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heat became an unacceptable working condition and the decision was made to cease operations until the new cooling system was put in place. They are com- pleting that system now and shaft sinking operations are expected to begin again this summer. Modern Shaft Sinking Techniques Similar to all mining projects, shaft- sinking operations require a lot of dedi- cated people to be successful, explained Tom Goodell, general manager-shaft development for Resolution Copper. A photo of all of the people working on the project was taken before Resolution Copper lowered the Galloway work stage into the shaft in 2008 and most of those locally trained people are still with the project today. "The No. 10 shaft is cur- rently at 6,630 ft, already the deepest shaft ever sunk in the U.S., and we still have 312 ft to go," Goodell said. Before joining Resolution Copper, Goodell spent five years as general manager for Macintosh Engineering and he also worked for 10 years with J.S. Redpath, as general manager of U.S. operations. All-in-all, he has participated in the design start-up, operation, and manage- ment of six large scale shafts and under- ground construction projects. The shaft-sinking production cycle consists of drilling, loading the holes, blasting, mucking, initial ground support, concrete lining, and the installation of utilities (pipe). "We have an overall setup that is designed to accomplish each of these cycles efficiently," Goodell said. "The key to it is a Galloway work stage." The Galloway work stage remains near the bottom of the shaft most of time. Embedded in the work stage are jumbo drills, mucking machines and the equip- ment for lining the shaft. "Almost every- thing we need is down there on this 160- ton, suspended-from-the-surface work stage," Goodell said. Drilling is accomplished by four fit- for-purpose drill rigs or jumbos. A jumbo with control console is lowered from the Galloway to drill a number of concentric holes. "The jumbos provide a high degree of accuracy," Goodell said. "You could not do this type of work with hand-held pluggers." Once the round is drilled, plastic tubes are inserted into the holes to pre- vent water and cuttings from entering the holes. The larger burn holes are not loaded giving the round a free face to break to during detonation. "The burn cut works quite well," Goodell said. "The blast goes straight up into the bucket well in the Galloway and doesn't do much damage to the structure. That's the theo- ry at least; the miners still seem to break things every once in a while. "We could pull 12 ft rounds in this rock, but we decided on 10-ft rounds because it fits our cycle," Goodell said. "We want a cycle every day. Two rounds equate to one 20-ft concrete pour." For blasting, Resolution Copper uses both bulk and packaged emulsion. Once they hit the water, they needed to use APRIL 2014 • E&MJ; 29 www.e-mj.com R E S O LU T I O N C O P P E R Diagram of vertical shaft muckers (VSMs) with a clam style bucket and pneumatically powered. Bulk and packaged emulsion non-electric and electric detonators. Inset: Resolution Copper No. 10 shaft full bench blast pattern plan. EMJ_pg28-33_EMJ_pg28-33 4/2/14 11:11 AM Page 29