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Each well was purged before collecting water samples. Purging <br /> was completed only after water temperature, pH, and conductivity <br /> f <br /> had stabilized. Purged water was contained in a labeled, secured <br /> f 55 gallon drum on site. <br /> The wells were allowed to recover after purging. A water sample ? <br /> was then collected with a fresh bailer. Each sample was divided <br /> among three 40-m1 VOA vials . The vials are supplied pre-cleaned <br /> to exact EPA protocols and contain the appropriate preservative. <br /> The sample vials were labeled as to station, well, time, and <br /> sampler, and documented on the chain-of-cu$tody sheet; they were <br /> then placed into an ice chest, accompanied with a travel blank <br /> and cooled to 40C with ice. The samples were delivered to a <br /> California State Certified Laboratory and signed over to thelab <br /> using standard chain--of-custody procedures . Field notes ` <br /> describing the collection of water samples are included in <br /> Appendix A. <br /> Chemical Analysis Results <br /> The water samples were analyzed at Anlab Analytical Laboratory <br /> (DHS #1468) for Total Fuel Hydrocarbons (gasoline) with BTEX <br /> distinction, utilizing EPA Methods 5030 and 602, respectively. <br /> The analytical results from the water samples (MW1, MW3, MW5, and <br /> MW7) were all Below Reportable Limits (BRL) . MW2 and MW6 <br /> indicate trace amounts of of dissolved gasoline constituents <br /> which are below the 'maximum contaminant levels (MCL) ' set by�` <br /> California Department of Health Services (DHS) . MW4 and MW8 <br /> indicated levels of TFH ( .25 ppm and 61 ppm) and Benzene (2 .2 <br /> Ppb and 3500) . <br /> The current localized impact of TFH-gasoline and benzene on <br /> w is depicted in Figures 5C and 6C. The analytical <br /> ground water p gu Y <br /> results and pertinent reference data are listed in Table 1. <br /> Anlab' s laboratory report is included as Appendix B. <br /> DISCUSSION OF RESULTS <br /> The ground water data obtained during the current monitoring <br /> round show significant changes since the last quarterly <br /> monitoring report . Ground water flow direction is to the south- <br /> southwest with an average gradient of 0 . 001 feet per linear foot; <br /> however, a ground water 'high' exists at MW8 and may be <br /> attributable to local irrigation near this well and a possible ; <br /> slower hydraulic conductivity of this well (see Discussions <br /> section, May 4, 1993 Quarterly Monitoring' Report) . <br /> i <br /> q � <br /> .. 4 I <br /> i <br />