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Emergency Remediation - 2480 Tracy Blvd., Tracy, CA. • Page 18 1 Samples were recovered from the selected sampling locations by brushing aside the surficial soil and driving a 2 in.-diameter by 4 in.-long brass sampling tube into the treated soil until the tube was completely full. (Note: Before Soil Spread I was formally sampled, a trial sample - designated TRIAL-N - was recovered from an arbitrary location in the portion of the spread lying to the north of the basement excavation. Test results from that sample, which showed that it contained no detectable concentrations of the analytes of concern, were used to help evaluate the optimal methods and duration of aeration that would be required to meet the goals of.the ' emergency remediation plan.) Following sample recovery, the sample tubes were cleaned externally, the ends covered with aluminum foil and closed with tightly-fitting plastic caps secured by adhesiveless tape. Each sample tube was then labeled for identification, entered into chain-of-custody control, packed on chemical ice, and placed in an electric sample cooler for transport to I Chromalab Inc.'s laboratory in Pleasanton, California where they were analyzed for the following suite of analytes. Analyte Method of Analysis Total Petroleum Hydrocarbons EPA Method 5030/8015 (as Gasoline) Benzene EPA Method 8020 Toluene EPA Method 8020 Ethyl Benzene EPA Method 8020 Total Xylenes Isomers EPA Method 8020 The results of the analyses performed on sample TRIAL-N and on the soil samples recovered from each of the five spreads of treated soil are presented in Table 3. Analytical results from the samples from Soil Spreads 1, 3, 4, and 5, with one inconsequential exception (Sample A5 from Soil Spread No. 6) show that none of soil in those spread contained any detectable concentrations of total petroleum hydrocarbons (quantified as gasoline) although very minor traces of some BTEX compounds (none exceeding 0.031 ppm)were detected in a small number of the samples. Both of the samples recovered from Soil Spread No. 2 contained barely detectable concentrations of total petroleum hydrocarbons (1.7 ppm or less) and proportionate trace concentrations of the BTEX compounds (except for toluene, which was absent from both samples). Soil Spread No. 2 was the smallest of the seven spreads used to treat the r