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Mr. Ron Rowe March 6, 2000 Page Two capacity used oil UST and associated piping were removed from the excavation and inspected for evidence of cracks, breaches, or other failures. No evidence of a breach was observed in the UST or associated piping. Excavated backfill and native soils surrounding the excavation displayed no evidence of contamination. A 12 inch concrete pad was located at the base of the excavation at a depth of 9 feet below grade. A concrete coring machine was used to core through the concrete pad for soil sampling purposes. Evidence of soil contamination(i.e., odors and staining) was first observed beneath the concrete pad. The contamination appeared to be the result of a release from a faulty oil/water separator located in the floor of the TLE lube pit bay at an approximate depth of 10 feet below grade and approximately 10-12 feet from the UST excavation. Inspection of the oil/water separator indicated that seals had not been installed on the separator plumbing. The separator was immediately repaired and potential for future release is not anticipated. Ms. Tish, Hazardous Materials Management Specialist, County of San Joaquin Department of Environmental Health, was on-site to direct soil sampling activities. Soil samples were collected by Steve Richardson, California Registered Geologist. Following removal of the UST, two soil samples were collected from beneath the 12 inch concrete pad of the UST at a depth of 9 feet below grade, which included one soil sample from the west end of the UST excavation and one soil sample from the northeast corner of the UST excavation. Additionally, one sample was taken from each of two stockpiles present on-site that were a result of the UST excavation. All excavation samples were collected with a stainless steel hand auger lined with 2" x 6" brass sleeves. Excavation soil samples were collected from undisturbed native soil, capped with teflon and plastic end caps, and immediately placed on ice for preservation. New disposable latex sample gloves were donned prior to each sample collection. Each sample was submitted, through proper chain of custody procedures documenting each stage of possession and handling, for laboratory analysis. Soil samples collected at the site were sent to Clayton Environmental Consultants (Clayton), a State of California-certified laboratory, in Pleasanton, California. Three soil samples were submitted for chemical analysis of total petroleum hydrocarbons - gasoline range (TPH-G 801518020); total petroleum hydrocarbons - diesel range (TPH-D 8015); benzene, toluene, ethylbenzene,and xylene(BTEX 801518020); chlorinated hydrocarbons(CL-HC 8010);cadmium, chromium, lead, nickel and zinc (ICAP METALS 6010A); and polychlorinated biphenyls (PCB 8080). Soil analytical results are summarized in Table 1 and Table 2. 00268114.919