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-28- The Somerset Mine has mine workings beneath Hubbard, Elk, and Bear Creeks. These streams are perenial, ephemeral and intermittent respectively, and drain directly to the North Fork. Bear Creek is perennial below the Somerset Mine's discharge point, where the stream flow is sustained by the mine discharge. Both the Blue Gibbon and the Somerset mines have surface facilities and underground workings within the Hubbard Creek Drainage Basin. During 198G, Hubbard Creek flows ranged from 3 cfs to 130 cfs with an average flow of 31 cfs. The estimated annual yield for Hubbard Creek was 24,700 acre-feet/year,"or 8% of the total flow of the North Fork for the year 1980, measured at Somerset, Colorado. Water quality data for Hubbard Creek are presented in Tables 4a and 4b. In a preliminary spring survey conducted at the Blue Ribbon Mine site, only one ephemeral spring was noted and mapped. This spring is located below the Blue Ribbon Mine bench. A survey of water rights records conducted by the State Water Resources Division for the Somerset Mine revealed that there are no adjudicated springs tributary to Hubbard Creek on or adjacent to the permit areas of the Blue Ribbon and Somerset mines. Three separate drainages are located within or adjacent to the Orchard Valley Mine. Terror Creek drains the eastern portion of the life-of-mine area, and East and West Roatcap Creek drain the western portion. Stevens Gulch is an ephemeral drainage between the Terror Creek and Roatcap Creek drainage basins which drains the permit area. Stevens Gulch has a drainage area of 6.0 square miles. Four other un-named ephemeral streams drain areas within the Orchard Valley life-of=mine area. These streams drain directly to the North Fork or the fire Mountain Canal. The entire Roatcap Creek system contains no alluvial deposits due to the steep topography and overall drainage gradient. One irrigation ditch, the Overland Ditch, follows the topographic contours between the upper Roatcap Creek Drainage Basin to the upper West Muddy Creek Drainage Basin. There are several springs and numerous ponds within the permit and hydrologically adjacent area of the Orchard .Valley Mine. It appears that, from the data submitted to date, most of these springs and ponds are intermittent and depend upon seasonal precipitation and long-term weather patterns. The source of~most of the springs appears to be related to landslide complexes, faults and fractures, areas of colluvium/alluvium where ground water has accumulated, or the discharge points at the basal contact of the Rollins sandstone and lenticular sandstones of the Mesa Verde Formation. The current Bear and Mt. Gunnison mining operations are adjacent to Sylvester Gulch and Lone Pine Gulch, which are ephemeral streams flowing directly to the North Fork. Characteristics of the drainages