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Corral Hollow LFG System Audit and Upgrade Report ' minute (rpm). The vacuum applied to the wellfield can be adjusted by the inlet and outlet valves of each blower; however, the flow rate to the flare station from the LFG well field t is controlled by adjustments at each well. Each blower is switched from primary to secondary use as necessary so that one blower is available as backup in case of breakdown or servicing of a blower is required. ' Based on County records, the flow rate from the LFG well field has decreased over time (Table 1). During our October 2013 field investigation (Appendix A), LFG flow and quality ' was measured at 98 scfm with a methane content of 19.8% v/v. Please note that these data include contributions from soil gas captured by the two perimeter extraction wells. Table 1 . Corral Hollow Landfill Capture Gas Data ' Year Flow, scfm methane •. v/v Heat Rate, mm BTU/hr 2011 132 20.1 1.61 , 2012 146 18.6 1.65 2013 (Jan-July) 124 20.6 1.55 2013(Oct) 98 19.8 1.18 %v/v = percent methane by volume ' scfm = LFG flow,standard cubic feet per minute mm Btu/hr =million British thermal units per hour , SCADA System— Remote Blower/Flare Operation Status Monitoring The blower/flare station is equipped with supervisory control and data acquisition (SCADA) ' sensors and controls that allow the County to remotely monitor flare station operating status from County offices. The system transmits the following operating data: blower on/off status; LFG ' flow rate; flare combustion temperature; condensate injection pump on/off status; and approximate condensate tank liquid level. During normal business hours, County personnel confirm that the gas handling systems are properly operating. If any operating problems are ' identified, personnel can be dispatched to the Site to troubleshoot and restore system operation. In addition, the flare station is provided with an automatic alarm alert feature. This feature ' automatically notifies the County office in case of unscheduled shutdown. Landfill Gas Migration Monitoring Network ' A network of perimeter landfill gas migration monitoring wells (gas probes), designed by a registered civil engineer, have been installed in native soils outside the landfill footprint to monitor subsurface LFG migration in accordance with 27 CCR. A total of 9 monitoring wells ' (GW-1 through GW-9), are installed at or near the property boundary. Each well is fitted with 6 December 2013