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12 Most .springs are noted to come from lenticular sands, and the recharge and discharge areas of these springs are concluded to be in close proximity because of the highly seasonal variations in flow. However, it is Likely that some of the more prominent and perennial springs receive their recharge, at least in part, from greater distances and from more continuous aquifer systems which have greater storage capacities--perhaps extending into the Minnesota Creek drainage. ~~ Only one production well exists within the permit area and is located at the Bear Mine. This alluvial well,is used only as a backup source of water when the water rights for the springs in Sylvester Gulch are called by senior water rights holders. A number:Of the springs have been adjudicated, apparently for irrigation and minekusage downstream. Water rights associated with those springs are discussed with the review of~surface water rights. Nine monitor wells were sampled,onfi"the mine plan area. Total dissolved solids (TDS) in all wells sampled ranged from 252 mg/1 to over 6,000 mg/1. In the Barren Member, TDS ranges from 252 mg/1 to 2,215 mg/l, with high seasonal variations. In the F-seam, TDS ranges from 900 to 1,700 mg/I, with much less notable seasonal variations.. Total dissolved solids concentrations observed in the spring sampling ranged up to 2,100 mgfl; however, averages were 400-600 mg/1 for most springs,.., Water quality data from the springs are presented on Table 2.8..7.R. Numerous parameters,in the natural ground water exceed recommended limits set for drinking water by the Colorado Department of Health. Those in excess include+ iron, ammonia, boron, zinc, 1ead,~~ manganese, copper, fluoride, alkalinity, and sulphates. The Mt. Gunnison Mine No. 1 permit area consists of 19,341 acres located approximately 5 miles east of Paonia, Colorado. 4'he mine area lies within the drainage of the North Fork of the Gunnison River which is tributary to the Colorado River system. The area is mountainous with elevations ranging between 6,000 feet at Somerset and~12, 719 feet at Mt. Gunnison. The climate of the region is typical of the Rocky Mountain area. The valley in whcch Paonia and Somerset are situated is semi-arid with annual precipitation averaging about 15 inches per year. Mean annual precipitation increases with elevation, reaching approximately 40 inches per year on the summit of Mt. Gunnison. The May-September precipitation is 5 inches for the lowlands~ar~d 13 inches for the mountain peaks. This indicates that snowfall patterns play an important part in ~8etermining the hydrology of the area. Temperature extremes at Paonia have ranged~ftom -28 Fin January to 100 F during July and August. The avera~•e annual temperature is approximately 49 F. Snowfall averages 58 inches per year. The North Fork of the Gunnison River is the major drainage for the mine site. Streams on the northern portion of the permit area drain directly into the North Fork near Somerset. Minnesota Creek drains the remaining areas within thec permit boundaries. It enters the North Fork near Paonia. .ate, fi.. The North Fark has an annual streamflow at Somerset of approximately 313,500 acre feet per year (1962-1979). Th2 flow is regulated by the Paonia Reservoir 5 miles upstream, which became operational in 1962. Flows during that period have ranged from a high of 451,300 acre-feet per year in water year 1962 to a Zow of 82,270 acre-feet in water year 1977.