The provincial Environment Department issued a statement Monday saying the advisory applies to the Town of South Brook, where the 500 residents are also being told they can't use the water for cooking, washing food, brushing teeth or making juices, baby formula and ice.
However, officials said it's safe to use the water, which comes from the South Brook River, for bathing, washing clothes and dishes.
The department did not say when the dam ruptured or what kind of tailings it contains.
"No contaminants have actually been found in the town's drinking water supply," spokeswoman Melony O'Neill said in an email.
"Samples are being taken ... and will be conducted on an ongoing basis. As a precautionary measure, a non-consumption drinking water advisory was issued."
The tailings are from the former Gullbridge mine site, which produced copper in the late 1960s and early 1970s, according to the Geological Survey of Canada.
South Brook's water supply is about 20 kilometres downstream from the Gullbridge dam.
The town is on the Trans-Canada Highway, halfway between Deer Lake and Grand Falls-Windsor.