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Proposal 10-005 Phase II ESA and Remedial Action/San Joaquin County,CA October 14,2005 Condor identified elevated concentrations of Dieldrin within the surficial soil across the southern portion of the property; however, only ten (10) composited soil samples (two discrete surficial soil samples per composited sample) were collected from approximately 251 acres. In addition, the lateral extent of the Dieldrin-impacted soil was not delineated, or within the Silva-Vosti property. A more detailed Phase II ESA must be performed to determine the area and volume of Dieldrin-impacted soil located at the site, and must be performed to meet standard of care requirements listed below. Furthermore, metals arsenic, lead and mercury should also be analyzed from each sample as required by the California Departm nt of Toxic Substances Control (DTSC) Interim Guidance for Sampling Agricultural Fi School Sites dated August 26, 2002. The Phase II ESA should also evaluate the hazardous or no Razar ature of the burn piles and stressed vegetation identified on the property. The Phase II ESA should also evaluate the lateral and vertical extent of petr -hydrocarbon impacted soil and groundwater beneath the pipelines traversing the property. PROPOSED PHASE II ENVIRONMENTAL SITE ASSESSMENT Phase II Environmental Site Assessment will be prepared for Neighborhood C and laboratory pricing is based on standard five-day turn around time,basis._ Surfzcial Soil Relating to Former Agricultural Activities Based on review of References, the entire property was utilized for agriculture; therefore, the surficial soil must be evaluated for the presence and/or absence of metal and organochloride pesticide residues. Condor's previous environmental work did not detect herbicide residues within the surficial soil; therefore, herbicides will not be included in our proposed work for the entire property. TERRASEARCH, inc. has prepared a proposed grid sampling plan based on 200 and 400 square foot grids. We propose one soil boring be drilled per sampling grid to 2.5 feet below ground surface (bgs) using a direct-push, hydraulically driven drilling rig equipped with stainless steel sampling rods lined with clear Teflon sampling tubes. Each sampling tube will be hand-sawed in the field to obtain specific sample depths. The cut samples will be covered with Teflon sampling tape, capped, labeled and placed within a pre-chilled ice chest. The soil samples will be delivered under chain-of-custody documentation to a State-certified hazardous waste testing laboratory for analysis. Soil samples collected from 0.5-foot and 1-foot will be analyzed for organochloride pesticides and metals arsenic, lead and mercury using SW-846 EPA Methods 8081 and 601013/7000 series. If a 1-foot sample reports a Dieldrin concentration greater than 0.030 milligrams per kilogram (mg/Kg), then the 1.5-foot sample will be analyzed for organochloride pesticides using SW-846 EPA 8081. This process will vertically continue until Dieldrin is not detected or detected below 0.030 mg/Kg. In addition, four discrete soil samples will be collected immediately off-site from the four corners of the property using clean brass TERR,4SEARCH, inc. Page 3