14 ATTACHMENT 6 - Appendix A - E

City of Pleasanton–Spotorno Ranch Reduced Development Project Environmental Checklist Initial Study/Consistency Checklist 118 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 control measures during operational activities to prevent pollutants from entering downstream waterways. Therefore, the proposed project would not result in any peculiar effects and would not result in new or more severe impacts related to water quality beyond what was previously analyzed in the 1998 HVSP FEIR. b) Groundwater Would the project: Substantially decrease groundwater supplies or interfere substantially with groundwater recharge such that the project may impede sustainable groundwater management of the basin? The 1998 HVSP FEIR determined that extension of the City's sewer system to the Happy Valley Area, and connection of existing as well as new homes to that system, would help to improve the quality of groundwater in the area. Additionally, the 1998 HVSP FEIR determined that because the proposed water supply would not rely on groundwater withdrawals but instead on the City’s water supply, the proposed project would not have an adverse impact on groundwater supplies. The 1998 HVSP FEIR concluded that groundwater impacts would be less than significant. The City purchases approximately 80 percent of its water from Zone 7 Water Agency and obtains the remaining approximately 20 percent from groundwater. The City owns and operates three active groundwater wells in the Main Basin, which is a portion of the Livermore Valley Groundwater Basin. Through a mutual agreement with the Zone 7 Water Agency, the City of Pleasanton has a groundwater-pumping quota (GPQ) of 3,500 acre-feet per year (AFY). The Main Basin is the portion of the Livermore Valley Groundwater Basin that has high yields and good quality groundwater. The Main Basin has an estimated storage capacity of 254,000 acre-feet and receives an annual average natural recharge of approximately 13,400 AFY. This recharge is considered the long-term natural sustainable yield of the Main Basin. Historical groundwater pumpage from 2011 to 2015 has been about 3,500 acre-feet, equal to the City’s GPQ. The proposed project would demand approximately 10.42 AFY; refer to Section 4.19, Utilities and Service Systems for further discussion. Water for the residential development area of the project site would originate primarily from surface water; therefore, the proposed project would not deplete groundwater supplies. No new on-site groundwater wells would be drilled as part of the proposed project. The proposed project would connect to the City’s existing water infrastructure. Furthermore, a majority of the project site would remain undeveloped. There would be two drainage management areas (DMAs) on the project site. Storm drainage from impervious surfaces would be directed to on-site bioretention areas and self-retaining areas where infiltration could occur. As such, the proposed project would not substantially interfere with groundwater recharge. Therefore, the proposed project would not result in any peculiar effects and would not result in new or more severe impacts related to groundwater beyond what was previously analyzed in the 1998 HVSP FEIR.