Nuclear Waste Sources in the Czech Republic

Both Czech nuclear power plants – Dukovany (four 440MW VVER reactors) and Temelín (two 1000MW VVER reactors) will produce approximately 4 thousand tonnes of spent nuclear fuel in total during their 40-year design lifetime. If the planned two new units are constructed at the Temelín NPP and a further one unit at the Dukovany NPP, the amount of nuclear waste to be disposed of will increase to 9 thousand tonnes of spent nuclear fuel and 5 thousand m³ of high-level waste which will require approximately 6 thousand disposal containers and 3 thousand concrete containers.

Spent nuclear fuel is currently safely stored in so-called interim storage facilities (such a facility has been in operation at the Dukovany NPP since 1995; the commissioning of a new interim storage facility at the Dukovany NPP is planned for 2010). Since spent nuclear fuel contains elements which are capable of releasing a considerable amount of energy, spent fuel could well provide a valuable raw material in the future. Nevertheless, even if spent fuel is re-used, it does not mean that deep repositories will not be required. The volume of waste to be disposed of will naturally be lower as will be the risk to the environment; consequently, the planned repository will be used more efficiently. In any case, a certain amount of spent nuclear fuel and other high-level waste will still need to be disposed of.

A few facts about spent nuclear fuel and high-level waste

In the Czech Republic, spent nuclear fuel after its removal from the reactor is currently stored at first at a so-called wet storage facility; subsequently it is transferred to a dry storage facility. Both facilities are located at the Dukovany NPP.

In the open nuclear fuel cycle (without reprocessing) spent nuclear fuel is the main waste material requiring long-term storage, together with small amounts of low and intermediate-level waste containing transuranic elements which do not require long-term storage in near-surface repositories.

The deep geological repository project envisages that disposal chambers will be constructed in a stable geological formation at a depth of approximately 500 metres (depending on the footwall characteristics); waste will be placed in special long-lifetime containers. The underground galleries may well have to cover an area of several km² depending on the amount of material to be disposed of and the design of the repository (e.g. single-storey or multi-level; horizontal or vertical arrangement of containers etc.). The underground disposal chambers and the waste disposed of in them, however, will not have any impact on above-ground activities.

The disposal chambers will be connected with the above-ground area by means of vertical access shafts or a spiral tunnel. The necessary technical facilities will be constructed within the repository’s above-ground premises and will comprise only a few hectares and will house electricity supply equipment, the repository’s ventilation system, workshops to provide mine facility services, administration buildings, social facilities, storerooms and an information centre. It is essential that the construction of the repository fully comply with both requirements concerning the environment at the given locality and the requirements of the local communities concerned.

The disposal containers will play a key role in the long-term safety of the repository and must comply with a number of exacting requirements, e.g. long-term impermeability, chemical and stress resistance etc.

In the reference project the total cost of repository development and construction were put at CZK 47 billion in 1999 prices. Costs relate principally to the investigation of the various candidate localities and the research of the rock environment at the finally selected site. The financing for eventual repository construction is gradually being accumulated in a special account administered by the Ministry of Finance; millions of CZK are paid into this account regularly by ČEZ, the Czech nuclear power plant operator, and by other radioactive waste producers.

Approximately CZK 13 billion was deposited in this account as at the end of 2009; a further CZK 1.4 billion is deposited each year.