MONTREAL - Energy companies will be required to receive an authorization certificate before they can drill for shale gas, Quebec's environment minister confirmed Monday.

The permits, which aim to protect drinking water, come after the government acknowledged irregularities at three small-scale test wells in Becancour, near Trois Rivieres.

A risk of contamination was identified at one site, and another well was found to be leaking natural gas into the atmosphere.

"There were a few problems in the way it was drilled and so they decided to act," said Environment Minister Pierre Arcand.

With close to 30 wells drilled along the length of the St. Lawrence River, companies have so far been authorized by the Ministry of Natural Resources, but not the Ministry of the Environment.

"It's a brand new industry, and… I have been appointed about a month and a half ago and I'm looking at the situation and I'm adapting now to those rules," said Environment Minister Pierre Arcand, who said his inspectors will now be paying surprise visits to those companies performing exploratory drilling.

""(We'll) make sure that they know exactly how much water is being used, and what is being used, what additives we put in the water," he said.

The new rules come after concern about the drilling process and its effect on groundwater.

Shale gas is extracted by blasting the surrounding rock with sand, chemicals and water.

The move came the same day public hearings began on the environmental impact of shale gas exploration. The first session of hearings run from Monday until Wednesday or Thursday, depending on the number of speakers.

Quebec's Oil and Gas Association held heated public information sessions last month. Quebecers have been outspoken with concerns about potential environmental impact, like the contamination of drinking water and possible pipeline problems.

Parti Quebecois environment critic Martine Ouellet said despite the new permits, the Liberals aren't working hard enough to protect the environment.

"It's too little, too late," she said. "We're for the shale gas exploitation but not at any price and any consequence for the environment."

Head of gas association to miss start of hearings

Andre Caille is being forced, because of illness, to sit out under doctor's orders as environmental hearings begin.

Caille, head of Quebec Oil and Gas Association, has been at the centre of the stormy debate.

A former head of Hydro-Quebec, Caille had organized three public hearings on shale gas that were particularly raucous affairs. He left one meeting out of concern for his own safety, and police escorted protesters away.

Caille will miss the first two weeks of the environmental hearings.

With files from The Canadian Press