Up to 4000 workers, representing members of three unions and across seven BMA mines, are holding ballots on June 2 on possible strike action as pay negotiations are stuck in deadlock.
The seven BMA mines include the Blackwater, Peak Downs, Saraji and Gregory open cut coal operations, along with the Crinum East longwall mine, with strike action possible in early June just as BMA seeks to ramp up production after months of lower productivity due to floods and cyclone Yasi.
Negotiations for a new Enterprise Agreement started in November but by the May 16 expiry date of the old EA no agreement had been reached.
CFMEU spokesman Steve Pierce said his members were concerned about the disparity of levels of pay between mine workers and contractors. The unions were also pushing for job security and training opportunities.
"Strike action is always the last resort," he told AAP.
"It's not an action we take lightly or use at the drop of a hat.
"We're unable to reach a reasonable compromise at this point in time."
A spokeswoman for BHP told ILN discussions with the combined unions were ongoing but key differences remained.
“The unions are pressing claims that would create major cost, productivity and competitiveness impacts for the business, as well as wanting to reintroduce a range of outdated industrial practices,” she said.
“As these are beyond reasonable expectations, discussions have the potential to extend for some time.”
In April the unions formed a Single Bargaining Unit to launch a social media and press campaign against BHP Billiton.
The SBU webpage is housed in the Construction Forestry Mining and Energy Union’s website, with the Electrical Trades Union and Australian Manufacturing Workers' Union also involved in the SBU.
Earlier this year the Australian Mines and Metals Association (AMMA) released a survey of its members showing their growing discontent and frustration with Australia’s new fairer industrial laws.
Its survey of 76 member companies found an increasing hostility towards key aspects of the Fair Work Act.
Union right of entry was a major complaint as employers reported a growing union presence in their workplaces.
In April last year 58.8% of respondents reported an "active" involvement by unions, but by October this had increased to 69.1%.
AMMA chief executive officer Steve Knott said the survey showed the IR environment facing Australia's resource industry had become "substantially more difficult".
He said it was clear that increased union activity both in negotiations and in workplaces was having a "major impact on levels of confidence in workplace relations arrangements under the Fair Work Act".