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U.S. robot in Ukraine for continuing cleanup at ruined Chernobyl reactor
Friday, April 30, 1999 By Byron Spice, Science Editor, Post-Gazette
While a computer virus named Chernobyl was making news on Monday, the 13th anniversary of the world's worst nuclear accident, work was quietly proceeding in Ukraine to begin using a U.S. robot to help shore up the makeshift sarcophagus enclosing the crippled reactor.
Engineers from Pittsburgh's RedZone Robotics were at the Chernobyl site last week to make sure the $3 million robot, called Pioneer, had arrived safely. Lead engineer Michael Catalan said the RedZone staff will return next week to begin training the Ukrainians who will operate the diminutive, but powerful machine.
Narrow enough to fit through doorways and less than 3 1/2 feet tall at the top of its camera mast,
"It's the ultimate unstructured environment," said Maynard Holliday, Pioneer project manager at Lawrence Livermore National Laboratory in California., and cries out for study by unmanned, remotely controlled instruments.
Lethal radiation can lurk around almost any corner within the bowels of the reactor. And no one is sure anymore what is where inside the reactor building, which was blasted apart in the explosion and then absorbed ton after ton of boron, sand and concrete dumped by helicopter as workers tried to halt the nuclear reaction, stifle flames and entomb the ruined reactor.
Since 1988, Alexander Ivanov and his colleagues in Ukraine's Interbranch Scientific and Technological Center have been trying to figure out what happened, assess the stability of the sarcophagus and plan how to strengthen the shelter. The Group of Seven industrialized nations have pledged $300 million to help with the task, expected to continue for decades.
Robots have played a role from the beginning, with varying success, Ivanov said yesterday at the American Nuclear Society robotics meeting, which concluded at the Westin William Penn hotel. As early as 1986, scientists sent a four-wheel device to obtain samples from a mound of glass-like lava dubbed "elephant's foot." The solidified lava was too hard for the robot, but workers chipped off a hunk with the help of a Kalishnikov machine gun.
The first successful robot was a plastic toy tank to which researchers bolted lights and a camera to get pictures under the reactor core, Ivanov said. In 1989, researchers built an aluminum ramp and a cart outfitted with cameras and radiation detectors; by sticking the ramp underneath the massive reactor lid, they were able to use the cart to figure out whether the lid was in danger of being dislodged.
Since then, Ukrainian researchers have deployed a menagerie of remotely controlled vehicles to drill out fuel samples, cut away pipes that block access, clear rubble and monitor radiation levels. One device is used to spray surfaces with glue, which binds contaminated dust.
Pioneer will be able to perform several functions, such as producing three-dimensional maps of the areas it explores. Moving on twin tracks like a tank, it has its own bulldozer blade to clear its way. It has an environmental monitoring package designed by the Westinghouse Science and Technology Center, a drill for retrieving soda can-size concrete samples and a manipulator arm.
The robot is based on another machine called Houdini, a robot that can fold itself so it can fit inside waste storage tanks at Oak Ridge National Laboratory where it retrieves nuclear wastes. Pioneer doesn't fold, Catalan said, but the 700-pound machine can be broken down into pieces that can be hand-carried up and down stairs.
Pioneer is a joint project of the Department of Energy and the National Aeronautics and Space Administration, with the involvement of three national labs, two NASA research labs, the University of Iowa and Carnegie Mellon University.
U.S. and Ukrainian officials haven't always seen eye to eye on the project, which began two years ago. The Ukrainians objected to U.S. plans to include the $3 million cost as part of its donation to the $300 million G7 fund, saying they would prefer to spend the money in other ways. "There was a big fight over that," Holliday said, "and we blinked." Pioneer is being donated in addition to other U.S. obligations, though officials hope to use it to demonstrate U.S. robotics technology to international contractors.
Cleanup opportunities in the former Soviet republics are numerous. At yesterday's American Nuclear Society meeting, Alexander Batanov of Moscow State Technical University described how his group had designed robots to clean and monitor the roof at Chernobyl.
Robots also were called in two summers ago at Arzamas-16, a Russian nuclear weapons center, when a researcher accidentally set off a nuclear chain reaction while performing a nuclear weapons test, Batanov said. The researcher died of radiation exposure. Three robots were brought in to clean up the room, including the retrieval of five containers of plutonium.
Robots subsequently were used in Chechnya, where a highway accident left ampules containing radioactive materials strewn across the frozen ground, he added.
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