SPRING CITY, Tenn. - In a building off to the side of Watts Bar Nuclear Plant, TVA's nuclear operators have been playing "what if" for the last month.
What if a very large earthquake occurred? What if the quake caused a dam break? What if more than one reactor lost cooling power?
On Monday, as reporters waited to hear Sen. Lamar Alexander, R.-Tenn., report on what he and Nuclear Regulatory Commissioner Bill Ostendorff saw on a tour of the plant that morning, three operators in a control room simulator responded to a mock earthquake and electric power loss for cooling to the reactor.
Bells and alarms sounded, light flashed, and the trio of operators jumped to action.
Even before an 9.0 earthquake in March dismantled the electrical power system to the six Japanese reactors and a tsunami swept away the fuel for the plant's back-up diesel generators, U.S. nuclear plant operators drilled for 240 hours a year in this and similar training rooms across the U.S.
But since the accident at the Fukushima Dai-ichi plant in Japan, the U.S. simulators also have become testing grounds of "stacked" disasters.
"The trainers are like Satans. They just keep on injecting failures upon failures on these poor operators," said Ray Golden, TVA's nuclear spokesman.
After his tour, Alexander gave the plant and nuclear power glowing praise, adding that he and Ostendorff saw a "whole variety of backup ways" to deal with any loss of power and cooling such as what plagued the Japan plant.
He also used his time with reporters to tout the safety of storing spent nuclear fuel at the plant sites and to talk about what he sees as an opportunity to recycle the spent fuel.
"I favor investing in new research which is being done in Oak Ridge and other places to find ways to recycle and reuse nuclear fuel in a way that will reduce the mass and permit it to be reused over and over and over again," Alexander said.
Recycling nuclear fuel, sometimes called reprocessing, already is done in France and some other countries but is not allowed in the U.S. Critics say it is a nuclear proliferation risk and creates more waste.
"I'm here today because it's very important, especially for those of us who believe nuclear power is important part of our region's and country's future, to make sure our plants are being operated as safely as possible, especially after the Japan incident," Alexander said.
Ostendorff, a former nuclear submarine commander, used the word "impressive" to describe the Watts Bar maintenance work he saw Monday during a refueling outage.
He and Alexander said nuclear power has an enviable record. There has never been a fatality in connection with any of the 104 reactors in America, or with the many nuclear reactors on U.S. Navy ships.
"Three Mile Island was our most celebrated nuclear accident in the United States, and no one was hurt," Alexander said.
Nuclear power is about 30 percent of TVA's power generation mix, and it is about 80 percent of what Alexander termed "clean" electricity.
"By 'clean' I mean no air pollution from sulfur, nitrogen or mercury," he said. "That's important to our health. It helps attract tourists. It's important to Volkswagen as it tries to attract suppliers to East Tennessee.
As for the "what ifs" rehearsed in the simulator control rooms of Watts Bar and other TVA nuclear operators, the exercise already is prompting change, said John Dalton, TVA's Watts Bar operations training manager.
The utility will be toughening up the electrical power "switchyard" to Watts Bar to further protect it against seismic events. TVA officials told the utility's board of directors of the plan last week, along with new plans to add additional diesel generators, portable generators and satellite phones.
Contact Pam Sohn at firstname.lastname@example.org or 423-757-6346.