14 ATTACHMENT 6 - Appendix A - E

City of Pleasanton–Spotorno Ranch Reduced Development Project Environmental Checklist Initial Study/Consistency Checklist 164 FirstCarbon Solutions https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480021/Consistency Checklist/21480021 Spotorno Ranch Consistency Checklist ScreenCheck.docx underground throughout the site and eventually empty into a bioretention area on the western portion of the project site facing Alisal Street. The proposed project site would contain two DMAs, bioretention areas, and self-retaining areas. The total bioretention area proposed by the project would amount to approximately 26,650 square feet. DMA 1 includes Lots 13 through 15 and features 1,800 square feet of on-site bioretention that would discharge to Westbridge Lane through curb drain systems. DMA 2 spans from Lots 1 through 12 and 17 through 22 and would feature a 36-inch storm drainage pipeline leading to the bioretention area on the western portion of the site, which would connect to an existing 36-inch storm drainage pipe located within Alisal Street. DMA 3, located entirely on Parcel C located east of project development and where the building restricted area starts, comprises self-treating systems that would feature conserved natural spaces. Sizing factors and design guidelines would be based on the combination flow/volume sizing criteria set forth in the 2017 Alameda County C.3 Stormwater Technical Guidance Handbook.53 Additionally, the proposed project’s landscaping plans feature groundcover and bioretention areas to increase infiltration rates and reduce runoff volumes and erosion and sedimentation. Furthermore, the project would be required to implement stormwater BMPs that limit the volume and flow of stormwater to the municipal storm sewer system. Therefore , the proposed project would not result in any peculiar effects related to stormwater and would not result in new or more severe impacts beyond what was previously analyzed in the 1998 HVSP FEIR. b) Water Supply Would the project: Have sufficient water supplies available to serve the project and reasonably foreseeable future development during normal, dry and multiple dry years? The 1998 HVSP FEIR determined that the residential component of the project would total 506,327 gallons of water per peak day and concluded that impacts associated with water supply would be considered less than significant with implementation of MM E1 and MM E3. The 1998 HVSP FEIR determined that a cumulative impact related to water supply may occur. The water demand of the HVSP, together with demand generated by other future development, would contribute to Zone 7's anticipated need to expand its available water resources in order to meet buildout water needs of its service area. A significant impact would occur if the proposed project would require or result in the construction of new water facilities or expansion of existing facilities that could cause significant environmental effects. As previously discussed, the estimated 110 new residents would use an estimated 17.32 AFY, which represents approximately 0.09 percent of the 2025 water supply for the City of Pleasanton. Thus, the City has adequate water supply to provide for the proposed project. The projected water usage of 17.32 AFY for the proposed project would be within the threshold discussed in the 1998 53 Clean Water Program 2017. C.3 Stormwater Technical Guidance. Website: https://www.cleanwaterprogram.org/images/uploads/C3_Technical_Guidance_v6_Oct_2017_FINAL_Errata_updated_04.20.18.pdf. Accessed February 17, 2021.