North Bay, Ont., and DND move to remediate 'forever chemicals' site that contaminated drinking water
The City of North Bay, Ont. and the Department of Na‐ tional Defence (DND) are set to begin a $20-million project this spring to reme‐ diate a site contaminated with perfluoroalkyl and polyfluoroalkyl substances (PFAS) - often referred to as "forever chemicals."
From the early 1970s to mid-1990s, DND conducted training exercises at the city's Jack Garland Airport with aqueous film-forming foams that contain PFAS. The foams seeped into the groundwater and contaminated wells and Trout Lake, the source of the municipality's drinking water.
"These activities were con‐ ducted according to the ac‐ cepted practices and regula‐ tions of the time," DND spokesperson Kened Sadiku said in an email to CBC News.
PFAS are a family of some 14,000 different substances that are characterized by a stable carbon-fluorine bond. That strong bond means it takes a long time for them to break down in the environ‐ ment.
Because they don't de‐ grade easily, PFAS are used in everything from paper pack‐ aging for food, to dental floss, glass cleaner, carpet‐ ing, guitar strings and a wide variety of other products.
The vast majority of these chemicals have not been tested for toxicity. - Miriam Diamond, University of
Toronto
Researchers are just be‐ ginning to understand some of the negative health effects linked to exposure to PFAS.
Miriam Diamond is a pro‐ fessor with the University of Toronto's School of the Envi‐ ronment who studies PFAS.
"The vast majority of these chemicals have not been tested for toxicity," she said. "For the few that have, there are definite concerns about toxicity."
They include links to liver and prostate cancer, preg‐ nancy-induced hypertension, fatty liver disease and affect‐ ing lipid function, which is linked to Type 2 diabetes.
Since 2013, Ontario's Min‐ istry of the Environment, Conservation and Parks has been measuring levels of 11 different PFAS chemicals in Trout Lake, where thousands of people in North Bay get their drinking water.
Last year, the average measurement of those 11 substances was 56 nanograms per litre. One nanogram is one billionth of a gram.
The Ministry of the Envi‐ ronment's interim advice val‐ ue, or recommendation, for PFAS in drinking water is 70 nanograms per litre. Those values are based on a guideline from Health Cana‐ da.
But Diamond said the PFAS levels in Trout Lake still concern her.
"They may be lower than the Health Canada guideline, but the Health Canada guideline doesn't reflect the latest evidence," she said.
Health Canada is currently working with the provinces, territories and other federal departments to propose a new objective of 30 nanograms per litre for the total sum of all PFAS mea‐ sured in drinking water.
If that passes, North Bay's levels would be nearly dou‐ ble Health Canada's recom‐ mendations.
The U.S. Environmental Protection Agency (EPA) is proposing an even stricter guideline of eight nanograms per litre for one particular type of PFAS called per fluo‐ rooctane sulfonic acid (PFOS).
PFOS levels in Trout Lake last year averaged 29 nanograms per litre, or seven times the limit being pro‐ posed by the EPA.
The Ministry of the Envi‐ ronment has measured much higher concentrations of PFAS in parts of Lees Creek, which runs from the North Bay airport to Trout
Lake. The ministry has mea‐ sured up to 772,160 nanograms of PFAS per litre in some naturally occurring foams in the creek.
The creek has had a fish‐ ing ban for several years be‐ cause of those high concen‐ trations.
DND's own testing near the airport, which started in 2017, found two wells had PFAS concentration levels above Health Canada's rec‐ ommendations. Those wells supplied water for five homes.
As of October, DND has tested PFAS levels at 163 properties near the airport. Twenty-two of those proper‐ ties have received an alterna‐ tive water supply due to high concentrations.
Remediation plans
The new remediation plans are expected to ad‐ dress contamination at the former firefighter training site at the airport.
DND and the City of North Bay have hired engineering firm Jacobs Consultancy Canada to lead the $20-mil‐ lion project.
"What we'll be doing this coming year at the firefighter training area is excavating some soil and actually send‐ ing it off site to a facility in Ontario that does soil recy‐ cling," said Carol Mowder, a chemical engineer and Jacob‐ s's senior technical consul‐ tant for the work in North
Bay.
"They'll be cleaning the soil up and removing the PFAS."
Mowder said they'll also explore ways to filter conta‐ minated groundwater at the site.
"So one option that we are considering would be to put in activated carbon into the ground," said her col‐ league, Travis Tan, Jacobs's project manager for the North Bay remediation.
"It's kind of like a Brita fil‐ ter that will filter the PFAS be‐ fore the groundwater leaves the site."
But a North Bay environ‐ mentalist is concerned the remediation won't address
PFAS that already entered lo‐ cal waterways over several decades.
"I did not get the read from the city's announce‐ ment of limited remediation options for the airport prop‐ erties that those other areas of contamination were going to be addressed," said Bren‐ nain Lloyd, the project co-or‐ dinator with Northwatch, an environmental advocacy group based in North Bay.
Karin Pratte, the city's lead on the remediation project, said there could be future phases to the project to address downstream cont‐ amination.
"The results of the impact of this first phase on down‐ stream will be determined through ongoing monitor‐ ing," Pratte said.
"And depending on the re‐ sults of this first phase and the success of the first phase, then yes, there may be future phases."
But future phases would require more funding, she added.
DND will cover 97 per cent of the cost for the current re‐ mediation plans.