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U Quarterly Progress Report - Second Quarter 2017 Austin Road Unit, Forward Landfill Remediation System Operations and Performance Evaluation of Individual Extraction Points CAO Task 6.a indicates that Quarterly Progress Reports shall include information on remedial system operation and performance during the relevant quarter. The CAO does not provide a definition of the 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. The Groundwater Treatment Facility (GTF) 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 GTF includes four groundwater extraction 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 GTF during the period of April 1 through June 30, 2017. The system monitoring logs from Del - Tech for the second quarter 2017 are included in Attachment A. Del -Tech records indicate that the groundwater extraction and treatment system experienced the following maintenance issues and periods of downtime during the second quarter 2017: • April 28, 2017: Del -Tech reported that well EW -3R was off-line and the breaker would not reset. Del -Tech pulled the pump and determined that the pump motor had failed. GLA notified the CVRWQCB of the pump failure. A replacement pump was installed on June 10, 2017. Based on analytical laboratory testing results from March 31, 2017, the influent to the groundwater treatment system contained 2.51 pg/L of VOCs (excluding acetone, a suspected laboratory contaminant). Based on totalizing flow meter readings from Del -Tech, an estimated 15.9 million gallons of extracted groundwater was treated during the second quarter 2017, yielding approximately 0.23 pounds of VOCs removed during this period. Treated effluent discharged into the infiltration pond contained trace concentrations of up to three VOCs in the monthly effluent samples. In addition, cis-1,2-dichloroethene and tetra chloroethene were measured above the practical quantitation limit during the June sampling event. Total VOC concentrations in the effluent ranged from 0.6 µg/L to 1.85 µg/L during the monitoring period. Landfill Gas Collection and Destruction System As of January 2017, the landfill gas collection and destruction system servicing the Austin Road Unit at the Forward Landfill consists of 129 landfill gas extraction wells, according to 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, Inc. (SCS) records information such Project No. S017.1030 I Quarterly Progress Report - Second Quarter 2017 2