FONTERRA will close its Dennington factory.
About 100 staff members were advised of the decision at an on-site meeting on Wednesday afternoon.
Frank Kelly, the site's delegate for the National Union of Workers, said staff were told there would be a meeting at 3.30pm just hours before.
"The people on-site were notified there was a meeting at 3.30pm, the people off-shift were called and told to come in."
Mr Kelly said staff were told the factory was closing in November due to a lack of milk.
"There was no warning but the writing has been on the wall," he said.
"We've only been running at about 30 per cent capacity, so something was going to happen."
Mr Kelly, who was set to mark 40 years at the factory in October, said staff members were in shock.
"It's like anything - you knew something was going to happen but it's still an absolute shock," he said.
"You've got a handful of people who are probably happy to go because they're at that stage of their life but the majority of people have got to find a job somewhere."
There was no warning but the writing has been on the wall.AMWU's Frank Kelly
Mr Kelly said a lot of staff members feared those prospects were bleak.
"The other milk plants, they're apparently not travelling so well either," he said.
Mr Kelly said it was tough to digest the news, but sadly staff had become accustomed to meetings about bad news occurring with little notice.
He said staff would return to the site for meetings with management on Thursday, but the plant was not expected to be operational again until Monday.
A company spokeswoman said staff had been advised of the decision on Wednesday afternoon.
"We have spoken to our staff this afternoon and advised them that we are closing the factory," she said.
"It's important to us that we talk to our people first and we will release more information to the media tomorrow morning."
A source told The Standard the decision would affect 98 staff members at Dennington and only a handful were likely to be redeployed.
The source also said there were only about 200 suppliers to Fonterra's Dennington and Cobden plants.
The shock decision comes after it was revealed in January 2018 that the Dennington factory would undergo an $8.6 million expansion.
Fonterra took over the Dennington plant in August 2005, after Nestle Australia announced it would stop manufacturing powdered milk in Australia to focus on higher value-added products.
About 80 jobs were lost when Fonterra took over.
At the time a Nestle employee told The Standard that staff were given no warning and the meeting advising them of the closure lasted 10 minutes.
"They wanted us to ask questions. Everyone was too dumbfounded to ask questions."
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