Reprocessing facility accidents: On March 11, 1997, forty workers were exposed to radiation at a Tokaimura reprocessing facility in Japan. In the United States, a commercial and military reprocessing facility that operated from 1966 to 1972 at West Valley in Buffalo, New York, experienced so many incidents of fire, leaking, and worker overexposure that it only managed one year’s worth of reprocessing. The cost of cleaning the site up is between 10 and 27 billion dollars. If it is not cleaned up, it will erode into Lakes Erie and Ontario.
Inadvertent criticalities: Fermi Unit 2, which is the largest GE Mark I boiling-water reactor in the world—the same design as at Fukushima Daiichi, only nearly as large as Units 1 and 2 put together—experienced an inadvertent criticality in 1985. Michael Keegan at Don’t Waste Michigan uncovered the accident and the reactor was shut down for three years because it did not yet have a permit to operate. Luckily no one was hurt.
On June 18, 1999, during an inspection, operators were to perform an emergency control rod insertion on Shika Unit 1 in Japan’s Ishikawa Prefecture. Due to improper procedure, instead of inserting one rod into the reactor, three rods were withdrawn. For the next fifteen minutes, the reactor was in a dangerous criticality state. This event was covered up and not revealed until March 15, 2007. A second, much more serious Tokaimura nuclear accident—a fatal inadvertent criticality—occurred on September 30, 1999, as three workers were preparing a small batch of fuel for an experimental fast-breeder reactor. It resulted in two workers’ deaths, and the exposure of hundreds of other workers and local residents to radioactivity doses above so-called permissible levels.
Cover-ups: In 2000, three TEPCO executives were forced to resign after the revelation that in 1989 the company had ordered an employee to edit out video footage showing cracks in nuclear plant steam pipes. In August 2002, a widespread falsification scandal led to the temporary shutdown of all of TEPCO’s seventeen atomic reactors: company officials had falsified inspection records and attempted to hide cracks in reactor vessel shrouds in thirteen reactors. Nevertheless, TEPCO was allowed to restart the reactors. According to Aileen Mioko Smith at the Japanese organization Green Action, there was another cover-up in Japan that was brought to light by the Japanese antinuclear movement: in 1999, British Nuclear Fuels’ MOX fuel arrived in Japan with falsified quality assurance documentation, which caused a major delay in plutonium fuel loading in Japan. Unfortunately, the first MOX was loaded into Fukushima Daiichi Unit 3 just six months prior to the March 11 catastrophe. Unit 3 suffered the biggest explosion of all.
Another cover-up, in the United States, took place at Davis-Besse, Ohio, which had a massive corrosion hole in the lid of its reactor in 2002 and came within three-sixteenths of an inch of breaching the seven-inch carbon steel lid. Video footage was edited before the NRC saw it, but the commission had photographic evidence of a lava-like stream of boric acid crystals and rust coming off the lid. Despite this, no regulatory action was taken. The fingerprints of former NRC chairman Richard Meserve were all over this near-disaster. Junior inspectors at the NRC wanted to shut the plant down for inspections. Instead, Meserve and others in senior management at NRC allowed the reactor to continue operating. The office of the inspector general later reported that NRC had prioritized company profits over public safety. Meserve resigned shortly afterward yet is still called upon to present on nuclear safety matters, even in Tokyo. He has served on numerous legal and scientific communities over the years, including many established by the National Academies of Sciences (NAS) and Engineering (NAE). Tipped off about Meserve’s membership on two for-profit nuclear utility corporate boards—at Pacific Gas & Electric, which owns Diablo Canyon nuclear power plant in California, and Luminant, which owns Comanche Peak in Texas—Beyond Nuclear successfully demanded Meserve’s recusal from the board’s analysis of cancer risks in populations near nuclear facilities.
Steam explosions: At Mihama 3 in Fukui Prefecture, four workers were killed by a steam explosion on the 2004 anniversary of the dropping of the bomb on Nagasaki. The subsequent investigation revealed a significant lack of systematic inspections at Japanese nuclear power plants.
Surry Nuclear Power Plant in Virginia has experienced two separate accidents, in 1972 and 1986. The former killed two workers, the latter four—the single largest immediate loss of human life at a U.S. nuclear power plant. Surry is also infamous for experimenting with various types of dry cask storage. There have been leaks of inert heat transfer gas out of one seal and possibly out of a second. Complete seal failure leakage would allow oxygen to enter the cask and the waste to overheat, leading to corrosion or deterioration of the irradiated nuclear fuel inside.
Nonfatal radioactive steam releases: In 2006, Fukushima Daiichi itself experienced a radioactive steam release. An especially controversial incident was in January 2012, when radioactive steam was released from a failed steam-generating tube at San Onofre in Southern California. As a result, the two units in San Onofre were shut down. Extensive, dangerous tube degradation was discovered in nearly new replacement steam generators, which had cost $671 million. This was due to faulty design and fabrication performed by Mitsubishi Heavy Industries of Japan. In June 2013, Southern California Edison announced the permanent shutdown of both reactors. The total cost of the fiasco is now in the billions of dollars, with legal disputes as to who will pay.
Earthquakes: On July 16, 2007, a severe earthquake measuring 6.8 on the Richter scale hit the region where TEPCO’s Kashiwazaki-Kariwa nuclear power plant is located. Radioactive water spilled into the Sea of Japan, a transformer caught on fire, and radioactive waste containers were jostled and overturned. The plant, with seven reactors, is the single largest in the world. Although a small number of Kashiwazaki-Kariwa’s reactors had returned to service by March 11, 2011, the entire plant was shut down shortly thereafter, and it remains shut down to the present day. This is a testament to popular resistance on the local level and the hard work of a burgeoning antinuclear movement, including unprecedentedly frequent and large-scale protests, including some numbering hundreds of thousands. Prime Minister Abe remains determined to restart reactors, despite the risks.
Entergy’s Indian Point nuclear plant, in Buchanan, New York, is located immediately adjacent to fault lines that were discovered long after it was constructed. Seismologists at Columbia University confirmed their existence in 2008. The NRC was then forced to admit that this is probably the most vulnerable nuclear power plant in the United States to earthquakes, which it was not constructed to withstand. The Diablo Canyon atomic reactors in California are also vulnerable to earthquakes but are more sturdily built because engineers knew of the proximity of the San Andreas Fault. But in recent years, previously unknown fault lines immediately adjacent to Diablo Canyon have also been discovered.
Reactor pressure vessel embrittlement: Another risk, faced specifically by pressurized water reactors, is reactor pressure vessel embrittlement due to the neutron bombardment of the approximately eight-inch thickness of a reactor pressure vessel over years and decades. The impurities in the metal can create cracks that can line up, decreasing the metal’s ductility. If the emergency core cooling systems are ever activated, as the final line of defense to prevent a meltdown, the thermal shock of the temperature decrease, combined with the very high pressure, can fracture these vessels, like a hot glass under cold water. If that happens, there will be an irreparable loss of core coolant. There would be no contingency in place to prevent a core meltdown. Genkai 1 in Saga Prefecture on Kyushu, and Entergy’s Palisades in Michigan, have the worst embrittled RPVs in Japan and the United States, respectively.