Flames arena complex might have to contend with contaminated soil

With the new Flames sporting complex to be announced today and speculation it will be built on the west side of downtown, there are questions about soil contamination on the site.

Until the '60s, the area just west of the Greyhound bus depot housed a creosote plant, and that toxic, oily substance used to preserve wood leached into the earth. 

It causes skin and lung problems and has been associated with certain cancers.

Larry Bentley, a University of Calgary geoscience professor, was a groundwater management advisor to the province when it partially remediated the site in the late '80s and early '90s.

He says there was approximately 4,750 cubic metres of creosote on the site at that time.

"To put that in perspective, that's about two Olympic swimming pools full of this oily, toxic substance," he said.

The province's efforts were more about containment than cleanup, 

"What they wanted to do was to keep creosote from entering the river and going below the river and having any more leave the site," said Bentley.

To that end, they built a containment wall but didn't remove the contaminated soil or leftover creosote. That means any construction will have to contend with the toxic waste.

"So basically you've got to excavate all that sand, clean it up and take all that toxic material somewhere else," said Bentley, adding any building will likely need vapour control systems to contend with the creosote left deep in the ground.

The work that was done almost 20 years ago estimated the cost of cleanup would be anywhere between $40 and $50 million, but Bentley says the cost today could be as high as $300 million.

There is still no word on who will cover the cost of remediation on the site, or the cost of financing a new sporting complex.