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Ken Mercer Sports Park Skatepark Construction Documents Scope of Services rrm April 20, 2022 • esign Page 2 of 9 group Horizontal Control Plans The plans will establish all horizontal control for the Skatepark and surrounding amenities. The plans will also identify construction layout control points and a coordinate system for locating site elements. Note that the horizontal control plans are not included in the 60% PS&E submittal. Site Utility Plans Utility plans for water and storm drain begin at the upstream ends of each utility within the project limits to the downstream connections at the existing service mains, assumed to be directly adjacent to the project. Water utilities are for a drinking fountain and the storm drain is for connecting proposed storm drain and stormwater treatment measures to the existing downstream storm drain system. This scope assumes that existing off-site and/or on-site utility systems have adequate capacity and meters for the proposed project—analysis of existing utilities' capacities and design of any improvements beyond the point of connection are not included in this scope. This task assumes one proposed fire hydrant located near the existing or proposed parking lot will suffice for Fire Code/Fire Department compliance—fire supply line is assumed to be fed by existing on site meter. Grading. Drainage and Stormwater Plans The plans will show all vertical control of the project elements, contour grading, spot elevations, and cut and fill estimates within the project site. The plans will detail all drainage facilities within the site. This scope is limited to the project site only (approximately three acres) and assumes that the existing off-site upstream and downstream storm drain infrastructure has adequate capacity for the proposed site development, and analysis or upgrades to this infrastructure is not included. Stormwater evaluation to include the following: • This project is assumed to create and/or replace more than 10,000 square feet of impervious surface and is a C.3 Regulated Project. RRM will design permanent stormwater treatment in accordance with the C.3 Stormwater Technical Guidance (C.3 Guide, February 2021). Per Appendix I of the C.3 Guide, this project is in a hydromodification susceptible area—this task assumes the project will require hydromodification measures using Bay Area Hydrology Model 2013 (BAHM) for sizing. The design will utilize a combination of low impact development (e.g., interceptor tree credits, self-retaining areas, self-treating areas) and stormwater treatment measures (e.g., bioretention, pervious pavements). RRM will prepare a City of Pleasanton Stormwater Requirements Checklist and C.3 sizing calculations • RRM will perform ten year storm drainage analyses (hydrology and hydraulic) for the project drainage, pump, and Stormwater designs. The pump will be designed to pump stormwater collected by the skate park's drainage system to the proposed stormwater treatment measures. The C.3 calculations and exhibits, storm drain hydrologic/hydraulic calculations and exhibits, reference documentation, and project narrative will be provided in a comprehensive drainage and stormwater control plan