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the Colorado State University Extension Service to determine control measures. <br />Prior to implementation of any control measure Kerr will consult with the <br />Division. (4.18(4)(8)). <br />VIII. Operations on Alluvial Valley Floors Rules 2.06.8, 4.24 <br />Identification of Alluvial Valley Floors <br />The applicant has identified five areas within or adjacent to the mine plan area, and one area <br />within or adjacent to the loadout, which meet the geomorphic criteria of alluvial valley floors. <br />Deposits of unconsolidated alluvial materials were identified along the Illinois River, the <br />Canadian River, Bolton Draw, Bush Draw, Williams Draw, and Sudduth Draw <br />(Maps Sa and 15a). <br />In two of these areas (Bush Draw and Williams Draw), there apparently is not sufficient water <br />to support agricultural activities. There is no existing or historic flood irrigation in these <br />valleys (p. 785-16aa), these valleys are not capable of flood irrigation (Exhibit 37a), and the <br />areas where the vegetation suggests sub-irrigation are discontinuous and limited to narrow <br />bands along the channel ways (Map 15a). Therefore, Bush Draw and Williams Draw are not <br />alluvial valley floors. <br />The four remaining areas meet the criteria for alluvial valley floors. The floodplain of the <br />Illinois River meets the water availability criteria for sub-irrigation (p 785-27). The floodplain <br />of the Canadian River is currently flood irrigated (p 785-27), and is also sub-irrigated (p. <br />785-24). <br />Bolton Draw contains 55 acres of a flood irrigated pasture. The water used for this irrigation <br />is derived from the Michigan River (p. 785-aa). In addition, 95 acres of Bolton Draw alluvium <br />contain vegetation suggesting sub-irrigation (Map 15a). At one site, soil moisture data <br />(Exhibit 38) collected during the week of September 15, 1980, show the capillary fringe <br />associated with the alluvial water table to be within 1.5 feet of the surface. However, data are <br />not available for more than one site, or through the growing season. Therefore, based upon <br />the available data the entire 95 acres are assumed to be sub-irrigated. Analysis of the regional <br />flood irrigation practices (Exhibit 37a) indicates no capability for additional flood irrigation <br />using runoff from the watershed itself. <br />The applicant has identified 77 acres of alluvium along Sudduth Draw which have vegetation <br />suggestive of sub-irrigation. Soil moisture data (Exhibit 38) collected during the week of <br />September 13, 1980, indicates sub-irrigation. At the location sampled, the root zone extended <br />approximately five feet into the capillary fringe. No existing or historic flood irrigation has <br />been <br />Marr Strip Mine, C-80-006 25 December 9, 1992 <br />