A metals manufacturing plant in Port Kembla has been ordered to shut down following tests showing the plant had dioxin emissions over four times the legal limit.
In a statement the NSW Environment Protection Agency said MM had reported the breach after stack emission testing showed emissions from its Horizontal Billet Caster were exceeding the licence limit.
“The EPA has required that MM shut down operation of its HBC, except for controlled start up testing, while the cause of the breach is investigated,” the watchdog said.
“Until the EPA is satisfied that both the cause of the high emissions has been fully identified and rectified, and that MM can operate within the conditions of its Environment Protection Licence the HBC will remain shut down.”
The result for dioxins and furans was recorded at 0.41 nanograms per cubic metre, significantly higher than the 0.1ng/m limit stipulated on MM's licence.
The EPA said it had been advised by the Ministry of Health that the emissions were not high enough to cause immediate health effects, and the potential for long term impacts was unlikely but needed further investigation.
NSW Health is joining the EPA in investigating the breach.