991, no evidence of free product or sheen in any of the wells to that date, and a consistent ground water flow direction at the site, KEI recommended a modification to the existing monitoring and sampling program of the existing monitoring wells . Concentrations of TPH as gasoline and benzene in the water samples collected from all wells had been non-detectable for at least four quarters (one hydrological cycle) , i e. , since March of 1991 . In addition, TPH as diesel had been non-detectable in well MW1 for two quarters (since September of 1991) . Therefore, KEI recommended reducing the frequency of monitoring of the wells from monthly to quarterly; KEI also recommended reducing the frequency of sampling of the wells from quarterly to semi-annually. Destruction of the abandoned water well was completed on January 24 , 1992 , per KEI ' s work plan/proposal (KEI-P89-1104 . P4) dated July 19, 1990 . RECENT FIELD ACTIVITIES - WELL DESTRUCTION KEI conducted field work at the sub3ect site on July 15 , 1992 , when sludge, liquids and leach lanes were removed from a septic tank system located in the southwestern corner of the site. On October 20 to 26 , 1992 , the concrete septic tank was destroyed and was S removed an con3unction with the leach field. This work was performed in accordance with an agreement between Unocal and the