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Nick DeBar May 27, 2011 Page 2 G:\SMK\Moundsview Contract\Mounds View Pond Inventory.docx Task A---Data Gathering……………………………………………………………………$4,400 • Develop a file of any drawings and other information the City may have on the basin (Performed by the City) • Determine the immediate drainage area and the total tributary area to the basin (Performed by Barr) • Perform a bathymetric elevation survey of the basin. The survey information collected will be limited to the minimum amount of survey shots needed to determine a reasonably accurate bathymetric map of the basin bottom in order to estimate the basin’s volume (Performed by Barr) • Determine historic wetland status for the site by obtaining and reviewing NWI, soils maps/data and historic aerial photos in the area of the basin that were prepared/taken prior to the time it was constructed or storm sewers were constructed to discharge into it. (Performed by Barr) • Take photos and measurements of the basin’s outlet structure and photograph other in-basin structures if any (Performed by Barr) Task B--- Basin Maintenance Computations and Prioritization……………………...$2,550 • Prepare a an existing conditions contour drawing for the basin (Performed by Barr) • Estimate the volume of sediment to be removed from the basin based on a) if the basin or parts of it was a wetland prior to its construction (proposed excavation can only be as deep as the top of the remaining original wetland material), b) records of how deep the basin was originally constructed or c) excavation needed to optimize the basin’s performance per Minnesota Stormwater Manual criteria (Performed by Barr) • Prepare opinions of cost for a) excavation and disposal/reuse of dredged sediment, b) structure modifications that may be needed to improve basin performance (Performed by Barr) • Prepare an estimate of the anticipated percent removal of total suspended soils and total phosphorous that the basin may be able remove, base d on the size of the basin (relative to its total drainage area) for existing and proposed conditions (Performed by Barr) Task C--- Basin Maintenance Summary Report……………..….$3,000 • Prepare a report summarizing the work performed, analysis findings, projected basin efficiencies (current and future), maintenance costs, and recommended actions based on the work described above. Barr will provide the City two hard copies and an electronic PDF of the project report • Present the report to the City staff (Performed by Barr) Please note that in each task the design and management of any dredging or other construction work is not included in our estimated costs, as it is not yet known what work will be needed.