2016 INDUSTRY REPORT
With its $3-billion expansion nearing completion, PotashCorp’s Rocanville potash mine will rank among the largest underground mines in the world.
It’s been years in the making, but PotashCorp has nearly completed the $3 billion expansion of its Rocanville potash mine.
The final phase of the project, which began in 2008, is scheduled to be completed by the end of November. The expansion will double the mine’s operating capability, increasing it from 2.7 million tonnes in 2015 to 5.7 million tonnes when it’s ramped up in 2017. The new capacity will make it one of the biggest underground mines – potash or otherwise – in the world.
“At PotashCorp, all of our projects are world class, but the complexity of renovations taking place at Rocanville required a very high level of skill,” said Larry Long, general manager of the mine, located about 230 kilometres east of Regina near the Manitoba border. “Everyone involved in this project, from our contractors to the staff at Rocanville, deserves a lot of credit for their perseverance.”
Long said that sense of determination was especially needed during construction of the 1,123-metre service shaft at Scissors Creek, located 16 kilometres west of the main mine site. The shaft will move workers and equipment underground to mine a new area of the Rocanville potash deposit.
Excavation for the shaft began in 2010 and it took workers until June 2015 to reach the underground mine workings. One of the challenges to overcome while sinking the shaft was the Blairmore Formation, a water-bearing feature in the geology that overlays all Saskatchewan potash mines. To successfully sink a mine shaft through the Blairmore, the water present must be frozen to stop it from flowing into the shaft.
“There were a lot of technical hurdles,” Long said. “Shaft sinking is something that doesn’t happen all the time and there are not a lot of people with that expertise, so that was the single biggest challenge.”
Prior to Scissors Creek, it had been more than 35 years since a new potash shaft was sunk in Saskatchewan; the last one was a service shaft in Lanigan in 1979. Despite the challenges, Long said the increased capacity provided by the new shaft certainly justifies the hard work. The old service shaft was converted to a second production shaft to bring ore above ground.
“Potash mines are limited by the amount of ore they can get to the surface, but these shafts will essentially double our capability,” Long said.
The Rocanville expansion also includes a 500,000-tonne storage facility and a new mill. Long explained that the mine will operate using two mills: the original one at 1,100 tonnes per hour and the new one at 1,300 tonnes per hour once it’s fully commissioned.
The expansions have also increased employment at the mine. During peak construction periods, PotashCorp had more than 1,000 contractors on the site. Long said it was great to make a positive impact on the province’s economy, through the jobs created during the expansion and those needed to staff the larger mine.
“We more than doubled the workforce, so there’s an ongoing benefit from those salaries,” he said. “Our staff count has grown to nearly 800 people, compared to 325 when we started. The other ongoing economic benefits are obviously the services and supplies that we’ll need in the decades to come because of the increase in the size of the mine.”
As the expansion nears completion, Long said the focus is now on finishing the commissioning process.
“We have the skips and hoisting system that moves the rock from underground to surface, and underground you have the bins and loadout system that actually delivers that rock to the skips. The technical part is getting those two systems communicating with each other.
“We have to make sure the timing is as close as possible, so the material goes as fast and as efficiently as possible.”
PotashCorp has been willing to spend time and resources on the Rocanville expansion because the ore body is very favourable for low cost and efficient mining, Long said.
“I think people look at the potash ore bodies as being fairly homogenous, but actually they’re not,” he said. “There are variations in the deposits. At Rocanville, you’re going to invest a lot of money in the operations and in the end we will be able to produce significant amounts of potash at a low cost.”
Prior to Scissors Creek, it had been more than 35 years since a new potash shaft was sunk in Saskatchewan.