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provided during mining. This is based upon TCC's extensive experience in the $MD and the utilities not wanting • to construct alternate feed lines azound the panel. Union Pacific Railroad (formerly Southern Pacific) The railroad track will be undermined and subsided by TCC's mining of Panels 17 Right and 18 Right. The subsidence predictions for the railroad track aze presented in Exhibit 7e-8, . The maximum subsidence predicted for the panel is approximately 67 inches. Subsidence of the track will require re-leveling the track, to the extent required, to insure no disruption of service to the mine. Ballast will be stockpiled or hauled in to be used in this work. If required for the creek crossings, fill material may be brought in from material that the UP has stockpiled during its normal maintenance activities. The material will be placed and remain until the UP removes the Energy Spur. No significant impact is anticipated to the track after the repair work is completed. This is substantiated by TCC's experience with re-leveling the track that passed over panels 9 Right through 7 Right, 12, 13 and 14 Right. Aquifers The Twentymile Sandstone is the only lazge regional aquifer that is above the coal seam. It is not anticipated that any wells will be impacted from the undermining of the Twentymile Sandstone. The present hydrologic monitoring program conducted by Twentymile Coal Company does not show any impact to this formation outside of the mining area. Therefore, it would be prudent to predict no off-site impacts to this unit. Fish Creek Twentymile Coal Company is not anticipating any material damage or diminution of use to Fish Creek. Exhibit 7e-6 contains the subsidence predictions for the creek. TCC has gained a great deal of information on Foidel Creek, Middle Creek and Fish Creek as a result of mining in the EMD, SWMD and the NMD (panels 12 Right through 16 Right). Except for the one isolated period of stopping the flow in Foidel Creek for a period of 8 hours, no further damage has been observed in the creek. Likewise, there has been no interruption of flow in Fish Creek during mining of panels 12, 13 and 14 Right. The same response of the creek is anticipated as mining progresses in the Northern Mining District (panels 17 and 18 Right). Fish Creek AVF The Fish Creek alluvial valley floor will be undermined and subsided by panels 17 Right and I8 Right. The location of the AVF in relation to the panels is shown on Maps 23 and 23B. The azea that TCC is proposing to undermine in the Fish Creek drainage is located in parts of sections 10 and 1 I of TSN, R86W is identical to the area that P&M Coal Company was planning on undermining and subsiding in its proposed Fish Creek Mine. P&M contracted with the consulting Firm of Kaman Tempo to prepaze a report responding to the requirements of Rule 2.06.8(4). This report has been incorporated into Exhibit 7-e2. The conclusions presented in the report agree with TCC's opinion that subsidence of the alluvial valley floor will not materially damage the existing ranches. It should be noted that the Kaman Tempo report was prepared in 1982 and since that time the management practices have not changed, i.e. large acreage ranches to meet the economic requirements of the marketplace. This ownership pattern continues in the Twentymile Park basin. The owners of the sections to be subsided include the State of Colorado and Camilletti and Sons. TCC contracted with SubTen•a, Inc. to expand the subsidence predictions to further evaluate impacts to Fish Creek and its alluvial valley floor. This report is presented in Exhibit 7e-6, Twentymile Coal Company, AVF Subsidence Study, Final Report. The results of the mathematical model show an additiona17.3 acres will be flooded as a result of mining in panels 17 and 18 Right during the low flow period. Dwing spring run-off up to 12.3 acres will be flooded. PR 03-06 2.05-184.8 05/07/03