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I <br /> Stormwater Pollution Prevention Plan <br /> 3.0 Construction Stormwater BMPs <br /> 111 <br /> The following BMP's are included within the Erosion Control/SWPPP shown on sheets C2.01- <br /> C2.02, included in Appendix A of this document. See BMP cut sheets included in Appendix D <br /> of this document. The BMP's will be implemented according to the Construction Sequence <br /> included in section 2.0. <br /> 3.1 TheBMP 12 Elements <br /> 3.1.1 Element#1 —Mark Clearing Limits <br /> To protect adjacent properties and to reduce the area of soil exposed to construction, the limits of <br /> construction will be clearly marked before land-disturbing activities begin. Trees that are to be <br /> preserved, as well as all sensitive areas and their buffers, shall be clearly delineated, both in the <br /> field and on the plans. In general, natural vegetation and native topsoil shall be retained in an <br /> undisturbed state to the maximum extent possible. The BMPs relevant to marking the clearing <br /> limits that will be applied for this project include: <br /> ■ High Visibility Plastic or Metal Fence (BMP C103) <br /> • Preserving Natural Vegetation (BMP C 101) <br /> I . Buffer Zones (BMP C 102) <br /> 3.1.2 Element#2—Establish Construction Access <br /> Construction access or activities occurring on unpaved areas shall be minimized, yet where <br /> necessary, access points shall be stabilized to minimize the tracking of sediment onto public <br /> roads, and wheel washing, street sweeping, and street cleaning shall be employed to prevent <br /> sediment from entering state waters. All wash wastewater shall be controlled on site. The <br /> specific BMPs related to establishing construction access that will be used on this project <br /> include: <br /> ■ Stabilized Construction Entrance (BMP C105) <br /> 3.1.3 Element#3 —Control Flow Rates <br /> Storm water runoff from the site will be directed to multiple sediment traps for storage and <br /> treatment of silt laden water. During the time in which the sediment traps are being constructed <br /> the contractor shall be prepared to bring temporary storm water storage tanks such as Baker <br /> Tanks, or similar to provide temporary storage and avoid discharging turbid water offsite. <br /> I . Sediment Trap (BMP C240) <br /> The project site is located within the Snohomish River watershed, and must comply with <br /> Minimum Requirement 7 (Ecology 2005). In general, discharge rates of stormwater from the site <br /> will be controlled where increases in impervious area or soil compaction during construction <br /> I <br /> I5 <br />