The disposal of nuclear waste is one of the most alarming problems in the world. Nuclear waste is a spent radioactive fuel, which is produced by nuclear reactors or by research laboratories and medical treatments (Neil Chapman, Alan Hooper). The main risk of nuclear waste that its radioactivity can increase the possibility of cancer occurrence. Although nuclear waste is under protection of government, there is a possibility that it can be stolen by terrorist and transformed into nuclear weapon (Marvin Schaffer). In order to provide people maximum protection, spent nuclear fuel should be safely distracted or stored in controlled repository. Difficulties of radioactive waste disposal are that these materials have significantly long half-life of radiation which will not end after 100,000 years (Michelle Ragheb). The idea of this project is to find the best solution to the nuclear waste disposal problem. There are some methods to solve the issue of the spent radioactive fuel, which will be assessed: geological disposal and PUREX (Plutonium and Uranium by Extraction) reprocessing method. Firstly, they will be evaluated by criteria of safeness and reliability then the cost and lifespan of these methods will be considered. This paper will claim that the PUREX reprocessing disposal of nuclear waste is the most beneficial method.
The general purpose of geological disposal, which is considered as one of solutions to nuclear waste problem, is to eliminate a radioactive material from human and natural environment to a safe place where it will be protected from external influences such as destructive natural or human impacts. Additionally, the method of geological disposal is based on multi-barrier system, which consists of several protective layers: geological environment, buffer/backfill, metal overpack, metal container, solid waste-form. In this system, the spent nuclear fuel is placed in special container and then it is disposed underground, so the waste will gradually decrease its radioactivity by natural radioactive decay.
However, the other type of nuclear waste disposal is PUREX reprocessing method. This method involves separating plutonium, uranium and some residual waste from spent nuclear fuel. Next, separated plutonium and uranium will be burnt in heavy-water-moderated reactors or fast-neutron reactors for a new energy. Remaining residual waste can be vitrified (encased in glass) or stored in metal containers designed for a long-term storage.
A significant advantage of geological disposal is that the system of storing a nuclear waste provides safety and protection in a completely passive method. For example, once a container has been stored underground – it will not require further actions from people to control the facility and the waste that it contains, and, after hundred years, the container and the waste will become part of the natural environment
The second positive point of geological disposal is...