Calgary scientists have recently uncovered in the Northwest Territories what they believe to be some of the most acidic natural water globally. This phenomenon is a result of climate change triggering the thawing of permafrost and the erosion process known as slumping from the Smoking Hills Formation, causing the leakage of toxic metals and a highly acidic solution into the surrounding rivers, bays, and potentially the Arctic Ocean.
Stephen Grasby, a research scientist with the Geological Survey of Canada, visited the site on the territory’s north shore in both 2017 and 2023. He was astounded by the immense levels of toxicity and acidity present in the ponds surrounding the Smoking Hills. Grasby expressed his awe at witnessing nature’s ability to produce some of the most toxic acidic waters ever encountered, surpassing what humans could create at an industrial site.
The toxic metals contributing to this natural occurrence were initially trapped in iron sulfide minerals, commonly known as pyrite or “fool’s gold,” buried underground around 85 million years ago during a period of intense volcanic activity in Arctic Canada. These metals are released when the pyrite comes into contact with oxygen. Previously shielded by a layer of rock and permafrost, the exposure of pyrite to oxygen has increased steadily due to slumping, resulting in the release of significant amounts of metals into the water bodies surrounding the Smoking Hills.
Grasby noted a remarkable transformation in the landscape between his two visits, with an escalation in the number of slumps occurring. The ponds appeared black and viscous, resembling oil more than water, with such high acidity that measuring the pH level accurately posed a challenge for the research team.
The ground surrounding the water exhibited extreme temperatures, surpassing the capacity of their equipment to measure accurately. Evidence of melted rock suggested temperatures exceeding 1,200 degrees Celsius just beneath the surface layer, creating a unique phenomenon known as paralava. This hot rock layer beneath the surface led to a peculiar effect where walking on the ground revealed the scorching layer beneath.
The ongoing thawing of permafrost, driven by climate change, exacerbates the situation further. While permafrost thawing is not a new phenomenon, its repercussions are only beginning to be comprehensively studied. This thaw has manifested in a new outcome impacting water quality, as highlighted by Elliott Skierszkan from Carleton University, who is at the forefront of studying geogenic contaminants in groundwater.
The potential environmental consequences of the Smoking Hills formation remain largely unexplored, raising concerns about metal leakage into other bodies of water. Grasby and Skierszkan emphasize the need for additional research to deepen the understanding of the Smoking Hills and the impact of climate change on this unique ecosystem.
They stress the importance of these findings for the local communities and advocate for further research to comprehend the implications of these accelerating processes on the pristine Arctic environment.
