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Telephone Service • The telephone service line pazallels County Road 33 and was not impacted by undermining and subsiding the line. The backup plan, in the event the line was severed, was to mobilize a repair crew can be mobilized to perform the required repairs and reestablish phone service. TCC is a user on this line and any disruption to its service would trigger mobilizing the repair crew. Therefore, additional monitoring of this line was not conducted. Railroad The Union Pacific Railroad (formally the Southern Pacific Railroad) spur traverses panels 7 Right through 9 Right of the 1993 - 1998 five-yeaz permit. The overburden thickness various from 1,150 to 1,200 feet in the corridor where the railroad passes over the mine workings. The railroad was subsided, and, prior to subsiding the line, a repair plan was developed by representatives of the railroad and the mine. The location of the rail line is shown on Map 23B, Structures and Renewable Resources. The worst-case impacts due to subsiding the railroad track could result in a train derailment. TCC successfully undermined the rairoad in the above mentioned panels without causing any derailments. The agreement letter allowing the mining is presented in Exhibit 7D-1. Foidel Creek Foidel Creek flows in a generally northern direction through the Eastem Mining District. At the extreme northern corner of panel 9 Right, the creek is outside of the panel and its angle of draw. The creek traverses through the northern half of panels 8 Right and 9 Right, as is shown on Map 23. The overburden thickness varies from 850 to 1,000 feet in the corridor where the creek passes over the mine workings. The projected impacts to the creek are presented in Exhibit 7E, Prediction of Subsidence, Eastern Expansion to the Foidel Creek Mine, and in the Probable Hydrologic Consequences section of this application. As noted in Exhibit 7E, subsidence varies from 0 to 67 inches over these panels. The type of subsidence that occurred, i.e. trough-shaped, ponding did occur, and this merely increased the amount of reparian habitat along the creek. Prior to full extraction mining under the creek, a channel survey was completed to enhance the information used in the prepazation of the probable hydrologic consequence section of the permit. The channel surveys have been updated in the semi-annual subsidence surveys submitted to the Division. These updates address the segment of Foidel Creek overlying panels 4 Right , 8 Right, and 7 Right. TCC has subsided a segment of Foidel Creek during the mining of panel 9 Right. As predicted, a small pool of less than 1 acre has developed in this reach of Foidel Creek. During the subsiding of the creek overlying panel 9 Right, flow in the creek was disrupted for approximately 8 hours. The inspection of Foidel Creek showed that the Twentymile Sandstone outcrop intercepted the creek. At one location a crack was noted and is postulated that surface flow in Foidel Creek was disrupted due to surface water entering the fractured sandstone. This disruption of flow was verified by visual observation of flow upstream and downstream of Panel 9 Right. It was noted that flow in Foidel Creek entering the 9 Right Panel was not exiting the subsided area over the panel. Again, this was observed for approximately 8 hours, and based upon the flow monitoring work it took approximately 66 days for the inflow and outflow from the 9 Right Panel to equilibrate. This data is presented on Table 72, Foidel Creek Subsidence Flow Monitoring. . A visual observation conducted during March 1997 revealed that the stream bed is sealed and inflow and outflow are approximately equal. The pool remains in place with no visual evidence of sinkholes or deep-seated cracks acting as conduits moving water out of the creek. The semi-annual subsidence report contains the pre- and postmining channel profiles. ~.~~m©qIr''~ APR 2 4 2000 Permit Renewal No. 3 2.05-180 11/1/99