STATE government staff found serious problems with Whitehaven's groundwater modelling at its Maules Creek coal mine but kept farmers in the dark, freedom of information documents have revealed.
The reports, obtained by Maules Creek Community Council, show NSW Department of Industry Water staff found the alluvial aquifer was likely to be draining into the coal seam - not the other way around as assumed by Whitehaven's water model.
The documents also found multiple failings with how the company was self-assessing the water impacts of its operation at Maules Creek.
Maules Creek farmer Rick Laird said Whitehaven's activity was having a devastating impact on landholders in the region.
"At least 13 families clustered around Maules Creek have already had to deepen their bores or put down new ones," Mr Laird said.
"These are bores that have been used in some cases for three generations and they are all within a stone's throw of the mine.
"And yet I sat through a meeting where department staff told me that they couldn't find any problems and Whitehaven was not at all to blame for our bores going dry."
The Department of Industry wouldn't comment on why it left farmers in the dark, other than to point out the state's water watchdog, the Natural Resource Access Regulator, was investigating Whitehaven's groundwater use.
A Whitehaven spokesperson said the FOI documents related to the Maules Creek 2018 Annual Review and updates to the original groundwater modelling had since been made.
"A discrepancy between modelled and observed data is not out of the ordinary for new mines where the accuracy of data and models improves as the mine develops," the spokesperson said.
"There is no credible hydrogeological evidence indicating that bore drawdowns in the Maules Creek area are the result of anything other than the recent lack of rainfall and adequate aquifer recharge for some bores."