Mount Pleasant Optimisation Project

The Optimisation Project proposes extraction of additional coal reserves within Mount Pleasant Operation Mining Leases and an increase in the rate of coal extraction without significantly increasing the total disturbance footprint. The extraction of additional Project coal reserves would be supported by the use and augmentation of existing approved infrastructure.

What does the Optimisation Project include?

The Optimisation Project would include:
  • mining of additional coal reserves, including lower coal seams in North Pit;
  • staged increase in extraction, handling and processing of run-of-mine (ROM) coal up to 21 million tonnes per annum as mining moves west, away from Muswellbrook;
  • increase in average operational workforce to approximately 600 people, with a peak of approximately 830 people;
  • giving up part of the approved disturbance area to compensate for new disturbance areas;
  • rail transport of up to approximately 17 million tonnes per annum of product coal to domestic and export customers;
  • use of innovative mine landform design to provide topographic relief and more natural exterior appearance of waste rock emplacement landforms;
  • development of new water management and coal reject dewatering infrastructure;
  • construction and operation of new ancillary infrastructure; and
  • continuation of the Mount Pleasant Operation through to 22 December 2048.
The Project would provide community certainty for continuation of mining in the region and continued Mount Pleasant Operation’s support for local community groups and suppliers.
As illustrated on the following figure, the Optimisation Project mining rate would be staged, so it increases as mining moves further away from Muswellbrook.

The following figure illustrates the approved area to be relinquished and Project extensions in the Mount Pleasant Operation Mining Leases.

State Significant Development Proposal – EIS

To enable the continuation of the Mount Pleasant Operation past 2026 we are required to submit a State Significant Development proposal.

As part of the proposal, we are preparing an Environmental Impact Statement (EIS) which includes assessments of the Optimisation Project’s potential social, economic and environmental impacts.

You can read more about the State Significant Development process on the NSW Government website.

Social Impact Assessment and Community Survey

A social impact assessment forms part of the EIS. You can read more about social impact assessment on the NSW Government website.

As part of the Social Impact Assessment for the Optimisation Project, a community survey was conducted throughout July. The survey provided the opportunity for participants to express their thoughts on the potential social impacts of the Optimisation Project.

You can find more information regarding the Optimisation Project in the Project Scoping Report prepared to request the NSW Government’s requirements for the EIS.

Please visit the NSW Government Major Projects website to find information on the Optimisation Project, and associated NSW Government advice and requirements. 

What would the Optimisation Project add to the Mount Pleasant Operation?


Approved Mount Pleasant Operation DA 92/97

Optimisation Project

Mine Life

Originally 21 years from the date of grant of Development Consent DA 92/97 (i.e. 22 December 2020).

Extended to 22 December 2026 (Modification 3).

Until 22 December 2048 (i.e. extension of 22 years, allowing for 31 years of mining operations overall).

Mining Method

Open cut mining method incorporating truck and excavator and dragline operations (dragline not envisaged prior to 2026).


Use of dragline subject to feasibility studies.

Run-of-Mine (ROM) Coal Production

ROM coal production at a rate of up to 10.5 million tonnes per annum (Mtpa).

ROM coal production at a rate of up to 21 Mtpa.

Waste Rock Production

Waste rock removal at a rate of up to approximately 53 million bank cubic metres (Mbcm) per annum.

Waste rock removal at a rate of up to approximately 89 Mbcm per annum.

Waste Emplacements

Waste rock emplaced both in-pit, and in out-of-pit emplacement areas.


Relinquishment of the North West Out-of-Pit Emplacement area.

Coal Beneficiation

Beneficiation of ROM coal in the on-site coal handling and preparation plant (CHPP).


Staged upgrades to the CHPP to allow the handling and processing of additional ROM coal.

Coal Loading

Reclaim from product coal stockpiles with coal valves and reclaim conveyors, and loading to trains via a train load-out conveyor and load-out bin.


Coal Transport

Coal transported along the Muswellbrook–Ulan Rail Line and then the Main Northern Railway to the Port of Newcastle for export, or to domestic customers.


An average of three, and a maximum of nine, laden trains per day leaving the mine.

An average of 6.5, and a maximum of 10, laden trains at peak coal production.

Coal Rejects

Coarse rejects are placed within mined out voids and out-of-pit emplacements, and used to build walls of the Fines Emplacement Area. Fine rejects are stored in the Fines Emplacement Area.

As approved, plus fine reject dewatering infrastructure would also be installed on new Coal Processing Plant modules so dewatered fine rejects can be co-disposed with coarse rejects.

Water Supply and Disposal

Water requirements are met from pit groundwater inflows, catchment runoff and make-up water from the Hunter River and the Bengalla or Dartbrook Mines.

Surplus water will be discharged into the Hunter River (or its tributaries) in compliance with the Hunter River Salinity Trading Scheme (HRSTS) and Environment Protection Licence (EPL) 20850. 


Approximate Disturbance Area

Approximately 2,800 hectares (ha) of surface development, exclusive of some incidental components such as water management infrastructure.


Final Landform and Land Use

A final landform that incorporates macro-relief and micro-relief concepts so it does not look “engineered” when viewed from Muswellbrook, and avoids major engineered drop structures where practical.

One final void would remain if mining was to cease in 2026. The full 21 year mine life indicative final landform includes two final voids associated with the North Pit and South Pit open cuts and a smaller third final void located between the two larger final voids.

Development of an integrated waste rock emplacement landform that incorporates geomorphic drainage design principles for hydrological stability, and varying topographic relief to be more natural in exterior appearance.

One final void would remain.

Rehabilitation with a mixture of pasture and forest, with increased revegetation with native tree species on the eastern face of the final landform.


Hours of Operation

Operations are approved to be undertaken 24 hours per day, seven days per week.


Operational Workforce

Average operational workforce throughout the life of the mine of approximately 330 people, and an estimated peak of approximately 380 people.

An average workforce of approximately 600 people, with a peak of approximately 830 full time equivalent operational personnel (including MACH staff and on-site contractor personnel).

Construction Workforce

Construction workforce is expected to peak at approximately 350 people.

Construction workforce may have short-term peaks of up to 500 people.