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<br /> PHASE II ENVIRONMENTAL SITE ASSESSMENT
<br /> REPORT
<br /> PROPOSED NEIGHBORHOOD G SITE
<br /> PORTIONS OF ASSESSOR PARCELS
<br /> 209-050-06,209-050-02,209-040-12, AND 209-040-13
<br /> MOUNTAIN HOUSE,SAN JOAQUIN COUNTY
<br /> CALIFORNIA
<br /> EXECUTIVE SUMMARY
<br /> Condor Earth Technologies, Inc., (Condor)conducted a Phase II Environmental Site Assessment(Phase H)
<br /> for the proposed Neighborhood G site located approximately one-half mile west of the intersection of
<br /> Mountain House Parkway and Byron Road in San Joaquin County, northwest of Tracy, California, in
<br /> general accordance with the Phase II Environmental Site Assessment Work Plan, prepared by Condor,
<br /> dated September 25, 2001. The primary objectives of the Phase II were to evaluate potential contamination
<br /> issues and contaminant exposure levels associated with historical land use practices at the site. The
<br /> proposed neighborhood site consists of approximately 240 acres of generally flat land and comprises
<br /> portions of Assessor Parcel Numbers (APNs) 209-040-12, 209-040-13, 209-050-02, and 209-050-06 in
<br /> Sections 4, 5, 8 and 9, Township 2 South, Range 4 East of the Clifton Court Forebay, California
<br /> Quadrangle, 7.5 minute, United States Geological Survey (USGS) Topographic Map, dated 1978. At the
<br /> time of sampling activities conducted as part of the Phase II, the site and surrounding areas contained
<br /> vegetative cover consisting of alfalfa and corn. The site is bounded by agricultural land.
<br /> A Phase I Environmental Site Assessment Report, dated October 29, 2001, was prepared for the site by
<br /> Condor. According to information contained in the above referenced document, the site was historically
<br /> used to cultivate alfalfa, sugar beets, corn, wheat, and tomatoes. Potential contamination issues primarily
<br /> include residual pesticide and herbicide concentrations in surficial soils.
<br /> Condor personnel collected soil samples from the site on September 28, 2001. Ten locations(I through 10)
<br /> dispersed across the approximately 240-acre site were selected for soil sample collection. Two additional
<br /> soil sample locations (l I and 12) were selected in the southwestern corn-producing portion of the site to be
<br /> analyzed for organophosphorus pesticides. One discrete surface sample was collected at each location from
<br /> a depth of approximately zero to six inches below grade. Surface soil samples collected from two
<br /> consecutively numbered locations were composited by the laboratory resulting in a set of five two-to-one
<br /> composite surface samples(sample numbers 1-2, 314, 5-6, 7-8,and 9-10). These composite surface samples
<br /> were analyzed for organochlorine pesticides by EPA Method 8081A, and chlorinated herbicides by EPA
<br /> Method 8151A. Two discrete samples (sample numbers 11 and 12) were analyzed for organophosphorus
<br /> pesticides by EPA Method 8141A.
<br /> The laboratory analytical results indicate that the organochlorine pesticides gamma-BHC (lindane), DDD,
<br /> DDE, DDT, endosulfan I, endosulfan II, endrin, endrin aldehyde, heptachlor, and kepone, and the
<br /> chlorinated herbicide MCPP were detected in the composite samples. Each of these constituents was
<br /> detected below the laboratory reporting limits and the reported values are estimated concentrations. The
<br /> organophosphorus pesticides azinphos-methyl, bolstar, chlorpyrifos, coumaphos, demeton, diazinon,
<br /> dimethoate, disulfoton, ethoprop, ethyl parathion, famphur, fensulfothion, fenthion, merphos, methyl
<br /> parathion, mevinphos, 0,0,0-triethylphosphorothioate, tetrachlorvinphos, thionazin, tokuthion, and
<br /> trichloronate were detected in at least one of the discrete soil samples analyzed for these constituents.
<br /> Bolstar, chlorpyrifos, demeton, diazinon, dimethoate, disulfoton, ethyl parathion, famphur, fensulfothion,
<br /> i, CONDOR
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