Leighton loses out as BMA finds cheaper alternative THE Leighton group yesterday felt the impact of moves by miners to slash cost bases amid falling commodity prices when BHP Billiton Mitsubishi Alliance (BMA) prematurely terminated a contract worth up to $260 million for a cheaper alternative. BHP decided to move the pre-strip contract with Leighton Contractors at the Peak Downs coalmine in Queensland to the smaller Perth-based HSE Mining, prompting the cancellation of the contract for the Leighton Holdings subsidiary that was scheduled to run until 2015.