HALIFAX -- A coalition of environmental groups opposed to hydraulic fracturing in Nova Scotia says legislation that would ban the practice is seriously flawed.

The group had initially applauded the province's Liberal government when it announced a renewed moratorium last month through amendments to the Petroleum Resources Act.

But the Nova Scotia Fracking Resource and Action Coalition said Monday a closer review of a bill tabled last week has revealed shortcomings when it comes to a definition for fracking, community consent and exemptions for research.

Gretchen Fitzgerald of the Sierra Club said by defining fracking in regulations rather than in the bill, the government is allowing the energy minister to make changes without public debate or a vote in the legislature.

"The definition of hydraulic fracturing covered by the bill determines the extent of the ban," the coalition said in a statement. "The definition should be in the bill itself."

But Energy Minister Andrew Younger said that's not the case, adding that the province's staff and lawyers have told him the appropriate place for the definition is in the regulations under the province's Petroleum Resources Act.

"The definition under the Petroleum Resources Act will tend to be a very highly technical definition and that's not the sort of thing you put in legislation," said Younger. "The definition can't be weakened to the point of being in violation of the act.

"The bill prohibits high-volume hydraulic fracturing in shale formations. You can't then pass a regulation that would allow it."

The coalition also said the bill does not include a requirement for community consent before fracking is permitted, which was a key recommendation from an expert panel review done for the government.

But Younger said any regulatory changes require a 30-day public comment period.

"There is public input. It is a public process," he said.

As well, the coalition is critical of the bill because it's specifically aimed at high-volume hydraulic fracturing in shale rock formations.

Coalition member Mark Tipperman said that creates a loophole for companies hoping to frack for oil or gas in different types of sand or rock.

"Unconventional gas and oil development occurs not just in shale formations but also in tight sands and coal beds," the coalition says. "The risks arising from fracking in these other formations are similar, if not identical, to fracking shale."

Younger said the process has always been limited to shale formations since it was started by the province's previous NDP government three years ago.