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locations. Underground Services Alert (USA) was notified prior to drilling. Drive samples were screened with a portable organic vapor analyzer(OVA), and positive results were to be submitted to Clayton Environmental Services in Pleasanton, CA for TPHg and BTEX analyses. None of the samples yielded positive results with the OVA, so none were submitted for analysis. The borings were backfilled to the surface with neat Portland cement. Between drilling locations the drilling auger and samplers were steam cleaned to reduce the possibility of cross contamination between boreholes. Cuttings generated during drilling were disposed on-site since OVA readings were negative. Drilling of boreholes was accomplished using a mobile drilling rig equipped with four inch diameter hollow stem augers. The boreholes were extended to a maximum depth of sixty (60) feet. The San Joaquin County Flood Control District (Mr. Bryan Jones) reports that the depth to ground water in the vicinity of the subject property is 60 feet and the ground water flow direction is from east to west(Kleinfelder Preacquisition Site Assessment- Southeast intersection of March and West Lanes, Job No. 24-2115-10). Drilling was terminated at 60 feet when no ground water was encountered. During drilling, a geologist from pH7 directed the field operations and logged the soil samples as they were obtained using the Unified Soil Classification System (refer Figures 4,5,6 &7). Soil samples were collected at a maximum of five foot intervals using a modified California sampler with brass sample tubes. The ends of the brass tube were covered with aluminum foil, then plastic end caps, and finally wrapped with a non-petroleum containing tape. Sample horizons were screened in the field using a portable organic vapor analyzer(OVA) to check for the presence of fuel compounds in order to assist in sample selection for laboratory analysis. A negative result with the OVA was cause to exclude a sample from laboratory analysis. Since no samples yielded positive OVA result, none were submitted to the laboratory for analysis. All of the samples were immediately refrigerated for possible laboratory analysis within the following 14 days for Total Petroleum Hydrocarbons as Gasoline (TPHg) utilizing EPA Method 5020, and BTEX utilizing EPA Method 8015. Formal chain-of-custody records have been maintained. Since ground water was not encountered, no water samples were obtained for analysis. The depth to ground water, coupled with the low permeability of the soils and the lack of an identified off-site source of contamination, virtually eliminates the possibility for lateral migration of petroleum hydrocarbons beneath the property A composite sample of surficial soils was collected and submitted to Clayton Environmental for pesticide analysis by EPA Method 8080. Formal chain-of-custody records were maintained. The results were None Detect (ND) for all tested organochlorine pesticides and polychlorinated biphenyls (refer to attachments). GEOLOGICAL AND HYDROGEOLOGICAL CONDITIONS The near surface materials are composed of sandy clays and silts with occasional beds of silty sands (refer to the attached boring logs performed as part of the Weber Ranch Office Park geotechnical investigation by Kleinfelder, Stockton, CA,March 9, 1990). Two holes drilled under the supervision of pH7 Environmental encountered similar materials to depths of 60 feet (refer to Figures 4 &5). No ground water was detected. The predominant ground water gradient direction in the vicinity would be south toward the Calaveras River and/or west toward the axis of the San Joaquin Valley. -3-