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equipment is disabled near a highwall or spoil bank, precautions will be taken to ensure that personnel are removed safely and that repairs, and or re -location of the equipment is conducted in a safe manner During the excavation of a pit, isolated structurally unsound materials may be exposed in the highwall. In these areas, highwalls can be sloped at a flatter angle to reduce the possibility of failure. Whenever practical, personnel and equipment will perform work perpendicular rather than parallel to the highwall. When dipline drilling (which may orient drills parallel to the highwall) is required near the crest of a highwall, protective measures will be utilized to ensure the safety of personnel and equipment. These measures will include establishing berms at the crests of the highwalls prior to commencing work to ensure safe distances from the crest are maintained for equipment working in this vicinity, orienting equipment as perpendicular to the highwall as possible given the constraints of cross -slope stability limitations for the equipment involved (drills), and utilizing buffer blasting where possible to reduce the need for drills to work near the crest of a highwall. In instances where small areas of the highwall are jagged and possibly unstable, the dragline operator will attempt to scale the highwall with the bucket. In cases where the dragline cannot reach the area, other methods may be used to eliminate overhangs or other sections of the highwall that do not appear to be stable as per 30 CFR Part 77.1005. High walls that are deemed to be hazardous will be barricaded with berms or orange cones to limit access to, or near, these areas. When box cuts are made, necessary precautions shall be taken to minimize the possibility of spoil material rolling into the pit, in accordance with 30 CFR Part 77.1002. All spoil piles have an approximate angle of repose from 1.25H:1 V to 1.33H:1 V. Where conditions permit, spoils may be re -cut at 1 H:1 V. These angles are used in conjunction with box cut and general pit design. Cross Section 1 - Stdkeline Mining Method, and Cross Section 2 - Dipline Mining Method, show representative highwall and spoil slopes. Pit widths may vary from 80 to 280 feet. Access ramps for the pits are constructed on both the highwall a sides. f�C$ED/FILED AUG 2 6 2016 Drilling (and related activities): CMSH-DISTRICT 9 The operational safety and overall stability of drills and any associated equipment working in support of drill and blast activities, are addressed by adhering to the equipment manufacturer's guidelines and established safe work procedures. In dipline drilling operations (with the drills parallel to and at the toe of existing highwalls) drilling of the first row of holes adjacent to a highwall toe will be accomplished during daylight hours after a thorough inspection of the highwall is completed. S:\GROUND CONTROLUanuary 2016 GCP Revision\Trapper GCP_Jan2016_DRAFT1.docx Page 15