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2.1.4 Element 4: Install Sediment Controls <br /> All stormwater runoff from disturbed areas shall pass through appropriate sediment removal <br /> BMPs before leaving the construction site. BMPs will be constructed as one of the first steps of <br /> grading and will be functional before other land disturbing activities take place. <br /> In addition, sediment will be removed from paved areas in and adjacent to construction work <br /> areas manually or using mechanical sweepers, as needed, to minimize tracking of sediments on <br /> vehicle tires away from the site and to minimize washoff of sediments from adjacent streets in <br /> runoff. <br /> When permanent stormwater BMPs will be used to control sediment discharge during <br /> construction, the structure will be protected from excessive sedimentation with adequate erosion <br /> and sediment control BMPs. Any accumulated sediment shall be removed after construction is <br /> complete and the permanent stormwater BMP will be restabilized with vegetation per applicable <br /> design requirements once the remainder of the site has been stabilized. <br /> Applicable BMPs: <br /> • BMP C200: Interceptor Dikes and Swales <br /> • BMP C207: Check Dams <br /> • BMP C220: Storm Drain Inlet Protection <br /> • BMP C233: Silt Fence <br /> • BMP C241: Sediment Pond <br /> A sediment pond will be utilized for the majority of the onsite disturbed area. The surface area <br /> for the sediment pond is determined by calculating the runoff rate of the 10-year return period <br /> developed storm event using the city of Everett design guidelines. Though Phase 1 only <br /> includes 8.43 Ac, the sediment pond will be sized to handle flows from the combined area of <br /> Phase 1 and 2 (10.73 Ac). <br /> The area calculated to be tributary to pond A is 10.73 acres and will be composed of an <br /> estimated 85% impervious coverage. The required sediment pond area was determined using <br /> the City of Everett drainage Manual, relevant equations,tables, coeffecients, and methodology <br /> are included in Appendix H. The sediment pond is designed to accommodate the 10 yr <br /> recurrence interval flow. See Appendix B for TESC details. <br /> Page � 9 <br />