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Union Ice Company, 425 North Union Street, Stockton, California Phase II Additional Site Assessment, Installation of Sept. 9, 1993 Monitoring Wells and Quarterly Groundwater Report Page: 4 1 ' 3.4 Soil Sampling All soil sampling equipment was thoroughly steam-cleaned before and between sampling ' to prevent cross-contamination Relatively undisturbed soil samples were taken at intervals of not more than 5 feet m 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 lmers and used as an aide to the WHF on-site geologist in logging the material at that ' depth Soil samples collected for laboratory analysis were analyzed using EPA method 8020 for ' BTE7, and EPA method GCFID (355018015) for kerosene The State certified laboratory analyzing the soil samples was Geo-Monitor, Inc, in Hesperia, California 3.5 Groundwater Sampling ' A travel blank provided by the laboratory accompanied the sample vials from the tune they were picked up from the lab to the time they were delivered to the lab This travel blank is listed on the Chain-of-Custody, and was analyzed because the samples did contain contaminants (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 This 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) I Immediately prior sampling, P nor to sam lin , water levels and well depth measurements were taken in all 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 Ieast 5 well volumes were evacuated from each well, and more, if necessary, until the above parameters were stabilized The