Anglo American signals design changes at Woodsmith polyhalite project

Anglo American has outlined plans to change elements of the design at its Woodsmith polyhalite project in the UK, which will have a bearing on both the sinking of the two main shafts and development of the underground mining area at the project.

The company has been running a detailed technical review on Woodsmith since mid-2020 to ensure the technical and commercial integrity of the full scope of its design. This followed the acquisition of the asset as part of a takeover of Sirius Minerals earlier that year.

“Now largely complete, the review has confirmed the findings of Anglo American’s due diligence that a number of elements of the project’s design would benefit from modification to bring it up to Anglo American’s safety and operating integrity standards and to optimise the value of the asset for the long term,” the company said.

Anglo is also making a change to the leadership at Woodsmith following its integration into Anglo American and ahead of the full project execution phase. Tom McCulley, who has led the development of the Quellaveco copper project in Peru, will take over from Chris Fraser as CEO of Crop Nutrients. This will see Fraser step aside and take on a strategic projects role for Anglo.

“The Woodsmith team is further developing the engineering to optimise the configuration of the project, recognising the multi-decade life of the mine,” Anglo said.

Particular attention is on the aspects identified at the outset of Anglo American’s ownership – namely, the sinking of the two main shafts, the development of the underground mining area, and the changes required to accommodate both increased production capacity and the more efficient and scalable mining method of using only continuous miners, it said.

The sinking of the two main shafts is due to be carried out using Herrenknecht’s Shaft Boring Roadheader (SBR) technology. DMC Mining, a company familiar with the technology thanks to its work sinking shafts at Jansen in Saskatchewan, Canada, was previously tasked with sinking the production and service shaft, each around 1,500 m deep, and two smaller shafts associated with the materials transport system, each approximately 350 m deep. Its contract was ended in 2020.

These improvements will, the company said, require the installation of additional ventilation earlier in the development of the underground mining area.

“Anglo American expects that these changes to the design of the mine infrastructure – which will result in a different, enhanced configuration and therefore a different construction and production ramp-up schedule – will ensure that its exacting standards are met and the full commercial value of the asset is realised,” the company said.

Mark Cutifani, Chief Executive of Anglo American, said: “We are very happy with the high quality and exciting potential of Woodsmith, with the scale and quality of the polyhalite orebody pointing to a quartile one operating cost position and strong margins. This is a very long-life asset and we are going to take the necessary time to get every aspect of the design right to match our long-term vision and value aspirations.

“We have said from the outset that we expect to make improvements and that we will execute certain elements of the construction differently and with a more conservative schedule. We expect to have completed our design engineering, capital budget and schedule at the end of 2022, with a fully optimised value case that recognises the upside potential we see in Woodsmith, and we will then submit the full project to the board.”

In the meantime, construction of the major critical path elements of the project, principally the two main shafts and the mineral transport tunnel, is progressing, with approximately $700 million of capital expected to be invested in 2022, Anglo said.

The plan at Woodsmith under previous owners Sirius was to extract polyhalite via two mine shafts and transport this outside of the National Park to Teesside on a conveyer belt system in an underground tunnel. It would then be granulated at a materials handling facility, with the majority being exported to overseas markets. The company was previously aiming to achieve first product from the mine by the end of 2021, ramping up to an initial production capacity of 10 Mt/y and then full production of 20 Mt/y.

The changes to McCulley’s and Fraser’s roles are effective January 1, 2022. Anglo American has appointed Adolfo Heeren as CEO of Anglo American in Peru, effective from the same date. Heeren will work together with McCulley during the first half of 2022 to ensure a smooth transition from the construction and commissioning phase of Quellaveco into operations, expecting first copper production in mid-2022.