The Tiwai Point aluminum smelter is proposing to cut jobs again as it fights for survival.
New Zealand Aluminium Smelters wants to shed 31 maintenance roles at the Southland plant after it cut 100 jobs last year from a workforce of 700.
The plant accounts for more than 10% of the region's economy.
Under heavy financial pressure from falling income and an unresolved standoff with Meridian Energy over power prices, nervous workers are leaving and every part of the smelter is being reviewed.
Acting general manager Stew Hamilton told the smelter's 180 maintenance staff on Tuesday he proposes that another 31 jobs go.
In a statement on Wednesday, Mr Hamilton said it has to get back to being profitable. He said 42 jobs are vacant at the plant and affected employees will be re-deployed to other roles wherever possible.
A final decision is expected on 2 September after staff are consulted.
The Engineering, Printing and Manufacturing Union's says more job losses show the plant's standoff with Meridian Energy has to be resolved.
EPMU's director of organising Alan Clarence said Tiwai's workers have been under a cloud of uncertainty for months and the job cuts are another result of that.
Mr Clarence said the Government needs to urgently step in to resolve the matter.
The smelter and Meridian Energy said they have not yet reached a deal and talks are continuing.