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EXHIBIT A-3 7 <br /> SCOPE OF WORK <br /> Task 6. Predesign Analysis <br /> Develop the preliminary design concept for the replacement of Pipelines No. 2 and 3 based on <br /> using HDD construction method for most of the Phase 6 length. The work will include the <br /> following: <br /> A. Develop Predesign. Analyze and develop recommended construction approach, material <br /> selections, and design parameters for the Phase 6 HDD project. The analysis will determine <br /> location of pipelines, proximity to existing structures, and construction scheduling <br /> requirements. Provide recommendations for the HDD entry and exit locations, pipe <br /> alignment and bore geometry and determine the staging area requirements for HDD <br /> installation. Perform pipeline HDD design calculations to adequately size pipe and <br /> determine pull-back and combined stress loading of pipe. Review the existing Phase 6 <br /> (2005) pile bent support system design and propose modifications relevant to the proposed <br /> Phase 6 HDD project concept. Evaluate using a buried pipe configuration located at the <br /> east end of Phase 6 to transition from HDD to the existing buried pipe located adjacent to <br /> Home Acres Road. Evaluate existing piping connections, construction access and general <br /> staging needs, and potential mitigation requirements. Refine the conceptual construction <br /> cost opinion developed and presented previously in MWH's March 2006 Memorandum <br /> which discusses re-evaluation of Phase 6 design alternatives. <br /> B. Review Operation Requirements and Construction Sequencing. Evaluate the proposed <br /> preliminary design concept for operational requirements and construction sequencing to <br /> minimize impacts to the City of Everett's water supply system operations and existing level <br /> of service. <br /> C. Evaluate Corrosion Protection System Requirements. Develop preliminary design <br /> recommendations for coatings and corrosion protection for the pipes, as follows: <br /> 1. Review interior and exterior coating system options for the HDD and buried pipeline <br /> sections. <br /> 2. Evaluate two alternative design concepts (impressed current and galvanic anode) for <br /> implementing a cathodic protection system on the buried and elevated pipeline <br /> sections of the Phase 6 project. In addition, consider a design method to provide <br /> corrosion protection of the HDD pipe located within the proposed casing positioned <br /> at each end of the HDD section. <br /> 3. Prepare a brief memorandum addressing updated information on the existing <br /> corrosion control facilities and conditions, preliminary coating system <br /> recommendations for the buried and HDD steel pipeline, initial cathodic protection <br /> design parameters and considerations for the HDD, and buried pipeline sections. <br /> Provide budget level cost opinion for the recommended pipe coating and cathodic <br /> protection system. Eight (8) copies of a draft memorandum and eight (8) copies of <br /> the final memorandum will be provided to the City <br /> 46 <br /> MWH Page 6 EVERETT PHASE 6 HDD PROJECT <br /> 51/06 EXHIBIT A-3-SCOPE OF WORK <br />