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Draft Supplemental Environmental Impact Report Page VIII-63 Forward Inc.Landfill 2018 Expansion Project contaminants to groundwater. These measures include LFG extraction and delivery to the on-site cogeneration plant.The existing LFG extraction wells and the LFG extraction system will be expanded to include LFG extraction wells in the proposed northern and southern expansion area to prevent any LFG impacts to groundwater. As far as potential contamination of surface water bodies such as Littlejohn's Creek,the base of all WMUs are below the elevation of the creek and, as discussed in the preceding paragraphs,the liner and LCRS in these WMUs is protective of underlying groundwater.If any spills were to occur outside a lined WMU,the area would be remediated in accordance with Forward's Emergency Action Plan contained within Forward's Site Health and Safety Program (Forward Landfill Joint Technical Document, SWT,January 2018).Also,all surface water runoff from operating areas would be routed to onsite sedimentation and stormwater ponds and away from the creek.Therefore,the potential for a spill affecting the function or habitat of the creek is considered less than significant. J-1c. Please see response to Item J-1A J-2.The regional groundwater gradient surrounding the Forward Landfill has historically been and continues to flow to the north and northeast. Locally,the groundwater flow direction within the southern half of the Forward site,began to shift from the regional northeastern flow direction to a more southeasterly flow direction, beginning in 2011. It is believed that the local southeasterly gradient is associated with pumping of agricultural wells south of the Forward Landfill (Forward Landfill Quarterly Groundwater Monitoring Report,Third Quarter 2018,GLA, October 2018). There are five agricultural wells south of the Forward Landfill. The closest is the �i Brocchini well on the southwest corner of Forward Landfill property, on the north side of Lttlejohns Creek.Four other agricultural wells,8262, 101744, 097907 and 6840, are located between 800 and 2,600 feet south of Forward Landfill. These wells are screened from between 130 feet bgs and 376 feet bgs and produce a total of approximately 1,000 gpm. The closest Brocchini well is screened from 276 to 376 feet bgs. The only VOCs measured relatively consistently at quantifiable concentrations (above estimated trace concentrations)in groundwater samples recently have been in the two Forward Unit wells MW-17 on the northwest corner, and MW-16 on the northeast corner. Both wells monitor the uppermost water-bearing zone. The nearest of these wells to the LaForge wells is well MW-16.The measured VOCs in groundwater samples from this well have not exceeded either state-or federally established Maximum Contaminant Levels(MCLs [public drinking water standards]). MCLs are conservative limits established by US EPA and the State of California for acceptable public drinking water. Groundwater contaminants below MCLs are therefore considered safe for drinking by the public. Since the localized change in flow direction was identified,no VOCs have been detected in groundwater samples from wells MW-22 and MW-23R, located downgradient(south)of the landfill, along the southern property boundary.