Sunday, March 13, 2011

A Complex and Uncertain Story: The Importance of the Japanese Reactors

In trying to decipher the conflicting reports over the Japanese reactors, the most important single point to understand is this:  nuclear issues are complex and uncertain – they defy short simple explanations.  For example, the outcome of an event in a reactor built over a water table 50 feet deep might be entirely different  if the same reactor were built over a water table 350 feet deep.  Radioactive particles that can be brushed from your skin without danger might cause a horrible death if you swallowed them. Different people might react quite differently to the same dosage of radiation. What gives one cancer might not affect the second at all – and might cause a genetic defect in the children of a third. The situation is ripe for dueling 60 second messages on TV, and is likely to leave audiences confused and skeptical.
Additionally, despite official pronouncements, we do not know the actual status of the reactors in question.  Is the sea water used for emergency cooling being contained, or running back to the ocean with its load of radioactive materials?  We just don’t know.  But here are some things we do know.
First – how the reactors in question work.  Left to itself, the specially blended radioactive “fuel” in reactors gets very hot. Water cools this heat and in the process is converted to steam which spins turbines with its high pressure. The turbines spin generators that make electricity. In the process the steam is cooled back into water that goes back into the reactor to cool it again, and again be converted into steam for the turbine.
This system is quite clean and quite safe. 
·         As long as the decayed fuel “waste” is disposed of.
·         And as long as the closed loop of fuel and radioactive water is not breeched by attack or accident.
Concerning Waste:  At nuclear power plants waste is held underwater in a “cooling pond” until it can be collected and buried deep in a safe location. In the US, one location (Yucca Mountain in Nevada) has been certified and prepared for such waste storage at a huge taxpayer cost. But Senator Harry Reid of Nevada has blocked use of the facility.  So waste is building up in cooling ponds nationwide. In Japan, the status of the cooling ponds at the damaged reactors is unknown. 
Concerning Accidents:  Western designed nuclear power plants have multiple redundant safety features.  In a crisis, “control rods” that absorb energy and reduce heat and power are quickly and automatically inserted. Additional pumps driven by special back up systems kick on automatically to provide additional cooling water. A double walled “containment faculty” keeps pressure in check around the hot core. Multiple other highly reliable systems surround the critical parts of the reactor.
Concerning Attack:  All the critical elements that protect against accident receive double security against attack.  The famous containment “domes” that mark many plants are safe against any but the most direct attack by penetrating bombs available only to nation states.  Pipes, pumps, etc. are protected from ground attack by platoons of specially trained security forces.  Drills are conducted frequently. No defense is foolproof, but the defense of nuclear power plants comes pretty close.
HOWEVER – Human error is always a concern. It cannot be completely eliminated. For example, at Three Mile Island, faulty sensors caused operators to react inappropriately and override the automatic safety systems.  And at Chernobyl operators made even greater mistakes, shutting off safety systems to “test” them, without the robust protective measures of Western reactors.
The problems of accident and error may be compounded when multiple crises cause multiple failures. Measures adequate for even the strongest earthquake (like back up pumps, communications, and generating systems) may fail in the face of a tsunami. And plans for a tsunami may count on outside experts and supplies not available when an earthquake (or a storm, or a volcano, etc.) isolate the site of the disaster. When cascading failures raise unanticipated problems, spur of the moment solutions (like pumping in seawater) may turn out to be errors that cause unanticipated consequences of their own.
And an attack can be worse because an adaptive enemy may be working as hard to frustrate your emergency plans as you are to put them in place.  For example, they might ambush experts coming to help, delaying response and  destroying irreplaceable  expertise.
Well what is the range of problems experts are dealing with in Japan?  How bad can it get?  Please see paragraph two  above:  nuclear issues are complex and uncertain – they defy short simple explanations.” 
The good news is that even in the worst case, this is not likely to look like Hiroshima – that’s not what a meltdown does.  The bad news is that in the best case some radiation is going to hurt somebody, impact life in other countries, and cause an intense, scary and emotional debate about the future of nuclear power .  Advocates are likely to lose. The price of oil, gas and coal will jump as a result.
To provide a bit more detail:
·         In the best case, some radioactive vapor has already escaped into the atmosphere, ash from a containment explosion has drifted downwind, and seawater is washing over a radioactive core to cool it.  Where to you think radioactive vapor, particles and seawater are going? Nobody is going to be producing food, drinking milk, or eating fish from impacted areas for a while.  After Chernobyl, “impacted areas” included many far away countries.
·         In the worst case, the core will be exposed, burn at 5000 degrees Fahrenheit, pass through the cement building holding it, the rock below, and eventually hit ground water where a flash steam explosion might distribute it for thousands of miles (if particles are picked up in the upper atmosphere).
At least for now everyone (including the press and even anti-nuclear groups) is holding off on hysterical pronouncements, because they also know that  nuclear issues are complex and uncertain – they defy short simple explanations.”    But make no mistake, despite being wrong, the short simple explanations will be coming from both sides.  Unless pronuclear forces launch a very clever and convincing campaign, the scary “it could happen here” pitch is likely to win.  And that means a big reduction in power available in the US and elsewhere, along with a big price increase for all other energy.
No matter how this story turns out for Japan, the strategic implications for the US are expensive.
To donate to disaster assistance contact .

No comments:

Post a Comment