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EXHIBIT A <br /> SCOPE OF WORK <br /> Bond Street Retention Treatment Basin (RTB) Process <br /> Validation and Cost Estimate Review <br /> Background <br /> The City of Everett Bond Street RTB was designed to capture and treat excess combined <br /> sewage that is currently being discharged as combined sewer overflows (CSOs) at Puget <br /> Sound Outfalls PSO4, PSO5, PSO6 and PSO7. The design concept was to provide primary <br /> treatment meeting the State of Washington's criteria of 50% removal of solids on an average <br /> annual basis. The treatment approach and design were approved by the Washington State <br /> Department of Ecology following the submission of final design in 2008. <br /> Following the completion of the Bond Street RTB design, the City of Everett developed a <br /> concept of an alternative wet weather facility that would treat combined sewage and storm water <br /> at the Kimberly Clark facility. The Bond Street RTB construction was postponed indefinitely <br /> pending the development of the alternate facility. <br /> Task 1 — Bond Street RTB Review <br /> Objectives <br /> The City of Everett would now like to review the original Bond Street RTB concept to verify that <br /> the facility would still meet the treatment requirements for CSOs and reassess the construction <br /> cost. The key goals of this effort is to <br /> 1. Document the compliance with CSO control requirements <br /> 2. Evaluate the potential to eliminate or reduce discharges to near shore shallow outfalls <br /> 3. Reduce basement flooding <br /> 4. Provide resilience in the facilities <br /> HDR Services <br /> 1. Using CSO data from at least the last 5 years evaluate the predicted performance of the <br /> Bond Street RTB with regard to meeting primary treatment standards. <br /> 2. Use the Bond Street spreadsheet based model to predict the flow response from the <br /> rainfall over the last five years and validate the model calibration. <br /> 3. Predict the flow response from a climate change adjusted rainfall time series for at least <br /> a 20 year period and evaluate if the Bond Street RTB will continue to meet treatment <br /> standards for CSOs. <br /> 4. Review and update the construction cost estimate based on current construction cost <br /> data. <br /> 5. Document the predicted performance of the Bond Street RTB based on current and <br /> climate change impacted rainfall predictions in a summary technical memorandum. <br /> City of Everett— Bond Street RTB Review Scope of Work <br />