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Forward Landfill 9 15 August 2023 GeoTracker No : L10008827999 Report Conclusions and Recommendations The report states , "Forward, Inc. has demonstrated that the improvements to the groundwater extraction and treatment system have provided complete capture of VOCs at the Landfill's POC, meeting one of the RAOs stipulated in the CAO . Concentrations of PCE in the shallow and intermediate zones downgradient of the POC slightly exceed the MCL of 5 Ng/L, and concentrations at most compliance monitoring points that are outside of areas impacted by offsite VOC sources are less than the MCLs, meeting the Basin Plan 's definition of beneficial use . The remedial actions at the Landfill have restored the beneficial uses of groundwater in most zones affected by the release from the Landfill by the required date of July 1 , 2023, with the concentrations of PCE in the intermediate zone extending downgradient of the POC projected to reach MCLs within a period of 5 to 9 years . Additionally, residential treatment systems installed along Austin and Newcastle Roads continually provide water with no VOC detections to the residences. Because the POC groundwater system effectively captures VOC mass to prevent offsite migration and promotes a clean waterfront that will allow PCE concentrations in the intermediate zone to reach the MCL in a reasonable timeframe, and all potential domestic well receptors downgradient of the POC are receiving water free of VOC detections, no additional remedial action is proposed for offsite treatment of the intermediate zone . Since issuance of the CAO and the subsequent submittal of the revised FS report in 2019, additional investigation and testing activities conducted at 7833 Newcastle Road and the CDCR property have shown the presence of distinct VOC signatures compared to those associated with the Landfill 's POC. Additionally, access restrictions to the CDCR property from 2017 to 2020 had limited potential investigation of this offsite source and remedial action for these areas and delayed restoring the beneficial uses of groundwater in all zones by the CA Os required date of July 11 2023 . Therefore, Forward is recommending a revision to the CAO for the Landfill and downgradient properties to account for these separate source area (s) with independent VOC release (s) and the formation of a potentially commingled plume (s) on the CDCR property. Forward also recommends an additional phase (s) of investigation on the CDCR property to finish delineating the nature and extent of potential release (s) and VOC source masses beneath the property. When the localized source contributing to the carbon tetrachloride, PCE, and TCE concentrations greater than the MCLs in shallow groundwater at the CDCR property is delineated, Forward, Inc. will discuss the implementation of the proposed remedial alternative with parties associated with the VOC source mass beneath the CDCR property. " Response to Conclusion and Recommendations Aside from not completing installing the corrective action and treatment systems required by the CAO , the report is unacceptable because it is based on a pretense that restoration of the aquifer will occur when concentrations of VOCs in all affected groundwater zones are below the maximum contaminant levels contained in Title 22 of the California Code of Regulations . occurring and not detected in background groundwater samples shall be taken as the detection limit of the analytical method used (e. g. , USEPA methods 8260 and 8270) . "