2022-11-07_REVISION - C1981041 (2)

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aerial photos taken on Octoberl4, 1976 there were a total of 26.1 irrigated acres at the UTL. Of the total, 13.9 acres are located inside the loop and 12.2 acres are outside the loop. Therefore, it would be possible for the Operator to restore the capability of flood irrigation to 12.2 acres, 87%of the acreage for which irrigation water is available. Only minor disturbance has occurred outside the UTL loop. Reclamation and restoration of the essential hydrologic functions outside of the UTL loop area involved minimal regrading to reestablish the original topography, replacing topsoil, and revegetating. Although the 12.2 acres outside the loop that were previously irrigated are now heavily overgrown with brush and cottonwood trees, the industrial use will not prohibit the capability to restore flood irrigation to these 12.2 acres. In summary, surface coal mining and reclamation operations will be conducted to preserve,throughout the mining and reclamation process,the essential hydrologic functions of the alluvial valley floors not within the permit area, and operations will be conducted to reestablish the essential hydrologic functions of alluvial valley floors within the permit area (4.24.2(1). The permittee will be required to restore the essential hydrologic functions on the entire alluvial valley floor where disturbance has occurred, with exception of the area located inside the UTL loop as a result of the post-mine land use change from wildlife habitat to industrial/commercial with PR-4. As described above, the post-mine land use change precludes the Operator's capability to restore flood irrigation to a small amount (1.8 acres) of the original 14 acres for which water is available. Subirrigation throughout the UTL area is not affected by the post-mine land use change associated with PR-4 and no actions were necessary to reestablish subirrigation. Rapid/Cottonwood Creek Area Four distinct areas were examined for identification of alluvial valley floors in the vicinity of Rapid Creek and Cottonwood Creek. These areas were Cottonwood Creek,Rapid Creek,minor ephemeral streams and the Colorado River adjacent to the Rapid Creek and Cottonwood Creeks watersheds. None of these areas are covered by the "grandfathering" exemption. The Cottonwood Creek valley does not meet the geomorphic characteristics of an alluvial valley floor. The valley is narrow, and any fill material does not meet the AVF size criteria. Valley fill deposits located along Rapid Creek have been interpreted as a mudflow fan deposit which has been modified and reworked by Rapid Creek to form three terrace levels. The upper terraces (T2 and T3) are irrigated or have been irrigated with the flow from Rapid Creek. The lowest terrace (T1) is narrow and has not 64