Hydrogen gas has again ignited at Kooragang Island this weekend following electrical storms.
The flare up is reported to have occurred at around 8pm Sunday night, according to the Newcastle Herald.
The explosives manufacturer stated that there was no risk to the community from the incident.
Sherree Woodroofe, Kooragang Island’s sustainability manager, added that "residents are advised that there is also a chance that other vent stacks may ignite as the start-up process continues".
Orica was last week ordered to report on the latest flare ups at the plant.
The Environmental Protection Authority asked Orica to provide information on what causes the hydrogen gas discharges to ignite during its ammonia plant restart process.
According to Orica’s site manager Sean Winstone, "while it is not part of Orica’s normal start-up procedures, the ignition of hydrogen from a vent stack is not a unique event.
"It has happened in the past both at Orica and at other plants and we have procedures in place to manage it.
"Some plants will deliberately ignite it during the restart process – at Orica we do not deliberately light the gas as part of our standard procedures but the flare poses no risk to the community or to the plant," he added.
The EPA confirmed there was no risk to the community from the flare ups, with chief environmental regulator Mark Gifford stating that "there was absolutely no environmental impact as a result" of the flare ups.
Gifford went on to say that it will have no effect on the plant’s restart process.
"As the flare poses no risk, we have continued with the restart of the Ammonia Plant which has been progressing well," Winstone added.