Nuclear Safety


Nuclear Power System

The Company operates two nuclear power plants. Nuclear power plant Dukovany consists of four 510MW units which were put into service from 1985 to 1987 and have been refurbished and enhanced later. The second nuclear power plant, Temelín, has two 1,000MW units which have started commercial operation in 2002 and 2003. The Czech parliament has enacted a Nuclear Act which defines certain obligations for the decontamination and dismantling of nuclear facilities and the disposal of radioactive waste and spent fuel . The Act requires that all nuclear parts of plant and equipment be decommissioned following the end of the plant's operating life, currently 2027 for Dukovany and  approximately 2042 for Temelín. A 2008 Dukovany and a 2009 Temelín decommissioning cost study estimate that nuclear decommissioning will cost CZK 17.3 billion and CZK 14.6 billion, respectively. The Company makes contributions to a restricted bank account in the amount of the nuclear provisions recorded under the Act.

Nuclear power plant overview
Nuclear power plant Installed capacity in MW Lauched in
Dukovany 4 x 510 1985 - 1998
Nuclear power plant under construction Installed capacity in MW Operation commenced in the year
Temelín 2 x 1055 Unit 1 - 2001
    Unit 2 - 2002/03
Contrasting the annual balance of primary raw material between NPP Dukovany and conventional power plants (of comparable power output)
  traditional power plant NPP Dukovany
input 11 280 000 t coal 1 500 000 tons of ore
output   total 43 t
ash 2 642 000 t  
CO2 13 500 000 t  
gypsum 563 000 t  

The summary information concerning nuclear safety of Czech nuclear facilities is provided in a detailed report, successfully negotiated within IAEA (

Nuclear Power Plant Dukovany Nuclear Power Plant Temelin
Nuclear power plant Dukovany Nuclear power plant Temelin


Dukovany Nuclear Power Plant

The nuclear power plant belongs to the organizational hierarchy of the CEZ, a.s., a joint-stock electric utility. The plant comprises four VVER 440 / 213 Units. The power plant major components (reactor, steam generators, turbines, and others) have been manufactured by Czech companies (Skoda Plzen, Vitkovice, Kralovopolska Brno, a. s.).

In October 2001, Nuclear Power Plant Dukovany was awarded an environment-friendly company status.

Within NPP Dukovany (EDU) area, additionally, a regional depository of nuclear waste (URAO) is situated , where all the operation radioactive waste (RW), developed throughout the entire operation period of NPP Dukovany a NPP Temelin, shall be deposited. In 1999, the depository was handed over to the state, on a basis of the Act no. 18/97.

Additionally, in the NPP Dukovany area, there is a spent fuel depository situated, having a capacity of 600 t, that was introduced into a permanent operation in March 1997. Currently, a construction project for another spent fuel depository with 1340 t capacity, to be located within the NPP Dukovany area, is under preparation. Thus, a sufficient storage capacity for all the fuel spent during 40 years of the NPP Dukovany operation shall be provided.

In the town of Moravsky Krumlov, there is Ambient Radiation Control Laboratory (LRKO), providing for an environmental monitoring related to the power plant operation. In the town of Brno, there is CEZ training centre, providing service to nuclear power plants.

Nuclear power plant environmental effects, apart from usual energy utility influence (such as traffic, noise, social consequences, cooling tower loss, municipal waste, etc.), consist of both liquid and gaseous radioactive effluents, solid radioactive waste deposits, and personnel irradiation doses. The nuclear power plant design solution limits an uncontrolled escape of radioactive substances and ionizing radiation from technology equipment into vicinity.

Nuclear Power Plant Temelin

Nuclear Power Plant Temelin shall operate two production units, each having 981 MWe power output. Following its connection to the grid, nuclear power plants shall hold a share of 50 %, approximately, in the CEZ total electricity production.

A construction project for NPP Temelin spent fuel repository shall start after a commencement of NPP Unit 2 operation.

Monitoring and evaluation of NPP Temelin (ETE) environmental impacts

NPP Temelin performs monitoring of its environmental impacts, in compliance with requirements stipulated specifically in legal standards and regulations. For such purposes, NPP Temelin employs ETE Chemistry Laboratories, as well as Ambient Radiation Control Laboratory, situated in the town of Ceske Budejovice (LRKO). Both facilities are provided with adequate technology and permissions to perform the relevant tasks.

ETE Chemistry Laboratories provide to the nuclear power plant the following:

  1. chemistry and radiochemistry analyses for particular technologies (chemistry mode control)
  2. chemistry analyses of surface water at selected cross-sections of Vltava River
  3. chemistry and radiochemistry analyses of waste water released from the power plant
  4. chemistry and radiochemistry analyses of subsoil water

Results of the analyses provide background information for a fulfillment of conditions stipulated in permits and decisions issued by relevant state administration and supervision authorities, as well as for evaluations of NPP Temelin environmental impacts.

LRKO Laboratories in Ceské Budejovice
Since 1991, already, the contents of radionuclides in particular environmental components are evaluated and the level of natural background dose rates in NPP Temelin vicinity is monitored. All the monitoring is performed by LRKO Laboratories, according to guidelines issued by the state expert institution, i.e., the National Radiation Protection Institute (SURO). The monitoring itself is performed according to a monitoring program, approved by State Office for Nuclear Safety (SUJB), and the power plant submits measurement results to the state supervision and administration authorities.

LRKO monitors the following components:

  • atmosphere - quality monitoring (aerosols, pollutants, precipitation)
  • surface water, subsoil water, potable water
  • sediments at surface water sample off-take points
  • soil
  • food - milk, fish meat
  • agriculture and forest products

Since 1980, when the NPP Temelin construction decision was adopted, a number of studies have been prepared, dealing with the construction project impacts on various environmental components. The Prague VUV T.G.M. institution is the most important provider of such studies, dealing with issues of both surface and subsoil water quality in the NPP Temelin vicinity since 1987, already, under a framework of a national project fulfillment.

In 1999, on a basis of recommendations issued by national expert and scientific centers, processed and prepared by INVEST project Brno Company, NPP Temelin announced a commitment to monitor its operation impacts on the environment, in excess to the scope of the applicable legislation.

These are, in particular, selected fields of both monitoring and evaluation of the environmental water component, the status of agriculture and forestry soil, bio-monitoring of atmospheric deposits of radionuclides, as well as a health status of population living within the reach of NPP Temelin.

All such tasks are summarized under a framework of "Monitoring & Evaluation of NPP Temelin Environmental Impacts Program", with its results available to the public at the power plant information centre.

The summary results of NPP Temelin environmental impacts monitoring and evaluation until the year 2000 represent a reference (initial, zero) status, as of prior to a commencement of NPP Temelin trial operation and shall provide a basis for a comparison with data collected in the following periods, as well as for an assessment of the actual environmental impacts of NPP Temelin.


Expert missions

For almost ten years Temelín Nuclear Power Plant has been under a strict supervision of the International Agency for Atomic Energy at UNO.

EIA Temelin

For the assessment of the environmental impact of Temelín Nuclear Power Plant see EIA Temelín.


The Skalka spent fuel repository area

The Skalka spent fuel repository areaThe Czech Republic government, in its Resolution no. 121/97, confirmed a recommendation issued by the Ministry of Environment, to give priority to additional spent fuel depository construction projects in nuclear power plant locations and as a depository backup option, to monitor opportunities for a central repository construction in Skalka location.

The Skalka spent fuel repository area / related both surface and underground structures and buildings / is situated in close vicinity of Tisnov – Zdar Nad Sazavou railroad at the Nedvedicka creek right hand bank, near to the town of Bystrice Nad Pernstejnem in the Zdar Nad Sazavou district, and reaches to cadastral districts of Vezna, Stritez, Bor, and Sejrek municipalities. Leveled at the altitude of 407.0 above the sea, it occupies an area of 1.5 ha, approximately /without the railroad relocation, an access road, and a forest track by-pass/.

The underground structure should be blazed in the northern part of the tectonically stable, slightly hydrated, Palena masiff, in the ridge of which /548 m above the sea altitude/ the repository discharge air shaft is terminated.

As a background support for the final decision concerning the location feasibility of the repository underground option, the Energopruzkum Praha company prepared for the CEZ company a detail project design documentation of a geological survey, including all the ancillary tests determining both quality and stability of this particular earth massif. In accordance with the project design documentation, 450 m adit together with 300 m survey drift were blazed, and a number of both field and laboratory tests were performed. Survey results were evaluated in detail and provided in Survey Final Report. A condition monitoring within the survey drift and its vicinity is maintained permanently.

The Skalka spent fuel repository would become a dry container underground storage facility, in horizontal underground tunnels of which metallic containers would be stored (packaging assemblies), containing spent nuclear fuel. The metallic container both shields and separates radioactive spent fuel from the environment and conveys to the ambient air /cooling medium/ the heat released within the radioactive transformations taking place in the spent fuel. Such a storage method makes possible either to deposit the spent fuel irreversibly into a permanent repository, or have it recycled in future, using new technologies.

The spent fuel storage is designed to be realized in the transport-storage type of containers. With such containers, it is not necessary to reload the spent fuel from storage containers into transport containers if required under circumstances. On the contrary, the spent fuel is ready for transportation without undue both time and technology demanding reload handling.

The design solution implemented assumes a placement of 2900 t of spent fuel, approximately. The transportation into the repository would be provided by railway, in a special railway car in containers licensed by State Nuclear Safety Office for both transport and storage.

In accordance with the Act no. 244/1992 Coll., concerning an evaluation of environmental impacts of structures and buildings, the Skalka location was subjected to such an evaluation process. The impact evaluation was based on "Environmental impact evaluation documentation - Central spent fuel repository - Skalka location“, submitted for public comments in August 1998. In regard of the final version of the documentation, respecting opinion and comments of relevant state administration authorities, concerned municipalities, public in general, civic associations and initiatives, an "assessment" was prepared in May 1999, and consequently subjected to public discussions. Although conclusions stemming from all such relevant procedures were positive, from the viewpoint of the Skalka repository site location feasibility, in December the Ministry of Environment issued a negative opinion of such an intention, on grounds of alleged redundancy of the construction project in view of previously approved capacity enlargement of the storage facility located in NPP Dukovany.

Problems inherent to such an opinion lay in a negligence of storage capacity requirements for NPP Temelin, as well as in the fact of describing the backup location as redundant. The backup location complements the safety of nuclear power plant operation and in future may not need to be realized. It may be used, however, in case storage facilities in nuclear power plant locations could not be realized, from any reasons whatsoever. The urgency of such safety provision needs must be identified and decided about by the operator (utility).

The State Nuclear Safety Office, on a basis of the CEZ company application from June 1998, supported by "Skalka Repository Foundation Safety Report“ and supplemented by the Ministry of Environment's opinion concerning a repository environmental impact evaluation from December 1999, issued, in accordance with the Decree no. 215/1997 Coll. and the Act no. 18/1997 Coll., its approval of the repository placement in the Skalka location, for spent fuel from NPPs Dukovany and Temelin.

The CEZ company submitted its proposal of the construction project location on 20 December 2000. Under the framework of spatial planning proceedings concerning the siting of the central repository construction project in the Skalka location, discussions were held on 15 February 2001, together with a field investigation. The Bystrice Nad Pernstejnem municipality office issued, on 28 March 2001, a construction siting decision, which came into legal force on 1 May 2001.

The spent nuclear fuel storage belongs to the end part of the fuel cycle. The storage fulfils the needs of a reduction in the spent fuel residual heat power to a level allowing for its consequent transformation or the final placement into a deep underground repository. This particular purpose corresponds with the requirement of the container's 60 year life-cycle, as the minimum.

An operation commencement of the deep underground repository first stage, into which the spent fuel shall be transported from a storage facility, is scheduled for the year of 2065. For detail information about the deep underground repository preparation, please visit the following internet address:

The Skalka location is the most suitable place for the underground option of the central repository of spent fuel from the Czech nuclear power plants.

Visits may be arranged with:

Mr. Jiri Doubravsky, MSc.
Energopruzkum, Praha s.r.o.
Phone: 566567501 (on Thursdays)
Home: 566566216

The visit must be arranged 3 weeks in advance. The visits are arranged for groups of between 10 persons, as the minimum, and 40 persons, as the maximum.

The Skalka spent fuel repository area The Skalka spent fuel repository area The Skalka spent fuel repository area