The US-made plant will “treat” only one megalitre of bore water a day, removing “most” of the PFAS chemicals.

Given that Katherine uses 15 megalitres per day at the peak of demand in a dry season, NT Government officials need the water restrictions from August 21 to reduce this demand down to something like 13 megalitres per day.

Then the authorities can mix the clean water from the new plant with river supplies and the PFAS-bad bore water to provide residents with drinking water under the 0.07 micrograms per litre available limit.

That’s the theory and that’s the reason for the rush.

“Defence has engaged international environmental company Emerging Compounds Treatment Technologies to provide a state-of-the-art water treatment plant that uses a synthetic substance to filter PFAS from water,” Defence Minister Marise Payne said yesterday.

This plant will use a process using Ion Exchange Resins to clean up the PFAS.

It is hoped the add-on will be available from October.

Restrictions will begin in Katherine on August 21.

“This water treatment plant, which is being constructed in the United States, will act as an interim measure that will assist in reducing PFAS concentrations in the bore water component of the Katherine town water supply,” government officials said yesterday.

“The Australian and NT Governments will continue to work closely together to determine the best long-term solutions to ensure that PFAS detections remain below the drinking water health-based guidance values set by Food Safety Australia New Zealand (FSANZ) into the future.

”The identification of new technologies for effective monitoring and management of PFAS contamination is a key priority for Defence,” Ms Payne said.

“Defence continues to engage with industry experts, both nationally and internationally, to identify the best management options for PFAS at its sites.”

Power and Water officials say for Katherine this may mean drilling bores in new locations for the water treatment plant, or a full blow water plant using either the resin technology being trialled, the more popular but expensive activated carbon process or some other solution.