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The six scenarios could include: • Serving the north of Pleasanton from the LWRP and using Tassajara Reservoir for storage — mainly from Staples Ranch to Hacienda Business Park • Serving the west side of Pleasanton from a new satellite plant • Serving the west side of Pleasanton from DSRSD • Serving the west side of Pleasanton from DERWA • Interconnecting the DSRSD and LWRP pipelines and serving the north and west • Some miscellaneous combination sources and demands The scenarios will also consider implementation timing and phasing. Advantages and disadvantages will be identified for the scenarios. The identified location of the new satellite facility is the City site across from the DSRSD WWTP. The possible storage facilities are two existing water reservoirs: Tassajara Reservoir located north of Hwy 580 and Fairland's Park and a reservoir located between Vintage Hills Park and Ruby Hill Golf Course. The quarries will also be considered for tertiary recycled water storage. For other storage needs, a reservoir size will be determined and generally located based on elevation need. Direct injection or surface spreading for groundwater recharge or formally siting a new reservoir will not be considered as part of this study. Desalting of the water supply will also be briefly discussed in regards to which is more beneficial — removing the salts from the drinking water supply side or the recycled water irrigation/process side. This will be a big-picture, general discussion geared towards the inherent benefits of both salt reduction methods. 2.2 Scenario Modeling, Comparison, and Recommendation Carollo will create a simplified, user-friendly hydraulic model of the scenarios using H2OMap software. This task will include extracting the necessary spatial information from existing databases and the user database developed in Task 1. The model will also be used to ensure basic system operability such as pressures, pump sizing, storage requirements, and operation. The scenarios will be compared, screened, and ranked into order of program preference. The top ranked scenario will be described and developed further for planning recommendation. At a minimum, the description will contain the final customers, demands, treatment facilities, pipeline routing and sizing, pumping and storage, system operating pressures, and costs. Split of Services under Task 2: Carollo team: - Determine draft project scenarios and review with the City in workshop - Identify quantitative and qualitative project scenario data - Develop model and conduct preliminary hydraulic modeling of up to six scenarios (some scenarios will have some model based on same source) - Preliminarily screen scenarios to one preferred scenario - Develop and further define preferred project Zone 7: - Determine regional storage locations and summarize advantages and disadvantages (i.e. quarries — Chain of Lakes) - Revise project scenarios with regional storage, identify quantitative and qualitative scenario data, and determine if more advantageous than local storage options - Help to fill in quantitative and qualitative project scenario data