Laserfiche WebLink
<br /> <br /> <br /> 66 C1981-041 RN7 findings <br />at the UTL. Of the total, 13.9 acres are located inside the loop and 12.2 acres are <br />outside the loop. Therefore, it would be possible for the Operator to restore the <br />capability of flood irrigation to 12.2 acres, 87% of the acreage for which irrigation <br />water is available. <br /> <br />Only minor disturbance has occurred outside the UTL loop. Reclamation and <br />restoration of the essential hydrologic functions outside of the UTL loop area <br />involved minimal regrading to reestablish the original topography, replacing <br />topsoil, and revegetating. Although the 12.2 acres outside the loop that were <br />previously irrigated are now heavily overgrown with brush and cottonwood trees, <br />the industrial use will not prohibit the capability to restore flood irrigation to these <br />12.2 acres. <br /> <br />In summary, surface coal mining and reclamation operations will be conducted to <br />preserve, throughout the mining and reclamation process, the essential hydrologic <br />functions of the alluvial valley floors not within the permit area, and operations <br />will be conducted to reestablish the essential hydrologic functions of alluvial <br />valley floors within the permit area (4.24.2(1). The permittee will be required to <br />restore the essential hydrologic functions on the entire alluvial valley floor where <br />disturbance has occurred, with exception of the area located inside the UTL loop <br />as a result of the post-mine land use change from wildlife habitat to <br />industrial/commercial with PR-4. As described above, the post-mine land use <br />change precludes the Operator’s capability to restore flood irrigation to a small <br />amount (1.8 acres) of the original 14 acres for which water is available. <br />Subirrigation throughout the UTL area is not affected by the post-mine land use <br />change associated with PR-4 and no actions were necessary to reestablish <br />subirrigation. <br /> <br />Rapid/Cottonwood Creek Area <br /> <br />Four distinct areas were examined for identification of alluvial valley floors in the <br />vicinity of Rapid Creek and Cottonwood Creek. These areas were Cottonwood <br />Creek, Rapid Creek, minor ephemeral streams and the Colorado River adjacent to <br />the Rapid Creek and Cottonwood Creeks watersheds. None of these areas are <br />covered by the "grandfathering" exemption. <br /> <br />The Cottonwood Creek valley does not meet the geomorphic characteristics of an <br />alluvial valley floor. The valley is narrow, and any fill material does not meet the <br />AVF size criteria. <br /> <br />Valley fill deposits located along Rapid Creek have been interpreted as a mudflow <br />fan deposit which has been modified and reworked by Rapid Creek to form three <br />terrace levels. The upper terraces (T2 and T3) are irrigated or have been irrigated <br />with the flow from Rapid Creek. The lowest terrace (T1) is narrow and has not <br />been flood irrigated. The T1 terrace includes a narrow band of subirrigation along <br />the creek, but the species present are not agriculturally useful. Subirrigated