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<br />such sedimentation and erosion control devices and practices as are <br />sufficient to retain the sediment generated by the land-disturbing activity <br />within the boundaries of the tract during construction upon and <br />development of said tract, and shall plant or otherwise provide a <br />permanent ground cover sufficient to restrain erosion after completion of <br />construction or development. Except as provided in Section 8 (D) (2) (e) of <br />this ordinance, provisions for a ground cover sufficient to restrain erosion <br />must be accomplished within 30 working days or 120 calendar days, <br />whichever period is shorter, fallowing completion of construction or <br />development. <br />D. Design and Performance of Control Measures <br />1. Design Storm <br />Except as provided in Section 8(D)(2)(b) of this Ordinance and in the <br />standard for sediment ponds in the Soil Erosion and Sediment Control <br />Manual erosion and sedimentation control measures, structures, and <br />devices shall be so planned, designed, and constructed as to provide <br />protection from accelerated erosion and sedimentation from the calculated <br />maximum peak rates of runoff from the ten-year frequency storm. Runoff <br />rates shall be calculated using the procedures in the USDA Soil <br />Conservation Service's "National Engineering Field Manual for <br />Conservation Practices," or other calculation procedures acceptable to the <br />Erosion Control Officer. <br />2. Standards for High Quality Waters <br />In High Quality Water (HQW) zones the following design standards shall <br />apply: <br />a. Uncovered areas in HQW zones shall be limited at any time to a <br />maximum total area of 20 acres within the boundaries of the <br />tract. Only the portion of the land-disturbing activity within a <br />HQW zone shall be governed by this section. Larger areas may <br />be uncovered within the boundaries of the tract with the written <br />approval of the Director of the Division of Land Resources of the <br />Department of Environment, Health, and Natural Resources. <br />b. Erosion and sedimentation control measures, structures, and <br />devices within HQW zones shall be so planned, designed, and <br />constructed to provide protection from the runoff of the 25-year <br />storm which produces the maximum peak rate of runoff. The <br />peak rate of runoff shall be calculated according to procedures in <br />the United States Department of Agriculture Soil Conservation <br />Service's National Engineering Field Manual for Conservation <br />Practices or according to procedures adopted by any other <br />agency of this state or the United States or any generally <br />recognized organization or association. <br />G:\EROSION\Amendments\AMENDS2001.doc <br />