For the people who want to shut down a nuclear plant in the New York City suburbs, where 17 million people live within 50 miles, this day has been a long time coming.

Five years after the owner of Indian Point applied for licenses that would keep it running for 20 more years, federal hearings on the application begin on Monday.

It could be a few more years before a final decision, but blocking the licenses has long been the focus of the environmentalists and politicians — including Gov. Andrew Cuomo — who have campaigned against the plant, on the Hudson River in Buchanan, 35 miles north of Manhattan.

Anxiety climbed after the 9/11 attack in 2001, when one of the hijacked planes flew right over the nuclear plant on its way to the World Trade Center, and again after the 2011 quake-and-tsunami nuclear disaster in Japan.

Opponents have argued that the threat of terror or accident is too great at a nuclear plant so close to the nation’s largest city.

“My point has always been safety first, and the reward doesn’t justify the risk,” Cuomo said last year.

The Nuclear Regulatory Commission has found repeatedly that Indian Point operates safely, and its staff has issued reports favoring the license application.

But the state and two environmental groups are challenging renewals on 10 grounds. First up on Monday before a panel of three judges is whether corrosion in pipes and elsewhere can be safely managed for 20 more years.

Other issues include decontamination after an accident, the cost of human exposure to radiation, property values, and leaks from the spent fuel pool.

Not on the agenda are plant security and the difficulty of evacuating such a densely populated area — “the issues people really care about,” says Phillip Musegaas, a program director at the environmental group Riverkeeper. The NRC says those topics are continually studied and are not germane to relicensing.

Nevertheless, the challengers have high hopes, although the NRC has never refused a plant’s renewal license.

“I think this really spells the end of Indian Point,” said Robert F. Kennedy, chief prosecuting attorney for Riverkeeper, one of the groups challenging the licenses. “The noose is closing.”

Plant owner Entergy Nuclear is confident the licenses will be approved.

“These are issues that we’re pleased to have a chance to discuss in this administrative setting,” said spokesman Jerry Nappi. “We feel we have a sound technical basis on each issue.”

Besides Indian Point, eight other plants with 11 reactors are currently seeking renewals. They include the Davis-Besse plant near Toledo, Ohio, which was shut down for two years because of what the NRC called the most extensive corrosion ever found at a U.S. nuclear reactor.

Last year, the NRC approved a new license for the Vermont Yankee plant in Vernon, also owned by Entergy. The state tried to shut it down, but a federal judge ruled for the company. Vermont is appealing.

The two reactors at issue in New York — Indian Point 2 and Indian Point 3 (Indian Point 1 was mothballed in the 1970s) — have 30-year licenses that expire in 2013 and 2015, respectively. But both sides agree that the first date, and possibly the second, will come and go before the new licenses are settled.

That’s because these hearings will stretch into next year, judges usually take months to rule, appeals are inevitable and the NRC declared in June that it will make no final decisions on licenses until after a two-year study of its nuclear waste rules.

“You can just do the math and see that this is not going to be a matter of months,” said NRC spokesman Neil Sheehan.

Musegaas said, “We hold no illusions about closing Indian Point in 2013. To us this is the beginning of the end of a long process.”

No matter how long it takes, under NRC regulations, Indian Point can keep running until there’s a final decision, expired licenses or not.

The plant’s opponents have a kind of ace in the hole unrelated to the federal hearings. The state has denied Indian Point a water quality permit, saying that by drawing in Hudson River water for cooling, it kills billions of fish and eggs.

Although nuclear plants are regulated by the federal government, not the states, the NRC has said it cannot issue a new license unless Indian Point has the water permit. Entergy says the alternative, building cooling towers, would cost it $1.5 billion. It is appealing the state decision.

The potential closing of Indian Point, which provides about a quarter of the power used in New York City and Westchester County, has fostered a succession of studies on how its 2,000 megawatts would be replaced.

The industry warns of brownouts, pollution, job cuts and higher electric bills. Environmentalists see an opportunity for turning to renewable sources. Cuomo said, “We can retrofit old plants, we can site new plants, we can improve transmission lines. So if we want to find replacement power, we can.”

(AP)