At 98 pages its seems a bit bloated. Maybe the authors get paid by the page and haven’t heard the famous quote “I am sorry to have wearied you with so long a letter but I did not have time to write you a short one” .
I think that this is an informative graphic. It comes from a presentation about risk based ALARP (As Low As Reasonable Foreseeable) by David Forsythe, Head of Nuclear Safety, Decommissioning from Sellafield at the 2016 SRP Conference.
He discussed the dilemma posed by legacy facilities that are below modern standards of safety, where several facilities are interdependent and for which decommissioning poses additional risks. Do you “keep the plane on the ground” where you believe risks are lower or do you decommission? (You can gain some impression of the difficulties posed by the Sellafield site from this NDA Document.)
The blue line in the diagram above (taking from the presentation with permission) shows the development of risk with respect to time for a well designed decommissioning project. It accepts that risk may rise as the work gets underway but will then drop below the initial value as the work progresses. The art is to minimise the area under the curve and steer clear of yellow, orange or red regions. Prevarication will lead to risks not being reduced and probably increasing with time as the systems degrade. This leads to, at best, an unacceptable time at risk (Region C) or, at worst, an eventual failure of the system or reaching a position from which the overall programme cannot be delivered (Region E).
David explained that the processes that manage delivery and the processes that manage the upper safety boundary need to balance to deliver ALARP and secondly that the ALARP “landing plan” dictates what “safe enough” looks like for the components of the plan.
There is an article by Steve Kidd on the Nuclear Engineering International website (here) that complains that the global warning issue has been pushed as a reason to support nuclear power with absolutely no success.
Kidd contends that “The problem is that nobody has ever built a nuclear power station to curb carbon emissions. The industry’s PR effort has got seduced by the environmental case, but this has been a major mistake. This is perhaps an understandable one given the prominence of the debate about climate change, but it has become a fatal distraction.”
Nuclear power plants, he claims, were all built to provide cheap and reliable power with environmental gains being secondary.
Unfortunately he then goes on to say that we can solve the problem by ditching the linear no threshold hypothesis (LNH) to remove the public fears about radiation. Just is just daft. The LNH is supported by the ICRP, not necessarily because it is believed but because it is “the best practical approach to managing risk from radiation exposure and commensurate with the precautionary principle” (ICRP 103-36). I can’t see the public’s long engrained radiation dread (Paul Slovic) disappearing overnight if ICRP change their policy and I can’t see any reason why ICRP would change its policy.
The NDA have published a progress report on their Priority Programmes and Major Projects. This makes interesting reading and shows how complex the Sellafield site is and how careful the work to decommission the site has to be planned. Some very long programmes – going out to 2052.
The Berkeley Vaults clearance does not seem to be going well. In 2011 it was expected to cost £212 Million and finish by 2015. It is now budgeted at £297 Million and programmed to finish in 2020. However the note suggests that with a new PBO in control and a “consolidation process” being undertaken all bets are off.
The GTA was introduced following the Three Mile Island accident in 1979 after which the Government reviewed UK civil nuclear emergency response arrangements. That review identified a need for somebody to provide authoritative and independent statements to the press and broadcast media in the event of a civil nuclear emergency, and to advise the emergency services on actions to protect the public. The review also concluded that the most suitably qualified person to undertake the role would be a senior member of HM Nuclear Installations Inspectorate (NII). As a result, the arrangements for appointing a Government Technical Adviser were put into effect. (Ref. NEPLG Guidance)
Now, as a result of greater use of COBR and SAGE as described in CONOPS, the GTA is considered unnecessary. I’m not sure that I agree that the two mechanisms cover the same service.