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• protection as listed species. <br /> H. Cultural Resources <br /> The area was not inventoried for cultural resources because no disturbance is proposed, the <br /> elevation of the area, the steep slopes and vegetative cover. <br /> I. Water Resources <br /> Surface Water <br /> The entire permit area is within the North Fork of the Gunnison River (North Fork) drainage, which <br /> is part of the Colorado River system. The North Fork watershed, above the lease area, is <br /> approximately 531 square miles, having a mean basin elevation of 8,900 feet. About two thirds of <br /> the watershed is forest land and one third rangeland. The flow of the North Fork varies seasonally <br /> (Figure 11. with high flows occurring during spring from snowmen. After snowmen, flows begin to <br /> recede, reaching their low during winter. The 100-year flood event produces a flow rate of about <br /> 7,920 cubic feet per second (Figure 2). <br /> East Roatcap Creek, an intermittent creek, drains in a southerly direction from the proposed lease <br /> area into the North Fork. It is dry by late summer because discharge from the alluvium is limited. <br /> The drainage area of East Roatcap Creek is about 4 miles square and the headwaters is located on <br /> the proposed lease tract. Flow results from spring snowmelt and high intensity rainfall events, <br /> which commonly occur in late summer and water from Overland Ditch. It has been postulated that <br /> the drainage pattern coincides with joint systems in the underlying rock. These joint systems <br /> possibly provide hydraulic connection between surface and subsurface flow systems associated <br /> • with the Mesaverde Formation. <br /> Water quality data (inorganic constituents and suspended sediment concentrations) for the North <br /> Fork indicates that generally, water quality is good. The water is an alkaline, soft, calcium- <br /> bicarbonate-sulfate type with total dissolved solids concentration averaging around 100 mgA. The <br /> water is cold, with winter temperatures near freezing and summer temperatures in the 18-20 <br /> degree C range. Suspended solids concentration averages near 50 mgA with maximum <br /> concentrations occurring during snowmelt, in the range of 200-250 mgA. Both dissolved metals <br /> and nutrient concentrations are generally low throughout the year. <br /> Ground Water <br /> The Mesaverde Formation is the primary hydrogeologic unit within the proposed lease area. <br /> Ground water may be transmitted down dip and northward within the Measverde Formation and <br /> discharge somewhere north of the Grand Mesa, or it may discharge somewhere down the North <br /> Fork Gunnison River valley. Any discharge would be small and likely subject to evapotranspiration. <br /> Essentially all ground water in the Mesaverde Formation is associated with secondary porosity <br /> (fracturing or natural bedding planes), which usually occurs in a non-continuous fashion. Possible <br /> hydraulic connection to surface water also occurs along joint systems in the Mesaverde Formation <br /> that coincide with the overlying ephemeral gulches. Recharge to the Mesaverde Formation from <br /> these joints would be mainly during the snowmelt season. Generally, water yields of the <br /> Mesaverde Formation are less than 10 gpm. In areas where secondary porosity is high, water <br /> yields can be much greater. Water quality in the Mesaverde Formation is an alkaline sodium- <br /> bicarbonate type, with Total Dissolved Solids concentration ranging from several hundred to several <br /> . thousand mgA. <br /> Unconsolidated quaternary deposits can transmit a significant quantity of water. The more <br /> extensive the unconsolidated deposit, the more potential there is for ground-water recharge, <br /> Page 8 <br />