The Australian Construction, Forestry, Mining and Energy Union (CFMEU) said Tuesday the Rio Tinto's redundancy package for its Blair Athol coal mine discriminates against union members.
The mine, near Clermont in Central Queensland, is closing down in less than two months after almost 30 years of production. The announcement came after Rio pushed forward the closure date, slashed jobs at the nearby Clermont coal mine and closed its offices in Sydney.
Clermont Region general manager operations Dawid Pretorius said at the time that the Blair Athol had been progressively scaling back production in a transition towards closure since 2010.
"After close to three decades, Blair Athol Mine's coal seams are largely mined out and the time has come to finish production," he said.
"Coal mining has a long and proud history at Blair Athol, dating back to the late eighteen hundreds when coal was first discovered in this area. At its peak, Blair Athol Mine was Australia's largest exporter of thermal coal, blessed with uniquely thick coal seams.
The union is trying to finalize a new agreement, as workers think the current proposal gives unionized workers less than to those on individual agreements.
"Depending on how long you've been at the mine, that market allowance could be up to many … thousands of dollars," CFMEU spokesman Glenn Power told ABC News.
But a spokesman for Rio Tinto told ABC News it believes the current deal, including redundancy payouts, are fair.
Unionized workers will vote next week on whether to go on a strike.