Opened in 1947 by the state government of the day, Awaba was one of a string of state-owned mines under Lake Macquarie developed for a growing roster of power stations.

It stayed in public ownership until 2002, when Centennial bought Awaba and the rest of the government's Powercoal mines for $331 million.

Centennial was taken over last year by Thai group Banpu for $2.5 billion, and delisted from the Australian stock exchange.

Awaba mineworker Ross Smith said the Banpu takeover had nothing to do with the closure of the Awaba mine, which had been running out of coal for years.

"It had closed down for a while and was then reopened and we've been going back doing pillar extraction, getting the last bits of coal out of areas that were in some cases mined many years ago," Mr Smith said.

"It's good quality coal, in fact we've been exporting some of it recently, but that's the end of it here in the Great Northern seam.

"Centennial's Newstan Lochiel mine will be going in through the seam underneath, us but our last shift at Awaba is on December 23."

Awaba was a small bord-and-pillar mine producing about 800,000 tonnes of thermal coal a year in recent years. Eleven of Awaba's 85 workers would retire at the end of the year.

In 1993, the Coalition government told the Labor opposition there was "no identifiable export market for Awaba and Newvale [which shut later that year] nor are there any domestic contractual arrangements. As such, it is considered highly unlikely that the mines represent attractive acquisitions for any potential purchaser."

An estimated 10 million tonnes have been mined from Awaba since then, thanks to a tripling of coal prices over that time.