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Mr. Don Litchfield October 8, 2010 Page 3 concentrations in excess of 5 percent by volume were detected at any location tested(Table 1), with the exceptions of LFG Monitoring Probe Nos. GP-IOS, GP-I ID, GP-11M and GP-11S (up to 57.6%by volume). SCS will continue to monitor Perimeter Probes defined as Nos. GP-09, GP-10, GP-11 and GP-12 on a weekly basis and all probes quarterly as directed by the Client. SCS understands that the probe network is under review by the CIWMB to enable relocation of the probes to the property boundary. The next complete quarterly probe monitoring is due by the end of December 2010, or as directed by the client. In August 2010, SCS performed monitoring of Temporary Gas Probe Nos. TGP-01 through TGP-39, as directed by the Client. Additionally, on September 1, 2010, SCS performed monitoring of TGP-38B (Table 1). 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 57.5%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 December 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 September 14, 2010, SCS performed the required testing for the third quarter 2010. Results indicated that no methane gas was detected at any location tested. The results were included in our third quarter 2010 probe and structure monitoring report. The next quarterly interior structure monitoring is due by the end of December 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 September 1, 3, 7, 14, 17, 18, 20 and 21, 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