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i 1 ' 1444 MARIPOSA ROAD WKA No 2938 06 September 6, 2000 ' Page 8 MW6 and MW7 were wells drilled along the northeast corner and east side of the property, ' respectively Soils encountered beneath the site during drilling activities consists primarily of silty clay, clayey sand, sandy clay, and fine to medium sand The sands were encountered in the soil borings at depths ranging from approximately 50 to 70 feet bsg Geologic cross-sections of subsurface soil in the vicinity of the former UST excavation are presented on Plates 6 and 7 Soil logs of the borings are presented on Plate Nos 8 through 15 A total of eleven soil samples were obtained from the borings at depths ranging from 47 to ' 95 feet bsg The soil samples were placed in an ice chest containing ice,and submitted under chain-of-custody to a California-certified laboratory for chemical analysis of TPH as gasoline ' and oxygenates Soil borings MW4 through MW7 were converted into monitoring wells (MW4 through MW7) The wells were constructed using two-inch diameter, flush pointed, Schedule 40 PVC casing, 0 02- inch slotted casing was used for the screened interval Well construction details are also shown on ' Plates Nos 8 through 15 ' Water samples were obtained from the wells through the pump and tygon tubing and decanted into appropriate sample containers provided by the laboratory The water samples were ' immediately placed in an ice chest containing ice and submitted with chain-of-custody documentation to a California-certified laboratory for chemical analysis of TPH as gasolme and ' oxygenates Laboratory analysis of eight soil samples obtained from borings MW4 through MW7 revealed no ' detectable concentrations of petroleum hydrocarbons or oxygenates in soil Trace concentrations of benzene(0 0074 mg/kg) and MTBE (0 011 mg/kg), however, were reported in soils sample B5- 91 obtained from boring B5 at a depth of 82 feet Additional samples obtained from boring B5 at depths of 90 and 95 feet revealed no detectable concentrations of the above analyses ' WALLACE KUHL Pecvcled paper &ASSOCIATES INC