OTTAWA — The federal government has given approval in principle for the underground disposal of nuclear waste, long a contentious issue for environmentalists.

But Natural Resources Minister Gary Lunn says it will take years of consultations to choose a site, and decades to actually deposit the waste.

"This is just the beginning of quite a long process. It will be a number of years before there is anything further to announce," Lunn said Thursday outside the House of Commons.

The minister said the cost of building a waste facility would be in the billions of dollars, but insisted the nuclear industry would foot the bill. Nuclear operators are required to set aside money for storage, and Lunn said there is already $1 billion in the fund.

Many environmentalists oppose underground storage because of concern about radioactive leaks or accidents.

"Deep geological storage is delayed pollution," said Shawn-Patrick Stensil of Greenpeace. "This material needs to be isolated for a million years."

He questioned the government's assumption that it can find a willing community to accept the waste facility, saying the proposal will create social conflict for years to come. Stensil said the solution is to stop producing the waste.

Lunn said he believes a willing community can be found through extensive consultation. He added that the waste would be retrievable so as to allow for the possibility in the future of reusing spent fuel. There's no intention to accept waste from other countries.

There has been renewed interest in nuclear energy as an alternative to fossil fuels that contribute to global warming, but environmentalists say the focus should be on renewable energy and energy efficiency.

The federal government has been trying for years to come up with a long-term plan for managing nuclear waste. The lack of such a plan has been seen as a major impediment to expansion of the nuclear industry.

Lunn denied there is any connection between the two issues. Any decision about new plants must be made by the provinces, he said.

The Canadian Nuclear Association welcomed Lunn's decision.

"I am pleased that the government is moving ahead with the plan which features centralized containment and isolation of used nuclear fuel in a deep geological repository with the option of a shallow underground storage facility while the repository is being developed," said Murray Elston, president and CEO of the association.

"We favour the phased management approach because it is based on good science and good technological research and is consistent with the path taken by France, the United Kingdom, Finland, Sweden, Japan and the United States."