In quaint St. Marys, cement plant odour has the town talking

Complaints about noxious odours from the local cement plant are raising a stink in St. Marys, a quaint Ontario town known for its natural limestone deposits.

Residents worried about smelly emissions force townhall meeting with environment ministry officials

Residents say they began to notice a noxious smell from the St. Marys Cement plant in recent years, but the company says their processes haven't changed. (Andrew Lupton/CBC)

In search of a nice Ontario town to settle in and raise their four-year-old daughter, quaint St. Marys ticked every box for Summer Weiler and her husband. 

Postcard pretty, with affordable houses and good schools, Weiler said the town was a natural choice.

St. Marys resident Summer Weiler says the smell from the plant can be overwhelming, depending upon the wind direction. (Andrew Lupton/CBC)

The couple moved from Woodstock in June 2016 and began restoring a century-old home close to downtown. Weiler's parents also made the move to St. Marys, located 40 minutes north of London and about an hour west of Kitchener. 

Not long after making the move, Weiler caught a whiff of something while playing outside with her daughter. 

"I smelled this burning chemical smell in the backyard," she said. "It was really strong and I asked my husband about it. He said someone might be burning tires."

In the months that followed and with the smell becoming more frequent, Weiler began to connect with others in town who also noticed the odour. Their descriptions were fairly consistent: an acrid, chemical smell, like burning plastic.

The stench was worse when the wind blew from the southwest. The culprit was soon singled out as the kiln at St. Marys Cement, the massive plant located just west of downtown. 

Weiler began to press the plant and local officials for answers. She bought expensive air filters and became active on a local Facebook group where 180 members discuss the smell. 

"It's been extremely stressful because we moved here for a better, safe, Huck Finn kind of life," she said. "There's been times I've been downtown and there's people from Toronto or wherever and they're saying 'What's that smell?' I try to stay positive because we do love it here, it's one of the most quaint towns I've ever seen."

St. Marys Cement is now owned by Brazil-based Votorantim Cementos, one of the world's largest cement producers. (Andrew Lupton/CBC)

Looking out her front window, Weiler uses the Canada flag atop the stone water tower — a St. Marys landmark — as an early indicator before stepping outside. 

"If that flag is pointing toward me, I know I'm going to smell it," she said. 

The smelly side of 'Stonetown' 

Much of the town's undeniable charm — one that draws new arrivals and carloads of tourists every year — is the area's massive natural limestone deposits. Nicknamed Stonetown, St. Marys streets are lined with impressive structures built in the 1840s out of limestone blocks carved from nearby quarries.  

That same limestone also feeds the massive kiln at the cement plant, which employs about 80 people in the town of 7,200. The CN Tower, Maple Leaf Gardens and the Darlington Nuclear station were all built using St. Marys cement.  

Located just west of downtown St. Marys, the plant has been a fixture in the town for decades. (Andrew Lupton/CBC)

To make cement — the key component of concrete — limestone and other materials are heated to about 1,400 C in a massive kiln.

The St. Marys kiln is fuelled by a mix of coal, natural gas and petroleum coke. 

Mayor Al Strathdee said in the past complaints about the St. Marys plant were mainly about dust, not emissions or odours. He said odour complaints began to spike in recent years, leaving the town "caught in the middle" of increasingly concerned citizens, Ontario's environment ministry and a St Marys Cement, a company he said has been "a good corporate citizen."    

One of the town's signature stone structures, the flag atop the water tower on Queen Street is used by one local resident as an indicator of whether the smell from the plant will be noticeable. (Andrew Lupton/CBC)

​"We're very concerned about the citizens' well-being and the quality of life in the town," said Strathdee. "We're trying to do what we can to mitigate the smells, or work with our corporate partners to try and do better." 

"We want to try to advocate for our citizens first and foremost but we also have a long history with the cement plant. We want to work with the regulating authorities and find a solution."

In response to rising complaints about plant, the province's environment ministry has:

  • Installed a temporary air monitoring station  It was installed in the summer and it's expected some of the data will be released today, though officials caution that three months of data is likely not enough to say conclusively whether or not the plan contravenes emissions standards. 
  • Conducted mobile monitoring  A monitoring van was working in the town this week and the province is hoping to release its data soon.
  • Required the company to conduct stack testing. This is carried out by a qualified contractor hired by the company.
  • Required the company to create an odour abatement plan MOE officials say this is in the works. 
  • Required the company to form a community liaison group. The group's first met in mid-November.

Town officials have also arranged a special meeting for tonight (Monday, Dec. 4) at the town hall. Expected to attend is an MOE district manager, about a dozen citizens who've complained or expressed concerns about the plant and a representative of the Perth District Health Unit. 

What's causing the smell?

Although it started in 1840 as a small operation owned by a local family, St. Marys Cement was bought in 2001 by Brazil-based Votorantim Cimentos. Owners of dozens of plants, the company is among the world's biggest cement producers.  

Rueben Plaza, the company's environmental manager, insists the company has not changed its processes in recent years. 

To make cement, limestone is heated in large kilns like the one seen in the background of this photo. Cement from St. Marys has been used over the years to build everything from the CN Tower to the Darlington nuclear plant. (Andrew Lupton/CBC)

"We're using the same fuels, the same limestone," he said in a phone interview from Mexico. "It's something we're trying to work out. There's no significant changes that would explain that kind of change in the odour or emissions."

Plaza, who has visited the St. Marys plant, said that to his nose, the smell is more typical of combustion gases, not burning plastic. But he admited the consistent smell descriptions from complaints are a problem.

"We are working with consultants to find a solution," he said. "It's a complex problem."

He insists the plant is complying with MOE's emission rules and said: "I don't have any health concerns about the plant."

Residents skeptical

Not everyone in town is convinced St. Marys Cement and the province is doing enough to solve the smell problem. 

Adam Maruscak is a surgeon who works in nearby Stratford. His wife commutes to London, making St. Marys an ideal spot to move and start a family. 

They bought a fixer-upper northwest of town and moved in early 2016.  

Maruscak said the smell has forced him to stop playing golf mid-round and put a sudden stop to yard work.

In a letter to Strathdee shared with CBC News, Maruscak is worried about what's causing the noxious smell.

St. Marys Mayor Al Strathdee says odour complaints about the plant have spiked in recent years, leaving the municipality to try and broker a solution between the citizens, the environment ministry and a company he says has been 'a good corporate citizen.' (Andrew Lupton/CBC)

"We now find ourselves considering to move both our residence and occupations to find a healthier environment in which to live and potentially raise children," he writes. "The toxic emissions produced by St Marys Cement factory have made it impossible for my family to continue to thrive here."

Strathdee, in response to Maruscak's letter, outlines the town's efforts to find a solution. 

"We currently have no evidence to back up claims of unhealthy conditions," Strathdee writes.

Weiler shares Maruscak's health concerns. Like him, she said her family may have to move if there's no solution to the smell problem. 

"We do love it here, but if it doesn't get better we're going to move to the outskirts of town," she said.

She plans to join about a dozen other St. Marys citizens looking for answers at tonight's meeting. 

About the Author

Andrew Lupton


Andrew Lupton is a B.C.-born journalist, father of two and a north London resident with a passion for politics, photography and baseball.


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