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Draft Supplemental Environmental Impact Report Page VIII-60 Forward Inc.Landfill 2018 Expansion Project many monitoring wells.Most recently,the western portion of the plume was delineated as described in the Forward Landfill-Well Installation Report Evaluation Monitoring Program-West Side report by Geo-Logic Associates (GLA 2018). Additional assessment activities are in progress and will be completed in accordance with CVRWQCB oversight in 2019. Concurrently, remediation activities are in progress to restore beneficial use conditions to the impacted groundwater.A groundwater extraction and treatment system (GTS)is operated at the point of compliance (northern boundary of Austin Road Unit).The GTS is operated in accordance with the CAO and with CVRWQCB Waste Discharge Requirements(WDRs)for the site. Upgrades and optimization of the GTS are in progress and will be implemented with concurrence from the CVRWQCB. Additionally, work is in progress to design a remedy for VOC impacts downgradient of the point of compliance. The downgradient remediation plan is required by the CAO and will be submitted to the CVRWQCB in a Revised Engineering Feasibility Study in 2019.These activities, however,are not a condition of, or related to,the need to monitor for the proposed project waste cell additions to the south of this area. J-1b. An additional 8.7 acres of permitted landfill acreage is proposed in the NE corner of the existing landfill. Landfilling is already permitted in the area of the landfill south of the South Creek,however,the proposed relocation of the creek would create an additional 8.6 landfill acres. This new acreage is surrounded by other lined cells of the Forward Landfill.In total, approximately 17.3 acres would be added to the overall 388 acres of existing permitted landfill footprint,resulting in an approximately 4.5 percent increase in the overall landfill footprint. Again,unlike the unlined Austin Road Landfill, the additional landfill acreage in the proposed Project will be designed, constructed and operated in accordance with federal and California landfill modern regulatory design standards, all of which will be subject to the prior approval and oversight of the CVRWQCB. As described in the SEIR Project Description,the new landfill cells will be lined with a system designed to accommodate the geologic and hydrogeologic conditions at the site and include a composite lining system composed of two-feet of clay with a permeability less than 1 x 10-7 cm/sec and overlain with a 60-mil HDPE geomembrane.The composite lining system will be overlain by a leachate collection and removal system (LCRS)consisting of a cushion geotextile, 1-ft thick granular drainage layer(including a network of perforated HDPE pipes),another geotextile, and a 1-ft thick soil operations layer. The LCRS drains to a composite-lined sump located in the low spot of the WMU. Leachate is routinely pumped and removed from the sump to minimize the leachate head (hydraulic pressure)on the composite lining system. Leachate is disposed in the onsite Class II double-composite-lined leachate evaporation ponds. The LCRS is designed using very conservative estimates of precipitation and infiltration based on local climatological data. The redundant perforated pipeline and gravel blanket collection systems would provide additional factors of safety to ensure against i