Project data
Overview
Thiess began mining at the Mount Pleasant Operation in the Upper Hunter Valley in November 2017, following a successful five‑month mobilisation period.
Since 2017, our work at Mount Pleasant has been defined by strong local engagement, high performance and a commitment to safe, sustainable mining that supports long‑term growth for our client and community.
Located 2.5 kilometres from Muswellbrook, the greenfield open-pit mine contains an estimated 474 million tonnes of reserves and is operated by MACH Energy.
Since commencement, Thiess has delivered a full suite of mining services, including mine planning and engineering, drilling and blasting, loading and hauling, run‑of‑mine rehandling, asset maintenance, and progressive rehabilitation. The team safely developed site systems, mobilised plant and equipment from across four states, recruited and trained the workforce, prepared explosives facilities and completed initial topsoil stripping. In the first year of operations, the project achieved a TRIFR of 0.
Thiess continues to support MACH Energy in increasing production to 10.5 million ROM tonnes per annum, while building a high‑performance, locally based workforce. More than 80 per cent of the Mount Pleasant team live in the region, with strong representation of female, Aboriginal and Torres Strait Islander employees. Thiess also partners with a local Indigenous organisation to provide labour, machinery and cleaning services, reinforcing meaningful community participation.
In 2026, Thiess secured a six‑year contract extension through to 2031, expanding its scope to support the mine’s long‑term growth. Under this new agreement, Thiess will continue delivering full mining services, enhanced fleet capacity, strengthened infrastructure and innovative technology solutions to meet MACH Energy’s production and sustainability objectives. The extension reflects the strong partnership formed since the mine’s inception and Thiess’ ongoing commitment to safe, productive and responsible mining operations.
Related Resources
12 January 2026 | Thiess secures six-year contract to expand operations at Mount Pleasant
1 January 2026 | Improving biodiversity outcomes at Mount Pleasant Operation
27 June 2022 | Young miners tour Mount Pleasant Operation in the Hunter Valley
12 August 2021 | Thiess awarded 4.5 year Mount Pleasant extension
9 March 2021 | Mount Pleasant Operation recognised for industry-leading rehabilitation practices
