The coke oven gases being released by ArcelorMittal Dofasco this week as it upgrades its plant contain a range of carcinogenic chemicals, warns a McMaster University professor.

The company advised community stakeholders Friday visible emissions might occur this week as it embarks on the next stage of its coke plant restoration project, but environmentalists say what was supposed to be intermittent has actually been constant.

“We understand the need to flare,” said Lynda Lukasik, Environment Hamilton’s Executive Director. “But this is constant. There’s a disconnect from what was described and what we’re seeing.”

'I think a lot of companies look at these fines as a cost of doing business.' - Jim Quinn, McMaster University professor

The emissions that can be seen this week as black smoke over the plant are happening because the company is replacing the pipes at one of its byproducts plants. As a result, the coke oven gas that is normally consumed at the byproducts plant is being flared through the two batteries at its No. 2 coke plant instead.

Coke oven gas is a “very complex mixture of chemicals,” McMaster University professor Jim Quinn told CBC Hamilton. The main family of chemicals found in that cloud is called Polycyclic Aromatic Hydrocarbons, or PAHs for short. PAHs, such as benzene, are compounds made up of carbon, and larger molecules are carcinogenic and linked to mutation in lab tests on rats.

Coke oven gas also contains some of the same components in tobacco smoke that have been linked to lung cancer, Quinn says. “This sort of pollution definitely has a local footprint,” he said. “Anyone downwind will be exposed to some of the contaminants.”

Representatives from ArcelorMittal Dofasco could not be immediately reached for comment Monday. Jim Stirling, the company's general manager of environment, told community stakeholders Friday that “all efforts will be made to minimize the environmental impact of the flare.”

The Ministry of the Environment is aware of the planned work, Stirling added.

Matters resolved

The steel company announced Friday these emissions would be seen this week – the same day that Environment Hamilton accused the Ministry of Environment of giving the company a free pass on pollution for the next five years as it undertakes an $87 million upgrade to its operation.

ArcelorMittal Dofasco was fined $390,000 in May after pleading guilty to a series of environmental charges for violating air quality standards.

“I think a lot of companies look at these fines as a cost of doing business,” Quinn told CBC Hamilton Monday.

Friday, Environment Hamilton revealed an email exchange with the ministry in which a spokesperson said they wouldn’t pursue further investigation into the coke plant during the upcoming five-year period in which the company has promised to fix the problems.

The spokesperson wrote, "the guilty plea resolves these matters."

However late Friday, in response to the accusation, the ministry it said it would monitor the company's progress and "would continue to investigate and prosecute where appropriate."

Guilty pleas

The pipework repair is part of the company's $87 million investment in major restoration at its No.2 and No.3 coke plants over the next five years. An order from the Ministry of the Environment compels the company to undertake much of the work and meet prescribed deadlines for key elements of it.

ArcelorMittal Dofasco's Hamilton facility has three coke plants, where coal is used to produce coke, a fuel for the facility's three blast furnaces. It is in the process to phase out its No.1 coke plant by March 2015. Shutting down the 56-year-old plants with three batteries and 105 ovens would result in permanent improvement in local air emissions, the company said.

The No.2 coke plant, commissioned in 1971, has two batteries and 106 ovens. The No.3 coke plant, commissioned in 1978, has one battery with 35 ovens.

The facility also houses three byproducts plants, which are responsible for the production of coke oven gas, tar, light oil and ammonia sulphate, as well as the removal of ammonia.

The Ministry of the Environment laid 13 charges against the company in March 2013 for air emission violations at its coke plants between April and August 2012. The ministry alleged that the company exceeded visible emissions (opacity) levels set by the province. 

The outcome came after more than a year of delay-plagued court proceedings. The company pleaded guilty to six out of 13 charges. The remaining seven charges were withdrawn.