The was designed to limit the spread of Nuclear Weapons.
Can thorium reactors dispose of weapons-grade plutonium?
September 05, 2017 — — The Trump administration is committed to finding a long–term disposal solution for the nation's nuclear waste, but Congress first needs to fund the effort, a top Department of Energy official said Tuesday in Las Vegas.
U.S. GAO - Key Issues: Disposal of High-Level Nuclear Waste
The approximate half-lives of some of the isotopes in the spent nuclear fuel are listed below:It is clear from the table above that the left over nuclear isotopes from the generation of electricity through nuclear power are extremely long lived and therefore must be shielded from humans and the environment for a long time.
Soviet atomic bomb project - Wikipedia
Eventual final disposal of nuclear waste means that the radioactive isotopes will be buried (with appropriate barriers - see "Final disposal" above) in an appropriate disposal site for a very long time.
Nuclear Power Education - The Challenges of Nuclear Power
For example the International Atomic Energy Agency runs frequent conferences on the science of nuclear waste disposal, setting and enforcing safety standards, monitoring safety and security of nuclear waste.