300 coal workers have returned to work after their employer tore up a contract with Griffin coal mine last week.
The move comes after months of alleged missed payments by Griffin Coal’s owner Lanco Infratech.
However a last minute deal has seen Griffin sign on the 300 workers so production at the site can continue.
Griffin executive general manager David Trench said the company had its own machinery to run the operation.
CFMEU secretary Gary Wood said around 50 people might miss out on reemployment, ABC reported.
"We're obviously seeking to increase the number of people who transfer their employment but at this point in time there's looking to be around about 50 to 60 people who will not be given an opportunity to continue employment,” Wood said.
The viability of the plan as a long-term strategy has been called into question given the coal mine owner's troubled finances.
Lanco's debt stood at $US5.9 billion in March this year, and the company said it would sell power projects to raise $825 million.
The company said discussions were underway with “some strategic/financial investors”.
Griffin mine is the primary source of coal for the Bluewater power station, which supplies energy for WA’s southwest, as well as 15 per cent of the state’s overall supply.
"If they [Lanco] keep going, it's pointless, the mine will go broke; they are pouring in money every month and not making anything,” Murray said.