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EXHIBIT B City of Pleasanton Recycled Water Infrastructure Expansion Phase 1A Design of Additional Improvements Proposed Booster Pump Station and Reservoir Improvements Scope of Work Task 12—Tassajara Reservoir Altitude Valve Purpose: The City proposes to install an altitude valve at the Tassajara Reservoir to protect against overfilling and potential discharge of recycled water through the existing overflow piping. Under normal operation of the reservoir,the altitude valve would remain open. Upon water level reaching pre-set high level in the reservoir,the pressure detected at the valve via a small diameter sensor line would initiate an automatic closure of the valve. Once the altitude valve is closed, pressure in the recycled water system would increase, and one or both of the supply flow control valves would close. Current control strategy for supply flow control valves is to close the valves at an adjustable reservoir elevation or high pressure on the system. The set point of the supply valve closure should be below the altitude valve closure set point to keep the system normally floating on the Tassajara Reservoir elevation. Task Description: RMC shall perform the following: • Size and select an altitude valve for the projected maximum reservoir fill rate assuming both Livermore and DERWA supply turnouts are open, • Assess advantages and disadvantages of City's two alternative altitude valve layouts(with and without fill bypass) based on recycled water system configuration and proposed operations, • Prepare a brief technical memorandum of the evaluation results,and discuss the results with the City to determine preferred alternative, • Prepare sketches for piping and valving modifications that will be required to implement the preferred altitude valve alternative, including pipe and valve supports,within existing Tassajara Reservoir valve vault for purposes of generating a construction change order request under the Recycled Water Infrastructure Expansion Phase 1A contract. • Review the contractor's change order proposal and provide input to the City, Assumptions: • The construction will be performed under a change order to an existing contract • Change order request will consist of sketches and material lists only. Formal design drawings and technical specifications will not be prepared. Task 13—Recycled Water Booster Pump Station Purpose: The City is anticipating difficulty in achieving adequate recycled water distribution system pressures at the Sports Park during periods of high demand. Inadequate pressure (less than approximately 60 psi at the sprinkler rotor) reduces coverage by each rotor, resulting in unsatisfactory appearance and browning of the turf grass. In addition,the City is exploring extending the recycled water distribution system south along Valley Avenue to significant irrigation demands at and south of Bernal Avenue,extending ultimately to the Callippe Reserve Golf Course. Scope of Work 1 June 30,2016