FQM Australia Nickel Pty Ltd fined $40,000 following tank rupture

The company was fined after approximately two million litres of hot slurry was released at its Ravensthorpe Nickel Operation.
Date: Tuesday, 03 January 2017

First Quantum Minerals (FQM) Australia Nickel Pty Ltd has been fined $40,000 in Kalgoorlie Magistrates Court in relation to an incident on 14 December 2014 when a ruptured tank spilled approximately two million litres of hot slurry containing 1.5% sulphuric acid at the company’s Ravensthorpe Nickel Operation.

The release of slurry destroyed infrastructure, including critical electrical equipment which cut the power supply to the entire site.  When the slurry was in the tank, it was maintained at a temperature of 101.3 degrees Celsius.

Three employees, who were working in a control room approximately 50 metres from the tank, were initially trapped by the wave of slurry. They eventually escaped without injury.

The tank which ruptured, tank 9, was one of a number of tanks used in the nickel extraction process, which constituted an Atmospheric Leach Circuit.

In February 2010, FQM acquired the Ravensthorpe Nickel Operation and commenced the start-up process.

By May 2012 tanks in the Atmospheric Leach Circuit required repairs due to holes appearing in the outer steel shell.  FQM adopted a repair method involving epoxy resin injection and welding patches to the outer shell.

On 30 September 2014, FQM identified a number of holes in the outer steel shell of tank 9 that required repair work.

At the time the catastrophic rupture occurred, holes in tank 9 had remained unrepaired for two-and-a-half months.

The slurry escaped the tank and travelled down the exterior of tank 9, corroding the outer steel shell and resulting in the catastrophic rupture of the tank.

Department of Mines and Petroleum Mines Safety Director and State Mining Engineer Andrew Chaplyn said the company was aware of the need for regular inspections and repairs of the tanks in its Atmospheric Leach Circuit, and the risks if those repairs weren’t done.

"Its failure to carry out an effective maintenance program led to the catastrophic failure of this tank," Mr Chaplyn said.

"The event had the potential to seriously injure or kill workers in the vicinity of the tank and was entirely preventable."

The company was charged with failing to provide a safe working environment and pleaded guilty on 16 August 2016.

The court took into account the company’s early guilty plea in handing down its sentence.