2010 Major Reclamation Award:
Suncor Energy has made strong advances in tailings pond reclamation at their oil sands mine north of Fort McMurray, Alberta. In 2010 Suncor became the first oil sands company to conduct surface revegetation of a tailings pond. As well, since 2003, Suncor has been researching, piloting and commercializing a relatively new approach to tailings management called “Tailings Reduction Operations” (TRO™).
“Environmental sustainability is a core value at Suncor,” said Shelley Powell, the company’s Vice President of Extraction Operations, in accepting the award. “We absolutely believe in minimizing our environmental footprint by utilizing new technologies and innovations along the way.” She called it a success for the entire industry, and thanked the many people – employees, contractors and other stakeholders – who had contributed a great deal of time, energy, and brainpower to coming up with such an innovative, workable and, now, award-winning solution.
Tailings Pond 1 Consolidated Tailings (CT) Reclamation
“Pond 1,” a 220-hectare site located at Suncor’s oil sands mining operations north of Fort McMurray, was the company’s first storage pond for oil sands tailings when commercial production began in 1967. Pond 1 was in operation for 40 years before being decommissioned in December 2006 and turned over for reclamation the following month. The Consolidated Tailings process started with infilling the pond with 30 million tonnes of reclaimed tailings sand. The CT process involves a gypsum treatment, followed by adding a coke capping with a geo-synthetic membrane. Drainage systems and swales were then developed to manage water runoff from the pond. As these activities were completed, landscaping activities began, which involved placing 1.2 million cubic meters of topsoil over the surface, to a depth of 50 centimetres.
Over the next two decades, Suncor will maintain and closely monitor progress on the site, including the growth of 630,000 shrubs and trees planted in 2010. Ongoing soil, water, and vegetation assessments will help ensure the site is on course for return to a sustainable landscape and self-sustaining ecosystem.
“Tailings Reduction Operations” Process
The TRO™ process is a new approach Suncor has developed for managing tailings – left over material produced through the extraction process that separates bitumen from the oil sands. Suncor’s process is expected to speed up tailings reclamation and to reduce the volume and footprint of fluid tailings on the landscape. Suncor believes the process will help it meet new provincial regulatory requirements and the changing expectations of stakeholders. The company plans to invest more than $1 billion to implement its process, which it expects will reduce tailings reclamation time by up to two decades as compared to its current methods.
During the process, mature fine tailings are mixed with a polymer flocculent and then deposited in thin layers over sand banks 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 final reclamation.
The expected benefits of the process to manage tailings include:
- Reducing the need to build more tailings ponds as mature fine tailings will be consumed more quickly.
- Accelerating reclamation as the process allows progressive reclamation of mined areas.
- Reducing the inventory of mature fine tailings.
Suncor is in the process of deploying this technology across its existing operations. As the first tailings management process to achieve a trafficable surface capable of supporting revegetation, the process represents a significant step forward in solving the challenge of tailings pond reclamation.