With Australian Pesticides and Veterinary Medicines Authority approval for the use of bromadiolone around crops still pending, Mr Marshall said the government doubled the number of sites initially suggested for the baiting program.

Along with Dubbo, Forbes and Mudgee, should approval be granted sites will also be set up at other western NSW areas including Nyngan, Condobolin, Coonabarabran and Coonamble, while Merriwa and Walgett are also on the list.

Mr Marshall also confirmed Gunnedah, Holbrook, Inverell, Jerilderie, Moree, Narrabri, Narrandera, Scone, Tamworth, Wagga Wagga and Warialda as the other areas where sites will be established.

Perimeter baiting with bromadiolone, used in combination with zinc phosphide, will create a multi-layered defense of farmers' crops, he said.

"Instead of the initially suggested eight to 10 sites, we've now made our grain treatment even easier for farmers to access and doubled that number to 20," Mr Marshall said.

"These mice are a scourge on our regional communities, but these 20 sites will be strategically located throughout the state's most affected areas, from Warialda to Jerilderie, and Condobolin to Scone, to help ease the burden.

"When I'm on the ground talking to farmers, they tell me they need additional weapons against this pest and bromadiolone will help achieve that alongside zinc phosphide.

"As for when our treatment stations will be up and running, well that is entirely up to APVMA approval - we are in close contact with them ... to ensure all safety and environmental considerations are addressed but once they give us the green light then we'll be ready to roll in a matter of days.

"We have already secured 5,000 locally-sourced litres of bromadiolone, with an additional 5,000 litres arriving from overseas in the coming days, so our certified staff will be ready to start treating grain completely free of charge for farmers."

Farmers can register for grain treatment through their nearest Local Land Service office, with sites to operate in rotation and by appointment to ensure safe chemical handling and access for staff and customers.

Mr Marshall said the treatment sites would complement the measures already put in place by the NSW Government to support landholders.

"Our workshops educating farmers on best practice to manage mice continue to be well subscribed and well received," Mr Marshall said.

To best manage any potential risks posed to non-target species, bromadiolone will only be handled by LLS experts. Landholders will also be educated on best practice and will need to adhere to strict APVMA guidelines when handling treated grain.

The free grain treatment is part of the NSW Government's $50 million support package to manage the impacts on regional communities, which also includes bait rebates for households and small businesses, community workshops and targeted pest research.

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