Lessons Learned

Purdue grads get firsthand knowledge of a nuclear worst-case scenario

When disaster struck Chernobyl, then part of the Soviet Union, on April 26, 1986, information was slow to emerge. In fact, the world got its first hint of the crisis a day later, not from the Soviets but rather from workers at a nuclear power plant in Sweden who detected the radioactivity. Cold War secrecy impeded the dissemination of scientific data, which in turn contributed to the tragedy of Chernobyl. Not only was it a terrible and fatal accident, but Chernobyl also became the locus of international suspicion and distrust about nuclear energy's safety.

In the summer of 2008, two young Purdue nuclear engineering alumnae set out to learn first-hand about the greatest nuclear accident in history. Carolyne Joseph (BSNE '07) and Felisa Limón (BSNE '07) journeyed to the rural spot in Ukraine to see for themselves what happened there and try to gain some perspective. They hoped to become well versed in the often-discussed disaster so that they could more convincingly debate the benefits of nuclear energy as a safe, green power alternative.

If the facts about Chernobyl remain hazy in the minds of the public, they are also less than crystalline in nuclear engineering classrooms. "In school we talked about it, but not in any great detail," says Limón. "Satisfying the curiosity we had ourselves, we realized, would benefit a lot of people." So they brought cameras and video recording equipment to capture their impressions and return with a clearer understanding of Chernobyl to share.

Distrust's long half-life

Before they left the United States on their fact-finding trip, the women needed a doctor's note clearing them for access to the site at Chernobyl. "I wasn't sure what to expect when we arrived," says Joseph, who notes that they felt more comfortable bringing their own dosimetry devices with them to tour the ruins. That token of distrust—packing their own radiation monitors for safety—is an artifact of the way information eked out from Chernobyl to the world.

Limón compares her anticipation of the Chernobyl experience with an earlier visit to Auschwitz. "I did not know how I would react, emotionally and professionally," she admits. "I was nervous I would go there and be shaken." Limón worried that the devastation at Chernobyl would cause her to second-guess her commitment to nuclear energy. She also thought she and Joseph might spend their visit combating secrecy and spin and closed doors on the past. But that is not what they experienced. "The people in Ukraine were very willing to talk. They want to help clarify the Chernobyl accident to the world," says Joseph. Limón found at Chernobyl "a sense of calm, a sense of release, because no one there denies that it happened. I felt a sense of loss, but it is, overall, a happy place. They are recovering."

Coping with catastrophe

Following the accident, a so-called Shelter Object was placed over the wrecked reactor to contain the radioactive emissions. Inside the Shelter Object, known to many as the Sarcophagus, the current dose rate is in excess of 40,000 rem/hr. Employees work in five-minute shifts once per day to minimize their exposure. Scientists at Chernobyl tell Joseph and Limón that it will be hundreds of years before Chernobyl is no longer a threat to its surroundings.

A five-step Shelter Implementation Plan was designed to minimize the environmental threat of Chernobyl long-term. The first three phases were completed in 2008, including a stabilization of the Shelter Object's west wall and the installation of a dust suppression system to contain radioactive dust particles. Phase Four is the construction and installation of the New Safe Confinement, the

largest moveable man-made object in the world. The massive semicircular dome of steel will be constructed first and then slid into place over the old Shelter Object by 2012. This will be the most critical piece for the shelter conversion into an environmentally safe system, and it will enable Phase 5: the deconstruction of Reactor 4 and burial of remaining radioactive materials, slated to be completed by 2063.

Through the years about 1,500 original residents of the rural village of Chernobyl have returned to their homes, which are marked with signs so that government patrols know residents are there. Radiation doses are safe at less than 200 mrem annually. But the nearby town of  Pripyat stands empty. Dangerous levels of radiation are concentrated in the concrete of the high-rise structures that housed workers and their families. "It's an abandoned ghost town, very eerie," says Limón. She and Joseph toured a community center in Pripyat called, ironically, the Palace of Culture, its high ceilings open to the sky now, its colorful murals crumbling, empty chairs strewn about the space.

 "But Chernobyl is very beautiful as well," Limón says. The environment, which had been so terribly damaged by the disaster, is making an astounding comeback. Where trees were once said to have glowed red from radiation, nature itself is recovering. Flora and fauna, some species of which were not in Chernobyl before the accident, are establishing themselves today. "Lack of human presence has allowed nature to flourish," Limón explains.

Chernobyl's Legacy

Joseph and Limón are eager to share their first-hand experience of Chernobyl. They are making a series of video presentations, tailored for different audiences, to help engineers and members of the public learn from the disaster. To the young engineers, those born after Chernobyl, Joseph wants the movie to say, "Respect what you do." She points to the "insane number of redundant safety systems" that are a part of their daily work and urges the up-and-coming generation of nuclear engineers to appreciate the importance of these seemingly excessive measures. "Even the smallest mistake can ruin the industry," she says.

Limón concurs. "We have a procedure for everything," she says, "and there's a reason for that: Chernobyl." The up-close footage the two filmed on their trip should help underscore the point.

And to the public, the pair hopes to be able to explain that a Chernobyl could not happen in this country. They want people to know that no reactor of the same design (the RBMK-1000) was ever built in the U.S. Limón points out that "there are risks involved with any industrial site, and in the nuclear industry that risk is technologically and physically designed for." She also notes that it is harder to start up a nuclear reactor than it is to shut it down. Redundant safety measures, in place largely because of the Chernobyl accident, would shut a reactor down in the event of any mishap.

Nuclear's Promise

Green and safe. These are two adjectives Joseph and Limón would like people to come to associate with nuclear power. "It's clean energy," Limón stresses. "Nuclear is a zero-emissions energy. It's up there with wind, solar, and hydro."

Contrasting nuclear energy production with the coal industry, Joseph wants people to know that burning coal releases naturally radioactive particles into the atmosphere. "More radiation is emitted in a day with coal than in a lifetime of nuclear-energy production," she says. And while clean coal is a promising technology, it isn't here yet.

What to do with spent nuclear fuel remains one of the greatest challenges to the nuclear-energy industry. Other countries reprocess their fuel, but that solution is currently not permitted in the U.S. The uranium and plutonium that result from reprocessing have long been confused with concerns about nuclear-weapons proliferation, a fact that hamstrings the nuclear industry. "It's an uphill battle because people have a hard time disconnecting nuclear weapons from nuclear power," says Limón. "But it's a worthwhile battle." The alternative, burying nuclear waste in a deep repository (as proposed in the beleaguered Yucca Mountain plan), is also hotly contested.

"I think the more people hear about how safe, reliable, clean, and affordable nuclear energy is, the more people will support it," says Limón. "And it's a technology that is here now." The nation currently has 104 nuclear reactors in operation, providing 20 percent of the nation's electricity. With government support, Joseph predicts that up to 10 new plants could be running or under construction within the next two decades. "Nuclear could be a limitless source of energy," she says.

-Gina Vozenilek