Orica has announced it will restart its ammonia plant near Newcastle, almost six months after it leaked hexavalent chromium fumes over more than 70 homes.
Orica said on Sunday that it was likely the Kooragang Island plant will resume operations on Tuesday.
"Residents may see some steam coming from the plant on Monday as we warm up the plant and conduct standard equipment checks," site manager Sean Winstone said in a statement.
"We will continue the restart at a cautious pace with a focus on safety."
Orica said that there was a chance that gas from the vent stacks would ignite but that there was no risk to the community, the environment or the plant from the gas flares.
Orica announced in January that it would dely reopening the site after it was unhappy with the performance of one of the compressors on the site.
The plant was shut down in August after hexavalent chromium fumes leaked near more than 70 homes in the beachside suburb of Stockton, near Newcastle.
In December, the company confirmed there had been a "contained leakage" of about 3000 to 4000 litres of sulfuric acid at its Port Kembla facility, on the NSW south coast.
NSW Premier Barry O'Farrell has warned Orica he will close its Kooragang Island plant if there are any more leaks.