The High Court of Australia has rejected an appeal from mining giant BHP to overturn a Same Job Same Pay ruling at three of its largest Queensland coal mines.

The ruling focused on labour hire workers employed by Operations Services (OS) at BHP Mitsubishi Alliance’s (BMA) Goonyella Riverside, Saraji and Peak Downs mine sites in the Bowen Basin.

The Fair Work Commission originally ruled workers with OS, a subsidiary of BHP, were entitled to the same pay as their directly employed counterparts, which was later upheld by the Federal Court.

BMA has previously said in a statement that it had paid the more than 2,000 OS mineworkers affected by the ruling increased wages while the matter progressed through the courts.

The Mining and Energy Union said the ruling would mean pay rises of between $20,000 and $30,000.

A train wagon filled precisely full with coal

BHP owns five mines in Queensland’s Bowen Basin, three of which are covered by this Same Job Same Pay order. (ABC Tropical North: Melissa Maddison)

In a decision published on Thursday, the High Court ruled BHP’s proposed appeal of the Federal Court decision had “insufficient prospects of success” and refused “special leave”.

The union’s general vice-president, Stephen Smyth, said the decision marked the end of the road of BHP’s fight against the Same Job Same Pay regime.

“BHP were the last ones holding out,” he said.

“These workers have worked side by side with full-time employees on the same shifts and the same tasks.”

He said while the OS arrangement was unique to Queensland, the High Court decision did set up “interesting applications” at other mines in New South Wales and Queensland.

Steven Smyth in a CFMEU polo shirt standing in his office in front of a map, which says "Queensland Coal" on it.

Stephen Smyth says BHP fought the order at every step. (ABC News: Katherine Gregory)

“This will make it easier for us, our members and others at mine sites to get other applications up,” he said.

The Australian Resources and Energy Association has previously estimated the ruling would cost BHP around $1.3 billion a year.

BHP was contacted for comment.

In previous statements, a spokesperson for the company said it was “concerned” other contractor businesses would be “captured by Same Job Same Pay orders”, which would act as a “drag on productivity”.

The company had previously maintained OS was a “mining services provider”, which are exempt from the orders.