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EXHIBIT A <br />SCOPE OF WORK <br />1 <br /> <br />City of Everett <br />Water Pollution Control Facility Headworks Replacement Project <br />Project Understanding <br />The City of Everett (City) operates the Everett Water Pollution Control Facility (WPCF) for the <br />protection of regional water quality through the safe treatment and disposal of wastewater from over <br />180,000 residents. The WPCF is located on a 350-acre site on Smith Island, bordered by Interstate <br />5, the Snohomish River, and Union Slough. The facility has a designed treatment flow of 40.3 million <br />gallons per day, providing secondary treatment through parallel mechanical and biological <br />processes. The s service area spans approximately 15 square miles and includes a combined <br />system in the North End and separated systems in the South End. It is also a service provider to <br />neighboring municipalities, including Alderwood, Mukilteo, and Silver Lake water and sewer districts. <br />The WPCF headworks, constructed in the early 1980s, is the entry point to one of the City <br />critical pieces of wastewater infrastructure. This multi-story structure provides uninterrupted <br />operation with frequent 24-hour wet weather influent flows up to 100 million gallons per day (mgd) <br />and peak instantaneous flows that have exceeded 250 mgd. Decades of continued service in a <br />highly corrosive environment have led to facility degradation, key mechanical systems are beyond <br />their service life, and the structure is seismically vulnerable. The following scope of work outlines the <br />initial design phase for replacing the WPCF headworks. <br />Scope of Work Summary and Work Breakdown Structure <br />This scope of work reflects alternatives analysis through intermediate design services for <br />construction of a new WPCF headworks facility. This scope of work assumes GC/CM delivery and was <br />developed prior to the preliminary design, and as such, the configuration and requirements of the <br />headworks facility were not yet defined. As a result, design assumptions were made regarding facility <br />layout, process needs, and mechanical systems for level of effort budgeting, which included <br />development of a preliminary drawing and specification lists (see Attachment A). This drawing list, <br />which includes 362 sheets, and the following scope of work outline the key components anticipated <br />for the headworks facility upgrade. These elements are intended to guide project scoping and budget <br />development and will be further evaluated during the alternatives analysis phase. These features <br />include the following: <br /> Construction of a new pile-supported headworks structure designed to house all major <br />preliminary treatment processes, including influent pumping, screening, and grit removal. <br /> The structure will be fully enclosed and will include an integrated electrical room required for <br />the associated headworks process mechanical equipment. <br /> Installation of four parallel Archimedes screw pumps located at grade elevation, upstream of <br />the screening equipment. <br /> Placement of five parallel mechanical bar screens with ¼-inch spacing, located on the <br />second story of the headworks building. <br /> Each screen channel will be equipped with upstream and downstream stainless steel slide <br />gates to facilitate channel isolation. <br /> A bypass channel to accommodate screen isolation for maintenance and emergency flow <br />conditions. <br /> A conveyor system will be installed to transport screenings from the bar screens to an <br />offloading bay integral to the headworks structure.