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collected from MWl, MW2 , MW3, MW4, MW5, MWG and MW7 . Of these laboratory analyzed samples, all samples were Below Reportable Limits (BRL) except MW4 . The analytical results and the pertinent gathering data are listed in Table 1, and the laboratory report is included in Appendix D. HYDROCARBON CONTAMINATION The wells sampled during this monitor round indicate non detect for petroleum hydrocarbons for all wells except MW4 , which indicated very low levels of TFH ( 093ppm) and no volatile aromatic hydrocarbons. It is unclear, with the limited samples available, what effect the partial recharge of the ground water table in this area has had upon natural bio-degradation taking place at the site. While the overall ground water gradient remains low, with a slope of . 0038, it has increased slightly (from . 0025 in June, 1992) with a increase of approximately 1 foot in ground water elevation The aquifer test data along with the lithologic cross section and hydraulic gradient (Problem Assessment Report, December 5, 1989) across the site infer that velocities of the ground water are such that natural bio- degradation is taking place . The restoration of a sampling point at MW4, which lies along the dip of the ground water gradient between MW3 and MW6, enhances detection and/or verification of contamination. Discussion In addition to the quarterly sampling investigation at this site USA Petroleum Corporation contracted Western Geo-Engineers (WEGE) to restore MW4 . On September 15, 1992 , a WEGE geotechnician uncovered and restored MW4 to operable condition This well was sampled on October 9, 1992 (see Appendix B and Table 1) . The restoration of MW4 conforms with a needed sampling point in this area and complies with regulatory concerns expressed in letter correspondence of August 19 , 1992 and September 30, 1992 from San Joaquin County Public Health Services, Environmental Health Division (PHS/EHD) , see Appendix A. The letter of September 30, 1992 suggested that ' a need for, additional ground water plume definition in the area of MW4 & MW6 will be determined after sampling of monitor well #4 ' The sampling has occurred and two periods of ground water analysis from this well, October and December, 1992 (see Table 1) , indicate that continued sampling of this well and the ad3acent MW' s are sufficient to monitor present ground water quality at this site . 4