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Draft Supplemental Environmental Impact Report Page IV.G-12 Forward Inc. Landfill 2018 Expansion Project The well MW-17 is the only one of the three wells to be decommissioned that has a history of VOC hydrochemistry.In Q1-2018 the Well MW-17 showed carbon tetrachloride and chloroform above reporting limits, and trichlorfluromethane at trace concentrations. As discussed previously, there are two groundwater monitoring programs for the Forward Landfill, one for the Forward Unit and the other for the Austin Road Unit. The Forward Landfill, initiated in 1973,has had a groundwater-monitoring program since 1977. In accordance with WDR Order R5-20014-0006, there are 33 monitoring wells (including well pairs), 15 associated with the Forward Unit, and 18 associated with the Austin Road Unit. Additional wells have been added to the monitoring program since the WDR Order was issued, however the WDR Order has not yet been modified to reflect these changes. The additional wells are (or will be in the case of the newly installed wells)sampled and reported in quarterly monitoring reports. Both landfill units also have water supply wells. The monitoring and supply well locations are depicted on Figure IV.G-1. The existing monitoring system meets the requirements of the landfill's Detection Monitoring Plan(DMP)for groundwater monitoring, and the CAP for groundwater impact. Austin Road Unit The main area of groundwater impact is downgradient of the landfill units, in the California Dept. of Corrections and Rehabilitation (CDCR)property. This facility historically had its own groundwater production wells which pulled the landfill-related plume downgradient towards it until 2011, when well production ceased and municipal water was piped into the facility. The RWQCB has required Forward to evaluate the offsite plume, including vertical sampling and evaluation of wells at Forward Landfill. In April 2018 monitoring wells were completed by GLA in compliance with the Cleanup and Abatement Order (CAO)No. R5-2017-0703, Requirement 4.A. This was done based on the approval of April 28, 2017 West Side Monitoring Well Installation Workplan, and September 15, 2016 Northside Monitoring Well Workplan issued by the RWQCB. Each vertical profile well was drilled to a total depth of 500 bgs and discreet groundwater samples were collected at first water(71 feet)and within observed water- bearing sands depths of 90, 100, 168, and 380 feet bgs. No volatile organic compounds were detected in the groundwater first encounter water or below. Groundwater quality is summarized in the quarterly and annual monitoring reports. Reports are submitted to the RWQCB and DTSC and can be viewed on the California Geotracker system (http://geotracker.swrcb.ca.gov/). The groundwater-monitoring system is designed to detect the presence of contaminants in groundwater by analyzing groundwater chemistry at point-of-compliance wells. Chlorinated hydrocarbons, also referred to as volatile organic compounds, are typically the chemicals of concern that are detected at landfills. Numerous studies and groundwater monitoring events have been completed. The Forward Landfill extraction and treatment system discharges the treated groundwater to an infiltration basin. However,they recently had a violation cited by the RWQCB (May,2018). The treatment and discharge of treated groundwater at the Forward Landfill in San Joaquin County is regulated by Waste Discharger Requirements (WDRs)Order R5-2003-0080. The RWQCB noted that the VOC concentrations reported in Q4-2018 and Q1-2018 are a violation of