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Exhibit ~ <br />• disturbed area where soil has been removed and no vegetation exists will be controlled <br />and minimized. <br />The highwalls at the northern edge and the sides of the earthen incline will be <br />permanently stabilized with slopes- not exceeding 70 percent for rock and 30 percent or <br />less for soil. Final highwalls will also be sloped 4H:1 V and stabilized to prevent erosion <br />with the use of a geotextile material containing the prescribed seed mix (or equivalent <br />methodology). Erosion and sedimentation controls, such as impoundments, silt fencing, <br />and diversion ditches, will be established to prevent soil erosion and siltation of streams. <br />It is proposed that impoundment of surface water be contained in the northwestern-most <br />corner of the initial box cut, its lowest elevation. This impoundment will be designed to <br />contain all runoff anticipated in a 100-yeaz storm event. The impoundment will migrate <br />with the mining as it moves to the south. This water will be used for dust control <br />whenever possible. Dust control measures will follow the dust control plan approved for <br />this operation. Dust suppression at the crusher will be implemented by water spray during <br />dumping, in a mostly enclosed dump hopper, and at conveyor belt transfers to maintain <br />dust within regulated levels. Water for dust suppression on roadways and in the removal <br />of overburden will be applied by water truck on a regular basis, as required. It is <br />anticipated that the actual application rate of water on road surfaces will be in the order of <br />0.03 inch equivalent per day. <br />Limestone blasting will occur about once per week, by a licensed blasting contractor <br />following standard practices. Most blasting will occur in limestone, but on infrequent <br />• occasions the overburden will require low-level blasting. A short summary of blasting <br />practices is listed below and discussed in the Rule 6.5 Appendix. <br />1. To achieve a powder factor of about 0.8 lb/ton, it is anticipated that <br />6.25-inch diameter holes will contain up to 360 pounds of blasting <br />agents (ANFO) and an accelerator, with an approved delay interval. <br />2. The blasting pattern will vary as to the particular limestone geology. It <br />is anticipated, however, that a 12 ft x 15 ft x 30 ft (average depth based <br />on thickness) pattern will be used within the previously described <br />weekly production panels. <br />3. The licensed blasting contractor will be responsible for. compliance <br />with all applicable regulations, using the required limits in blasting <br />procedures and materials. <br />4.. Seismic monitoring will be conducted in order to insure that the <br />vibration limits are not exceeded. Apre-blasting survey will be <br />conducted on the only dwelling located within one mile of the site. <br />5: No blasting will occur: <br />• Within 50 ft of a buried telephone cable. <br />. Within 1,500 ft of a dwelling. <br />AppEzltibitsA-T-APP(1180)RevB/January 17, 2002 D-4 <br />