2008-03-03_PERMIT FILE - C2006085 (2)

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direction for a distance of a little over 3 miles from its headwaters to its junction with the Arkansas River. Fawn Hollow exhibits characteristics typical of an transitional to lowland drainage with moderate flow gradients, and a wide, flat channel with limited vegetation in the upper drainage area. The drainage narrows and the gradient increases slightly as the creek flows through the cliff-forming sandstone k~eds of the Raton Formation where the drainage leaves the permit area. The channel base consists primarily of small to medium sized unconsolidated colluvial outwash materials within the permit area. Before entering the Arkansas River, Fawn Hollow drainage flows for approxirately one-half mile across that river's alluvial flood plain deposits through areas historically used for agriculture. The only other drainage within the proposed permit area is an ephemeral creek locally called 'Spring Creek', which flows across a short distance of the northwest portion of the area. The headwaters of the drainag~° lie at approximately 6,100 feet, at a location approximately 2 miles west of the southwest corner of the permit area. Spring Creek's drainage basin encompasses approximately 2 square miles, all of which is within the synclinal basin previously described. The creek runs off the permit onto areas used primarily for agricultural and residential purposes and joins Pump Ditch, near the Arkansas .~ River, at a distance of approximately 1 mile. Spring Creek drainage is a relatively small ephemeral drainage adjacent to and parallel to Fawn Hollow, and exhibits very similar characteristics to the Fawn Hollow drainage previously discussed. All of the streams discussed in this section are tributary to the Arkansas River. The Arkansas is the major perennial drainage in this region, with contributing drainage area of approximately 4,000 square miles upstrE~am of Portland, which is just east of Florence. Most of the river drainage area is heavily forested, mountainous terrain east of the Continental Divide. Flows in the Arkansas River are heavily influenced by spring runoff since there are no reservoirs constructed upstream from this area. With drainage derived primarily from forested mountain terrain, suspended solids levels in the Arkansas River are relatively low over much of the year except following major storm events. Dissolved solids and specific chemical constituents are elevated as a result of drainage near the headwater areas from major mining areas where extensive underground mining of metals occurred near its headwaters during the rnid to late 1800's and early 1900's. • 2.04-26 Revised 11/05/07