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Artesian Environmental Consultants measured hydiocarbon thickness in MWA on March 16, 1992 to be 1 82 feet Groundwater flow driection on March 16, 1992 was to the southeast Water depth was measured on March 16, 1992 for MW-1 through MW-3 at 32 5, 32 7 and 32 4 feet below ground surface, respectively Artesian Environmental Consultants (Artesian) dulled three soil borings, B-1 through ' B-3, on the property on May 1, 1992 The soil borings B-1 through B-3 were drilled to depths of 45, 45 and 43 feet, respectively, below ground surface All three borings were drilled into native material All three borings, B-1 through B-3 were ' subsequently converted into monitor wells MW-4 through MW-6, respectively Shallow groundwater was encountered in all the wells at approximately 32 feet below ground surface IThe soils were logged by a project geologist under the supervision of a Califoinia- iegistered geologist Soil samples were collected at least every 5 feet for hthologir-, hydrologic and characterization and possible chemical analysis The soils were screened with a photoionization detector (PID), an insu ument to detect organic vapors Using a PID, organic vapor was not detected in the soil borings Soil Analysis Soil samples were below detection limits (ND) for total petroleum hydrocarbons as gasoline (TPH-g) and diesel (TPH-d) Borehole B-1 contained 7 7 ppb and 18 ppb toluene and xylene respectively, at a depth of approximately 6 0 - 6 5 feet BGS At approximately 110 - 116 feet BGS, B-1 indicated 8 1 ppb total xylenes Borehole B-2 had 7 3 ppb total xylenes at approximately 110 - 11 5 feet BGS All other values for B-2 were ND for all samples and analyses Borehole B-3 contained 5 7 ppb for benzene at approximately 6 0 - 6 5 feet BGS All other values for B-3 were ND for all samples and analyses IGroundwater Analysis Groundwater samples were below detection hmits (ND) for total petroleum I hydrocarbons as gasoline (TPH-g) and diesel (TPH-d) with the exception of the groundwater monitoring well water in MW-3 MW-3 contained 650 parts per billion (ppb) diesel, however, this value reflects the presence of long chain hydrocarbons, which were observed in the diesel range but do not have the characteristic diesel pattern Groundwater monitoring well MWA contained 1 2 ppb toluene All othet groundwater monitoring well samples were below detection hrruts for BTEX Groundwater Qradir„nt The monitor wells were surveyed relative to each other The static water level measured on April 15, 1992 ranged from 5 12 to 5 21 feet below ground surface The groundwater flow direction was to the west southwest at a gradient of 0 0025