Onaping Depth nickel-copper project is an underground mine extension being developed at Craig Mine, a part of Glencore’s Sudbury Integrated Nickel Operations (Sudbury INO) in Ontario, Canada. The project is located approximately 2,500m below the existing Craig mine.

Estimated to cost $700m, Onaping Depth will be one of the first mines in the world to be operated fully with battery electric-powered vehicles (EVs). The application of new clean technologies is expected to make it one of the most advanced and safest underground mines in the world.

Categorized into the Main and South East zones, the project has undergone extensive exploration programs between 1994 and 1999. A revised scoping study of the project was completed during 2012-2016, while a feasibility study was completed in 2016.

Approvals for the project were received in December 2017. The project is currently under construction and is expected to commence operations between 2023 and 2024. High-grade nickel ore from the mine is expected to be produced until 2035.

Annual production from the project is anticipated to be 20,000 tons (t) of nickel and 9,000t of copper.

Onaping Depth nickel-copper project location and geology

Onaping Depth nickel-copper mine is located in the Onaping-Levack region on the north-western portion of the Sudbury Igneous Complex (SIC). It is situated near the Fraser Mine and the Strathcona Mill.

The Sudbury structure is host to many Ni-Cu-PGE magmatic sulphide deposits, which are situated at the base of the SIC. Major minerals identified at the site include pyrrhotite, pentlandite, and chalcopyrite, which are hosted by contact sublayer, footwall breccia, quartz diorite, Sudbury Breccia, and a variety of footwall rocks.

The project will be accessed by a 1,430m-long internal shaft and will also be installed with underground infrastructure.


The Onaping Depth nickel-copper project is estimated to contain 14Mt of recoverable resources, grading 2.24% Ni and 1.01% Cu.

Benefits of digitalization of Onaping Depth

The Onaping Depth project will be equipped with digital technologies such as real-time remote management, monitoring, and control from surface. Innovative safety systems will be integrated into the operation in addition to mine-wide Wi-Fi communication between employees and from underground to surface.

The battery electric vehicles (EV) to be used at the project will be a more effective system to save energy compared to a diesel-fueled operation. The EVs are expected to minimize the power used for ventilation and refrigeration at the project.

The battery vehicles to be used are the R1700 XE, Caterpillar’s first commercial battery electric load-haul-dump (LHD) vehicle. The LHD is a result of the extensive research and testing conducted on the proof-of-concept R1300 at Sudbury INO underground operation.

The usage of electric-operated mobile fleet will eliminate the return air ventilation ramp, fresh air raise, ventilation fans, and ore passes.

New technology will be applied to critical ventilation and cooling systems, where the ambient rock temperature can reach 40°C at depth. The reduced size and number of ventilation openings is expected to save C$24m (approximately $17.8m) in addition to an estimated operating savings of C$8m (approximately $5.9m) per annum from reduced energy usage.

The energy savings will be approximately 44% from ventilation, while those from cooling equipment are expected to be 30%. The application of EVs is also expected to reduce greenhouse gas emissions by 44%.

Mining and processing

Underground mining with bottom-up mining approach supported by a single shaft development will be conducted at the Onaping Depth project.

The project will have a 7.2m diameter production shaft, which will be sunk from the 4025 Level of Craig Mine. The shaft will be approximately1.5km horizontal from the existing Craig shaft.

A fleet of 40t, 14t, and OEM 14T/18T LHD trucks will be used for underground mining operations at Onaping.

The ore mined at Onaping will be processed at the nearby Sudbury mill and smelter, while the existing infrastructure of Craig mine will be used as part of the project.

Contractors involved

Glencore has engaged Cementation for the design and construction of the new internal underground shaft for the Onaping Depth Project, in September 2018. The contractual scope includes the construction of hoistrooms, underground headframes for the shafts, and a 3m diameter raise bore as a pilot raise for the final shaft excavation.

Hatch provided a digital underground mine management solution, which is focused on reducing in-shift variability at the Onaping Depth nickel-copper project.