For the nuclear industry, 2011 was Biblical.

Earthquakes. Tsunamis. Tornadoes. Floods. Fires. 2011 had everything but plagues of locusts.

Since 2001, nuclear critics had been worried about airplanes smashing into plants or dirty bombs. This year nature reminded everyone it can still throw a haymaker, and the reverberations from 2011′s onslaught appear set to dominate US nuclear power in 2012.

March 2011 brought the 9.0 magnitude earthquake off northeastern Japan that sparked a tsunami whose waves may have exceeded 45 feet. Tokyo Electric Power Company’s oldest nuclear station, Fukushima Daiichi, apparently survived the earthquake, but its four oldest reactors didn’t survive that wall of water. Nuclear experts are still figuring out what all went wrong, and tens of thousands still haven’t returned home as Japanese authorities try to decontaminate radioactive hot spots.

In April, massive tornadoes that devastated the southeast swept near the Tennessee Valley Authority’s Browns Ferry plant.

In June, droughts sparked wildfires across the Southwest, including one that threatened the Los Alamos National Laboratory, where nuclear weapons materials are stored.

June also brought record floods across the upper Midwest. For weeks Omaha Public Power District’s Fort Calhoun nuclear plant was essentially an island.

August saw the 5.8 magnitude Virginia earthquake just 11 miles from Dominion Energy’s North Anna plant. The plant shut safely, and returned to service mid-November after extensive checks found no damage even though ground motion briefly exceeded the plant’s design.

Aging Generation Giants

All these challenges resurrected questions about the robustness of America’s nuclear fleet as reactors begin to pass the 40-year mark. That was once considered the operating limit, but with safety backfits, regular material checks and planned component replacements, the Nuclear Regulatory Commission says reactors can operate for 60 years. More than half of the 104 reactors in the US have been licensed to do so.

We cannot afford to proceed in a ‘business as usual’ manner … nothing was usual about 2011 – Jaczko

Both regulators and the industry’s safety organization, the Institute of Nuclear Power Operations, began within days of Fukushima to assess whether similar threats could happen here. Walkdowns of plants seeking undetected quake and flooding risks were under way within two weeks, said Nuclear Energy Institute CEO Marvin Fertel.

By June, NRC’s Fukushima task force came up with a dozen regulatory recommendations, ranging from improving plants’ capability to cope with extended station blackouts and to overhauling the patchwork of agency rules created over 30 years. NRC has several years of work planned to put those recommendations into rules.

Seeking Silver Linings

But the events brought some good news, said both Fertel and Union of Concerned Scientists nuclear expert David Lochbaum, a frequent industry critic. Measures taken by US plants to deal with terrorism after 9/11, like stationing portable pumps on site, could also help cope with natural disasters, they said.

Another positive: neither Fort Calhoun’s flooding nor North Anna’s quake came as a surprise. Fort Calhoun’s flood defenses were raised in 2010 after NRC required improvements to meet a revised flood threat assessment, Lochbaum noted, and NRC was already working on a finding that North Anna and some other East Coast plants could experience more severe quakes than predicted when they were built.

The big surprises, Lochbaum said, were the hydrogen explosions and the power blackout disabling all four reactors at Fukushima at once. Hydrogen exploded at Three Mile Island-2, and Lochbaum said most people thought NRC rules had solved the issue. Now, it’s open again. And NRC rules have assumed only one reactor at a multi-unit site would lose power at any given time. Lochbaum said Fukushima proved that assumption doesn’t hold.

Fertel said the industry and NRC are “in very good alignment” on the issues raised by 2011 events. The concern for utilities is the “cumulative impact” of new rules, he said, and making sure they’re ranked so plant staffs attack those with the most safety benefit first and the cost is manageable.

“We cannot afford to proceed in a ‘business as usual’ manner … nothing was usual about 2011,” NRC Chairman Gregory Jaczko warned industry leaders November 10.

Lochbaum said he has found “most” people in the industry recognize the need to take 2011′s warnings seriously. “They don’t want to be the next Fukushima,” he said. “No one wants to lose a billion dollar asset.” He agrees time is needed to get the fixes right, but cautions, “You can’t take forever.”