DURALIE open-cut coalmine near Gloucester has applied for permission to pump as much as 500 million litres of mine water into the nearby Mammy Johnsons River.
The application, confirmed yesterday by the NSW Department of Environment and Climate Change, has been lodged because a dam on the mine site is full to overflowing and excess water can no longer be distributed by irrigation.
The department's Newcastle manager, Grahame Clarke, said Gloucester Coal had applied to pump up to 500 megalitres over two years directly into Mammy Johnsons River, a tributary of the Karuah River.
Mr Clarke said a licence variation that did not breach the mine's operating conditions could be dealt with by his department, otherwise it would be referred to the Department of Planning.
The plan has angered some residents and the environmental movement, which points out that the State Government approved Duralie as "a no-discharge mine".
Greens MLC Lee Rhiannon said the State Government should shut the mine until the water problem was sorted out.
She quoted a July 2006 statement by Planning Minister Frank Sartor, who said that "preventing any discharge to local waterways" was a key condition of consent.
Gloucester farmer and Duralie consultative committee member Doyne Lanham said the water problem had dogged the mine for some time.
He said mine planners believed there was less than a 1 per cent chance of the 1400-megalitre "dirty water" dam overflowing during the life of the mine.
But with the drought broken, the dam was full and with coal the price it was the company did not want to use its back-up plan of storing the water in the mine pit.