2018-05-22_PERMIT FILE - M2018027 (4)

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Pmy©n Engineers(USACE)based on percentages representing the frequency that a species occurs in a wetland (Lichvar et al. 2012). Wetland species are ranked: • obligate (OBL), occur almost always under natural conditions in wetlands (99%); • facultative wetland (FACW), usually occur in wetlands but occasionally found in non-wetlands (67- 99%); • facultative (FAC), equally likely to occur in wetlands and non-wetlands (34-66%); • facultative uplands (FACU), usually occur in non-wetlands but occasionally found in wetlands (1-33%); • and upland (UPL), may occur in wetlands in another region, but occur almost always under natural conditions in non-wetlands in the region specified (I%) (Lichvar et al., 2012; Lichvar et al., 2016). Any ranking of FAC or higher is considered potential wetland vegetation.Wetland vegetation indicator ratings vary region to region; based on the location of the study area the Great Plains Region vegetation indicators were used. Results General Habitat The majority of the study area consists of fallow and seeded sod fields and upland vegetation (Photos I and 2 in the Photographic Log). Numerous man-made irrigation ponds and irrigation ditches are located throughout the study area. Wetland vegetation is present in narrow fringes around the man-made ponds. The dominant land type/use in and adjacent to the study area is cropland and pastureland associated with rural agricultural properties. Some structures related to oil and gas production, as well as one commercial business, are also located within the study area. Given the presence of the fallow fields, irrigation ponds and ditches, structures pertaining to oil and gas extraction, and a commercial business within the study area; natural vegetation, soils, and hydrology have been altered by filling, grading, and improvement activities in the past. Most upland areas in the study area are fallow or seeded sod fields. Due to the nature of sod production (i.e., grass is not allowed to go to seed) and because some fields were fallow, grasses were not in a phenological state to positively identify. Based on Green Valley Turf Company's website, grasses in the study area are likely Kentucky blue grass (Poo protensis), Texas bluegrass (Poo arochnifera), tall fescue (Festuca orundinocea), and/or buffalograss (Boutelouo doctyloides) (Green Valley Turf Company, 2018). Based on the vegetative morphology of the species in the study area, tall fescue is likely the species present. Other upland areas in the study area are primarily dominated by the grass smooth brome (Bromus inermis) and numerous weedy species such as Russian thistle (Salsola trogus), redstem stork's-bill (Erodium cicutorium; Colorado Department of Agriculture List C noxious weed, no management required), purple mustard (Chorispora tenella), and shepherd's purse (Copsel/a bursa-pastoris) (CDA, 2018). Wetland areas were identified throughout the study area and wetland vegetation indicators are discussed further below. Federally Listed Species Based on a review of the United Stated Fish and Wildlife Service (USFWS) online Information for Planning and Consultation(IPaC)System,there are nine federally listed species with the potential to occur in,or be impacted by, a project located in Weld County (USFWS, 2018a). Of the nine species,five species are included because they occur downstream of the study area along the Platte and/or Missouri Rivers and could be impacted by projects that would result in water depletions to their tributaries. These five species include the Interior Least Tern (Sternula ontillorum), pallid sturgeon Biological Resources Technical Memorandum Hunt Slurry Wall Proposed Alignment April 23, 2018 2