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-9). Hay crop species commonly grown in the Yampa Basin would be expected to benefit from such <br />shallow ground water. <br />The principal vegetation type in the Fish Creek AVF within the permit azea is a sagebrush meadow <br />community dominated by silver sagebrush, with a number of sedge and rush species contributing <br />significantly to the community. All of these species aze hydrophytes typically associated with <br />subirrigated conditions. <br />The Division received a letter from one of the surface owners, Mr. Edwazd Camilletti , on January 23, <br />1998, regazding the significance of the Fish Creek AVF to farming in sections 10 and 15, TSN, <br />R86W. The Camellettis use these lands as undeveloped rangeland. The landowner estimated that 1% <br />ofthe ranch production is attributed to the Fish Creek AVF. <br />Twentymile Coal Company owns a significant portion of the lands in and adjacent to the Fish Creek <br />AVF. Twentymile Coal Company operates a cattle operation on these lands and manages the land, <br />through its ranch manager, Trout Creek Ranch, as undeveloped rangeland. TCC does not utilize the <br />Fish Creek AVF as cropland. TCC projects that impacts to the Fish Creek AVF will not significantly <br />impact the cattle operation. <br />TR-14 approved the undermining and subsidence of a small portion of Fish Creek due to longwall <br />extraction in panels 5, 6 and 7 in the Southwest Mining District. No farming activities are currently <br />undertaken along Fish Creek in this azea. Subsidence would not preclude the farming ofthis azea. <br />2. The proposed mining operations would not cause material damage to the quantify and quality of <br />surface and ground water that supply the alluvial valley floor. <br />Fish Creek is the only AVF proposed for undermining during PR-06 mining. TCC predicts the <br />mining proposed in PR-06 will cause little or no adverse impacts to water in Fish Creek or its <br />alluvium (Exhibit 7e-6 of permit application). TCC predicts minimal potential for water-loss from <br />subsidence-caused surface fissures and associated "stream pirating". Neither surface fissures nor <br />stream pirating were found during previous undermining of Fish Creek by panels 13 Right and 14 <br />Right. <br />The only significant degradation of stream water from TCC's mining operations has been caused by <br />pumping of underground mine water into Fish Creek and Foidel Creek. Data in TCC's annual <br />hydrology reports document this degradation. Pumping occurs at two sites, 115 (Fish Creek borehole) <br />and 109 (portal azea). The pumping loads the streams with dissolved solids, mainly sulfate. The <br />operator has maintained stream water quality below the material damage threshold by limiting the <br />pumping rates at both sites and treating the pumped water at one of the sites, 115. The operator <br />proposes in PR-06 to continue to limit pumping rates and treating water as in the past; therefore, mine <br />pumping can be expected to not cause material damage to the quality of surface water or alluvial <br />water. <br />Water in Fish Creek could see a slight increase in sediment load as subsidence slightly changes the <br />stream channel gradient and minor erosion occurs at head cuts in the stream channel. This increase in <br />sediment load should be no more than what is observed during high spring runoff and after lazge <br />rainstorms. An increased sediment load was not detected during past subsidence of Fish, Foidel, and <br />Middle Creeks. <br />No impact to groundwater quality is predicted. Ground water could flow between aquifers through <br />subsidence fractures. The Fish Creek alluvium and the Twentymile sandstone have the greatest <br />28 <br />