Agmt 2013 RMC Water and Environment

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evaluations is to confirm the suitability of pipeline alignments, and identify any design, constructability, permitting, or environmental issues that could potentially be"fatal flaws"or that should be considered in project development. RMC will develop planning level cost estimates based on the most viable construction method for each potential solution for the identified deficiencies. Subtask 5.4 Evaluate Alternatives for Valley Area RMC will review the alternatives for conveying Valley Area flows to the San Leandro WPCP that were developed in the 1998 Valley Area Wastewater Export Study. RMC will use the hydraulic model to confirm or update the required facilities for conveying flow to the San Leandro WPCP under each of those alternatives, and will update the estimated costs of the alternatives. The alternatives will be compared to the estimated future costs of continued conveyance and treatment at Oro Loma Sanitary District(OLSD). Potential future capital projects that might be needed by Oro Loma Sanitary District(OLSD)to convey Valley Area flows will be discussed with the District. The alternatives will be compared on the basis of capital and operating costs(including cost of pumping and treatment), constructability, system reliability, community and environmental impact, permitting requirements, and other factors to be discussed with the City. Task 5 Deliverables: • Thematic maps and hydraulic grade line plots of predicted capacity deficiencies • Concepts and estimated costs of proposed Capacity Improvements • Concepts and estimated costs of Valley Area Alternatives. Task 5 Assumptions: • City will provide cost of treatment at San Leandro WPCP and facilitate obtaining similar information from OLSD. • No new alternatives for the Valley Area will be developed. Task 5 Schedule: • All items delivered by September 30, 2013 Task 6–Lift Station Reliability Evaluation This task will evaluate the length of time that each of the City's 13 lift stations may be out of service without resulting in an overflow under dry and wet weather conditions, and identify potential opportunities for increasing lift station reliability Subtask 6.1 Determine Lift Station Time to Overflow Using the information developed in previous tasks, RMC will estimate the dry and wet weather flows for each lift station. For lift stations included in the modeled system,the hydraulic model will be used to simulate the shut-down of each station under typical dry weather diurnal flows and under both a design storm wet weather flow condition and a more moderate storm event. The resulting hydraulic grade line results from the model, elevation data for surrounding manholes in the system, and pump station design drawings will be used to identify the likely overflow points under a system shut-down and the time to overflow. For lift stations not included in the model,flow estimates will be calculated based on the tributary area of each lift station and the flow factors developed under Subtask 4.2, and the available storage upstream of the station will be estimated based on the wet well volume and upstream piping. Consulting Services Agreement between City of San Leandro and RMC Water and Environment—Exhibit A Page 6 of 9