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Appendix 2 <br />Method 2 for Quantifying TN Export from Residential / Industrial / Commercial <br />Developments when Footprints of all Impervious Surfaces are Shown <br />Step l: Determine area for each type of land use and enter in Column <br />(2)• <br />Step 2: Total the areas for each type of land use and enter at the bottom of Column (2). <br />Step 3: Multiply the areas in Column (2) by the TN export coefficients in Column (3) and <br />enter in Column (4). <br />Step 4: Total the TN exports for each type of land use and enter at the bottom of Column (4). <br />Step 5: Determine the export coefficient for site by dividing the total TN export from uses at <br />the bottom of Column (4) by the total area at the bottom of Column (2). <br />(1) (2) <br />(3) <br />(4) <br />Type of Land Cover Area <br />TN export <br />TN export from <br />coeff. <br />use <br />acres <br />Ibs /ac/ r <br />Ibs/ r <br />Permanently protected undisturbed <br />0.6 <br />open s ace (forest, unmown meadow) <br />Permanently protected managed <br />1.2 <br />open s ace (grass, landscaping, etc. <br />Impervious surfaces (roads, parking <br />21.2 <br />lots, driveways, roofs, paved storage <br />areas, etc. <br />TOTAL <br />--- <br />The rule requires that all new developments achieve a nitrogen export of less than or equal to 3.6 <br />pounds per acre per year. If the development contributes greater than 3.6 lbs /ac /yr of nitrogen, <br />then the options shown in Table 2a are available based on whether the development is residential <br />or non - residential. <br />M <br />