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EXHIBIT B: NEW CHAPTER 927 <br />consistent with Rainwater and Land Development shall be utilized during <br />the construction phase and until the site is deemed permanently stabilized <br />by the City of North Olmsted. <br />The skimmer shall be designed per the equivalent requirements of <br />sediment basins and the operator must ensure that the outlet structure of <br />the pond provides an equivalent or better sediment storage zone and <br />dewatering zone. As such, temporarily while the site is under construction, <br />there shall be no discharge of runoff below the elevation required for the <br />sediment storage zone and the discharge of stormwater within the <br />dewatering zone shall only occur through the skimmer. <br />The volume of the sediment storage zone shall be calculated by one of the <br />following methods: <br />Method 1: The volume of the sediment storage zone shall be <br />1 OOOft3 per disturbed acre within the watershed of the basin. <br />Method 2: The volume of the sediment storage zone shall be the <br />volume necessary to store the sediment as calculated with RUSLE <br />or other generally accepted erosion prediction model. <br />When determining the total contributing drainage area, off-site areas and <br />areas which remain undisturbed by construction activity must be included <br />unless runoff from these areas is diverted away from the sediment settling <br />pond and is not co -mingled with sediment -laden runoff. The depth of the <br />dewatering zone must be less than or equal to five (5) feet. The <br />configuration between the inlets and the outlet of the sediment -settling <br />pond must provide at least two units of length for each one unit of width > <br />2:1 length -to -width ratio; however, a length to width ratio of > 4:1 is <br />recommended. Sediment must be removed from the sediment -settling <br />pond when the design capacity of the sediment storage zone has been <br />completely filled by sediment accumulations. This limit is typically <br />reached when sediment occupies one-half of the basin depth. When <br />designing sediment settling ponds, the applicant must consider public <br />safety, especially as it relates to children, as a design factor for the <br />sediment basin and alternative sediment controls must be used where site <br />limitations would preclude a safe design. The use of a combination of <br />sediment and erosion control measures in order to achieve maximum <br />pollutant removal is encouraged. <br />(3) Silt fence and diversions. Sheet flow runoff from denuded areas shall be <br />intercepted by silt fence or diversions to protect adjacent properties and water <br />resources from sediment transported via sheet flow. Where intended to provide <br />sediment control, silt fence shall be placed on a level contour and shall be capable <br />of temporarily ponding runoff. The relationship between the maximum drainage <br />