ORICA has been cleared for a full restart of its Kooragang Island operations.
EPA director Gary Davey said the Orica start-up committee had recommended the ammonia plant, which has been shut since August, be cleared to restart.
Mr Davey said Orica had done all that was required of it.
He said Orica had been issued with a notice that allowed it to restart the ammonia plant from tomorrow.
It was a start-up of the ammonia plant that began the controversy over Orica from early August.
The ammonia plant makes ammonia from a feedstock of natural gas, with the nitric acid and ammonium nitrate sections of the plant converting the raw ammonia into explosives and other products.
These sections are already operating using ammonia brought onto the site as feedstock.
Mr Davey said the EPA had put extra conditions on Orica’s operating licence to ensure its operation met acceptable standards.
Resumption of production from the Kooragang Island plant will start to ease an acute shortage of explosives for the Hunter’s open-cut coalmines.