2007-11-16_REVISION - C1981041 (6)

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Soils Soils in the general area are commonly high in sodium and, occasionally, saline. Soil mapping units identified within and adjacent to surface disturbed areas are Torriorthents-Warm Rock Outcrop Complex, Wrayha- Veatch-Rabbitex Complex, Barx-Clapper Complex, Cameo, Fluvaquents, and Uffens Loam. These consist primarily of gravelly to stony loams, often calcareous, with slight to moderate alkalinity. All tend to have low available water capacity, due to the stony to cobbly textures. Occasional clay loams are found with high water capacity. The stoniness limits their successful utilization. Low organic matter content and elevated SAR values also limit vegetative growth on soils in the area. Variability of the characteristics of the soils on the permit area is primarily due to slope and topography. The depth of the soils range from 1 inch to greater than 60 inches, with the shallower soils of 0 to 40 inches along the side slopes of the canyons and the deeper soils located in the valley floors. The deeper soils tend toward the sandy loams while the shallower soils tend to be stony loams. Further information on soils can be found in Tab 9 of the permit application document. Climatology The permit area receives less than nine inches of precipitation annually and is characterized by moderately cold winters and warm summers. Average temperatures range between 27 deg. F in the winter and 79 deg. F in the summer, with relatively even distribution of precipitation during the year. The average speed and direction of the prevailing winds in the permit area is 8.0 mph from the southwest. Vegetation The mesas and the valley slopes at the canyon base support sparse salt desert vegetation, including grasses such as galleta (Hilaria 1'a mesii), indian ricegrass (O!yzopsis hymenoides) and squirrel tail (Sitanion h_ystrix) and shrubs such as winterfat (Ceratoides Janata), shadscale (Atriplex confertifolia), big sagebrush (Artemisia tridentata) and fourwing saltbrush (A triplex canescens). The riparian zone adjacent to the Colorado River supports a variety of grasses, shrubs and trees, including willows Salix s.), cottonwoods (Populus spy), salt cedar (Tamarix parviflora), and bluegrass (Poa sp.). Further information on vegetation can be found in Tab 10 of the permit application. Wildlife Canyon walls in the permit area provide potential raptor nesting sites, and peregrine falcon nesting has been documented in the permit area in recent years. The river is used by waterfowl during migration, wintering and nesting seasons. Western portions of the permit area provide winter range for mule deer, and overlap a portion of a federally designated wild horse management area. During winter months, bald eagles have been observed along the Colorado River through DeBeque Canyon. Four species of threatened or endangered fish may potentially inhabit the Colorado River in this area. These are the bonytail, Colorado pikeminnow, razorback sucker, and humpback chub.. Permit Renewal No. 5 11 November 16, 2007