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SECTION 2.05.3(6)(a) <br />BLASTING <br />2.05.3(6)(a) Surface Blasting Plan <br />Prior to removal, the overburden, parting, and/or coal must be fragmented to a size which can be <br />handled efficiently by excavation equipment. The majority of the fragmentation will be <br />accomplished by the use of explosives. The objective of this process is to provide fragmented <br />overburden, parting, and coal ahead of excavation and loading equipment, and to meet the <br />requirements of Rule 4.08. <br />2.05.3(6)(a)(i) Explosives and Design of Blasts <br />Experience at the New Horizon North Mine indicates a high percentage of the blast -holes contain <br />some amount of water. WFC has settled upon the use of: a) bagged gel products in conjunction <br />with ANFO in plastic sleeved holes for slightly to severely wet holes, and b) straight ANFO for <br />the dry holes. Typical poundage of explosives used per hole will range from 1-600 pounds of <br />ANFO/bagged-gel for full bench production blast, 1-250 pounds of ANFO/bagged-gel for deck <br />shots and 1-40 pounds of ANFO/bagged-gel for parting shots. It is not unusual to use all of the <br />methods listed above, along with loading conventional straight ANFO in dry holes in a single <br />overburden blast pattern. <br />Powder factors will vary with each shot due to ever changing geologic rock formations. Powder <br />factors for each shot will be selected after the following criteria have been taken into <br />consideration: <br />• Examining the highwall for geologic rock formation thickness and rock type. <br />• Consult with the blast -hole drill operator for hardness of the rock and thickness <br />within the proposed blast area. <br />• Consult with the overburden shovel operator for size of blasted rock and ease of <br />digging. <br />• Location of shot in relationship to dwellings and other structures. <br />Drilling patterns will vary in burden and spacing dimensions dependent on site specific <br />conditions for each blast. Typically, burden spacing will range from 10 to 15 plus feet, and <br />spacing will vary from 15 to 20 plus feet. Burden and spacing dimensions are governed on drill <br />bit size (5.25 to 7 inch diameter), hardness of rock and degree of fragmentation desired. Normal <br />production blasting will be a rectangular pattern with on -echelon delays. Staggered patterns have <br />been used in the past with success and will be used in the future as conditions warrant. Stemming <br />Section 2.05.3(6)(a) Page - 1- December 2015 (TR -12) <br />