Mercury remediation works will begin at Orica’s Botany plant this month after the company received approval from the Environment Protection Authority.
The EPA issued a variation to an Environment Protection Licence which allows remediation work within the Botany Industrial Park, the company said in a statement.
It said it will excavate contaminated soils and construct a vapour cap and barrier walls to bedrock to contain any remaining mercury contamination in the soil.
“Orica is very pleased to be able to commence this important project to address the legacy contamination at the former ChlorAlkali plant within the Botany Industrial Park,” Orica general manager environmental remediation Bill Crowe said.
“The EPA has assessed Orica’s plans and controls that will be used during the work which will now commence.”
The EPA said earlier this year there was no suggestion that the Botany plant’s leak was the cause of contaminated water and local residents’ illness.
Orica told the EPA it had unintentionally leaked 640 litres from its treatment plant the same day locals reported nausea and dizziness due to contaminated water. But the EPA said the two were not related.
“While current testing indicates there are presently no unacceptable human health or environmental risks posed by the mercury contamination at the BIP, Orica understands this is an important issue for the community, and is committed to the remediation works,” the company said.
The company addressed the issue at its AGM.
Orica pled guilty to violating its environmental protection licence last year after a string of spills and safety incidents at its Kooragang Island ammonium nitrate plant.
It was under investigation this year for an ammonia leak at the same plant, after a “plume of ammonia belched into the air from the vent stack of an Orica factory”.
The company was slapped with a $432,000 fine after pleading guilty to charges of unlawful water releases from its Gladstone plant. The fine came after traces of cyanide were found in water samples from a stormwater drain outside the plant.
Remediation work at the Botany plant is expected to take two years to finish.