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Soils Soils within the area of interest are representative of their genesis and topographic position The Natural Resource Conservation Service (USDA, 1974) identifies four soil map units within the project site. The soil units identified aze wet alluvial land, loamy alluvial land (gravelly substratum and moderately wet), and sandy alluvial land. Wet alluvial land is located immediately east of and topographically below the Brighton Ditch along the west boundary of the site. This soil type is found on or neaz level bottomlands next to stream channels. The materials that make up this soil type aze extremely variable and include stratified layers of dazk-colored silt, loam, and clay. The layers aze generally less than six inches thick and are underlain by sand, fine sand, and some gravel at depths of one to three feet. Loamy alluvial land, including the gravelly substratum and moderately wet soil types, dominate the majority of the site. The loamy alluvial land gravelly substratum type is found within major drainageways. It is a principal source of gravel. Nearly all aeeas are subject to flooding. The soils aze shallow and stratified. The strata aze of moderately coarse textured to moderately fine textured material that is underlain by river sand and gravel. The areas of moderately wet soils aze broad in the lazger and more gently sloping drainageways, especially the South Platte River bottom. All areas of this soil type aze subject to flooding. The soils are moderately deep, ranging from 20 to 36 inches in depth, over unconsolidated sand and gravel. Loamy alluvial land moderately wet soils aze dazk- colored loam to clay loam in texture and generally stratified. Sandy alluvial land is located within the southwest comer of the T ucsen project site. This soil type consists of accumulations of gravelly and sandy alluvium Sandy alluvial land is stratified due to periodic flooding. STUDY M, ETHODS Aggregate Industries provided Savage and Savage with a map that identified and located the area of interest and adjacent surrounding aeeas. Upon arrival at the site, the study azea bounda~~ies were driven and walked, and the character of the azea was established. After establishing the boundaries and reference points for mapping purposes, a jurisdictional wetland delineation was conducted. The survey and delineation were conducted in accordance with the requirements of the U.S. Army Corps of Engineers Wetlands Delineation Manual {USAGE, 1987). To determine the areas aze subject to Corps jurisdiction, three criteria were evaluated: {1) evidence of a hydrologic regime reflecting saturation or periodic inundation by surface or ground water of sufficient duration and frequency, {2) soils which are considered hydric by classification or field chazacteristics indicating anaerobic conditions, and (3) a prevalence of vegetation typically adapted to areas of wetland hydrology and scils. Tucson Projeci Jurisdictional Vl/etland Delineation and Determination Page 3