Of particular concern in nuclear waste management are two long-lived fission products, Tc-99 (half-life 220,000 years) and I-129 (half-life 15.7 million years), which dominate spent fuel radioactivity after a few thousand years. The most troublesome transuranic elements in spent fuel are Np-237 (half-life two million years) and Pu-239 (half-life 24,000 years). Nuclear waste requires sophisticated treatment and management to successfully isolate it from interacting with the biosphere. This usually necessitates treatment, followed by a long-term management strategy involving storage, disposal or transformation of the waste into a non-toxic form. Governments around the world are considering a range of waste management and disposal options, though there has been limited progress toward long-term waste management solutions.
In the second half of the 20th century, several methods of disposal of radioactive waste were investigated by nuclear nations, which are :
* "Long-term above-ground storage", not implemented.
* "Disposal in outer space" (for instance, inside the Sun), not implemented—as it would be currently too expensive.
* "Deep borehole disposal", not implemented.
* "Rock melting", not implemented.
* "Disposal at subduction zones", not implemented.
* Ocean disposal, by the USSR, the United Kingdom, Switzerland, the United States, Belgium, France, the Netherlands, Japan, Sweden, Russia, Germany, Italy and South Korea (1954–93). This is no longer permitted by international agreements.
* "Sub-seabed disposal", not implemented, not permitted by international agreements.
* "Disposal in ice sheets", rejected in Antarctic Treaty
* "Deep well injection", by USSR and USA.
* Nuclear transmutation, using lasers to cause beta decay to convert the unstable atoms to those with shorter half-lives.
In the United States, waste management policy completely broke down with the ending of work on the incomplete Yucca Mountain Repository. At present there are 70 nuclear power plant sites where spent fuel is stored. A Blue Ribbon Commission was appointed by President Obama to look into future options for this and future waste. A deep geological repository seems to be favored. 2018 Nobel Prize for Physics-winner Gérard Mourou has proposed using Chirped pulse amplification to generate high-energy and low-duration laser pulses to transmute highly radioactive material (contained in a target) to significantly reduce its half-life, from thousands of years to only a few minutes.