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Infiltration will not be permitted and alternative practices will be required in the 10 year capture <br />zone of the DWSMA. Soils with infiltration rates of more than 8.3 inches per hour must be <br />amended to reduce the infiltration rate to less than 8.3 inches per hour. Infiltration will also be <br />prohibited in the following areas: <br />a. Where industrial facilities are not authorized to infiltrate industrial stormwater under an <br />NPDES /SDS Industrial Stormwater Permit. <br />b. Where vehicle fueling and maintenance occur <br />c. With less than three (3) feet of separation distance from the bottom of the infiltration system to <br />the elevation of seasonally saturated soils or the top of bedrock <br />d. Where high levels of contaminants in soil or groundwater will be mobilized by the infiltrating <br />stormwater <br />(e) All calculations and information used in determining these peak storm discharge rates shall be <br />submitted along with the stormwater pollution control plan. <br />The applicant shall consider reducing the need for stormwater management facilities b., irporating <br />the use of natural topography and land cover such as natural swales and depressions as they exist before <br />development to the degree that they can accommodate the additional flow of treated (e.g., settled) water <br />without compromising the integrity or quality of the wetland or pond. <br />The following stormwater management practices must be investigated in developing the stormwater <br />management part of the stormwater pollution control plan in the following descending order of <br />preference: <br />(1) Protect and preserve as much natural or vegetated area on the site as possible, minimizing <br />impervious surfaces, and directing runoff to vegetated areas rather than to adjoining streets, storm <br />sewers and ditches; <br />(2) Flow attenuation of treated stormwater by use of open vegetated swales and natural depressions; <br />(3) Stormwater wet detention facilities (including percolation facilities); and <br />(4) A combination of successive practices may be used to achieve the applicable minimum control <br />requirements specified in subsection (a) of this section. The applicant shall provide justification for <br />the method selected. <br />(f) <br />(g) <br />(i) <br />(h) The stormwater controls for new development sites shall also provide no net increase in stormwater <br />discharges of Total Suspended Solids (TSS) and Total Phosphorus (TP). <br />The stormwater controls for redevelopment projects shall achieve a net reduction from pre - project <br />conditions (on an annual average basis) of: <br />(1) Stormwater Discharge Volume <br />(2) Stormwater Discharges of TSS <br />(3) Stormwater Discharges of TP <br />The City will evaluate requests for a variance to the volume reduction goals when site conditions <br />preclude infiltration. The developer shall implement to the maximum extent practicable other volume <br />reduction techniques on site. The Lower Rum River Watershed Management Organization has adopted <br />procedures for making a financial contribution when volume reduction goals cannot be met. The <br />variance approval and financial contribution calculations will become part of the permanent project <br />record retained by the City. <br />(j) <br />