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RECEIVED <br /> Rifle Gravel Pit #1 IJUL 19 2023 July 2023 <br /> ('nlnrorin niviciop Qi F�e6ldnteirvt+, <br /> Mining and Saftey <br /> 11.0 Exhibit J — Vegetation Information <br /> Figure 5, Exhibit C3 depicts the location and types of vegetation at the mining site. Figure <br /> 6 through Figure 8 show photos from the property. <br /> Vegetation in the Affected Lands is a mix of upland pasture and partially irrigated pasture. <br /> The partially irrigated pasture areas are subject to an inconsistent and uneven application of <br /> irrigation water via flood irrigation and subsurface seepage, primarily from uncontrolled <br /> discharges and return flows from adjacent irrigation operations. Intentional irrigation water <br /> application on the site has not occurred since the property was acquired by Scott. The <br /> extent of the Affected Lands has been carefully restricted to areas of mesic soil conditions <br /> and avoids nearby areas of hydric soils that support emergent wet meadows. A small <br /> portion of the Affected Lands contains sparse riparian woodland, consisting entirely of non- <br /> native Russian olive (Elaeagnus angustifolia) with a sparse shrub understory. There are no <br /> native trees (cottonwoods, Populus deltoides) within the Affected Lands. <br /> The observed vegetation within the Affected Lands does not precisely match the data <br /> provided by the National Land Cover Database given the large cell size of the NLCD data. <br /> Vegetation conditions on the property and the immediate vicinity were categorized based on <br /> aerial imagery and familiarity with the site, then hand-digitized for display as shown on <br /> Figure 5, Exhibit C3. <br /> 11.1 Existing Vegetation Communities <br /> The existing vegetation found on the Rifle Gravel Pit Permitted Area consists primarily of <br /> upland pastures, with a small component of riparian woodland/shrubland dominated by <br /> Russian olive (Elaeagnus angustifolia). Outside of the Permitted Area, the property also <br /> includes wet meadows and wetlands/marshes. Dominant species that typify each <br /> community are listed below. The entire property supports generally continuous ground <br /> coverage of>80% throughout, and standing biomass and productivity are relatively high for <br /> the surrounding region. <br /> Noxious weeds observed at the property include cheatgrass (Bromus tectorum), Russian <br /> olive, chicory (Cichorium intybus), halogeton (Halogeton glomeratus), Russian knapweed <br /> (Acroptilon repens), and bulbous bluegrass (Poa bulboua). The weed species constitute a <br /> significant portion of the vegetation in upland pasture areas within the property, but <br /> generally were not observed to form monotypic stands or to present an unusual risk of <br /> infestation. The weed component and prevalence on the property is typical of grazed <br /> pasturelands in the surrounding area. <br /> A comprehensive noxious weed survey has been completed for the property, and it is likely <br /> that other common weeds in the surrounding area would be found in a dedicated search, <br /> including hoary cress (Cardaria draba), field bindweed (Convolvulus arvensis), common <br /> mullein (Verbascum thapsus) and several thistle species. A copy of the Noxious Weed <br /> Report is included in Attachment C. <br /> Vegetation types, quantitative cover estimates, and relationship to soil types were based on <br /> a comprehensive wetland delineation that was performed for the property at the request of <br /> the USACE. This comprehensive delineation effort was based on the direct measurement of <br /> vegetation, soil, and hydrology conditions along regularly spaced transects, resulting in a <br /> sample grid of 183 points spaced at 100-foot intervals, covering the entire Affected Lands <br /> and the majority of the parcel as well. <br /> 68 <br />