Zimplats Holdings has established a three-year plan to re-develop its Bimha underground platinum mine in Zimbabwe. The mine was shut down in August 2014 due to unstable ground conditions following a major underground collapse in July that affected nearly 50% of the mine footprint (E&MJ, September 2014, p. 18).
In July 2014, the company announced that a collapse within a section of the underground working area had been triggered by accelerated deterioration of ground conditions associated with a major fault which intrudes throughout the mining area. In the following weeks, ground conditions continued to deteriorate and Zimplats decided to to implement closure procedures.
Since then, Zimplats personnel and independent experts have undertaken extensive monitoring and studies to identify the root cause of the collapse, assess mine stability, and establish a new mining platform in terms of rock support designs and mining methods. These studies provided the basis for a new mine layout and design that entails re-development of the mine along strike, 30 m above the current mine footprint.
In the meantime, Bimha mining fleets have been re-deployed to the other Zimplats mines.
Zimplats produced 240,000 oz of platinum in its 2014 financial year ended June 30, 2014. The company estimates the Bimha shutdown will result in the loss of about 70,000 oz during the current financial year.