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I URS Mr. Robert McClellon July 13, 2007 Page 2 groundwater,three groundwater monitoring wells were installed at the site on June 12, 2006. Following the installation of the groundwater monitoring wells, groundwater samples have been collected and analyzed quarterly for VOCs. In a meeting on May 24,2007,Mr. Ross Atkinson of the Regional Water Quality Control Board(RWQCB)concurred with the recommendation in the Quarterly Monitoring Report dated April 30, 2007 to suspend the groundwater monitoring activities for VOCs. As per Mr. Atkinson request, groundwater samples have been collected and analyzed for metals and general minerals(only total dissolved solids [TDS] after the first event)since the fourth quarter of 2006. FIELD ACTIVITIES During the second quarter of 2007, landfill gas concentrations were measured within the probes, extraction wells,and passive vents every two to three weeks. The quarterly groundwater monitoring activities were completed on June 14, 2007. Each gas-migration monitoring probe, each extraction well,and each passive vent was measured for methane,oxygen,and carbon dioxide using a handheld portable landfill gas monitor. These measure- ments were recorded in a field log book. The groundwater samples were collected from the three monitoring wells using the following procedures: • The water level from each monitoring well was measured using an electronic water level sounder. • Prior to groundwater sample collection, each well was purged using a bailer. During purging, groundwater parameters(pH,temperature,and conductivity)were recorded on the Monitoring Well Sampling Log form(Attachment 1)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 dissolved metals(CAM 17)by U.S. Environmental Protection Agency(EPA) Method 6010/6020/7470 and TDS by EPA Method 160.1. RESULTS Soil Vapor. The methane concentrations measured during the quarter in VW-1,VW-2,VW-3,VW-4, VW-7S,VW-7D,VW-8S,VW-8D,VW-9, and VW-10 were 0 percent. The methane concentration for the remaining vapor probes ranged from 0.1%to 0.8% in VW-5 S, from 0.8%to 1.2% in VW-5D, from 1.3%to 4.0% in VW-6S, from 0.7%to 1.4% in VW-6D. K:\Wprocess\25532\WorldEnterprise\Quarterly Rpt\2Q07\CovLtrRpt.doc