Innovation and perseverance: breaking new ground in hard-rock shaft sinking in the 1990s

"This paper describes the simultaneous sinking and equipping of a 4.9 m diameter concrete-lined shaft to a projected depth of 1660 m. The shaft blast design utilizes the full face method using a parallel hole burn cut. Hydraulic drilling and a totally redesigned Cryderman-type mucking unit were integrated into the four deck sinking stage to provide for drilling, mucking, concreting and shaft steel equipping operations. A safety program was tailored and implemented specifically for this shaft sinking project.IntroductionIn July 1988, Falconbridge Limited commenced development of its Thayer Lindsley exploration site located some four km north of Sudbury on Regional Road 80.The first phase of this project was awarded to J .S. Redpath Mining Consultants Limited and the scope of work included the engineering and project management to construct a surface plant capable of supporting a shaft sinking and exploration program for potential future mine development. This initial phase of the project was completed on schedule and under budget on December 23, 1988, and is the subject of an independent paper.In November 1988, J.S. Redpath Limited was awarded the shaft sinking and exploration phase of this project. The scope of work consisted of sinking and equipping a 4.9 m diameter shaft to a depth of 1660 m and carrying out the development and diamond drilling on two levels. This work was scheduled to be completed by November 1991.The T .L. Exploration Project is located toward the eastern end of the south range of the Sudbury basin, north of Sudbury. Figure 1 details the projected mining area and the shaft location on the geological complex. Figure 2 is a section showing the exploration shaft that is located in the Norite. Two levels will be developed from this shaft, on the 1310m and 1588 m levels, to provide access for further geological examination of the ore bodies."