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The total human impact of the Chernobyl disaster on human lives in the next 100 years will be difficult to measure. As many as 4,000 cancer cases due to fission-product uptake are predicted.

Even though the power-plant complex was badly damaged and littered with debris from reactor No. 4, the electrical needs of Ukraine were such that reactors No. 1, 2, and 3 were kept running. No. 3 was the last to be shut down permanently, on December 15, 2000. A sarcophagus made of concrete 660 feet thick was poured to cover up the remains of reactor No. 4. The radiation exclusion zone around the complex is a nature preserve, now populated with animals that had lived there before mankind cleared the land and built structures on it. In the deepest recesses of the destroyed reactor in a field of heavy mixed radiation, a new form of black fungus has found it a nice place to live. It seems to love the lack of competition for the space.

It seems unfortunate, but nothing was learned from the Chernobyl disaster. It did not, for example, lead to a better understanding of reactor accidents or an improvement in reactor design. At the time of the catastrophe, the graphite boiling-water reactor design was already history in the West, and its obvious mechanical flaws and lack of operational knowledge were two trains heading to collide on a common track, and the isolation that the Soviet engineers operated within was in large part to blame for this fundamental flaw in the plant’s design.

The causes of the Chernobyl-4 disaster were complex, reaching deep into the social, political, and economic structure of the Soviet Union, and it was most likely a component of the complete collapse of this government four years later. It could theoretically have been avoided, but that would have required a complete rebuild of Soviet attitudes toward building the future, fiercely competing with the rest of the world, and placing value on the individual citizen. Such changes would begin to come about, but not before the Chernobyl reactor’s self-destruction had deeply wounded the industrial fabric of the Union of Soviet Socialist Republics and embarrassed it to the rest of the European continent and beyond.

From what the Western nuclear engineering community could tell, the big Soviet graphite reactors were of questionable design and likely to give trouble. The Soviets had their own way of accomplishing engineering goals, and they were not necessarily open to contemplate negative Western opinions. Conversely, we were not interested in their opinions of our nuclear power systems.

The next disaster, though, would involve American engineering, and there would be no excuse for it. Events started tumbling toward disaster at 2:46 on a Friday afternoon, off the northeast coast of Japan.

Chapter 10:

Tragedy at Fukushima DaiIchi

“HEAT SINK: a small metallic device attached to your CPU that, like the cooling tower at a nuclear-power plant, is the only device standing between safe, reliable system operation and a total core meltdown.”

— Howard Johnson, Ph.D., in Manager’s Guide to Digital Design

It would be difficult to think of a worse place to build a nuclear power plant. Perfectly safe nuclear generating stations have been built in hazardous locations from Antarctica to the Greenland glacier, but putting one on the beach in Japan, looking out over the ocean, right there on the Pacific Ring of Fire, seems ill-advised. The Ring of Fire, encircling the entire Pacific basin, including the California coast, is under constant threat of earthquakes, tsunami waves, and volcanoes from the westward tectonic shifting of the North and South American continents.

The nuclear engineers, mechanical engineers, civil engineers, electrical engineers, and seismic specialists in Japan are well trained and experienced, and they know how to optimize a building project. That is why, for the 54 nuclear reactors that were recently generating 40 percent of the electrical power in Japan, there is not one cooling tower. Why build natural-draft, fog-making, hyperboloid cooling towers, 600 feet tall, when you can use the Pacific Ocean as the ultimate heat sink for your generating plant? It saves a lot of space, which is precious in Japan, a lot of concrete, construction time, and money.

Every nuclear plant in Japan is built on the coast. Those in the southwest of the main island of Japan, Honshu, where the electricity alternates at 60 hertz, stare into the Sea of Japan. Those plants in the northeast of Japan, where the electricity alternates at 50 hertz, overlook the subduction zone where the Pacific tectonic plate runs underneath the Okhotsk tectonic plate.[257] As the North American continent glides westward on the slippery, molten rock on which it sits, the Pacific Ocean gets smaller and smaller, the Atlantic Ocean gets bigger and bigger, and the Pacific Plate subducts under Japan at a blistering 3.6 inches per year. It is not a smooth movement. The Pacific Plate sticks to the Okhotsk as it tries to fold under, and it can hang, not moving, for a thousand years as the tension builds up. Finally, the situation between the plates is stressed to the breaking point, and it just lets go, all of a sudden, in the rocky depths miles below the bottom of the ocean off the coast of Japan.

The shock wave produced by this abrupt movement travels fast through the rock, and it hits the Japanese islands with more force than any atomic bomb could produce. Things sticking up out of the ground are sheared off as the Earth underneath suddenly shifts position by measurable feet. Destruction is widespread as the entire island shakes.

Moving more slowly, the second shock wave moves as an enormous ripple in the ocean water, beginning over the point undersea where the plates slipped and moving in a circle of growing radius. As the ripple nears the shore, the water gets shallow, and the shock wave, distributed evenly in the liquid, gets funneled down and concentrated. The amount of energy is still there, but there is less and less fluid to hold it. The ripple becomes a monster wave, and it hits the shore as a wall of water, the tsunami, coming very fast. It finishes off anything that was not knocked down by the initial shock wave through the ground and inundates inland territory.

That is why there are better places to build a nuclear power plant than on the beach in Japan, which would seem evident from the remains of what was once a roughly semicircular pattern of ancient, inscribed rocks, planted upright in the ground a few miles from the shoreline in northeastern Japan. These monoliths, probably 600 years old, are all graven with the same message, written in a long-forgotten Asian dialect. Scholars pooled resources for centuries, trying to decipher the message, seeing success some 30 years ago. Very roughly translated, the inscription reads: “Don’t even think about building anything between here and the ocean.” A thin layer of water-borne silt underneath the topsoil, ending about where the stones are placed, attests to the fact that a tsunami wave once washed this far inland.[258]

The secondary cooling in a Japanese reactor is breathtakingly simple. A concrete pipe extends for a couple of hundred feet out into the ocean from a pump stand on the beach. A screen keeps curious sea life from being drawn into the cooling process. Water is sucked in by the pump, circulated through the condenser in the floor under the steam turbine, and introduced back into the ocean at a point a few hundred feet farther up the coast. A cooling system could not be any less expensive to build.

The quest for nuclear power in Japan began in 1951. The centralized state-run power company, established for national wartime mobilization in the last Great War, was formally dissolved, and nine small power companies were formed. One was the Tokyo Electric Power Company, Incorporated, now known as TEPCO, formed on May 1, 1951. Its territory was the upper eastern section of Honshu, the main island, operating on 60 hertz current.

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In the early 20th century, Japan wanted to step up to electrical power, just like everyone else in the developed world, but there were at least two modes of alternating current in use. Europe had chosen an alternating frequency of 50 hertz, and America had chosen 60 hertz. Japan, still recovering from centuries of non-centralized government using the warlord model, found that the south end had chosen to buy generating equipment from Westinghouse, and it all ran on 60 hertz. The north end, on the other hand, had bought equipment from Siemens A.G., and it ran at 50 hertz. The two transmission modes are incompatible, and the north-south divide of electrical current exists to this day. In a broad emergency, this discontinuity makes it difficult to ship electricity from an undamaged southern end to the devastated northern end of Japan. A small number of frequency-converter stations exist on the boundary, but their capacity is overwhelmed in a disaster.

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There have been many recorded earthquakes originating off shore that caused tsunami destruction in Japan. The one referred to on the “tsunami stones” is probably the Jogan Sanriki earthquake, which occurred at the Pacific/Okhotsk subduction zone on July 9, 869 (the 25th day of the 5th month, 11th year of Jogan). Its magnitude is estimated at 8.6. The existing stones may be replacements for original warnings that eventually became unreadable due to advanced age.