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7-Eleven/Stockton 11 February 1990 Monitoring wells MW-7 and MW-8 are representative of the majority of wells at the site. The one exception to the general water level decline is the data from MW-9 which reflect a mounding of the groundwater surface due to a leaking water pipe at the rear of the 7-Eleven Store. In April 1989, this leaking water pipe was repaired and the mounding condition has been corrected. The Groundwater Gradient Maps for July, August, and September, 1989, (Figures 5, 6, and 7) , represent the interpreted groundwater--table elevations beneath the site for each of the three months in this reporting period. The regional groundwater-- gradient direction remains to the east, as reported in the past. The gradient has declined from 0.004 ft/ft to 0.002 ft/ft since the last reporting period. Monitoring well MW-4, which had previously contained free product, remained dry during this reporting period. No other free product was observed. GROUNDWATER SAMPLING AND ANALYSES Sampling of the groundwater monitoring wells, pumping wells Pw--l., PW-2, and PW-3, and nearby domestic wells was performed on six separate occasions during this reporting period. Since wells PW-1, PW-2, and PW-3 are not being used as pumping wells, they T were sampled as monitoring wells. Samples were collected in accordance with Groundwater Technology SOPs 9, 10, 11 and 12 (Appendix B) . Groundwater sampling was conducted by first purging water from each well using a clean polyvinyl chloride (PVC) bailer. Each well was purged of a minimum of Four well volumes of water by hand bailing, unless the well could be purged dry. The groundwater was then allowed to recover to at least 80 percent of the original static water-level prior to sampling. GROVS-DWATER TECHtiQLOCY,INC.