From Three Mile Island to Japan NO MORE NUKES!

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The powerful magnitude 9.0 earthquake that struck the northeast coast of Japan on March 11 has led to a cascade of disasters for the Japanese people. Its epi­ center was located on a subduction zone where the Pacific Plate is diving beneath the Eurasian Continen­ tal Plate into the Japan Trench. The earthquake was Ja­ pan’s most powerful and the fifth most powerful ever recorded globally.

The nation sits precariously on the edge of three tec­ tonic plates—the Pacific, Philippine and Eurasian— creating a triple junction of intense seismic activity. It is also located near the Median Tectonic Line, which consists of a series of strike-slip faults of horizontal movement. To build nuclear reactors where such ti­ tanic geological forces are at work is sheer suicide.

Because the quake was shallow enough, it caused the seafloor to heave up and away from Honshu Island, resulting in an enormous 10-meter (32.5 ft.) high tsunami that swept inland across the Plain of Sendai. The water was funneled through the streets of seaside port cities and towns three times higher and with even greater force, turning buildings along the wave’s path into piles of toothpicks.

The tsunami extended up to 10 kilometers (6 mi.) in­ land killing well over 10,000 people, with over 17,000 missing and 500,000 homeless. The northeast coast of Japan is particularly susceptible to tsunamis not only because of tectonic activity but also because of the many deep coastal embayments that amplify the waves and cause great inundations. This is another reason why the placement of nuclear reactors in the region was particularly foolhardy.

The human-made disaster The human-made part of the disaster is still unfold­ ing at the Fukushima Daiichi Nuclear Power Plant One, which consists of six boiling water reactors and seven spent fuel rod storage pools. Three of the reac­ tors were already in cold shutdown for routine main­ tenance. When the quake struck, seismic sensors tripped and activated the neutron-absorbing boron control rods to shut each core down in the working reactors. However, the residual heat from the nuclear piles, whose fissile byproducts continued to split and generate energy, still needed to be dissipated by the electrically-powered water cooling system. Moments later, the tremor felled the power lines that fed the water pumps. The backup diesel-powered generators automatically kicked in and powered the pumps.

Then, the tsunami struck, overflowing the plant’s woefully inadequate seawall and swamping the diesel generators. The next line of backup was a set of bat­ teries, which kept the pumps running for only a few hours before the reactors had nothing to cool them down. Oh, the irony of a power plant without power!

The only option of the plant operators was to pump in seawater with remote fire hoses to cool the reac­ tors. That worked for only a while. As pressure in the cores rose, the seawater evaporated faster than it could be pumped in, exposing the fuel rods to the air. At that point, they began to overheat, with xenon and krypton gas inside the rods exerting pressure, causing the zirconium alloy cladding to swell and crack. In ad­ dition, the increased temperature turned more water to steam, which had to be vented into the atmosphere outside. That steam was full of radioactive Iodine-131 and Cesium-137.

At the same time, the intense heat caused the zirco­ nium to interact with the steam and split some of the hydrogen away from the water. The hydrogen gas, set off by a spark, ignited in the remaining oxygen, and exploded. There were hydrogen gas explosions in all three reactors, which shattered the roofs and/or sides of the secondary containments. Reactor No. 3, which uses MOX fuel—plutonium/uranium oxide mix—has a long, vertical crack in its primary containment vessel. And the torus—the doughnut-shaped pressure-sup­ pression chamber—at the base of No. 2 is ruptured.

Because there was no functioning cooling system, hot spent fuel rods began to boil off the cooling water in their storage pools, which drained rapidly, expos­ ing the fuel assemblies. The storage pools are located haphazardly on a mezzanine above the reactors and are shielded by only sheet-metal siding, which is to say, they are not quake-proof. They contain 400 to 700 fuel rod assemblies stacked on racks.

After one year on-line, used fuel still emits 10 kilo­ watts of decay heat energy per ton and requires con­ tinual cooling under at least 30 feet of water. It takes only 140 hours for the water to drop to dangerously low levels with rods six months old. Roughly 100 hours after the quake and power loss, the storage pool of Unit 4, which has fresh fuel only four months old, experienced a fire because the zircalloy began to spon­ taneously combust like a Fourth of July sparkler. The oxidation reaction that occurs becomes locally selfsustaining at high temperatures.

According to David Lochbaum, director of the Nu­ clear Safety Program of the Union of Concerned Sci­ entists, the side of each storage pool has a gate, which opens to allow a crane to transfer spent rods from the reactor core to the pool underwater. The gates have (Above) Woman in Japan hears of relative’s death.

(Left) Three Mile Island, Pa., in March 1979.

inflatable rubber seals, but the air compressing sys­ tem that maintains them probably went down with the power outage. Consequently, the seals on the pools could very well be deflated, allowing the coolant to drain out.

There has been a constant struggle to pump water in to cool both the reactors and spent fuel assemblies. Efforts to do so by frantically injecting seawater laced with boric acid—boron, for its neutron absorption capacity—have not been successful. The use of the boron to moderate fission is a clear sign that fission is still occurring and some of the fuel has melted and slumped to the bottom of the containment vessels. Salt from the seawater has encrusted on the fuel rods and is insulating against the cooling effects of the wa­ ter, making for a wasted effort.

An enormous amount of radioactive water continues to leak into the turbine buildings, basements, outside trenches and into the sea. Obviously, the containments have failed. Former Three Mile Island nuclear engi­ neer Arne Gundersen, who calls Fukushima “Cher­ nobyl on steroids,” believes that there are partial melt­ downs underway and there has very likely been 7080% damage to the reactor cores because they went for so long without coolant. As a result, the radioactive molten slag lying at the bottom of the reactors is eat­ ing through the graphite seals on the control rods. The seals are also corroding from the extremely hot tem­ peratures and salt, hence, the large amounts of water escaping through damaged pipes into other areas. So now, they have the enormous task of pumping water both in and out.

Radiation levels are off the charts inside and outside the plant. The contaminated water in which workers are sloshing around measures at over 100 REMs per hour. Three or four hours at that exposure is a lethal dose. The deadly levels have made it nigh impossible for workers to access the system and get the runaway facility under control. The radiation spikes have inter­ rupted work many times. Plus, they must toil in small skeleton crews of 50 for very short shifts under con­ stant fear and duress.

According to an anonymous Japanese physicist, who spoke to The New York Times, many of the workers are subcontractors, who are paid a small daily wage to risk their lives, are poorly equipped and trained, and lack full protective gear. Pity them all and their poor fami­ lies. At least three have suffered radiation burns seri­ ous enough to be hospitalized. It is highly likely that there have been many more injuries than TEPCO, the utility that owns the plant, has reported to the media.

In addition to contaminated seawater, plutonium has been found in soil samples around the plant. The inhalation of one microgram of the isotope will kill. Because it is a byproduct of uranium fission, Gunder­ sen believes the plutonium probably volatilized in the zirconium fire in pool No. 4 rather than from the MOX fuel in Reactor No. 3.

The International Atomic Energy Agency (IAEA), an arm of the UN that functions largely as a booster for the global nuclear power industry, has sent two test­ ing teams to Japan. They reported radiation levels of 1600 times above natural background radiation (NBR) 12 miles from the plant. Constant exposure for (continued on page 7, in “Preventing imminent ecological catastrophe means shutting down capitalist institutions & ending capitalist rule”)

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12 SOCIALIST ACTION APRIL 2011 People have begun to protest in Tokyo and other cities because they know that nuclear power is not safe and the big utilities do not have their interests at heart.