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Page 5 Cabral-McAdams Property October 16,2006 Job No. 1828-092.02 four Orchard Area locations on the subject property. It was requested that the samples for these analyses be collected at a depth of about ten feet. APPARENT PROBLEM Environmental assessment performed by our firm indicates that past use/handling of pesticides has resulted in impairment of surface soils locally on the subject property. It is noted, however, that soil impairment appears limited to near-surface soils (depths less than 12 inches) within relatively small areas. Elevated concentrations of lead, arsenic, and the organochlorine pesticides 4,4'-DDT and dieldrin were detected in surface soils primarily within or near outbuildings on the property; these contaminants exist in shallow soils locally at concentrations that could be considered a human health concern given the proposed residential subdivision redevelopment of the property. Very low concentrations of motor oil detected within surface soils locally; the very limited occurrence of low concentrations of motor oil is not considered a significant health risk. COMMUNITY PROFILE In accordance with DTSC requirements, a Community Profile Outline for the subject project was prepared by our firm. The purpose of the Community Profile Outline was to compile community information to be used by the DTSC to assess the potential level of community interest in site assessment and closure, and to determine if appropriate public participation activities are warranted. The Community Profile Outline is presented in Appendix B. ENVIRONMENTAL SETTING FACTORS RELATED TO SOIL AND WATER PATHWAYS Geology The subject property is situated on the eastern side of the San Joaquin Valley in the Great Valley geomorphic province of California. According to the Geologic Map of California, San Francisco — San Jose Sheet, the sands, silts, and clays observed by our firm in the general site vicinity are identified as the lower member of the Modesto Formation. The Modesto Formation represents Pleistocene alluvial terrace deposits; the sediments composing these terraces are typically unconsolidated and slightly weathered. The Modesto Formation in the subject area overlies other Cenozoic deposits and the Cretaceous geologic formation of the Great Valley Sequence. The formations within the sequence generally dip shallowly to the west and are several thousand feet thick. The Great Valley sediments are in turn underlain by the Mesozoic metamorphic and plutonic rocks of the Sierra Nevada. The surface soils encountered at the site generally consist of brown silty fine sands and sandy silts; these deposits are considered moderately to highly permeable. The subsurface soil conditions encountered in our exploratory borings on the subject property are