Last month the semi-autogenous grinding mill motor drive bearing failed, bringing the 2.9 million tonne per annum Edna May plant to a halt.

The bearing was replaced, however, problems remained.

During several restart attempts it was found to be overheating or arcing, which led the Ramelius team to deduce the mill motor was faulty.

Ramelius' inventory management policy requires critical spares to be kept, meaning a mill motor was immediately available.  

From there it was four days' work to install and commission the replacement motor.

In all, including the initial diagnosis period, the mill outage lasted 173.5 hours - more than seven days.

Nevertheless, Ramelius still met its guidance range of 65,000-70,000 ounces for the March quarter.

Between Edna May and its Mt Magnet operation, Ramelius turned out 66,029oz for the three months to March 31.

The Edna May operation uses a standard carbon-in-leach gold processing plant.

The plant has two-stage crushing, the SAG mill, a ball mill, a gravity circuit and leaching.

About 50% of Edna May's gold is recovered via the gravity circuit.

According to Ramelius the plant's total recovery is 93%.