This concerns management and disposal of highly radioactive materials created during production of nuclear power. High level radioactive waste is generally material from the core of the nuclear reactor or nuclear weapon. The waste includes uranium, plutonium, and other highly radioactive elements made during fission. Most of the radioactive isotopes in high level waste emit large amounts of radiation and have extremely long half-lives (some longer than 100,000 years) creating long time periods before the waste will settle to safe levels of radioactivity. The management of high level waste in the Indian context encompasses the following three stages:
- Immobilisation of high level liquid waste into vitrified borosilicate glasses
- Engineered interim storage of the vitrified waste for passive cooling & surveillance over a period of time, qualifying it for ultimate disposal.
- Ultimate storage/disposal of the vitrified waste in a deep geological repository.
The technical issues in accomplishing this are daunting due to the extremely long periods involved in managing them.
- Immobilization of high level liquid waste into vitrified borosilicate glasses.
- Engineered interim storage of vitrified waste for passive cooling &surveillance over a period of time qualifying it for ultimate disposal.
- Ultimate storage disposal of vitrified waste a deep geological depository.
The basic requirement for geological formation to be suitable for the location of the radioactive waste disposal facility is remoteness from environment, absence of circulating ground water and ability to contain radionuclides for geologically long periods of time.