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2.0 EXISTING CONDITIONS SUMMARY <br />Pre -Developed Site Conditions <br />The site is currently developed with an existing gas station, convenience store, fast food <br />restaurant, and car wash, as well as a parking lot. The convenience store and restaurant <br />are the same building in the center of the site; the gas pumps are on the east, and the <br />car wash facility is on the west. <br />Topography <br />The site is relatively flat with slopes less than 5%. <br />Land Cover <br />The site is developed and primarily covered with hard surface and landscaping. <br />Adjacent Land Uses <br />The site is bounded as follows: <br />North: Commercial (Zoned C-1) <br />West: Commercial/Residential (Out of City Limits) <br />East: Commercial (Zoned C-1) <br />South: 132"d Street SE (Public) <br />Native Soils <br />The United States Department of Agriculture Natural Resource Conservation Service <br />(NRCS) identifies Alderwood-Urban land complex (5) underlying most of the project site. <br />This soil is identified as part of the hydrologic soil group B which is conducive to infiltration. <br />Groundwater is noted typically at depths between 18-36 inches. <br />McKenna gravelly silt loam (32) is also identified on a portion of the site. This soil is in <br />hydrologic soil group D. Groundwater is noted typically at depths between 0-6 inches. <br />A geotechnical report for this site is provided by Pangeo. This report can be found in <br />Appendix B. The following is their characterization of the infiltration capabilities of the site: <br />"The native soils underlying the site consist of Vashon till, a dense to very dense deposit <br />comprised of clay, silt, sand, and gravel. Till is generally not a suitable receptor soil for <br />infiltration due to the high fines content and density. Where loosened by weathering <br />infiltration rates of about 1/2 inch per hour may be obtained. Where unweathered, <br />infiltration rates are typically less than 1/4 inch per hour. Perched groundwater, which can <br />limit infiltration, also develops in till soils during wet season at the transition from <br />weathered to unweathered soils. In summary, it is our opinion that non -infiltration <br />alternatives should be considered to manage the surface runoff at the site." <br />Drainage Patterns <br />Currently stormwater runoff is collected by catch basins in the parking lot and routed <br />northeast through the private drainage system. There is an existing oil -water separator <br />