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-2t- in. and only 2.19 in, of this total is in the form of snow. The disturbed areas of the mine sites are between 7,000 and 7,500 ft. in elevation and are located between the Trinidad and North Lake stations. The mean annual precipitation at the New Elk Mine is calculated to be 16.9 in. with snowfa]1 contributing 5.00 in, to this total. Although runoff is dominated by snowmelt, the peak discharges occur in response to intense rainfall during the summer. At the Stonewall gaging station during water year 1979, the average discharge was 18.1 cfs with flow ranging from 2.8 cfs to 172 cfs. The minimum average weekly flow at Stonewall was approximately 4 cfs. During water year 1979, flows ranged from 7.6 cfs to 6,620 cfs at the Madrid station. The minimum weekly average flow during the water year reported in the permit application was about 7 cfs at the Madrid station. At the Madrid gaging station, the average flow for the 9 year period of record is 45.7 cfs, and the average annual yield is 33,100 acre-feet. Over the period of record, flow ranged from a low flow of 3.0 cfs to a high flow of 14,300 cfs. Water quality data on the Middle Fork of the Purgatoire at Stonewall and the Purgatoire at Madrid are available from the USGS. Data above and below both the New Elk and Golden Eagle mines have been included in the permit application. The water in the Purgatoire and the Middle Fork of the Purgatoire is a calcium-bicarbonate type water. Total dissolved solids concentrations in the mine area normally run below 300 mg/1 throughout the year. Monitoring below the New Elk Mine shows some increase in sodium reflecting the effects of past mining activities. This effect is diluted by flow from the North Fork of the Purgatoire River which joins the Purgatoire River between the New Elk and Golden Eagle mines. The applicant's analyses of impacts of mining on the Purgatoire River use data from water year 1979 and can be found in the original New Elk and Golden Eagle permit applications. E. water Use Ground water used in the area comes primarily from shallow alluvial sources. This water is used primarily for domestic, livestock and irrigation purposes. Alluvial ground water is also used for municipal water downstream from the mines. A few deeper wells in the vicinity of the New Elk Mine may tap bedrock ground water sources. Two of these wells are used for the mining operation at the New Elk Mine. Water from these bedrock wells is used for domestic and industrial purposes. Surface water within the Purgatoire River basin is used primarily for irrigation of strath and alluvial terraces. The width of the valley ranges from a few hundred to a few thousand feet. Where the geometry of the valley permits, limited flood irrigation is practiced. It is estimated that 6,000 acre-feet are diverted from the Purgatoire for irrigation above the Madrid station. Irrigated lands are, for the most part, located on the strath terraces. Irrigation on the lower alluvial terraces is also practiced, but the small size often precludes viable irrigated agricu]ture. Much more -~+~~~:.,e ;.-~;~ar;nn nrri~rc in the vallev downstream of Trinidad.