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URS Mr. Robert McClellon July 14, 2005 Page 2 Landfill Gas Extraction Pilot Testing Methodology To complete the pilot test, a positive displacement blower will be connected to the two 2-inch diameter wells(see Figure 1 —Site Plan). Landfill gas extraction rates are expected to be up to 250 standard cubic feet per minute (scfm). The extracted landfill gas will be treated using a stand-alone, completely protected thermal oxidizer unit, with automatic shutdown features. The extraction well flow rate and vacuum will be measured at regular intervals to allow for proper sizing of a remediation system. The extracted vapors will be sampled and analyzed for volatile organic compounds (VOCs) as well as for typical landfill gas constituents (i.e.,methane,oxygen, and carbon dioxide). Test Protocol The system selected for the pilot test will use the following(or similar equipment): • Positive displacement blower capable of extracting 250 scfm at 8 inches of mercury (in. Hg) vacuum; • 7.5 horsepower(Hp)motor; • Trailer-mounted thermal oxidizer with a chart recorder; • 25 kilowatt(kW)propane-fired electric generator(for the blower motor and controls); and • 150-gallon knockout pot for landfill gas condensate. Propane also will be used as supplemental fuel for the oxidizer. The following pilot test procedures will be followed. • Landfill gas flow rate step tests will be performed at each extraction well to establish the gas-flow capacities.The step tests are expected to last less than 2 hours at each well. • Sustained tests will be performed at each extraction well to verify the stable methane concentra- tions.The sustained tests are expected to last approximately 44 hours at each well. • Extraction well flow rate optimization will be performed following the sustained tests to establish the most efficient simultaneous operation of the two landfill gas extraction wells. Optimization is expected to last approximately 8 hours on the final (fifth)day of the pilot test. Flow rate and vacuum will be measured as follows. • During the step tests, the extraction well flow rate and vacuum will be recorded as frequently as required to assess the behavior of the extraction well (e.g.,every 5 minutes). • During the sustained tests and optimization, the extraction well flow rate and vacuum will be recorded every half-hour until stable. Following stabilization, readings will be taken approximately every hour. The vacuum induced at the site monitoring wells will be recorded every two hours. K:\Wprocess\25532\WorldEnterprise\GWMPIR\Ietter.doc