Suncor Energy Receives Conditional Regulatory Approval for Oil Sands Tailings Management Plan; Projected 30% Reduction in Volume
|Schematic of Tailings Reduction Operations (TRO). Click to enlarge.|
Suncor Energy has received conditional approval for its oil sands fluid tailings management plan from Alberta’s Energy Resources Conservation Board (ERCB). The plan proposed the expansion of a new approach to tailings management called TRO (Tailings Reduction Operations), which involves converting fluid tailings into a solid landscape suitable for reclamation. The project is located 40 km northwest of Fort McMurray.
Tailings are a mixture of fine clay, sands, water and residual bitumen produced through the oil sands extraction process, and are held in massive “ponds”. As tailings settle, a portion will eventually form mature fine tailings (MFT), a substance that has historically taken many decades to firm up sufficiently for reclamation.
A December 2008 report published by Environmental Defence concluded that oil sands tailing ponds are leaking more than 11 million liters of contaminated tailings water per day—more than four billion liters (1.056 billion gallons US) per year—into the groundwater in Canada. (Earlier post.)
Tailings ponds contain toxic contaminants such as heavy metals, polycyclic aromatic hydrocarbons (PAHs) and naphthenic acids. Naphthenic acids in particular break down very slowly and therefore pose a long-term threat to the groundwater of the region.
According to ERCB, tailings ponds arising from oil sands surface mining operations currently cover an area of more than 130 M square meters with some 720 M cubic metres of fine tailings (FT) collected. ERCB recently issued Directive 074 which requires oil sands operators to reduce the amount of FT going into liquid tailings by 50% by 2013 and to turn captured FT into stackable deposits ready for reclamation five years after deposits have ceased.
During the Suncor TRO process, MFT is mixed with a polymer flocculent and then deposited in thin layers over sand beaches with shallow slopes. This drying process occurs over a matter of weeks, allowing more rapid reclamation activities to occur. The resulting product is a dry material that can be reclaimed in place or moved to another location for contouring and replanting with native vegetation, according to the company.
The ERCB believes that application of TRO will enable Suncor to reduce the volume of fluid tailings remaining at the end of the project life by 33 million cubic meters (about 30%). Suncor’s plan does not include the creation of any new tailings ponds and will allow Suncor to operate five fewer tailings ponds and use less space for fluid tailings storage than originally applied for.
TRO will require Suncor to continue utilizing four of its existing tailings ponds. Those tailings ponds are scheduled to be decommissioned in 2017, 2029, 2032, and 2035.
Suncor has been researching, developing and testing the TRO technology since 2003. The company will rapidly accelerate the implementation of this technology across its existing operations.
We expect to invest more than $1 billion to implement our new TRO technology, potentially reducing tailings reclamation time by decades.
—Kirk Bailey, executive vice president, Oil Sands
Suncor has already committed approximately $450 million to TRO technology and other measures designed to improve tailings management and meet Directive 074 requirements, according to the ERCB. Thus far, oil sands operators have committed more than $1 billion in upgrades to comply with Directive 074, the Board said.
Suncor’s plan is the third of those submitted by six oil sands operators in September 2009 to the ERCB. Tailings plans submitted by Albian Sands Energy Inc.; Canadian Natural Resources Limited; Imperial Oil Resources Ventures Limited; and Shell Canada Inc. are currently being reviewed by ERCB staff.
Suncor video on TRO