2011-01-13_REVISION - C1980006 (9)

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IX. Protection of Fish, Wildlife, and Related Environmental Values - Rule 4.18 A. The applicant has proposed the use of persistent pesticides on the site during reclamation operations only if necessary. Kerr Coal Company has consulted, and will continue to consult as appropriate, with the Colorado State University Extension Service to determine control measures. Prior to implementation of any control measure, Kerr Coal Company will consult with the Division (Rule 4.18(4)(g)). X. Operations on Alluvial Valley Floors - Rules 2.06.8 and 4.24 Identification of Alluvial Valle,, Floors The applicant has identified five areas within or adjacent to the mine plan area, and one area within or adjacent to the loadout, which meet the geomorphic criteria of alluvial valley floors. Deposits of unconsolidated alluvial materials were identified along the Illinois River, the Canadian River, Bolton Draw, Bush Draw, Williams Draw, and Sudduth Draw (Maps 5a and 15a). In two of these areas, Bush Draw and Williams Draw, there apparently is not sufficient water to support agricultural activities. There is no existing or historic flood irrigation in these valleys (page 785-16aa), these valleys are not capable of flood irrigation (Exhibit 37a), and the areas where the vegetation suggests sub-irrigation are discontinuous and limited to narrow bands along the channel ways (Map 15a). Therefore, Bush Draw and Williams Draw are not alluvial valley floors. The four remaining areas meet the criteria for alluvial valley floors. The floodplain of the Illinois River meets the water availability criteria for sub-irrigation (page 785-27). The floodplain of the Canadian River is currently flood irrigated (page 785-27), and is also sub- irrigated (page 785-24). Bolton Draw contains 55 acres of a flood-irrigated pasture. The water used for this irrigation is derived from the Michigan River (page 785-aa). In addition, 95 acres of Bolton Draw alluvium contain vegetation suggesting sub-irrigation (Map 15a). At one site, soil moisture data (Exhibit 38) collected during the week of September 15, 1980, show the capillary fringe associated with the alluvial water table to be within 1.5 feet of the surface. However, data are not available for more than one site, or through the growing season. Therefore, based upon the available data, the entire 95 acres are assumed to be sub-irrigated. Analysis of the regional flood irrigation practices (Exhibit 37a) indicates no capacity for additional flood irrigation using runoff from the watershed itself. The applicant has identified 77 acres of alluvium along Sudduth Draw, which have vegetation suggestive of sub-irrigation. Soil moisture data (Exhibit 38) collected during the week of September 13, 1980, indicates sub-irrigation. At the location sampled, the root zone extended 25