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T. 1 k conducted for possible hydrocarbon emissions using a"i HNU instru- ment. Monitoring was performed on an ongoing bas..s within the excavation, on the periphery and generally on the downwind (east side) of the excavation during all excavation activities. The HNU reading generally remained below 5 ppm with occasional peaks not exceeding 24 ppm. These peaks were detected starting on June 28, 1989 and continued until the east wall excavation was completed on June 30, 1989. Warning signs were posted on the excavation perimeter as of the first peak. June 28,1989 The results of the previous day's soil sampling were received. The analytical results for all soil samples collected throughout the duration of the remedial project are presented in tabular form on Table 1. The analytical reports are presented in Appendix B. Based on this information, loading and tranL.porting of the excavated soil began and a total of 72 cubic yards soil were transported to Casmalia Resources. Per the sidewall sample analysis, both the east and south sidewalls were each cut back 10 feet. The west sidewall was also cut back 5 feet even though no TPH concentrations were detected in order to provide room within the excavation for a ramp to lower the excavation equipment. Excavation continued and two samples were collected from the -„ removed soils. These samples are designated lift #3 and OVER #2. OVBR #2 was the stockpile of soils removed from the west wall. ,Tune 29 1989 } --1/ A total of 144 cubic yards of material were loaded and shipped. Of this total, 38 cubic yards were shipped to Casmalia Resources „a and 108 cubic yards were shipped to Forward, Inc. Excavation continued with the further removal of 10 feet from the east and south sides. The newly exposed sidewalls were sampled at 25 feet below ground surface and the samples were designated Pit 20E25 and Pit IOS25. The stockpiles of excavated soils were sampled and the samples were designated lift #4 and lift #5. June- 30. 1989 Loading and transportation of soils continued with 162 cubic yards of soil being transported to Casmalia Resources and 198 cubic yards of soil transported to Forward, Inc. Analytical results indicated the east sidewall was free of petroleum hydrocarbon compounds but the south sidewall contained concentrations of TPH in excess of 100 - ppm. Additional excavation of the south side continued with removal of soils until it was perpendicular with the north edge of the sidewalk along Washington Avenue. A sample, designated Pit - 20S25, was taken to evaluate the petroleum hydrocarbon presence within the south sidewall-. Confirmation samples of the each sidewall was also taken and was designated Pit 20E25C. The C following the sample ID number indicates a confirmation sample. J 6