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Mr. Fossum reviewed detailed construction drawings for the project area to direct the drainage area to address annual phosphorus contributions, correct the erosion to the inlet, address a small gully, and other historical issues that had developed over the years. Mr. Fossum noted that this area drains forty (40) acres and was owned by the Armory, with an easement by the City of Roseville. Mr. Fossum reviewed capacity and management data and comparisons over several years, and anticipated goals to be achieved through this retrofit project. Mr. Fossum further reviewed engineer's estimates for the project as detailed in the report, and cost -share between CRWD, Ramsey Conservation District (RCD) and the City of Roseville, with Wenck and Associates under contract with the CRWD for project engineering. Mr. Fossum reviewed the components of the preliminary engineering that included soil borings and bottom sampling with the summary indicating clayey sands, loan and dense clay and peat, creating poor soils for infiltration, requiring other options to be considered to meet Minnesota Wetland Design Issues through the Water Conservation Act. Todd Shoemaker Mr. Shoemaker reviewed the construction plans in detail, addressing existing conditions; trees to be preserved and a limited number to be removed to facilitate the project; and reviewed the proposed three pronged practices or techniques: Pretreatment to capture large core sediment before entering the pond Excavate pond back to its design scenario; pond excavated to 1991 elevations Iron enhanced filtration bench Mr. Shoemaker reviewed the technology treatment of iron filings developed by the University of Minnesota over the last few years and successful trials beyond those found with previous steel wool treatment in reducing dissolved phosphorus. Mr. Shoemaker illustrated the process 'j` for installation of a weir in the outlet structure to force water laterally through the filtration bench (rock and iron filings), and then through the drain tile. Mr. Shoemaker clarified that the iron filings were clean iron filings, a by- product of some other mechanism that were broken down for re -use; with the only supplier at this time in Chicago, requiring shipment to the metropolitan area, while several local firms in Minnesota are discussing development of this technology locally. Mr. Shoemaker noted that the engineer's estimate for the base bid was approximately $66,000 for the project, with total project costs broken down, and based on pond maintenance, by the three (3) partners as follows: Ms. Bloom noted that the engineering costs would be covered by the CRWD; and construction costs shared by the three partnering agencies: Ramsey Conservation District (RCD); City of Roseville; and Capitol Region Watershed District (CRWD). Page 2 of 11