The closure of Bell Bay's Tasmanian Electro Metallurgical Company would be the "worst case scenario", but the region would recover, according to stakeholders.
South32 confirmed on Thursday that it will look to close, divest or maintain its manganese alloys smelters in Tasmania and South Africa, amid changes in market dynamics. A further update is expected in October.
George Town deputy mayor Tim Harris said there was a lot of angst in the community in light of more than 300 potential job losses.
"It was certainly a shock, but it's not all doom and gloom just yet," he said.
"I imagine a lot of local businesses will be tightening their belts. It's a town that has lived on industry for the past 50 years.
"We need to look forward with optimism that things will fall into place. And if it doesn't, we need to ensure we are supporting those who need it."
In other news:
The Bell Bay Industrial Precinct is responsible for 59 per cent of all Tasmania's manufactured exports.
Launceston Chamber of Commerce chief executive Neil Grose said if TEMCO was to close, the ramifications would be felt state wide.
"It does have a very broad impact on the overall industrial economy, because there is the supply chain that goes with the factory," he said.
"It is not just the 300 people that work on that site. They rely on a whole range of other imports that come in. Some of those are quite significant to the state."
Bell Bay Advanced Manufacturing Zone project officer Susie Bower said the precinct would be ready.
"The whole reason this group was set up, was for this exact reason - in case either of the big players decided not to be there anymore," she said.
"Big companies do this all the time. It is part of their process, and part of being in a competitive global market.
"We want to make sure that if anything happens, the community is OK, the employees are OK, their kids that go to school at George Town are OK."
Ms Bower said there were numerous investment opportunities poised for Bell Bay, including the $54 million veneer mill expected to be partly operational in August, bringing 70 full-time equivalent jobs.