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Quarterly Progress Report — Second Quarter 2015 Austin Unit. Forward Landfill Page2 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 located 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 April 1 through June 30, 2015. The system monitoring logs from Del -Tech for the second quarter 2015 are attached. Del -Tech records indicate that the groundwater extraction and treatment system experienced the following maintenance issues and/or periods of downtime during the second quarter 2015: • April 8, 2015: It was observed that all recovery wells and the air stripper were online due to an apparent power failure. The system was restored to operation by Del -Tech ® • April 22, 2015: It was observed that recovery well EW -2 was offline due to an apparent power failure. The well was reset by Del -Tech and restored to operation. • May 12, 2015: It was observed that recovery well EW -2 was offline due to a failed pump motor. The pump motor is scheduled for replacement the week of July 13, 2015. • May 26 — June 1, 2015: All recovery wells and the air stripper were immediately switched offline due to breaks in main effluent and influent lines caused by contractor heavy equipment. Both lines were repaired and the system was restored to operation on June 1, 2015. Based on analytical laboratory testing results from April 8, 2015, the influent to the groundwater treatment system contained 9.68 ug/L of VOCs. Based on totalizing flow meter readings from Del - Tech, an estimated 11 million gallons of extracted groundwater were treated during the second quarter 2015, yielding approximately 0.89 pounds of VOCs removed during this period. There were no VOCs detected above their reporting limits (RLs) in the most recent treatment system effluent sample for which results are available, collected on June 16, 2015. Landfill Gas Collection and Destruction System The landfill gas collection and destruction system servicing the Austin Road Unit at the Forward Landfill consists of 107 landfill gas extraction wells, according to the 2015 GCCS Improvements Plans prepared by Cornerstone Environmental. 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 :7