SITE INFORMATION AND CORRESPONDENCE

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Ms. Mary Serra Page 3 of 6 August 10,2004 Site Description: The Station(site)was built on PG&E-owned property in 1961 and is currently inactive. The site is located near the intersection of Airport Way and Perrin Road,approximately 2 miles south of Manteca(Figure 1). The site is approximately 85 feet wide by 100 feet long and is surrounded by a chain-link fence. Gas dehydration operations have ceased and only a control building and odorizer equipment remain on site. The site surface consists of a thin gravel layer (6-inches) over clayey sand. The site is surrounded by a direct access road to the North,Airport way to the west and a cattle pen to the east and south. The land use beyond the roadways and cattle areas are agricultural. Site History The following investigations and reports have been performed for the site: Year Investigation Description Company 1996 Facility Survey Smith 1997 Preliminary Environmental Assessment(PEA) HLA 1998 Site Characterization CH2M HILL 2001 Interim Remedial Action Report CH2M HILL 2002 Implementation Plan CH2M HILL 2002 Remediation Completion Report CH2M HILL 2003 Well Survey ATC 1999-2004 Quarterly Groundwater Monitoring Program (GMP) C112M HILI, Previous characterizations indicate the subsurface soils throughout the site appear to consist primarily of interbedded clay and silt. Groundwater levels recorded over the last three years indicate that the groundwater generally fluctuates between 7 and 13 feet below ground surface (bgs). Based on the historic groundwater elevations, the hydraulic gradient is essentially flat(estimated at 0.002 feet per foot(ft/ft)). Investigations at and around the site were performed between 1997 and 2002 and analyzed soil and groundwater for total petroleum hydrocarbons(TPH)as gasoline(TPH-g),TPH as diesel(TPH-d),TPH as kerosene (TPH-k),TPH as motor oil(TPH-mo),benzene,toluene, ethylbenzene,xylenes(BTEX),glycols and hexavalent chromium[Cr(VI)]. Soil and Groundwater Characterization Historically,elevated TPH-d and TPH-k concentrations were identified in soil at depths between 2.5 to 13.5 feet bgs (maximum TPH-d concentration detected at 7,000 mg/kg). BTEX compounds were detected near the former reboiler and former sump location (northeast portion of the Station). The highest concentrations of BTEX in soil samples were as follows: benzene(8.3 mg/kg) at 12 ft bgs;ethylbenzene (89 mg/kg)at 12 ft bgs;toluene (25 mg/kg) at 12 ftbgs and xylenes (170 mg/kg) at 12 ft bgs. The highest BTEX