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Information provided in application Exhibit 16 (Soil Mapping Unit Descriptions) and backhoe pit data provided on Page 2.06 -9 show that a number of alluvial soil types exhibit late growing season ground water elevations within 6 feet of the surface. Hay crop species commonly grown in the Yampa Basin would be expected to derive benefit from ground water when present at such depths. The major vegetalion type on the Fish Creek AVF within the proposed permit area is a sagebrush meadow community dominated by silver sagebrush with a number of sedge and rush species contributing significantly to the community. All of these species are hydrophvtes typically associated with subirrigated conditions. The Division received a letter from one of the surface owners, Mr. Edward Camilletti , on January 23, 1998, regarding the significance of the Fish Creek AVF to farming in sections 10 and 15, TSN, R86W. The Camelletti's use these lands as undeveloped rangeland. The landowner estimated that 1% of the ranch production is attributed to the Fish Creek AVF. Twentymile Coal ompny o s a significant portion of the lands in and adjacent to the Fish Creek AVF. TCC opera cattle operation on these lands and manages the land, through its ranch manager, Trout Creek Ranch, as undeveloped rangeland. TCC does not utilize the Fish Creek AVF as cropland. TCC projects that impacts to the Fish Creek AVF will not significantly impact the cattle operation. Twentymile Coal Company will not be undermining the Fish Creek AVF as a result of the proposed decision for PR04. Therefore, the Division finds the proposed mining operations will not interrupt, s discontinue or preclude farming on the Fish Creek alluvial valley floor. (Section 4,24.3(1)). TR-14 approved the undermining and subsidence of a small portion of Fish Creek due to longwall extraction in panels 5, 6 and 7 in the Southwest Mining District. No farming activities are curtently undertaken along Fish Creek in this area. Subsidence would not preclude the farming of this area. 2. The proposed mining operations would not cause material damage to the quantity and quality of surface and ground water that supply the alluvial valley floor. The potential for subsidence cracking at the surface and subsequent interception and reduction of flow in Fish Creek is minimal. Depths of subsidence cracks produced by tensile stress are generally less than 50 feet. Due to the presence of thick, fine-grained sediments in this area, significant surface cracking is not anticipated. Any cracks which may develop in the stream channel will rapidly heal as alluvial materials collapse in the voids and stresses are relieved due to adjacent subsidence movements. Mining has been completed in section 25, TSN, R87W. Hydrologic monitoring data and analysis for this area are included in Exhibit 7j of the permit application. An analysis of the data collected is also included. No changes in Fish Creek flow volumes in lower Fish Creek were observed. Twentymile Coal Company will not be undermining the Fish Creek alluvial valley floor as during the PR04 proposed mine plan (permit map 23), continuing mining in longwall panels 6R through 2R in the Eastern Mining District ~ The Fish Creek alluvial aquifer should not be affected due to its fine-grained nature and the nearly 100( feet of separation from the mine workings. Alluvial wells showed slight impacts (see GWAP-7) but it is not clear whether these small water level chanties are due to water loss to the bedrock below or to re- consolidation of the alluvial body. Regardless, no changes in Fish Creek alluvial water levels in lower Fish Creek have occurred. 22