The total resources increased 22% from last year to 122.6Mt, with the big shift being the amount of resources that were upgraded into the ideal measured category.

The upgrade resulted in a reduction of 6.3Mt in the indicated category, which is now set at 31.5Mt.

Inferred resources were reduced to a mere 1.8Mt, while they were 31.7Mt last year.

The Middlemount JV secured a long-term haulage contract with Pacific National last month, which will begin at the start of 2012 to support 3 million tonnes per annum of production.

Macarthur plans to kick off stage 2 development of the mine in mid-2011.

Once complete, this ramp-up is expected to lift raw production capacity of the coking and PCI coal mine to 5.4Mtpa for the next 19 years.

Macarthur has a 72.48% interest in Middlemount while Noble has a 27.52% stake.

But Gloucester Coal has proposed a deal to acquire Noble’s stake of Middlemount which will also reduce Noble’s stake in Gloucester to 61%.

Macarthur shares are down 3c to $12.41 as post-election uncertainty hits the local bourse.