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Robert McClellon August 24, 2000 Page 2 This violation was cited in conjunction with the odor of landfill gas being emitted near one of the blowers on the gas collection system. The County is taking measures to prevent"escape" of gas from the blowers, but we do not feel that this is resulting in a lack of landfill gas control, and should not be a violation under the stated section. The County has implemented a system for maintaining landfill gas control and therefore we believe that we are not in violation. The odor coming from the blower is similar to that from the working face of an active landfill and does not demonstrate inability to control gas at the site perimeter. Gas System History The landfill gas flare system has been operating for approximately four years. During the winter and spring of 1999, the County experienced problems with the landfill gas collection system. Due to differential settlement of the landfill and the high amount of rainfall during the season, several water blockages were discovered in the header pipes around the outside of the landfill. The County worked for several months to track down and repair all affected areas of the collection system. As a result of the water blockages, the gas collection system was unable to operate efficiently and there was a loss of vacuum to the northern areas of the landfill. During this time, high levels of methane were detected in several gas probes around the perimeter of the property. In the summer of 1999, the water blockages were cleared up, but it was determined that there was still insufficient vacuum to the northern half of the landfill to adequately control landfill gas migration. At that time, the County was consulting with the system designer to modify the gas collection system to maximize the amount of vacuum affecting the site. Prior to implementation of corrective action, the system was managed in a way to direct more of the available vacuum to the north half of the site by greatly reducing the amount of vacuum used by the south half. This practice showed a reduction of gas migration, but there was still migration detected in one perimeter well during the Fourth Quarter 1999 Monitoring Event. It was determined that by reconfiguring the blowers to operate together, the maximum amount of vacuum could be distributed to the gas collection system. In December of 1999, the blowers in the flare station were reconfigured to run in series, and large amounts of vacuum were detected at all areas of the landfill. The system ran this way for approximately four months and no exceedences were shown in any probe during the First Quarter Monitoring Event for 2000. In conjunction with the recent repairs to the pipe system and the reconfiguration of the blowers, the County showed that the gas system could effectively control landfill gas migration. In March 2000, several malfunctions were detected at the flare station. We believe that an electrical spike caused damage to the monitoring equipment and the blowers. During the next three months, the County sought the assistance of several electricians to determine the damage and correct the problems. It was determined that the flare high temperature controller and high