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Mohr-Fry Ranches 950 Industrial Drive Stockton California Groundwater Sampling Report AuguA 1994 Narrative On August 4, 1994, WBF, Inc, in conjunction with HKM Groundwater, conducted field measurements, well pumping and groundwater sampling on three groundwater monitoring wells ' located at this site(Figure 2) All samphng equipment, including the bailer and cables used by sampling personnel, was disassembled ' and steam-cleaned prior to commencement of samphng These procedures were followed between each well, sampling point, and at the end of the sampling day De-ionized or organic-free water (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 bailer blanks were not tested unless their corresponding samples contained contaminants Immediately prior to sampling, water levels and well depth measurements were taken in all wells at the site Each well 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 ' wells were evacuated (Table 2) These parameters are noted on the Field Logs (Appendix B) Instruments calibrated to known standards were used to monitor these parameters At least three (3) well volumes were evacuated from each well, and more, if necessary, until the above parameters were ' stabilized Once stability was achieved, the samples were collected, labeled and chilled in an ice chest with Blue Ice ' The samples were carefully poured from a Teflon bailer into half gallon plastic containers and clean glass vials with Teflon-tuned screw caps provided by the laboratory Care was taken to ensure that no ' air space existed in the vials by inverting to check for bubbles and re-sampling if necessary The samples were analyzed or extracted within 14 days according to their EPA methods ' 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 returned to the laboratory This travel blank was only analyzed if the samples contained contaminants The travel blank and sample vials were then logged on a Chain of ' Custody Record and dehvered to GeoAnalyhcal, Inc, a State certified laboratory in Modesto, Cahfonua The analysis requested for the water samples were EPA method 602 for BTX&E compounds, and EPA method GCFID 3510 for Diesel The analytical results are listed m Table 3 of ' this report Groundwater elevations from 8/4/94 were used to construct a groundwater gradient map and calculate the gradient at 0 0016 ft/ft at N 14°W(Figure 3) Monthly water level readings were conducted since 1