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Draft Supplemental Environmental Impact Report Page VIII-62 Forward Inc.Landfill 2018 Expansion Project layer, a CQA Report is prepared following construction and submitted to the CVRWQCB for approval prior to any waste being disposed in the unit. In addition to the design and construction of the WMUs,Forward's operating and monitoring programs mitigate potential leakage from lined landfill units.These include: • Leachate collection, management, and monitoring • Groundwater monitoring • Surface water drainage management and monitoring systems • Landfill gas collection systems and monitoring programs • Load checking and Hazardous Waste Exclusion Program (HWEP) • Daily,intermediate, and final soil covers As mentioned above,to monitor the landfill for leakage from the liner system to the vadose zone,pan lysimeters are installed beneath the proposed liner system sump to monitor for the presence of leachate. The sump is located at the lowest and,therefore, most critical part of the WMU, as all leachate flows to and is collected and removed from this point.A pan lysimeter is essentially a secondary sump (or depression) constructed under the primary sump.The pan lysimeter is lined with a composite liner system and filled with permeable material,such as gravel.A riser pipe allows access to the pan A lysimeter to detect, sample, and remove liquids within the pan lysimeter and allows for a secondary containment system beneath the primary sump. During the operational life of the landfill, and through closure and the post-closure maintenance period, the perimeter of the site adjacent to the proposed expansion areas would also include additional groundwater monitoring wells. Perimeter soil-pore gas monitoring probes would also be constructed around each of the expansion areas and monitored for the presence of landfill gas. These proposed groundwater monitoring wells, lysimeters,and gas probes would be monitored quarterly and reported to the CVRWQCB in accordance with Title 27 regulations. In the highly unlikely event that groundwater contamination from the landfill is identified, the CVRWQCB would be immediately notified, and they would require additional monitoring, evaluation, groundwater remediation, or other measures to be implemented to minimize the impact on the environment, and ensure that beneficial uses of the local groundwater supply are not compromised. The groundwater and leachate chemistry trends identified throughout the active life of the landfill and post- closure maintenance period would provide guidance to the RWQCB as to whether additional groundwater monitoring or corrective actions are necessary beyond the required 30-year post-closure period. The existing groundwater remediation infrastructure for the Austin Road Unit could be utilized to treat potential contamination from the northeast expansion area given the proximity and the local groundwater flow direction in that part of the site. Forward would also implement source-control measures to capture landfill gas (LFG)in the additional lined expansion areas to prevent the potential conveyance of r