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_ Services--Environmental Health Dtvision (SJCPHS-EHD) in TECC's proposal dated March 15, 1990. This excavation was performed on July 11, 12, and 13, 1990. TFCC performed a further excavation of the waste oil tank area. The report of findings is included in the attached Appendix A. The area was excavated to the saturated zone of the water table - approximately 10.5 feet below surface grade. Analytical results from soil samples collected immediately aboveC- s- the saturated zone indicated concentrations below detection limits; Purgeable Halocarbons were not tested because none were detected in the soil samples collected from the base of the UST. Analysis for \ TPH(g) inadvertently was not tested for in the soil samples collected from the saturated zone. A sample of the pit water was collected and analyzed for TPH(g)/BTEX, EPA Method 5030-8015/602, T Purgeable Halocarbons, EPA Method 601, and Oil and Grease, Standard 71 ` Method 503 D & E. Results indicated concentrations of 1.8 ppm TPH(g), 7.5 ppb STEX, 4.2 ppb (1,2-Dichloroethane) and 2.B ppm Oil and Grease. Recommendation to install four soil borings and three monitoring wells on the site was included in the Auqust 14, 1990 TECO report (Appendix A) . SITE STATUS The monitor well installations for the Phase II soil and groundwater contamination assessment (Remedial Investigation) is presently planned for this site upon approval by SJCPHS-EHD to proceed with this remedial investigation. SCOPE OF WORK During this phase of the investigation and assessment process TECC intends to: 1. Install four groundwater monitoring wells in the approximate locations shown in Figure 3. One, 4-inch well will be installed in the previously excavated area. Three, 2-inch diameter wells will be installed on the property in appropriate locations that will aid in the determination of the groundwater gradient, establish background levels and also help assess possible hydrocarbon contamination in the old gasoline UST tank pit, located to the east of the former waste oil tank pit. The wells will be installed to an approximate depth of 20 feet, or to a sufficient depth to penetrate at least 15 feet below the saturated zone. Should a clay layer, that appears to be a potential aquitard, be encountered at a depth of less than 15 feet through the saturated zone, the well will be completed above this layer. These wells will be installed according to the attached Drilling, Sealing and Sampling Protocol. 2. Install four soil boring in the approximate locations shown in figure 3. The borings will be installed to a depth directly H:\"PS\WP51\TOM\275GRN"A& WRKPLN PAGE 3 OF 5