At approximately 6:25am on 31 October 2013, a seismic event occurred at the Nickel West Leinster Perseverance Underground operation.
Employees underground at the time followed site safety procedures and made their way to a secure refuge chamber where they had access to water and communications.
All individuals were safely brought to the surface at 3.30pm the same day.
While experts assess the impact on operations, mining at Perseverance Underground has been temporarily suspended.
A small crew of employees is able to safely continue working underground to re-establish access, carry out inspections, assessments and maintenance of essential services.
Underground personnel not engaged in these tasks have been informed that they are not required at work until further notice.
Our Nickel West operations at Mt Keith, Cliffs, Kalgoorlie, Kambalda and Kwinana were not affected by the seismic event and are currently operating as normal.
While Kwinana nickel refinery production will be maintained in the short term, the temporary suspension of the Perseverance Underground operation is expected to result in a reduction of total saleable nickel production at Nickel West in the December 2013 quarter.
Any impact on production will be reported in the quarterly BHP Billiton Operational Review.
See the News Release.