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EXHIBIT A <br />Task 202 - Assess Hydraulics <br />Assess hydraulics of the CS bypass from the plant headworks and primary clarifier <br />overflow points to the Oxidation Pond recirculation channel: <br />1. Confirm findings of the CS Conveyance Study which recommended two 78-inch <br />bypass pipes. <br />2. identify the size and/or shape of conveyance conduits required for the Aerated <br />CeII 2 option to work hydraulically. <br />3. Prepare a hydraulic profile showing hydraulic grade line from the plant <br />headworks and primary clarifier overflow points to the recirculation channel for <br />maximum, 50% of maximum, and 10% of maximum CS bypass flows. <br />4. Review hydraulic feasibility of the Aerated Cell 2 option with City staff. <br />Task 203 — Conveyance Concepts <br />Refine the CS Conveyance Study option concepts and prepare conceptual layouts for <br />the Aerated CeII 2 option: <br />1 Use computational fluid dynamic modeling to prepare concepts for the new <br />diversion structure and recirculation channel discharge structure for the CS <br />Conveyance Study option. <br />a. Prepare figures showing concepts for the diversion structure and <br />recirculation channel discharge structure. <br />2. Using information from Tasks 201 and 202 and computational fluid dynamic <br />modeling results prepare conveyance system concepts for the Aerated CeII 2 <br />option <br />a. Prepare figures showing both a conceptual layout of the conveyance <br />system and profiles for the Aerated CeII 2 option structures and <br />conveyance conduits. <br />b. Summarize operation of the conveyance system for flow conditions: <br />i. When there is no CS bypass flow. <br />ii. When there is CS bypass flow. <br />3. Review proposed conveyance system concepts, including operation with and <br />without CS bypass flows, with City staff and refine based on City staff <br />comments. <br />Task 204 - Environmental Assessment <br />Provide an opinion regarding environmental permitting and documentation requirements <br />for the two conveyance options highlighting similarities and differences. For the CS <br />Conveyance Study option consider the work will be open cut construction through the <br />wetland and that a future project will be needed to replace the conveyance conduits from <br />Aerated CeII 2 For the Aerated Cell 2 option consider the multiple benefits of replacing <br />aged conveyance pipes and the ability to isolate the construction area from the <br />wetlands: <br />1. Review alternative concepts prepared under Task 203. <br />2 Conduct a site tour to become familiar with the project sites and understand the <br />wetland areas impacted. <br />pw:WA\Everettl__Proposals\Combined Sewage Conveyance Improvements\Admin\WPCF CS Bypass Project.doc <br />Page 3 of 5 <br />