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b. Ground Water: <br /> 1) Will groundwater be withdrawn from a well for drinking water or other purposes? If so, <br /> give a general description of the well, proposed uses and approximate quantities <br /> withdrawn from the well. Will water be discharged to groundwater? Give general <br /> description, purpose, and approximate quantities if known. No <br /> 2) Describe waste material that will be discharged into the ground from septic tanks or <br /> other sources, if any (for example: Domestic sewage; industrial, containing the <br /> 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. Not Applicable <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. The existing trench drain <br /> system ties into an onsite conveyance system that includes five flow splitters <br /> that allow the water quality treatment storm flowrate to continue downstream to <br /> the onsite water quality treatment system. Flows that exceed the water quality <br /> treatment flowrate discharge directly to Merrill Creek. This project will redesign <br /> and reconstruct the five flow splitters to continue to direct flows up to the water <br /> quality flowrate to the onsite water quality treatment system. Flows in excess of <br /> the water quality treatment flowrate will overtop a weir and discharge out to <br /> Merrill Creek. The majority of onsite pollutants are collected in the more frequent <br /> smaller storm events and thus end up in the water quality treatment <br /> system. Runoff from storm events in excess of the water quality treatment storm <br /> consists mostly of clean rainwater. The new flow splitter structures will be made <br /> large enough to accommodate a downturned elbow on the pipe discharging to <br /> Merrill Creek which acts to keep oils and other floatable debris inside the <br /> structure rather than discharging to Merrill Creek. The existing outfall locations <br /> will be maintained with slight modifications to the elevations. <br /> 2) Could waste materials enter ground or surface waters? If so, generally describe. No <br /> 3) Does the proposal alter or otherwise affect drainage patterns in the vicinity of the site? If <br /> so, describe. No. The project does not add impervious surfacing or incorporate <br /> new drainage areas so there is no change to the flow rate or quantity being <br /> directed to the flow splitters and discharging to Merrill Creek. <br /> d. Proposed measures to reduce or control surface,ground, and runoff water, and drainage <br /> pattern impacts, if any: This maintenance project will improve the effectiveness of the <br /> stormwater management system. <br /> 4. Plants <br /> a. Check the types of vegetation found on the site: <br /> _X_deciduous tree: alder, maple, aspen, other <br /> _X evergreen tree: fir, cedar, pine, other <br /> X shrubs <br /> SEPA Environmental checklist(WAC 197-11-960) July 2016 age 9 of 15 <br />