Design of tailings management facility for Teck QB2 project

WSP* personnel from six countries contributed to the design of the tailings management facility (TMF) for Teck’s Quebrada Blanca Phase 2 Project. QB2’s operation incorporates extensive environmental measures including the use of desalinated seawater and a tailings management plan that maximizes water recovery in challenging terrain.

This challenging task required several in-depth designs and various analyses to design a facility capable of handling 140,000 tonnes of tailings per day that will be transported by gravity to the TMF, where the tailings will be separated into fine and coarse fractions. The coarse sand fraction will be used for construction of the storage embankment, while the finer fraction will be deposited into the tailings impoundment.

“Responsible management of mine tailings is an important part of our business,” explains Paul Bedell, Engineering Manager. “Having the opportunity to work on a high-profile project like this and leverage our best practices from various disciplines to design this facility is a true honour. The entire team takes this responsibility very seriously, and we are all proud of what has been accomplished: a sound tailings management facility design, aligned with the industry imperative of ensuring safety. This was the result of collaboration with our clients and across our internal international teams, work environments, and languages.”

The design

In addition to facility embankment design, services included: surface water management design, tailings material classification (i.e., cyclone station) design, and pipeline design for water and tailings distribution with electrical, structural, and instrumentation components.

The TMF will be developed starting with a 35 m high rockfill cofferdam, 120 m high rockfill starter dam, and then the tailings sand embankment will be raised throughout the life of operations. At the end of the 25-year mine life, the tailings facility will be 310 m high. The use of cyclone sand is a common practice in Chile and has proven to be a safe method of construction for large scale structures such as required for this site.

Water is added to reduce the solids contents of the tailings for cycloning to produce sand for the dam construction and deposition into the TMF. The complex deposition system and tailings management maximize the reclaimed water.

Location

Chile

Client

Teck

Height of rockfill cofferdam

35 m

Initial mine life (years)

28

Tonnes of tailings per day

140,000

Project and client management

The lifecycle of the project (pre-feasibility through to construction) was carried out over five years. More than 400 personnel from WSP* contributed to the project, from six different countries and much of the work was in two different languages – a great example of collaboration across cultures and work environments. With any project of this duration and complexity, there were changes to personnel, and throughout the project stages, a concise and direct channel of communication was required with the client and stakeholders. Client expectations were recorded during the project kick-off and robustly tested throughout. It was imperative that the roles of responsibilities of key personnel, such as the Project Manager, Engineering Manager and Technical Leads, were clearly defined and that the team continued to evolve over the project life.

What’s next?

Our ongoing work on the QB2 project is in the capacity of construction quality assurance (CQA). Construction is expected to take approximately three years, with the mine operations currently planned to be underway in 2022.

For more information, please visit the QB2 public website for photos and general information about the project.
For more information about our involvement, please contact Paul Bedell (Engineering Manager) or Jason Doyle (Project Manager).

*This work was conducted by Golder professionals who joined WSP in an acquisition completed in 2021.