A year on from the Fukishima nuclear meltdown, and the strong warning against the dangers of nuclear fission energy it offers, the United States is moving forward with nuclear power, and the United Kingdom’s coalition government intends to do the same.
In the US, for the first time since 1978, the National Regulatory Commission has approved two new plants. The $14 billion facilities will be built just outside Augusta and operated by the “Southern Company” based in Atlanta, Georgia. They’re scheduled to be operating by 2016 and 2017, and be producing 10 percent of Georgia’s power.
Marilyn Brown, professor in Georgia Tech’s School of Public Policy, said:
It’s smart to continue generating nuclear power in the United States. It is a reliable, cost competitive option that doesn’t contribute to air pollution or contribute to greenhouse gas emissions.
Brown helps shape the nation’s energy policies as a board member of the Tennessee Valley Authority (TVA) and chair of the company’s Nuclear Oversight Committee. She added that nuclear power plants are expensive to build, compared to natural gas facilities…
But they are clearly worth the investment. A nuclear plant produces no carbon dioxide emissions and four times the power of a typical natural gas facility. Fourteen billion is a big number, but the plants should stay online for 50 to 70 years.
Despite the benefits, critics will always point to the risk of a nuclear catastrophe. These are the nation’s first approved nuclear facilities since Pennsylvania’s Three Mile Island accident in 1979. Experts contend that modern plant designs are much safer than those built previously. Glenn Sjoden, Georgia Tech professor of nuclear and radiological engineering, said:
The new plant designs are passively safe, so there are far fewer issues to worry about, like those that occurred with the older plants at Fukushima with the loss of offsite power. With the new plants, you have a convection cooling loop that uses gravity and runs by itself for days in the event of lost power. There would be no active pumping required… The more modern designs and precautions taken make nuclear the best option to satisfy our energy needs.
Since last year’s Japanese incident, the Nuclear Regulatory Commission has been reviewing existing US plants to ensure that they can withstand earthquakes, floods and other natural disasters and making retrofit upgrades when necessary.
Critics point to nuclear waste as another challenge with nuclear power. Each of the nation’s 104 plants store the radioactive waste onsite in steel casks protected by concrete and other safety systems. These are safe too, Brown said, because of careful construction and maintenance.
Nuclear waste would be a nonissue if the US reprocessed its spent fuel like other nations such as France, Sjoden said.
Like most nations, they recycle their used fuel, since 95 percent of the fuel can be recycled back into the reactor and used again, making nuclear power the most green energy source out there. Burying the waste, as we do in the United States, is completely wasteful.
The United States generates almost 20 percent of its energy from nuclear plants, the same amount as natural gas. Coal supplies 50 percent. The remainder is generated from hydropower and other natural sources. Brown says:
We must develop more renewables sources, such as wind, solar and biopower. Industry leaders, business and the general public must also become more energy efficient. That is the key to our future.
Unknowns
Yet, contrary to all these sweet siren voices, in a review article in the journal Science, the University of Michigan’s Rodney Ewing, a member of the US Nuclear Waste Technical Review Board, and his two colleagues note that a year after the March 11, 2011, magnitude 9.0 earthquake, and subsequent tsunami, at Japan’s Fukushima Daiichi nuclear power plant, scientists and engineers still do not know how nuclear fuels behave under extreme conditions. They are calling for a national research program to study how nuclear fuels behave under the extreme conditions present during core melt events like those that occurred at Fukushima.
Three of the plant’s six boiling water reactors suffered partial core melt events that involved tremendously high temperatures and powerful radiation fields, as well as interaction between seawater and nuclear fuel. Many tons of seawater were used to cool the overheated reactors and nearby spent fuel storage ponds, and direct discharge of contaminated seawater to the ocean and groundwater occurred for a month. The paper reviews the current understanding of interactions between nuclear fuel and the environment during core melt accidents. Ewing said:
What I realized while watching all of this was how little we actually knew about what happens if you take hot seawater and pour it on nuclear fuel.
Ewing is also a professor in Environmental Sciences, Nuclear Engineering. He is, in short, an expert on nuclear radiation and waste.
No one, as far as I know, had asked the question, “Well, what happens when you do this? Are we doing something really good or really bad?”. That kind of information really wasn’t available, and that expertise, as far as I could see, wasn’t there to be called upon.
He thought that, despite all the uncertainties and unknowns about the short and long term effects, using seawater to cool the Fukushima reactors was probably the right call.
You have a crisis, you have to cool the cores, and you can’t afford to wait around. Using the seawater sounds like the right thing to do.
The use of seawater at Fukushima underscores the need for fundamental knowledge about nuclear fuel that can be applied over a range of unanticipated situations. The research should include studies of the various radioactive materials released from damaged fuel during a core melt incident, as well as a thorough examination of how nuclear fuel interacts with fresh water and seawater. Such studies would help nuclear plant operators respond to unforeseen events, taking appropriate and timely action to minimize impacts on the environment and human health. Ewing pointed out:
An accident will be something that puts you in a situation that you didn’t anticipate, so the research focus should be on the situations you don’t expect to deal with. Right now, that kind of knowledge is fragmentary, at best.
These studies are both difficult and expensive, but are essential to reduce the risk associated with an increasing reliance on nuclear energy.
Fukushima, 11 March 2011
Most of the fuel in the reactors was uranium dioxide. When the tsunami inundated the site about 40 minutes after the earthquake, electrical power was lost, followed by the loss of onsite backup power, resulting in a station blackout and the loss of reactor coolant. A partial core melt event ensued in units 1, 2 and 3. The Japanese operator, the Tokyo Electric Power Company or TEPCO, guessed there was a nearly immediate loss of core cooling in unit 1, and almost all of its fuel assemblies melted and accumulated in the bottom of the pressure vessel. Partial melting of the cores in units 2 and 3, damaging a third of the fuel assemblies in each, occurred over the following days.
Reaction of the zirconium alloy fuel cladding with water at high temperatures generated hydrogen gas that accumulated and exploded in four of the reactor units. The release of radioactivity, other than gaseous and volatile fission products, was dominated by the many tons of seawater used to cool the cores and storage pools.
A month on, Tokyo finally upgraded its assessment of the severity of the nuclear emergency to a maximum seven on an international scale—equal with Chernobyl. It was not until May 5 that workers were able to get inside the reactor building for the first time, to see the size of the task ahead of them.
During the nuclear crisis that followed, hundreds of people were exposed to increased levels of radiation. 80,000 or more people were evacuated from the area nearest the Fukushima plant. A year later, all but two of Japan’s 54 nuclear reactors remain shut following the precautionary closure of nuclear plants, in a country where nuclear power once supplied nearly 30 percent of the electricity, and all those people remain displaced. Although the Japanese government has declared the plant stable, and it is awarding an initial $13 billion in contracts to begin decontamination and rehabilitation of the more than 8,000 square mile region most exposed to radioactive fallout, the cleanup will be expensive and is expected to take decades, perhaps 40 years.
Under Control? Dissenting Voices!
TEPCO and the Japanese government say things are under control at Fukushima—the tsunami crippled reactors are all in a “state of cold shutdown”—and they are keen to give the impression that there is just cleaning up to do. But that is not how those who spend their days inside the plant see it. One worker in his 50s, a subcontractor who has been working on the plant’s cooling system since September, said:
I can clearly say it’s not safe at all. There are many spots where radiation levels are extremely high,
The man said subcontractors like him were treated like animals. He did not want to be identified for fear of losing the 8,000 yen ($100) daily paycheck he receives.
There have been deaths on site—a 60 year old subcontractor’s fatal heart attack in May was put down to overwork, according to a labour standards inspector—although TEPCO says none related to radiation exposure. In the height of summer with the mercury rising to 38 degrees Celsius (100 Fahrenheit), workers had to go for up to three hours at a time without water because they were unable to take off their masks.
Chie Hosoda, a spokeswoman for the utility, admits conditions at the plant were unacceptable in the past, with the radiation exposure of some workers left unmeasured because of a shortage of dosimeters:
But working conditions have improved now and we are strictly checking the radiation exposure of all workers
TEPCO says at least 167 workers are no longer able to work in nuclear plants because their lifetime radiation exposure has topped 100 millisieverts—the upper limit for workers. Engineers, nuclear experts and ordinary electricians are among the 3,600 people working at the plant every day and TEPCO says it has no problems securing a work force despite the obvious hazards. But one worker told the Tokyo Shimbun:
Those who used to work at the Fukushima nuclear plant for a long time do not go to Daiichi because it’s dangerous. Payment is not good and many of them do not want to lose their jobs by risking exposure to high levels of radiation.
Katsuyasu Iida, secretary general of Tokyo Occupational Safety and Health Centre, a support group for low paid workers, warned the utility may face a labour shortage “if it fails to improve working conditions”. Many with experience in the industry shy away from the plant.
Experts warn that few permanent safety measures are in place at the plant, where the initial rush to contain the accident saw a series of improvised solutions. They say that in another natural disaster—a big earthquake or another large tsunami—the plant could prove very vulnerable. Kazuhiko Kudo, a nuclear reactor expert and professor at Kyushu University said:
The cooling system is not a proper one for normal nuclear reactors and is still a stop-gap measure.
News of setbacks regularly emerge. In early February, TEPCO said radioactive water had spilled out of one of the reactors after a valve in the cooling system jammed, frozen by subzero winter temperatures.
One of the biggest challenges, as Professor Ewing said, is that scientists do not know exactly what they are up against and can only speculate what the inside of the reactors look like—how much of the fuel has melted and how far through containment vessels it has eaten. Kudo said that containment was still a priority and the risk of radiation was still high:
Stabilisation of the plant is a prerequisite for an end to the accident.
Freelance journalist Tomohiko Suzuki, who has written a book based on his experience working undercover at the plant last summer, said it was clearly still “in a state of crisis”. He said:
[TEPCO] was pushing for sloppy construction as it has been in a hurry to achieve cold shutdown as quickly as possible. TEPCO has to maintain this cold shutdown status for years and years to come, but can they make it happen without exposing plant workers to radiation? That’s the question.
The Reaction of the Authorities
The Rebuild Japan Initiative Foundation (RJIF) established an independent investigation panel to review how the government, TEPCO, and other key organizations responded during the disaster. The foundation’s chairman, Yoichi Funabashi, and staff director of the investigation panel, Kay Kitazawa, explain the reasons behind the lack of disaster preparation. Their findings are based on interviews with nearly 300 people involved in the accident, including then Prime Minister, Naoto Kan.
Kan secretly instructed Shunsuke Kondo, chairman of the Japan Atomic Energy Commission (AEC), to draw up a “worst case scenario” for the nuclear accident as the crisis deepened—that is, six increasingly drastic scenarios that would play out as various systems at the nuclear plant failed. The RJIF panel obtained a copy of this plan and published it in the Bulletin. The most extreme scenario would have involved evacuation of all residents living within 170 km or more of the Fukushima plant, and, depending on the wind direction, could have meant evacuating the 30 million residents in the Tokyo metropolitan area.
According to the investigation, the tsunami could and should have been anticipated. Earlier research on the Jogan tsunami of 869 AD showed that high water levels should not have been considered unprecedented along the Japanese coastline where Fukushima is located. TEPCO’s own nuclear energy division understood the risk, but the company dismissed these probabilities as “academic”. Regulatory authorities also encouraged the company to incorporate new findings into its safety plans, but did not make these measures mandatory.
Many human errors were made at Fukushima, illustrating the dangers of building multiple nuclear reactor units close together. Masao Yoshida, the director of the Fukushima Daiichi Nuclear Power Station at the time of the accident, had to cope simultaneously with core meltdowns at three reactors, and exposed fuel pools at four units. The errors were not the fault of one individual, but were systemic. When onsite workers sought answers in the official guide, the Severe Accident Manual, they were not there. And those who misjudged the condition of the emergency cooling system had never actually put the system into service. They had not been trained for such a crisis.
The reports says TEPCO bears the primary responsibility for incompetent handling of the disaster’s aftermath. The organisation failed to make rapid decisions, losing government trust in the process. It highlights government regulators, including the Nuclear and Industrial Safety Agency (NISA), and the Nuclear Safety Commission (NSC) for their poor response. The Japanese government’s System for Prediction of Environmental Emergency Dose Information (SPEEDI) was designed to help governments decide when to evacuate in the event of a radioactive leak. The system was not used, negating the time and money invested in developing the system in the first place. The Japanese government is now considering the creation of a new nuclear safety agency to replace NISA and NSC and be constructed as an external organ of the Environment Ministry.
A public myth of “absolute safety”, nurtured by nuclear power proponents over decades, and being echoed afresh by Marilyn Brown, et al, contributed to the lack of adequate preparation. The public was also ill informed about the meaning of reported radiation levels. The authors conclude:
It’s clear from our investigation of the Fukushima Daiichi accident that even in the technologically advanced country of Japan, the government and the plant operator, Tokyo Electric Power Company, were astonishingly unprepared, at almost all levels, for the complex nuclear disaster that started with an earthquake and a tsunami. And this grave oversight will affect the Japanese people for decades.
Worries of Concerned Scientists
In a study by the Union of Concerned Scientists (UCS) entitled, “The NRC and Nuclear Power Plant Safety in 2011: Living on Borrowed Time”, 15 cases of safety equipment problems and security shortcomings at 13 nuclear plants were reported during the last year, a “high” number, although no employees or members of the public were harmed in the incidents. Even so, the lapses were serious enough to warrant special inspections by the US Nuclear Regulatory Commission (NRC), which has oversight of the industry and which had itself a mixed record in responding to the problems.
In some instances the NRC did an outstanding job of addressing safety problems before they could lead to a potentially dangerous situation, but there were other times when the federal agency did a less than adequate job of cracking down on nuclear plant owners, who in some cases have flouted agency regulations for decades. Dave Lochbaum, a nuclear engineer with 17 years of experience working at nuclear plants, lead author of the report, and the director of UCS’s Nuclear Safety Project, said…
…the agency too often does not live up to its potential, and we are still finding significant problems at nuclear plants that could too easily trigger a serious accident.
Lax NRC oversight has allowed some problems to fester for decades, and found there are 27 reactors with inadequate protection against earthquakes, and 47 nuclear reactors—nearly half of the 104 nuclear plants operating in the United States—still do not comply with fire regulations established by the NRC in 1980 and amended in 2004. Lochbaum said:
That US plant owners could have avoided nearly all the near misses in 2011 if they had addressed known problems in a timely manner suggests that they and the NRC have not learned the lessons of these accidents. Someday their luck may run out.
The vulnerability of nuclear reactors to earthquakes was underscored after problems following a magnitude 5.8 quake that rattled the US East Coast last August, damaging two reactors at the North Anna plant in Virginia, some 12 miles (20 kilometers) from the epicenter of the tremor. Owners of atomic plants too often either close an eye to problems or fail to address them adequately.
Do we want to put our lives, and more importantly, the lives of our children in the hands of smug self-congratulatory back-slappers whose perpetual optimism in the face of warning after warning can be nothing other than insanity? This planet gets enough energy everyday from the sun, and some from the moon, and we can tap it naturally whether directly, or when it has changed into wind power water power, wave power, tidal power, and so on. It is sustainable energy. And we have the technology to overcome problems of the variability of supply.
Fossil fuels are poisoning the air now, and causing global warming. Nuclear energy can never be totally safe, and the waste from it will be radioactive when no one knows where it has been buried. If we do not destroy the human race soon, we will set up a time bomb for its destruction. No one motivated by greed and self aggrandisement will care a toss, but the rest of us do, or should, and we should not be taken in.
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