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I <br /> Element 10:Control De-Watering <br /> • De-watering is not anticipated as part of this project. <br /> • Foundation, vault, and trench de-watering water, which has similar characteristics to <br /> stormwater runoff at the site, shall be discharged into a controlled conveyance system prior <br /> to discharge to a sediment trap or sediment pond. Channels must be stabilized, as specified <br /> in Element#8. <br /> • Clean, non-turbid de-watering water, such as well-point ground water, can be discharged to <br /> systems tributary to state surface waters,as specified in Element#8, provided the de- <br /> watering flow does not cause erosion or flooding of receiving waters. These clean waters I <br /> should not be routed through a stormwater sediment pond. <br /> • Highly turbid or otherwise contaminated dewatering water, such as from construction <br /> equipment operation, clamshell digging, concrete tremie pour, or work inside a cofferdam, <br /> shall be handled separately from stormwater. <br /> • Other disposal options, depending on site constraints, may include: 1) infiltration, 2) <br /> transport off-site in a vehicle, such as a vacuum flush truck, for legal disposal in a manner <br /> that does not pollute state waters, 3) Ecology-approved on-site chemical treatment or other <br /> suitable treatment technologies, 4) sanitary sewer discharge with local sewer district <br /> approval, if there is no other option, or 5) use of a sedimentation bag with outfall to a ditch <br /> or swale for small volumes of localized dewatering. <br /> Element 11: Maintain BMPs <br /> • All temporary and permanent erosion and sediment control BMPs shall be maintained and <br /> repaired as needed to assure continued performance of their intended function. All <br /> maintenance and repair shall be conducted in accordance with BMP specifications. <br /> • All temporary erosion and sediment control BMPs shall be removed within 30 days after <br /> final site stabilization is achieved or after the temporary BMPs are no longer needed. <br /> Trapped sediment shall be removed or stabilized on site. Disturbed soil areas resulting from <br /> removal of BMPs or vegetation shall be permanently stabilized. <br /> Element 12:Manage The Project I <br /> • Coordination with Utilities and Other Contractors-The primary project proponent shall <br /> evaluate, with input from utilities and other contractors, the stormwater management <br /> requirements for the entire project, including the utilities, when preparing the Construction <br /> SWPPP. <br /> Inspection and Monitoring-All BMPs shall be inspected, maintained, and repaired as <br /> needed to assure continued performance of their intended function. Site inspections shall <br /> be conducted by a person who is knowledgeable in the principles and practices of erosion <br /> and sediment control. The person must have the skills to 1) assess the site conditions and �. <br /> construction activities that could impact the quality of stormwater, and 2) assess the <br /> effectiveness of erosion and sediment control measures used to control the quality of <br /> stormwater discharges. <br /> • A Certified Erosion and Sediment Control Specialist shall be identified in the Construction <br /> SWPPP and shall be on-site or on-call at all times. <br /> Whenever inspection and/or monitoring reveals that the BMPs identified in the I <br /> Construction SWPPP are inadequate, due to the actual discharge of or potential to <br /> 6/16/2011 Stormwater Site Plan Page 14 <br />