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Teleahone Lines • The buried telephone lines aze not expected to be impacted by the mining operation. Twentymile has undermined and subsided a section of buried line in the Southwest Mining District and Eastern Mining District. In the event there is a disruption in service, i.e. line severed, Twentymile would become aware of it immediately as the mine is served by that line. If service were disrupted, a repair crew would be called out to service the line. The line was subsided by mining conducted in the 9, 8, and 7 Right panels without disruption to service. It is anticipated the lines will continue to respond to subsidence in the same fashion. 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. Foidel and Fish Creeks Twentymile Coal Company is not anticipating any material damage or diminution of use to either Foidel or Middle Creeks. Exhibit 7e-3 contains the subsidence predictions for both of the creeks. No material damage will occur to either of the creeks due to subsidence. TCC has gained a great deal of information on Foidel Creek and Middle Creek as a result of mining in the EMD. 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. The same response of the creek is anticipated as mining progresses in the Eastern Mining District. • Fish Creek AVF The Fish Creek alluvial valley floor will be undermined and subsided by panels 13 Right through 16 Right. The location of the AVF in relation to the panels is shown on Maps 23 and 23B. The area that TCC is proposing to undermine in the Fish Creek drainage is located in parts of sections 10, 11, 15 and 16 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 prepare 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 prepazed in 1982 and since that time the management practices have not changed, i.e. lazge acreage ranches to meet the economic requirements of the marketplace. This ownership pattern continues in the Twentymile Pazk basin. The ownership of parts of sections I S and 16, TSN, R86W has changed since the P&M study was completed. During the study period Mr. Perley Green owned the property and he subsequently sold it to P&M. P&M in turn sold the property to Log Creek Inc., who in turn exchanged the pazcel for other acreage owned by Twentymile Coal Company (formerly Cyprus Western Coal Company). Presently, the property is owned by Twentymile Coal Company. TCC contracted with SubTerra, Inc. to expand the subsidence predictions to further evaluate impacts to Fish Creek and its alluvial valley floor. This report is presented in Exhibit 7-e3, Northern Mining District, AVF Subsidence • Prediction. The report provides a numerical analysis of approximately 2000 cross-sections through the subsided area, and also used a 3D Geologic Modeling software program (GEMCOM) to compaze against the mathematical model. The results of the mathematical model show that of the 560 acres in the alluvial valley floor approximately 70-84 will be impacted by subsidence, during the low flow period. During spring run-off up to 210 acres will be PR 03-06 2.05-184.4 05/07/03