Nuclear waste storage is an issue of interest in many regions of the world, thanks to the widespread use of nuclear technology in energy generation, medicine, and warfare. It has also been a topic of controversy, as governments struggle with nuclear waste and what to do with it. There are a number of options for storing nuclear waste which are designed to address the safety issues involved with nuclear material.
The issue with nuclear waste is that it has been deemed useless, but it is still dangerous. Nuclear waste can continue to emit radiation for centuries, and it could potentially become unstable if handled and stored improperly, setting off a chain reaction which could create a nuclear accident. If it fell into the wrong hands, it could be used to make a dirty bomb which would spread radiation over an inhabited area. Nuclear waste storage focuses on finding safe and secure ways to store spent nuclear fuel and other forms of nuclear waste until they stabilize enough that they do not pose a threat to humans, wildlife, and the environment.
Temporary nuclear waste storage is typically the first step. In many cases, nuclear waste is extremely hot when it is generated, and it needs some time to cool down. At locations like nuclear power plants, spent nuclear material is submerged in pools filled with boric acid to allow it to cool and stabilize. These pools are usually made from steel-lined concrete to prevent leakage, and they are definitely a temporary measure.
Once nuclear waste is cooled, it can be moved into dry cask storage. Dry cask nuclear waste storage involves extremely durable barrels which are designed to prevent leaks of radiation. The casks can be filled with waste and stored above ground safely, although they are also designed ultimately for temporary storage. Over the thousands of years which may be required for the waste to stabilize, the casks could fail or be breached.
For long term nuclear waste storage, it is necessary to find a safe place to keep the material while it breaks down. Burial is one method which has been widely promoted, as the nuclear waste can safely break down underground or under the ocean floor in remote areas. The issue with burial is that the nuclear waste could leak or be breached by earthquakes or human activity. There are also concerns about the fact that in several thousand years, it is unlikely that knowledge of the site as a dangerous location will survive, which means that future civilizations could unwittingly release toxic materials into the environment when they breach storage facilities.
Some nuclear waste management specialists have suggested that waste could be shot into space, but this could also cause problems in the future. While space is currently a hostile environment for humans, this doesn't necessarily make it a great place to use as a dump, not least because if other life forms do exist, they will probably not appreciate floating barrels of nuclear waste drifting through the universe.