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Amended Geotechnical Findings Foidel Creek Permit Application XVI. Explosives (2.05.3(b), 4,08) Colorado Yampa Coal Company proposes to conduct blasting operations within 500 feet of several potentially sensitive facilities, including subsurface gasoline storage tanks, an electrical substation and a 69,000 volt overhead electrical powerline. However, the applicant will exercise special precautions to clear the area of all personnel prior to blasting operation. Gasoline subsurface storage facilities will be precisely inventoried to detect any leakage which might occur. Stemming design should limit flyrock generation and blast loading will be limited to less than 440 pounds per 8 second delay. Vibrational analyses completed on the subject property have determined that this loading will limit peak particle velocities at the location of the critical storage facilities to less than 0.52 inches per second. The electrical substation and the 69,000 volt electrical powerline have been relocated, as depicted on Map TR-2a of the technical revision of Permit 79-177. The Division finds that the blasting plans within the Foidel Creek permit application conform with the requirements of Rules 2.05.3(b) and 4.08. XVII. Backfilling and Grading (2.05.3(61(bl. 2.05.3(9). 2.05.4(21(a The proposed Foidel Creek underground mine portals will be faced-up from an existiny surface mine pit low-wall. The applicant proposes to reconfigure the existing low-wall and the existing backfilled spoil slopes which comprise the opposite face of the existing surface pit. Exhibit 8 of the permit application presents thorough and prudent state-of-the-art stability analyses of an earlier, more extensive proposed reconfiguration for the surface facility area. The conclusions of this analysis are applicable to the amended, less extensive reconfiguration of the mine portal area depicted on Maps MR-1 and MR-4. The reader is referred to Section XXIV of these findings for a more detailed discussion of these geotechnical issues. Following cessation of underground mining within the Foidel Creek mine, the applicant proposes to backfill the existing surface pit portal facility area. Previously mined spoils existing within areas adjoining the surface facility area will be used to completely backfill the existing pit to the approximate original contour. -(ADD COMMENTS AT THIS POINT REGARDING HANDLING OF ACID OR TOXIC FORMING MATERIALS)- The applicant has requested a delay of contemporaneous reclamation within the surface pit area to facilitate the construction of the proposed Foidel Creek portals and the supporting surface facilities. The reader is referred to Section XXIV of these findings for a more detailed discussion of the delay of contemporaneous reclamation variance request.