2002-07-03_PERMIT FILE - M2002004

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Exhibit D • 2. The blasting pattern will vary as to the particular limestone geology. It is anticipated, however, that a 12 ft x 15 ft x 30 ft (average depth based on thickness) pattern will be acceptable within the previously described weekly production panels. Patterns may range from 10 ft to 20 ft spacing and burdens. Hole depths will range from 10 to 40 ft, depending on limestone thickness. The licensed blasting contractor will be responsible for compliance with all applicable regulations, following the required limits in blasting procedures and materials. The blasting contractor will be required to implement management practices that will reduce the possibility of ANFO being spilled or otherwise exposed to water and subsequent dissolution. 4. Seismic monitoring will be conducted as necessary to insure that vibration limits are not exceeded. A pre-blasting survey will, be conducted on any structure within one-mile of the property boundary for which the owner has requested a survey in writing. No blasting will occur: • Within 50 ft of a buried telephone cable. • Within 1,500 ft of a dwelling. • At night. • Within 1,000 ft of a public road. 6. The licensed blasting contractor will provide all supplies and materials and load and blast shots. • Each successive excavation within a yearly block will be designed to produce approximately 75,000 tons of limestone after the unconsolidated material and shale have been removed. The drilling pattern will usually be 12 feet by 15 feet to a depth of the bottom of the limestone plus up to 6 feet of the Codell Sandstone at the base. The actual depths will be dependent upon limestone and sandstone thickness. The drill will be rigged with a dust collector and will use water to reduce dust emissions. Each blast hole will be stemmed with drill cuttings and dirt according to standard industry practice, typically to a minimum of 25 to 30 percent of the hole depth from the surface, to prevent surface blast. Each blast hole will be approximately 4 to 6 inches in diameter. The blasting agents and delay devices will be installed only by a licensed blasting contractor. Prior to blasting, an inspection of the blast site will be made to ensure that no persons are within the blast area, and the proper signals will be sounded. A scraper will typically be used to remove shale and unconsolidated materials, including topsoils (A and E-horizons) and subsoils (AC and B-horizons), that will be temporarily stockpiled in designated storage areas (refer to Exhibit D-1) within or adjacent to each 5-Year production panel for re-application to the mined area. Where appropriate, trucks may be utilized to supplement scraper excavation. Wherever possible, topsoil and subsoil will be directly placed onto regraded overburden surfaces, via an in-pit ramp from the pre-strip area to areas of active reclamation. An exception to this occurs in the area of the central conveyor/access road/ditch corridor, which will remain open until completion of mining in each panel. Each 1-Year production block will be reclaimed by placing the overburden material on the pit floor stripped from the adjacent panel subject to active quarrying and then reapplying the subsoil and topsoil, except for the conveyor corridor, which will remain open until mining is completed in each panel. Similarly, secondary access roadways along each side of the reclaimed spoils will be reclaimed following the cessation of mining in each panel. Portions of the second year block, and areas alongside the • conveyor/face access road may be covered by stockpiles of shale/unconsolidated materials and/or 1180-Mine Permit Exhibits (Jul.03.02)FINAL.dOe D-4 July 3, 2002