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' Site Background Information Chapin Brothers Investements, Inc Page 8 of 12 Samples were collected at five-foot intervals, with samples were preserved by covering both ends of the brass sleeve with Teflon sheets, capping and sealing with tape TPH-g, BTE&X and oxygenated compounds were not detected in soil samples collected from the location ofwell MW-7 Soil samples collected from depths of 15, 20 and 25 feet bsg were analyzed 1 REMEDIATION WELL INSTALLATION On 29 July 1997, three in-situ air-sparing (IAS) points (IAS-7 through IAS-9) were installed to depths of 25 and 15 feet bsg using AGE'S van-mounted Geoprobe 5400 soil probing machine Two probe borings were completed as IAS points using one 21-inch long, 3/8-inch I D stainless steel screen implant attached at 25 feet bsg to an anchor tip One additional probe boring was completed using one 21-inch long, 318-inch I D stainless steel screen implant set at a depth of 15 feet bsg ' Vinyl tubing (318-inch O D ) was extended from the spargmg screen implant to the surface and a filter pack (fine glass beads) was installed around the screen implant from a depth of 20 to 25 feet bsg Bentonite sand(#8 bentonite)was used to make a4-foot plug above the filter pack and the wells ' were grouted to surface grade with portland cement An eight-inch traffic box was installed at the surface for each IAS point SOIL VAPOR EXTRACTION- MASS OF RECOVERY Between 15 April and 19 September 2003, the ground water extraction and treatment system Processed approximately 302,703 gallons of water The total volume of ground water treated as of ' 30 September 2003 is approximately 2,459,705 gallons GROUND WATER REMEDIATION Based on an EHD office meeting conducted on 05 April 2000 the EHD and the Central Valley ' Regional Water Quality Control Board(CVRWQCB) verbally agreed on the use of ground water extraction and treatment to mitigate the site As note above an SVE/IAS system has been installed and operated at the site to remediate hydrocarbon-impacted soil and ground water Over the course ' of the remediation, rising ground water elevation has submerged a significant portion of contaminated soil below the ground water table and capillary fringe Under this condition, hydrocarbon-impacted ground water has remained and the overall influence of the IAS system has demonstrated diminishing effectiveness at reduction of dissolved hydrocarbons Areas in the eastern portion of the site and at the northwest corner of the site have not demonstrated a sustained reduction of dissolved hydrocarbons Ground water has remained impacted The implications from the set of March 2001 aquifer ground water extraction tests were the ' Advanced GeoEnvironmental,Inc