Sally Malay said up to 600 tonnes of material slipped down the North East wall partially burying a haul truck on Sunday. No personnel were seriously injured by the collapse.

Sally Malay managing director Peter Harold told MiningNews.net there were three options available to the company and a decision on the direction would be made next week.

Harold said Sally Malay and Roche Mining could conduct a risk assessment and decide to keep going, wait until the dry season, or decide to extract the ore from underground.

"Our chief operating officer Richard Jordinson has been up there and is due back tonight [Wednesday]," Harold said. "I'll have a word with him tomorrow [Thursday], so I think sometime late next week we'll know which way we're going."

The company said the cause of the slippage was unknown at this stage, but early indications are that the heavy rain experienced recently at the site maybe a factor. The pit was due for completion by February.

Sally Malay said the impact on nickel production is expected to be minor, with around 40,000 tonnes of ore on the ROM pad (about 2-3 weeks milling), and the ore remaining in the open pit shell design, estimated at 100,000 - 140,000t likely to be accessible from underground in the future.

"We had a good run in the last quarter, we were ahead of budget by about 265 tonnes of nickel" Harold said. "With a bit of luck and some good management you might not even see the numbers at all."

In addition, Sally Malay said contingency plans had been implemented with the focus on bringing additional underground stopes online ahead of schedule. Sally Malay is producing around 8700t of contained nickel per year from the operation.

Shares in Sally Malay hit a 52-week high of $1.12 in March before slipping to a 52-week low of 61c in November. The stock shed 3.5c (5.1%) during afternoon trade to 65.5c.