Optimising water management
To produce 1 barrel of oil from the Athabasca oil sands requires, on average :
- 2 to 4 barrels of water in the case of mining projects.
- 0.5 barrels of water in the case of SAGD projects.
SAGD processes use saline or brackish water from aquifers. Open-pit mining makes use of freshwater from watercourses near the projects. In both cases, the water is recycled in the process.
We have designed our projects to optimize the water consumption, 3.1 barrels of water per barrel of oil produced at Joslyn and 0.3 barrels of water per barrel produced at Surmont, under optimal operating conditions.
Up to 80% of water needs for extraction and utilities will be covered by recycled water; only 20% by river water and collection from run-off. The mine will also be designed to have off-stream freshwater storage with a capacity of 90 days’ storage, which is the largest in the region, reducing dependency on Athabasca River water during low flow conditions in winter.
At the in situ Surmont project, water used in the steam-assisted extraction process is also recycled. For Surmont Phase 2, recycled water will cover over 90% of the volumes required for the process, and intake water will thus be limited to less than 10%. We are working towards reducing that amount with a solvent-steam co-injection pilot project that may further reduce the amount of steam required in the SAGD process, therefore reducing required water volumes.
Focus on regulation
Specific regulations apply to conserve Alberta’s water resources and encourage water recycling :
- For oil sands mining projects, water withdrawals from the Athabasca River are limited. In consideration of seasonal flow rates, authorized withdrawals in winter are half as high as in summer.
- For in situ projects, the use of freshwater and brackish/saline water is limited (either 10% freshwater + 15% brackish water, or 25% brackish water), and from the regulatory trend, it is expected that eventually no freshwater use will be authorized.
- No water – even treated – is allowed to be released from bitumen extraction processes.
- Checking through the water quality by both federal and provincial authorities