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Quarterly Progress Report — Third Quarter 2015 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 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 July 1 through September 30, 2015. The system monitoring logs from Del -Tech for the third 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 third quarter 2015: • July 8, 2015: Recovery well EW -2 was offline due to an apparent failed pump motor. This issue had first been observed on June 16, 2015. Maintenance was completed on EW -2 and the well was restored to operation on July 18, 2015. • July 21, 2015: It was observed that recovery well EW -1 had a pump encrusted with precipitates / deposits that were inhibiting uptake of groundwater. The well was disassembled, cleaned, and reassembled by Del -Tech and restored to operation on July 25, 2015. • July 27, 2015: It was observed that recovery well EW -3R was offline due to a failed pump motor. Maintenance was completed on EW -3R and the well was restored to operation on August 12, 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 15.9 million gallons of extracted groundwater were treated during the third quarter 2015, yielding approximately 1.29 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 volume), carbon dioxide concentration (percent by volume), balance gas (percent by volume), flow rate 0