It is not only the use of fossil fuels that pollutes our surrounding but even the use of nuclear energy gives rise to pollutants and hence pollutes our environment. Also the pollution caused by the use of nuclear energy from fission process is much more damaging than pollution caused by burning fossil fuels.
The fuels like U- 235 are radioactive substances which keep on emitting some nuclear radiations all the time. The dangerous nuclear radiations can enter into the environment- by leakage from nuclear reactors where fission of U-235 is going on. These nuclear radiations can cause damage to cells and in some cases even lead to death.
The waste materials produced during the various steps of the nuclear energy production are collectively known as nuclear wastes. If these radioactive wastes are dumped in garbage bins, they will emit nuclear radiations and pose a threat to the life of men and animals. If they are dumped in rivers or sea, they will contaminate water and damage aquatic life.
This has become an issue of legitimate concern to the public after the Chernobyl accident of Russia. More 99% of the total radioactivity in the entire nuclear fuel cycle is generated from the fuel processing plants. To ensure that this highly radioactive waste does not pose any hazards to the environment. For this purpose, a three stage approach has been adopted.
First the waste will be incorporated in stable and inert solid matrices. The conditioned waste will then be placed in canisters and kept in a retrieval store under cooling and constant surveillance. Ultimately, the canisters stored in suitable place. A waste immobilization plant for incorporating the high level radioactive wastes generated from the fuel processing plants is being set up along with the solid storage surveillance facility of Tarapur.
Immobilization involves verification of radioactive waste which is coded at underground disposal. The canisters in storage are air cooked by natural convection and when the heat radioactivity decay to desired level, they are transported to a suitable geological formation for ultimate storage. A graveyard for storage of nuclear wastes has been established in Trombay for nuclear waste disposal.