30 March 2011

Three Mile Island Haunts US Nuclear Policy

32 Years Later, Industry Still Recovering From Its Worst US Nuclear Disaster

At about dawn on March 28, 1979, Pete Velez was cruising through Middletown, Pa., past the Blue Room saloon where some of the guys from work drank after their shifts.
Velez was headed to work at Three Mile Island nuclear plant, where four 370-foot cooling towers stood proudly over the countryside, signs of a new age of technological progress, according to the 1982 book "The Warning -- Accident At Three Mile Island," by Mike Gray and Ira Rosen, an inside account of America's worst nuclear accident.
The book describes how Velez arrived to find cars backed up and figured it must be a security issue -- maybe someone left a door open. He chatted with the gate guard.
"What's the matter, you lose somebody?" Velez smiled.
"Well, what's going on?"
"Radiation emergency."
"A drill? At 6 o'clock in the morning?"
"It's no drill."
As radiation-protection foreman, Valez's job was to make sure no one was unnecessarily exposed. Fueled by adrenaline, he raced up stairs to the Unit Two control room and threw open the door to startling chaos. Packs of engineers, technicians and plant managers were huddled in the cavernous room, all talking over each other. The 90-foot long arching wall of lights and gauges, along with a shorter console that followed the same arc, were lit up like Christmas trees. Radiation alarms went off one after another, jangling the nerves of the trouble-shooters.
Velez carried a little green notebook for scribbling notes about anything that he thought might be important. At that moment he simply wrote, "Aw [expletive]."
It's been more than three decades since the worst nuclear plant crisis in the nation's history, and U.S. nuclear plants have boasted a mostly spotless safety record since then. But anxiety over radiation leaks at the crippled Fukushima nuclear plant in Japan have have again renewed fear over nuclear plant safety.
Ultimately, it was deemed that the Three Mile Island accident was caused by faulty equipment and bad decisions made amid chaos -- "a combination of personnel error, design deficiencies, and component failures," as the Nuclear Regulatory Commission summed it up.
Investigations and cleanup revealed that the core of the plant partially melted down, unbeknownst to the harried officials working feverishly inside the plant at the time. The plant was dangerously close to a total meltdown -- a full-scale national disaster.
Remarkably, most of the radioactivity released by the partial meltdown was contained inside the plant and it resulted in no long-term health effects or environmental damage, most experts agree.
But five days of panic in Pennsylvania left lasting legacies. Three Mile Island became synonymous with nuclear catastrophe, stoked public fear of nuclear power, led to an overhaul of plant safety rules and effectively drained the steam from an entire industry – no new nuclear plants were ordered for 28 years.
Three Mile Island "remains the single most important event in the fifty-year history of nuclear power regulation in the United States," leading Three Mile Island expert J. Samuel Walker, says in his 2004 book "Three Mile Island – A Nuclear Crisis In Historical Perspective."

What Went Wrong

Nuclear power plants generate energy by boiling water into steam that turns turbines, which produce electricity. To generate steam, nuclear plants use heat from fission – the splitting of atoms of uranium fuel. More than 36,000 zirconium alloy rods packed with about 100 tons of uranium pellets were bundled and placed inside the reactor core.
The chaos that Velez found when he arrived at work was set in motion inside Unit Two at about 4 a.m.
Media reports and books that chronicle the inside story of the crisis – including reports by PBS, in the Washington Post and the books by Walker, Gray and Rosen, and "TMI: 25 Years Later" by Bonnie Osif, Anthony Baratta and Thomas Conkling -- explain how it unfolded.
Pumps that move water through the reactor failed, prompting the plant's massive steam-powered turbines and the reactor itself to shut down.
When heat and pressure inside the reactor increased, a relief valve popped open. But the valve malfunctioned and did not automatically close when the pressure decreased.
Cooling water flowed out of the valve, and that led to partial meltdown – the zirconium rods failed and uranium pellets melted, releasing highly radioactive vapor, some of which was vented into the atmosphere in the following hours.

Communications Fail Amid Chaos

Plant managers and technicians tried to diagnose the fast-multiplying problems as instruments showed conflicting information about the temperature and pressure in the core. Radiation meters started clicking and officials at times were awkwardly communicating through respirators. They missed clues that would have tipped them to the source of the trouble. They made mistakes that made problems worse.
It wasn't until late in the day that plant officials circulated enough water through the reactor that it covered the melting core that had been exposed for hours. The temperature began to decrease.
But public fear was growing fast as officials tried to regain control of the plant. By March 30, concern was spiking about the radiation that had been leaked into the atmosphere. Panic spread as scientists fretted over a hydrogen bubble that built up inside the reactor, which officials initially were worried could burn or explode.
Communications broke down. Politicians, health officials, federal bureaucrats, plant officials and executives with Babcock and Wilcox, which designed the plant, initially did not have their stories straight, which fed public anxiety.
Solid information was scarce. Increasingly hostile journalists couldn't get straight answers.
In the early hours, it was hard for officials outside the plant to get a direct phone line to the control room. Even President Jimmy Carter couldn't get through and ordered that direct lines be established.
"There was just the most bizarre flow and lack of information," Susan Stranahan, who was part of a Philadelphia Inquirer team that won a Pulitzer Prize for its Three Mile Island coverage, said at a 20-year anniversary event.

'The China Syndrome'

Public fear was further stoked by a bizarre coincidence. The movie "The China Syndrome," the fictional story of a nuclear plant accident cover-up starring Jane Fonda and Jack Lemmon, had been released just 12 days before the Three Mile Island incident. The title is a reference to the suggestion that if a nuclear plant core ever melted down it would burn a hole through the Earth all the way to China. In the movie, a scientist says that a meltdown would make "an area the size of Pennsylvania" permanently uninhabitable. In combination with the real-life drama, the film became a blockbuster.
This crisis was an early test for Pennsylvania's Republican Gov. Richard Thornburgh, who had been on the job just 68 days, he has recalled in media interviews.
"The minute I heard that there had been an accident at a nuclear facility, I knew we were in another dimension," Thornburgh told PBS for a 1999 special on Three Mile Island.
The governor quickly grew frustrated with conflicting information from officials at the plant, its owner Metropolitan Edison, and the Nuclear Regulatory Commission. The following day, Thornburgh ordered the evacuation of pregnant women and preschool-age children within a five-mile radius. About 140,000 fled.
Carter watched developments closely. The president was a nuclear engineer and understood the potential danger. On April 1, Carter and his wife Rosalynn went to the plant to help restore calm. The visit was brief but eased public fear and marked the end of the immediate crisis.

Health, Environmental Effects

Unit Two never operated again. It had cost about $700 million to construct but was open just three months. Cleanup, which continued until 1993, cost about $1 billion, the New York Times reported. The reactor's two cooling towers stand quiet to this day, in contrast to the two steam-belching Unit One towers.
Operations of the Unit One reactor were halted after the meltdown but restarted in 1985. The NRC is considering relicensing it through 2034.
It is generally agreed that the radiation released by Unit Two caused no lasting harm.
According to the NRC, among the agencies that did detailed studies of the radiological effects of the meltdown were the NRC, the Environmental Protection Agency, the Department Health and Human Services, the Department of Energy, and the state of Pennsylvania. Studies suggest that the average radiation dose to about 2 million people in the area was only about 1 millirem -- a safe dose, according to the NRC. A chest X-ray delivers about 6 millirem.
Among the recent follow-up studies was a University of Pittsburgh study of 32,100 people who lived within five miles of the plant. It found no significant difference in the rate of cancer deaths compared to the general population, the New York Times reported.
The NRC also says that investigators believe the environment was not damaged. The agency says that thousands of samples of air, water, milk, vegetation, soil and food were collected in the months following the meltdown and only "very low" levels of radionuclides were attributed to the plant.

Three Mile Island's Legacy

Nuclear power in its early days was hailed as a brilliant, futuristic answer to the nation's energy woes. The plants would produce power that was "too cheap to meter" with no greenhouse gases, industry advocates claimed.
But Three Mile Island left a legacy of public skepticism and fear that lingers a generation later. Industry advocates say that anxiety had largely faded -- at least until the disaster in Japan -- but the crisis at Three Mile Island dramatically altered the way Americans think about nuclear energy.
Three Mile Island effectively halted the advance of nuclear power in the energy-hungry U.S. In the wake of the crisis, plans that were under way for 74 new plants were canceled, according to the Union of Concerned Scientists. Since 1979, a number of plants have been decommissioned and no new plants were ordered for nearly a generation.
Today, 104 aging U.S. reactors produce about 20 percent of the nation's energy. In recent years, amid a race to develop "clean" energy and reduce oil dependence, nuclear power has enjoyed a renaissance, with powerful lawmakers singing its praises. In the last two years, nuclear utilities have filed license applications with the NRC to construct up to 26 new plants, although it would take years for the new reactors to be approved and constructed.
Proponents note that, unlike coal plants, nuclear power produces no greenhouse gases. They cite an excellent safety record since 1979. New plants also generate jobs, advocates say.
But the industry still faces obstacles, including heightened fears about safety renewed by the disaster in Japan.
The industry also is mired in a long-standing toxic debate over waste storage. Because it's extremely expensive to build nuclear plants, economic forces also remain a hurdle to industry expansion.
So does the ghost of Unit Two.
"Three Mile Island was almost 30 years ago, so perhaps the industry and the NRC have forgotten about it," Dave Lochbaum, a director at the Union of Concerned Scientists, said at a 29th anniversary event last year. "But you can bet that even the people who welcome new plants in their communities will want to know if what happened at Three Mile Island could happen to them. As of right now, the industry and the NRC haven't done enough to ensure them it won't."

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