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Ponderosa Homes at 6900 Valley Trails Drive Initial Study and Negative Declaration DISCUSSION a,e,f) Compliance with the Alameda Countywide Clean Water Program (ACCWP) National Pollutant Discharge Elimination System (NPDES) Permit, including C.3 provisions and implementation of a Construction Stormwater Prevention Pollution Plan, would regulate discharges to the municipal stormwater system and reduce potential water quality impacts. The project would be required to incorporate best management practices (BMPs) for discharges resulting from the project through the building permit and construction process. As a standard condition of approval, the project would prepare and implement a Stormwater Pollution Prevention Plan (SWPPP) during construction. These measures would include but not be limited to: erosion controls to prevent soil, dirt, and debris from entering the storm drain system and canals; grading controls (e.g., timing, hydroseeding); traffic controls to prevent erosion from construction equipment; filters (e.g., waddles) on inlets; covered storage areas; and measures to control pollutants at wash out areas. These and similar measures in the SWPPP would filter contaminants from the stormwater before entering local arroyos and, ultimately, San Francisco Bay. During operation of the project, the project is required, by standard conditions, to collect and convey all stormwater entering and/or originating from the development to an adequate downstream drainage facility. The geotechnical report also recommends that surface runoff should be designed to drain away from building foundations and flatwork, speed up infiltration, and reduce the potential for expansive soils; these measures are required as conditions of project approval.12 The project proposes bioretention areas in curb bump-outs along the street edge and open space areas at the end of each cul-de-sac to manage runoff from the site. The project sponsor is required to enter into a recorded Stormwater Operation and Maintenance (O&M) Agreement for treating stormwater runoff from the site in perpetuity. This agreement calls for maintaining landscaping with minimal pesticide and fertilizer use; preventing disposal of vehicle fluids and hazardous materials from cleaning tools and equipment; cleaning out on-site storm drains twice per year; and maintaining vegetative swales on a regular basis.Therefore, these potential impacts would be less than significant. b) The project would not use groundwater to provide water for this project. The bioretention and other landscaped portions of the project site (i.e., private yards) would allow for the groundwater aquifer to be recharged after 12 Cornerstone Earth Group, 2014. 29