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Ulm loams (5-9% slopes) are located in a thin linear band running from south to north below the Brantner Ditch in the fill area. This map unit consists of a heavy loam topsoil seven inches thick underlain by silty clay, clay, and clay loam to four feet. The Ulm series is not listed as hydric by the U.S. Army Corps of Engineers (1987). Nunn clay loam (1-3% slopes) is found in a narrow linear band topographically below the Ulm loams and above the Brighton Ditch at the toe of the terrace slope. Nunn soils are formed in alluvial material and typically have a loam surface horizon six inches thick. The surface horizon is underlain by clay, loam and silty loam to four feet. Nunn series soils are not listed as hydric (USAGE, 1987) Wet alluvial land is located immediately east of and topographically below the Brighton Ditch along the east boundary of the site. This soil type is found on or near level bottomlands next to stream channels. The materials that make up this soil type are extremely variable and include stratified layers of dark-colored silt, loam, and clay. The layers are generally less than six inches thick and are underlain by sand, fine sand, and some gravel at depths of one to three feet. STUDY METHODS Aggregate Industries provided Savage and Savage with a map that identified and located the area of interest and adjacent surrounding areas. Upon arrival at the site, the study area boundaries were driven and walked, and the character of the area 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 are 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 characteristics indicating anaerobic conditions, and (3) a prevalence of vegetation typically adapted to areas of wetland hydrology and soils. Dominant individual plant species were identified, and their wetland indicator status was assessed at each potentially jurisdictional wetland (USFWS, 1988). Evidence of the hydrologic regime at the sample point was collected and evaluated. Soil units were identified from the Soil Conservation Service (USDA, 1974). Color photographs of the potential wetlands were taken and are being maintained in the permanent data file, with relevant photographs included in the Figures section of this report. Tucson Project Fill Area: Jurisdictional Wetland Delineation and Determination Page 3