Tuesday, December 30, 2014

In the thrall of a two-faced god

kw: book reviews, nonfiction, science, science and politics, history of science, radiation, short biographies

This post's title is taken from the last chapter of The Age of Radiance: The Epic Rise and Dramatic Fall of the Atomic Era by Craig Nelson. Nelson chronicles the discovery of radiation and radioisotopes, and development of various radioactive products, that began in the late 1800's. He carries through to the present day, in which more than 400 nuclear power stations produce about 1/7th of electricity worldwide, hundreds of radioactive isotopes are known and dozens are used for various medical and industrial purposes, yet several major power plant failures and the problem of accumulating waste from nuclear power plants has led to overweening public fear of anything related to the word "radiation".

Thus, I have observed that the "epic rise" and "dramatic fall" refer to public perception. Prior to 1945, radiation was extremely popular. Lying in a pool of radioactive water was supposed to be therapeutic. Even in 1960, when I was given a half-ounce of "yellowcake" (pure U3O8) powder in a gelatin capsule on a field trip to a Uranium processing plant, it was considered rather benign, and such "pills" were suitable gifts to a troop of Boy Scouts. Public hysteria had yet to set in. Trips to Las Vegas to see A-bomb tests were still popular, and would remain so until 1963. Even then, the end of air-blast testing was a result of a treaty with the USSR, not from public protest in America.

Nuclear waste became an issue primarily in America, because of a set of rather odd laws that prohibited reprocessing spent fuel from nuclear power plants. This is done as a matter of routine in Europe.

A side note for those who need it: Induced fission of Uranium or Plutonium results in "fission products". When a large nucleus is split because it has absorbed a neutron, it leaves behind two fragments (sometimes three) whose mass totals the original mass, minus the mass of two or more neutrons released during the fission event. It is kind of like a drop of water splitting into two smaller drops plus a few tiny droplets. These fission fragments are usually radioactive isotopes, typically with several excess neutrons, so they tend to decay quickly by beta decay, which converts neutrons to protons and balances the nucleus better. Several such decays will result in a stable nucleus. The trouble comes because some of the "quick" decays actually occur over months or years. These longer-lived isotopes accumulate in spent fuel from reactors, and as a result, it stays "hot" for thousands of years. Chemical processing can easily separate out these waste products, leaving purified Uranium or Plutonium, whichever "fuel" was first used. Purified Uranium is called "depleted Uranium" because the power-making isotope has been greatly reduced or eliminated. This stuff makes great bullets for snipers, being almost twice as dense as lead. Reprocessed Plutonium can be returned to the reactor as fresh fuel. Also note that reactors that use enriched Uranium are designed quite differently from those using Plutonium.

In the late 1970's there was a great debate going on about the safety of storing nuclear power plant waste. I was at a public event where a nuclear power industry representative described the materials. He said that the spent fuel from a certain kind of plant would be in a canister that looks a lot like a 50-gallon oil drum, but that it would initially be producing 10,000 watts of heat from the decay of fission fragments. This would decline to 5,000 watts over several hundred years, then be quite steady for thousands of years thereafter. I stood and asked, "May I obtain one or two to heat my crawl space in winter?"

Back to the book. The historical sketches and mini-biographies are invaluable. Dr. Roentgen, the Curies, Fermi, Oppenheimer and so many others are brought to life as rounded personalities in a way I have not read elsewhere. The glacially slow tragedies that prematurely ended the lives of nearly all early students of radioactivity are heartbreaking. It took much, much too long for scientists to realize that the energetic particles released by these isotopes were displacing electrons or atoms from their places throughout any material they passed through, including their own bodies. Such displacement did damage that frequently resulted in cancer or, at higher levels, radiation toxicity and even rather rapid death at the highest levels. A further note on isotopes:

An isotope is a form of an element characterized by a specific number of neutrons in the nucleus. Thus, all atoms of Oxygen have 8 protons in the nucleus, but the number of neutrons ranges from 4 to 18, giving them atomic masses of 12 to 26. The "usual" isotope of Oxygen, O-16, has 8 neutrons. Very small amounts of O-17 and O-18, with 9 and 10 neutrons, exist naturally. All other Oxygen isotopes are short-lived and only exist because of reactions in a nuclear reactor, and usually only when a scientist's purpose is to create them. The most stable of these reactor-created isotopes of Oxygen is O-15, with a half life of about 2 minutes.

The book's 17 chapters are in 4 sections. The first covers the early years up to 1938 or '39, and the second, the development of induced fission and the Manhattan Project that led to both Uranium and Plutonium bombs. One of each was dropped on Japan in 1945, and I can't help wondering if this was as much for experimental reasons as military. The third section covers the cold war, and the fourth, the early spread and more recent fallback of nuclear power generation and the power plant disasters that led to its fall from grace.

I was surprised to find out (I should not have been) that the meltdown at Chernobyl was only one of at least 10 or 12, and became known because it was close enough to international borders that its fallout plume was easily detected in other countries. The others had been successfully kept secret, even though one or two may have exceeded Chernobyl in total radioactive materials released and environmental damage.

The most difficult chapter to read through was the one on Fukushima ("Blessed Island" in Japanese). It is the best documented of the "big three" of the world's imagination, the other two being Chernobyl and Three Mile Island. The narrative exposes the monumental stupidity of the "designers" and "engineers" (they do not truly deserve those titles), who chose a reactor design known to be flawed; who chose to put it on a coastline prone to tsunamis and against clear warnings by geologists, and also in one of the more earthquake-prone parts of Japan—which is more earthquake-prone as a country than almost any other—; who chose to place the backup generators for the cooling system in basements that were at or below sea level; and then the host of errors that were made in operational safety measures during the weeks and months prior to the disaster. Actually, this was a series of linked disasters that played out over half a year's time, and in some measure they are still being played out.

But just as I was sure the author would inveigh against continuing use of nuclear power, he produced a string of facts such as:

  • The total death toll from nuclear power plant meltdowns, so far as is known, is 33,000 or less. This compares with 15,000 deaths over 30 years in the coal mining industry worldwide, and 20,000 in the petroleum industry.
  • The atomic bombs dropped on Japan killed roughly 200,000-250,000 within the first half year (half of those in the first minutes). An equal number were killed by the tsunami of 2004 in the Indian Ocean. Roughly twice this many die yearly in America alone from smoking-related cancer and heart disease.
  • A dam failure in China in 1975 killed 171,000.
  • On a per-megawatt-hour basis, fossil fuels are 18 times as deadly as nuclear fuels.

This is why Nelson calls "Radiance", the totality of industries and products of radioactive elements and isotopes, the two-faced god, like Janus. To moderns, the apt analogy is a two-edged sword. One daren't touch it anywhere but the handle! Yet public opinion is so strong, and the ignorance of scientific principles so profound in both public and political spheres, that atomic energy is effectively dead in America and a number of other "developed" countries, at least for the next generation or two.

Here is some final food for thought I came across as I considered this post:

This illustration went around and around the Web after it was published late in 2011. It shows the excess radiation exposure people are expected to receive by living in the various Japanese prefectures. The red-toned one is Fukushima Prefecture, and the exposure is 0.25-0.50 µSv/h. That unit needs explaining:
Unit: µSv/h - micro-Sieverts/hour. Radiation toxicity begins to make itself evident above a total dose of about 500 mSv (500,000 µSv), or half a Sievert, and more severe affects appear after 1 Sievert. About one person in 18 is expected to develop cancer if exposed to 1 Sv total over an extended period—for example, 115 µSv/h for one year.
It is hardly risky to spend much time even in Fukushima Prefecture. Lifetime exposure under an excess dose of 0.50 µSv/h would be about 2/3 of a Sievert. However, there are a few focal areas near the destroyed power plant in which you'd be very sick after spending no more than a few hours. If you want the thrill of visiting a nuclear wilderness, though, nothing beats taking a "nuclear tourism" tour of the Chernobyl area, where one can look into lands that are said to be too radioactive for people to live, but where wildlife flourishes without human interference, and one can even take a short walk over ground that cannot, by law, be built upon for at least 10,000 years.

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