Is the Era of Nuclear Power Coming to an End in the US?
Continued from previous page
"GE wants us not to mention the problem publicly," Hanauer wrote. "In any event, this is probably trouble for the Vermont Yankee and Pilgrim hearings; it will have to be faced and a real solution found." Hendrie replied that other designs were safer, but that acceptance of the Mark I design was "firmly embedded in the conventional wisdom," and that "Reversal of this hallowed policy, particularly at this time, could well be the end of nuclear power. It would throw into question the continued operation of licensed plants."
Another problem with the Mark I design, Gundersen says, is the core shroud, the doughnut-shaped concrete rings that surround the reactor to absorb neutrons and keep the reaction from getting out of hand. By the late 1980s, he says, these had become so brittle they were "literally beginning to shatter" in some reactors.
The Japanese shut down reactors to replace these core shrouds, interjects Maggie Gundersen, her husband's partner in the Fairewinds Associates energy consultants in Burlington, Vt. The Americans just put bolts in to reinforce them, says Arnie Gundersen.
Two other safety issues at Vermont Yankee, says Maggie Gundersen, are the plant's "uprating" -- after Entergy bought the plant in 2002, it began running the plant at 650 megawatts, 20 percent over its previous capacity -- and waste storage. As the U.S. has no permanent facility to store radioactive waste, Vermont Yankee now has 33 years worth of spent fuel on the site. These old fuel pools contain 10 times the amount of radioactive cesium-137 that was released at Chernobyl and three times as much as there was at Fukushima, she says.
Entergy, a Louisiana-based power company that operates 12 nuclear power plants at ten sites in seven states (including Pilgrim and Indian Point), declined to comment. The company Web site for Vermont Yankee says it produces more than one-third of the state's electricity, and says the uprate was important "because more electricity will be needed in the coming years." When a federal waste-storage facility opens, it says, "Vermont Yankee will be among the first plants in the country eligible to ship spent fuel there." (A 1982 law says one was supposed to be opened by 1998, but the federal government's plans to do that at Yucca Mountain, Nevada have been stalled by opposition from state residents and the engineering difficulties of designing a structure that would last for 10,000 years.)
The Nuclear Regulatory Commission insists that the Mark I plants are safe. At Fukushima, says Northeastern-region spokesperson Neil Sheehan, "a severe earthquake knocked out the offsite power, and then a tsunami knocked out the backup power" -- a combination highly unlikely to happen in the United States, especially at inland plants.
There have not been any issues with the core shrouds since the 1990s, he says, since they were repaired at the Oyster Creek plant in New Jersey and Nine Mile Point in upstate New York.
Since Fukushima, Sheehan says, the NRC has begun reviewing seismic conditions around nuclear plants and their operators' plans for coping with flooding, supplying backup power, and emergency preparedness. These reviews are "still in the early stages," he says, but "in the meantime, we think the plants can continue to operate safely."
The NRC believes the plants can run safely for at least 60 years, he says. Its "aging management" program includes inspecting the condition of the reactor-coolant pump; assessing the frequency of maintenance, testing, and replacement of parts; and testing the structural integrity of pipe supports. The 40-year length of the initial operating licenses, he says, had more to do with economic and antitrust concerns than with safety.