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Mr. Robert McClellon July 28, 2006 Page 3 temperature, conductivity) were recorded on a Well Development Log form (Attachment 2). The purged water was placed in 55 -gallon drums for appropriate disposal. Quarterly Monitoring Activities On June 19, 2006, the three groundwater monitoring wells were sampled using the following procedures: • The water level was measured from each monitoring well, using an electronic water level sounder. • Prior to groundwater sample collection, each well was purged using a bailer. During purging, groundwater parameters (pH, temperature, conductivity, and turbidity) were recorded on the Monitoring Well Sampling Log form (Attachment 3) at least once per well casing volume. Purging was completed when the groundwater parameters had stabilized to within 10 percent. The purged water was placed in 55 -gallon drums. • A groundwater sample was collected from each well, using a bailer. The groundwater samples were placed into the analytical laboratory prepared sample containers. • The groundwater samples were labeled and placed in an ice chest with ice. The samples was shipped to EMAX analytical laboratory in Torrance, California under proper chain -of -custody procedures for VOC analysis by U.S. Environmental Protection Agency (EPA) Method 8260B. On June 29, 2006, each gas -migration monitoring probe and each extraction well was measured for methane, oxygen, and carbon dioxide using a handheld portable landfill gas monitor. These measurements were recorded in a field log book. RESULTS Groundwater. VOC constituents were not detected above the analytical laboratory reporting limits in the groundwater sample collected from MW -l. The following VOC constituents were detected in the groundwater sample collected from MW -2: acetone at 12 micrograms per liter (gg/L); carbon disulfide at 0.81J gg/L; and cis-1,2-dichloroethene at 0.66J gg/L. Only chloroform was detected at 1.7 gg/L in the groundwater sample collected from MW -3. Acetone, carbon disulfide, and chloroform are known to be common laboratory contaminants. Of the four reported VOC constituents, primary maximum contaminant levels (MCLs) are established for two (cis-1,2-dichloroethene at 70 gg/L by the EPA and 6 gg/L by the California Department of Health Services [DHS] and chloroform at 80 gg/L by EPA and 100 gg/L by DHS). Of the remaining two constituents, a California State Action Level for Drinking Water (CSALDW) is established by DHS for only carbon disulfide, at 160 gg/L. For the remaining constituent, acetone, the Taste and Odor Threshold (TOT) value is established at 20,000 gg/L. Analytical results for each well are summarized in Table 1. The analytical report is provided as Attachment 4. Soil Vapor. The methane concentrations in VW -1, VW -2, VW -3, VW -7S, VW -7D, VW -8S, VW -8D, VW -9, and VW -10 were 0 percent. The methane concentrations in VW4, VW -5S, VW -5D, VW -6S, VW -6D, EW -1, and EW -2 were 12.0%, 12.5%, 5.9%, 13.1%, 5.4%, 23.1% and 5.5%, respectively. The K:\Wprocess\25532\WorldEnterprise\Quarterly Rpt\2QO6\CovLtrRpcdoc