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2-R -- On May 5, 1995, a soil vapor extraction system consisting of an R.S.1 SAVE system was installed at the subject site. The vapor extraction system was installed per San Joaquin Valley Unified Air Pollution Control District(SJVUAPCD)Permit conditions. The vapor extraction system consists of an internal combustion engine with catalytic converters mounted on the exhaust. The system was configured such that soil vapors could be extracted from either vapor well VEW-1 and/or monitoring well MW-1. The system was started on May 5, 1995, and has operated through October 4, 1995, at which time it was temporarily removed from site. On November 27, 1995, the system was returned to the subject site and restarted. An air sparge system was installed for use in conjunction with the vapor extraction system. The air sparge system consisted of a one horse power electric motor which powers a 10-cubic feet per minute (CFM) oil-less compressor. The compressor injected air through an air sparge point located midway between VEW-1 and MW-1 (Figure 2). The air sparge system was started on May 31, 1995 and operated intermittently through August 30, 1995, at which time its operation began to coincide with the operation of the R.S.I. system. On April 29, 1997, Apex received permission from the San Joaquin County Environmental Health Division (SJCEHD)to shut down the air sparge and vapor extraction system due to low influent soil vapor concentrations to the vapor extraction system. As of April 29, 1997, the remediation system has extracted a total of 1,730 pounds of total petroleum hydrocarbons (TPH), as gasoline, and 19.9 pounds of benzene. Apex submitted a Over Excavation & Groundwater Removal Workplan dated September 10, 1997, proposing over excavation; de-watering and sampling of the bulk loading rack and tank basins during the nine UST removals. UNDERGROUND STORAGE TANK REMOVALS The two 350 gallon USTs identified as T-8 and T-9 (350-gallon kerosene and 350 gallon cleaning solvent USTs respectively)were exposed by BC Construction (BC) on August 16, 1998. T-9 (350-gallon cleaning solvent) was excavated and removed by BC on August 17, 1998. T-8 (350- gallon kerosene) was excavated and removed by BC on September 8, 1998 (Figure 3). After exposing the tops and prior to removal of the USTs, the UST interiors were washed, purged of wash water and purged of combustible vapors with dry ice. Associated piping and.one dispenser pad were also excavated and removed. The seven 10,000 gallon USTs T-1 through T-7 (three 10,000-gallon diesel and four 10,000- . gallon un-leaded gasoline tanks)were exposed by BC Construction(BC) on September 4, 1998. The seven 10,000 gallon tanks were removed by BC on September 8, 1998 (Figure 4). After exposing the tops and prior to removal of the USTs, the UST interiors were washed, purged of wash water and purged of combustible vapors with dry ice.