SITE INFORMATION AND CORRESPONDENCE

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s Wells Fargo Bank, Sto�`icton Branch November 27, 1996 Page 2 A. BACKGROUND Phase I Environmental Site Assessment (ESA) Consultant conducted a Phase I ESA of the subject property in October, 1995. The following environmental issues were identified: • According to historical Sanborn fire insurance maps, a gasoline service station existed on the subject property during the 1950's. • During the site reconnaissance, Consultant observed an on-going subsurface investigation at the former Roek Construction facility adjacent, on the southeast corner of the intersection of South Wilson Way and Market Street. • The government record research indicated that a Texaco gasoline service station currently located adjacent, on the southwest corner of the intersection, is identified as a LUST site. Phase II Subsurface Investigation A Phase II Subsurface Investigation was performed by Consultant in February 1996, to further investigate the potential of an environmental impact by the former on-site service station. Soil samples were collected from five (5) geoprobe borings at depths of up to twenty-five (25) feet below ground surface (bgs). All soil samples revealed non-detectable concentrations for total petroleum hydrocarbons as gasoline and diesel (TPH-g and TPH-d) and benzene, toluene, ethylbenzene and xylenes (BTEX). Total recoverable petroleum hydrocarbons (TRPHs) were found at concentrations ranging from 10 parts per million (ppm) to 31 ppm, which is well below Maximum Concentration Level (MCL) of 100 ppm as set forth by the Regional Water Quality Control Board(RWQCB). Based on the above-mentioned analytical results, it was concluded that the on-site soil contamination, although below regulatory action levels, was likely caused by the spilling of waste oil and motor oil at the former on-site service station. There was no indication of diesel or gasoline contamination. Groundwater was expected at a depth of approximately 60 feet bgs, and was not sampled or tested during this subsurface investigation. Agency Correspondence Ms. Linda Turkatte of the SJCEHD contacted Consultant on May 9, 1996. Ms. Turkatte informed Consultant that the subsurface investigations at the neighboring sites had been completed, and that free floating product had been found on top of the aquifer at depths of 60 feet bgs. Assuming a southerly groundwater flow direction, Ms. Turkatte is considering the former gasoline service station at the subject property to be a potential source. Consultant informed Ms. Turkatte of the findings of the February 1996 subsurface investigation. In a letter to Client from the SJCEHD, dated July 3, 1996, Ms. Turkatte has requested that Client conduct additional Phase II activities to further investigate the extent of the groundwater contamination. The agency required the submittal of a Phase II Work Plan on or before September 6, 1996.