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EXHIBIT A ci en pea Ian Engineers...Working Wonders With Water October 17, 2012 Mr. Stephen Kirkpatrick P.E. The City of Pleasanton 200 Old Bernal Ave. Pleasanton, CA 94566 Subject: Peer Review of East Amador Relief Sewer Capacity and Collection System Hydraulic Model Conversion Dear Mr. Kirkpatrick: This letter is per your request for a proposal to perform a peer review of designing the East Amador Relief Sewer Pump Station (EARS PS) assuming a firm capacity of 2 mgd. This proposal also includes a conversion of the Cit9s wastewater collection system hydraulic model to H2OmapSWMM. BACKGROUND The City has performed a preliminary engineering analysis and has determined installing the EARS PS with a firm capacity of 2 mgd will adequately convey average daily flows from the contributing sewer sheds. The City is planning to operate the East Amador Lift Station (EALS) minimally during dry weather and the EARS and EALS pump stations in parallel during wet weather flow events. Carollo has developed the following scope of work based on this operating scenario. The City's wastewater collection system hydraulic model was constructed in the H2OMapSewer software as part of the 2007 Wastewater Collection System Master Plan. It is necessary to convert the hydraulic model to H2OmapSWMM to perform the hydraulic analyses required to evaluate the hydraulics of the EARS and East Amador Trunk Sewer(EATS) sewer collection pipelines assuming the EARS PS is constructed with a 2 mgd firm capacity. The hydraulic model conversion will provide the City with a robust hydraulic modeling platform that will allow analysis of surcharged and backwater hydraulics, as well as the evaluation of impacts to the collection system of installing flow diversions between existing trunk sewers. In general, this scope of work converts the hydraulic model to H2OmapSWIMM and evaluates the hydraulics in the EARS/EATS sewer systems during peak wet weather flow, reviews impacts of the new operating scenario, and provides operating recommendations. This scope of work includes the following tasks: SCOPE OF WORK Task 1 —Conversion of Hydraulic Model The purpose of this task is to convert the Citys current hydraulic to H2OMapSWMM and to update the model to reflect current and projected flow conditions in the East Amador Trunk Sewer(EATS)for both dry and wet weather conditions. 2700 Ygnacio Valley Road,Suite 300,Walnut Creek,California 94598 P.925.932.1710 F.925.930.0208 pwJ/CardldDocumenWClienl/CNPleasanlont Praposals/EARS Pump Staton/DoWFARS Scope Letter(B) carollo.com