Yucca Mountain Is Designated a Radioactive Waste Repository

Date December 22, 1987

The U.S. Congress created controversy when it named Nevada’s Yucca Mountain as the first permanent U.S. repository for nuclear waste.

Locale Yucca Mountain, Nevada

Key Figures

• Jerry Szymanski (fl. late twentieth century), geologist for the U.S. Department of Energy
• Richard Bryan (b. 1937), governor of Nevada, 1983-1989, and U.S. senator, 1989-2001
• Carl Gertz (fl. late twentieth century), U.S. Department of Energy scientist in charge of the Yucca Mountain project

Summary of Event

Nuclear power and nuclear weapons are both produced in nuclear reactors. At the heart of all such reactors are large groups of twelve-foot metal tubes filled with pellets of uranium fuel. The average electricity-producing commercial nuclear reactor contains thousands of such tubes, joined into bundles called fuel assemblies. In nuclear reactors, the uranium fuel undergoes nuclear fission, which produces energy in the form of heat. This heat converts water into steam, which runs large steam turbines and produces the desired electricity. The nuclear fission process also converts every reacted uranium atom into highly radioactive—and thus very dangerous—fission by-products called radionuclides. Radionuclides deposit at the surface of the uranium fuel in fuel assemblies.

The process proceeds satisfactorily in a reactor for three to four years, until its fuel assemblies, as a result of surface radionuclide deposits, can no longer sustain enough nuclear fission to produce the needed amounts of electrical power. At that time, the assemblies become spent fuel. Spent fuel, which is rich in dangerous plutonium, strontium, barium, and cesium radionuclides, is then pulled out of the reactors and stored underwater in cooling ponds situated near the reactor from which it came.

These ponds use circulated water to keep radiation from spent fuel from entering the environment and to prevent the heat that is still produced by nuclear fission in the spent fuel from causing explosions. The ponds are, however, an imperfect solution for by-product storage for several reasons, the most important of which is the fact that hundreds of pond sites are located close to major U.S. population centers. A desired solution to the problem is the safe storage of all the nation’s radiation in spent fuel at one or a few sites that can sequester this material safely inside nuclear-waste repositories for the one hundred centuries required for the waste to become harmless.

The U.S. nuclear electric power industry and armed forces weapons research produced an estimated 100 million pounds of nuclear waste by the beginning of the twenty-first century. At least three-fourths of such waste comes from the power industry. In 1982, the U.S. Congress passed the Nuclear Waste Policy Act, which established the national policy for disposing of nuclear waste by burying it. In addition, three sites, including Nevada’s Yucca Mountain, were designated as the candidate sites to be examined for suitability. In late 1987, Congress shifted its focus, requiring the U.S. Department of Energy to limit examination of repository sites to Yucca Mountain. The Department of Energy set into operation evaluation plans aimed at determining the feasibility of the use of Yucca Mountain as a nuclear-waste repository. The expected result of the endeavor is a repository that will be able to hold about 140 million pounds of nuclear waste when filled to capacity.

The scheduled completion date for the Yucca Mountain repository is 2030. The repository is expected to hold all the wastes produced by the United States by that time. It will consist of 112 miles of tunnels that will honeycomb Yucca Mountain. This maze of tunnels—to occupy more than 1,500 acres—will be approximately the length of the huge New York City subway system. The repository tunnels will be situated nearly one-half mile below ground level. Once the repository has been completely filled with nuclear wastes placed in specially designed containers, all the tunnels will be sealed. The waste containers are expected to last, intact, for two to ten centuries. After that time, as they corrode and release wastes into the repository, the geological properties of Yucca Mountain’s rock strata are expected to keep the released wastes from entering the environment for the additional ninety to ninety-eight centuries required to render them harmless.

Yucca Mountain, which is actually a six-mile ridge, has several properties cited as making it the most suitable location for the U.S. nuclear-waste repository. First, the mountain is relatively isolated, standing about one hundred miles northwest of Las Vegas and fifty miles northeast of Death Valley. Second, underneath Yucca Mountain is a layer of tough, relatively water-impervious rock, called welded volcanic tuff, that is estimated to be six thousand feet thick. Third, the repository will be seven hundred to one thousand feet above the water table in the area.

Department of Energy geologists estimate that the groundwater in the Nevada aquifer system will not be contaminated at all for more than ninety-three centuries, even though the repository is expected to leak within two to ten centuries. Contamination is expected to be avoided because of the positioning of the repository inside the mountain and the very slow penetration of any rainwater entering from the surface through the volcanic tuff to the level of the water table. Moreover, the area surrounding Yucca Mountain is very arid, receiving only about six inches of rainfall each year. Finally, the weather around the mountain is so hot that more than 99 percent of all the rainfall received is expected to evaporate rapidly, so very little water will have a probability of entering the aquifer. The hot, very dry climate around Yucca Mountain is also expected to extend the length of time it will take for the nuclear-waste containers to corrode.

Significance

The plan for the Yucca Mountain repository has had a huge impact on Nevada, the nation, and public perception of the Department of Energy and other government agencies involved in the project. A number of relevant issues are associated with the requirement by the Environmental Protection Agency (EPA) that all the stored nuclear waste must be isolated from the environment for one hundred centuries. The EPA requirement is based on the need for time to convert the dangerous radionuclides into relatively harmless nonradioactive elements through a process called radioactive decay. Many factors complicate the storage of any material for such a tremendous time period—equivalent to a process begun in 8000 b.c.e. and completed in 2000 c.e.

One factor is the possibility of future flooding of the currently arid region around Yucca Mountain as a result of climate change or earthquakes. Climate changes tremendously over a period of one hundred centuries. Most of the scientists associated with the Yucca Mountain project have stated that, based on the stability they envision from the long-standing geologic features of the area, flooding should not occur. They also point out that many studies have been or will be carried out to ensure the validity of their predictions, and that the safety of the project will be ensured before final commitment to the site for the repository.

Critical examination of the geology of the past as evidenced by the rock strata of the area is ongoing. In addition, a study of the way in which water percolates downward through the mountain’s volcanic tuff is being carried out to pinpoint the potential extent of future aquifer contamination. Much exploration is being undertaken to discover how to maximize interactions among the minerals in the tuff and any escaping radionuclides. Researchers want to determine how to immobilize escaping radionuclides and thus slow their movement downward toward the water table. Research is also in progress regarding how to design waste storage canisters so that they will react only minimally with the environment in Yucca Mountain and last as long as possible. Scientists and engineers will also examine the effects of horizontal and vertical positioning of storage containers on the rate of their corrosion.

Because Yucca Mountain is situated in an area that has had a number of earthquakes in recent times, the possible consequences of such natural phenomena are under careful examination. The evidence uncovered has led to the prediction by project geologists that only surface installations have the potential to suffer from earthquake damage. Because the transfer of wastes into the repository will take between thirty and one hundred years, the surface installations at the mountain will be constructed to be as invulnerable to earthquakes as is technologically possible.

Fears of a disaster at Yucca Mountain have derived largely from a 1987 report prepared by U.S. Department of Energy geologist Jerry Szymanski, who concluded that nearby earthquakes could suddenly drive groundwater upward hundreds of feet and into the repository during the next ten thousand years, releasing a huge amount of nuclear waste into the Nevada environment. Szymanski based his argument on the discovery of mineral deposits that indicate periodic upswellings of water through Yucca Mountain. He asserted that these periods of upswelling, which may be between ten thousand and thirty thousand years in length, make the repository site potentially dangerous. Several scientific panels have deliberated over the data and have judged Szymanski’s conclusions to be flawed. Uncertainty abounds, however—particularly in Nevada—as to the validity of the rebuttal to Szymanski’s arguments. Doubts stem from the difficulty of making extremely long-range scientific projections.

Nevadans are also anxious about the fact that errors and evidence of mismanagement have been identified at several other U.S. nuclear facilities associated with the Department of Energy. An example of this mismanagement is a planned storage facility near Carlsbad, New Mexico, which was found to leak even before its proposed opening. The project, which had been declared to be scientifically safe, stalled.

According to former governor of Nevada and U.S. senator Richard Bryan, most Nevadans believe that the other forty-nine states allied themselves against Nevada to create a dangerous plan with the potential to damage Nevada, the possessions of Nevadans, and tourism in Nevada. Polls of non-Nevadans have indicated that, in the presence of a Yucca Mountain repository, non-Nevadans would be much less likely to visit the state or to move there to live after retirement. Native American Nevadans have argued that building the repository and placing poisonous wastes inside the mountain will be a desecration of the earth.

Numerous Nevadans are also concerned about weapons testing that is conducted in the area. For example, Yucca Mountain is in the flight path of practicing fighter jets and bombers from nearby Nellis Air Force Base. In addition, several geologic faults exist in the mountain’s surroundings, and some observers are concerned about the results of past and continuing nuclear bomb tests in the area, which is part of the Nevada Atomic Test Site.

Controversy over the decision to use Yucca Mountain as a nuclear repository has continued into the twenty-first century. Delays and huge expenses have hampered efforts to implement plans for the site, even as pressures continue to mount to ensure safe storage of nuclear wastes.

Bibliography

Carter, Luther J., and Thomas H. Pigford. “Getting Yucca Mountain Right.” Bulletin of the Atomic Scientists 54 (March/April, 1998): 56-61. Describes the plans for the repository and emphasizes the importance of building such a facility to exacting standards.

Erikson, Kai. “Out of Sight, Out of Our Minds: Dangers of Nuclear Waste Disposal.” The New York Times Magazine, March 6, 1994, 34-41, 50, 63. Interesting, provocative article gives an overview of the site and its political implications. Also included are aspects of Native American viewpoints and problems that the repository could cause in the near and far future.

Grossman, Dan, and Seth Shulman. “Verdict at Yucca Mountain: Will America’s Waste Dump Be Safe?” Earth 41 (March, 1994): 54-63. Updates information presented by these authors in other articles about Yucca Mountain. Provides a clear overview of new developments and more on the science and politics of the repository. Includes several informative illustrations.

Kunreuther, Howard, William Desvousges, and Paul Slovic. “Nevada’s Predicament: Public Perceptions of Risk from the Proposed Nuclear Waste Repository.” Environment 30 (October, 1988): 16-20, 30-33. Provides background on the proposed repository and describes public reaction by Nevadans and others on the risks, thoughts about siting, and offered compensation for possible risks. Also discusses perceptions of probable impacts of the repository’s construction on willingness to live in Nevada as well as on tourism.

Macfarlane, Allison M., and Rodney C. Ewing, eds. Uncertainty Underground: Yucca Mountain and the Nation’s High-Level Nuclear Waste. Cambridge, Mass.: MIT Press, 2006. Collection of essays by experts covers the full range of technological and regulatory issues involved in the Yucca Mountain project and in the management of nuclear waste in general. Includes maps, bibliography, and index.

Marshall, Eliot. “The Geopolitics of Nuclear Waste.” Science 251 (February 22, 1988): 864-867. Brief but informative article gives background on Yucca Mountain and on details of Szymanski’s proposal and responses to it.

Schapiro, Fred C. “A Reporter at Large: Yucca Mountain.” The New Yorker, May 23, 1988, 61-67. Provides information on the public’s perception of the quality of the scientific findings and on the politics of the repository choice. Includes discussion of some reasons for the focus on Yucca Mountain.

U.S. Department of Energy. Office of Civilian Radioactive Waste Management. Site Characterization Plan: Yucca Mountain Site, Nevada Research and Development Area, Nevada. Washington, D.C.: Author, 1988. Provides public information on the project. Includes an introduction, a description of the planned site, an explanation of the repository, site characterization, and a glossary.