The Australian Transport Safety Bureau's preliminary report over the November 2018 derailment of BHP Group's iron ore train in Western Australia found that the mining giant's rail crews mistakenly applied handbrakes to an empty iron ore train and not to the runaway ore train.
The train, traveling on BHP's Newman-to-Port Hedland railway, was deliberately derailed by the miner's remote control center in Perth about 119 kilometers from its destination.
The regulator said in its March 12 report that the rail maintenance crew applied manual brakes on an empty train traveling the other direction, which had stopped while the miner sorted out the main incident. The fully laden train had been running for 50 minutes at a top speed of 162 kilometers per hour over 91 kilometers when the mistake was discovered.
A spokesperson for the miner said applying manual brakes to the correct train would not have been enough to stop the rollaway event, The West Australian reported the same day.
BHP Western Australia Iron Ore President Edgar Basto said the findings reaffirmed the company's internal investigation, saying the accident resulted from "procedural noncompliance by the driver, as well as integration issues with the electronically controlled pneumatic braking system to the rail network."
The final report is due later this year. The Australian regulator said the investigation is continuing, and it will look at a number of factors, including the design of train braking systems the operator used and procedures in the operator's safety management system.
In February, BHP reached an undisclosed settlement with a train driver who filed an unfair dismissal claim in the wake of the derailment.