Radioactive waste – three main related economic task

• How to finance decommissioning

• How to finance radioactive waste (final) disposal (of different types)

• How to finance temporary storage of spent fuel

RADIOACTIVE WASTE CLASSIFICATION

• According to activity level

  • Low level waste (LLW)

  • Intermediate level waste (ILW)

  • High level waste – spent fuel

• According to half time

  • Short lived isotopes

  • Intermediate lived isotopes

  • Long lived isotopes

• According to origin

  • Industry, hospitals, research institutes, etc.

  • Nuclear power

Basically at least 10 half-times are needed

CZECH CASE EXAMPLE

(similar to other EU countries)

• Responsibility of state – long time horizons

  • State authority responsible for waste record keeping (origin, amount, processing) and for waste disposal – SURAO in Czech republic

  • Waste originator should bear all current and future cost of waste management (uncertainty in future knowledge) – regulated fee

Decommissioning

• Owners of nuclear plants should create provisions in money (bound account), periodically audited and approved by

• System for LLW and ILW waste disposal – payment for one equivalent container (drum in drum system)

  • Institutional waste – three existing repositories (Richard, Bratrstvi, Dukovany)

  • Nuclear waste

• System for spent fuel disposal – payment for 1 MWh produced

  • Deep geological repository – expected opening in 2065

NUCLEAR POWER PLANT – ACCIDENTS

Windscale – GB 8.10.1957, 5 points on scale

• Grafite reactor, military purposes

• Carelessness of reactor stuff – over heating of some fuel cells, ignition of surface from magnesium, fire took 4 days, 8% of fuel melted, app. 1.35 x10¹⁶ Bq released to the atmosphere

• Area of 520 km2, drinking of mil prohibited, dose of public near plant – 5-60 mSv

• Minimal attention of public (accident more important than in TMI)

Three Miles island, USA, 28.3.1979, 5 points on scale

• PWR reactor, 1 year old, 880 MWe

• Leakage of water from primary circuit, broken valve

• Bad understanding of situation by staff, loss of cooling water, active zone started to melt

• Threat of chemical explosion – water decomposed into oxygen and hydrogen

• One week of stabilization, serious contamination of primary circuit, some leakages (under hygienic limits) to the environment

Jaslovské Bohunice, 22.2.1977, Slovak rep., 5 points on scale

• Experimental reactor, 103 MWe, in operation from 1972

• Natural uranium, moderated by heavy water, cooled by CO₂,

• Mistake of stuff when completing new fuel cell (continuous fuel exchange, each day some fuel cells is necessary to exchange)

• Forgotten small bag with silicagel, cooling at this part of reactor blocked, warning signal switched off (false signal in past month), melting of fuel, operators tried to get back fuel cells, but impossible

• Penetration of heavy water into primary circuit, fast erosion of fuel surface

• Contamination of primary and part of secondary circuit

Černobyl nuclear power plant accident

• Biggest acciedent

• 4 block of 1000 MWe in operation, 3. and 4. block put into operation in 1983

• 2 block under construction

• RBMK reactor type – grafite reactor, boiling reactor, one circuit scheme, different organization of active zone, no pressurized vessel, 1693 channels

• Continuous fuel exchange, higher plutonium content

• Unstable on some conditions

• Complex system fro zone stabilization

Accident

• Experiment on 4 block – testing of new equipment in case of accident – power delivery

Causes of accident

• Direct – combination mistakes and breach of rules

• Indirect (system)

  • Psychological mistake of constructors

  • Pressure to fulfil planned activities

18