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Transit Mix Concrete Co. <br /> 444 E.Costilla Street, Colorado Springs,CO 80903 Office: (719)475-0700 Fax: (719)475-0226 <br /> • With the primer(s)positioned in the hole, the bulk explosives are loaded using the <br /> following techniques based on hole condition. <br /> o If the hole is wet, the end of a hose, approximately 100 feet long, is <br /> lowered to bottom of the drill hole and a 100 %bulk emulsion blasting <br /> agent is pumped in starting at the bottom of the drill hole displacing the <br /> water in the hole. The blaster monitors the amount of bulk explosive using <br /> a measuring tape. The amount of bulk explosive loaded is recorded by a <br /> computer on board the truck. <br /> o If the holes are not directly accessible by the bulk explosive truck, the hose <br /> is moved from hole to hole. If the holes are wet the same procedure is <br /> followed as noted above. (i.e., a hose lowered to bottom of the drill hole) <br /> Should the holes be dry,the 100 % straight bulk emulsion explosive is <br /> loaded from the top of the hole. The blaster monitors the amount of bulk <br /> explosive using a measuring tape. The amount of bulk explosive loaded is <br /> recorded by a computer on board the truck. <br /> o If the holes are dry and directly accessible by the bulk explosive truck, an <br /> emulsion and ANFO blasting agent blend (Heavy ANFO) will be used. The <br /> emulsion/ANFO blend is augured into the top of the hole directly from the <br /> blasting truck. The blaster monitors the amount of bulk explosive using a <br /> measuring tape. The amount of bulk explosive loaded is recorded by the <br /> truck operator. <br /> • By design, the bulk blasting agent load does not completely fill the blast hole. A <br /> planned portion of each hole is left empty during the bulk explosive loading. This <br /> empty area in each hole is filled with stemming material (crushed stone). The <br /> stemming material is used to contain the explosive energy on detonation and <br /> allow the energy to break the rock. Only crushed stone will be used as stemming <br /> material for blasting operations at the Hitch Rack Ranch operation. Stemming <br /> material reduces the possibility of flying rock above the bench and reduces the <br /> overpressure (noise) from the blast event. <br /> • During loading of the drill holes, none of the Nonel detonators in the holes are <br /> inter-connected to one another. <br /> • After placement of the stemming material, the final step in the loading procedure <br /> is to connect each of the Nonel detonator lead lines (shock tube) extending out of <br /> the stemmed holes together. Nonel surface delays are used to make these <br /> connections and are placed between the holes and rows of holes. These surface <br /> delays have preset delay firing times that provide the desired blast timing between <br /> the holes and rows of holes so that they initiate sequentially one or two holes per <br /> 8 ms delay. <br /> • To reduce the chance of misfire, two paths will be provided for each surface delay <br /> connection. All connections will taped as visible assurance that all holes have <br /> been tied in. A safety line consisting of trunkline (Nonel shock tubing) will be <br /> connected to the last hole in each row and will extend beyond the blast site to <br /> check for complete detonation of each row. <br /> 9 <br />