The mine has been on care and maintenance status since early June as a result of the currently unfavourable nickel price environment.
Belvedere said it would let the mine water levels rise from the 620 metre (m) level to the 430 metre level. This is expected to take around three months.
Around 120,000 tonnes of developed ore, equivalent to around three months of underground production, will be affected by the water rise, but the main mine infrastructure, and the West ores and South ores, will be unaffected by the flooding.
It is possible that the company will resume the pumping out of water at the lower levels should nickel prices improve. Meanwhile, environmental permitting for re-opening the open pit has been received but current nickel prices are too low for a restart, even with the cost synergies of the open pit.
"Due to the continuing low nickel prices, and in recognition of the higher marginal cost of production of the deep ores, the company intends to let the lower levels of the mine flood as a cost saving measure, whilst leaving the majority of the underground mine infrastructure and the shallower west and south ores intact,” revealed chief executive officer, David Pym.
“The exploration drilling at South Hitura has been successful in substantially extending the mineralisation by more than 100m vertically down-dip and the strike by more than 100m to the south. The zone remains open, and an updated resource estimate will be completed in due course,” he added.
The company said actual grades at South Hitura are similar to the North Hitura ores, but preliminary flotation tests indicate much higher recoveries of nickel in concentrate with up to 84% recoveries achievable in bench scale tests, compared to the 60-70% recoveries typical of the north zone.
Highlights of the drilling included: 22.75 metres at 0.84% nickel, 0.8% copper and 0.06% cobalt from 82.29 metres at hole R-2189; 11.5 metres at 1.13% nickel, 0.24% copper and 0.09% cobalt from 152.55 metres at R-2221; and 18.85 metres at 0.76% nickel, 0.29% copper and 0.06% cobalt from 140.3 metres.
At the nearby Kopsa gold/copper project, the preliminary economic assessment is due for completion at the end of this summer, while work on environmental permitting is going on at the same time.