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fl <br /> FYI <br /> 1) Review existing 2D CAD drawings and convert to 3D CAD to provide .stl files <br /> necessary for CFD analysis. <br /> 2) Review plant flow data and summarize for input to Flow-3D. <br /> 3) Build a CFD model of key plant hydraulic restrictions between the polishing pond, <br /> chlorine contact channel, and effluent pump station. <br /> 4) Run simulations to converge model to a stable solution. <br /> 5) Test grid resolutions to identify grid that can accurately describe flow features <br /> within a reasonable execution time. <br /> 6) Perform a sensitivity analysis of the grid resolution to main flow features. <br /> 7) Identify any dead and/or recirculation zones. <br /> 8) Determine the flow characteristics of the flow approaching the pumps (angle of <br /> swirl and/or deviation from average and temporal velocities). <br /> 9) Determine the mixing efficiency and estimated contact time of the current <br /> chlorination system. <br /> 10)HDR will test and recommend potential modifications to the effluent pump wet <br /> well and chlorine contact channel. Up to two potential modifications will be <br /> tested for each potential flow restriction (chlorine contact channel and the effluent <br /> pump wet well). Potential modifications will include a review (not model testing) <br /> of the recommendations provided in the previous report submitted by Carollo. <br /> 11)Develop a Visual Hydraulics model of flow through the weirs in the oxidation <br /> pond, polishing pond, chlorine contact channel, and the effluent pump wet well to <br /> integrate the CFD analysis with the overall plant hydraulics analysis. The <br /> hydraulic analysis will begin after mixing of the recirculation flow and inflow into <br /> the oxidation pond. The analysis will not include the mixing of these flows. <br /> 12)Summary Technical Memorandum of initial CFD and Visual Hydraulics model <br /> results and recommendations for 30% design. <br /> 4. Conduct two workshops with the Owner. First workshop will review the <br /> recommendations and findings. The second workshop will be to resolve issues and <br /> provide further clarifications as needed. <br /> 5. Develop a strategy for the modified plant hydraulics that includes flow control and <br /> conveyance modifications in the oxidation pond recirculation channel, from the oxidation <br /> pond to the polishing pond, from the polishing pond to the chlorine contact channel, and <br /> from the chlorine contract channel through the effluent pumps and outfalls. <br /> a) The design strategy will include preliminary Computational Fluid Dynamics (CFD) <br /> modeling as well as overall hydraulic grade calculations from the beginning of the <br /> oxidation pond through the outfall. <br /> b) A draft hydraulic profile will be provided as part of the Engineering Report. <br /> 6. Develop a Building Information Modeling (BIM) layout of the chlorine contact channel, <br /> effluent pumps, and new chlorine building. <br /> 7. Determine needed hydraulic modifications to the effluent pump station and discharge <br /> piping to achieve the desired 60MGD design flow. <br /> 8. Determine hydraulic modification to the oxidation and polishing ponds to achieve the <br /> desired 60MGD design flow and provide flow control. <br /> 9. Preliminary Engineer's Estimate of Probable Construction Cost: <br /> 2) Estimate o l.._ cc cost .oltov,i he expected e! of 2.0ou,h2c!for afi <br /> r: <br />