1. New Nuclear Build - Economic Regulation? Gregg Butler Director: Integrated Decision Management Ltd Professor of Science in Sustainable Development, University of Manchester

2. Reactors in the UK – Experience to date Generation I Magnox: 10 stations – 9 different designs (plus another two exported!) Generation 2a AGR: 7 stations – 4 designs, 3 design and construction consortia Generation 2b PWR: 1 station, derived from US design but extensively modified – ends as very much a one of a kind Comment: 18 reactors, 14 designs only the near-identical Heysham 2 and Torness stations were built in parallel, and this proved very beneficial in minimising delays and improving construction efficiency

3. Licensing Regime Safety licensing regime therefore developed to cope with anything Permissioning regime based on Safety Assessment Principles (SAPs) Risk levels governed by Tolerability of Risk Safety improvement driven by So Far As is Reasonably Practicable (SFAIRP) within the framework of Tolerability of Risk

4. Tolerability of Risk Effect on maximally exposed individual - Tolerability of Risk 10 -6 10 -4 10 -2 10 -8 Unacceptable region Risk cannot be justified save In extraordinary circumstances Broadly acceptable region ALARP or Tolerability region Tolerable only if risk reduction is impracticable or if its cost is grossly disproportionate to the improvement gained Tolerable if cost of reduction would exceed the improvement gained Workforce Public Necessary to maintain assurance that risk remains at this level

5. ToR – Gross Disproportionality – Where to Stop? If Gross Disproportionality is to be bounded then the Tolerable and Broadly Acceptable regions need to be stabilised All the current signs point to erosion –Nuclear site delicensing now relies on meeting 10 -6 as a limit –In the environmental field, guidance on BPM explicitly removes any thought of valuing Gross Disproportionality

6. ToR – Gross Disproportionality – Where to Stop? A Review of the Application of Best Practicable Means within a Regulatory Framework for Managing Radioactive Wastes - March 2005 : As a matter of principle, the (Environment) Agencies define no lower threshold of dose or environmental contamination below which BPM does not apply ……Put simply, BPM requires site operators to ensure that the measures in place to manage radioactive wastes are not unreasonably costly. In all cases, however, the onus is on the site operator to implement measures to the point where the costs of any further measures would be grossly disproportionate to the risks they would reduce or avert. …….a quantitative definition of grossly disproportionate would be difficult, if not impossible

7. Licensing Regime and PWRs The UK licensing regime has only had one try at licensing an international design Sizewell B was an operating US design, and was examined from the ground up Time pressures were not on the project teams side – they gave in a lot! Sizewell ended up much more complex and expensive than its mother station – with many developments during the late stages of design and even during the build

8. Licensing and Regulation – Sizewell B Took 14 Years to Plan and Build From www.niauk.org Sizewell B experience - 7 years from site selection to site license - Construction 6.5 years

9. Any risk of a repetition = no chance for new build! From www.niauk.org Sizewell B experience - 7 years from site selection to site license - Construction 6.5 years