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SITE CONDITIONS FOR PHASE 2 INVESTIGATION About 2/3 of the site area is covered with buildings The area directly to the east of the solvent tank is the main portion of the building used by Vogue Cleaners The building fronts directly on the west side of the sidewalk, without room for drilling equipment The area to the south of the solvent tank is occupied by a building owned by others The driveway on the north side of the building is the only area accessible to drill equipment(MW #2 ) This driveway lies northeast of the solvent tank excavation Hydraulic gradient information provided by the San Joaquin Flood Control District shows that the typical hydraulic gradient in that area slopes to the northeast The area due east of the solvent tank has access only on the sidewalk or the south bound paved portion of California Street CITY PERMIT RESTRICTIONS The City of Stockton would not allow a soil boring in the paved portion of California Street A permit was issued for placing a Soil Bore in the sidewalk due east of the Tank#1 (solvent) Numerous utilities are located underground in this sidewalk area While drilling and working in the City Right of Way, traffic was to be under City traffic control measures PHS/EI-ID DRILLING PERMITS The PHS/EHD required the issuance and payment of two drilling permits An onsite drilling permit was issued for MW#3 and MW#4 An offsite drilling permit was issued for MW#2 located in the City owned sidewalk area • SOIL BORING & SAMPLING METHODS The soil boring for MW#4 was begun on 5/27/98 and completed the same day by Spectrum Exploration Soil samples were extracted with a split spoon sampler using BX brass sample tubes Each sample tube end was covered with Teflon sheet, capped with a plastic cap, and sealed with masking tape All samples from MW#4 were without odor or any other obvious signs of contamination Soil boring for MW#3 was completed on 5/28198 with all samples collected in the same manner as MW#4 The soil samples removed at a depth of 45 feet and 50 feet both produced an slight solvent odor On 5/29/98 the soil boring for MW#2 was finished using the same sampling method as MW#4 None of the soil samples showed obvious signs off contamination MONITORING WELL INSTALLATION Two monitoring wells were installed in each of the soil borings The deepest (MW#3D, MW44D, MW42D) monitoring wells were placed at the bottom of each soil boring at a depth of 75 feet with a screen length of 5 feet The shallow monitoring wells (MW#3S, MW#4S, MW#2S) were placed with a bottom depth of 55 feet and a screen length of 20 feet (see monitoring well construction drawing attached) MONITORING WELL SAMPLING All wells were purged and developed by Del-Tech(see Groundwater Report enclosed) Flows from 2