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Aubrey Rose November 8, 2024 Page 5 •The project has stormwater being directed to a bioretention basin within the lower elevation portion adjacent to Cope Lake. Stormwater from the development is at risk of containing PFAS, pesticides, nitrates, TPH, among other contaminants. Engineered bioretention basins are not currently designed to remove PFAS. In addition, bioretention basins require continued maintenance and are not a one-time solution. The plan does not address the ongoing maintenance needs for standard treatment and does not address PFAS It is essential to ensure that the project will not degrade water quality in both surface water and groundwater through runoff or infiltration. Significant project concerns requiring improved evaluation and possibly mitigation measures in the DEIR include: •Risk of upset / impacts of an upset at the sewer plant •Introduction of PFAS, heavy metals, nitrates, and other contaminants to Cope Lake, Lake I, and the groundwater basin •Solids handling •Stormwater entering Cope Lake •Downstream surface water quality concerns such as PFAS or others •Spray fields leaching into the groundwater basin •Vector control issues with respect to the spray fields •Public health and safety in and around the development It is imperative that the basin groundwater quality is protected and managed to prevent any further degradation. The DEIR must adequately evaluate the project’s potential water quality impacts to Cope Lake and to Lake I, as well as to nearby surface waters. This includes impacts from operations of the proposed sewer treatment plant – including contribution of PFAS to the groundwater basin via wastewater effluent; the bioretention areas; and overspray or leaching of contaminated water from the irrigation spray fields. The DEIR does not adequately address public health, safety, and ongoing operational concerns at Lake I. Beyond these water quality concerns, Zone 7 has specific reservations regarding the DEIR’s analysis of physical conditions and the Project’s impact at Lake I and Cope Lake. Both Lake I and Cope Lake are closed to the public and there are no current plans to make these lakes accessible for recreation or other access. Notwithstanding that fact, Zone 7 routinely patrols the area and it is not unusual to find individuals (trespassers) fishing at Lake I in particular. The slopes are steep and, in some cases, have uneven terrain not suitable for access without proper safety equipment. In addition, the water in the lakes can be deep and poses a hazard to trespassers if they accidentally fall in. With increased development in the region, the opportunity for further trespassing may increase.