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Mr. Lawrence Stefani October 7, 2003 Page 2 If the methane gas component of LFG is allowed to accumulate in a confined area (i.e., utility lines, irrigation valve boxes, vaults, basements, wall spaces, etc.) and is exposed to an ignition source, it can be explosive at concentrations between 5 and 15 percent by volume. At higher concentrations, methane gas is flammable. However, the presence of methane gas in site soil does not mean there is an immediate threat of explosion because flames cannot typically propagate through soil. Operation Criteria The most current Permits to Construct/Operate dated July 22, 2002 and October 8, 2002, issued by the San Joaquin Valley Unified Air Pollution Control District (SYVUAPCD) delineates several main operational criteria for the subject system. This operational criteria states that flare exit gas temperature be maintained at a minimum of 1400 degrees Fahrenheit during system operation. In addition the systems are to be operated to maintain compliance with SJVUAPCD Title V and Rule 4642 requirements. State California Code of Regulations (CCR Title 27) requires that solid waste disposal site owners/operators implement LFG control or monitoring provisions to ensure that methane gas concentrations in soil at the property line do not exceed the lower explosive limit (LEL, or 5 percent by volume) and that interiors of on-site structures do not exceed 1.25 percent methane by volume in air. Gas Testing Testing for methane gas (the combustible component of LFG), oxygen gas, carbon dioxide gas, pressure, and temperature was performed using a Landtec Gem-500 Gas Analyzer or comparable unit. This instrument measures combustible gas concentrations in air directly on either of two scales: the first as percent by volume of the lower explosive limit (LEL) of methane gas in air(5 percent); the second as percent by volume (0 to 100 percent) in the gas sampled. Instrument calibration forms are attached to this report. LFG Monitoring Probes In accordance with the approved testing schedule,LFG Monitoring Probes (MP) are to be tested quarterly or when methane gas concentrations detected exceed 5 percent by volume or as requested by the client. On September 9, 2003, all LFG monitoring probes were tested for the presence of LFG. Results indicated that no methane gas concentrations in excess of 5 percent by volume was detected at any location tested (see Table 1) with the exception of LFG Monitoring Probe No. MP-9 (up to 54.0). SCS understands that additional extraction wells and expansion of the collection is currently being performed by others, to help decrease the observed elevated methane gas concentrations at MP-9.