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• 2.05.6(6) <br />This data provides significant validity to the Operator's position that no <br />subsidence protection will be provided for springs or ponds unless they are a <br />decreed water right and only then if the spring or pond has an overburden <br />depth of less than 800 feet. <br />Sheep Corral spring and pond SP-34-11 were undermined by the D-Seam <br />during October 2003. The overburden at this location is slightly over 1,000 <br />feet. There was no apparent damage to the spring and pond based on <br />monitoring results since the spring and pond were undermined. <br />A report presented in Volume IIIA, Exhibit 17 provides a prediction of surface <br />deformation resulting from longwall mining in the Dove Gulch Area. Trough <br />type subsidence in predicted over Dove Gulch. The predicted maximum <br />subsidence near the center of the panels is 9 feet. Predicted tensile strains <br />reach levels that can cause surface fractures. Most surface fractures will <br />occur on the eastern side of the panels where shallow overburden is present. <br />The springs and ponds in Dove Gulch are located in high overburden areas <br />S so surface fracturing should be minimal. The Dove Gulch pond, SP34-2, is <br />located near the center of panel B-11 at an overburden depth of 1,375 feet <br />which should minimize the risk of damage to the pond. <br />(f)(iii) A narrative of the detailed description of the measures to be taken to prevent <br />subsidence from causing material damage or lessening the value or <br />reasonably foreseeable use of the surface follows: <br />(f)(iii)(A) <br />The anticipated effects of planned subsidence are explained above and are <br />presented in detail in Volume IIIA, Exhibit 15, 17 and 21. <br />(f)(iii)(B) <br />The measures to be taken in the mine to reduce the likelihood of subsidence <br />are explained above. The mine plan will leave support pillars under Pond P- <br />1,adjacent to Hubbard Creek and near the outcrop. The long term stability <br />of the support pillars were evaluated in Volume IIIA Exhibit 15, Section 1.9. <br />The pillars in the bleeder entries along Hubbard Creek have a calculated <br />factor of safety of 4.3. To assure long term stability, a pillar must have a <br />factor of safety of 1.5 or greater. No backstowing or backfilling of voids will <br />• be performed. <br />PR-11 <br />2.05 - 115 - <br />11 /08 <br />/3 ~PReV~~ <br />~ ~-~ 19/a g <br />