Six years after Fukushima, robots finally find reactors’ melted uranium fuel — The New York Times

” FUKUSHIMA DAIICHI NUCLEAR POWER PLANT, Japan — Four engineers hunched before a bank of monitors, one holding what looked like a game controller. They had spent a month training for what they were about to do: pilot a small robot into the contaminated heart of the ruined Fukushima nuclear plant.

Earlier robots had failed, getting caught on debris or suffering circuit malfunctions from excess radiation. But the newer version, called the Mini-Manbo, or “little sunfish,” was made of radiation-hardened materials with a sensor to help it avoid dangerous hot spots in the plant’s flooded reactor buildings.

The size of a shoe box, the Manbo used tiny propellers to hover and glide through water in a manner similar to an aerial drone.

After three days of carefully navigating through a shattered reactor building, the Manbo finally reached the heavily damaged Unit 3 reactor. There, the robot beamed back video of a gaping hole at the bottom of the reactor and, on the floor beneath it, clumps of what looked like solidified lava: the first images ever taken of the plant’s melted uranium fuel.

The discovery in July at Unit 3, and similar successes this year in locating the fuel of the plant’s other two ruined reactors, mark what Japanese officials hope will prove to be a turning point in the worst atomic disaster since Chernobyl.

The fate of the fuel had been one of the most enduring mysteries of the catastrophe, which occurred on March 11, 2011, when an earthquake and 50-foot tsunami knocked out vital cooling systems here at the plant.

Left to overheat, three of the six reactors melted down. Their uranium fuel rods liquefied like candle wax, dripping to the bottom of the reactor vessels in a molten mass hot enough to burn through the steel walls and even penetrate the concrete floors below.

No one knew for sure exactly how far those molten fuel cores had traveled before desperate plant workers — later celebrated as the “Fukushima Fifty” — were able to cool them again by pumping water into the reactor buildings. With radiation levels so high, the fate of the fuel remained unknown.

As officials became more confident about managing the disaster, they began a search for the missing fuel. Scientists and engineers built radiation-resistant robots like the Manbo and a device like a huge X-ray machine that uses exotic space particles called muons to see the reactors’ innards.

Now that engineers say they have found the fuel, officials of the government and the utility that runs the plant hope to sway public opinion. Six and a half years after the accident spewed radiation over northern Japan, and at one point seemed to endanger Tokyo, the officials hope to persuade a skeptical world that the plant has moved out of post-disaster crisis mode and into something much less threatening: cleanup.

“Until now, we didn’t know exactly where the fuel was, or what it looked like,” said Takahiro Kimoto, a general manager in the nuclear power division of the plant’s operator, Tokyo Electric Power Co., or Tepco. “Now that we have seen it, we can make plans to retrieve it.”

Tepco is keen to portray the plant as one big industrial cleanup site. About 7,000 people work here, building new water storage tanks, moving radioactive debris to a new disposal site, and erecting enormous scaffoldings over reactor buildings torn apart by the huge hydrogen explosions that occurred during the accident.

Access to the plant is easier than it was just a year ago, when visitors still had to change into special protective clothing. These days, workers and visitors can move about all but the most dangerous areas in street clothes.

A Tepco guide explained this was because the central plant grounds had been deforested and paved over, sealing in contaminated soil.

During a recent visit, the mood within the plant was noticeably more relaxed, though movements were still tightly controlled and everyone was required to wear radiation-measuring badges. Inside a “resting building,” workers ate in a large cafeteria and bought snacks in a convenience store.

At the plant’s entrance, a sign warned: “Games like Pokemon GO are forbidden within the facility.”

“We have finished the debris cleanup and gotten the plant under control,” said the guide, Daisuke Hirose, a spokesman for Tepco’s subsidiary in charge of decommissioning the plant. “Now, we are finally preparing for decommissioning.”

In September, the prime minister’s office set a target date of 2021 — the 10th anniversary of the disaster — for the next significant stage, when workers begin extracting the melted fuel from at least one of the three destroyed reactors, though they have yet to choose which one.

The government admits that cleaning up the plant will take at least another three to four decades and tens of billions of dollars. A $100 million research center has been built nearby to help scientists and engineers develop a new generation of robots to enter the reactor buildings and scoop up the melted fuel.

At Chernobyl, the Soviets simply entombed the charred reactor in concrete after the deadly 1986 accident. But Japan has pledged to dismantle the Fukushima plant and decontaminate the surrounding countryside, which was home to about 160,000 people who were evacuated after accident.

Many of them have been allowed to return as the rural towns around the plant have been decontaminated. But without at least starting a cleanup of the plant itself, officials admit they will find it difficult to convince the public that the accident is truly over.

They also hope that beginning the cleanup will help them win the public’s consent to restart Japan’s undamaged nuclear plants, most of which remain shut down since the disaster.

Tepco and the government are treading cautiously to avoid further mishaps that could raise doubts that the plant is under control.

“They are being very methodical — too slow, some would say — in making a careful effort to avoid any missteps or nasty surprises,” said David Lochbaum, director of the nuclear safety project at the Union of Concerned Scientists, who was a co-author of a book on the disaster.

“They want to regain trust. They have learned that trust can be lost much quicker than it can be recovered.”

To show the course followed by the Manbo, Tepco’s Mr. Hirose guided me inside the building containing the undamaged Unit 5 reactor, which is structurally the same as two of the destroyed reactors.

Mr. Hirose pointed toward the spot on a narrow access ramp where two robots, including one that looked like a scorpion, got tangled in February by debris inside the ruined Unit 2.

Before engineers could free the scorpion, its monitoring screen faded to black as its electronic components were overcome by radiation, which Tepco said reached levels of 70 sieverts per hour. (A dose of one sievert is enough to cause radiation sickness in a human.)

Mr. Hirose then led me underneath the reactor, onto what is called the pedestal.

The bottom of the reactor looked like a collection of huge bolts — the access points for control rods used to speed up and slow down the nuclear reaction inside a healthy reactor. The pedestal was just a metal grating, with the building’s concrete floor visible below.

“The overheated fuel would have dropped from here, and melted through the grating around here,” Mr. Hirose said, as we squatted to avoid banging our heads on the reactor bottom. The entire area around the reactor was dark, and cluttered with pipes and machinery.

To avoid getting entangled, the Manbo took three days to travel some 20 feet to the bottom of Unit 3.

To examine the other two reactors, engineers built a “snake” robot that could thread its way through wreckage, and the imaging device using muons, which can pass through most matter. The muon device has produced crude, ghostly images of the reactors’ interiors.

Extracting the melted fuel will present its own set of technical challenges, and risks.

Engineers are developing the new radiation-resistant robots at the Naraha Remote Technology Development Center. It includes a hangar-sized building to hold full-scale mock-ups of the plant and a virtual-reality room that simulates the interiors of the reactor buildings, including locations of known debris.

“I’ve been a robotic engineer for 30 years, and we’ve never faced anything as hard as this,” said Shinji Kawatsuma, director of research and development at the center. “This is a divine mission for Japan’s robot engineers.” “

by Martin Fackler, The New York Times

source with photos, video and internal links

Advertisements

Fukushima: The Story of a Nuclear Disaster — Truthdig book review

The following is a book review by Louise Rubacky for Fukushima: The Story of a Nuclear Disaster, written by David Lochbaum, Edwin Lyman, Susan Q. Stranahan and the Union of Concerned Scientists.

” In “Fukushima: The Story of a Nuclear Disaster,” a team of scientists and a Pulitzer Prize-winning journalist recount what happens when a catastrophe strikes that no one imagines. No one with the clout to prevent it, that is. It’s a tale of entwined worlds that must cooperate intelligently in order to protect the public. The tensions and cross-purposes among them, however, lead to indecision, inaction and increased calamity. In crisis, these worlds—the nuclear energy industry, two powerful governments, and international regulatory commissions—are about as effective as a machine lubed with super glue.

Early and often comes the warning: Hubris Ahead. Words and phrases like prevailing wisdom, low risk, practically unthinkable, unlikely, government assurances, assumptions, confidence, remote possibility and a situation we had never imagined appear throughout; they indicate attitudes about potential dangers, and point to why the earthquake and tsunami had such dire effects on Fukushima Daiichi Nuclear Power Plant and Japan.

This chronicle, another in the continuing tragedy of the human gamble against nature, is mostly peopled by players who could be said to represent knowledge, fear, power and money. In standing, the first of these comes last. Corporate captains, regulators and leaders charged with public safety cover up or sidestep facts that, if acknowledged and addressed, could imperil their coffers or careers. As in the U.S., there’s a symbiotic and dangerous relationship between government and industry in Japan. The route from the public to the private sector is known here as the revolving door; there, the delicate name for that greasy highway is “amakudari,” translated as “descent from heaven.”

The coastal earthquake that kicked off a trail of destruction and mayhem on March 11, 2011, measured 9.0 on the Richter scale, but was prematurely reported by the government as 7.9, 45 times less energetically powerful. It’s the biggest temblor in Japanese history, but the fifth largest ever recorded, and the authors present other reasons that industry and government should not have feigned surprise:

“Headlines scattered over the decades built a disturbing picture. Reactor owners falsified reports. Regulators failed to scrutinize safety claims. Nuclear boosters dominated safety panels. Rules were buried for years in endless committee reviews. ‘Independent’ experts were financially beholden to the nuclear industry for jobs or research funding. …”

Plenty of warnings were sounded, like those from noted seismologist Katsuhiko Ishibashi who, since 1997, had predicted grim scenarios that a catastrophic earthquake could set in motion. Other experts cautioned that tsunami reinforcements at Fukushima Daiichi were inadequate; they were made safe only up to 20 feet because plant owner Tokyo Electric Power Company determined the danger of a wave above that height was “unrealistic.” In an island nation that generated 30 percent of its energy at nuclear plants and has over 1,000 earthquakes a year, company concerns about sending the wrong message to the public outweighed scientific evidence.

When the tsunami hit Fukushima Daiichi, system failures flowed like lava from an active volcano. For three of their six reactors, the countdown to meltdown began. The earthquake took out plant AC power, and the tsunami drowned backup generators, cables, gauges and multiple critical tools. Internal emergency communications became spotty, as would be expected if those in charge had allowed themselves to imagine that such a destructive earthquake and tsunami could happen.

Within two hours of the 50-foot water wall flooding the plant, all backups for disaster control were kaput. The Fukushima incident was, like many nuclear accidents, “beyond design-basis.” This refers to power stations designed with accident management plans that function up to a certain degree of impact intensity. That threshold was much lower than the 9.0 quake and subsequent tsunami. Despite the risk, the Nuclear Regulatory Commission has also allowed U.S. plants to rely on design-basis planning, and for licensees to develop their accident management voluntarily. (Taking plants offline for seismic evaluation and upgrades is expensive: After the 2007 earthquake near the Kashiwazaki-Kariwa nuclear power plant, all seven of its reactors underwent work. That cut production by 20 percent; owner TEPCO lost $1.44 billion and its stock fell 30 percent that year.)

Even more difficult to fathom, TEPCO set accident management procedures for station blackouts that would last just 30 minutes and affect only one reactor per site. But no nuclear accident resulting in blackout to date has affected only one reactor. Further, no worker has ever been trained at any nuclear plant for “worst case scenario” responses, because that’s a hot concept, politically speaking. Nor has failure of all backup defenses ever been considered. Consequently, unprepared workers attempted to control beyond-design chaos of a disaster eventually rated level 7, the worst on the 1-7 nuclear accident scale. Oh, and the Fukushima plant blackout lasted 10 days.

Over the next few days after the tsunami, explosions blew out parts of four containment structures, dramatically increasing the potential radiation hazard to workers and the public. Because of the blackout, no one was sure which likely cause was behind each explosion. Desperate and resourceful attempts were made to get water into the structures to cool reactors, many unsuccessful because of debris blocking outside access, inadequate pumping tools and weak jury-rigged power sources. Broken pressure gauges, radiation detectors and measuring tools, on top of scarce information inside and between containment structures, meant everyone was working in perilous best-guess mode.

The complexities were many, and the authors explain known factors contributing to the cascade of dangerous dominoes, often more than once—the timing and dangers of cooling procedures, hydrogen, spent fuel pools, fissile material behavior, venting pros and cons, and more. (Mysteries about specific stages of the accident will never be solved because life-threatening radiation levels at the power plant still prevent forensic investigation.) Incomplete or wrong information from TEPCO and government officials circulated, and multiple versions are reported here, including corrections. Exhaustion and a 13-hour time difference between Washington, D.C., and Japan further muddied communication.

Washington became involved in the disaster quickly for a few reasons: The Nuclear Regulatory Commission, from which the president and Congress get information and advice on science, industry and policy matters, is located just outside D.C. Also, about 160,000 American citizens lived in Japan in 2011. But perhaps most worrying were the 35 reactors and 23 containment structures in use at U.S nuclear power plants that were the same type as the ones failing at Fukushima Daiichi. The Mark 1 reactors and containment structures were all designed and manufactured by General Electric. A rather large question loomed: Could this happen in the U.S.?

The interactions and impacts of the international regulatory agencies are as complicated as the technical parts of the story. Few in this arena come off as even halfway responsible; many appear cowed by industry expectations. Their appeasing, obfuscating ways preceded the accident and have persisted since. (Arguments continue about how many people’s health was really destroyed from the radiation.) Still, it comes as a big WOW when the contents of an NRC conference report, and its date, are revealed in Chapter 10.

“Now, as the [international] conference was winding down, a few dozen people had gathered to hear a panel discuss the latest results of an NRC research project entitled State-of-the-Art Reactor Consequence Analyses, or SOARCA, as it was known in the NRC’s acronym-rich environment. The takeaway message from the panel: even if a severe nuclear power plant accident were to happen—say an extended station blackout at a Mark 1 boiling water reactor—it wouldn’t be all that bad.

The date was March 10, 2011.”

That was the day before the Fukushima earthquake and tsunami.

In fact, for decades, American NRC regulators did computer simulations that showed the GE Mark 1 reactor containment structures fail in station blackouts. These studies were not shared with Japan. The authors of “Fukushima” speculate that if they had been shared, things might have turned out differently because Japan followed the U.S. regulators’ leads more closely after the Three Mile Island accident in Pennsylvania in 1979. But the U.S. wasn’t pushing correctives in response to its own studies, and next-generation containment structures were not deemed much better under blackout conditions.

One week into the horror show, TEPCO upgraded the accident from level 4 to level 5, in a statement blaming the crisis on “the marvels of nature,” knowing that was just partly true. And the efforts of then-Prime Minister Naoto Kan and other officials to neutralize bad news to keep the public from freaking out were as constant as they were appalling. They had long overstated the safety of nuclear energy production, but with unknown amounts of radiation escaping after the accident, one might imagine that honesty and actual leadership would kick in. Guess again. Even after inadequate evacuations began, many citizens did not know why they were being evacuated, because they were not told.

In contrast to the example set by the establishment, endangered plant engineers and staff tried everything in their minimal powers to prevent the worst potential outcomes. Many worked without sleep for days at a time, and no essential employees opted to leave to save themselves. (There’s a parallel here to soldiers taking all the risk in wars started by government heads who stay out of harm’s way.) Early in the crisis, Kan ordered the shift supervisor to stop injecting seawater into the reactor at Unit 1, even though TEPCO management had already agreed that, due to the incapacity of freshwater pumping tools, cooling with seawater was unavoidable. (Seawater is highly corrosive, and Kan knew the action could signal how bad things really were.) Masao Yoshida, the supervisor, gave the monitored order but secretly told his crew to ignore it. The writers give these dedicated people due props for their tenacity and bravery, and the rebellious incident underscores the level of foolishness added to the obstacles.

The layering of facts, figures and physics makes the “Fukushima” reading experience a bit weedy, but a lot of information is needed to understand and follow events. The authors, who frequently jump back and forth in time, are challenged in presenting the timeline of the accident-induced traumas and management process clearly. The proliferation of acronyms throughout the book tested my memory, too, but some, like IDCOR, RASCAL, SARRY, and SPEEDI, add irony to a dry text.

And among the packed record that is often flattened with cliches are gems of history-as-satire, starring a cast of dunces with degrees. Two Swiftian examples: In 2005, a Japanese court ruled that the fault line near the Kashiwazaki-Kariwa plant did not exist, after a 25-year fight about location safety. Two years later, a 6.8 earthquake struck 10 miles offshore from the station. And during the Fukushima crisis, when it seemed clear that the radiation levels at the plant were reaching the allowable limits, the government considered raising the “safe” exposure level. With enough money on the line, any absurdity goes.

Despite its challenges, “Fukushima” makes a fine reference volume for understanding nuclear power production and its still-critical dangers. It’s also a mosaic of determined reconstruction, and serves as a play-by-play guide to What Not to Believe during an industrial accident. As the prescient journalist I.F. Stone warned for decades about governments: They all lie. And so it goes for most large corporations, whose PR shields give “spinning”—formerly known as lying—a shiny sophistication. Eight days into the crisis, Chuck Casto, the NRC rep in Japan working on no sleep and with little cooperation, said, “I’m just trying to figure out who the power player is over here.” This too is a crux of the story, and others about high-stakes arenas.

So life lessons abound here, but such lessons have been taught before by tragedies involving profit-driven risk taking: the Bhopal gas leak disaster in India in 1984, the Massey Energy coal mine collapse in West Virginia in 2010 and the Deepwater Horizon explosion/spill in the Gulf of Mexico in 2010, to name just a few. As I wound my way through this long saga about a short period in nuclear history, a refrigerator magnet from years ago kept coming to mind. Playing on a key line from the movie “The Sixth Sense,” it reads: “I see dumb people,” and provides an easy laugh. It’s unlikely that the educated people who helped make the Fukushima catastrophe worse are actually stupid, though they surely lack wisdom.

But if the difference in behavior and results is indiscernible, does it matter? ”

source

Shut California’s Fukushima: Diablo must go — Harvey Wasserman via EcoWatch

Harvey Wasserman warns the United States not to repeat mistakes made at Fukushima Daiichi and urges the shut down of the Diablo Canyon nuclear power plant in California.

” The catastrophe at Fukushima was not an accident. It’s unfolding again in California.

The next west coast quake could easily shake the two reactors at Diablo Canyon to rubble.

They are riddled with defects, can’t withstand potential seismic shocks from five major nearby fault lines, violate state water quality laws and are vulnerable to tsunamis and fire.

Diablo’s owner, Pacific Gas & Electric (PG&E), is in deep legal and financial crisis.

The California Public Utilities Commission (CPUC) has just proposed that PG&E be fined $1.4 billion for a 2010 gas explosion and fire that killed eight people and obliterated a neighborhood in San Bruno. The federal government has announced 28 indictments, meaning the CPUC fine may just be the tip of a very expensive iceberg for PG&E. The San Bruno disaster was caused by pipeline defects about which PG&E had been warned for years, but failed to correct. The fines cover 3,798 separate violations of laws and regulations, both state and federal. PG&E was previously fined $38 million for a 2008 pipeline explosion in Rancho Cordova.

Similar defects remain uncorrected at Diablo Canyon, whose radioactive cloud could span the continental U.S. in four days. Mass citizen action recently shut two coastal reactors at San Onofre. It must do the same at Diablo before the next quake hits.

Ironically, as America’s Nuclear Regulatory Commission (NRC) allows Diablo to operate, all 54 reactors in Japan remain shut. Its Nuclear Regulatory Authority has just ordered the Tsuruga reactor to be scrapped because of its vulnerability to earthquakes. Two more elderly reactors at Mihama may also be terminated before year’s end.

At Fukushima, Tokyo Electric Power now admits that far more radiation is spewing into the Pacific than previously admitted. The thyroid cancer death rate among children in the area is 40 times normal. So is the still-rising childhood thyroid abnormality rate, a terrifying re-run of downwind Chernobyl.

Tepco has begun paying compensation to local suicide victims, including the widower of a woman who doused herself with kerosene before burning herself alive.

All of it predictable.

For decades Japanese citizens warned Tepco not to build reactors in an earthquake/tsunami zone. The company repeatedly ignored safety warnings and tolerated known defects that worsened the disaster.

Diablo Canyon’s twin reactors sit eight miles west of San Luis Obispo, between Los Angeles and San Francisco, surrounded by earthquake faults.

The Hosgri, three miles offshore, was found as the reactors were being built. Design specifications were never fully altered to account for it. Nor have they been upgraded for the newly-found Los Osos, San Luis Bay and Shoreline faults. The Shoreline lies just 650 yard from Diablo’s cores.

The massive San Andreas fault is just 45 miles away, about half as far as was the March 11, 2011, Richter-9.0 epicenter from Fukushima.

A shock that size from any of the fault lines near Diablo could reduce it to a seething pile of radioactive hell, far deadlier than Fukushima. Prevailing winds could blanket virtually all of North America with its deadly fallout.

The nuclear industry would immediately deny all health impacts. It would blame “unpredictable” God and nature.

But a 42-page report from NRC inspector Dr. Michael Peck says new fault line discoveries challenge Diablo’s “presumption of nuclear safety.” … ”

continue reading

‘Fukushima’ sounds warning on nuclear energy – Los Angeles Times

” On March 18, 2011, an official from theU.S. Nuclear Regulatory Commission  named Chuck Casto called together the NRC delegation on assignment with him in Tokyo.

“We’re in never-never land,” he told them.

Seven days earlier, a magnitude 9 earthquake had rattled a complex of six nuclear power plants known as Fukushima Daiichi, roughly 150 miles northeast of Tokyo. Then came nature’s second, more devastating blow: a tsunami that swamped the complex, flooding its electrical generators and putting its three operating reactors out of commission. The reactors were soon out of control, the plant effectively disabled by that most feared event in the nuclear industry: a “station blackout,” when no power is available to run any of the safety systems designed to defend the public from a runaway reaction.

In the days that followed, three explosions blew apart portions of two reactor buildings, and the reactors’ fuel cores at least partly melted down. Public officials steadily expanded the evacuation zone around the plant, eventually to 19 miles; the evacuation of Tokyo itself was briefly considered.

“Never-never land” barely did justice to the situation. Casto and his team had been flown to Japan to help deal with the crisis, but all that they knew was that the Japanese government and Tokyo Electric Power Co., which owned the plant, were at an almost complete loss about how to deal with the catastrophe, as was the Japanese government.

Today, nearly three years after the event, only two of Japan’s 50 nuclear power reactors have been permitted to restart. The wrecked Fukushima station has been leaking radioactive water into the Pacific.

These events and more are meticulously reconstructed in “Fukushima: The Story of a Nuclear Disaster” by David Lochbaum, Edwin Lyman and Susan Q. Stranahan of the Union of Concerned Scientists. Followers of Fukushima and its consequences for the nuclear power movement have come to rely on Lochbaum and Lyman for their scientific expertise on the topic. Stranahan, a journalist and writer whose experience with nuclear power dates back to her coverage of the Three Mile Island accident in 1979, is evidently responsible for the book’s lucid and gripping narrative.

No one with an interest in the present and future of nuclear power in the United States should miss it.

Books and news coverage about nuclear power coalesced into three periods, roughly tracking the fortunes and self-image of the industry itself. First came the years of optimism, starting in the late 1940s and extending into the 1950s, when physicists and government bureaucrats alike were eager to spread the idea of the “peaceful atom” as counterpoint to the image of nuclear technology as a tool of war established by the bombings of Hiroshima and Nagasaki. The U.S. government heavily subsidized the nascent nuclear power industry, and General Electric and Westinghouse, manufacturers of the two leading power reactor designs, offered nuclear plants to a willing utility industry on loss-leader terms.

But reactor technology was vastly more complex than anything America’s utilities had dealt with previously. Their executives and their workforces were incapable of safely managing the willful atom. Meanwhile, the U.S. Atomic Energy Commission kept a tight lid on its own staff’s reports of the health perils of radioactivity loosed into the environment and the implications of runaway reactions. Anxious to tamp down public opposition to the novel technology, the AEC issued earnest reassurances about the rigorous safety standards of the nation’s burgeoning fleet of nuclear power stations.

By the late 1970s the truth was beginning to leak out, in part through the indefatigable efforts of the Union of Concerned Scientists, the home of the authors of “Fukushima,” which used the Freedom of Information Act to spring reams of documents from purgatory. The years of doubt culminated in 1979, when the Three Mile Island accident underscored the inadequacy of the “human factor” in managing power reactors. Over the next 10 years, plans for more than 60 nuclear plants in the U.S. were canceled.

But with the turn of the century, interest in nuclear power returned. Today the atom is treated as a potential “green” energy source. The managerial shortcomings of the past supposedly have been overcome, and the safety of the technology supposedly has advanced.

“Fukushima” is an indispensable reminder of the nuclear power industry’s failure to learn from the past. The assurances of greater rigor in the operation and regulation of the peaceful atom after Three Mile Island are contradicted by the flaws exposed by Fukushima. As Lyman, one of the authors of this book, observed in congressional testimony shortly after the disaster, a similar event could happen in the U.S. “We have plants that are just as old. … We have a regulatory system that is not clearly superior to that of the Japanese. We have had extreme weather events that exceeded our expectations and defeated our emergency planning.”

How safe is safe enough? Throughout the history of nuclear power, utilities and regulators have assured the public that their plants can withstand every emergency situation except the truly unimaginable. But the unimaginable can happen, as it did on the coast of Japan on March 11, 2011.

“Fukushima” shows in sobering detail what can follow when those with a vested interest in making the technology seem safer than it is decide not to plan for an extreme event because “it can’t happen here.” The authors remind us: Yes, it can. 

source