Loader operator Port Waratah Coal Services (PWCS) said yesterday that Saturday's Whittingham derailment cost the industry 419,000 tonnes of coal movement while track and loader maintenance cost another 151,000 tonnes.

PWCS would not put a dollar figure on the losses but Hunter steaming coal has been bringing $100 a tonne, putting the cost at about $60 million.

Despite the presence of more than 500,000 tonnes of coal at the port's Kooragang and Carrington coal terminals, none of the partial cargoes were enough to assemble a full cargo, meaning that all five of the port's coal terminals sat empty.

Operations are expected to return to normal during the week but a weekly report published yesterday by the Hunter Valley Coal Chain Co-ordinator shows Newcastle coal experts are already 10 per cent behind target for the year.

Co-ordinator spokesman Jonathan Vandevoort said the derailment and four days of scheduled track maintenance would inevitably add to the shipping queue.

State Government rail investigators said the 30-carriage grain train was on it way to Werris Creek when it derailed.

Track operator Australian Rail Track Corporation said that it had the line to Newcastle open and full services were expected to resume at about 1am today.