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Y 3 U111111111,1111010:11 1:1151il 9.8 and re-zeroed. Each day thereafter, the unit was warmed up and zeroed. The unit was fully charged overnight before use each day. Those samples that yielded positive readings on the photoionizer were retained and submitted for analysis or arc?jval at the laboratory. In addition to these stfmples, samples were collected and designated for analysis frim the unsaturated formation located just above where groundwater was first encoun- tered and at 5 foot BGS for all boreholes. The depth sampled, sample ID, HNu readings and sample fate are presented in Table 3. The ,oil samples were collected utilizing a California modified split-spoon sampler. Prior to collection of these samples, the split-spoon was decontaminated by scrubbing with a bristle brush in a solution of potable water and non-phosphatedetergent (Alconox) , followed by a potable water rinse and a final spray rinse of distilled water. The split-spoon was then lined with laboratory cleansed brass tubes. Once the split-spoon had been driven into the ground and re- trieved, the spoon was opened, screened with an HNu photoionizer and inspected for staining and odors. Each sample collected and associated HNu reading are listed on Table 3. The Hnu readings were utilized to determine the sample fate. If no samples exhibited signs of hydrocarbon compounds, samples were collected only upon nearing depths at which groundwater was anticipated. Soils from tubes not submitted for chemical analysis were used to obtain lithologic information. For those samples collected for chemical analysis, two of the brass tubes were removed. The ends of each tube were covered with teflon sheeting and then capped with plastic end caps. These end caps were then sealed to the tube by wrapping with electrical tape. The tubes were then labeled, inserted into ziplock baggies and placed on ice in an insulated cooler. This procedure was utilized for the first _ sampling day. All subsequent samples were collected in the split spoon and transferred to kiln dried 254 ml glass jars capped with teflon lined lids. As was the case with the brass tubes, once collected, the sample was labeled, inserted into ziplock bag and placed on ice in an insulated cooler. At the end of each day, the samples were delivered with appropriate chain of custody forms to the WESTON analytical laboratory in Stockton, Califor- nia. All chain-of-custody forms are attached. All soil samples submitted for chemical analysis were labeled in the field with an indelible ink pen as they were collected. For each sample, the date and time of sample collectio7, the sam- pler's initials, the project name and the designated analytical parameters were recorded on the label and in the field log book. Soil samples were identified by a well or boring number-depth combination. As two tubes were normally collected at each sampling location (to provide the laboratory with ample sample volume) the tubes were distinguished by lettering them ItAll and "B", with the "All sample being the deeper of the two. For example, a soil sample numbered MWI-35A would ,indicate a roil ._ sample collected at monitor well location mwl from 35 feet BGS and taken from the lower of the two tubes retained.