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protection as listed species. H. Cultural Resources The area was not inventoried for cultural resources because no disturbance is proposed, the elevation of the area, the steep slopes and vegetative cover. Water Resources ~yrface Water The entire permit area is within the North Fork of the Gunnison River (North Fork) drainage, which is part of the Colorado River system. The North Fork watershed, above the lease area, is approximately 531 square miles, having a mean basin elevation of 8,900 feet. About two thirds of the watershed is forest land and one third rangeland. The flow of the North Fork varies seasonally (Figure 11, with high flows occurring during spring from snowmelt. After snowmelt, flaws begin to recede, reaching their low during winter. The 100-year flood event produces a flow rate of about 7,920 cubic feet per second (Figure 21. East Roatcap Creek, an intermittent creek, drains in a southerly direction from the proposed lease area into the North Fork. It is dry by late summer because discharge from the alluvium is limited. The drainage area of East Roatcap Creek is about 4 miles square and the headwaters is located on the proposed lease tract. Flow results from spring snowmelt and high intensity rainfall events, which commonly occur in late summer and water from Overland Ditch. It has been postulated that the drainage pattern coincides with joint systems in the underlying rock. These joint systems possibly provide hydraulic connection between surface and subsurface flow systems associated with the Mesa Verde formation. Water quality data (inorganic constituents and suspended sediment concentrations) for the North Fork indicates that generally, water quality is good. The water is an alkaline, soft, calcium- bicarbonate-sulfate type with total dissolved solids concentration averaging around 100 mgA. The water is cold, with winter temperatures near freezing and summer temperatures in the 18-20 degree C range. Suspended solids concentration averages near 50 mgA with maximum concentrations occurring during snowmelt, in the range of 200-250 mgA. Both dissolved metals and nutrient concentrations are generally low throughout the year. Ground Water The Mesaverde Formation is the primary hydrogeologic unit within the proposed lease area. Ground water may be transmitted down dip and northward within the Measverde Formation and discharge somewhere north of the Grand Mesa, or it may discharge somewhere down the North Fork Gunnison River valley. Any discharge would be small and likely subject to evapotranspiration. Essentially all ground water in the Mesaverde Formation is associated with secondary porosity (fracturing or natural bedding planes), which usually occurs in anon-continuous fashion. Possible hydraulic connection to surface water also occurs along joint systems in the Mesaverde Formation that coincide with the overlying ephemeral gulches. Recharge to the Mesaverde Formation from these joints would be mainly during the snowmelt season. Generally, water yields of the Mesaverde Formation are less than 10 gpm. In areas where secondary porosity is high, water yields can be much greater. Water quality in the Mesaverde Formation is an alkaline sodium- bicarbonate type, with Total Dissolved Solids concentration ranging from several hundred to several thousand mgA. Unconsolidated quaternary deposits can transmit a significant quantity of water. The more Paqe 8