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characterized by high peak discharges, short flow durations and high sediment loads. The <br /> Roadside North Portal portion of the permit area has been removed from the permit via TR-70. <br /> On the east side of the river,the Roadside Mine undermined two additional canyons: Rapid Creek <br /> and Cottonwood Creek. Both creeks are intermittent during most years, but do flow continuously <br /> during wet years. Flows in these creeks occur primarily in response to annual snowmelt and <br /> seasonal precipitation events. Intake structures are present in both Rapid Creek and Cottonwood <br /> Creek to divert water from those drainages into reservoirs for later release which, along with water <br /> from other storage structures, can artificially increase the duration of stream flows. Several small <br /> unnamed drainages (washes) on the east side of the river will also be impacted by mining, either <br /> through surface disturbance or through undermining. <br /> The only other major surface water body within the permit area is the federally owned Highline <br /> Canal. This canal carries river water down the west side of DeBeque Canyon of the Colorado <br /> River,with siphons under the channels of Coal and Jerry Creeks. The Highline Canal is primarily <br /> used for agricultural purposes in the Grand Valley. Upon approval of TR-70, the Highline Canal <br /> is no longer immediately adjacent to the permit area. <br /> Soils <br /> Permit Section 2.04.12: The limited surface disturbance area associated with the North and <br /> South Portals facilities areas are considered"Rock Outcrop" areas, as defined by the NRCS. No <br /> prime farmland exists in the areas associated mining activity disturbances. The operator states, <br /> "None of the existing areas of land disturbed by surface facilities is considered prime farmland <br /> since, historically none of the disturbed areas are used as cropland. (Permit Tab 9 p. 9-6) The <br /> Soil Survey of the area shows no map units with designations of Prime Farmland by the NRCS. <br /> Soils in the general area are commonly high in sodium and, occasionally, saline. Soil mapping <br /> units identified within and adjacent to surface disturbed areas are Torriorthents-Warm Rock <br /> Outcrop Complex, Wrayha-Veatch-Rabbitex Complex, Barx-Clapper Complex, Cameo, <br /> Fluvaquents, and Uffens Loam. These consist primarily of gravelly to stony loams, often <br /> calcareous, with slight to moderate alkalinity. All tend to have low available water capacity, due <br /> to the stony to cobbly textures. Occasional clay loams are found with high water capacity. The <br /> stoniness limits their successful utilization. Low organic matter content and elevated SAR values <br /> 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 <br /> topography. The depth of the soils range from 1 inch to greater than 60 inches,with the shallower <br /> soils of 0 to 40 inches along the side slopes of the canyons and the deeper soils located in the valley <br /> floors. The deeper soils tend toward the sandy loams while the shallower soils tend to be stony <br /> loams. <br /> Further information on soils can be found in Tab 9 of the permit application document. <br /> 10 <br />