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r i Soil samples collected from the bottom of the excavation at the time of the UST removal were analyzed for Total Petroleum Hydrocarbon as gasoline (TPHG) ; Benzene, Toluene, Ethylbenzene and Xylene (BTEX) . The soil samples taken below the UST in native soil showed 4,300 and 540 parts per million (PPM) TPHG at 6 . 5 and 9 feet below grade. The results of these analysis were documented in a report by JPCA dated August 12, 1996. Soil was excavated to about 10 feet and aerated. The excavation was reportedly left open for approximately one year. The excavation was then reportedly back filled with clean fill in October 1997. The Unauthorized Leak or Spill Form is contained in Appendix A. Four Monitoring Wells were constructed in November 1997. The soil in the upper five feet had minor concentrations of hydrocarbon contamination. No detectable contamination for the Oxygenates was found in the soil samples. The groundwater had less than 1 PPM TPHG and 20 ppb Benzene contamination. One groundwater sample from MW-3 had 5 . 6 ppb of MTBE contamination. The remaining groundwater samples had no detectable concentrations, i.e. < 5 ppb, of oxygenates. A potable water well was destroyed in March 1998 . No detectable concentrations of TPHG, BTEX or Oxygenate were found. 3. PRESENT SITE CONDITIONS The site presently has two buildings on site each being approximately 3,000 square feet in area. One building is a one story cinder block structure with a concrete floor and the other a wood framed building with corrugated steel siding on a concrete pad. Also, on site, there are four monitoring wells. The site is used for wooden truss storage by the owners at this time. 4. WELL SURVEY Well information was requested from the City of Tracy, SJCEHD and the California State Water Resources Board. A physical survey was also conducted. The information requested was for an area encompassed by a 2, 000 foot radius circle with the center at the former UST excavation. The City of Tracy reported that there are no wells recorded within the city limits which borders the northern boundary of the subject property. The information for the wells located within a 2,000 foot radius of the former UST area is shown in Figure 3. Appendix B contains 2