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Concern rises over attacks on reactors, fuel
©New York Times, WASHINGTON -- As they survey the industrial landscape for objects that terrorists could turn into weapons, members of Congress, governors and others are showing growing anxiety about the vulnerability of nuclear reactors, and especially their spent fuel. The Coast Guard and the National Guard are already patrolling many plants, and the Nuclear Regulatory Commission says improvements have been made since Sept. 11 to make reactors less susceptible to sabotage. The industry stresses that many design features intended to protect plants against accident result in "robust" structures that are also resistant to military attack. But studies that were available until recently on the Internet are being cited by a variety of others as reason to worry. One, done 20 years ago for the Nuclear Regulatory Commission, raises the possibility of an airplane crashing into a containment dome or some less-hardened part of a reactor and causing a meltdown. Another, a draft study dated September 2000, suggests that breaching a cask used to store spent fuel would create a lethal radiation dose in an area many times larger than that caused by a 10-kiloton nuclear weapon. Other experts note that the spent fuel pools can contain 20 to 30 times as much radioactive material as the reactor core does. And the spent fuel pools are in buildings that are not nearly as strong as those that house the reactors. "I'm not so worried about the core; I'm worried about the spent fuel pool," said Gov. Howard Dean of Vermont, who has asked for the establishment of a permanent 5-mile no-flight zone around the Vermont Yankee nuclear plant in the southeastern corner of his state. "There's basically no protection there," he said. Experts disagree about the extent of the vulnerability, and the Nuclear Regulatory Commission and the industry say there is no cause for alarm. But the House Energy and Commerce Committee voted on Thursday to require the commission to review the potential for attacks on nuclear plants, specifically to identify a new "design basis threat," or threat around which the plant's defenses are geared. The commission had opposed the amendment. The provision's author, Rep. Edward Markey, D-Mass., is a longtime opponent of the industry. Still, he won the near-unanimous agreement of his colleagues. His amendment would also guarantee the continued existence of the office within the NRC that evaluates physical protection at reactors. Before Sept. 11, the agency had a plan to turn that function over to an industry group, which it said could run tests more frequently. The details of the design basis threat against which the plants are tested are classified, but the threat is known to be a commando-type attack. The Nuclear Regulatory Commission's chairman, Richard Meserve, said various improvements had been made since Sept. 11, but he added that reactors were smaller than either the World Trade Center towers or the Pentagon and, thus, more difficult to crash into. "It would not be a trivial thing to have a kamikaze attack," Meserve said. "It's a lot harder to hit than the World Trade Center." While the most obvious area of concern at a nuclear plant is the reactor, which operates under high temperatures and pressures and could vent radioactive steam in an accident, the bulk of the radioactive material at most plants is in the spent fuel pool. The radioisotopes, like cesium and strontium, are created in the reactor by splitting uranium. Since the fuel is moved from the reactor after about three years, it begins to accumulate in the spent fuel pool. It sits under about 25 feet of water, which helps protect against radiation and also carries off the heat that continues to emanate from the fuel. The industry estimates that even if all cooling stopped, the water would not begin boiling for 20 to 40 hours, and that, even if it boiled, all that would be needed to end the problem is to add more water through something as simple as a fire hose.
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From the Times wire desk
From the AP |
