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Former Discovery Chevrolet September 16, 1998 Tracy,California Re ort on Remedial Work At the conclusion of the overexcavation work, approximately 1*ll-cdbi,c yards---o hydrocarbon-impacted soil were removed from the excavation. On August 13, after discussing sampling procedures and requirements with Mr. Ron Rowe, R.E.H.S. of the SJCPHS-EHD, twelve composite soil samples (one per 50 cubic yards) were collected from the hydrocarbon-impacted soil stockpiled temporarily at the site. Each composite soil sample consisted of two sample locations (as discrete samples) per composite. The composite samples were collected from the stockpiled soil by selecting random locations accessible around the soil pile, removing approximately two feet of soil, and then driving a clean brass sleeve into the soil pile at the selected location. Mr. Jeff Wong of the SJCPHS- EHD witnessed the collection procedures for the twelve composite soil samples collected from the stockpiled soil. On August 14, Mr. Ron Rowe, R.E.H.S. at the SJCPHS-EHD indicated, a Grading Permit from the City of Tracy was required prior to backfilling the excavation. Subsequently, the backfilling was delayed for four days and some caving of the excavation sidewalls occurred while the grading permit was being acquired. A copy of the Grading Permit is included in Appendix A. The final dimensions of the excavation were approximately 32 feet wide by 40 feet long by 12 feet deep. Anal tical Results of Soil Sam les The collected soil samples were prepared and chilled for transport under chain-of-custody COC procedures on the sampling date-of-collection(COC) p plzng date of collection and sent to KifI'Analytical, a State- certified laboratory in Davis, California (Certification No, 2236). The requested analyses included: Total Petroleum Hydrocarbons as gasoline (TPHg) using U. S. Environmental Protection Agency (EPA) Method 8015 (modified); the volatile aromatics benzene, toluene, ethylbenzene, and total xylenes (BTEX) and the fuel oxygenate methyl tertiary butyl ether (MTBE) using EPA Methods 8020 or 8260B. Additionally, selected stockpile samples were analyzed for Total Lead by EPA Method 7420. The soil samples were analyzed on expedited turnaround times because of safety concerns for backfilling of the excavation, which was undergoing collapsing sidewalls and was located near a residential area. The analytical results for the sidewall, floor, and-composite soil samples collected from the site are summarized in.Table 1. Copies of the laboratory and P ry COC reports are included in Attachment C. Backfilled Soil CAfter notification of the SJCPHS-EHD, the excavation was backfilled between August I8 and 20 with Class II aggregate baserock material from the RMC Kerlinger facility in Tracy, California. Approximately 800 tons of compacted aggregate baserock material was used to backfill the excavation at the site. Soil compaction testing of the backfilled aggregate material was performed by Construction Testing and Engineering, Inc. (CTE) in Tracy, California. A copy of CTE's field compaction testing report is included in Attachment D. 3001-2 Lovx 3 HORIZON ENVIRONMENTAL INC. i.