Undertaken by consultancy Xenith, the project’s Aries, Pollux and Pisces seams were considered suitable for longwall mining, with 4Mtpa selected out of a range of 2-5Mtpa for operations at a similar depth.

The project hosts 201 million tonnes of inferred resources with the key seams ranging from 283m to 451m in depth.

Located close to existing rail, coal load-out and haul road infrastructure, the longwall project has an initial capital expenditure estimate of $A860 million and is expected to host operating costs in the realms of $90-130/t with $113/t assumed under the 4Mtpa base case scenario.

While the project is targeting a low-volatile, pulverised coal injection-grade coal, further investigation will look into the possibility of produce a higher-return, semi-soft coking coal from the key Aries seam.

Coal quality analysis so far had identified crucible swelling number values of up to 7 from this seam. While average seam ash was in the range of 20-25%, a coal preparation plant is expected to bring this down to 9.5% for a low-sulphur product with an energy value of 7570 kilocalories per kilogram and inherent moisture of 1.5%.

“Our assessment to date has reviewed a number of options for the development of the Mackenzie Project,” Cougar chairman Andrew Matheson said.

“The results to date are encouraging both from coal quality and project cost perspectives and with this improved definition of the Project we will continue to pursue our options with respect to investment into Mackenzie at the project level.”

Cougar shares are unchanged at 0.3c.