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supervision of a San Joaquin Local Health District - Environmen- tal Health Division representative. Monitor Well logs for each well (attached) presents the lithologies encountered, including first occurrence of saturated materials and well construction details specific to each well . Soil Sampling During the drilling of the three monitor well boreholes, soil samples were collected from each location at 3 foot intervals down to what is interpreted as the upper most groundwater. Two more samples were collected from the monitor well boreholes, one at 5 feet and another at 10 feet below the point first groundwa- ter was encountered all samples were collected using a split spoon sampler. Three exploratory soil boreholes (designated BH1, BH2 , and BH3) were drilled and sampled at a 3 foot interval down to first groundwater. One of the 3 exploratory boreholes (BH2) was continued to 40 feet BGS sampling every 5 feet below first groundwater. All samples were examined for any staining and odors which could be a result of contact with suspected contaminants. Additionally, samples were screened with a photoionizer (The instrument used was an HNu model P101 equipped with an 11.7 eV bulb) . Before use, the unit was allowed to warm up for approxi- mately 5 minutes and zeroed. Those unsaturated samples appearing visually stained, odorous or otherwise contaminated, or producing a response on a field screening instrument (an HNu photonizer) were submitted to the laboratory. Three soil samples per explor- atory soil boring and one sample per monitor well boring were submitted for chemical analysis. The samples not initially selected for chemical analysis have been archived at the labora- tory for possible future analysis. Prior to collection of these samples, the split-spoon was decon- taminated by scrubbing with a bristle brush in a solution of otable water and non-phosphate detergent (alconox) , followed by potable water rinse and completed with a final spray rinse of distilled water. Once the split-spoon had been driven into the ground and re- trieved, the spoon was opened, the soil was screened with an HNu photoionizer and inspected for staining and odors. All soil samples collected for analysis were placed into two 250 ml. clean kilned glass bars, capped and appropriately labelled. Labels were filled out with an indelible ink pen as they were collected and for each sample, the date and time of sample collection, the project name and the designated analyses were recorded on the label . Two sample 3ars were normally collected at each sampling location to provide the laboratory with extra sample volume. Soil samples were identified by a well number-depth combination. For example, a soil sample numbered MW1-35 would indicate a soil sample collected at monitor well MW-1 from 35 feet BGS. The far were then sealed in zip-lock baggies and placed in an insulated