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_ly_ The applicant's alluvial valley floor (AVF) investigation extended two miles upstream and downstream from the Hawk's Nest permit area boundary. A description of the AVF investigation can be found on pages 2.06-1 through 2.06-2 of Volume I-C of the application. Deposits located upstream of the proposed permit boundary are not apart of the hydrologic system that could be affected, and therefore no AVF determination will be made at this tune. From the eastern permit boundary downstream to the town of Somerset, no continuous body of alluvium in excess of 10 acres has been identified. Therefore, the North Fork of the Gunnison through the proposed Hawk's Nest permit area to the westernmost extension of mapping in Exhibit 2.04.5-B is found not to be an alluvial valley floor. Downstream from the town of Somerset, the valley widens and the alluvial valley floor findings made previously by the Division for the Atlantic Richfield (ARCOj Mt. Gunnison Mine identify a much larger body of unconsolidated alluvial deposits. Areas within Section 13 and 14 have been identified as currently supporting agriculture. On the basis of information provided, the North Fork of the Gunnison and its associated alluviwn in Section 18, T13S, k90W and Sections 13 and 14, T13S, R91W have been found to meet the criteria of alluvial valley floors. Pursuant to RuleL.06.8, the Division is required to make specific written findings on the effect of mining upon any AVFs within the permit and adjacent area. The findings of the North Fork AVF are presented below. The AVF is not within the mine permit area, and will not be physically disturbed by the mining activities. No impacts to the AVF are anticipated. Pursuant to Rule 2.06.8(5)(a)(i), the Division finds that the proposed surface coal mining operations would not interrupt, discontinue, or preclude farming on the alluvial valley floor. The alluvial valley floor will not be undermined or mined throuyh by the proposed operations. All surface disturbances are located more than 2 miles upstream from the alluvial valley floor, and would not interrupt, discontinue, or preclude agricultural activities on the alluvial valley floor. [. Pursuant to Rule 2.06.8(5)(a)(ii), the Division finds that the proposed surface coal mining operations would not materially damage the quality and quantity 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. No flow records are available for the ephemeral gulches that drain the permit area, but their contribution is a very minor component of the mean annual flow of the North Fork. Surface flow supplied to the alluvial valley floor along the North Fork comes primarily from areas upstream of the permit area and this flow is regulated by Paonia Reservoir. Western Slope Carbon owns water rights totalling 1,190.8 acre feet per year which is more than Sufficient to replace the approximately 215 acre feet per year required for use at the mine.