Archive for Fukushima

Uncertainty at the Core of Nuclear Crisis

Posted in Events, Japan, Technology with tags , , , , on March 16, 2011 by Matt Hutchins

An utter catastrophe is presently unfolding in Japan as the nuclear reactors at the Fukushima Daiichi facility that were crippled by the Sendai earthquake and tsunami are believed to have suffered severe containment breaches and fuel damage in a series of explosions.  Uncertainty has permeated all aspects of the situation now, including the extent of the damage to the containment vessels, how much the radioactive fuel in the reactors has been damaged, how fires in the spent fuel storage will be contained, and the degree of danger to nearby populations from radiological release.

Fifty brave workers have remained at Fukushima to continue battling the chaos regardless of the personal danger, and the whole world watches, wondering whether these workers and other outside experts can succeed in crafting a response to the situation that will control its broader consequences.   But other questions of serious importance also hang over the ongoing crisis.  Already there has begun a global debate about whether the catastrophic failure of cooling at Fukushima calls into question the future of nuclear power around the world.  In the face of such a terrible set of disasters and a crisis that is beyond our control, people everywhere are struggling to restore a sense of stability by explaining these events within our broader historical narrative.

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The risk of a catastrophe, whether in nuclear power or otherwise, is inherently difficult to estimate.  If adequate information were available to estimate the possibility of a catastrophic event, then we would be able to use that information to prepare for the event and avoid the catastrophe.  Thus, in a certain sense, the definition of a catastrophe is an event that exceeds all reasonably expected risks and destroys the fabric of the reality we created within prior expectations.

The disaster that struck Japan on March 11, 2011 was by any realistic estimation an utter catastrophe, out of proportion to what could have been expected to occur based on history and science.  The earthquake which hit first was a 9.0 on the contemporary momentum magnitude scale, an order of magnitude more powerful than the 8.5 quake which some appear to have expected was possible.  The tsunami which then followed struck with an overwhelming and indiscriminate force that, expected or not, was beyond all human capacity to avoid.  Although the Japanese have lived in constant awareness of their vulnerability to earthquakes and tsunamis, these events unfolded with such violence that all preparation was nullified.

The nuclear crisis which has now followed therefore rests within the context of an extraordinary blow which was dealt by natural forces.  Nonetheless, the situation at Fukushima Daiichi remains one for which mankind must assume responsibility.   As early as 1972, there were serious concerns about the vulnerabilities of early designs for boiling water nuclear reactors, such as the Mark I systems at Fukushima, that rely on active cooling systems to maintain stable core temperatures.  It is for this reason that reactors being designed and commissioned today rely on passive cooling systems that do not depend on activation by operators or powered controls and that will assume a safe equilibrium in the absence of external sources of cooling.  Despite safety concerns, reactors like those at Fukushima, designed over a half-century ago, have remained in service, partly because of their historical track record of safety and partly because of the continuing need for their power output and economic benefit.

Now the fabric of the reality which had been constructed around the safe operation of these nuclear reactors is rapidly disintegrating.  Their removal from the power grid has already begun a severe disruption in the availability of electricity in Japan’s largest cities, including Tokyo.  The specter of radioisotopes descending on these cities is driving consumers to stockpile necessary goods and seek to escape to distant safety.  The creation of an exclusion zone is forcing many to leave their homes behind, uncertain when or even whether they will be allowed to return.  And financial markets are losing confidence in the ability of the nation to overcome the challenges it faces, including massive costs for relief and reconstruction as well as tremendous loss of economic output.

The media has enjoyed unprecedented access to updates about the ongoing developments as the situation has deteriorated at Fukushima.  Direct video by helicopters, live satellite images, multiple press conferences each day by plant operators and the government, and considered commentary by experts has made this nuclear incident far more public than any prior incident of comparable severity.

But despite the openness of communication and access, uncertainty has generated frustration throughout the crisis.  There has been some of the inevitably defensive behavior by the plant’s operator, Tepco, which must be expected.  After all, scientific experts whose careers have revolved around preparing for such an incident would like to believe themselves capable of handling a crisis with professional demeanor.  There have been minor cases of minimizing the severity of damage and overstating the expectation of being able to control the situation.

However, the much greater cloud of uncertainty which appears to have limited the availability of information is one which emanates from the dangerous and chaotic situation at the Fukushima Daiichi facility itself.  The initial damage caused by the earthquake and tsunami have been compounded by aftershocks, equipment failure, explosions, and extreme conditions that make it impossible to physically intervene and prevent further deterioration of the situation.  Moreover, each successive failure of containment and emission of radiation has foreclosed the possibility of providing even routine stabilization to the remaining reactors and spent fuel stockpiles.  Thus, even the basic information gathering necessary to assess the situation to prepare a coordinated response has been lacking in part due to the impossibility of action.

Outside assistance to the operators of the plant has been limited by both the hazards of exposure to radiation and harmful isotopes and the logistical hurdles created by the earthquake and tsunami.  At this point, the potential lethality of the current conditions and the limited options for intervention make it difficult to imagine how outside forces can stop the effects that have been set in motion from playing themselves out while the world watches.

We will all hope and pray that science and government can muster an innovative response that will limit the harmful consequences of this disaster, but we should remember that it was our faith in science and government which allowed this situation to be created.  Just as the Deepwater Horizon oil incident showed us last year, once frightening technological forces escape human control, it can be an extreme challenge to restore our grip on a dangerous situation.  Faith in technology must be tempered by pragmatic risk assessment.

There are many in the media and politics who have already begun exploiting this moment to cast criticism upon the safety of nuclear power and to call for a halt to planned or ongoing nuclear projects.  To those people I would say that this event has changed nothing.  The nuclear industry knew from its beginnings that a catastrophic failure of this sort was possible, and danger was proven to be a reality by numerous incidents, the most notable of which is the Chernobyl reactor’s devastating explosion.  The public has had a duty to hold regulators and industry to their duty of stewardship since the emergence of atomic power, and although a crisis gives us cause for consideration, this particular incident is no more than a severe example in reality of something already well understood in theory.

The most startling aspect of this event is that unlike previous major nuclear power incidents, this accident was not directly caused by operational errors.  As of 2 p.m. Tokyo time on Friday, March 11, 2011, the Fukushima nuclear facilities were apparently in full compliance with regulatory requirements that were neither lax nor ill considered.  But just like the hapless residents of the Japanese coast who were swept off by the tremendous tsunami, the risk assessments by the experts involved in licensing these facilities were overwhelmed by unforeseen events.

The exact same problem as occurred here has been at the center of the long delays and debates regarding the efficacy of constructing a central repository for nuclear waste at Yucca Mountain in Nevada.  To the credit of U.S. regulators and legislators, the delays have been at least partly based on the refusal to approve a project that involves a real risk of a terrible catastrophe in the distant future.  Scientists have been unable to mathematically eliminate the possibility of future release of radioisotopes into the environment due to the fact that the Yucca Mountain site is geologically active and has had major earthquakes, volcanic activity, and significant climate-change related variations in hydrology over the relevant geologic time horizon.  A faulty assessment of the risks involved in storing all our nation’s spent fuel at the Yucca Mountain facility would potentially threaten the habitability of the entire planet because once storage is complete the site would be beyond the possibility of repair.

Because of the risk of catastrophic failure, Yucca Mountain, requires us to exercise extreme caution to avoid the sunk cost fallacy.  No matter the enormous cost to date, taking the final step of setting such a facility into action is an irrevocable act that should only be taken if the risk being undertaken is justifiable.

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At Fukushima, the greatest immediate risk of serious radiological release appears to stem from the spent fuel, which is stored in pools of water that are rapidly boiling away.  The decision to store the fuel in this manner epitomizes the hubris of the nuclear industry, as it rests on the assumption that experts will remain engaged in the monitoring of the fuel and will have the technology at their disposal to ensure proper cooling as long as is necessary.  But now we are seeing that due to cascading failures and unexpectedly overwhelming forces, human control of a dangerous situation cannot be relied upon in the design of any system that poses an inherent danger of instability.

It is for this reason that the effects of the natural disaster which struck Japan are now cascading from failure of cooling systems to reactor core failure and now to the potentially more serious damage to the uncontained spent fuel stockpile.  As each domino falls, the reliance on human control at each stage in the process is exposed as a flawed premise in the safety design.  There is inherent uncertainty in whether human intervention will always be possible or whether, given an unexpected situation, operators will have the information needed to carry out an effective response.  Indeed, the decision to pump sea water into the Fukushima reactors may yet be shown to have only exacerbated the risk of the explosions that are currently believed to have breached the containment systems of two reactors.  Was the injection of water appropriate given the risk of releasing hydrogen?  Did the salt content of sea water interfere with cooling further or cause unexpected chemical reactions?  Allowing a meltdown may ultimately be shown to have been the more prudent course once the cooling systems failed.

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At the present moment, the public should support the efforts of government and experts to rapidly contain the crisis and provide relief to those in Japan who are being displaced by the nuclear and natural disasters.  We should all pray that those brave fifty who have remained at Fukushima can endure the test they are facing until ingenuity, effort, or fate brings them relief.

Already there is a clear lesson: the reliance on human intervention to control dangerous technologies cannot be considered a sufficient check against catastrophic failure.  In the face of such risks, scientists should not minimize the possibility that their own wisdom would fail to account for unforeseen circumstances and cascading failures.  The public should be inquisitive and pragmatic in evaluating proposed projects and remain skeptical of the promise of benefits at the margin, because when private endeavors fail catastrophically it is the public that will ultimately bear the cost of containing the damage.  And where damage from the chaotic release of great forces  spills over into society, all of humanity must hold innocent and have solidarity with those individuals who have been drawn under the wheel of catastrophic events.

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