Whitehaven Coal sold less coal in the March quarter while battling low prices, but its flagship Maules Creek project is more than one-third complete.
The controversial NSW mine is the target of a long running campaign that has included legal action and human barricades to delay construction, in protest against the alleged destruction of the Leard State Forest.
More than 90 protesters faced court in Narrabri and a mother and son were arrested after chaining themselves to a gate at a Whitehaven site.
Whitehaven said construction progress at Maules Creek was 36 per cent complete and on schedule and budget.
First coal should be railed in March 2015 and the company was confident it would get Commonwealth approval for its biodiversity offsets package, which involves a package to balance the effects on flora and fauna.
The highly regarded $767 million project would more than double Whitehaven's production to 25 million tonnes a year.
Whitehaven produced 1.81 million tonnes in the three months to the end of March, down 29 per cent on a year ago.
It recently flagged a cut in full year production by up to eight per cent, to between 9.8 million and 10 million tonnes of saleable coal, due to operational problems.
Whitehaven sold 2.29 million tonnes for the March quarter, down five per cent.
It achieved a weaker average price for export thermal coal sales of $US75.19 a tonne, compared to the benchmark Newcastle index, which was down seven per cent to $US78.05 for the quarter.
The reasons included a well-supplied market with little disruption from weather related events, a lack of buying by China based coal customers from the seaborne market, and the end of the high demand northern hemisphere winter.
However, thermal coal demand was growing in South Korea, which is increasing coal in its energy mix, and analysts including Bell Potter have a positive long term view on the company, and coal generally.