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Perspectives: Tailings Ponds Reclamation in Oil Sand Mining

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Perspectives: Tailings ponds reclamation

Canadian Oil Sands

Northern Alberta and Saskatchewan’s oil sand reserves comprise 97% of Canada’s proven oil reserves, summing up to 170 billion barrels of recoverable bituminous oil. Bitumen is primarily made up of Polycyclic Aromatic Hydrocarbons (PAHs), sulfur, lead, mercury, and other heavy metals. Once the bitumen is separated from its ore, a large volume of tailings and contaminated water are released as byproducts
of the bitumen extraction process.​

Tailings Ponds: Inevitable Consequences

As a result of oil sand processing, tailings ponds contain the residual bitumen, leachate, and other dissolvable chemical compounds. Reclamation of the tailings ponds entails the removal of existing tailings ponds and the recovery of the lands to their states before the bitumen extraction. The effort to regulate and reclaim tailings ponds has been made by both the Albertan government and the leading companies in the industry. In 2011, Suncor Energy invested $1.2 billion in their tailings reduction operations aiming to shorten the reclamation time from an average of 40 to 7-10 years. Syncrude, another
leading company in oil sand production, utilized their composite tailings (CT) technologies to drain the water in ponds and the dry them into more readily reclaimable substrates. Additionally, in 2016, the Government of Alberta issued Directive 85, a guideline requiring the reclamation of fluids tailings within ten years of the closing of an oil sands mine.

Tailings Ponds Reclamation: Is it truly possible?

Regardless of all the effort to reduce and reclaim tailings ponds, there has been a persistent suspicion concerning the post-reclamation environmental impact of tailings ponds as well as the permanent environmental damage that it has on the nearby communities.

Environmental impacts

A primary concern with tailings ponds is the leakage of contaminants into the environment. The Environmental Defence report calculated 11 million liters of contaminated wastewater leakages despite prevention strategies such as interceptor ditches and wells. A study by the Joint Canada-Alberta Implementation Plan for Oil Sands Monitoring has released information regarding the release of PAHs into the environment. The study found that 1069 kg per year of PAHs are being released from tailings into the air in the whole of the Oil Sands Region (OSR) of Western Canada. PAHs are an organic compound of which are of particular importance in oil sand processes due to the health impacts that they impose when released into the environment. They have a low degree of acute toxicity to humans; however, their ultimate toxicity impact is cancer. Prior testing has proved increased cases of lung, skin and bladder cancers linked with their occupational exposure.

Impacts on communities

In 2014, a study conducted at the University of Manitoba was the first to draw links between the leakage of PAHs into water and air and the increasing cancer rates in aboriginal communities downstream the oil sands production. Chief Steve Courtoreille stated, “This report confirms what we have always suspected about the association between environmental contaminants from oil sands production upstream and
cancer and other serious illness in our community.” Overall, the study found high concentrations of PAHs and heavy metals in kidney and liver samples in moose, ducks, muskrats, and beavers harvested by community members. This, in turn, threatens the wildlife that makes up traditional food sources for the communities that inhabit the area, and their water supply, which is decreasing. 

Ultimate Question

Although several studies support the advantages associated with oil sands tailings ponds, there are nevertheless some very concerning environmental and societal impacts. Therefore, it is our responsibility to moderate oil sands production while keeping in mind the needs of our communities, and the impacts that the industry has on them. Furthering advancements in reclamation technology can help mitigate the
impacts, but it ultimately raises the question of whether or not fully ethical reclamation technologies can ever be achieved?

References

i. Speight, James G. Oil Sand Production Processes. Amsterdam, Netherlands: Elsevier/Gulf Professional Pub., 2013. Print.

ii. Alberta, Government. "About The Industry | Alberta Canada - Alberta, Canada".

iii. "EHP – Oil Sands Development: A Health Risk Worth Taking?". Ehp.Niehs.Nih.Gov, 2016, 

iv. The Government of Alberta, (2013). Oil Sands Tailings..