Types of radioactive waste
Radioactive waste is waste containing radioactive chemical elements that serve no practical purpose. It is often the by-product of a nuclear process, such as nuclear fission. The waste may also be generated during the fuel process for nuclear reactors or nuclear weapons or in medical applications such as radiotherapy or nuclear medicine.
Thus, when the waste has been characterized as radioactive and, therefore, must be managed as radioactive waste, the licensee of the facility or activity must transfer this waste to Enresa, and establish agreements determining the obligations of each party at each stage of waste management.
A significant danger is generated in the transport of the waste from the nuclear power plants to the centralized temporary storage facility. This transport can only be carried out inside large, extremely resistant metal cylinders.
Radioactive waste examples
In the course of their activities, it is common for industrial facilities dedicated to the recovery-recycling of metals – and to their steelmaking – to detect radioactive materials among the scrap coming from other fields of activity, industrial, medical and others.
There are very diverse activities and facilities, such as coal-fired thermal power plants, thermal establishments, titanium oxide pigment manufacturing industries, etc., in which naturally occurring radioactive materials are or may be handled. The radiological criteria for protection against exposure to natural radiation are included in CSN Instruction IS-33 and in Safety Guide GS-11-02, which develop what is established in this respect in Title VII of the Regulation on health protection against ionizing radiations.
By means of Royal Decree 1428/86 (subsequently modified by Royal Decree 903/87), the manufacturing of lightning rods with radioactive elements was prohibited in June 1986. The installation of new lightning rods with radioactive elements was also prohibited even if they were already manufactured.
Treatment of hospital radioactive waste
There are two key variables in classifying nuclear waste: the initial activity, i.e., the amount of radioactivity that will be released by the waste; and the half-life or half-life, i.e., how long the waste will decay for.
When an accident occurs in these plants, the disaster can be enormous. Radioactivity released in large quantities is lethal, and can also cause malformations and diseases in people living in the area, over several generations.
If the nuclear energy consumed in the world had been replaced by gas, the least polluting of the fossil fuels, it is estimated that some 2,388 million tons of CO2 would have been released into the atmosphere, the equivalent of putting 250 million cars on the road.
Meanwhile, administrations, companies and citizens continue to debate questions such as: Is it worth having more nuclear waste to considerably reduce greenhouse gas emissions? Is the future of sustainability and environmentalism in renewable energies? It is an open debate that leaders must address to ensure the sustainability of our future.
Radioactive waste management in Mexico
Low or medium activity waste has a relatively short life and does not generate heat, since most of it is waste made up of operating material (gloves, rags, containers, filters, resins, etc.). It is usually waste from hospitals, where radiological tests are performed, or from the decommissioning of nuclear power plants.
High-level waste is the most problematic because its radioactivity is above the limits defined as safe. They are solid materials or fuel used by power plants. They usually give off heat and radiation that decreases with time.
Many countries choose to store the waste in this way, allowing it to cool down and its radioactivity level to decrease progressively. This is a process with some risks but relatively safe, since the burial areas are thoroughly prepared and the transport is done in the most stable way possible.