KRB-A (Grundremmingen, Germany)

1. KRB-A (Grundremmingen, Germany)

2. KRB-A General Description • Type:Boiling Water Reactor • Power: 250 MW(e) • Started in 1966, shut down in 1977 • First commercial power reactor in the Federal Republic of Germany

3. KRB-A Layout

4. KRB-A Project Summary • 1977: reactor shut down • 1980: decommissioning planning • 1983: phase I: removal of components and systems in the turbine house • 1990: phase II: decommissioning of primary circuit • 1992-date: phase III: dismantling of RPV, internals and biological shield • 2005: complete reactor removal

5. KRB-A Operational lessons learned • The use of chemical decontamination to minimise waste for disposal • Ice sawing technique successfully used to stabilise and cut through tube bundles • Thermal cutting is flexible and reliable • Mechanical tools are simple to handle

6. KRB-A General learning points • No single dismantling tool • Avoidance of complicated techniques • Clearly defined waste management process

7. KGR (Greifswald,Germany)

8. KGR General Description • Type:8 Pressurised Water Reactors • Power: 440MW(e) each • Four reactors operational between 1973 and 1990 • Reactor units based on Russian WWER design, three reactors never commissioned, one test operation

9. KGR Project Summary • 1989-90: units 1-5 shut down and construction of units 6-8 halted • 1995-2009: dismantling of equipment, units 1-5 • 1998: start of Interim Storage North (ISN) operations • 1999-2002: demonstration remote dismantling, unit 5 • 2004-2007: dismantling of reactor and internals, units 1-4 • 2012: completion of reactor buildings demolition

10. KGR Site re-use Harbour construction works at the former cooling water outlet channel

11. Removal of large components to the ISN for decay storage RPV (214Mg) Steam generator (166Mg) KGR Progress Percent dismantling complete (by mass) as at May 2004 Unit 1 71% Unit 2 73% Unit 3 16% Unit 4 66% Unit 5 80% Turbine hall 51%

12. Total mass site decommissioning waste 1,800,000 Mg Radiologically unrestricted material 1,233,600 Mg Other radioactive residuals 566,400 Mg Remaining building structures 471,200 Mg Concrete for radioactive waste or decay storage 26,000 Mg Dismantling plant parts 69,200 Mg Sorting, packaging and buffer storage Unrestricted release 511,100 Mg Restricted re-use 2,500 Mg Conventional waste 3,750 Mg Decay storage 28,400 Mg Controlled re-use in nuclear facilities 4,150 Mg Radioactive waste 16,500 Mg KGR Waste management

13. KGR Operational lessons learned • No specific problems • Development of a comprehensive inventory • Use of simple, sturdy equipment • Complete planning - shut down to disposal • ALARA principle

14. KGR General learning points • Challenge to project management and logistics • Social aspects - strategy for site re-use • Clear and realistic requirements from the licensing authority • Open dialogue with the public

15. Refuelling machine in reactor hall Long term spent fuel store Steam generators Turbines Reactor Primary circ. Turbocompressors NPP-A1 (Jaslovske Bohunice, Slovakia)

16. NPP-A1 General Description • Type:Heavy Water Gas Cooled Reactor • Power: 143 MW(e) • Started in 1972, shut down in 1977 • Experimental and power prototype reactor for the development of gas cooled, heavy water moderated reactors using natural uranium.

17. NPP-A1 Project Summary • 1977: reactor shut down • 1980-94: transition period • 1999: all spent fuel transported to Russia • 1999-2007: first decommissioning phase • 2008-2033: final decommissioning

18. NPP-A1 Operational lessons learned • Decommissioning greatly influenced by reactor history (accidents) and fuels and liquid waste storage issues • Successful co-operation with European companies • Use of operational staff knowledge • Clear definition of waste management routes and process requirements • Carrying out activities in small steps with small teams

19. NPP-A1 General learning points • Maintaining fuel cladding integrity during operation • Co-operation between project managers, technicians, health physicists and regulators

20. Summary of lessons learned(1) Initial characterisation Impacts cost, schedule, decontamination strategy, waste managaement

21. Summary of lessons learned(2) • Tools and equipment • Simple, appropriate, tested, commercially available where possible • manual > remote • develop contingency solutions and tooling • consider effect of aging

22. Summary of lessons learned(3) • Operational management • remove debris promptly and in a controlled way • consider effect of temporary systems on existing systems • establish a fit for purpose working environment

23. Summary of lessons learned(4) • Risk management • prioritise • take a total risk approach avoid creating new hazards • consider non radiological and radiological hazards equally • risk assessment/management must be an ongoing process

24. Summary of lessons learned(5) • Waste management • plan all operations • minimise production of wastes e.g. segregate wastes at source • do not generate a waste stream until a disposal strategy has been defined • adequately consider effect of decontamination techniques on secondary waste generation, cost, worker health and safety

25. Summary of lessons learned(6) • Staff experience • make use of available expertise • maintain team continuity where possible • small experienced teams are generally more effective

26. Summary of lessons learned(7) • International collaboration • benchmarking • exchange agreements - sharing technologies and experiences

27. Summary of lessons learned(8) • Stakeholder involvement • openness and transparency • develop mechanisms for consulting and dissemination of information

28. Questions?