Finding a Solution to Nuclear Waste: A Policy Analysis

Description of the Problem

The first issue is to understand the significance of nuclear waste. Yim and Murty (2000) provided a primer on nuclear power and on the basics of nuclear waste.  Nuclear power plants operate much like any other power plant. The nuclear generator produces an excess of heat which is used to boil water. That water turns to steam which turns the blades of a turbine, and that generates electricity.  The only fundamental difference between a nuclear power plant and a fossil fuel power plant is that the source of the heat in a nuclear power plant is a nuclear chain reaction; in a coal- or oil-fired plant, the heat comes from burning a fossil fuel. During the nuclear reaction, the fuel rods in the generator undergo a fission reaction in which the uranium splits into two lighter elements, releasing heat plus some free neutrons which in turn cause other uranium atoms to split (thus initiating a chain reaction that is self-sustaining).  (Yim & Murty, 2000).

Because a nuclear generator uses very highly radioactive elements, the level of radioactivity of the waste is also highly radioactive and for a very long time.  The fuel is most often uranium and sometimes (as with Fukushima Unit 3 reactor) plutonium. The half-life of plutonium 239  is about 24,000 years.  Typically, it takes ten half-life cycles for radiation to reduce to a tolerable level. Thus, plutonium fuel must be stored for approximately a quarter of a million years—a period about fifty times longer than all of human written history.

Even after the fuel rods in a nuclear reactor are “spent” only about 5% of the uranium in the fuel has undergone fission to transmute into daughter elements. The remainder of the uranium is still present. Furthermore, some of that uranium does not undergo fission, but instead absorbs a neutron (a by-product of the fission of other atoms of uranium), which causes it to transmute to plutonium.  Thus, the fuel rods, even after they are considered spent, are dangerously radioactive, with a complex mixture of elements such as uranium, plutonium, cesium, strontium, iodine, and others (Gunderson, 2011).

Rogner (2010) noted that radioactive waste is designated as low level, intermediate level, and high level. The first two categories derived from civilian, hospital and research type applications, and is routinely disposed of in licensed facilities. The third type, high level waste, generated from civilian nuclear power plants, has no current method of disposal, so it is routinely stored on site, typically in “spent fuel pools”; this amounts to about 11,000 tonnes of fuel per year that must be stored and guarded against theft or accidental exposure of the public to the dangerous radiation.

Gunderson (2011) noted that the efficiency of nuclear power plants can be viewed from two perspectives. In the near term, nuclear energy is highly efficient because it takes only a modest amount of fuel, about what might fit in a two or three semi-trailer trucks, to operate the power plant for an entire year.  In contrast, a coal-fired power plant requires a trainload of coal every day to stay running (Gunderson, 2011).

Yet when considered in a larger perspective, the efficiency and “cleanliness” of nuclear power isn’t nearly as great at that limited perspective indicates. For example, nuclear power plants are forced to operate at lower temperatures, typically only 600 degrees, than coal- or oil-fired plants which operate at far higher and more efficient temperatures. This is because at temperatures above 600 degrees the nuclear fuel rods begin to melt.  This also means that much of the heat the nuclear reaction produces in the radioactive steam is simply wasted (Gunderson, 2011). The excess heat is cooled by external water from a nearby river, lake, or ocean, which, though physically isolated from the radioactive steam, eventually transmits that excess heat into the environment, usually by flushing the heated (but not radioactive) water into a river or ocean nearby.  This means that in terms of thermal pollution, nuclear power plants are 40% more thermally polluting than a coal-fired or oil-fired plant. In a very real sense, the newest form of power generation, nuclear power, is the least efficient form of power generation we have (Gunderson, 2011).

Another issue is that the source of fuel for nuclear power plants is a problem.  Uranium mining  not only generates the same types of open sores on the landscapes as coal pit-mining, it also subjects the miners to distinct personal safety problems due to handling naturally radioactive ores. Even worse, the quality of available uranium ores has declined precipitously. The Congo is the original source of much of the uranium ore in the world.  When initially mined a half-century or more ago, the ore contained about 1% uranium, containing about 20 pounds of uranium in every ton of ore.  Today’s ores contain only 0.01% uranium; thus, a ton of rock, 2000 pounds, from the uranium mines contains only about 0.2 lbs, or about 3 ounces of actual uranium—and the density of uranium is still declining.  The Jordanian Desert is another potential source of uranium ore—but it contains only 0.001% uranium. Despite the poor yield, it is considered a potential source for the future of uranium to feed nuclear reactors (Gunderson, 2011).

The other obvious problem is that the results of the burning fuel in a nuclear power plant have not one, but two dangerous characteristics.  First, they are themselves radioactive, and they stay radioactive for up to thousands of years.  Cesium byproducts of a nuclear generator have a half-life of about 30 years; strontium byproducts  have a half life of about 30 years, but plutonium, also a byproduct of nuclear power generation, has a half-life of 24,000 years.   If ingested (either through food or water contamination or inhaled), cesium tends to amass in muscles, including the heart, causing muscular problems and a new type of heart disease first noticed after Chernobyl 25 years ago. Strontium tends to mass in the bones and bone marrow, causing problems with various types of cancer, leukemia, and the like. Plutonium is so incredibly poisonous if ingested that a fraction of a gram will kill (Gunderson, 2011).

This means that these byproducts have to be safely stored for centuries (in the case of strontium and cesium) and for hundreds of thousands of years in the case of plutonium.  Second, they are also physically hot (i.e., at extremely high temperatures), and they stay physically hot literally for years, something that was not fully appreciated until the Chernobyl disaster a quarter century ago.  The reason they stay physically hot for so long is that the amount of heat is huge, and it is contained in a relatively small space, protected by cooling waters (except in the case of accident as in Fukushima), but cooling only slowly.  Thus, shutting down a nuclear power plant does not eliminate the heat issues, or even the radiation issues. (Gunderson, 2011).

Yet another aspect of nuclear waste is that not only does the environment have  to be sheltered from this extremely dangerous material, but the waste itself has to be guarded from people who may want to steal it for use as a weapon.  Because the nuclear waste contains plutonium, a component of nuclear weapons, it is just as important that any waste storage facility be protected from theft, incursions or other nefarious activity (Gunderson, 2011).

Thus, a solution to nuclear waste has to be able to cope with tens of thousands of tons of physically hot, highly radioactive material, but also must take into consideration the wasted areas of the mining efforts, and the excessive heat pollution generated by the nuclear power plants, plus the need for ongoing security for millennia.