Going Natural: Applying Innovative Solutions to Improve Water Quality
Teck’s research into water quality management has reached a major breakthrough with the successful development of an in-situ method to remove selenium and nitrate from mine-impacted water. The Saturated Rock Fill (SRF) facility built at Teck’s Elkview Operations can treat up to 10 million liters per day using naturally-occurring biological processes.
How it works
Mining steelmaking coal generates waste rock that is stored in large dumps. Precipitation travels through these waste rock dumps, picking up substances like selenium and nitrate along the way. Once water leaves the dump, it is carried throughout the watershed, which can have adverse effects on water quality in high enough concentrations.
In 2017, Teck built a SRF facility on a previously mined pit that had been back filled with rock and flooded with water. Inside this saturated area, naturally-occurring biological processes were enhanced with the addition of nutrients (mostly methanol and phosphoric acid) to increase the rate and amount of selenium and nitrate removal. Teck’s first SRF facility is now achieving near-complete removal of selenium and nitrate in 10 million litres of mine-affected water per day.
A game-changer for water treatment
The Elkview facility is a game-changer when it comes to how the industry will treat water in the future. At a total cost of $41 million, it is significantly less expensive and easier to construct than traditional active water treatment facilities. SRFs have the potential to augment or replace traditional active water treatment technology at approximately one-fourth the capital cost and half the ongoing operating cost.
“This project is at the forefront of managing water quality in mining,” says Dean Runzer, General Manager, Water Quality Management. “We’re continuing with our research to better understand the capabilities and limitations of this technology and how it can complement our approach to water management company-wide.”
Where to next
In addition to the SRF project, Teck currently has 20 R&D projects underway related to water quality in the Elk Valley, including projects to better control release of water quality constituents at source and to develop new water treatment methods.