One of Alberta’s top watershed scientists says he doubts the massive coal sediment spill in the Athabasca River will be distinguishable from the toxins already polluting the watershed, but should serve as a wake-up call for those downstream of oilsands tailings ponds.
Dr. David Schindler of the University of Alberta, whose career has been spent researching contaminants linked to industry in the Athabasca oilsands region, said while he believes the Alberta government is correct in asserting the 1 billion-litre spill from the Obed Mountain coal mine likely holds “no immediate risk” to human health, future tailings pond breaches most certainly could.
“This spill should be wake-up call,” he told The Journal. “Similar dykes are holding back tailings ponds in the oilsands that are much larger and much more toxic. Dyke breaches are unusual, but they can be disastrous. It is time we did something about this huge threat.”
Without having the total volume released for each contaminant, Schindler said his suspicions about the recent spill are guesses, but said most of the sediments will likely be deposited in the Peace-Athabasca Delta around Fort Chipewyan before slowly dispersing farther upstream, “moving a bit each year.”
Though it’s too early to tell long-term effects, he said he doubts this spill will be distinguishable from existing contaminants in the river from other upstream development.
“I doubt whether it will be possible to tell any effects there, but it might be possible that some of the mercury and other contaminants will add to the burdens of fish that are already too high,” he said. “Past data are not very good, and my guess is that it will be impossible to distinguish this spill from the total.”
Determining the effects on human health based on consumption of fish and other wildlife in the delta, he noted, will take much more time.
“If there is enough mercury to further elevate concentrations in fish, it will take months to move into the food chain. It must be methylated first, a bacterial process that is more rapid in warm weather. We will not be able to know this until next year, and then only if there is comprehensive sampling,” he said. “I am hoping that it is not significant.”
Preliminary results released by Alberta Environment and Sustainable Resource Development (ESRD) on Tuesday showed most of the contaminants from the spill are contained in particles that are settling out along the river bed as the 150-km plume travels downstream.
Those contaminants include metals like mercury, lead and zinc, along with several cancer-causing polycyclic aromatic hydrocarbons (PAHs), many of which when sampled from within the plume presented at levels exceeding guidelines for drinking water and protection of aquatic life.
While Schindler said he suspects there will be some movement of contaminants downstream again at spring freshet, those will mostly slide along the river bottom and do not pose “great cause for concern.”
Water treatment facilities also filter out particles, he said, adding that Fort Smith should not be concerned.
“I think (Alberta Health is) correct that there are no human concerns from drinking water once the muddy cloud has passed. I doubt whether the spill will even be detectable in the Slave River,” he said.
The territorial government said on Tuesday that it was continuing to track the coal spill as it makes its way closer to the NWT.
“Currently, there is no cause for concern about the spill in the Northwest Territories,” Environment and Natural Resources (ENR) Minister Michael Miltenberger said in a press release. “We are continuing to track the spill and are making preparations for monitoring in the NWT should, or when, the plume moves into the Slave River.”
The plume is expected to arrive at Lake Athabasca around Dec. 4. Though it was originally estimated to reach the NWT between Dec. 7 and 10, it appears to be slowing down. ENR reported on Wednesday afternoon that it is now traveling at an average speed of 1.3 km/hr down from the previous average of 5 km/hr.
As of Wednesday, the leading edge of the plume was at Grande Rapids, about 114 km upstream of Fort McMurray.
The GNWT and Aboriginal Affairs and Northern Development Canada (AANDC) are working with the Town of Fort Smith to place monitoring equipment and collect water quality samples from the Town’s fresh water intake during the period before and after water exposed to the plume flows through the Slave River, said ENR’s spokesperson Judy Mclinton.
According to ENR, dilution is expected to mitigate some of the concerns by the time the spill reaches the Slave River.
“The majority of water in the Slave River comes from the Peace River. The Slave River has a mean annual flow rate in excess of 4,000 cubic metres per second so further dilution of the plume is expected,” stated the release.
Alberta issued an environmental protection order on Tuesday demanding Sherritt International carry out a number of remediation and monitoring efforts, mostly centered on the Plante and Apetowun Creeks, which sustained the immediate dump from the tailings pond when the dyke breached on the evening of Oct. 31 near Hinton, Alta.
A news release issued by Sherritt on Tuesday evening said the company is working closely with regulators to restore affected areas and is following the movement of the sediment past downstream communities, where it is carrying out daily water quality monitoring.
“We are deeply concerned about what’s happened here and we are committed to making this right,” said Sean McCaughan, Sherritt’s senior vice president, coal. “We began our testing the morning after this happened and, to date, these samples have indicated that the sediment travelling downstream in the Athabasca River poses no risk to human health or safety.”