Multi-million dollar shaft rehabilitation for Compass Minerals’ Sifto Salt mine begins in January
Cementation Canada will be on familiar turf later this year as the North Bay mine builder has landed a major contract to rehabilitate the shafts at a Goderich salt mine.
Kansas-based Compass Minerals, the owner of the Sifto salt mine on the shores of Lake Huron, selected Cementation as part of a “multi-million dollar” contract to reline the walls of two shafts at the mine.
“Engineering is ongoing, we have a letter of intent in place and we’re working on a final contract,” said Cementation president Roy Slack. “Work on site is scheduled to begin in January.” Cementation sank the original No. 1 shaft in 1959, followed by a second shaft in 1968.
As many as 100 Cementation workers and sub-contractors will be required at peak periods during the three-year project.
The grouting process that will be used on the two shafts was patented by Cementation founder Albert Francois in 1914 to facilitate the sinking of shafts through waterbearing ground.
“We just finished a successful project for Potash Corporation in Picadilly, New Brunswick, where we sank two shafts through water-bearing ground with a complex liner,” said Slack.
In a news release, Compass Minerals president Michael Marksberry said Cementation presented a “good proposal” to address the upper portion of the shafts – the water-bearing zones – with a low-risk approach.
“The original request for proposal called for the removal of the existing lining and its replacement with a new one,” said Slack. “We thought that created a risk of water inflow, so we suggested a different approach. We said let’s leave the lining there and put a steel lining over it with a grout cement mix in- between.”
One of the shafts will be widened below the water-bearing zone to increase ventilation flow. The work will be sequenced to allow production to continue as there are three shafts at the mine.
“It’s nothing new for us,” said Slack. “We have to work closely with the operations group and minimize any delays.”
Besides installing new liners, Cementation’s subcontractors will remove an existing headframe and erect a new one.
The rehabilitation will allow Compass to meet its target of nine million tons of annual hoisting capacity. While other mining service companies have staggered through the global industry downturn, Slack said Cementation has remained quite active, especially in the U.S. Cementation’s early completion of an underground development contract at Lundin Mining’s Eagle Mine in Michigan’s Upper Peninsula allowed the company to go into production two months ahead of schedule. Work at the Eagle Mine has now progressed to contract mining.
At Kennecott’s Bingham Canyon mine near Salt Lake City, one of the biggest open pit mines in the world, Cementation collared a portal above the location of a recent landslide and excavated the ground to the old workings. The company is also working on a rain tunnel to help dewater the walls and excavating an exploration ramp to allow for underground mining.
Another U.S. contract has Cementation sinking a winz at Hecla Mining’s Lucky Friday mine in northern Idaho. In Ontario, Cementation still has remaining work at Vale’s Totten Mine in Sudbury, AuRico Gold’s Young-Davidson operations in Matachewan, and Goldcorp’s Hoyle Pond Mine in Timmins.
At the Young-Davidson mine, Cementation took an innovative approach, sinking a 5.5 -metre shaft using raiseboring as opposed to the conventional method of shaft sinking.
“We did it in two legs down to about the 900-metre level,” said Slack. ”There’s still one more leg to go to get them down to 1,500 metres, but they have started to use the shaft for production.”
Cementation is also deepening a second, historic shaft at Young-Davidson. Slack is optimistic about 2015.
“We’re seeing some projects coming on stream in Canada and our engineering department is quite busy, so that’s always a good sign, but no one can predict what’s going to happen. The industry is up and down, so we should never be surprised by a downturn. It’s the nature of our business.”
