Coming around the mountain

Methods considered for disposal of high-level waste (HLW) include burial in the ocean floor, launching it into outer space, burial in polar ice caps, well injection and transmutation. These methods have all been rejected or left further unexplored because they were deemed environmentally threatening, politically infeasable, too costly or socially unacceptable. Burial 1000 feet deep inside Yucca Mountain's volcanic rock (called tuff), 100 miles northwest of Las Vegas, is the only method under serious consideration by scientists and government officials in the United States.

In 2001, the U.S. secretary of energy will decide whether to recommend Yucca Mountain to the president as a suitable, permanent repository. The date of the final decision is unknown and both presidential candidates, Vice-President Al Gore and Governor George W. Bush, are on record as being opposed to HLW going to Yucca Mountain permanently.

Wondering where else the waste could go? One journalist described the situation as a "corner with no exit."

Running out of room

Of the tremendous amounts of nuclear waste possibly going to Nevada, approximately 90 percent of this HLW originates from nuclear power plants -- responsible for producing 20 percent of the United States' energy supply. Unlike the energy produced from the burning of fossil fuels (coal, oil and natural gas), nuclear energy doesn't pollute the air with greenhouse gases -- only radioactive waste is left behind.

When enriched uranium -- the fuel that used at nuclear power plants -- can no longer produce electricity efficiently through fission, it is removed from the plant's reactors and is called spent fuel. Energy is produced more efficiently by this method than by the combustion of carbon atoms in coal. Spent fuel contains plutonium and emits radioactive isotopes (radionuclides) that are harmful to humans, with exposure leading to increased risks of cancer and genetic defects. The waste proposed for Yucca Mountain would take thousands of years to decay before it would no longer pose a threat to human health.

For several decades, HLW has been stored where it is made or at designated storage facilities. These facilities have large, underwater concrete vaults lined with stainless steel or aboveground dry storage facilities in steel and lead containers placed inside concrete vaults.

Power plants are accommodating the existing 60,000 metric tons of spent fuel at present, but may not be able to hold the total 105,000 metric tons of waste predicted by the U.S. Department of Energy (DOE) to be generated by 2035.

With more than 100 nuclear power plants in the United States, at least 2,000 metric tons of HLW is produced every year. The permanent repository at Yucca Mountain -- if approved -- would include approximately 100 miles of tunnels with the capacity to hold 70,000 metric tons of HLW.

Looking for room to hide

In 1987, the Nuclear Waste Policy Act (NWPA) of 1982 (42 United States Code USC 10101. Public Law PL 97-425; 96 Stat. 2201, as amended by P.L. 100-203 and P.L. 102-486) was amended, directing DOE to research a potential repository at Yucca Mountain. Other locations were researched and discussed but Yucca Mountain was decided upon because of its stable natural geologic conditions. DOE is responsible for the construction, management and operation of the potential repository.

Scientists hope to combine nature and engineering in an attempt to produce the safest repository possible.

Additionally, the NWPA (as amended) made the federal government responsible for accepting spent fuel from power plants beginning in 1998. The government has failed to take the spent fuel and consequently, lawsuits have been filed by electric utilities seeking billions of dollars in damages.

"If the government says no to Yucca Mountain and the lawsuits keep marching through the courts and the fuel gets stuck at all the plants, the total potential liability to the taxpayers is $61 billion. More storage will need to be built in the next few years," Rod McCullum, Nuclear Energy Institute's Senior Project Manager for used nuclear fuel management said.

For more than 10 years, DOE has been investigating the suitability of Yucca Mountain as a permanent, stable, central storage repository. Seven billion dollars have

been spent studying the mountain. The majority of Nevada residents as well as Nevada politicians hope the repository will not be recommended or approved. Ninety percent of the nuclear power plants are located in the eastern United States, while Nevada doesn't have a single nuclear power plant within its borders.

High-level radioactive waste (HLW) -- Primarily in the form of spent fuel discharged from commercial nuclear power reactors, it also includes reprocessed HLW from defense activities and reprocessed commercial HLW. This waste has very high radioactivity concentrations of hundreds of thousands of curies per gallon or foot.

Low-level radioactive waste (LLW) -- Radioactive waste resulting mainly from contamination of materials during the manufacture of nuclear weapons, at nuclear power facilities and in research This waste has low radioactivity concentrations in the range of one microcurie per gallon or foot.

"Worldwide scientific consensus concerning nuclear waste continues to be deep geologic disposal in a mined facility. The concept is that those generations (us) that benefited from nuclear power should be responsible for closing the cycle and disposing of this material -- protecting the public and the environment," Allen Benson, Project Spokesperson for the Yucca Mountain Project said.

HLW would travel to Yucca Mountain by truck or rail. DOE estimates an accident could cost $20 to $50 billion or more in damages and cleanup costs Opponents believe the risks involved transporting HLW are underestimated. The containers that the waste would be transported in are the same ones that the waste would be buried in which are currently being developed and tested.

Yucca Mountain's sister program, Waste Isolation Power Plant (WIPP) -- a salt mine made repository in New Mexico -- is the first and only approved permanent place for radioactive waste. In 1999, it started filling up with low-level waste (LLW) that came from the manufacture of nuclear weapons during the Cold War.

While HLW is being stored temporarily, the Yucca Mountain site is being studied and debated as a permanent place for HLW to stay. The same approach (using an underground repository) is under consideration by other nations also using nuclear power such as Germany and Russia.

"We believe that this is the safest, most practical way of doing this -- to bury used nuclear fuel at one site, in a place like Yucca Mountain, that is remote. The terrain, the environment and the water table all seem to indicate it is a suitable place," Mitch Singer, spokesperson for National Energy Institution, Washington, D.C. said.

Who knows best?

There is disagreement about the science of the Yucca Mountain site, such as the geology, hydrology and climate. Scientists hope to combine nature and engineering in an attempt to produce the safest repository possible.

For more than 40 years, the Yucca Mountain site, on federally owned property, was used as a nuclear weapons testing facility. It is considered to be an advantageous place to store nuclear waste because it is in a remote, very dry area and consists of tuff that might isolate HLW successfully.

Opponents claim the site is not naturally advantageous and that the engineered measures being taken are to compensate for the poor geologic conditions of the site -- including the composition of the rock, the location of the water table and the existing faults.

"Yucca Mountain is not a good site for a repository. It can't be made safe," Mr. Bob Loux, Executive Director of the Agency for Nuclear Projects in Carson City, Nev., said.

DOE is working to reveal how the site's rock, water and climate work together with engineered components as a barrier to prevent radioactive material from entering the environment. A five-mile underground, U-shaped Exploratory Studies Facility and a two mile Exploratory Cross Drift have been built at Yucca Mountain to allow scientists access to study permeability -- how air, water and other gases move through layers of rock.

DOE scientists suspect the tuff contains minerals that attract radionuclides, which would slow the movement of radionuclides through the rock. Radioactive particles that would move out of the repository would probably do so through water, and because the area receives less than six inches of rain a year, Yucca Mountain seems to be an ideal location. In any case, radioactive particles would have to move up or down 1000 feet to contaminate the air or groundwater, since the potential repository would be located1000 feet below the surface and 1000 feet above the groundwater table.

"The decision whether Yucca Mountain is suitable is a technical finding. The decision whether Yucca Mountain will be constructed as a repository is a political decision," Benson said.

Trembling fears

According to DOE, there has been no volcanic activity in the area for 75,000 years and overall, the geologic activity in the area over the last few hundreds of thousands of years has been relatively low. The rock above the repository would protect it from potential erosion, and it seems that the risk of damage to surface and underground facilities from faults is small because the amount of movement on local faults has been so minute. Additionally, the potential for earthquake damage is small because experience with quakes has shown that underground structures and tunnels can withstand ground motion greater than that of earthquakes.

Nevada's Nuclear Waste Project Office is critical about the excavation of a repository because of numerous earthquake faults that could move groundwater and radioactive materials through the site to the aquifer beneath and from there to the outside environment.

"Waste stored at power plants, in dry storage, is as safe as a repository for the next 150 years. There doesn't appear to be a tremendous urgency to get this problem solved today, and especially try to get it solved with a very poor site, which Yucca Mountain is," Mr. Loux said.

VWhat if?

If the secretary of energy recommends approval of the repository to the president, the president will decide whether to recommend the site to Congress in 2001. If the governor of legislature of Nevada submits a notice of disapproval Congress, Congress must decide whether to override the state of Nevada's objections and approve the repository with both houses voting in favor of it.

If permitted, DOE will submit a license application to the Nuclear Regulatory Commission (NRC). To obtain a license, DOE must demonstrate that a repository can be constructed, operated, monitored and eventually closed without unreasonable risk to the health and safety of workers and the public. The U.S. Environmental Protection Agency (EPA) would develop site-specific radiation protection standards for disposal that protect public health and the environment -- these would be implemented by the NRC.

If the repository is not recommended, DOE will stop studies and go to Congress for instruction on further action.

"Science tells us that Yucca Mountain is the right place to put used nuclear fuel. There is nothing that says a future civilization couldn't dig it up if they found a better way," said NEI's McCullum.


U.S. Nuclear Regulatory Commission -
Office of Civilian and Radioactive Waste Management, Yucca Mountain Project --
U.S. Environmental Protection Agency, Yucca Mountain --
Nuclear Energy Institute --
Washington Nuclear Corporation, Nuke --
Agency for Nuclear Projects Nuclear Waste Project Office --

Lisa Rademakers is assistant editor of Environmental Protection. She can be reached via e-mail at

This article originally appeared in the 12/01/2000 issue of Environmental Protection.

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