GENERAL41305 - Laserfiche WebLink

Home Browse Search

-13- is found not to be an alluvial valley floor based on its current size. The Colorado Department of Highways has relocated State Highway 133 to bisect the site under consideration. As a result, the area is now too small a unit to be practically farmed and, therefore, is excluded from further consideration. Zfiis area which is separated from the North Fork of the Gunnison River by Colorado Highway 133 is where the bulk of the lower waste pile construction activities will occur. Between Sylvester Gulch and the town of Somerset, several smaller bodies of alluvium lie along the course of the river. Two of these areas are occupied by the Hear Mine Portal and Bear loadout. None of these areas meet the size criteria of the State (10 acces), and these areas are found not be alluvial valley floors. Downstream from the town of Somerset, the valley opens up and the applicant has identified a much larger body of alluvium. Areas within Sections 13 and 14 have been identified as currently supporting agriculture. No specific information has been provided concerning flood irrigation (existing or potential) or subirrigation. On the basis of the information provided, the North Fork of the Gunnison and its associated alluvium in Section 18 (T135, R90W), and Sections 13 and 14 (T13S, R90W) are found to meet the criteria of alluvial valley floors. The alluvial valley floor probably continues downstream, but for those areas no determination is needed at this time due to limited impacts predicted. Alluvial Valley floors - Findings 1. The surface coal mining operations would not interrupt, discontinue, or preclude farming on an alluvial valley floor (Rule 2.06.8(5)). Although underground mining would occur in areas adjacent to the alluvial valley floor, all surface disturbances are located more than a mile upstream from the alluvial valley floor. The alluvial valley floor would not be undermined by the operations, nor will they be significantly affected by surface and ground water impacts from the surface operations. 2. The surface coal mining operations would not materially damage the quantity and quality of water in surface and underground water systems that supply those alluvial valley floors or portions of alluvial valley floors. All of the surface flow from the permit area drains to the North Fork of the Gunnison. 'Ihe applicant has monitored the largest two drainages crossing the permit area. During this period, Lone Pine Gulch has experienced no flow. Sylvester Gulch has experienced ephemeral stream flow. The record yield of 208 acre -ft/yr, in 1978 is less than 18 of the mean annual flow in the North Fork of the Gunnison River. Surface flow supplied to the alluvial valley floor along the North Fork comes primarily from areas upstream from the permit area and this flow is regulated by Paonia Reservoir which is located approximately 6 miles