The miner may cut its labor costs by 10%, which could involve layoffs among its 35,000 staff.
Case centres on a 2018 toxic spill at the Badila oilfield, equivalent in volume to 34 Olympic-sized swimming pools.
The Canadian miner has reportedly engaged law firm Thomson Geer to finalize a prospectus for listing in the ASX before Christmas.
The three executives, including CEO Terry Holohan, were freed from detention on Wednesday.
