The mine would need to address the moisture issues and resolve lingering teething problems in the second half of 2013 if it was to achieve world’s best practice in production, it said.

“With the current 6 million tonnes per annum longwall production target based on 65 hours per week upside remains if the operation is able to push operations towards industry best practice

of 90 hours per week,” Macquarie said.

“The underground handling capacity and approval is for up to 8Mtpa recommissioning of the

Stage 1 crushing system will lift surface facility capacity to more than 10Mtpa.”

The Narrabri longwall was producing at an annualised rate of 2.7Mt in the first half. Total output, including development coal, was 1.6Mt.

The longwall is operating at capacity for periods, just not consistently, achieving 30,000t

per day and 130,000t per week, according to Macquarie.

Narrabri product moisture was an issue in the first half and would continue to impact revenue into the second half of 2013, Macquarie said.

“The issue is expected to be resolved as longwall production tonnes increase and the Stage 1 raw

coal crusher is recommissioned,” it said.

“Further operational fixes include additional dewatering of the raw coal from the drift conveyor.”