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rise. Virtual tracers shall be included with each simulation to visualize the changes in circulation as weil <br /> as to quantify the local and overall change in volume exchange rates. <br /> Subtask 3-3 Simulation Analysis and Interpretation <br /> Following the execution of the simulations,the Consultant shall document the modeling results as figures, <br /> animations, and summary tables. Consultant shall then meet with the City to present and discuss the <br /> simulation results. <br /> The Consultant shall deliver the following: <br /> • An engineering memorandum presenting the results of the simulations that will include a <br /> comparison of the volumetric exchange rate for the several proposed lagoon modifications <br /> and shall provide maps showing spatial variations in the rate of tidal exchange across the <br /> lagoon. This memorandum shall be submitted for review following the completion of Task <br /> 3-2 and form the basis for the meeting with the City. A revised version of the memorandum <br /> shall be submitted as an appendix of the Preliminary Engineering Report to be produced <br /> under Task 4. <br /> • A presentation to given by the Consultant staff describing the model development, <br /> selection of lagoon modifications, and simulation results. We anticipate that the <br /> presentation will be attended primarily by City staff and representatives; however additional <br /> parties would be welcome at the invitation of the city. <br /> Task 4 Prepare Preliminary Engineering Report <br /> The Consultant shall prepare a preliminary engineering report which will compile and discuss the results <br /> of Tasks 1 through 3. This report shall include a conceptual-level description of each of the proposed <br /> lagoon modifications. <br /> For modifications which involve earthwork, dredging, new construction and/or modifications to existing <br /> structures, the report shall include figures depicting the location and spatial extent of the proposed <br /> modifications and typical cross sections, as appropriate. For modifications which involve changes to <br /> lagoon operations and maintenance practices, the report shall describe typical procedures to be <br /> implemented under the proposed modifications including a description of proposed methods, equipment <br /> requirements and scheduling considerations. <br /> The report shall summarize the results of the 2D hydraulic model simulations for each set of lagoon <br /> modifications. The report shall focus on comparing the modeled volumetric exchange rates for each set <br /> of modifications, both with respect to lagoon-wide flushing as well as identifying localized areas with poor <br /> mixing and exchange. Other relevant output, such as water levels, current velocities, and bed shear <br /> stresses, shall also be discussed and the report shall also comment on the general feasibility and <br /> effectiveness of each set of mod�cations. <br /> Based on consultation with the City and the results of the circulation analysis,the Consultant may provide <br /> recommendations on possible source control and BMP measures. These source control measures will be <br /> consistent with the City's Stormwater Management Plan and provide an overall cost effective program to <br /> mee#the water quality goals. It is our experience that while improved circulation can significantly improve <br /> water quality, source control and BMP measures may be cost effective augmentations to reduce the <br /> nutrient loading that leads to water quality issues in developed settings. <br /> REV:0409-14 VR <br /> Page 13 of 16 <br /> ATTY/AGR.2014.048/ESA 88464 <br />