Regis has also looked at taking water from shallow water aquifers near the mine site west of Bathurst, conducted extensive searches for deep water aquifers in the area and also commenced negotiations with State Water and Centennial Coal about accessing waste water from coal operations in the Lithgow area.

But development manager Rod Smith said a deal with Bathurst remained Regis’ favoured option due to the proximity of the water source and the fact the company believes buying the treated effluent would be the most environmentally-friendly option.

Bathurst Regional Council is considering a proposal from Regis Resources to buy between eight and 10 megalitres of treated effluent a day to run its proposed McPhillamys mine at Kings Plains.

Submissions from the public will be received until 5pm on Monday.

The proposed purchase is equivalent to the total daily output from the Waste Water Treatment Works back into the Macquarie River and the plan has angered local conservationists and downstream river users. They say taking the treated effluent from the river would further reduce flows and endanger fish breeding grounds.

But Mr Smith said while local people had every right to raise concerns about the proposal, each of their fears had been addressed by the company.

Mr Smith said independent reports from SKM and GHD Australia commissioned by council had determined it was feasible to divert the effluent without damaging the river system so long as “cease to transfer” rules were in place.

The cease to transfer rules would come into play once river flows dropped below an agreed level [recommended as 4.1 megalitres per day in the SKM report] and would require Regis to stop pumping water to its mine.

Mr Smith said recent data showed river flows dropped below that level an average of five days a year, and Regis would build a large water storage at the Kings Plains site to continue operating on those days.

“We have also done baseline fauna and flora studies in the area and there have been no species identified that are endangered to the point that they would represent a fatal flaw in the project,” Mr Smith said.

Mr Smith said the mine would use, in total, about 17 megalitres of water a day but 60 per cent would be recycled to limit the amount it needed to divert from the river.

Regis is yet to finalise a route for the proposed pipeline, though Mr Smith said there was already an easement in place between Lithgow and Orange for a gas pipeline and the Regis pipeline would likely follow a similar path.

“It would be an underground pipeline for almost all of the route, though it might end up above ground in places like Fitzgeralds Mount where you would do more damage to the environment by putting it underground,” he said.

If council accepts a deal to sell the region’s treated effluent to Regis, the company would then commission an environmental impact statement as part of its application to develop the mine.

If all approvals for the mine are granted, mine construction would take 12-18 months and Regis would hope to begin operation in mid to late-2018.