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6.B. - Page 26 of 39 !( � KennedyJenks match or be compatible with the background levels of water entering the Pulgas Facilities to aid in the treatment at the Pulgas Dechloramination Facility. A specific point of connection or options for the point of connection for purified water to enter the Pulgas Facilities will be identified by SFPUC. Assumptions: SFPUC to provide input on Pulgas Facilities to describe current operations and potential adjustments to accommodate augmentation of 6 to 12 mgd of purified water year-round, including but not limited to the preferred point of connection, treatment considerations, and potential use of the balancing reservoir. SFPUC to provide monthly water quality data over a 6 -year period for influent to the Pulgas Facilities, ideally aligning with the flow scenarios identified in Task 1.2. Deliverables: Write up summarizing current Pulgas operations and water quality characteristics of influent flows, which will be incorporated into the Phase 3 Study in (Task 3). 1.5 Reservoir Operations Model (ROM) The intent of the ROM is to (1) simulate how the project would meet regulatory requirements (detention/dilution) and (2) provide input to RWS model (Task 1.6) regarding the amount of Hetch Hetchy what that would essentially be held back to make room for purified water in CSR. The ROM will be developed using Microsoft excel and will use a monthly timestep to simulate historical reservoir conditions over the flow scenarios defined in Task 1.2. The ROM input will include daily reservoir inflow, outflow and CSR volume data provided by SFPUC as part of Phase 2, and supplemented by new data as - needed. SFPUC to provide operating constraints to establish model boundary conditions (e.g. min/max reservoir levels and flows on a monthly basis). A monthly analysis of retention and dilution analysis for the 6 mgd and 12 mgd RWA alternatives will be performed. A qualitative discussion of mixing mechanisms within the reservoir (e.g. diffusers, aerators, solar bees, etc) and potential for water quality impacts (such as algal blooms) will be discussed at a high-level. Assumptions: SFPUC to provide input on current CSR operational assumptions, boundary conditions and ROM output. Matt Moses to participate in initial call to define reservoir model assumptions and a check- in call to review initial outcomes, which will aim to support SFPUCs determination of extent of operational adjustments that may be necessary for CSR to receive recycled water year-round. This task does not include development of a hydrodynamic or biological model of the reservoir, which is not warranted at this time but would be developed in parallel with conducting tracer studies and water quality monitoring at a future stage in the project. Deliverable: Technical Memorandum (TM) #1 describing the ROM, assumptions and outcomes with summary tables, maps and graphs. A Draft and Final TM #1 will be submitted, and included as an appendix to the Phase 3 Study (Task 3). 1.6 Regional Water System (RWS) Considerations Regional Water System (RWS) Considerations: The RWS evaluation will assess at a high level if there is capacity for the purified water in the reservoir on a monthly basis, and if there is insufficient room, then that volume of water would need to displace water from the RWS that would otherwise be delivered to CSR to make room for the local purified water. The monthly volume of displaced water will be estimated Page 4 48 ATTY/AGR.2020.216/MOA- SVCW, SFPUC, BAWSCA, Cal -Water, City of San Mateo (Page 23 of 36)