A company that wants to frack for oil close to Calgary city limits is facing opposition from nearby residents who fear the project will poison their tap water.

Bernum Petroleum has applied to use the controversial method — which involves blasting a mixture of water and chemicals into the ground to release trapped oil or gas — at a site near Calgary’s biggest source of drinking water.

Joan Gusa, whose family farms land on the city’s northwest outskirts, worries about the drilling’s possible effects.

"With all of the problems recently that have come out about fracking and how it has contaminated the water wells ... that is a concern," she said.

Fracking has been banned in parts of the US, Europe and in Quebec over environmental concerns.

Water scientist David Schindler agrees the proposal to drill a well just three kilometres from the Bearspaw Reservoir is a cause for concern.

"It’s very controversial and I am surprised that the Alberta government has not put a halt on it until more research has been done."

Schindler says not enough is known about the impact of increased fracking on ground and surface water.

"There are suggestions coming in from competent scientists around the world that what is going on has a big environmental downside," he said.

But according to Bob Curran, who speaks for Alberta's Energy Resource Conservation Board (ERCB), the province has strict regulations around fracking.

And so far the drilling method has not caused any environmental problems in Alberta, he said.

"You are not allowed to fracture a well within a certain proximity to groundwater and from what I understand these wells are quite deep and it is very unlikely that they would be within any proximity to ground water at all," Curran said.

Marshall Abbott , the CEO of Burnam Petroleum, said the wells will be more than 2,000 metres deep and completely safe.

"There is not enough energy in these fracks to penetrate more than 60 metres of rock. And we can tell that through the advanced seismic techniques we employ," Abbott said.

Burnam's application is currently before the ERCB, which is also reviewing Alberta's fracking guidelines.