hallington on resilience learning by pjh
TRANSCRIPT
-
7/30/2019 Hallington on Resilience Learning by Pjh
1/17
The Application of Resilience Learning toUK Spent Fuel Management Facilities
Phil Hallington
IAEA Vienna, 19-22 March 2012
IAEA-CN-209-025
-
7/30/2019 Hallington on Resilience Learning by Pjh
2/17
Scope
Overview of Sellafield
Nuclear Safety Principles
Resilience Evaluation Process [RESEP]
Peer Review
Building the Programme
Sellafield Considerations
Conclusions
-
7/30/2019 Hallington on Resilience Learning by Pjh
3/17
Sellafield Context
7 shutdown reactors
2 Reprocessing plants
Waste Management High hazard legacy facilities
Product Storage
Supporting Infrastructure
Low temperature, low pressure processes
Very large inventory of radioactive material
Relatively low rates of change to loss of cooling
Aging facilities and infrastructure
-
7/30/2019 Hallington on Resilience Learning by Pjh
4/17
Nuclear Safety Principles
Maintaining containment
Maintaining cooling
Maintaining control of reactivity
Maintaining control of chemistry
-
7/30/2019 Hallington on Resilience Learning by Pjh
5/17
30-60-90 Day Plan
-
7/30/2019 Hallington on Resilience Learning by Pjh
6/17
Resilience Architecture
-
7/30/2019 Hallington on Resilience Learning by Pjh
7/17
Goals for RESEP
Provides a structured approach for the whole site
Allows for progression of events from single plant to
whole site Searches for cliff-edge effects
Develops timelines for critical safety functions (CSF)
Addresses infrastructure requirements on and off-site Identifies opportunities for resilience enhancement
Provides a key focus for damage control teams
-
7/30/2019 Hallington on Resilience Learning by Pjh
8/17
-
7/30/2019 Hallington on Resilience Learning by Pjh
9/17
Dynamics of Mitigation
-
7/30/2019 Hallington on Resilience Learning by Pjh
10/17
Timeline - Conceptual
Initiating
Ev
ent
Time
Current Backups
Alternative Backups
Mitigating Actions
Current Backups
Alternative BackupsCurrent Backups
Event A
Event B
Event C
72 Hrs 1 week
SevereAccident
Analysis
SevereAccidentManagement
Strategies
Safety CaseBoundary
RealCliff Edge
-
7/30/2019 Hallington on Resilience Learning by Pjh
11/17
RESEP Process Diagram
!"
!#
$
-
7/30/2019 Hallington on Resilience Learning by Pjh
12/17
RESEP Workshops
The key characteristics of a successful workshop are:
Strong representation from plant operators who know the plant
and are likely to be confronted with securely challengingsituations
Support from a knowledgeable technical team who haveprepared thoroughly
An open and questioning environment which is respectful of allcontributions
Methodical capture of all key observations.
-
7/30/2019 Hallington on Resilience Learning by Pjh
13/17
Building the Programme
PHASE 1 SITE RESILIENCE
PHASE 2 SITE RESILIENCEDEFINED SCOPE
EMERGINGSCOPERespond to
ONR InterimReport
Develop andImplement
RESEP
Process
Respond to
WANO SOER2011-2
CompleteENSREG
Stress Tests
and report
Develop WiderResilience
Architecture
Accelerateddelivery of
SAA/SAMS
ImplementRESEP
Improvements
Respond toWANO SOER
2011-3
Respond toFurther LFEfrom Japan
Respond toadditional
ONR Report(s)
ALARPconsiderationof outputs
Initiate Studiesinto identifiedproblems
Key topics for
peer review
-
7/30/2019 Hallington on Resilience Learning by Pjh
14/17
Summary of Key Programme Outcomes
A resilience architecture which will provide an appropriate level of robustness interms of responses, maintainability and capability to successfully managesignificant challenges to the business
Maximum learning is taken from events in Japan and effectively applied across
our operations (including effective communication with industry colleagues) Consequence led and risk informed analysis defining appropriate mitigating
actions and countermeasures which will arrest the progression of faultsequences
Investment in equipment and resources is justified against the severity ofconsequences that are effectively mitigated
A realistic view is taken of common cause effects and potential dominosituations that may arise
Effective engagement of plants and supporting functions is essential to thesuccess of these activities,
Wider public confidence in the Nuclear Industry and matters of safety is secured
-
7/30/2019 Hallington on Resilience Learning by Pjh
15/17
Decision Making Process
Decision making process for considerations Auditable, proven and accepted by key stakeholders
Including strong element of peer review
Focuses effort where greatest benefit can be derived
Flexible to late changes in understanding
Leads to an accepted resilience improvement index
Implementation
Actions to be delivered locally, by plants
Progress to be monitored centrally, by programme
-
7/30/2019 Hallington on Resilience Learning by Pjh
16/17
Draft Principles
Draft Principles for Site Resilience Following an incident, as far as possible, facilities should
be self-reliant for a suitable period (typically 24 hours).
They should also have the local capability to get the plantinto control and then into a quiescent state, withoutexternal support.
Similarly, Site should be self-reliant for a longer period,without external support, typically at least 7 days
Favouring simple, robust solutions providing value.
-
7/30/2019 Hallington on Resilience Learning by Pjh
17/17
Conclusions
Faced with translating reactor-based stress tests onto a complex suite ofnuclear chemical reprocessing plants, Sellafield Limited and its specialistsuppliers have developed an effective and systematic method of assessingresilience.
This method (RESEP) has focussed on the plants within the greatest potentialconsequences and has provided successful new insights into many facilities
beyond their Design Basis. The process has identified a range of considerations and actions which willmake a genuine and sustainable improvement in resilience.
To be success RESEP needs Thorough preparation
Knowledgeable inputs An open environment where questioning is welcomed
Close engagement with Regulators and industry colleagues has been importantto success
We at Sellafield are committed to sustaining this approach to enhanceresilience and wide incorporate this approach into our long-term periodic review
of safety cases (LTPR) which is a cornerstone of the licensing system.