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On the east side of the river, the Roadside Mine will undermine two additional canyons: Rapid Creek and <br />Cottonwood Creek. Both creeks are intermittent during most years, but do flow continuously during wet years. <br />Flows in these creeks occur primarily in response to annual snowmelt and seasonal precipitation events. Intake <br />structures are present in both Rapid Creek and Cottonwood Creek to divert water from those drainages into <br />reservoirs for later release which, along with water from other storage structures, can artificially increase the <br />duration of stream flows. Several small unnamed drainages (washes) on the east side of the river will also be <br />impacted by mining, either through surface disturbance or through undermining <br />The only other major surface water body within the permit area is the federally owned Highline Canal. This <br />canal carries river water down the west side of DeBeque Canyon of the Colorado River, with siphons under the <br />channels of Coal and Jerry Creeks. The Highline Canal is primarily used for agricultural purposes in the Grand <br />Valley. <br />Soils <br />Soils in the general area are commonly high in sodium and, occasionally, saline. Soil mapping units identified <br />within and adjacent to surface disturbed areas are Torriorthents -Warm Rock Outcrop Complex, Wrayha- <br />Veatch- Rabbitex Complex, Barx- Clapper Complex, Cameo, Fluvaquents, and Uffens Loam. These consist <br />primarily of gravelly to stony loams, often calcareous, with slight to moderate alkalinity. All tend to have low <br />available water capacity, due to the stony to cobbly textures. Occasional clay loams are found with high water <br />capacity. The stoniness limits their successful utilization. Low organic matter content and elevated SAR <br />values also limit vegetative growth on soils in the area. <br />Variability of the characteristics of the soils on the permit area is primarily due to slope and topography. The <br />depth of the soils range from 1 inch to greater than 60 inches, with the shallower soils of 0 to 40 inches along <br />the side slopes of the canyons and the deeper soils located in the valley floors. The deeper soils tend toward <br />the sandy loams while the shallower soils tend to be stony loams. <br />Further information on soils can be found in Tab 9 of the permit application document. <br />Climatology <br />The permit area receives less than nine inches of precipitation annually and is characterized by moderately cold <br />winters and warm summers. Average temperatures range between 27 deg. F in the winter and 79 deg. F in the <br />summer, with relatively even distribution of precipitation during the year. <br />The average speed and direction of the prevailing winds in the permit area is 8.0 mph from the southwest. <br />Vegetation <br />The mesas and the valley slopes at the canyon base support sparse salt desert vegetation, including grasses such <br />as galleta (Hilaria jamesii), indian ricegrass (Orvzopsis hymenoides) and squirrel tail (Sitanion hystrix) and <br />shrubs such as winterfat (Ceratoides lanata), shadscale (Atriplex confertifolia), big sagebrush (Artemisia <br />tridentata) and fourwing saltbrush (Atriplex canescens). The riparian zone adjacent to the Colorado River <br />supports a variety of grasses, shrubs and trees, including willows (Salix spp.), cottonwoods (Populus spp.), salt <br />cedar (Tamarix parviflora), and bluegrass (Poa spp.). <br />Further information on vegetation can be found in Tab 10 of the permit application. <br />Permit Revision No. 5 9 July 10, 2012 <br />