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The valley associated with Pyeatt Gulch contains unconsolidated streamlaid deposits. All of these alluvial materials are located downstream of the proposed permit area and will, therefore, not be physically disturbed by mining. Land use along Pyeatt Gulch consists of cropland and undeveloped rangeland (see Map 35-B). Unirrigated wheat and native grass hay are grown along Pyeatt Gulch and constitute 719 acres of cropland. The average annual water yield for Pyeatt Gulch is 154 acre-feet. The applicant, through interviews with local Soil Conservation Service officials, has determined that this is an insufficient amount of water to economically practice flood irrigation. Flood irrigation is occasionally practiced in the Pyeatt Gulch valley. The McNamera Oitch (see Map M31) is fed water from a deep bedrock well. The ditch irrigates about 150 acres of crested wheat grass. Crop yields range from one to one-third tons/acre. The well is completed in bedrock to a depth of in excess of 400 feet. Since the ditch is not fed by surface water or alluvial ground water, Pyeatt Gulch does not constitute an AVF based upon the existing flood irrigation. Data supplied by the applicant indicate that the depth to the alluvial water table is from 5.6 feet to 7.7 feet. This water table is too deep for wheat and native grasses to be subirrigated. Therefore, based on the lack of sufficient water available in the drainage for agricultural benefit, Pyeatt Gulch is determined not to be an alluvial valley floor. The applicant has identified unconsolidated streamlaid deposits along the valley of Flume Gulch. All of these alluvial materials are located downstream of the proposed mining at the Trapper Mine. In fact, within this 5-year permit term, mining will not encroach upon any portion of the Flume Gulch drainage area. Land use along Flume Gulch consists of undeveloped rangeland and cropland. None of these crops are currently or were historically flood irrigated. Original data submitted by the applicant indicated that depths to the alluvial water table are shallow enough (about 2 feet) for the alfalfa to be subirrigated. More recent data shows the depths to ground water to he much greater (at least 6 feet). Based on the original data the Division determined that Flume Gulch is an alluvial valley floor. At this time sufficient data has not been submitted by the operator to refute this finding. Therefore, Flume Gulch is still determined to be an alluvial valley floor, The boundaries of the AVF are shown on Map M35A of the permit application. No portions of the AYF are proposed to be physically disturbed by mining in this 5-year permit renewal term. Potential impacts to the Flume (;inch AVF are discussed later in this document. Prior to mining in the Flume Gulch drainage or in the vicinity of the drainage during future permit terms, all issues relating to this AVF must be resolved. The Yampa River valley meets the requirements to be classified as an AVF, That is, it contains unconsolidated streamlaid deposits and sufficient amounts of water to be utilized for agricultural activities. Land use along the Yampa River valley consists primarily of irrigated hayland and pastureland. Cropland is both flood irrigated and subirrigated. It is unlikely that the Trapper Mine will impact the Yampa River AVF. This is further discussed later in this document. The Williams Fork River valley also meets the requirements to be classified as an AVF. There are agricultural activities including flood irrigation -18-