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f': (~ during the winter of 1976-77, water year 1!377 was a dry year. Using the data from Junes 1977 - April 1978 as an indication of 1977 water year conditions, vre have plotted high, low and estimated mean annual . runoff in cornpari<.;on with drainage area on Figure 1. Only the drainage area above the gaging station is plotted in Figure 1. From Figure 1 it is apparent that the percentage of water contribution by basin cannot bey determined solely on the basis of basin areas. On a unit area basis, water yields from South Prang and Horse Creek <rre much higher than water yields from either Lick Creek or Dry Fork. Percentage contrit~ution by basin are best approximat~:d from the mEaan annual runoff estimates given previously. Once the Lower East Fork gaging station is installed, we will be able to better quantify the percentage water <:ontribution by basin for i4innesota Creek above t:he 1linnesota and Turner Ditch diversions. The degree of accuracy achievable will depend upon our ability to assess the effects of lone Cabin Ditch and Beaver Dam Ditch on the flow recorded at the East Fork gaging station. South Prong and Horse Creek have higher yields than either Dry Fork or Lick Creek. Flow variation for Dry Fork is affected by storage and release from i4inne~sota Reservoir. Also, Dry Fork flows include Detep Creek Ditch which is not included in the drainage area of Dry Fork. The other surface water bodies associated with the Mt. Gunnison I•t•ine permit area are I~linnesota and Beaver Reservoirs. Both reservoirs are located below the outcrop of the F seam coal and consequently will not be directly affected by mining. Springs located on the mine permit area play a minor role in main- taining low flows. In fact, most springs dry up early during the summer and streamer originating on the permit area are ephemeral. This indicates that groundwater supplying springs is of limited extent. Also, the discharge rates of the springs respond closely to preci;rita- tion events indicz~ting that the recharge areas for the springs are ~4)