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area is currently used for grazing. The area immediately upstream from the former reservoir site is <br />currently used as a grass hay field. <br />These fields are located in the upper reaches of Sage Creek, and therefore are not typical of alluvial <br />valley floors in this area with agricultural potential. However, the upper field (approximately 10 <br />acres) is currently being farmed for hay, and the second field has the potential to be put to use as a <br />sub -irrigated hay field. Furthermore, during a site visit on May 19, 1995, the upper grass hay field <br />was being flood irrigated by means of an irrigation ditch along the eastern edge of the field. Due to <br />the existence of flood irrigation and the presence of sub -irrigation of the unconsolidated stream laid <br />deposits in the fields immediately upstream from the past Sage Creek Reservoir, these fields are <br />determined to be alluvial valley floors. <br />The field just above the breached Sage Creek dam is dissected by the streambed. This area is <br />undeveloped rangeland that is currently used for grazing. The limited size of the field would make it <br />difficult for farm equipment to operate. This field is not typical of agriculturally productive alluvial <br />valley floors in this region. <br />Land management information and farm productivity values for the hayfield in Section 18 are <br />provided in Exhibit 16-3 of the PAP. The field in Section 18 is the smallest of three fields managed <br />as part of a limited sheep ranching operation. Dominant grass species in the field are Bronius inermis <br />(smooth brome), and Poa ammophila (bluegrass). The field produces one hay cutting per year at a <br />maximum rate of 2 tons/acre for a maximum production of 20 tons/year. The maximum annual <br />production from the total ranching operation is 150 tons. The field in Section 18 provides 13% of the <br />total productivity. The estimated worst-case loss in productivity is 2.8% as shown on Table 17-17a <br />of the PAP. Crop reductions were based on the formula presented in the Material Damage <br />Assessment Process Pertaining to Alluvial Valley Floors, Surface Water, Ground Water and <br />Subsidence at Coal Mines (January, 1988). As referenced in this document, less than a 3% reduction <br />is considered insignificant. <br />Sage Creek "Flood Irrigated Alfalfa Fields" <br />The Yoast Mine permit application package documents the presence of approximately 86 acres of <br />flood irrigated alfalfa hay along Sage Creek in Section 30. Five to ten acres of alfalfa were flood <br />irrigated in this field from 1988-1992. The field was irrigated by means of pipes spreading water <br />from a small reservoir near Sage Creek. The reservoir does not currently impound water because the <br />dam is breached. The field was converted to diyland wheat. Water availability for irrigation was <br />marginal; however, future restoration of the dam and flood irrigation of the field is a remote <br />possibility. The creek typically dries up in July or August. <br />It is unlikely a reservoir in Sage Creek will be reconstructed in the future. Two previous attempts to <br />construct dams have failed and the increased engineering specifications and economics involved in <br />rebuilding the dam would be significant. Without the dam, water availability is insufficient for flood <br />irrigation. The Division agrees with SPL's assessment of water availability in Sage Creek and finds <br />that the area has no potential for successful irrigation. <br />The Division finds the field in Section 30 meets the regulatory definition of an alluvial valley floor <br />because it may be sub -irrigated. However, only a minor portion of the alluvial valley floor is sub- <br />irrigated, according to Exhibit 16-3 of the PAP. Furthermore, the field is seven miles downstream <br />from the nearest discharge point for potential spoil springs. Therefore, the potential for material <br />damage to the quality of water supplying ground water to the alluvial valley floor is insignificant. <br />Permit Number C-1994-082 Page 20 of 23 <br />