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West Elk Mine . would favor clay deposits in this reach of Sylvester Gulch suggests that the valley deposits are of glacial or perhaps colluvial (mass movement) origin. The flood irrigation potential of the site is also questionable. Stream flow records near the mouth of Sylvester Gulch indicate that flow during the critical months of July and August are not common. Agricultural development would be limited to grasses and pasture because of the elevation and short growing season. Outside the permit azea, but within the reconnaissance investigation area, there aze two general areas of alluvial deposits. One is along the North Fork of the Gunnison River, and the other is along Minnesota Creek and the East Fork of Minnesota Creek. The alluvial valley deposits aze wider and contiguous where the streams leave the narrow canyons. Agricultural development is evident on these lower valley fills. Isolated hay meadows are also found further up in the narrow valley of the East Fork of Minnesota Creek. However, as one moves up the East Fork, these areas become more isolated and were not found above the 6,800 ft. elevation. Map 66 delineates those azeas along the main stem of Minnesota Creek where agricultural activities are supported by irrigation or flood irrigation. For the purposes of this evaluation, mapping was stopped at the west section line of Section 2, T14S, R91 W, a point over two miles from the pemut boundary and downstream of the headgates of the Turner Ditch and Minnesota Ditch. During low flows (i.e., irrigation demand periods) these two ditches effectively dry up Minnesota Creek. Below this point return flow utilization, if any, is the water source for activities during low flows. • hi the azea where irrigation is used, the flow regime of Minnesota Creek is totally controlled by a series of reservoirs and diversion ditches. Beaver Reservoir effectively regulates spring runoff on the East Fork as it is being filled. Reservoir releases regulate stream flow during late summer. Minnesota (Monument) Reservoir effectively regulates spring runoff from Dry Fork with reservoir releases controlling late summer flows. Additionally, the Deep Creek Ditch, an interbasin diversion, supplies water to Minnesota Reservoir to satisfy the Reservoir Company's refill right. According to the officers of the various ditch and reservoir companies, the southern tributaries to Minnesota Creek (South Fork, Lake Fork, and Sam's Creek) aze all subjected to diversion and contribute very little water during spring runoff and no water in the irrigation season. All water available at the Beaver Reservoir will not be diminished as a result of mining. Map 27 shows that the F Seam outcrops at the point where East Fork crosses the pemut azea. No mining will take place under the East Fork. As a result, the West Elk Mine will not affect the East Fork drainage. Because most or all of the water from the southern tributaries to Minnesota Creek is diverted by the various ditches, Minnesota and Beaver Reservoirs regulate a majority of the spring runoff in Minnesota Creek. During periods of low flow the reservoir releases into East Fork and Dry Fork comprise the total flow of Minnesota Creek. By not affecting the integrity of the reservoirs and their water supplies, Mountain Coa] Company will be insuring that mining activities associated with the West Elk Mine will have no impact on the alluvial valley floor areas along the main stem and East Fork of Minnesota Creek. • During the site visit on September 9, 1980, the valley azeas of Dry Fork above Minnesota Reservoir and East fork above the South Fork/East Fork confluence and below Beaver Reservoir were 2.06-5