Vale’s application to continue mining at the Integra open cut operation is also delayed along with the environmental assessment for Yancoal Australia’s proposed southeast open cut at its Ashton mine.

A government spokesperson told the ABC these projects were on hold as the department needed additional air quality modelling and assessment work.

In October last year, an industry and government plan to establish the Upper Hunter Air Quality Network was unveiled.

This network will establish 14 dust-monitoring stations in the region but the project is still in the design stage with no sites yet selected.

Last week, the state government released data on Upper Hunter air quality from industry-monitored sites in 2005-09.

The state’s environment department said it released the data to assist the Department of Health in its “review of community concerns that air pollutants from coal mining and power generation in the Upper Hunter are impacting on health”

In another sign of the government’s tougher stance on the issue, Bickham Coal’s plans to build a 36 million tonne per annum open cut mine in the region were rejected about three weeks ago.

The state’s planning assessment commission said the project would threaten the thoroughbred industry.

The Ravensworth project would extend open cut mining for another 29 years and expand surface infrastructure for the Ravensworth longwall operations.