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jawAC Working to Restore Nature GROUNDWATER MONITORING On March 30, 1994, a RESNA technician measured the water levels in wells MW-1 through MW-5, well RW-1, and piezometer PZ-1 and collected groundwater samples from the wells for subjective analyses Groundwater samples were also collected from wells MW-1 through MW-5 for laboratory analyses The field methods used are presented as an attachment to this report. Floating product or product sheen was not noted on samples from the wells (Table 1) The depth to water measurements and the elevations of the well casings (Table 1) were used to evaluate the groundwater flow direction and gradient beneath the site (refer to attached Field Procedures) On March 30, 1994, the groundwater gradient beneath the site was 0 008 with a flow direction toward the northeast (Plate 3) Since the previous monitoring event, the groundwater surface has rose approximately 0 52 foot The direction of groundwater flow has ranged from southeast to northeast since groundwater monitoring was initiated in December 1988 Groundwater samples were analyzed for total purgeable petroleum hydrocarbons(equivalent to total petroleum hydrocarbons as gasoline [TPHg]) using Environmental Protection Agency (EPA) Method 5030/8015, total extractable petroleum hydrocarbons (equivalent to ., total petroleum hydrocarbons as diesel [TPHd]) using EPA Method 3510/8015 (modified for gasoline and diesel), and for benzene, toluene, ethylbenzene, and total xylene isomers using EPA Method 5030/602 These samples were analyzed at Sequoia Analytical Copies of the Chain of Custody Records and laboratory analysis reports are attached Results of laboratory analyses indicated dissolved TPHg was detected in samples from wells MW-1 and MW-4 at concentrations of 1,500 parts per billion (ppb) and 67 ppb, respectively Benzene was also detected in well MW-1 at 430 ppb TPHd was detected in wells MW-1 MW-3 and MW-5 at 320 ppb, 71 ppb, and 420 ppb, respectively The laboratory report indicates that the TPHd reported for wells MW-1 contained hydrocarbons between less C14, and MW-3 and MW-5 contained hydrocarbons greater C14 Dissolved TPHd and TPI-Ig concentrations were below laboratory detection limits in monitoring well MW-2 Results of laboratory analyses are summarized in Table 2 SUMMARY AND RECOMMENDATIONS The groundwater flow direction and gradient were generally consistent with those evaluated during previous events Dissolved gasoline hydrocarbons were detected in samples from wells MW-1 and MW-4 Dissolved hydrocarbons reported as diesel were detected in wells 0422iew/38009-10 2