TORONTO - Mining giant Vale Ltd. is moving ahead with a $2-billion plan to reduce sulphur dioxide emissions at its smelter in Sudbury, where the company's so-called superstack has long been seen as a monument of industrial development and pollution.
The initiative, which the Brazilian-based company describes as the largest in the history of Ontario, and likely Canada, has a goal of slashing emissions at the smelter by 70 per cent over several years.
"This reduction is in addition to the 90 per cent reduction in sulphur dioxide emissions realized since 1970 and complements the ongoing success story that is the regreening of the Sudbury region," Vale said in making the announcement Thursday.
The project, which is scheduled to start construction in April, is designed to put emissions below government mandated levels which take effect in 2015.
The target is to cut the stack's emissions to 45 kilotonnes per year, compared with the regulatory limit of 66 kilotonnes a year. Dust and metals emissions are also expected to be reduced by 35 to 40 per cent.
"It is important that we put in the infrastructure to ensure the sustainability of Sudbury and the community," said Vale project director Dave Stefanuto.
"We recognize that Sudbury has core assets and not only in terms of facilities but core assets in terms of people, resources and industry-leading expertise, so you know we really want to make sure that this investment is for the long haul."
"I think we are pretty confident that we are going to meet or exceed dust emissions as well," he added.
Vale has already spent about $100 million on the project over the past four years as it prepared for its final approval.
The company aims to wrap up construction by the end of 2015. It estimates that about 1,300 workers will be on site when the construction is at its peak, including about 100 from the Vale project team to oversee the project and another 100 working for the engineering consultants who have been hired.
The other 1,100 will be tradesmen — carpenters, boiler makers, mill wrights and labours — with the peak number on site in 2013.
"We plan on engaging as many of the local people (as possible) because they have experience within our facility already," Stefanuto said.
The high cost of the project, which won't alter the appearance of the 380-metre-tall superstack erected by the former Inco at a cost of just $25 million in 1972, is due to a number of factors.
Although the superstack will stay the way it is "there will be considerably less going up the stack," Stefanuto said of the expensive technology being employed.
However, the overall look of the smelter site itself which change markedly, with existing duct work for gas capture systems being replaced, along with construction of a new acid plant to convert gas into sulphuric acid along with a new facility to move materials handling indoors.
"So the scope of the project is very large to handle all these different aspects," Stefanuto said, adding that cost have escalated enormously over the years.
"We were emitting around two million kilotonnes of sulphur dioxide out of our facility a year" back when the superstack was constructed."Today we're at about 150,000, and after the clean air project we will be down to about 45,000 kilotonnes," he said, noting that each reduction is increasingly more difficult and more expensive to achieve.
Stefanuto said the company has been engaged in many regreening projects in the Sudbury area over the years and that scientists have been able to show "direct correlation with improvement in the recovery of freshwater lakes (in Northern Ontario) with the reduction in SO2 emissions over the years that our company has achieved."
The Sudbury site includes the former Inco Ltd., which it bought about five years ago in a wave of consolidation that led to the foreign takeovers of major Canadians miners such as Inco, Falconbridge and Alcan.
When it was constructed the superstack was the tallest chimney in Western Hemisphere, the tallest free-standing structure in Canada (since eclipsed by the CN Tower) and the second tallest freestanding chimney in the world after the GRES-2 Power Station in Kazakhstan.