Laserfiche WebLink
4683 Chabot Dr., #200, Pleasanton, CA 94588 | 925-426-0080 <br />Environmental Consultants & Contractors <br />July 13, 2023 <br />Project No. 01221044.07 <br />Mr. Brendan Kenny <br />Central Valley Regional Water Quality Control Board <br />11020 Sun Center Drive <br />Rancho Cordova, CA 95670 <br />Subject: SECOND QUARTER 2023 LFG GCCS UPDATE <br />FORWARD LANDFILL <br />MANTECA, CALIFORNIA 95336 <br />Dear Mr. Kenny: <br />On behalf of Republic Services and Forward, Inc. (Forward), SCS Engineers (SCS) is pleased to <br />submit the Second Quarter 2023 Corrective Action Program Update for the landfill gas (LFG) <br />collection and control system (GCCS) at the Forward Landfill (Landfill or Site), located in Manteca, <br />California. Information herein is being provided to the Central Valley Regional Water Quality Control <br />Board (CVRWQCB) as part of the directives set forth in Cleanup and Abatement Order (CAO) R5- <br />2017-0703 (Order). Please see the details for compliance and operations below. <br />ORDER COMPLIANCE <br />The following is a summary of the second quarter 2023 activities performed as they pertain to the <br />performance and improvements of the GCCS: <br />•Continued monitoring of twelve (12) perimeter gas monitoring probes. The current probe <br />network subject to the CAO includes wells GP-1A through GP-6A, and GP-10 through GP-15. <br />All CAO probes were monitored on May 11, 2023 as part of SCS Field Services (SCSFS) site- <br />wide LFG monitoring and onsite structure testing event. Note that testing, monitoring <br />protocols, and reporting were performed in general conformance with Title 27 California Code <br />of Regulations (CCR) Article 6. The monitoring results for the CAO probes are presented in <br />attached Table 1. <br />•Per the Order, based on the second quarter monitoring results, probe intervals GP-10D, <br />GP-10M, and GP-10S will require annual TO-15 sampling due to a detection of methane <br />greater than 1 percent of 61.5, 60.3, and 60 percent, respectively. Probes GP-11D, GP-11M, <br />GP-11S, GP-12D, GP-12M, GP-13D, GP-14M, and GP-15M will require annual TO-15 sampling <br />due to VOC concentrations detected above 10 parts per billion by volume (ppbv). The TO-15 <br />sampling of these probes is conducted on an annual basis and will be sampled later in the <br />year, in conformance with the Order. <br />COMPLIANCE TESTING INSTRUMENTATION AND METHODS <br />Testing for methane gas, oxygen gas, carbon dioxide gas and pressure was performed using a <br />Landtec GEM-5000 Gas Analyzer calibrated to methane gas. The instrument measures combustible