PERTH (miningweekly.com) – A supplementary study for ASX-listed Aquila Resources’ Washpool hard coking coal project, in Queensland, has introduced a new mining plan for the operation that would increase output.

The supplementary study to the definitive feasibility study (DFS) was undertaken to investigate the blending of Washpool coal with a lower-ash semi-hard coking coal, as well to revise the mine plan, surface infrastructure, capital costs and operating costs.

The original 2011 DFS estimated that capital expenditure (capex) of about A$335-million would be required to deliver an opencut operation producing seven-million tonnes a year run-of-mine (RoM) coal, to produce 2.6-million tonnes a year of hard coking coal, over a 16-year mine life.

At the time, the project was expected to have an operating cost of around A$125/t free-on-board (FoB).

Aquila reported on Tuesday that the supplementary study proposed the production of 7.2-million tonnes RoM coal, to produce 2.9-million tonnes hard coking coal, over a 15-year mine life.

Upfront capex of A$358-million would be required to develop the project, while operating costs have now been estimated at A$122/t FoB.

Meanwhile, blending studies on the Washpool product also indicated that a blended hard coking coal with an ash content of around 10% could be delivered, if the Washpool coal is blended with a lower-ash semi-hard coking coal.

The test demonstrated that the coking properties of Washpool coal significantly improved the coke strength of the coal it was blended with, while the blend coal generated higher coal strength.

Aquila chairperson Tony Poli pointed out that since the supplementary study was started, the spot price for hard coking coal had fallen by nearly 20%, to a five-year low.

However, he expressed his confidence that the coal prices would recover in the medium term, saying that in the interim, Aquila would advance discussions with various parties on securing investors and offtake partners for the Washpool project, as well as the company’s other operations.

These discussions were expected to assist Aquila in prioritizing its future development efforts beyond the construction of the Eagle Downs coking coal project.