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Mr. Don Litchfield April 9, 2010 Page 3 LFG Monitoring Probe Nos. GP-11M, GP-11 S and.GP-12S (up to 63.9%by volume). SCS will continue to monitor these locations on a weekly basis and all probes quarterly as directed by the Client. The next complete quarterly probe monitoring is due by the end of June 2010, or as directed by the client. As previously reported in January 2010, SCS performed monitoring of Temporary Gas Probe Nos. TGP-01 through TGP-39, as directed by the Client. On March 12,2010, SCS performed monitoring of Temporary Gas Probe Nos. TGP-09, TGP-11 and TGP-12. Results of the quarterly monitoring indicated that methane gas concentrations in excess of 5 percent by volume were detected at many of the location tested(up to 70.8%by volume). Test Results from the March 2010 monitoring indicated methane gas concentrations up to 64.2%by volume. Note, that these probes are intended for evaluation purposes only and are not compliance locations. SCS will complete the next quarterly monitoring by the end of June 2010. ON-SITE STRUCTURE MONITORING In accordance with the approved testing schedule,the interiors of the on-site structures are to be tested quarterly. On March 26, 2010, SCS performed the required testing. Results indicated that no methane gas was detected at any location tested(Table IA). The results were included in our first quarter 2010 probe and structure monitoring report. The next quarterly interior structure monitoring is due by the end of June 2010. LFG EXTRACTION WELL 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 overpull or underpull condition). Overpull 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. During 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 monthly testing of LFG extraction wells performed on March 4, 5, 11, 12, 22, 23, 24, 25 and 26, 2010, (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 minimum 1400 degrees Fahrenheit flare exit gas temperature)at the BFS, to help maintain methane gas concentrations at the perimeter and temporary monitoring probes to below the LEL and maintain compliance with the new Title V permit wellhead conditions. SCS will