Shaft-sinking at Nickel Rim South
Building the Nickel Rim South nickel-copper mine is a major development for Noranda-Falconbridge Ltd. in the Sudbury Basin of northeast Ontario. The job commenced in March 2004, when funding was approved. An article in CMJ February 2005 described the whole project. For details about the sinking of the shafts we interviewed project manager Rick Collins.
CMJ: What is the shaft-sinking method? Are any new technologies being incorporated in this job?
Collins: The two shafts (the 7.6-m-diam production shaft and the 6.1-m-diam ventilation shaft) are being sunk from surface to a depth of 1,750 m using the mechanized drill and blast method with multi-level suspended Galloway staging (50 tonnes for the ventilation and 100 tonnes for the production shaft). The rock is drilled by suspended multi-boom jumbo drills and removed using Brutus mucking jaws and 15-tonne sinking buckets. Five hoists service the shafts (three in the production and two in the ventilation shaft hoist houses), with ropes directed over steel headframes that are 49 m high over the vent shaft and 67 m high over the production shaft. Concrete for the cast-in-place lining is delivered by buckets and slick lines in the ventilation and production shafts, respectively. The production shaft is fully equipped with steel and permanent services from an equipping deck, which is suspended independently within 25 m of the Galloway top deck. The ventilation shaft is being sunk equipped with the necessary services for sinking only: power, communications, compressed air, water, ventilation, auxiliary-hoist guides and dewatering pipes.
CMJ: The two shafts that are being sunk concurrently are only 50 m apart. Why is this uncommon practice in Sudbury?
Collins: It’s simply been a long time since two shafts were sunk simultaneously in the Sudbury area. The more conventional approach is to sink an exploration shaft first, drill off the orebody and then sink the second shaft for production purposes once the orebody has been proven.
CMJ: In what ways have you “raised the bar on safety” in this job? What are the safety statistics to date?
Collins: Hatch in alliance with McIntosh Engineering (“HMA”) has an EPCM contract to deliver the Nickel Rim project according to Falconbridge’s feasibility study. Success is measured by safety, schedule and cost performance; but right through the project, fromFalconbridge to its contractors, safety is treated with paramount importance.
Our project safety statistics after one year and 950,000 person-hours are: 0.4 lost-time incidence frequency, 2.8 medical aid frequency, and 1.1 reportable injury frequency. These values stand at around 50% of our targets and, as our goal is zero accidents, we are continually trying to improve this performance.
We are raising the safety bar commencing with rigorous orientation sessions for every person who enters the property unattended, given by various senior members of the project team. Two thousand people have gone through this orientation in 12 months. There are regular safety talks and workshops (both on-site and off-site) and daily contractor co-ordination sessions, a toolbox meeting prior to shifts and a safety discussion at the outset of all project meetings. We also recognize safety success milestones with events such as barbecues and lottery tickets for the entire site team.
CMJ: How about the cost and schedule performance so far?
Collins:The project completed 2004 scope, on plan with a project cost performance index of 1.01 and schedule performance index of 1.00. The project is currently progressing into the shaft-sinking phase and remains on plan.
CMJ: Tell me about Falconbridge’s alliance with the shaft-sinking contractor. How has that been useful in speeding up the process? Are there other advantages?
Collins: Falconbridge has entered into an ‘alliance’-style contract with Cementation Canada for the design and sinking of the two shafts. This contract was secured competitively during the pre-feasibility phase. The intention was to make available, at an early stage of design, the sinking expertise, costs, schedules and engineering details of the shaft-sinking equipment that have a direct effect on the design of the permanent shafts, headframes and hoisting systems. Early involvement of this expertise helped the team develop a solid plan and establish the necessary surface and underground infrastructure for commencing shaft-sinking within 12 months of project approval.
CMJ: What are the ongoing aspects of the performance management (the “metrics”) that are being measured and reported on? How does this influence the progress of the job?
Collins: We have been tracking all the 22 principal surface contractors by earned value on a weekly basis; this allows us to make early recognition of when an element of the project is running into trouble, allowing maximum time for adjustment of the plan. We are now tracking all aspects of the shaft-sinking cycles from drilling times to explosive loading, muck (rock) removal, lining concrete, installation of services, planned and unplanned maintenance times. These times and resulting trends will be compared with established baselines in an effort to optimize efficiency of the sinking sycles.
Rick Collins is the project manager for the Nickel Rim South mine deposit definition project. He can be reached at [email protected] or tel. (705) 693-2761, ext. 3141.