MANAGEMENT OF RADIOACTIVE WASTE
The operation and dismantling of nuclear facilities generates nuclear waste and spent fuel that must be safely managed.
As can be seen in the Guideline Iberdrola Generación Nuclear must not only comply with legislation, but also aim for best practice and continuous improvement. Currently all of Iberdrola's nuclear power plant interests are in Spain, but in the event that should Iberdrola Generación Nuclear expand its nuclear power interests to other countries, the relevant national and international legislation, regulations and requirements will be taken into account.
In the case of Spain, currently the only case applicable for Iberdrola Generación Nuclear nuclear business relating waste management, the legal and national management framework is the following:
The Nuclear Energy Act, defined in article 2, paragraph 9, defines radioactive as:
“Any material or waste product, for which no further use is intended, that contains or is contaminated with radionuclides in concentrations or activity levels higher than those established by the Ministry of Industry and Energy and the previous Nuclear Security Council Report”.
The Safety Series Nº 11-G-1.1 of the IAEA (International Atomic Energy Agency) presents the classification of nuclear waste in the following classes:
- Low activity: Waste containing low levels of radionuclides that do not require shielding during transport and handling.
- Medium Activity: Waste with a radionuclide content that requires shielding and heat dissipation equipment during transport and handling.
- High Activity
- Highly radioactive liquids primarily containing fission products, like some actinides, that are separated during reprocessing of spent fuel or chemicals (aqueous waste from the first cycle solvent extraction and accompanying waste streams).
- Any other waste with intense activity levels sufficient to produce significant amounts of heat through radioactive decay.
- Spent fuel from the reactor, if declared as waste.
In this same legislation, exempted waste is defined as waste containing such small quantities of radioactive material that it is not considered radioactive and is exempt from regulatory control. The activity concentration recommended for these materials is between 0.1 Bq/g and 10E4 Bq/g.
- Council Directive 2011/70/EURATOM of 19 July 2011, establishing a Community framework for the responsible and safe management of spent fuel and radioactive waste.
Other Guides from the IAEA, such as the Safety Standard 111-S-1, also outline the criteria to be considered for radioactive waste management according to classification.
The objective of all phases of the management of radioactive waste and spent fuel is to have effective measures to protect workers, the public and the environment from the potential risks and harmful effects of ionizing radiation, now and in the future, as stated in the Joint Convention on the Safety Fuel Management and on Radioactive Waste Management, which was signed in Vienna on September 5, 1997, and ratified by Spain and published in the Boletín Oficial del Estado on April 23, 2001.
The Nuclear Energy Act states that nuclear facilities must have special facilities for the storage, transport and handling of radioactive waste. To enable compliance with the legal requirement for facility operators , Real Decreto 1522/1984, later repealed by Real Decreto 1349/2003, in 1984 created the Empresa Nacional de Residuos Radiactivos (National Radioactive Waste Company), ENRESA, as an authorized company for, among other functions:
- Treating and conditioning radioactive waste.
- Establishing systems to collect, transfer, and transport radioactive waste. It should be stressed that once ENRESA is responsible for waste and spent fuel it acquires ownership through formal transfer.
- Adopting safety measures for the transport of radioactive waste, in accordance with the provisions of specific regulations for the transport of hazardous materials determined by the authorities and competent governing bodies.
- Managing the transactions involving the dismantling and decommissioning of nuclear and radioactive facilities.
- Developing systems that ensure the safe management of their long term storage facilities for radioactive waste.
- Managing the fund for financing the activities of the General Plan for Radioactive Wastes in accordance with the provisions of Real Decreto 1349/2003.
In 1989 the Ministry of Industry established a Contrato-Tipo (Standard Contract), which is a permit granted by the state administration. This Contrato-Tipo (Standard Contract) specifies the radioactive waste management services provided by ENRESA to the nuclear and radioactive facility operators and establishes the duration and the financial compensation received for services rendered to the power plants. This Contrato-Tipo (Standard Contract) applies for the entire duration of the life of the facility, including the decommissioning of nuclear power plants.
Radioactive Waste and Spent Fuel
The General Plan for Radioactive Waste (GPRW) applies to all radioactive waste and is the primary reference document for the strategies and actions to be carried out in Spain in various fields of radioactive waste management and decommissioning, along with the relevant economic and financial study. It also presents the main data related to the generation of radioactive waste, disposal programs, facility capacity, costs and revenues, etc., so that, overall, it has its own identity to be configured as a compendium of planning in this area in Spain. It is approved by the Consejo de Ministros (Council of Ministers) and is reviewed and updated periodically. Since the creation of ENRESA, there have been six revisions of the General Plan for Radioactive Waste, which have marked the main priorities and objectives of integrated waste management system of Iberdrola Generación Nuclear, as owner and operator of nuclear plants that have been incorporated, developed and implemented.
The Consejo de Seguridad Nuclear (Council of Nuclear Security), the responsible body in Spain for Nuclear Safety and Radiation Protection Plans, approves Waste Management of Nuclear Power Plants and conducts periodic inspections to verify compliance. Additionally, the International Atomic Energy Agency (IAEA), as the international body responsible for fulfilling the No Proliferation Treaty, controls the inventory of spent fuel stored in pools at power plants.
The General Plan for Radioactive Waste is published with the aim of improving the management of waste generated at each facility. In particular, Iberdrola Generación Nuclear maintains the inventory of waste, minimizes its generation, recycles and recovers waste to the extent that it is technically and economically feasible, and prepares the waste materials (final waste) for management. The General Radioactive Waste Plan also serves to ensure that no radioactive waste is managed by conventional means and to forecast all types of radioactive waste that can be generated, including that from dismantling.
The General Radioactive Waste Plan considers the risks, both radiological and otherwise, that are associated with radioactive waste, to define global solutions. The General Radioactive Waste Plan at Iberdrola Generación Nuclear serves as a:
- Tool for the improvement and progress for waste management.
- Tool for internal communication and, where appropriate, external management of radioactive waste.
- Commitment to proper management of radioactive waste, according to general rules for the operation of its facilities.
The General Radioactive Waste Plan establishes the management lines for all types of solid radioactive waste and spent fuel and associated temporary storage, so that:
- Radioactive waste generated as a result of the operation of Iberdrola Generación Nuclear Power Plants is managed according to the methodologies adopted by ENRESA and reflected in the specific procedures for each plant
- Currently, Iberdrola Generación Nuclear's nuclear power plants store spent fuel assemblies in the pools of each plant and additionally, in some power plants, in dry storage containers, arranged in their respective Individual Temporary Storage (ITS) in accordance with the provisions of the current 6th General Radioactive Waste Plan.
- The systems of waste treatment in Iberdrola Generación Nuclear´s power plants are designed to process liquids and gases that are potentially radioactive and minimize their emission.
To obtain the authorization of exploitation, Iberdrola Generación Nuclear´s nuclear power plants must submit to authorities aWaste Management Plan for each facility, which states the criteria and methods that ensure that waste management is safe, traceable, and takes into account:
- The situation in the facility, in terms of generation, treatment and waste management.
- The identification of the origin of the waste.
- The alternative system and management processes and their improvements.
- Proof of the adequacy of management is shown and the possibility for improvements.
- The planning for implementation of identified improvements.
As indicated above, Iberdrola Generación Nuclear applies the general principle for reduction, reutilization, separation, recycling and recovery in radioactive waste management. Reduction is based on the contained use of raw materials and the restriction of materials and products entering the radiological controlled area to avoid possible radioactive contamination. Further application of this principle includes significant reductions in generation achieved through:
- Good control of technical processes where waste is generated (i.e. minimizing leaks, monitoring filters efficiency, etc.).
- Modifying and improving those processes (i.e. upgrading demineralizers efficiency, increasing compacting capacity, etc.).
- Introducing innovative new processes (i.e. in-drum drying system, reanalyzing scale factors for clearance levels, etc.).
Iberdrola Generación Nuclear applies the principle of reutilization by encouraging additional use of materials which have been found clean and without risk to personnel and pollution control (reuse of personnel working clothing prior to washing, personal toolsâ€¦). The principles of separation and recycling try to manage all of the waste including that which is radioactive, following the criteria for minimization at the source (for which infrastructure has been implemented to separate the waste at collection points where products are collected separately and, where necessary, adopting human resources that perform specific tasks of direct measurement of radioactive waste, to select and separate those without contamination). The promotion of reutilization, as well as separation, and recycling is done in the training sessions taught by staff in aspects of environmental and radiation protection. In regard to recovery, Iberdrola Generación Nuclear processes with authorized managers all collected sub products (paper, cardboard, scrap metal, plastic,â€¦) with the aim of giving value to these materials as a solution before considering them waste.
In addition to always prioritizing the minimization of waste generation, Iberdrola Generación Nuclear works with competent bodies to obtain authorizations clearance of radioactive waste from regulatory control, such as waste oil or sludge of very low activity, melting of big and heavy slightly contaminated components, etc. In these cases, management at Iberdrola Generación Nuclear is based on reducing the generation of radioactive waste by following the corresponding conditional authorization allowing the same treatment as conventional waste.
Extensive Research and Development and Innovation is either promoted or supported by Iberdrola Generación Nuclear in this area in coordination with ENRESA, R&D bodies and national authorities.
Safety assessments of different kinds and frequencies are carried out during the whole life of the projects. Specifically during the operation phase the following amongst others can be mentioned: annual quality assurance audits, biennial company safety review board audits, decennial comprehensive periodic safety review. All of these are performed by the licensee, in addition to the frequent audits performed by the regulatory authority.
Management procedures and approaches consider the impact on decommissioning wastes in all phases and at all times during the operational life of the plant. No unpredicted amount of decommissioning waste should be expected at the end of the operational lifetime.
During the operating life of the plant two kinds of radioactive waste may be generated:
- Operational waste, which results from the normal energy generation process, which are treated, conditioned, stored temporarily on site (fuel) or shipped away on a routine basis.
- Structural or decommissioning waste, which are comprised of the facility itself and any specific heavy component which might have to be replaced before decommissioning (i.e. steam generators).
Iberdrola Generación Nuclear is paying fully for the provisions needed for decommissioning to the national fund managed by ENRESA according to the nuclear energy generated by their plants and following the stipulations of the General Plan for Radioactive Waste.