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ARROYO LAGO RESIDENTIAL PROJECT ADDENDUM FCS 135 Https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480036/Addendum/21480036 Arroyo Lago Residential Project Addendum.docx Therefore, the Prior FEIR concluded that impacts would be less than significant. (Draft EIR, pp. 3.9- 24, 6-16). The Prior FEIR addressed comments from the City and other agencies regarding potential per- and polyfluoroalkyl substances (PFAS) concerns associated with wastewater treatment, effluent management, and water quality. As documented in the Prior FEIR’s Master Responses addressing wastewater treatment plant operation, effluent quality, and regulatory compliance, the County concluded that the County Project would comply with applicable State and federal PFAS regulations and would not result in significant impacts to groundwater or surface water quality (Final EIR, pp. 2- 34–2-35). Proposed Project Analysis and Conclusion Similar to the County Project, construction associated with the proposed project would include grading, excavation, and removal of vegetative cover that has the potential to result in runoff that contains sediment and other pollutants, such as fuel, grease, oil, and other fluids, that could degrade surface and groundwater quality, if not properly controlled. As construction of the proposed project would disturb more than 1 acre of land, compliance with the NPDES General Permit would be required, similar to the County Project. The General Permit would require the development and implementation of a SWPPP. The SWPPP would include site-specific BMPs, such as strategically placed silt fences and straw wattles to minimize erosion on-site and reduce or otherwise prevent conditions of erosion and stormwater runoff during construction. The proposed project would also be subject to the San Francisco Bay MRP, which includes LID standards and post-construction monitoring to encourage stormwater infiltration and retention. The proposed project does not include the water storage and booster pump facility, WWTP, recycled water storage, and agricultural irrigation fields included under the County Project, removing potential water quality impacts associated with these types of development that were identified and evaluated in the Prior FEIR, such as PFAS. Furthermore, the proposed project includes stormwater drainage facilities as described in the Project Description, which would ensure that stormwater is treated, detained, and conveyed to the appropriate facilities to prevent potential impacts related to stormwater drainage on the nearby lakes. As such, impacts related to surface and groundwater quality would be less than those disclosed in the Prior FEIR, although the less than significant impact conclusion would be the same for the proposed project and the County Project. Therefore, the proposed project would not introduce new significant impacts or create substantially more severe significant impacts than those previously identified in the Prior FEIR. No additional analysis is required.