And then there's the human element: The accident at Three Mile Island was made worse by operators reading a lack of cooling water as too much water in the reactor. And, in 1990, Plant Vogtle in Georgia lost all externally supplied electric power—just like Fukushima Daiichi's reactors—when a truck backed into a transmission line and the backup diesel generator failed, forcing it to rely on its last power source: batteries with an eight-hour life.
The U.S. has endured a slew of "near misses" in recent years: a 0.48-centimeter thick stainless steel lining is all that stood between Davis–Besse nuclear power plant in Ohio and a meltdown in 2002. And in 2010, alone, the NRC launched 14 investigations into safety-related issues at U.S. nuclear plants. "Many of these significant events occurred because reactor owners, and often the NRC, tolerated known safety problems," wrote David Lochbaum a nuclear engineer with the Union of Concerned Scientists in a report examining the 2010 track record. According to Lochbaum, the NRC overlooks some safety problems, such as a refueling-cavity liner leaking at the Indian Point facility in New York State since 1993. "By allowing this reactor to continue operating with equipment that cannot perform its only safety function, the NRC is putting people living around Indian Point at elevated and undue risk," Lochbaum writes.
The nuclear industry certainly has a history of ignoring potential problems until they become critical. Flaws in the boiling-water reactor safety system at Fukushima Daiichi (as well as Oyster Creek and Vermont Yankee) had been known since 1972. The potential for Inconel 600 to crack under pressure was first identified in the 1950s. A new report from the NRC Inspector General notes that nuclear power plant operators have consistently failed to report equipment defects. And the U.S. National Academy of Sciences in 2006 suggested the practice of overcrowding pools for the storage of spent nuclear fuel rods—that has caused fires and explosions at Fukushima Daiichi, which stores far less used fuel than typical U.S. plants—could prove dangerous.
This problem continues to grow because there remains no place for used nuclear fuel rod storage other than such pools or massive dry casks—both located on nuclear facility grounds. Yet, since 2000 more than half of the U.S. fleet of nuclear reactors have received 20-year operating extensions, piling yet more (thermally and radioactively) hot nuclear rods into their spent-fuel cooling pools.
Regardless of those extensions, all U.S. nuclear power plants currently in operation most likely will be decommissioned by 2050. Replacing them, however, may prove more difficult than extending their useful lives. Simply swapping old for new would require starting construction on a new reactor every six months for the next 40 years. As it stands, there are four new reactors under construction in the U.S.—and applications for another 16.
And that's why the U.S. Department of Energy, the NRC and industry are currently assessing whether the first-generation plants could operate another 20 years—thereby lengthening the life span of a given reactor to 80 years. "The NRC is a full participant into the ongoing research examining whether it's technically feasible to consider 'second' renewals to extend reactor operating life," Burnell says. "The matter has yet to be decided."
Editor's Note: David Biello is the host of a forthcoming series on PBS this April, titled "Beyond the Light Switch." The series, produced by Detroit Public Television, will explore how transformation is coming to how we use and produce electricity, impacting the environment, national security and the economy.