The Greens are calling for a ban on antimony mining on the Dorrigo Plateau, after another heavy metal spill.
The Department of Environment says a stormwater dam at the old Hillgrove mine near Armidale overflowed into the Macleay River last weekend. Last month, the Environmental Protection Authority imposed new regulations to try to stop spills from the mine, which has been bought by mining company Ancoa.
Greens' MP Jeremy Buckingham says the New South Wales Government should stop Ancoa reopening the mine.
"The Dorrigo Plateau feeds a couple of NSW most important rivers, the Macleay and the Clarence," he said.
"Any antimony mining on that plateau is unsafe.
"We want the Government to rule this area out for mining and protect our precious water resources.
The Environment Department says Macleay River water quality is unlikely to be affected, despite the mine spill. However, Mr Buckingham says the Government should ban antimony mining on the Dorrigo Plateau.
"These spills should not be allowed to continue," he said.
"For the people that rely on that river for their drinking water, for agriculture, for irrigation, any spill is one spill too many.
"The assurances from the various departments, that these spills are minor and will be diluted doesn't carry any weight with these communities."
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