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I I P3-6 a concentrations as hi as ( ). BTEX compounds were detected m the same three samples at c high 93 mg/kg(total xylene,P 1-6),the maximum benzene concentration detected was 2.8 mg/kg(PI-6). Table 1 summarizes the soil samples collected from the probe borings the site. TPH-g was detected in grab water samples at concentrations as high as 210,000 mg/l. BTEX compounds were also detected in four of five grab ground water samples at concentrations as high as 35,000 mg/1 (toluene P6), the maximum benzene concentration detected was 12,000 mg/l (P6). ' Analytical results of grab water samples are summarized on Table 2. The installation of the soil probe borings was summarized in the PIER prepared by AGE, dated 10 September 1996. Between July 1996 and April 1998 a total of six wells were installed on the sitc or on surrounding I properties in order to determine the lateral and vertical limits of the dissolved hydrocarbon plume. ' In July 1996, four soil borings were drilled and completed as 2-inch diameter ground water monitoring wells with slotted screen from approximately 5 to 25 feet bsg. In April 1997, soil borings B5 (MW-5)and B6(MW-6)were drilled and completed as ground water ' monitoring wells. Monitoring well MW-5 was completed using 2-inch diameter PVC casing with a slotted screen from approximately 3 to 10 feet bsg.Ground water monitoring well MW-6 was dual- completed with screen intervals installed from a depth of 20 to 23 feet bsg and 3 to 13 feet bsg. The installation of the first four monitoring wells was summarized in the PIER prepared by AGE, dated 10 September 1996. On 07 May 1998, soil borings B13 through B15 were advanced manually and one boring was completed as a ground water monitoring well.Borings B13,B 14(MW-7) and B15 were established I on the property at 52 West Beverly Place. The installation of the borings was performed using a six-inch diameter hand auger. A total of 15 soil borings have been advanced on and off the site, seven of which have been I completed as ground water monitoring wells,providing data concerning hydrocarbon impact on soil and ground water, soil composition, and ground water flow direction. Laboratory analysis of soil ' samples collected from monitoring wells and soil probe borings constrain the plume of impacted soil to the immediate vicinity of the former UST excavation.The lateral extent of impacted ground water appears to be delineated northeast, cast, south, west and northwest of the former UST excavation. ' Laboratory analysis of ground water samples collected north of the former UST excavation, from well MW4,have consistently detected total petroleum hydrocarbons quantified as gasoline(TPH-g), benzene, toluene, ethylbenzene and total xylenes (BTEX) and have generally detected the sample ' analytes in samples from MW-1. I - I Advanced GeoEnvironmental,Inc.