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Ms. Christina Carbajal July 19,2006 Page 3 Also, on June 14, 19, and 29,2006, SCS performed testing of subsurface evaluation monitoring point ETGP-09 as requested by the Client(see Table 5). These test results are intended for evaluation purposes to assist in LFG extraction well adjustments. Finally,on June 1.4,2006, SCS performed monthly monitoring of Temporary Gas Probes, defined as TGP-01 through TGP-39, as directed.by the Client. Results of this monitoring indicated that methane gas concentrations in excess of the LEL were detected at several locations tested (up to 58.4 percent by volume). However,during their reporting period,SCS has continued to observe a fluctuating tread in the detected methane gas concentration.Note,that these probes are intended for evaluation purposes only and are not compliance locations(see Table 1). On-Site Structure Iulonitoring ln,accordance with the approved testing schedule,the interior of the on-site structures are to be tested quarterly. On June 6, 2006, SCS performed the required testing and included these results in our second quarter 2006 probe and structure monitoring report. The next quarterly interior structure monitoring is due by the end of September 2006. LFG Extraction Well1 Testing System,adjustments are required whenever an extraction well exhibits an,unacceptable change in methane and/or oxygen gas concentration (which could be due to an ovespul.l or underpull conditio.-a). Overpul,l occurs when the extraction rate of a particular extraction well exceeds that of the LFG generation rate"within the radius of influence of the well. luring this overpull condition, air can be drawn through the ground surface to the extraction well and then ultimately be injected into the flare. if an excessive overpull condition is allowed to continue for a long period, a significant drop in the methane gas content of the LFG and/or a subsurface landfill fire could Occur. Underpull occurs when the extraction rate of a particular extraction well is less than the generation rate within the radius of influence of the well. This condition could result in off-site subsurface LFG migration and/or surface emissions. Results of moAth.ly testing of LFG extraction wells performed on June 6, 14 and 29,2006(see Table 2)indicate that several,extraction wells exhibited an overpull and/or underpull.condition. These conditions are necessary to maintain operational criteria(e.g. maintain a mi.nirnum 1400 degrees Fahrenheit flare exit gas temperature)at the BFS and to help mainta3.n/decrease methane gas concentrations at perimeter monitoring probes to below the LEL. SCS will continue to monitor and adjust all LFG extraction wells to minimize the amount of overpulI while maintaining operational criteria.