Laserfiche WebLink
GRANITE CONSTRUCTION —FRENCH CAMP Page 4 <br /> WKA No 2088 09 <br /> ' October 10, 2005 <br /> obtained beneath the former fuel dispenser TPH as gasoline (ranging from 1 0 to 54 mg/kg), <br /> diesel (ranging from 90 to 410 mg/kg) and motor oil (ranging from 82 to 130 mg/kg) were <br /> ' reported in the soil samples obtained from the soil stockpile <br /> 1 In March of 1993 soil borings B 1 through B 17 were drilled in the vicinity of the former USTs <br /> and dispenser islands Soil bonngs B 1 and B2 were constructed at approximate 30° angles from <br /> 1 vertical beneath the former 2,000-gallon waste oil tank located adjacent to the easterly side of the <br /> shop building The remaining borings were dnlled in the vicinity of the former USTs and <br /> dispenser island The borings ranged in depth from 16 to 26 feet bgs The subsurface soil <br /> consists primarily of sandy silts interbedded with silty clays and fine to medium grained sands <br /> A total of 40 soil samples were analyzed for petroleum hydrocarbons Results of laboratory <br /> analysis of soil samples collected from the angle borings did not reveal elevated concentrations <br /> of petroleum hydrocarbons or waste oil metals TPH as gasoline (2,000 mg/kg) and diesel (7,800 <br /> mg/kg) were detected at a depth of approximately 6 5 feet bgs beneath the former dispenser <br /> island Subsurface soils in the vicinity of the former USTs revealed TPH as gasoline (0 63 to 930 <br /> mg/kg) at depths ranging from 16 to 26 5 feet bgs <br /> On March 10 and 11, 1993 three two-inch diameter groundwater monitoring wells (MW1 <br /> ' through MW3) were constructed to total depths of 39 to 40 feet bgs in the vicinity of the former <br /> USTs and dispenser islands The wells were screened with 0 02-inch slotted Schedule 40 PVC <br /> casing from 20 to 40 feet bgs A licensed California surveyor surveyed the location and casing <br /> elevation of the wells <br /> ' On March 26, 1993 water samples were obtained from the wells The average depth to <br /> groundwater was approximately 25 feet bgs TPH as gasoline or BTEX were not reported in <br /> groundwater samples obtained from the monitoring wells MW 1 or MW2 However, TPH as <br /> ' gasoline at a concentration of 1,100 micrograms per liter(µg/1) was reported in the groundwater <br /> sample obtained from monitoring well MW3 TPH as diesel was not detected in the water <br /> samples obtained from the wells <br /> `dW <br /> WALLACE KUHL <br /> Recycied paper &ASSOCIATES INC <br />