Some residents and at least one councillor in Windsor, N.S., are asking for more transparency surrounding the town's disposal of fracking wastewater.
Town officials said seven million litres of the water went through the town's sewage treatment plant between March 2010 and August 2011.
The water was processed and then pumped into the Minas Basin.
Nova Scotia's Department of Environment approved the disposal, but called it to a halt when it discovered water from the same source contained radioactive elements.
Although the department said the levels posed no real danger, some people are demanding proof.
"First and foremost we have a right to be informed and we were not. We were not informed whatsoever of what was going on and nobody knew anything as far as I can see," said Virginia Taylor with Friends of the Avon River, a salmon-protection group.
Barbara Gallagher with the community group Citizen Action to Protect the Environment agrees.
"I think we ought to see those actual test results, they ought to be made public and I think there should be follow-up testing, just to give people confidence that what we have here is safe," she said.
Town councillor Liz Galbraith said the first time she heard the water contained radioactive elements was on CBC News.
"I would like to know what sort of chemicals we've treated and when the word radioactivity pops up in discussion that makes everybody concerned," she said.
Hydraulic fracturing, or fracking, involves blasting a mixture of water, sand and chemicals into a well bore to split the surrounding rock and release trapped hydrocarbons, usually natural gas, coal bed methane or crude oil.