UP to 1400 workers face uncertainty after resources giant BMA announced it would shut Dysart's Norwich Park mine in a month.
Of those, 490 are permanent employees of the company and will likely benefit from redeployment to other operations, its Saraji mine in particular.
The coking coal operation - partly owned by BHP Billiton - will "cease production indefinitely" after 6pm on May 11.
A BHP spokesman said some staff would be given voluntary redundancies, but many would find work inside the company.
"The first obligation is to our direct employees - every effort will be made to redeploy them," he said.
Construction, Forestry, Mining and Energy Union district president Steve Smyth said the Dysart community will be devastated by one of the towns' coal mines shutting down.
"It's a kick in the guts for Dysart," he said.
"Apparently we are in a boom. I'd hate to see when a bust comes."
Mr Smyth said the majority of the union's 300 members that were permanent Norwich Park Mine workers lived in Dysart.
"We will have other members that are with the contractors," he said.
"We haven't received contact from the contractors yet."
The union is expected to meet with BHP at 10am today to find out more.
In a statement released yesterday, BHP explained Norwich Park had been "losing money for several months" as it was hit by falling production, rising costs and lower coal prices.
The decision was made after a seven-week review into the project.
BMA asset president Stephen Dumble said the closure was not done lightly, but said there was no escaping Norwich park was "not currently viable".
"While recent industrial action has had an impact on production, the mine has been unprofitable for some months," he said.
"As a result, we have had to take urgent steps to both stop the losses and find the best way to secure the operation's longer term future."
Norwich Park is one of seven mines targeted for strike action to run from tonight until Saturday.
Mr Dumble said the mine would remain closed until a viable solution was found.
"We understand that this decision will have a significant impact on our employees, their families and the Dysart community and we are committed to supporting them during this period," he said.
This is not the first time this mine has struggled to survive.
In May, 2009, BHP partially shut down the mine, ran it on a skeleton staff and gave 100 miners a pay-cut due to "difficult market conditions".
Mr Smyth was confident the 490 permanent staff would find work, but the fate of contractors remained unclear.
"They may struggle," he said.
"BMA or BHP staff are given first preference in the enterprise agreement."
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