They have engaged law firm Holding Redlich to approach the ARTC, highlighting in particular concerns relating to the ARTC's hydrology modelling.

NSW Farmers' Inland Rail Taskforce chair, Adrian Lyons said they have tried to negotiate with the ARTC for the past four years but the conversations have not been transparent.

"We're saying... come to the table and stop talking in platitudes where we don't get any information," he said.

"Through sending legal correspondence to the ARTC, we have clearly outlined the main concerns facing landholders along the proposed rail route,"

They want the ARTC to fund an independent hydrologist, of their choosing, to look at the modelling and go through what has happened on the Narrabri to Narromine section.

A hydrologist is a specialist who analyses the quantity and quality of water in rivers, lakes, storm water and sewerage.

"We don't trust their capacity to engage hydrologists that are able to do what we need to find out," Mr Lyons said.

"We will choose the independent hydrologist of the ARTC to review their hydrology modelling but at the same time we have a lot of unanswered questions. We want to know what the compensation measures are, how much there is. "

Mr Lyons said it is critical that if the ARTC are going to traverse through that section they need to justify it but also have local input from farmers whose properties the track will go through.

"If people are going to accept this line they want to know how much they're going to be paid if they split their farm in half. We don't now that, or how many bridges, overpasses or crossings (there will be)."

NSW Farmers have told their members whose properties are affected by the track not to engage with the ARTC.

"We ask them to get legal representation and then move forward. They need to have a legal body who understands how the ARTC works," Mr Lyons explained.

But the ARTC's CEO Richard Wankmuller said they have not only engaged regularly with NSW Farmers, but farmers and landholders too.

"We recognise that NSW Farmers has an important role in Inland Rail which is why I have engaged with them genuinely and consistently over the past two years," he said.

"ARTC has met with NSW Farmers has had productive engagement going back to early 2018.

"We were able to come to agreement on land access protocols and principles and we have published the answers to all their questions in the past."

Mr Wankmuller said working with farmers is the best way for the ARTC to ensure that they can mitigate their impacts and deliver Inland Rail to the highest standards.

"We have met with over 100 of the farmers and landowners that we are working with collaboratively to deliver Inland Rail between Narromine and Narrabri in the past couple of months," he said.

"Those are productive meetings, that will ensure that we can build Inland Rail to the highest standards while mitigating the impacts on those farmers."

ACM put forward a question to the ARTC if they would fund an independent hydrologist, chosen by NSW Farmers, to review the hydrology modelling, but they did not respond.

CWA of NSW CEO, Danica Leys said in taking legal action the CWA and NSW Farmers hope to develop a collective of landholders and community members who want to progress advocacy around Inland Rail.

"We encourage affected landholders to register their interest in joining ongoing advocacy efforts," Ms Leys said.

"Currently, our legal correspondence is focused on the Narromine to Narrabri stretch of the rail route, but our aim is that any positive developments would be mirrored in other parts of the infrastructure."

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