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I <br />A nutrient budget was performed to evaluate the impact of the pollutant loadings to Long Lake <br />from the construction of the golf course. The procedures used in the analysis are from the <br />MPCA's "Protecting Water Quality in Urban Areas, ’’ Best Management Practices Manual. The <br />pollutant concentrations used in determining the loadings for both undeveloped and developed <br />conditions were those representing open/non-urban land use. Although there will be a change <br />in the land use. A 1995 study by Mr. John Barten, of Suburban Hennepin County Park District, <br />on the quantity and quality of golf course runoff found that the nutrient export from golf courses <br />is very similar to undeveloped land. ’ A copy of the entire report is located in appendix H. <br />The removal efficiencies of the proposed NURP basins are based on "Walker ’s” long term <br />NURP basin pond performance criteria. The results of nutrient budget analyses indicate an <br />overall reduction in the pollutant loadings to Long Lake. The nutrient budget data is tabulated <br />be/oiv. <br />TABLE 2 <br />LONG LAKE NUTRIENT LOADING BUDGET <br />Ill#Hi <br />Total Existing <br />Loading <br />(lbs.) <br />Total Proposed <br />Loadir^ to NURP <br />Basins <br />(lbs.)‘ <br />Removal <br />Efficiency Range <br />(%) <br />Total Prooosed <br />Loading ; > Long <br />: Lake <br />(lbs.) <br />Total Suspended <br />Solids (TSS) <br />28.602 38,409 89-98 5.700 - 770 <br />Total <br />Phosphorous (TP) <br />30.46 40.89 40-70 28.6-12.3 <br />Total Kjeldahl <br />Nitrogen (TKN) <br />180.08 241.83 20-40 192-145 <br />Lead (Pb)7 I.-*96 80-95 1.9-0.5 <br />Zinc (Zn)40.89 40-80 24 5-8.2 <br />*The proposed pollutant loadings are based on the additional runoff volumes generated by the proposed greens, <br />fairways and tees. <br />A further reduction in the future pollutant loadings can be expected when the ditch system <br />draining the existing wetlands is removed and new weir structures are installed at the wetland <br />outlets. The new weii structures will impound the runoff (up to a two-foot depth) and allow the <br />water to infiltrate into the ground rather than drain eventually into Long Lake. The impounding <br />of the runoff will not only reduce the pollutant loadings, but will also help partially restore the <br />wetlands to their pre-drained condition. It is anticipated that the average water depth in the <br />wetlands will increase by one foot. <br />’ Barten. John M., Quantity and Quality of Runoff from Four Golf Courses in the <br />Twin Cities Metropolitan Area . September 1995, Suburban Hennepin Regional Park <br />District