Nuclear fuels should be manufactured, stored, used, recycled, and disposed under international supervision. The greatest economic benefits should be obtained from used nuclear fuels or nuclear wastes before they are permanently disposed. This would include the extraction and recycling of virtually all marketable radionuclides from nuclear wastes.
High level nuclear wastes which are not marketable should be required to be handled in two ways.
- First, wastes with half-lives longer than 100 years should be required to be transmuted, if practical, to isotopes with half-lives shorter than 100 years. Then these transmuted isotopes, as well as other radionuclide wastes with similar half-lives, would be stored at secured locations in such a way that would always allow inspection and maintenance personnel direct access to the waste storage containers. These waste containers would be held in this kind of storage for an amount of time necessary for the longest half-lived radionuclide which is stored in the container to go through four half-lives. Under these guidelines, 400 years would be the maximum amount of time nuclear wastes would spend in this kind of storage. After this amount of time has elapse, the nuclear waste would be only 6.25% as radioactive as the original waste. The waste can continue to be protected and monitored, if desired, but without needing such high levels of security.
- Second, radionuclides having half-lives longer than 100 years, and which cannot be practically transmuted to shorter lived isotopes, should be required to be disposed in a way that would not necessitate the provision of long term security against accidental or intentional human or environmental harm. Namely, these wastes should be taken off the planet and disposed in a way that would make human retrieval or sabotage impossible. These nuclear wastes should be launched into space in small packages using rail guns, laser launch systems or other similar ground-based launching technologies. These packages containing waste should be launched with enough energy and with properly equipped launch vehicles to place it immediately (without orbiting the earth) into a trajectory that, within a few years, would either intercept with the sun or would take the nuclear waste permanently out of the solar system. There should be no intentional fly-by the earth or gravity assists using the earth. If the nuclear waste could be rapidly crashed straight into the sun to achieve the deepest possible penetration, the intense solar energy would vaporize the waste and should effectively dilute it to the point that even if it were to escape from the sun via the solar wind, the pollution would probably not be scientifically detectable. Another possibility would be to crash these vehicles on one of the gas planets just so we receive confirmation that the wastes have been permanently disposed and are not continuing to wander somewhere. However, though these wastes would become incredibly diluted within these planets, this practice may potentially significantly contaminate these planets, interfering with and affecting the accuracy of future scientific investigations.
If the cost of launching small quantities of waste using ground-based launching systems are low enough and if the reliability of such systems are high enough, it may be both safer and more economical to dispose of more radioactive wastes in this manner rather than holding them under high security storage over multiple half-lives on this planet. For example, we could use the space disposal method to dispose of radionuclides with half-lives of 75 years, 50 years, 40 years or even less, depending on cost. Radionuclides with half-lives of less than 20 years do not present overwhelming Earth-based storage problems because they would decay to relatively safe levels within an average human lifespan.