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an immiscible layer on PT-MW3 but groundwater samples were not collected for analysis. GAS <br /> also reported that groundwater surface elevations had dropped approximately five feet since <br /> 1988 (Geological Audit Services, 1991) and that the groundwater surface elevation map had a <br /> relatively flat gradient with a slight slope to the south. <br /> GAS (1991) concluded the following: (1)that offsite migration of petroleum hydrocarbons <br /> released from the Parmar Texaco site was a possibility; (2)the lateral extent of soil and/or <br /> groundwater petroleum hydrocarbon contamination was not yet determined; (3)the water <br /> bearing sand at approximately 40 feet bgs should allow recovery of the free product and/or <br /> dissolved contamination from the first water-bearing zone; (4)that a more northerly source may <br /> be contributing to the identified petroleum hydrocarbon groundwater contamination and; (5)that <br /> 3,000 to 4,000 gallons of gasoline were potentially present and contained in the groundwater <br /> beneath the site. <br /> Based on the conclusions reached by GAS (1991) a limited groundwater extraction from <br /> monitoring wells PT-MW2 and MW3 was undertaken by Falcon Energy during 1992. Falcon <br /> Energy reportedly extracted and removed several thousand gallons of petroleum hydrocarbon <br /> impacted groundwater(Dana Booth,verbal communication, 2003). The disposition of these <br /> removed liquids is unknown. No information regarding the volume and ultimate disposition of <br /> these fluids. <br /> In January 1994, PHSEHD directed that the three monitoring wells to be sampled to assess <br /> current groundwater conditions beneath the site. Mr. Dana Booth, Consulting Geologist was <br /> retained by Mrs. Yearing to conduct the work.Mr. Booth supervised the resurveying and <br /> redevelopment of the three monitoring wells, and water sample collection of each of the three <br /> existing monitoring wells. On March 7, 1994 the following groundwater conditions were <br /> reported by Booth (1994)to exist at the site: <br /> (1) A product layer of 0.03 foot thickness was measured at PT-MW3; <br /> (2) The water samples from PT-MW 1 and PT-MW2 reportedly contained TPH-g and BTEX <br /> concentrations significantly above established Maximum Contaminant Levels (MCL's); <br /> (3) The groundwater gradient was calculated at 0.003 toward the southwest(using a 0.8 <br /> relative density for the product layer). <br /> Two water samples (PT-MW 1 and PT-MW2)were reportedly collected and transported to West <br /> Laboratories, Davis, California under chain of custody documentation. The water samples were <br /> analyzed using USEPA Test Method 602 for benzene,toluene, ethylbenzene. and xylene and <br /> 8015M for TPH-gasoline. Analytical reports for these two water samples were reported to <br /> contain maximum concentrations as follow: TPH-gas (23,000 µg/1); benzene (2,000 µg/1); <br /> toluene (3,500 µg/l); ethylbenzene (2,800 µg/1); and xylene (2,800 µg/1). No water sample was <br /> collected from monitoring well PT-MW3. <br /> The onsite soil stockpile from the UST removal was reportedly sampled by Dana Booth on <br /> February 7, 1994. Six soil samples were reportedly collected from the stockpile using a modified <br /> Parmar\Site Assessment Workplan\02152018.wpd 5 <br />