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i SOIL PROFILING, EXCAVATION, AND SAMPLING On June 19, 1997, HK2 drilled one 4-inch-diameter boring to approximately 3.5 fbg in the center of the UST cavity to collect one sample from the soil placed into the excavation in December 1996. The sample was necessary to complete the soil profiling process prior to re-excavation so aboveground stockpiling could be avoided. The sample was submitted to North State Environmental (NSE; a state-certified laboratory) for analysis of soluble lead (California Waste Extraction Test) and reactivity, corrosivity, and ignitability. A copy of the laboratory report is in the Appendix. On June 26, 1997, HK2 excavated the Class II base material and visqueen wrapped hydrocarbon- affected soil from the tank cavity, collected two soil samples from the tank cavity sidewalls, transported the hydrocarbon-affected soil to a disposal facility, and backfilled the excavation with the Class II material and imported pea gravel (6.5 to 0.5 fbg) and concrete (0.5 fbg to grade). The hydrocarbon-affected soil(approximately 18.1 tons)was transported to Bay Area Soils in Richmond, California. A copy of the waste manifest and scale log are in the Appendix. The soil samples from the tank cavity sidewall (T1-1.5 and T2-6) were collected under the r supervision of Ms. Margaret Lagorio and Mr. Bruce Askanas of the SJCPHS. The location of these samples is shown in Figure 3. Sample T1-1.5 was collected in the same area as Sample NEcorner@1' which was collected from a stained soil area during tank removal activities, but was never analyzed (refer to the tank removal report). T1-1.5 and T2-6 were submitted to NSE for analysis of TPH-G, TPH-D, and TPH as motor oil (TPH-MO; Modified EPA Method 8015). A copy of the laboratory report is in the Appendix. FINDINGS • The color of the hydrocarbon-affected soil in the visqueen was grayish black (N2). The color of the sidewalls of the excavation was moderate brown (5 YR 4/4). • Groundwater was not encountered in the excavation. • The hydrocarbon concentration in soil samples collected from the sidewalls of the excavation. was below the laboratory reporting limit. CONCLUSION • The lateral and vertical extent of waste oil affected soil observed during tank removal activities as has been removed from the site. In'the opinion of HK2, no further action on this issue is warranted. 2