– The United States is set to become the first nation to decide whether it’s safe to operate nuclear power plants for 80 years, twice as long as initially allowed.

The majority of the nation’s 99 reactors have already received 20-year extensions to their original 40-year operating licenses. Now, operators led by Dominion Resources want to expand the time frame further, potentially creating a precedent for an aging global fleet at a time when the economics of the industry are undergoing dramatic change.

Dominion said earlier this month it will request an extension from the U.S. Nuclear Regulatory Commission, which oversees the industry. The plan already has raised the ire of anti-nuclear campaigners who cite decades of wear and tear on the nation’s reactors, as well as the 2011 Fukushima disaster in Japan. The NRC will release a draft in December outlining safety measures needed to extend the time line.

“The reality of life is the risks go up” as plants age, said Dave Lochbaum, director of the nuclear safety project for the Union of Concerned Scientists. “If you don’t respond with more aggressive risk management, then you’re inviting disaster.”

An approval may determine the fate of the world’s oldest nuclear fleet, one that’s being battered by high operating costs, expensive safety upgrades and an abundance of cheap natural gas that’s squeezing profits. If allowed, Dominion’s Surry plant in Virginia would be the first to outlive the average human in the U.S. with a life span of 78.8 years. A final decision won’t come before the early part of the next decade.

“We are at the forefront,” said Tina Taylor, a director at the Electric Power Research Institute Inc. “As we demonstrate extending the licenses of plants and continue operating them, it sets a model for how people will do that around the world.”

Global nuclear retirements of as much as 144 gigawatts are expected by 2030, about 38 percent of current capacity, according to the International Atomic Energy Agency.

Utilities are seeking extensions as some reactors shut early, unable to compete with the shale boom that’s flooded the market with abundant supplies of natural gas. About 10 percent of U.S. nuclear output may be retired early, according to Moody’s Investors Service. Five reactors have been closed in the last three years, and three more are due to shut down by 2019.

The U.S. is the first country to set out a path for reactors to run to 80 years, said Tom Kauffman, a spokesman for the Nuclear Energy Institute, an industry advocacy group.

“There are a number of safety issues with pushing these technologies twice beyond their original projected life span,” said Tyson Slocum, director of energy at Public Citizen. “You’ve seen a number of issues from Davis-Besse to Vermont Yankee where aging components triggered a variety of leaks.”

The thinning of the U.S. fleet will hamper government efforts to tackle climate change, industry supporters say, since atomic power provided 63 percent of all carbon-free electricity in the U.S. in 2014.