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Quarterly Progress Report — First Quarter 2015 . Austin Unit Forward Landfill Pam 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 EW4), 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 January 1 through March 31, 2015. The system monitoring logs from Del -Tech for the first 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 fust quarter 2015: • February 10, 2015: It was observed that recovery well EW -3R was offline due to an apparent power failure. The well was reset by Del -Tech and restored to operation. • March 30, 2015: It was observed that all recovery wells and the air stripper were offline due to an apparent power failure. The system was restored to operation by Del -Tech. 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 22.7 million gallons of extracted groundwater were treated during the first quarter 2015, yielding approximately 1. 13 pounds of VOCs removed during this 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 March 20, 2014. 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 -I 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.