Our strategy to reclaim tailings combines the innovation of new technologies with the search for emerging solutions through collaboration with industry, academia and the broader scientific community.
First full-year operation
of $1.9 billion tailings centrifuge plant.
Construction of 85-hectare area on
reclaimed tailings underway.
Over 5 million cubic metres
of soil material produced from centrifuge plant.
Through the use of tailings ponds, we maintain a highly efficient water recycling process which reduces water withdrawal from the Athabasca River. In fact, approximately 15 per cent of our water needs are met through this river system. However, the storage of tailings also creates a potential long-term liability because of the volume that must be managed responsibly and cost-effectively before reclamation can occur.
Tailings management is a priority across the organization. Our strategy to reclaim tailings currently incorporates three technologies – centrifuged tails, composite tailings (CT) and water capping – while actively working with industry partners, academia and the scientific community towards developing further solutions. We are committed to meeting government regulation and the expectations of all Albertans towards responsibly managing this environmental challenge.
To learn more about tailings and how they are stored, click here.
Syncrude is a member of the Mining Association of Canada (MAC) and participates in the Towards Sustainable Mining (TSM) initiative which outlines best practices in areas such as tailings dam safety and operation. Internal assessments are required annually, with an independent verification every three years. Results from the 2016 performance verification confirm that we have a well-developed tailings management system, with comprehensive monitoring and external technical review practices. Further information on the MAC tailings management protocol can be found on their website.
To reclaim tailings, we’ve so far invested approximately $3 billion in three main technologies:
In 2016, we had our first full year of production from the $1.9-billion tailings centrifuge plant. This plant accelerates the reclamation process by centrifuging fluid fine tailings (FFT) to create a clay soil material that can be used in landform restoration construction. The technology involves putting tailings through equipment where a spinning action, or centrifuging, separates out the water. Released water is recycled back into plant operations. The resulting clay material will initially be used to reclaim portions of our North Mine, where it will be capped with soil and re-vegetated. In 2016, 5.29 million m3 of material was produced from 5.97 million m3 of FFT.
Composite Tailings (CT) technology combines FFT with gypsum and sand to create a mixture that is deposited in mined-out areas where the tailings release water and quickly settle. The area can then be capped with sand and soil, enabling the development of landscapes that support forests and wetlands. CT is being used at both the Mildred Lake and Aurora North sites.
CT placement in the East Mine began in 2000 and was complete in 2011. Sand capping to establish closure drainage is ongoing, and the entire area is expected to be fully reclaimed by 2022. The 54-hectare Sandhill Fen wetland research project was constructed at the northwest end of this area. We are also reclaiming an adjacent 85-hectare area (called the Kingfisher). More information on these reclamation projects can be found in the Land chapter.
One of our most extensively researched tailings management techniques is the capping of FFT with water to form a lake environment. Syncrude’s research and testing dates back to the 1980s, and culminated with the commissioning of the industry's first commercial-scale demonstration in late 2012 in our former West Mine pit.
A comprehensive research and monitoring program is underway to study the performance of the lake as it evolves into an aquatic ecosystem. Research and monitoring focuses on water quality, impacts of the underlying FFT layer, performance of the littoral (shallow shoreline) zone, interaction of biological communities, consolidation of the tailings, development of the shoreline, and the establishment of plants and insects.
Monitoring since 2013 indicates good progress on key performance factors such as shoreline stability, consolidation and stability of the underlying fluid tailings layer, improving water chemistry and decreasing naphthenic acids. We have noted the presence of hydrocarbon on the water surface and shore, and are investigating options for skimming and shoreline cleaning. Waterfowl deterrents continue to be in place throughout this period.
We are currently researching additional technologies that could be used to supplement existing tailings remediation methods. These include:
Commonly known as rim ditching, accelerated dewatering is based on methods successfully used in the Florida phosphate industry. This technology mixes FFT with an organic compound called flocculant, which is then placed in deep deposits. The flocculant is the same material used by municipal water treatment systems. Flocculant molecules wrap around the clay mineral particles in the FFT, forcing them to settle faster. Initial tests have shown a reduction in FFT volume by 50 per cent in three to five years. If tests continue to be successful, accelerated dewatering could be an energy- and cost-efficient enhancement to our tailings reclamation activities.
This method, studied since the late 1980s, mixes FFT with overburden to create a fully functional surface that can be walked or driven upon. A demonstration pilot plant operated in 2014 and 2015, with commercial deployment in 2016. Deposit monitoring continues and results so far support the use of this technology for the combination of FFT treatment and landform construction.
We operate one of the largest private sector research facilities in Western Canada and participate in Canada’s Oil Sands Innovation Alliance (COSIA), which exchanges findings among industry operators. COSIA is currently coordinating over 75 active tailings management projects with its members. Further information is available by downloading a PDF (6MB) of the COSIA 2016 Project Portfolio.
| 2012 | 2013 | 2014 | 2015 | 2016 | |
|---|---|---|---|---|---|
| Fluid Tailings volumes (million m3) | - | - | 469.6 | 476.3 | 501.2 |
| Annual tailings reclaimed1 – centrifuge (million m3) | - | - | 2.5 | 3.5 | 5.3 |
| Annual tailings reclaimed2 – composite tailings (million m3) | - | - | 12.1 | 11.0 | 1.1 |
| 2012 | 2013 | 2014 | 2015 | 2016 | |
|---|---|---|---|---|---|
| Fluid Tailings volumes (million m3) | - | - | 113.0 | 127.9 | 131.2 |
| Annual tailings reclaimed2 – composite tailings (million m3) | - | - | 13.2 | 21.7 | 25.1 |
1 Volume of treated tailings (cake) produced calculated using a combination of instrumentation and sampling data.
2 Volume of treated tailings (composite tailings beach deposit) produced calculated assuming a dry density of 1.45 tonnes/m3.
Note: Performance metrics have been modified from that previously reported to better align and ensure consistency with submissions to the Alberta Energy Regulator as of the 2014 reporting year.