Behind climate change, radioactive disposal can arguably be one of the largest issues that future generations will face. Like all processes, nuclear energy produces waste. However, nuclear waste contains radioactive elements that are incredibly dangerous to both the environment and humans. As such, as soon as a country decides to use nuclear technologies, they need to be prepared to dispose of the waste properly. In order to achieve this, people and the environment must be protected by the hazards presented by nuclear waste now and in the future.
Nuclear waste is classified depending on the half-lives and the level of radioactivity of the nuclides in contains. Techniques exist to manage this radioactive waste and the spent nuclear fuel from plants and research reactors in a safe and secure way. Waste containing only radionuclides with very short half-lives can be stored for days or years to allow for the decay of the nuclides. This type of waste is usually generated when radioactive materials are used for research or medical purposes.  Eventually it can be disposed of as conventional waste.
By volume, most radioactive waste has low levels of radioactivity. This includes the majority of waste that comes from routine activities at nuclear power plants and waste that is produced when radioactive medical or industrial devices are no longer needed. Devices could possibly no longer be needed because the source has decayed and the remaining radioactivity is not strong enough for its original purpose. In these cases, the radioactive source needs to be removed from the equipment and prepared for storage and eventual disposal. Many countries process their waste at centralized waste management and storage facilities. Such processes can involve measures to reduce the volume of the waste such as compaction, incineration, or capsulation to immobilize the contaminant. After being placed in appropriate containers, the waste is stored until a suitable place or system for its disposal is established. 
Alongside the radioactive waste produced by the routine activities at a nuclear power plants and from low- level devices, nuclear power plant generation produces spent fuel, or high level waste. This waste is low in volume but has a high level of radioactivity, remaining hazardous for thousands of years. In some countries, the spent fuel that is no longer of use in its current state is reprocessed to extract usable material for new fuel.  Other countries consider the spent fuel as waste for direct disposal. In all countries generating nuclear power the spent fuel is currently stored in either water pools (up to 10 years) or dry casks at secure storage facilities until a preferred method of longtime disposal is decided. 
Waste management experts around the world agree that geological disposal facilities (GDF) are the best and preferred option as a solution for intermediate and high level waste and spent nuclear fuel. This would be in a location where geological conditions are stable and the waste can be contained and isolated from humans and the environment until it no longer presents a hazard. Currently, GDF's are in development in Finland, France, Switzerland, and Sweden. In a GDF, multiple barriers help to ensure that radioactive material isn't released into the environment. 
Geological disposal facilities are currently the preferred option for nuclear waste management in many countries, including Canada, USA, Finland, Republic of Korea, the UK, and Australia. In these countries, GDF developers must demonstrate to regulators and the public that there will be no impact on humans, animals, or the environment should these barriers fail at any. As of now, there is scientific consensus that an appropriately sited GDF provides more than enough level of protection for our planet.
© Jack Barber. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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