Orica has today restarted its Newcastle ammonia plant in Australia following the completion of repair work at its plant and pre-start testing.
The New South Wales Environmental Protection Authority closed the plant indefinitely after ammonia vapour escaped from the site on 9 November 2011.
The Kooragang Island plant also witnessed a toxic chemical hexavalent chromium leak in August 2011.
The ammonia plant, which manufactures explosives used by the Hunter Valley's mining industry, has been plagued by several more chemical leaks since then.
Orica said that repair work and pre-start testing at its Kooragang Island plant was completed last week.
Site manager Sean Winstone said they have had a number of people on site over the past week, who have continued to work through the pre-start testing.
"I would like to reiterate that we will take as long as is necessary with the restart to ensure that the ammonia plant is started safely," Winstone said.
In December 2011, the company confirmed that there was a contained leakage of 3,000-4,000l of sulphuric acid at its Port Kembla facility on the south coast of New South Wales.
New South Wales Premier Barry O'Farrell said that Orica could lose its licence if it fails to comply with environmental laws.
