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Orchard Mesa Selenium Remediation Environment Assessment 7 Land Use and Vel!:etation The OMW A includes about 153 acres of river bottomland at an average elevation of 4,600 feet. The area is managed as wildlife habitat for local fish and wildlife. The area is surrounded by private agricultural lands. A wetlands delineation was conducted in July 1999 by Reclamation's Technical Service Center in Denver, Colorado (USBR 1999a). The delineation identified nine vegetation community types. The community types are as follows: I. Upstream Bench 2. Upper (Dry) Drainage Ditch 3. Middle Drainage Ditch 4. Lower Drainage Ditch 5. Permanent and Semi-Permanent River Channel and Braids 6. Mature Riparian Woodlands 7. Salt Cedar-Cheatgrass Complex 8. High Flow Channel Complex 9. Spoil Pile Common plant species included Freemont cottonwood (Populusfreemontii), salt cedar (Tamarix chinensis), sandbar willow (Salix exigua), Russian olive (Eleagnus angustifolia), Siberian elm (Ulmus pumila), black greasewood (Sarcobatus vermiculatus), skunkbush sumas (Rhus trilobata), Douglas rabbitbrush (Chrysothamnus viscidiflorus), cheatgrass (Bromus tectorum), saltgrass (Distichlis spicata), wheatgrass (Agropyron spp.), canary reedgrass (Phalaris arundinacea), alkali I sacaton (Sporobolus airoides), foxtail barley (Hordeumjubatum), salt marsh bulrush (Scripus paludosus), cattail (Typha latifolia), spike rush (Eleocharis macrostchya), and sedges (Carex spp.). The wetlands delineation identified about 60-acres of jurisdictional wetlands within the OMW A (see Figure I). Jurisdictional wetlands are defined as wetlands regulated under the Clean Water Act by the Army Corp of Engineers. Wetlands must meet hydric vegetation, hydrology, and hydric soils criteria to be classified as a jurisdictional wetland. It is estimated that less than 0.5 acres of wetlands would be directly impacted during construction activities by the Preferred Alternative. The East and West backwaters are about 0.8-acres and 2.0-acres in size, respectively. These backwaters will be monitored to determine the amount of impact. Potential wetland mitigation for the Preferred Alternative includes development of replacement habitat or providing replacement water to the backwaters. Fish and Wildlife Resources The OMW A supports diverse populations of fish and wildlife. The OMW A provides excellent .breeding and wintering bird habitat, and good wintering habitat for mule deer. Species documented during field investigations include mule deer (Odocoileus hemionus), mourning dove