'Concerning' lack of transparency over toxic pollution

Pollutant levels at the Ichthys LNG facility are below regulatory standards, operator Inpex says.

Darwin residents have been kept in the dark for more than a year about elevated levels of cancer-causing chemicals being emitted into the air at a nearby gas processing plant.

Although its Ichthys LNG facility is emitting eight times more volatile organic compounds (VOCs) per year than initially promised, Japanese oil and gas giant Inpex says there is no cause for concern over public safety.

Inpex senior vice-president Bill Townsend told a parliamentary inquiry that acid gas incinerators at the plant, which burn off toxic pollutants such as benzene, had been off intermittently for more than a year.

Despite this, the community has not been informed.

Greens senator Sarah Hanson-Young was concerned that it demonstrated a lack of transparency from Inpex, which has exacerbated community fears about further development in Darwin Harbour.

"The reason for that is that what the community would know, and what they should know, is that we monitor the air quality, and all of that is within limits," Mr Townsend told the Senate hearing on Tuesday.

The plant, which is 4km from central Darwin, was operating safely and pollutant levels were below regulatory standards, he said.

While planning documents for the project estimated it would emit 500 tonnes of VOCs such as benzene per year, in 2022/23 it emitted 3900 tonnes of VOCs.

But monitoring by Inpex and the Northern Territory environment regulator found benzene levels in the air were below detectable measures, meaning they would be well below the maximum allowable limit of three parts per billion.

Mr Townsend said the incinerators would be brought back online imminently, one of them perhaps as soon as the end of the week.

Inpex was being grilled as part of an inquiry into a gas processing and manufacturing project next door to the Ichthys site at Middle Arm.

While Inpex is not a part of the new development, its Bonaparte carbon capture and storage project stands to benefit from the added gas production it will enable.

Inpex plans to inject hundreds of millions of tonnes of CO2 generated by its own and other companies' facilities under the sea bed off Darwin.

Australian Conservation Foundation program manager Gavan McFadzean called the technology "completely fanciful" and not cost-effective.

"We would argue that this project going ahead, reliant on economically implausible and we think technologically unfeasible technology, and with a hope and a prayer that Australia will still stay within its emissions reduction targets, is extremely high risk," he said.

Mr Townsend called this fake news.

"Carbon capture and storage has been in place for a long time. There's more than 40 projects under way at the moment," he said.

"This is proven technology and it's essential if the world is serious about getting to net zero by 2050."