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following chemicals... ; agricultural; etc.). Describe the general size of the system, the <br />number of such systems, the number of houses to be served (if applicable), or the <br />number of animals or humans the system(s) are expected to serve. <br />No waste materials will be discharged into the ground. <br />c. Water runoff (including stormwater): <br />1) Describe the source of runoff (including storm water) and method of collection <br />and disposal, if any (include quantities, if known). Where will this water flow? <br />Will this water flow into other waters? If so, describe. <br />As required by the City of Everett drainage code, stormwater falling on the site <br />will be collected in storm collection and conveyance systems and will flow <br />through Ecology -approved oil -water separators and StormFilterTM water treatment <br />facilities before discharging to a new manhole to be placed on the existing storm <br />drainage lines upstream of the existing outfalls described below. Flows from <br />portions of the south basin will flow through low impact development rain <br />gardens before entering the south basin collection system. <br />The project will rely on two existing 12-inch diameter stormwater outfalls for <br />discharge of stormwater to the Snohomish River as shown on the <br />grading/drainage plan. Because the outfalls will be used as they currently exist, <br />and no improvements to the outfall structures are proposed, flows draining to the <br />outfalls will need to be metered to match the capacity of the subject outfall. The <br />site has been divided into two tributary areas sized in accordance with the 25-year <br />storm capacity of the outfall they flow to, with flows thereto attenuated by <br />stormwater detention ponds within the two drainage basins. <br />2) Could waste materials enter ground or surface waters? If so, generally describe. <br />Petroleum products, antifreeze, and other automotive -related materials could be <br />spilled on paved surfaces and washed into surface waters running off the site. <br />3) Does the proposal alter or otherwise affect drainage patterns in the vicinity of the site? If <br />so, describe. <br />No. <br />d. Proposed measures to reduce or control surface, ground, and runoff water, and drainage <br />pattern impacts, if any: <br />See the narrative in paragraph c.1 above with regard to stormwater quality <br />measures to be employed. <br />4. Plants <br />SEPA Environmental checklist (WAC 197-11-960) July 2016 Page 7 of 17 <br />