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1 <br /> To reduce the potential for cross-contamination between borings, the augers and <br /> associated equipment were steam cleaned prior to drilling each boring. The sampling <br /> equipment was cleaned with a trisodium phosphate wash and a distilled water rinse prior to <br /> collecting each soil sample. At the completion of the sampling operations, each boring was <br /> backfilled to the surface with a bentonite chips and hydrated to provide a seal to reduce <br /> surface water infiltration. Soil cuttings removed from the borings were contained in one <br /> 55-aallon steel drum, labeled and left onsite. <br /> 2.2 Qualitative Field Screening <br /> To provide a qualitative indication of contamination and to assist in selecting samples to be <br /> analyzed, a portable organic vapor detector was used to screen the samples in the field. A <br /> Photovac photoionization detector (PID) was used to measure total ionizable compounds <br /> in parts per million by volume (ppmv) relative to a isobutylene calibration standard. Each <br /> sample was screened in the field, and the PID readings were recorded on the boring log. <br /> PID readings were 0 ppmv for the samples collected from B-1; however, sample 63967 <br /> collected from B-4 had a reading of 3.3 ppmv. A summary of the PID readings are shown <br /> on Table 1. <br /> For the protection of the field crew, the PID was also used to measure the total volatile <br /> concentrations in the breathing zone prior to and during the drilling of the borings. No <br /> consistent volatile concentrations were detected in the breathing zone. <br /> =.3 Sample Analysis and Results <br /> On April 5, 1990 soil samples were submitted under chain-of-custody to California <br /> Analytical Laboratories/ENSECO in West Sacramento to provide a quantitative <br /> assessment of halogenated volatile organic concentrations. The laboratory is EPA/State <br /> certified to perform the analysis requested. Three samples from boring B-1 and one <br /> sample from B-4 were analyzed for halogenated volatile organics by EPA Method 8010. <br /> The samples were analyzed on a normal turnaround time schedule. <br /> Halogenated volatile organics were not detected above laboratory reporting limits in the <br /> four samples analyzed. The chain-of-custody form and laboratory data sheets are included <br /> in Appendix B. <br /> F4-90-106 3 <br />