Japan nuclear crisis passes Three Mile

NEW YORK, (Reuters) – Conditions at a stricken  nuclear power plant in Japan have deteriorated so much that  there is a growing consensus the crisis is greater than the  Three Mile Island accident in 1979, and there are fears that it  could get significantly worse.

Academics and nuclear experts agree the problems at the  Fukushima Daiichi reactors are grave, and the solutions being  proposed are last-ditch efforts to stem what could well be  remembered as one of the world’s worst industrial disasters.

All six reactors at the complex have problems — be it  blown-out roofs, potentially cracked containment structures,  exposed fuel rods or just the risk of explosion that has been  great enough to force emergency measures.

Of particular concern are a fire in a massive pool holding  spent atomic fuel rods and a blast at the building housing the  pool and reactor No.4. The pool is exposed to the elements,  unlike the reactor core protected in steel and concrete.

“I would say that it has now eclipsed the Three Mile Island  accident but it is not a Chernobyl,” said Keith Holbert,  director of the Nuclear Power Generation Program at Arizona  State University and an associate professor there.

The accident at the Three Mile Island nuclear plant in  Pennsylvania in 1979 was the biggest in U.S. history. Half of  the reactor core in one unit melted due to the loss of coolant,  though it resulted in no immediate injuries.

The Chernobyl accident in Ukraine in 1986 was the worst in  the industry’s history, as an explosion led to a cloud of  radioactive material being spewed over big parts of Europe.

Several experts said that Japanese authorities were  underplaying the severity of the incident, particular on a scale  called INES used to rank nuclear incidents. The Japanese have so  far rated the accident a four on a one-to-seven scale against  Three Mile at a five and Chernobyl at a seven.
But that rating was issued on Saturday, and since then the  situation has worsened dramatically.
In the past few hours alone, the plant’s operator Tokyo  Electric Power Co , said that a fire broke out at the  building housing the No.4 reactor — the same reactor that  houses the troubled spent fuel pool.

Kyodo News reported, citing TEPCO, that the fuel rods in the  No. 1 reactor were 70 percent damaged and the rods in the No. 2  reactor were 33 percent damage. Meanwhile, just after 10 a.m.  local time Wednesday, Japanese TV reported white smoke coming  from the plant.
“White smoke – meaning the steam release – would not  necessarily be a good thing,” ASU’s Holbert said.
Separately, Japan’s nuclear safety agency said two workers  are missing and disclosed that there is a crack in the roof of  the same building after an earlier explosion.

The International Atomic Energy Agency also said that TEPCO  has been considering the removal of panels from the No.5 and  No.6 reactors to prevent any hydrogen build-up. Such a build-up  has led to explosions at several other reactors in the complex  in recent days.

“This is a slow-moving nightmare,” said Dr Thomas Neff, a  research affiliate at the Center for International Studies,  which is part of the Massachusetts Institute of Technology.  “This could be a five or a six — it’s premature to say since  this event is not over yet.”

Experts said that international politics is starting to  become evident in the international pressure being put on the  Japanese. France’s nuclear safety authority ASN said Tuesday it  should be classed as a level-six incident.

“We are now in a situation that is different from  yesterday’s,” said ASN President Andre-Claude Lacoste.
An American nonprofit, the Institute for Science and  International Safety, went even further.
“This event is now closer to a level six, and it may  unfortunately reach a level seven,” ISIS said in a statement on  its website. ISIS founder David Albright is a physicist who has  published global catalogues of nuclear material.
Most, though, say the accident is still well away from the  massive explosion that hit Chernobyl.

SPENT FUEL
Of some concern is the decision to remove 750 of the 800  workers from the scene, as some questioned whether there would  be enough people left to tackle the growing list of problems.

“That evacuation is a sign they may be throwing in the  towel,” said Paul Gunter, director of Reactor Oversight Project  at the Beyond Nuclear environmental group. He said that so few  staff couldn’t possibly be expected to babysit six reactors in  the current conditions.
Though most people’s mental image of a nuclear disaster  involves a reactor cracking open or blowing up, scientists say  the biggest problem at the moment is the pools of spent fuel  that have lost water and caught fire in recent days.

“Up until now they have not been able to get close to the  spent rods, as even with protective clothing it only stops  workers from breathing in radioactive particles, not from  radiation itself,” said Peter Hosemann, a professor in the  nuclear engineering department at the University of California,  Berkeley.

Hosemann suggested, at least in the case of reactor No. 4, a  crack in the roof may actually ease access to the pools and give  the Japanese the chance to cool the pool by air-dropping water  on the reactor from helicopters.
That they have to resort to air-dropping, though, points to  breakdowns in the system that industry executives say should  have been easily prevented.

“People literally probably did not know this was happening,  either the instruments were wrong that were measuring the water  level, were damaged in the earthquake, or they literally had  people scrambling dealing with so many other problems at the  plant they had no one’s eyes on the level of the water in the  spent fuel pools,” said Seth Grae, chief executive of nuclear  consultancy LightBridge Corp.
“My guess is that if they had, they could have dealt with  this before it ever became a big problem … we’re literally  talking about a hose.”
Whatever the solution, the resolution is bound to be  prolonged. ASU’s Holbert and others said turning off a reactor  only starts to end the problem.

“It’s going to be a long end-game because they are going to  have to keep cooling in there and they will have to rig up  something for the longer term,” said Elmer Lewis, professor  emeritus of mechanical engineering at Northwestern University in  Illinois.