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v Upon obtaining the above described information, we promptly initiated remediation efforts directed toward the handling of the contaminated soil excavated during the tank removal operation. With the permission of San Joaquin PHS/EHD and the San Joaquin County Air Pollution Control District this soil was aerated on site until 1-12-89, when testing indicated that no further contamination was present in the soil (see Exhibit C) . On July 7 , 1988 we invited further investigation of the site by Applied Geosytems of Sacramento resulting in two soil borings, B-1 & B-2 (see Exhibit D for area and site maps ) . B-1 was drilled to 30 feet and field screening with an OVA did not indicate contamination at that depth. A bottom sample was taken at 30 feet, however the analytical detection limits were too high for BTXE to confirm that no contamination was present. B-2 was drilled to 75 feet and field screening with an OVA indicated that contamination was present beginning at 30 feet, highest at 45 feet and ending at 75 feet. Two samples were collected in B-2 at 45 feet and 60 feet using a California-modified split spoon sampler equipped with clean brass sleeves. The samples were analyzed and contamination was noted at 45 feet (TPH 3 . 4 ppm, ehtylbenzene 100 ppb, toluene 1000 ppb, and xylene 500 ppb) and at 60 feet (xylene 900 ppb) . B-2 was converted into a monitoring well, MW-1, which in 1988 had a static water level of 63 . 59 feet. The Preliminary Report #38033-1, dated 8-5-88 , indicated groundwater contamination (TPH 4. 92 ppm, benzene 270 ppb, toluene 49 ppb, xylene 230 ppb, and ehtylbenzene 5 ppb) (see Exhibit E) . Soil statigraphy developed from the soil investigation found predominantly silty sands (SM) from the surface to a depth of 50 feet when the soil from 50 feet to 66 feet was a mixture of silt and sand (ML) returning to silty sand to the total depth of 80. 5 feet. See Exhibit F for a more detailed presentation of the soil statigraphy. In November, 1991 in response to a verbal request from Mary Meays, EHS of the San Joaquin PHS/EHD samplings of both the adjacent domestic well , approximately 250 feet from the subject site, and MW-1 were attempted. Test results from the sample of the domestic well indicated that no contamination was present. A copy of these test results from FGL Environmental were submitted to San Joaquin PHS/EHD at that time. On 1-13-92 Geological Audit Services, Inc. met Mary Meays, EHS on site and discovered that the MW-1 was dry at an approximate depth of 82 feet.