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Methodology The Jurisdictional Delineation was conducted following the methodology enumerated in the 1987 Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory, 1987). During the field inspection, representative soil borings were taken, dominant vegetation was recorded and representative hydrologic indicators were noted in order to identify and document the presence of jurisdictional waters of the U.S., including wetlands within the foot-print of the proposed sand and gravel operation on the property. Potentially jurisdictional areas were flagged in the field, labeled with an alphanumeric designation, and surveyed by a Professional Licensed Surveyor (PLS) and a Global Positioning System. Because there was little variation in the vegetation communities, sampled soils, and characteristics within each area, WALSH determined that one representative data point would be sufficient to record conditions in each area (refer to attached datasheets). Other data points were taken at vazious points throughout the site to confirm the first representative point remained valid. Waters and wetlands on or immediately adjacent to the site were characterized. However, because they are not subject to impact from the proposed project or were isolated, they were not formally delineated or surveyed. However, these areas were mapped using aerial photography and proofed in the field following the methodology enumerated in the 1987 Manual. These areas have been provided for reference on Figure 2. Soils Representative soil borings were taken in each potential wetland area to determine the presence or absence of hydric soils, and in adjacent uplands to document the absence of hydric conditions (refer to attached Data Sheets). A visual inspection of the soil profile analyzed for the presence of hydric soil characteristics (e.g., mottling, oxidized roots, concretions and/or gleying). Soil hue, value, and chroma were compared to the Munsell Soil Color Charts (Kollmorgen, 1990) to determine the presence ofhydric soils. The Soil Survey ofR j7e.4rea, Colorado (U.S. Soil Conservation Service, 1985) was referenced for the soil types occurring at the sites. Within the project area, one general soil-mapping unit occurs, the Arvada-Tomfluvents-Heldt complex. This map unit contains deep, well drained to somewhat poorly drained, neazly level to gently sloping soils on benches, terraces, alluvial fans and floodplains. Heldt soils have not been mapped on this site and are replaced by Wann soils as described below. These soils are typically used for irrigated crops, grazing, and wildlife habitat. Major crops aze alfalfa, small grains and irrigated pasture. On site, the Arvada series (3) is directly correlated with the upper most terrace located adjacent to the railroad corridor. The clayey and highly saline soil characteristics and vegetation documented in the USDA Soil Survey is consistent with those observed on site. This area of the site is dominated by greasewood with a minor grass component. This portion of the site is not used as irrigated pasture.