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E � URS Mr. Robert McClellon January 31, 2007 Page 3 (ECI) of Richmond, California, loaded the tank onto their truck and transported it to their facility on November 30, 2006 under Manifest Tracking Number 001382376. ECI processed (cut open and destroyed) the tank at their permitted hazardous waste facility. The manifest and certificate of destruction are provided in Attachment 2. RESULTS Soil Vapor. The methane concentrations measured bi-weekly during the fourth quarter of 2006 in VW-1, VW-2, VW-3, VW-7S, VW-7D, VW-8S, VW-8D, VW-9, and VW-10 were less than or equal to 0.1 percent. The methane concentration for the remaining vapor probes ranged from 0% to 0.9% in VW-4, from 0.7% to 7.6% in VW-5S, from 1.7% to 5.2% in VW-5D, from 1.0% to 9.0% in VW-6S, and from 2.9% to 5.1% in VW-6D. During the past two field measurements for landfill gas concentrations (December 15, 2006 and December 28, 2006), the methane concentration within each probe was less than 5.0 percent. Methane concentration in the vapor extraction wells ranged from 0.4%to 16.8%in EW-1 and from 0.2% to 20.3% in EW-2. Methane concentrations in the passive vents ranged from 3.7% to 13.8% in VP-1, from 3.8% to 15.2% in VP-2, from 5.1% to 14.3% in VP-3, and from 5.5% to 12.8% in VP-4. Oxygen concentrations in all sample locations ranged from 0% to 22.8%. Carbon dioxide concentrations in all sample locations ranged from 0.3% to 33.7%. Results for each probe, each extraction well, and passive vent are summarized in Table 1. Groundwater. A groundwater contour map was prepared using the data collected on December 15, 2006 during the groundwater monitoring activities (Figure 2). The groundwater flow direction was shown to be from the west-southwest to the east-northeast direction. For comparison, the groundwater flow direction on June 29, 2006 (Figure 3) was shown to be from southwest to the northeast. However, the groundwater flow direction on September 29, 2006 (Figure 4) was shown to be from the northeast to the southwest,which is the opposite direction as the June 29,2006 groundwater flow direction. VOC constituents were not detected above the analytical laboratory reporting limits in the groundwater sample collected from MW-1, except methylene chloride at 0.5J (estimated)micrograms per liter(µg/Q. The following VOC constituents were detected in the groundwater sample collected from MW-2: acetone at 11 µg/L, carbon disulfide at 0.25J gg/L, and toluene at 3.9 gg/L. Only chloroform was detected at 1.4 µg/L within the groundwater sample collected from MW-3. Acetone, carbon disulfide, chloroform, and methylene chloride are known to be common laboratory contaminants. Of the five reported VOC constituents,primary maximum contaminant levels(MCLs) are established for three: methylene chloride at 5 gg/L by the EPA and California Department of Health Services (DHS), toluene at 1,000 µg/L by the EPA and 150 gg/L by DHS, and chloroform at 80 gg/L by EPA and 100 gg/L by DHS. For one of the two remaining constituents, the taste and odor threshold (TOT) value for acetone is established at 20,000 gg/L. For the remaining constituent, a California State Action Level for Drinking Water (CSALDW) is established by DHS for only carbon disulfide at 160 µg/L. None of K:\Wprocess\25532\WorldEnterprise\Quarterly Rpt\4Q06\CovLtrRpt.doc