1910 112TH ST SW RIVERSTONE SITE DEV 2016-01-01 MF Import

cemented hardpan i> at a depth of about 35 inches. Permeability of this soil is moderately rapid above the hardpan and very slow through it. Available water capacity is low. Hydrology Criteria The Washington State Wetlands Identification and Delineation Manual, 19?7 edition, states that "areas which are seasenalty inundated and/or saturated to the surface for a consecutive number oi days greater than or equal to 12.590 of the growing season are wetlands, provided the soil and vegetation parameters are met. Areas inundated or saturated between 5 and 12.5% of the growing season in most years may or may not be wetlands. Areas saturated to the surface for less than 5% of the growing season are non•wetlands." Field indicators are used for determining whether the wetland hydrology parameter is met. BOUNDARY DETERMINATION FINDINGS Wetland A, Category II This riparian wetland associated witn a tributary of Swamp Creek is located off•site to the south and west. Vege[ation in this wetland is represented by red alder (Alnus rubra, Fac) and Pacific willow (Solix lucido, FacW+) in the canopy, with hardhack (Spir^aa douglosii, FacW), skunk cabbage (Lysichiton omericonum, Obl), slough sedge (Carex obnup[a, Obl), and creeping buttercup (Ranunculus repens. FacW) in the understory. Soils in this wetland have a Munsell color of black (10 YR 2/1) with redoximorphic features of brown (10 YR 5/3) and a texture of silt loam from 0 to 18 inches below the surface. At the time of site investigation (October 2003►, soils in this wetland were found to be moist. Wetland B, Category III This Category III wetland is located east of the subject site. Vegetation i i this w•etland is represented by Pacific wiUow and Sitka willow (Salix sitchensis, FacW) in the canopy, with an understory comprised of salmonberry (Rubus spectabilis, Fac*�, hardhack, biack twinberry (Lonicero involucrata, Fac+), slough sedge, skunk cabbage, climbing nightshade (Solanum dulcomarn, Fac+), and sword fern (Polystichum munitum, FacUl growing on hummocks. Soils in this wetland have a Munsell color of very dark grayish brown (10 YR 3/2) with redoximorphic features of yellowish brown (10 YR 5/6) and a texture of silt loam from 0 to 6 inches below the surface. From 6 to 18 inches below the surface, soils have a MunseU color of very dark �ray (10 YR 3/1) with redoximorphic features of dark yellowish brown (10 YR 4/6� and a texture of silt loam. At the time of site investigation (October 2003), soils in this wetland were found to be moist. It appears tha[ the areas mapped as wetland are fluoded, ponded, or saturated long enough during the growing season to develop anaerobic conditions in the upper part of the soil. The wetland areas appear to b�� saturated to the surface for a consecutive number of days greater than er equal to 12.5% of the growing a 3 �'