Scientists
worldwide have studied various ways to dispose of spent nuclear fuel and high level radioactive waste.
The options included:
- Leaving it where it is
- Disposing of it in various ways
- Sub-seabed disposal
- Space disposal
- Ice-sheet disposal
- Remote island disposal
- Making it safer through advanced technologies
Scientists considered burying nuclear waste under the ocean floor. This option could be viable because deep within the ocean floor, the radiation from the waste would not harm people or the environment.
One of the problems associated with this option includes the difficulty of recovering the waste, if necessary, once it is emplaced deep in the ocean. Also, establishing an effective international structure to develop, regulate, and monitor a sub-seabed repository would be extremely difficult.
Beyond technical and political considerations, the United States signed the London Convention in October 1993. This international agreement, which remains in force until 2018, places prohibitions on disposing of radioactive materials at sea. After that time, the sub-seabed disposal option can be revisited at 25-year intervals.
The National Aeronautics and Space Administration (NASA) and the Department of Energy have researched several methods of disposal in space. Possibilities included launching waste containers into orbit around the sun.
Space disposal offers the attraction of permanent separation of waste from the human environment. However, the risk of an accident during launch makes this an unacceptable option.
In addition, space disposal is impractical because of the number of launches that would be required. Establishing international agreements on how such a program would be operated and regulated would also be difficult.
Scientists have considered disposing of nuclear wastes in the ice at Antarctica or Greenland. 
This would involve placing waste containers on the surface or in a shallow hole where the heat from the waste would cause them to slowly melt to the bottom of the ice sheet. Cables could be used to anchor the waste containers to limit the descent depth and to allow retrieval. Advantages to this option include the lack of population in polar regions and the stability and thickness of polar ice.
As with sub-seabed or remote island disposal, transportation of the waste would be a challenge. Another drawback to this option is the potential effect of future climate changes on the stability and size of polar ice masses. Radioactive wastes could be released into the environment if global climate changes increased polar ice melting. This option also would be extremely expensive due to the remote locations and adverse weather.
Finally, the Antarctic Treaty of 1959 prohibits disposing of radioactive waste on the Antarctic continent.
Scientists looked at burying radioactive waste beneath unpopulated remote islands. Islands that were considered potential candidates lacked valuable resources and were far from large continental landmasses.
One drawback to remote island disposal concerned the risks associated with ocean transport. The potential for opposition from other countries was an additional consideration.
Finland, however, is pursuing the option of disposing its nuclear waste in a stable rock mass underneath a near-shore island.
Reprocessing (recycycling) spent nuclear fuel involves using a chemical process to separate out plutonium and fissionable uranium from spent fuel rods. This process can reduce the volume of waste material. However, the byproduct of reprocessing is high-level waste, which still requires proper disposal.
Transmutation refers to a technology that involves reprocessing spent nuclear fuel, then changing the radioactive elements into generally shorter-lived substances. If developed, this technology could reduce the amount of time that some of the elements in spent fuel would remain radioactive.
Global Nuclear Energy Partnership
As part of President Bush's Advanced Energy Initiative,
the Global Nuclear Energy Partnership (GNEP) seeks to develop worldwide consensus on enabling expanded use of economical, carbon-free nuclear energy to meet growing electricity demand.
This will use a nuclear fuel cycle that enhances energy security, while promoting non-proliferation. It would achieve its goal by having nations with secure, advanced nuclear capabilities provide fuel services — fresh fuel and recovery of used fuel — to other nations who agree to employ nuclear energy for power generation purposes only.
The closed fuel cycle model envisioned by this partnership requires development and deployment of technologies that enable recycling and consumption of long-lived radioactive waste.
GNEP, reprocessing, or transmutation would not eliminate the need for a repository. The waste products from reprocessing would still require disposal. The advantage is a reduction in the amount of waste.
Last reviewed: 04/08
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