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Quarterly Progress Report — Third Quarter 2014 Austin Unit. Forward Landfill Page 2 term "remedial system". Forward, Inc. interprets the term to include the groundwater extraction and treatment system, along with the landfill gas collection and destruction system. Landfill gas collection and destruction provides source control. Groundwater extraction and treatment provides remediation to impacted groundwater. Information relevant to each of the remediation systems is provided below. As described in the CAO, the evaluation of individual extraction points applies to both groundwater and landfill gas extraction points. Groundwater Extraction and Treatment System The groundwater extraction and treatment system includes four groundwater recovery wells (EW -1, EW -2, EW -3R and EW -4), an above -ground air stripper system, and an infiltration basin luted north of the landfill. Each of these components was previously approved by the RWQCB. Del -Tech Geotechnical Support Services, Inc. (Del -Tech) performed operations and maintenance on the groundwater extraction and treatment system during the period of July 1 through September 30, 2014. The system monitoring logs from Del -Tech for the third quarter 2014 are attached. Del -Tech records indicate that the groundwater extraction and treatment system experienced the following maintenance issues and periods of downtime during the third quarter 2014: • July 15, 2014: It was observed that recovery wells EW -3R and EW -4 were offline, possibly due to power outages. The wells were reset by Del -Tech and restored to operation. • September 8, 2014: It was observed that recovery wells EW -3R and EW4 were offline, possibly due to power outages. The wells were reset by Del -Tech and restored to operation. Based on analytical laboratory testing results from August 29, 2014, the influent to the groundwater treatment system contained 5.97 ug/L of VOCs. Based on totalizing flow meter readings from Del - Tech, an estimated 19.7 million gallons of extracted groundwater were treated from July 1 through September 30, 2014, yielding approximately 0.49 pounds of VOCs removed during the noted period. There were no VOCs detected above their reporting limits (RLs) in the most recent treatment system eluent sample for which results are available, collected on August 29, 2014. Landfill Gas Collection and Destruction System The landfill gas collection and destruction system at the Austin Road Unit consists of 194 gas extraction wells, according to information provided by SCS Field Services, Inc. Collected landfill gas is routed to Flare A-2 for thermal destruction, with Flare A-1 serving as a back-up flare. On a weekly basis SCS Field Services records information such as methane gas concentration (percent by volume), oxygen concentration (percent by volume), carbon dioxide concentration (percent by volume), balance gas (percent by volume), flow rate (scfin), inlet pressure, outlet pressure, gas temperature at the inlet and outlet, and equivalent British Thermal Units (BTUs) consumed. The landfill gas collection and destruction system undergoes periodic maintenance to re -balance the collection vacuums to produce the highest percentage of landfill gas (e.g., methane) and to minimize the collection of oxygen.