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Union Ice Company, 425 North Union Street, Stockton, California ' Phase H Revised Site Assessment, Installation of Oct 28, 1993 Monitoring Wells and Quarterly Groundwater Report Page• 4 ' 3.4 Soil Sampling All soil sampling equipment was thoroughly steam-cleaned before and between sampling ' to prevent cross-contarnination Relatively undisturbed soil samples were taken at intervals of not more than 5 feet in order to evaluate the subsurface materials The soil samples were taken using a California Modified Split Spoon sampler with brass liners The sampler was driven continuously by a wire-line hammer The laboratory samples did not have head space and were immediately sealed in their liners using aluminum foil-lined plastic caps The remaining samples were removed from their liners and used as an aide to the W1F on-site geologist in logging the material at that depth Soil samples collected for laboratory analysis were analyzed using EPA method 8020 for BTEX, and EPA method GCFID (3554/$415) for kerosene The State certified laboratory analyzing the soil samples was Geo-Monitor, Inc , in Hesperia, California Additional samples taken in the Tank #4 excavation were analyzed by GeoAnalytical Laboratories, Inc , Modesto, California S Groundwater Sampling A travel blank provided by the laboratory accompanied the sample vials from the time they were picked up from the lab to the time they were delivered to the lab This travel blank is listed on the Cham-of-Custody, and was analyzed because the samples did contain Icontaminants (Table 1) All sampling equipment, including the bailer and cables used by the sampling personnel, was disassembled and steam-cleaned prior to commencement of sampling These procedures were followed between each well, sampling point, and at the end of the sampling day De-ionized or organic-free water (also provided by the laboratory) was introduced into the bailer as a final stage of cleaning Tlus water was then gently poured into sample vials to be used as bailer blanks These blanks were tested only when their corresponding samples contained contaminants (Table 1) Immediately prior to sampling, water levels and well depth measurements were taken in all I wells at the site Each was evacuated using a stainless steel bladder pump, which does not introduce air into the water column The pH, temperature and electrical conductivity of the water were monitored as the well was evacuated These parameters are noted on a field log (Appendix I) and summarized on Table 3 Instruments calibrated to known standards were used to monitor these parameters At least 5 well volumes were evacuated from each well, and more, if necessary, until the above parameters were stabilized The Isamples were carefully poured from a Teflon bailer into clean glass vials with Teflon-lined 1