Photo by: Bloomberg
PERTH (miningweekly.com) – Copper miner Aditya Birla was hoping to have the prohibition notice on its Nifty mine lifted, after presenting the results from its two-stage probe drilling to the Western Australian Department of Mines and Petroleum (DMP).
In March this year, the DMP suspended all mining operations at Nifty after a sinkhole was discovered.
Aditya Birla, which was tasked with investigating the sinkhole, said on Monday that Phase 2 of the probe drilling had discovered that the risk of water or mud in-rush into the mining area had been significantly reduced by the dewatered aquifer conditions above the Nifty reserve, and the dewatering of the pit sump.
Further, the voids intercepted during the probe drilling indicated that there were stope voids that could continue to self-propagate and that the risk of air blast from open voids in the sinkhole was minimal. The probe drilling also revealed that the risk of creating a new sinkhole has been mitigated by the identification of potential mobilisation points, with plans to pastefill these as soon as mining activities resumed.
Aditya Birla said the company had turned its focus to developing a detailed mining schedule while it awaited a DMP decision, and was preparing to establish start-up requirements.
The exact timing of the operational restart at Nifty was still uncertain.
Meanwhile, Aditya Birla had sought expressions of interest for voluntary redundancies at the project site, with between 109 and 350 redundancies eyed.
The company said that acceptances of the voluntary redundancies would not undermine the restart of operations.