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and collection of soil samples Excavation procedures are scheduled to commence immediately . following the removal of three steel-underground storage tanks (USTs) at the site ' Soil will be excavated using a backhoe or an excavator Soil will excavated to a depth of one to two feet below the current depth of the UST inverts Soil will be placed into an excavation soil bin for ' transportation to an appropriate landfill class I landfill at Waste Management at Kettleman Hills or class II landfill at Forward Landfill at Stockton Excavated soil will be field screened for the presence of volatile organic compounds using an OVM,however, due to the release of waste fluids ' all waste placed into the bins will be disposed at an appropriate landfill Following t he e xcavation and s ampling c lean a nd appropriate b ackfill w ill b e p laced i nto t he ' excavation ' PREVIOUS SITE INVESTIGATION ' On 23 and 24 October 2001,four soil probe borings(BI through B4)were advanced at the site under EHD oversight Probe bonngs were advanced in former UST excavation and west, southwest and east of the former UST area to collect soil and grab water samples Probe boring B 1 was advanced to a total depth of 65 feet below surface grade (bsg) and borings B2 through B4 were advanced to 40 feet bsg Analytical data is presented on the attached tables Locations of the soil probe borings are illustrated on Figure 2 lieThe most intensely hydrocarbon-impacted soil was encountered in the area of the former USTs (boring B 1), contaminants were not detected in analyzed soil samples collected from borings B2 through B4 At boring location B 1,petroleum hydrocarbons were detected in collected soil samples to depths of 30 feet bsg,but generally was not detected in soil samples from 40 feet bsg and below The highest hydrocarbon concentrations were encountered at depths between 10 and 20 feet bsg ' Hydrocarbon-impacted ground water was encountered in all four soil borings The highes# concentration ofdissolved hydrocarbons quantified as TPH-g,TPH-d and overall BTEX compounds ' were present in a water sample collected at 40 feet bsg from boring B1, at the former UST area However,dissolved TPH-g and BTEX concentrations decreased radially northwest, southwest and east away from the area of the UST release In addition,dissolved TPH and BTEX were detected at ' low concentrations in a grab ground water sample collected from 60 feet bsg at boring B1 ' GROUND WATER MONITORING WELL INSTALLATION ' On 13 and 14 August 2002, five ground water monitoring wells were installed near the UST area (MW-1 though MW-5)to quantify the hydrocarbon concentration in ground water and determine the direction o f ground w ater flow F field w ork w as p reformed a s d escnbed i n t he A GE-prepared ' Monitoring Well Installation Work Plan,dated 08 July 2002, as amended and approved by the San Joaquin Country Environmental Health Department (EHD)by letter dated 18 July 2002