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Working To Restore Nature samples were 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 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). The groundwater surface has risen approximately 0 62 feet during the second quarter of 1994. The groundwater gradient magnitude and direction was generally consistent during the reporting period The calculated gradients for April (0 007 ft/ft), May (0 007 ft/ft), and June (0 007 ft/ft) are depicted on Plates 3, 4 and 5, respectively. Groundwater flow direction was to the northeast during the reporting period. The direction of groundwater flow has ranged from southeast to northeast since groundwater monitoring was initiated in December 1988 Groundwater samples were analyzed by Sequoia Analytical for total purgeable petroleum hydrocarbons (equivalent to total petroleum hydrocarbons as gasoline [TPHg]) using Environmental Protection Agency (EPA) Method 503018015, 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 5030/8020 Copies of the laboratory reports and chain of custody documentation are attached Results of laboratory analyses indicated dissolved TPHg was detected in the sample from well MW-1 at 1,200 parts per billion (ppb) Benzene was also detected in well MW-1 at 320 ppb TPHd was detected in wells MW-1, MW-3 and MW-5 at 400 ppb, 69 ppb, and 290 ppb, respectively. The laboratory report indicates that the TPHd reported for wells MW-1 and MW-3 contained hydrocarbons less than C14, and MW-3 and MW-5 contained hydrocarbons greater C16 Dissolved TPHd and TPHg concentrations were below laboratory detection limits in monitonng wells MW-2 and MW-4 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 to samples from well MW-1 Dissolved hydrocarbons reported as diesel were detected in wells MW-1, MW-3, and MW-5 during this sampling event Dissolved TPHg and TPHd concentrations were below laboratory detection limits in monitoring wells MW-2 and MW-4. The next sampling event has been scheduled for September 1994 . 38009-1012QSR9d FNL 2