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WATER REPLACEMENT PLAN SPECIFIC DESCRIPTION • WEST ROATCAP DRAINAGE BASIN TOPOGRAPHY East and West Roatcap Creeks meet in Section 26, T.135, R.92W. They meet at elevation 6,.600 feet above sea level. The West Roatcap drainage pattern exten's approximately 22,000 feet in a generally northwest direction. The average gradient is approximately 12%, with the steepest sections of the drain- age pattern in the intermediate elevations. The West Roatcap drainage area is intercepted in the north by the Overland Ditch. The total area of the West Roatcap Drainage Basin is approximately 8.2 square miles. Approximately 7.4 square miles is outside of any existing lease or proposed lease. That is approximately 89.8X of the total drainage area. Like all of the creeks in the area, West Roatcap occupies steep walled, gently sinuous, to nearly straight canyons. ALLUVIAL/COLLUVIAL DEPOSITS The streambeds contain basaltic boulders of 4-I8" in dimension with winor local deposits of sand and gravel. These sediments are considered dominantly collu- vium deposited in degrading streams with subsequent reworking and size dimen- sion of a minor amount to alluvium status. There are no flood plains or ter- races which are distinctive of alluvial valleys which could provide areas large enough to be sufficient for crop production by irrigation or subirrigation. • Long Draw is a tributary to West Roatcap Creek and is located in Section 16. It is an upland swale bordered by Mesa Verde outcrops with some rubble on the north slopes and typical landslide topography of basaltic rubble on the south slopes. The swale is approximately 60 acres in extent; 500-700 fee[ wide, and has a length of approximately 5,000 feet. The slope of the surface on either side introvert to the stream channel is approximately 20Y.. Further information on alluvial/colluvial deposits may be found in Section 2.04.7 of the Orchard Valley Mine Mining and Reclamation Permit Application. SOIL TYPF. For detailed information on the soil types mapped within the area, please see the Paonia Area Soil Survey, January 1981, U. S. Department of Agriculture, Soil Conservation Service. The soil within the Long Draw has been mapped as Delson Loam on 3-12% slopes and Delson Stony Loam on 3-20Y. slopes. There are some well rounded gravels of 1/2 to 1" in dimension in the stream channels. There is no indication that the deep soils of the Delson Loam were stream laid. There are no flood plains, or terraces indicative of alluvial deposits, and where the stream has exposed fresh cuts of 8 feet in height, no stratafied sediments were observed. The drainage basin is dominated by Delson Loam to Delson Very Stony Loam. •