The Northern Territory Government says it will speak to mining company ERA and the office of the Commonwealth Supervising Scientist about contaminated water leaking from the Ranger Uranium Mine.

About 100,000 litres of contaminated water is seeping from a tailings dam at the mine every day.

Environmentalists are calling for the mine's planned expansion to be put on hold.

The Office of the Supervising Scientist and ERA say the water is not seeping into Kakadu and there is no reason for concern.

NT Resources Minister Kon Vatskalis says he is concerned, but the mine is well monitored.

"The Ranger Uranium Mine is one of the most strictly regulated uranium mines in Australia and the Office of the Supervising Scientist is controlling, is supervising, very strictly the mine," he said.

"I'm prepared to talk with the Office of the Supervising Scientist to find out exactly what's happening, why it's happening and how the scientists and the company are going to address this issue," he said.