Page 1
Sellafield Integrated Waste
Strategy Update to Version 2
June 2008
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June 2008
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June 2008
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Executive Summary
The development and subsequent annual reporting of an Integrated Waste Strategy (IWS) for
Sellafield addresses specific requirements within the Radioactive Substances Act 1993 Authorisation
for Sellafield site, Nuclear Site Licence Condition 32, and the contractual arrangements between
Sellafield Limited and the Nuclear Decommissioning Authority (NDA).
This report provides an update in the steps which continue to progress towards a fully integrated and
optimised waste strategy. It is written as an addendum to the 2007 IWS (Version 2) report and the
reader should refer to Version 2 for further context and background.
Vision, Aims and Objectives
The Sellafield IWS is a live strategy, subject to annual review and update, which provides the
rationale behind the waste strategy aspects of the Sellafield site Lifetime Plan (LTP). It is a subset of
the Integrated Strategy for Sellafield which considers a wider range of factors such as hazard and risk
reduction, commercial goals, national policy and affordability. The Vision of the IWS for Sellafield was
described in Version 1 (June 2006) as:
An Integrated Waste Strategy will deliver an operating site that has minimised waste
generation and where waste is generated, it is contained in a manner that achieves
sustainability; where sustainability is waste in a form that requires ideally nil, but probably
minimal, management to safely protect people and environment including the remediation of
historical impacts.
To support this vision, the site aims to continually develop an IWS and pursue Waste Minimisation
and Sustainability.
The IWS achieves these aims by:
providing an overview of wastes on the Sellafield site
providing a methodology for practicable application of the Waste Management Hierarchy
(WMH)
enabling the site to envisage and develop waste routings
identifying opportunities and challenges within future waste routings
facilitating holistic management of wastes and making waste management arrangements
more transparent
informing site strategies and enabling top-down direction setting to drive the business
The rate of progress in implementing the IWS is influenced by:
a) the need to be consistent with a higher strategic driver for the site of ‘hazard and
environmental risk reduction’
b) affordability of the implementation plan in any given period
Scope
This report summarises the progress and developments since the IWS was last reported, by Version
2, in June 2007. It addresses:
• how component waste strategies have developed since June 2007
• the impact that the previous version of the IWS (Version 2) had on the plans and strategies
included in compiling the next LTP
• new drivers that have gained prominence since the IWS was last reported
As such, this report is considered to be an “update” to the previous version of the IWS rather than a
new version. This update therefore summarises the current state of implementation of the waste
management strategy covering radioactive and non-radioactive solid, aqueous and gaseous wastes
and any material which has the potential to become waste in the future.
Exclusions
In agreement with the NDA this annual update specifically excludes a full scale revision to the full
document format as prescribed by the NDA procedure ENG 01. Rather this addendum is intended to
provide a fit-for-purpose update to the current status of the IWS for Sellafield. Also excluded are
Windscale and the National Nuclear Laboratory (NNL); spent or irradiated fuel, and uranium and
plutonium, as these are not classified as wastes.
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June 2008
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Progress
The IWS has developed from being a statement of the baseline waste management strategy at
Version 1 (June 2006), to an integrated strategy for the future in Version 2 (June 2007).
Since Version 2 considerable progress has been made in translating this strategy into the LTPs for the
site. In particular:
• all wastes and routes have been identified
• estimated quantities of waste have been reassessed for both raw and conditioned volumes
• Opportunities have been identified for waste minimisation and the use of existing facilities.
These have either been incorporated into the LTP or identified for further assessment.
• Strategies for implementation are being developed for Low Level Waste (LLW), Intermediate
Level Waste (ILW) and Plutonium Contaminated Material (PCM)
• Tools and techniques to facilitate quantification and assessment and to enable the visible
management of wastes information have been developed e.g. Sankey Diagrams in Version 2
and the Overall Effluent Strategy Model (OESM).
• The analysis has contributed to the NDA-led national strategies, in particular ILW and LLW
strategies.
By following the structured process, developed in Version 2, and embedding the outputs of this into
LTP the site has made significant progress towards its goal of transforming the IWS into a functional
everyday aid for the strategy team and site management, and hence to the site for running our
business and addressing the stated aims of the IWS.
The largely ‘integrated’ position established by Version 2 (June 2007) has been successfully
strengthened in the past 12 months through the tactical deployment of the IWS principles developed
in IWS Version 2 (2007) within the component waste strategies and operating unit work plans.
Furthermore, the methodology followed gives the site confidence that, based on current assumptions,
it has successfully identified:
• its wastes inventory and arisings profiles
• their routings and any potential bottlenecks
• the potential new plants and routes required to appropriately treat and dispose of these wastes
These findings have been implemented, as appropriate, into the LTP developed for the site.
Uncertainties
There remain considerable uncertainties which pose a challenge to the development of an integrated
and optimised IWS. Specifically, current prominent uncertainties include the necessary financial
provision to deliver the current strategy, technical challenges, and the consequential impact these
uncertainties may have on the timing of other supporting strategies. These uncertainties are outside
of IWS control and future development of the IWS will be informed by the outcome of work which is
currently ongoing to better define and resolve these uncertainties. Additionally, the Department for
Environment, Food and Rural Affairs (DEFRA) review of the UK Discharge Strategy, the subject of a
period of public consultation this summer, has the potential to further impact on the site strategy.
Risks
The IWS can be potentiality impacted by a number of future risks. The current risks can be grouped
under three high-level categories:
• LLW – Risks are dominated by the uncertainty that surrounds the Low Level Waste
Repository (LLWR) regarding potential changes in waste acceptance criteria, future capacity
and the potential for disposal costs to rise.
• ILW – Many of the risks for ILW arise from the current uncertainties surrounding the deep
repository, including delays in availability, which would extend current store lifetimes, and
changes in acceptance criteria which may lead to rework or over-packing for existing
packages.
• Site Wide – These include risks associated with the major operations of the site, such as
concern about the High Activity evaporative capability, fuel reprocessing throughput and
available funding adversely affecting execution of the LTP, such as the Legacy Ponds and
Legacy Silos (LP&LS) schedule.
Work is being done to mitigate these risks within the individual Operating Units (OUs) on site.
Opportunities
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The IWS and supporting component strategies have identified a number of opportunities. If realised
these have the potential to further integrate and optimise the IWS.
The opportunities for LLW are largely related to initiating new processes for avoiding and minimising
the volume of LLW requiring disposal. These include techniques such as improved waste segregation
and characterisation, chemical decontamination, cracking and crushing of concrete, and cable
stripping. In addition there are considerable opportunities regarding the on site reuse and recycle of
High Volume Very Low Level Waste (HVVLLW). These are being developed via the LLW Strategy for
the Sellafield site, due in January 2009.
The opportunities for ILW involve rationalising the number of potential treatment plants and stores
required by pursuing opportunities to use existing and planned ILW treatment plants to treat additional
wastes and, in the case of stores, exploring options relating to the rate of export of waste packages to
the ILW repository.
The timescales for decisions to be taken for the different opportunities varies considerably, and is
largely dependant on the predicted schedule of waste generation.
Some of the opportunities identified within this version of the IWS have interdependencies with
decisions required to be taken at a national level, e.g. the national LLW strategy and decisions
relating to the ILW Repository. The development of a national IWS by the NDA would help to facilitate
the resolution of key uncertainties.
Future Development
The IWS will continue to develop for the foreseeable future as:
• the component strategies develop and progress
• other external influences affect the strategic direction of the site and the timing of certain key
decisions
• the interactions between strategies and the opportunities they create continue to be
optimised
In the near term, the following will influence the development of the Sellafield IWS:
1. development of national strategies, such as that for LLW, due in early 2009
2. requirement for a combined Sellafield and Windscale IWS by the end of June 2009
3. financial provision for work and projects required by the site strategy
This update of the IWS reports and discusses the tactics and deployment of the Sellafield IWS. The
component strategies will continue to implement the principles of the IWS and hence the future
1
development of the IWS will primarily be as a ‘flankguard ’ role to:
• ensure the general strategic direction is maintained, regardless of changes to tactics that
may be needed in the future
• undertake assessment of potential strategic changes initiated by resolution of uncertainties
or changes in assumptions
Paul Foster
Director Strategy and Transition
Chair of IWS Steering Group
1
‘Flankguard’ – The role of flankguard to is continuously assess all internal and external changes arising after
delivery of a strategy and their impact on the strategy and associated projects i.e. to keep the strategy “live”. It is
also to ensure that the intent of the strategy is preserved during all subsequent implementation phases. The
flankguard must also ensure the strategy is communicated to and understood by the teams carrying out the
implementation phases.
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June 2008
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Contents
EXECUTIVE SUMMARY ........................................................................................................................ 3
1.0
INTRODUCTION........................................................................................................................ 7
1.1
1.2
1.3
1.4
2.0
Sellafield Integrated Waste Strategy ........................................................................ 7
Successes in Waste Management on Sellafield Site .............................................. 10
What has changed since the previous IWS was issued in June 2007 (Version 2) .. 11
Impact of the Integrated Waste Strategy on the Sellafield Site ............................... 12
REVIEW OF PROGRESS ON THE 2007 IWS OUTPUTS...................................................... 13
2.1
2.2
3.0
The IWS 2007 Recommendations and the Progress made against them. .............. 13
Progress against the 2007 IWS (Version 2) Action Plan......................................... 22
STRATEGIC DEVELOPMENTS IMPACTING ON IWS.......................................................... 23
3.1
3.2
3.3
3.4
4.0
Other Strategic developments in the Sellafield Lifetime Plan (2008)....................... 24
Strategic Governance Arrangements ..................................................................... 26
Contaminated Land & Site End States ................................................................... 27
Integration with Windscale ..................................................................................... 28
PROGRESS MADE ON WASTE MANAGEMENT STRATEGIES ......................................... 28
4.1
Solid Wastes .......................................................................................................... 29
4.1.1
4.1.2
4.1.3
4.1.3.1
4.1.3.2
4.1.3.3
4.1.3.4
4.1.4
4.2
Update to the solid radioactive waste strategy................................................................ 29
High Level Waste (HLW) strategy ................................................................................... 31
Intermediate-Level Waste Strategy Update .................................................................... 33
Operational wastes ..................................................................................................... 33
Legacy Ponds and Legacy Silo wastes ...................................................................... 34
PCM wastes ................................................................................................................ 34
Final Treatment and Disposal of ILW.......................................................................... 35
Low Level Waste strategy ............................................................................................... 36
Aqueous Waste Strategy........................................................................................ 38
4.2.1
Sellafield Ltd’s response to the Particulate Enforcement Notice .................................... 43
4.2.2
Legacy Ponds & Legacy Silos – SIXEP Contingency Plan............................................. 43
4.2.3
Switching feeds from the Segregated Effluent Treatment Plant to the Enhanced Actinide
Removal Plant................................................................................................................................ 44
4.2.4
Future Low Active Aqueous Effluent Strategy................................................................. 46
4.2.5
Discharge Trends ............................................................................................................ 49
4.3
Gaseous Waste Strategy ....................................................................................... 50
4.3.1
4.3.2
4.3.3
4.3.4
4.4
Decommissioning................................................................................................... 52
4.4.1
4.5
Update of the Gaseous Waste Strategy.......................................................................... 50
Separation Area Ventilation Project ................................................................................ 50
Alpha Plant Discharge Stack........................................................................................... 51
Discharge Trends ............................................................................................................ 51
Decommissioning Strategy (including mandates) ........................................................... 52
Non-Radioactive Discharges .................................................................................. 53
5.0
OPPORTUNITIES, RISKS & UNCERTAINTIES..................................................................... 54
6.0
CONCLUSIONS & WAY FORWARD...................................................................................... 55
7.0
GLOSSARY ............................................................................................................................. 59
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1.0
Introduction
1.
This report is the third annual issue of the Integrated Waste Strategy (IWS) for Sellafield. It has been
written as an addendum to the 2007 IWS (Version 2) and reports progress against the recommendations
made in the 2007 IWS, recent developments in strategic governance arrangements for the Sellafield site,
the latest waste strategies, and waste and effluent arisings data. As such, it should be read in conjunction
with the 2007 IWS (Version 2) in order to fully understand the context of the information presented herein.
2.
The delivery of an IWS for the Sellafield site is a formal requirement of Schedule 9 of the Radioactive
Substances Act Authorisation (RSA 93) and helps demonstrate compliance with the Nuclear Site Licence,
in particular Condition 32.
3.
The Nuclear Decommissioning Authority (NDA) is responsible for the liabilities of UK public sector civil
nuclear sites. The NDA requires each Site Licence Company (SLC) to produce an IWS; this should act as
a tool for the site operators to optimise their site-wide approach to waste management. The NDA aims of
the IWS are to:
Protect people and the environment and respond to stakeholder concerns
Make the most effective use of existing waste management facilities
Provide value for money for the UK taxpayer
Provide the link to the rationale behind the waste aspects of the site’s Lifetime Plan (LTP)
submission
Provide a framework for optimising the approaches to waste management on a site-wide basis.
4.
It is the intention that the strategies set out in the individual site IWS reports will be rolled-up by the NDA at
a national level and will be subject to periodic review. This will enable the NDA to identify strategic issues
at both site and national level and thus to develop appropriate plans for the resolution of these issues.
1.1
Sellafield Integrated Waste Strategy
The Sellafield IWS Vision is:
5.
An Integrated Waste Strategy will deliver an operating site that has minimised waste generation
and where waste is generated, it is contained in a manner that achieves sustainability; where
sustainability is waste in a form that requires ideally nil, but probably minimal, management to
safely protect people and environment including the remediation of historical impacts.
6.
In addition to fulfilling the aims of the NDA given in paragraph 3 above, it is the goal of the Sellafield site to
transform the IWS into a functional everyday aid for the strategy team and site management, and hence to
the site for running our business. With this in mind, the IWS issued in June 2007 (Version 2) was
developed with the following aims:
a) to provide a consistent and proportionate overview of all wastes on site ensuring that the Waste
Management Hierarchy (WMH) is applied wherever practicable and due consideration is given to the
interaction between environmental protection and urgent hazard reduction;
b) to envisage how the site waste routings will develop over time;
c) by means of b), to identify bottlenecks in waste handling and to open up new waste routes where
appropriate;
d) to produce a Decision Calendar for the new facilities suggested by c);
e) to encourage the shift in behaviours necessary to get the new waste routes in use at the working level;
f) to facilitate customer, Regulator and stakeholder engagement.
7.
The rate of progress in implementing the IWS is influenced by:
• the need to be consistent with a higher strategic driver for the site of ‘hazard and environmental risk
reduction’;
• affordability of the implementation plan in any given period.
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8.
IWS Version 2 addressed these aims via a structured process of applying the WMH and using Sankey
2
Diagrams to identify areas for improvement. The process inherently recognises the priorities of safety and
3
risk reduction and applies the NDA Prioritisation Logic , the WMH and the principles of Engineered
4
Destinations . Full details of this process can be found in section 7 of the IWS issued in June 2007
(Version 2).
9.
By following this structured process and embedding the outputs of this into the LTP (see section 1.4 of this
report) the site has made significant progress towards its goal of transforming the IWS into a functional
everyday aid for the strategy team and hence to the site for running our business and addressing the aims
a) – f) given above.
10.
Sellafield site comprises more than 200 nuclear facilities, in various different stages of building life, from
operations to decommissioning, and with some new plants under construction to enable the site to deal
with legacy wastes. Sellafield is a key part of the nuclear fuel cycle. The size and complexity of the site and
the wide range of wastes inevitably means that the corresponding waste strategies and management
arrangements are multifaceted, requiring significant effort to become truly integrated and optimised. The
IWS is a component part of the Integrated Strategy for Sellafield, and the links between component
strategies and external influences is shown in Figure 1 below, which also highlights the strategies that
come under the ‘IWS’ banner.
2
Sankey Diagrams have been used to illustrate the waste arisings at key snapshots in time and the currently identified
routings for these wastes. The concept of Sankey Diagrams is described as; the thickness of the lines is representative of the
(volumetric) flows of the waste, and the relative size of the ‘arrows’ on the diagrams represents the waste treatment plant
throughput capacity for the given year. From this, bottlenecks and waste routes are visually easy to assess.
3
The Energy Act, and the NDA Management Statement and Financial Memorandum, places requirements on the NDA in
respect to performance reporting, openness and transparency, and for ensuring that the rationale for major decisions, and the
processes by which they are reached, are clear to stakeholders and the wider public. One of the ways in which the NDA
achieves this is by a national process for work prioritisation. This is used as an aid to the effective scheduling of remediation
work optimising the SLC delivery against the Site Funding Limit (SFL), and to assess alternative delivery strategies. As such
the Prioritisation Process has been designed as an aid to decision making, which supports the development of the Life Time
Plan (LTP). For further information refer to the NDA website, www.nda.gov.uk
4
Engineered Destinations: The final form (solid, aqueous, gaseous) of radioactivity determines the environmental impact
arising from that waste. Ideally the activity is retained within a form that offers maximum ‘barriers to the biosphere’ i.e. an
engineered form that limits the pathways for discharge to the environment. In practice this means that generally the
preference is for activity to be captured in the solid form rather than aqueous form which is in turn preferred to the gaseous
form. Unintentional, uncontrolled discharge to ground must be avoided.
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Figure 1 – The interaction between site strategies, the IWS and external influences from UK and NDA
policies
11.
The methodology followed in the 2007 IWS, that was built on the baseline position established the
previous year, has given the site confidence that based on current assumptions it has successfully
identified:
• its wastes inventory and arisings profiles
• their routings and any potential bottlenecks
• the potential new plants and routes required to appropriately treat and dispose of these wastes
These findings have been implemented as appropriate into the LTP developed for the site.
12.
The Sellafield IWS is still progressing towards being fully integrated and optimised and will continue to do
so for the foreseeable future as:
• the component strategies develop and progress
• other external influences affect the strategic direction of the site and the timing of certain key decisions
• the interactions between strategies and the opportunities they create continue to be optimised
13.
This is illustrated in Figure 2 below, which explains how the Sellafield IWS report has developed through a
number of stages. Initially, a baseline position (produced in 2006) where objectives and inventory were
identified, together with a basic strategy. This progressed through to an analytical tool (IWS Version 2
2007) that assessed waste routes and identified bottlenecks and opportunities for improving application of
the WMH to give a more developed strategy and some tactical application of this. This report represents
the current position, which is a summary of how the IWS has been tactically deployed on the site at the
working level and the changes this has engendered (2008, this report).
14.
The tactical deployment has been achieved by the IWS team and the wider Strategy Group through
addressing the recommendations of the 2007 IWS, attending strategy meetings, engaging with
stakeholders, and encouraging work streams and projects to adopt the principles identified in the 2007
IWS.
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Figure 2 – The development and progression of the IWS
15.
It has been recognised that owing to the complexity of the Sellafield site and associated wastes and waste
routes that it will take a number of years to produce an optimised and fully integrated strategy for wastes.
This report therefore provides an update in the steps towards a fully integrated and optimised waste
strategy.
16.
This addendum reports the progress since the issue of Version 2 (June 2007) and discusses:
• how component waste strategies have developed since Version 2
• the impact that IWS Version 2 had on the plans and strategies included in the 2008 LTP
• new drivers that have gained prominence since the IWS was last reported.
1.2
Successes in Waste Management on Sellafield Site
17.
Significant amounts of waste have successfully been treated at Sellafield, thus greatly reducing hazard,
volume, and risk, resulting in a much lower environmental impact. This demonstrates the benefits of waste
management planning which are being further strengthened through deploying an IWS.
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18.
Examples of recent successes in waste management include:
900te of metals have been decontaminated via the Wheelabration process. The metal is
assessed and characterised as suitable for exemption under RSA 93, then shot blasted to
remove surface films down to bare metal. Further reassurance monitoring is carried out prior to
release to a scrap metal dealer for recycling.
The Wheelabrator safety case has been successfully modified to further allow the processing
(and hence decontamination) of stainless-steels.
Clearance and characterisation of Thorp Medium Active Salt-Free Evaporator (MASFE) wastes –
Improved characterisation enabled declassification of the waste, which meant that the waste
could go to landfill or the Low Level Waste Repository (LLWR) as appropriate, saving £100,000
Characterisation of the asbestos from the decommissioning the Calder Hall power station heat
exchangers – the entire waste stream was successfully characterised for exemption under RSA
93 through appropriate sampling. This therefore negates the need for monitoring every single bag
of waste.
Completion of waste oil treatment and disposal trials – Oil incineration at Studsvik (a specialist
waste disposal company), established the process viability. Thermal energy produced during the
incineration was used to heat the buildings on the Studsvik site (energy recovery).
Public engagement has taken place concerning the treatment of Low Level Waste (LLW);
covering Oils, Metal, Asbestos, Process Waste and High Volume Low Active (HVLA) wastes.
Individual stakeholder engagement sessions were held (presentations, questionnaires and final
reports are on the “Consultations” area of the Sellafield Ltd Web Site
www.sellafieldsites.com/page/corporate-responsibility/stakeholder-engagement/consultations)
Achieved >65% packing efficiency overall for LLW containers sent to LLWR for all containers
where appropriate infill material was available. This reduces the amount of clean grout used at
the LLWR and improves the utilisation of the space in the LLWR
Recycling of Fluorescent Tubes via monitoring and using a waste contractor rather than crushing
and disposing to the LLWR – trialled and now this good practice in one part of the site is being
applied site-wide (where applicable).
Improved waste concentration rates in the Enhanced Actinide Removal Plant (EARP) provide a
significant (20-30%) reduction in the future lifetime arisings of the associated Intermediate Level
Waste (ILW) packages produced. This also helps to secure the ongoing processing schedule of
historic waste recovery through the EARP process.
19.
1.3
In recognition of the magnitude of the decommissioning task facing Sellafield site, a database has been
developed to centralise individual decommissioning project information to look for trends. As the
information is amassed, it should be possible to improve predictions of waste volumes for future
decommissioning and demolition projects, and enable assessment of these against the capability of the
various treatment and disposal routes. The database aims to provide gains in the key areas of data
defensibility, data applicability, data collection, cost savings and data collection timelines. The database
will include access to real-time links of underpinning information and will have an ability to identify
programme or project constraints and measure their impacts.
What has changed since the previous IWS was issued in June 2007 (Version 2)
20.
Since the previous IWS was issued in June 2007 (Version 2), there have been significant external
influences upon the Sellafield site and subsequently upon the Integrated Waste Strategy.
21.
A 7 Point Plan has been agreed between the NDA and Sellafield Ltd to act as a route map in preparation
for the transition to a new Parent Body Organisation (PBO) for the Sellafield site. This included a work
stream aimed at improving the arrangements for hazard reduction and the implementation of an integrated
strategy between the NDA and the SLC. The 7 Point Plan is the high-level short-term strategy for the
business, and is essentially a collection of work streams, many of which are already underway. These
work streams have been jointly agreed by Sellafield Ltd Executive and the NDA as areas important to the
success of the business both today and into the future. Whilst this plan does not cover all existing activities
across Sellafield Ltd, these are those elements which have been identified by the executive team as
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having key strategic significance. The successful execution of the 7 Point Plan will result in improvements
in all areas of the business, in particular in nuclear, radiological, conventional and environmental safety.
The elements that are most pertinent to the IWS are those involving improvements in strategic planning
and governance.
22.
Previously (in Version 2, published in 2007), it was noted that the IWS is a subset of the Integrated
Strategy for Sellafield and as such is influenced by constraints and dependencies arising from:
Financial provisions – The NDA own the liabilities of the Sellafield site, with the SLC (Sellafield Ltd)
operating the facilities on the site and decommissioning areas of the site under contract to, and on
behalf of, the NDA. The NDA is funded by the Treasury of the UK Government, and is subject to the
government comprehensive spending review. As such the cost of decommissioning the Sellafield site
is ultimately borne by the UK taxpayer. The plans submitted to the NDA for operating and
decommissioning the Sellafield site are known as the “LTP”, and have been produced on a yearly
basis for the last 4 years.
Timing – The complexity and multifaceted aspect of the Sellafield site ensures that the timing and
scheduling of plant operations, decommissioning, waste retrieval, infrastructure, and new-build projects
all have cross-connections and subsequent influences upon each other. Therefore even relatively
basic changes to one aspect of strategy or operational scheduling can have a profound impact across
many areas of the Sellafield site.
Technical – The Sellafield site is one of the most complex and crowded nuclear sites in the world, and
to ensure continued excellence in nuclear safety and nuclear material management requires significant
technical expertise and understanding. There are a number of technical constraints associated with
radioactive waste management and as such these have an influence upon the Sellafield IWS.
Transport strategies – Moving raw and conditioned waste around the site as required for treatment or
storage, and exporting waste to repositories for disposal as appropriate.
Ongoing strategy development for Site End States & Contaminated Land – The final end state(s)
for the Sellafield site and the extent to which any contaminated land is treated or excavated for
treatment will have a large impact on the Sellafield IWS.
23.
There have been significant developments in several of these areas, notably:
Financial provisions – The funding that has been made available to the site is insufficient to fully
deliver the planned scope of work. As a consequence, the site is re-evaluating its LTP against the
available funding profile.
Timing - Work programmes have altered & extended to take into account the funding constraints.
Technical – Technical challenges on the High Active (HA) Evaporators are presently constraining the
throughput & capacity of upstream plants and have extended the Thorp and Magnox reprocessing
dates, causing subsequent changes in the timing of other supporting strategies.
This report explores these developments and reports the consequential impacts on the IWS in section 3.
24.
The future development of the IWS will continue to be informed by the outcome of work that is currently
ongoing to better define and resolve these uncertainties.
1.4
Impact of the Integrated Waste Strategy on the Sellafield Site
25.
The recommendations and findings made by the IWS Version 2 (issued June 2007) have been
implemented into the future work planned on the Sellafield site through the LTP process. A short list of
some of the most relevant is provided here:
Volume reduction facilities, expansion of the LLW decontamination capacity and opportunities for High
Volume Very Low Level Waste (HVVLLW) reuse/recycle are being progressed by the developing LLW
strategy.
Sort & Segregation and decontamination opportunities for ILW are included within the Final Treatment
and Disposal of ILW Operating Unit (OU).
Two options studies (as detailed in section 2.1) were delivered and will inform both the LLW and ILW
strategies for the site.
26.
The IWS has also informed some future Research & Development (R&D) requirements of the site. These
can be found in the site’s Technical Baseline Underpinning Research & Development (TBURD). A short list
of some of the most relevant R&D Tasks is provided here:
Improved waste characterisation & radiometric segregation and sorting is required.
Source decontamination methods to increase amount of ventilation ductwork sent as LLW instead of
Plutonium Contaminated Material (PCM).
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Determine the depth of contamination in mild and stainless steels and explore methods of
decontaminating stainless steel.
Identify techniques / technologies for reducing volumes of contaminated soil requiring disposal.
Size reduction / alternative routing for non-compactable materials.
Underpinning studies for LLW Incineration.
Underpinning studies relevant to encapsulation of reactive metals.
Assessment of the feasibility of decontaminating ex-Decommissioning ILW.
Investigate means to minimise decommissioning ILW product yields i.e. active grouted ILW, and coconditioning of slurry and bulk ILW.
Investigate In-cell segregation of LLW from ILW.
Investigate the compaction of waste filters to reduce packing space.
Develop instrumentation to characterise cell concrete for ‘free release’.
It should be noted that constraints on funding are likely to impact upon the R&D described here and in the
TBURD and hence prioritisation of the R&D carried out may mean some or all of these are delayed or
cancelled.
2.0
Review of Progress on the 2007 IWS Outputs
27.
Improvements were identified within the IWS Version 2 process and these came in two forms, firstly a
series of key recommendations for improvement, and secondly an action plan to deliver them. The action
plan, whilst taking note of the key recommendations, has been influenced further by RSA 93 authorisation
requirements, NDA Performance Based Incentive (PBI) S003-07/08-35-15 for Sellafield site, and other
findings from the IWS Version 2 process, for example, review by the Integrated Waste Strategy Steering
Group (IWSSG).
28.
This section reports on the progress made in relation to the various recommendations. The work done on
each recommendation is discussed together with a summary of the progress made by the site.
2.1
The IWS 2007 Recommendations and the Progress made against them.
29.
Recommendation 1:
Develop and trial a structured process for WMH application within Decommissioning Mandates
30.
Progress Made:
Decommissioning Mandates have been carried out on 22 plants to date, including the major facilities on
site. As part of the mandates, waste quantities have been assessed and the output of the mandates is
currently being reviewed, including an assessment of sensitivities of waste volumes and waste treatment
options. The contract for the Decommissioning Mandates was already in place when this recommendation
was made in the 2007 IWS (Version 2). Therefore, the site was unable to impose this additional work on
the mandates due to commercial constraints. Currently no further Decommissioning Mandates are planned
for Financial Year 08/09. This recommendation is therefore on hold while the way forward with the
Mandates is determined.
31.
Recommendation 2:
Carry out a review to establish optimum scrubber liquor routing & treatment of current Segregated
Effluent Treatment Plant (SETP) routed liquors
32.
Progress Made:
After verifying that no such review had historically taken place, a ‘Scrubber Particulate’ Workshop was
organised to bring together the technical expertise of the various OUs which operate scrubbers at
Sellafield, independent engineering expertise within Process Engineering, Nuclear Ventilation Design
Group and the IWS.
33.
The purpose of the workshop was to ascertain whether particulates present an issue for the individual
scrubber liquor streams, and if so consider alternatives to optimise the routing. The key conclusions are
summarised below:
1. There are no target or success criteria by which to judge the acceptability of particulates in scrubber
liquor sent to SETP.
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2. It is not practical to effectively sample for very small levels of particulate in the relatively large scrubber
bleed streams.
3. Prediction of particulates in scrubber liquor based on source terms can only be done on a worst case
basis.
34.
Actions were placed against those OUs where a scrubber wasn’t represented at the workshop or where
further information on a particular scrubber system is required to confirm that robust Best Practicable
Means (BPM) are in force. A summary report will be produced, to include the programme of work to further
progress this issue.
35.
Recommendation 3:
Establish robust characterisation and capability to sort and segregate LLW and ILW waste from
decommissioning
36.
Progress Made:
There is a significant quantity of waste scheduled to arise from decommissioning. Current estimates
3
3
3
indicate approximately 891,000 m of LLW, 66,000 m of ILW and 1,408,000 m of Very Low Level Waste
(VLLW) to arise through decommissioning over the remaining lifetime of the site.
37.
There is a strong driver to have appropriate segregation of materials at the decommissioning workface and
to avoid mixing wastes in the first instance. This is especially applicable during decommissioning activities
where the volumes are large and the potential for waste segregation exists. The projected volumes of
decommissioning wastes have been revised based on information from some of the recently completed
decommissioning mandates. These mandates assume techniques to decommission specific plants and
assess the associated cost and projected waste volumes using one set of assumptions. Subsequent work
on the mandates will assess the range of techniques, volumes, costs & timescales which may be may be
adopted for decommissioning in practice.
38.
Recognising the large volumes of wastes projected to arise over the lifetime of the site, the LLW
Management OU has included the concept of new-build facilities (subject to selection of the Best
Practicable Environmental Option (BPEO)) within its 2008 LTP assumptions. These facilities will enable a
greater degree of waste minimisation (although the new build will in itself produce waste, the overall long
term impact will be a net reduction in waste) in order to reduce the total volume consigned to the current
LLWR and successor facility. A series of public consultations have taken place as a preliminary
investigation of these concepts. Within these conceptual new-build facilities, a sort and segregation
capability is included that will segregate waste both radio-metrically and by material type. The facility is to
also include segregation of wastes not only from decommissioning but also from operational and Post
Operational Clean Out (POCO) activities.
39.
The LLW sort and segregation facility is assumed to become operational in 2020 and is being further
developed as part of the LLW strategy which will be published in January 2009. It is currently the intent
that the facility should be able to segregate wastes that are suitable for:
Thermal treatment,
Melting / smelting,
Low Force Compaction,
Non-compactable wastes,
Metals suitable for mechanical decontamination (wheelabration),
EXEMPT materials.
40.
Appropriate segregation of ILW by material type is included within the scope of the Final Treatment and
Disposal of ILW strategy. The degree of segregation required is mainly driven by the extent to which it is
necessary in order to achieve a suitable final waste product for disposal. Volume reduction is currently
assumed to be an opportunity in the Final Treatment and Disposal of ILW OU strategy.
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41.
It is worth noting that the two IWS Option Studies produced both highlighted the need for robust
characterisation and the capability to sort & segregate waste. This was further reiterated in the output from
the series of public engagement workshops on LLW that have taken place since the IWS Version 2 was
issued.
42.
Recommendation 4:
Ensure the re-use and recycling of materials such as
High Volume VLLW and cables and switchgear
generated from decommissioning
43.
Progress Made:
This recommendation has been addressed by the
completion of an option study, specifically looking into the
reuse and recycle of HVVLLW. Focus was given to
HVVLLW arising from decommissioning, for example
concrete, rubble and metals. Cables and switchgear were
left outside the scope of the option study, since the
volumes generated were considerably less than the other
material types.
44.
Over the lifetime of the site, it is predicted that 1.4M m of
HVVLLW will be generated. HVVLLW is defined as
radioactive waste that has an activity lying between the
exemption level of 0.4 Bq/g, and 4 Bq/g. At present all
HVVLLW generated is to be disposed of to a specified
landfill, as stated in 2007 LTP. There are both commercial
and ethical incentives for the investigation of potential
routes that will enable reuse or recycling of this waste.
Largely speaking, these entail being able to prevent costly
disposal, whilst preserving the environment from the
impact of transportation of the waste on such a large
scale. In a strategic sense, there is therefore considerable
scope for the improved application of the waste
management hierarchy.
3
Located here
for illustrative
purposes
Figure 3 – Sellafield site, yellow circle indicates
the volume of land needed for the disposal of all
HVVLLW, assumed depth of 10m
45.
The intention of the option study was to evaluate a range
of possible scenarios and thus recommend a viable case for further waste route development, whilst also
informing future strategic thinking. The three scenarios investigated are provided below. This enabled the
issue to be bounded; scenarios 1 and 3 are the two extremes of either doing the minimum possible or
doing everything to reuse / recycle waste. Scenario 2 is the “middle ground”, whereby HVVLLW would be
recycled wherever practicable, though with an option for waste to be disposed off-site to a specified landfill
as necessary.
46.
Scenarios
1.
Disposal of all HVVLLW to specified landfill (Current situation remains the same)
2.
A combination of reusing and recycling HVVLLW on site, and the disposal of waste to a specified
landfill if deemed necessary
3.
All HVVLLW to be reused or recycled on site, with no disposal to off-site landfill
47.
From here, the scenarios were critically assessed, investigating practicable routes in which to implement
the particular scenario. The assessment would be made both quantitatively and qualitatively, against a
number of metrics; these were Cost & Schedule, Security, Safety and Environmental Impact. Table 1 gives
the specific details and comparative costs of each of the scenarios.
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48.
From the investigation, it became apparent that there was not significant variation in the overall costs
associated with the different scenarios. It should be remembered that these costs are indicative only, and
are not a detailed costing or business case. Furthermore, it was realised that certain variables were
responsible for a major proportion of the costs, for example the predicted cost of characterisation. This led
to the first recommendation of the IWS option study, as summarised below. The option study has been
developed alongside a spreadsheet, which has been used as a tool to construct the quantitative argument.
The
spreadsheet
has
been
developed
with
an
inherent
level
of
Table 1 – Summary of the details and indicative cost of each scenario
flexibility, allowing for change and
Scenario
Details
Costs
progress to be incorporated in the
Calder Landfill Extension Segregated
5
1
future, thus ensuring the option
Areas (CLESA) filled and then all waste to £1257M
Specified Landfill, 150 km to site
study is a robust, adaptable, and onSegregating exempt from HVVLLW. All
going process.
2
exempt reused on site, HVVLLW disposed
of to CLESA and then specified landfill
Segregating exempt from HVVLLW. All
exempt reused on site, HVVLLW used as
sea defences and end state landscaping
Segregating exempt from HVVLLW. All
exempt reused on site, all HVVLLW used
as end state landscaping
Segregating exempt from HVVLLW. All
exempt reused on site, all HVVLLW used
as LLWR capping
£1060M
It was concluded that potential
reuse/recycle routes that did not
3a
£1078M
involve
further
characterisation
would be financially beneficial. This
may include using HVVLLW as
3b
£1094M
capping material for the LLWR or as
landscaping
material
for
the
£1019M
3c
implementation of the end-state
vision of Sellafield. There is scope
for all HVVLLW to be used in some
form on Sellafield site, for this reason it was concluded that all HVVLLW should remain on site. By doing
do this would mitigate the considerable transport, environmental and safety implications associated with
transporting the waste off site. A list of some of the key recommendations to come out of the option study
are provided below:
•
•
•
•
49.
Identify and minimise the true costs of waste characterisation, as they currently form the most significant
cost in all strategic options for the reuse and recycle of HVVLLW.
A detailed assessment of the amount of waste exemption that would be achieved through improved
waste characterisation should be undertaken.
Assess the statistical risk of reuse and disposal on-site for comparison against the risk from transporting
all HVVLLW to an off-site specified landfill.
Investigate the potential use of Sellafield HVVLLW concrete and rubble as capping material for the
LLWR.
50.
The output of this options study is being used to inform the developing LLW Strategy.
51.
Recommendation 5:
Increase the Sellafield waste volume reduction capability
52.
Progress Made:
The 2008 LTP strategy for LLW includes a suite of new-build treatment facilities that are assumed to
commence operations in 2020. These facilities are intended to provide a greater degree of volume
reduction than that which currently exists on the site and hence will minimise the overall quantity for
disposal to the LLWR or successor facility. The facilities are also assumed to generate waste products that
will comply with the LLWR conditions for acceptance.
53.
The LLW facilities that are to achieve significant volume reduction are as follows:
Continued use of the Waste Materials and Compaction (WAMAC) facility for high force compaction of
compactable LLW until 2020,
A new facility for Thermal destruction of suitable LLW from 2020 onwards,
A new facility for Melting / Smelting of suitable LLW from 2020 onwards,
5
CLESA is an area of Sellafield site that is treated as a landfill for low activity waste. The capacity is limited to 100,000 m3,
and the activity limit of acceptable materials is 37 Bq/g
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A new facility for Low Force Compaction of any compactable LLW that cannot be processed via the
above facilities,
Continued use of mechanical decontamination of LLW in the form of the current wheelabrator
54.
Early analysis carried out as part of the 2008 LTP strategy development for LLW indicates that the impact
from the new facilities results in approximately 19,300 fewer Half Height International Standards
Organisation (HHISO) freights required for disposal over the lifetime of the site. This is illustrated in Figure
14 in Section 4.1.4 of this report.
55.
Volume reduction of PCM is currently achieved through high force compaction via the current Waste
Treatment Complex (WTC)1a facility. The 2008 LTP strategy for PCM includes a new PCM treatment
complex for processing any PCM wastes that are not suitable for the current compaction process in
WTC1a. The process for the new treatment complex has not yet been finalised and the primary driver will
be to achieve a safe and passive waste product suitable for repository disposal. Volume reduction potential
will also be considered in the selection of the final process.
56.
Similarly, the primary driver for the ILW strategy is to achieve a safe and passive waste product suitable for
repository disposal. Volume reduction is currently included as an opportunity and is being investigated as
part of the strategy for the Final Treatment and Disposal of ILW OU.
57.
Recommendation 6:
Perform a Study on Passivation Requirements and Alternative Encapsulants for ILW
58.
Progress Made:
This recommendation has been captured within the TBURD. This means that the need for specific
research and development to resolve this issue has been identified in a key document underpinning the
LTP.
59.
This has been extracted from the TBURD section of the Sellafield LTP and repeated here for ease of
viewing.
Technical need – Task +
gap
Optimising OPC (Ordinary
Portland
Cement)
grout
formulations
Identify optimum OPC grout
formulations
for
each
characteristic type of ILW within
the scope of the Final
Treatment and Disposal of ILW
OU.
Alternative ILW encapsulants
Identify
and
characterise
potential
alternative
encapsulants
per
each
fundamental ILW type to be
encountered within the scope of
the Final Treatment and
Disposal of ILW OU
Context of why a problem (driver)
Whilst OPC-based grout is the baseline ILW
encapsulation medium, the term encompasses a
wide range of OPC grades with and without
additives (plasticizers, BFS, PFA etc).
The process of identifying
formulations
per
waste
characterisation of alternatives.
Whilst historically, OPC-based encapsulation
matrices have been widely used for the
conditioning of ILW, there are a number of
drivers to develop comprehensive appreciation
of alternative media – these include the potential
need for:•
encapsulants accommodating of wastes
comprising / containing reactive materials
and/or organics – in order to obviate /
minimise the need for prior passivation of the
wastes
•
encapsulants yielding low-leach wasteforms
– noting that leach rate might become a key
repository criterion with regard to meeting
the Post Closure Report Safety Assessment
(PCRSA) risk target or otherwise in order to
justify BPM – particularly in respect of
radionuclides that dominate the PCRSA
•
encapsulants with low thermal fracture
potential due to waste decay heat –
Potential
alternative
encapsulants include:
OPC-based,
other mineral-based,
thermoplastic polymer,
thermosetting polymer,
bitumastic,
vitreous,
white metal,
noble metal.
Required characterisation data
suitable OPC
type
entails
Target Date
Key outputs / Actions
Exercise
starts
beginning 2010/11 and
completes end 2012/13
(3 years total)
Technical report
(+
underpinning analysis
and
experimental
results) recommending
definitive OPC grout
formulations per each
Final Treatment and
Disposal of ILW OU
waste type
Target date basis =
critical path to inform
design of 1st
ILW
treatment plant
Exercise
starts
beginning 2010/11 and
completes end 2014/15
(5 years total)
Target date basis =
critical path to inform
ILW
design of 1st
treatment plant
Technical report
(+
underpinning analysis
and
experimental
results)
confirming
suitable
alternative
encapsulants per each
Final Treatment and
Disposal of ILW OU
waste type
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Technical need – Task +
gap
Context of why a problem (driver)
per encapsulant will include:-
particular relevance is to irradiated U fuel
residues. (Thermal fracture reduces product
integrity pre-disposal and increases inrepository leach rate due to increase in
specific surface)
1.
2.
3.
4.
5.
6.
7.
ingredient costs
ingredient availability
ingredient shelf life
method(s) of preparation
method(s) of deployment
flow characteristics
incorporation limits vs.
waste type
8. pre-cure
/
post-cure
reactivity vs. waste type
9. performance sensitivity
10. curing characteristics
11. properties of cured matrix
Alternative
techniques
encapsulation
Determine
practicable
alternative
encapsulation
techniques for each perm of
fundamental ILW type vs. viable
encapsulant as determined at
Final Treatment and Disposal of
ILW-TB-RD3
•
encapsulants with high tensile strength and /
or low potential for chronic expansive
reaction (within matrix or between matrix and
waste) - thereby being resistive to matrix
fracture
(Matrix fracture reduces product integrity
pre-disposal and increases in-repository
leach rate
due to increase in specific
surface)
•
alternatives to OPC-base encapsulants
should topical ingredients become scarce
Gravity percolation (with/without vibro-assist)
and paddle mixing – are the only two ILW
encapsulation techniques that have been
developed and implemented at Sellafield – in
either
case
unplasticised
OPC
based
encapsulants are used and waste feeds limited
to:• fuel-element cladding (swarf and hulls
etc.) and ferrous engineering scrap ex
magnox and oxide reprocessing
• acid and alkaline slurries ex oxide
reprocessing
• flocs ex treatment of site liquid
effluents
Target Date
Key outputs / Actions
Exercise
starts
beginning 2010/11 and
completes end 2012/13
(3 years total)
Technical report
(+
underpinning analysis
and
experimental
results)
identifying
practicable alternative
encapsulation
techniques for each
perm of fundamental
ILW
type
vs.
encapsulant
as
determined at Final
Treatment and Disposal
of ILW OU - TB-RD3
Target date basis =
critical path to inform
design of 1st
ILW
treatment plant
New capital facilities will be required to effect the
conditioning of:• the lifetime inventory of the Miscellaneous
Beta Gamma Waste Store (MBGWS)
• the lifetime inventory of AGR (Advanced
Gas Reactor) graphite and stainless steel
• ex decommissioning ILW arisings up to
the site end state
- with encapsulation likely to be the predominant
method employed. In this regard and in order to
facilitate the specification and design of the new
facilities,
an
objective
appreciation
of
practicable alternative encapsulation techniques
vs. waste types vs. encapsulants is required.
60.
As noted previously, constraints on funding are likely to impact on the R&D that is performed, and the
subsequent prioritisation of R&D work may mean some of all of these are deferred or cancelled.
61.
Recommendation 7:
Widen the envelope of the current LLW decontamination facility
62.
Progress Made:
63.
The current LLW metal decontamination capability on Sellafield site is in the form of two dry abrasive
decontamination facilities (wheelabrators). One of which has been successfully decontaminating metals to
the exemption levels, as specified by the RSA 1993, for the last ten years. The second wheelabrator
gained the appropriate authorisation to accept, and thus decontaminate metals of confirmed contamination
in November 2007. At which point both wheelabrators were now able to decontaminate metals from C2
2
2
Controlled Area levels of contamination (4 to 40 Bq/cm β, or 0.4 to 4 Bq/cm α – note that this is a
measure of surface area contamination) down to exempt levels (0.4Bq/g), this demonstrates an increased
capacity for LLW decontamination. The wheelabrators use a method of shot-blasting (an example of
mechanical abrasion) to decontaminate metallic objects of simple geometries (Figure 4). In addition to this,
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there is the ability for size reduction, using both cold and hot cutting techniques. Size reduction is used
ensure that the metal objects are of a geometry that is acceptable for the wheelabrator process.
Figure 4 – Pieces of metal before and after treatment (top and bottom left), one of the current
wheelabrator facilities on site (right).
64.
Due to the schedule of waste arising, the amount of stainless steel being generated as a result of
decommissioning activities is increasing. Fuel storage pond furniture, such as the frames that hold MultiElement Bottles (MEBs), forms the majority of stainless steel waste. The increasing generation of stainless
steel wastes has provided the motivation to widen the scope of the wheelabrator size reduction capability.
Currently only cold cutting is permitted for stainless steel because of the potential hazard of chromium
inhalation. It is anticipated that a Plant Modification Proposal (PMP) will be prepared that will substantiate
the facility’s ventilation system against the increased hazard posed by chromium within the stainless steel.
65.
The increased demand for decontaminating stainless steel has brought to light difficulties regarding the
shot blast media currently used. Due to the nature of stainless steel, contamination can lie much deeper in
the surface than for carbon or mild steel. For this reason the grit needs to be more abrasive. Currently,
there are trials taking place investigating alternative shot blast media (grit). There is a high level of
confidence regarding the potential success of these trials.
66.
By the end of the year it is hoped that a minimum of 80 tonnes of stainless steel will released as clean or
exempt waste. The increased volume of stainless steel being process by the wheelabrator has no effect on
the cost of process or overall throughput. It should be noted that stainless steel is able to be sold for
roughly £750 per tonne once decontaminated, as opposed to around £70 per tonne for other ferrous
metals. This has a significant positive impact on the net cost of the process.
67.
The potential for chemical decontamination of metals is currently identified as an opportunity in the site’s
developing LLW strategy.
68.
Recommendation 8:
Carry out a Decontamination Option Study including assessment of electro-chemical techniques
69.
Progress Made:
The objective of the study was to review and assess the varying techniques for decontamination and thus
inform future strategy development for the management of contaminated metals. The focus of the study
was placed upon decontaminating LLW metals to become exempt from regulatory control. LLW is
classified as waste that contains less than 12,000 Bq/g of beta/gamma activity (or 4,000 Bq/g Alpha),
whilst any waste with less that 0.4 Bq/g of activity is classed as exempt. If proved successful, there was
the potential for the process to be applied to ILW metals.
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70.
At present a wheelabrator is used, however the capacity is currently limited by type of metal and geometry
of waste handled. The motivation for improved decontamination is based on the preservation of capacity at
the LLWR; in addition it is compliant with the WMH and can potentially lead to commercial gains from
avoiding costly disposal and the resale of clean metals.
71.
Figure 5 gives an indication of the volumes of LLW
metals likely to be generated over the lifetime of the
3
site. An estimated 460,000 m of LLW metals are to be
produced, the vast majority of which will be carbon and
mild steel, as shown in Figure 6. Approximately 92% of
all LLW metals will be carbon and mild steel, other
metals such as stainless steel, aluminium, lead, zinc
and copper contribute to the remaining 8%.
Figure 5
18,000
500,000
16,000
450,000
400,000
14,000
Annual Volume (m 3)
300,000
10,000
250,000
8,000
200,000
6,000
The study was bound by three scenarios. This gave the
study focus, from which the merits of each could be
analysed. The three scenarios studied are shown
below. Scenarios 1 and 3 are the extremes, whereby
either the current situation remains or all waste metal
are decontaminated. Scenario two is a compromise, in
which the metal is decontaminated where practicable,
however disposal is still an option.
1.
2.
3.
Capability for decontamination remains the same
as present - combination of current wheelabrator
and disposal techniques.
Employ decontamination techniques to treat LLW
to exempt where practicable and if possible, ILW
to LLW or exempt.
All metal waste to be decontaminated from ILW
to LLW and then through to exempt.
150,000
4,000
100,000
2,000
50,000
0
0
20
07
20 / 08
11
20 / 12
15
20 / 16
19
20 / 20
23
20 / 24
27
20 / 28
31
20 / 32
35
20 / 36
39
20 / 40
43
20 / 44
47
20 / 48
51
20 / 52
55
20 / 56
59
20 / 60
63
20 / 64
67
20 / 68
71
20 / 72
75
20 / 76
79
20 / 80
83
20 / 84
87
20 / 88
91
20 / 92
95
20 / 96
99
21 / 00
03
21 / 04
07
21 / 08
11
21 / 12
15
21 / 16
19
/2
0
72.
Financial Year
Metal
Figure 6
Other
28
0.007%
Carbon and Mild Steel
375,287
91.738%
Zinc
18
0.004%
Lead
989
0.242%
Carbon and Mild Steel
73.
Cumlative Metal
Copper
518
0.127%
Aluminium
529
0.129%
Stainless Steel
Stainless Steel
31,719
7.754%
Aluminium
Copper
Lead
Zinc
Other
The study investigated practicable routes in which to
implement each particular scenario. From here these
routes were assessed both quantitatively and Figure 5 - Cumulative and annual LLW arising profile
qualitatively, against a number of metrics; these were
Figure 6 - Pie chart showing the contribution made by the
Cost & Schedule, Security, Safety and Environmental different types of metals to the total LLW metals arising
Impact. Table 2 gives the specific details and costs of over the lifetime of the site
each of the scenarios. A spreadsheet was produced in
conjunction with the report, providing the quantitative argument. Within which all associated reasonable
costs and characteristics are included, for example, capital and operational costs, disposal costs,
decontamination factors. In addition, the spreadsheet has been constructed in such a way that ensures the
study to be an adaptable piece of work, able to evolve as the situation progresses, and thus continue to
provide a basis for strategic thinking.
Table 2 – Summary of the details and indicative cost of each scenario
It should be remembered that the
costs shown in Table 2 are given as
guidance only; they are not a
detailed costing that might be
£1068M
expected to result from a design
study. From a monetary point of
view it can be seen that scenario 2
£1092M
is favoured. This is because both
costly disposal at the LLWR and
£1146M
expensive
additional
treatment
plants are avoided. Having said this,
the variation in cost between the
£1294M
scenarios is marginal. For this
reason other factors have a greater
importance, such as the application of the WMH. It was concluded that it would be both economically and
environmentally beneficial for Sellafield to have an additional LLW decontamination facility. However,
Scenario
Details
1
Current wheelabrator remains
Decontaminate LLW metals to
2a
exempt
where
practicable:
Wheelabrator + Chemical Pickling
Decontaminate LLW metals to
2b
exempt
where
practicable:
Wheelabrator + Electrochemical
All metal waste decontaminated
3b
through to exempt: Wheelabrator
+ Chemical Pickling + Flux Smelt
All metal waste decontaminated
3c
through to exempt: Wheelabrator
+ Electrochemical + Flux Smelt
Costs
£1121M
74.
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Cumulative Volume (m 3)
350,000
12,000
Page 21 of 61
further work is needed to underpin the cost analysis, and thus the business case. The following provides
the key recommendations to come out of the LLW decontamination option study.
•
•
•
Initiate a project to assess the case for taking forward LLW metal decontamination – focussing on
Chemical Pickling and Flux Smelting, but also considering Electro-polishing for more difficult items.
Based on current LTP assumptions the timescale for decisions is relatively short owing to the arising of
several large waste streams (around 10,000 te of metal) around 2020.
Maintain the current site Wheelabrator capability for use in decontaminating LLW metals where
practicable. This is recommended despite when the potential cost of operation of the wheelabrator may
occasionally be marginally higher than the simple cost of direct disposal to the LLWR, and this can be
considered the “cost of going green” i.e. doing the right thing with waste.
Assess the regulatory implications and consider provision of LLW metals temporary storage areas at
Sellafield to enable any decontamination plants to work at an efficient capacity and within a reasonable
plant life, i.e. to smooth the waste arisings profile.
75.
The output of the options study will inform the developing LLW Strategy.
76.
Recommendation 9:
Ensure that equipment re-use is considered when developing decommissioning plans
77.
Progress Made:
This recommendation was included during discussions within the Decommissioning Mandate process.
Although it is noted that this strategic opportunity requires more detailed consideration during scheduling
and project planning of decommissioning operations. It is recommended that further discussion and
influencing of the Decommissioning Strategy and Decommissioning OU is needed, together with a wider
consideration of potential reuse of plant & equipment during decommissioning, such as temporary overbuildings, Poly Vinyl Chloride (PVC), Personal Protective Equipment (PPE), etc. The site currently uses
the internal intranet for a ‘sharing scheme’ for reusing equipment from decommissioned or redundant
buildings.
This recommendation will be pursued as and when there is further development of the Decommissioning
Mandates and the Decommissioning Strategy.
78.
Recommendation 10:
Investigate the options for re-use of waste and materials rendered from decommissioning and
demolition
79.
Progress Made:
This recommendation has been progressed mainly by the two IWS Option Studies (one on Reuse /
Recycle of HVVLLW, and one on Decontamination of Bulk Metals). These option studies are discussed in
more detail in the sections for Recommendation 4 and 8 above, but it is worth noting that they considered
the potential reuse of waste & materials from decommissioning and demolition.
80.
The revised decommissioning estimation process also considers potential reuse of materials, and the
developing LLW Strategy discussed the potential reuse of waste and materials during the recent
stakeholder engagement workshops, the output of which can be found at
http://sellafieldsites.co.uk/page/corporate-responsibility/stakeholder-engagement/consultations
81.
The development of the Sellafield IWS, which encompasses and integrates all the past, present and future
wastes at Sellafield, both radioactive and non-radioactive, is a long term project and will take several years
to complete.
82.
Engaging with stakeholders is an important aspect in the development of the Sellafield IWS as it enables
us to discuss key findings and obtain the stakeholders views. The output from these engagements informs
the development of future versions of the Sellafield IWS. Version 2 of the IWS was presented to
Stakeholders in June 2007. It was noted during the engagement that identification of stakeholders and
matching the communications to their needs is very important for going forward.
83.
Sellafield Ltd fully appreciate that stakeholder engagement is a two-way process and can be initiated by
either one or more of our stakeholders or by Sellafield Ltd. We always endeavour to be as responsive and
flexible as possible to our stakeholder’s requirements. Stakeholders who wish to initiate engagement with
us to more fully develop the Sellafield IWS would be welcome.
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2.2
Progress against the 2007 IWS (Version 2) Action Plan
84.
The recommendations from the 2007 IWS (Version 2) were developed into an action plan to ensure the
recommendations were addressed in a suitable time-frame. The table below shows the action plan
together with a summary of the outputs of the actions taken.
Table 3 - IWS Version 2 Action Plan showing completion of actions
Area
IWS Improvement
Plan (requirement of
NDA PBI S00307/08-35-15 and
RSA 93 schedule 9
requirement)
Define key
performance metrics
(RSA 93 schedule 9
requirement)
Identify and agree
(with NDA) 2 specific
areas to target
improved
understanding. To
inform improved
understanding within
IWS Version 3
Findings of Version 2
to inform 2008 LTP
Learning from
experience (LFE)
from ongoing
decommissioning
projects
Key
recommendations
made in IWS Version
2 Section 7
Action Plan
Produce an IWS ‘improvement programme’,
addressing the improvement of the IWS for
Version 3 and beyond to manage the risks and
opportunities identified in Version 2.
The ‘cost benefit matrix’ will be used to assign the
priority and benefit/timing assessment in
conjunction with affordability will provide the
schedule input.
Produce interim metrics
Produce metrics
Timescale
End August 2007
Conduct options studies for these two specific areas:
HVLA
Decontamination options
Summary report of
interim status – end
March 2008
Options studies by
end June 2008
Demonstrate:
Changes to waste strategy between submission
of IWS Version 2 and the 2008 LTP submission
Any additional waste strategy risks and
opportunities identified between submission of
IWS Version 2 and the 2008 LTP submission
Actions the site intends to pursue under 2008 LTP
to improve future versions of the IWS and to
manage the risks and opportunities identified in
IWS Version 2.
Develop a process for capturing and exploiting
LFE from ongoing decommissioning projects.
Use this information to improve definition of
approaches, define characterisation techniques
and methodologies as key enablers to future
application of the WMH.
Demonstrate progress in refining estimates of
volumes
of
wastes
generated
from
decommissioning.
The recommendations in Section 7.1 will be
assessed for 2008 LTP implementation, following
the process established for LTP production
Implementation of these recommendations in line
with the timescales agreed in the LTP
March 2008
COMPLETED –
Document produced
(GEN-2097A) issued to
st
the NDA on 31 March
2008
March 2008
COMPLETED – Data
Quality Objectives
(DQO) Process &
Database developed and
demonstrated to the
NDA as part of PBI
(GEN-2098A).
September 2007
COMPLETED as
priorities / resources /
commercial constraints
have allowed – See
Section 2.1
Sept 2007
May 2008
Action Taken
COMPLETED – GEN1945A
COMPLETED – Key
Performance Indicators
(KPIs) defined and
agreed with the NDA to
revised timetable.
Provided to the NDA on
th
30 June 2008
COMPLETED – See
Section 2.1of this report.
Options studies
produced. Issued to the
st
NDA on 31 March 2008
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Area
IWSSG review of
IWS further
opportunities
Action Plan
Conduct a workshop to identify opportunities that
could
be
created
by potential
radical
concepts/change in policy direction.
Workshop to comprise of membership of IWSSG
plus other key individuals as appropriate
Output to inform future iterations of IWS
Timescale
October 2007
End June 2008
Non-radioactive
wastes within IWS
Improve definition of non-rad dataset for IWS
Version 3.
End June 2008
Behavioural changes
to support
implementation of
recommendations
Confirm the correct cultural changes required
(e.g. target setting, Sellafield Site Procedures
(SSPs), awareness training)
Identify and initiate means of affecting these
behavioural changes
Communicate findings of IWS within internal
‘stakeholder
community’.
Utilise
existing
communications routes and target plants and
projects most affected.
Via existing mechanisms obtain regulator and
internal stakeholder buy-in (note may require
some changes in established positions e.g.
interim inert raw waste storage)
End
December
2007
End June 2008
3.0
End October 2007
Action Taken
IWSSG Minutes from
th
meeting on 20 August
2007. Originally planning
this for October 2007,
however, the IWSSG
considered it appropriate
to delay this workshop
until sufficient
management attention
can be devoted to it,
once the site priorities
are resolved – likely to
be circa April 2009
NO PROGRESS - due to
funding & resource
limitations - Refer to
Section 4.5
ONGOING
A series of internal
communications on the
IWS have taken place.
Strategic Developments impacting on IWS
85.
There have been several other developments at Sellafield since the IWS V2 was issued in June 2007
which together with some external influences, impact upon the overall site strategic development and the
IWS. These are discussed in the sections below.
86.
Funding
As already mentioned, the funding on the site means that the current LTP developed for operating and
decommissioning the Sellafield site is not presently fully funded and hence cannot be progressed as
planned. The scope and schedule of the LTP is being reassessed. If the schedule for retrievals and
decommissioning has to be extended there will be an increased overall cost for decommissioning the
Sellafield site owing to extended operating lifetimes for plants and infrastructure and the stop-start nature
of decommissioning operations that will be engendered. The site is currently reassessing the strategy
against available funds, which will be used to inform future LTPs. The site has developed a list of site
priorities based on the NDA Prioritisation Index, and hence the shortfall in funding means that lower priority
work will be rescheduled in favour of progressing higher priority work. In addition to funding it is becoming
apparent that the workload facing the site is placing considerable demand on scarce resources across the
UK. This also needs to be taken into account when scheduling project work and work done to implement
the IWS.
87.
UK Discharge Strategy Review by DEFRA
The ongoing Department for Environment, Food and Rural Affairs (DEFRA) review of the UK Discharge
Strategy may have an impact upon the Sellafield site and hence upon the Sellafield IWS. The review is
currently issued for consultation. Hence assessment of any impact this may have on this document is not
possible at this time.
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88.
2008 LTP
The development and delivery of the 2008 LTP for Sellafield was subject to a number of major changes
and challenges. The impact of these, and completion of a jointly agreed Strategic Review with the NDA,
resulted in a delay to the commencement of the production of the plan. Despite the challenging timescales,
the 2008 LTP was presented in March 2008 to the Sellafield Executive for review and approval. As the
plan did not reflect further advised strategic changes the Executive concluded it would be premature for
Sellafield Ltd to endorse the 2008 LTP. The plan however will help to serve as the Control Baseline for
2008/09, providing a governance and performance reporting framework. A copy of the unapproved plan
has been delivered to the NDA for information. Work is now underway to produce a way forward that
addresses the requirements of the Regulators, the NDA and the SLC (Sellafield Ltd). Whilst this work is
ongoing the gaps and issues identified in the current plan will be addressed and the LTP updated
accordingly. Updating of the plan will be managed via the Master Project List using a Real Time LTP
process.
89.
National LLW Strategy
The NDA has recently begun development of a national LLW strategy. Sellafield Ltd is therefore producing
the Sellafield LLW Strategy for January 2009 that will help inform the developing national strategy. This is
discussed in greater detail in a later section of this report (section 4.1.4 – LLW Strategy)
3.1
Other Strategic developments in the Sellafield Lifetime Plan (2008)
90.
Reprocessing Timelines
There are a number of strategic changes in 2008 LTP that have arisen due to factors other than the IWS,
and some of these will impact upon the IWS. The most significant are the decisions to extend the
operational period of both Thorp and Magnox reprocessing. Figure 7 displays the situation
diagrammatically, highlighting the two main contributing factors, and also the key aspects of the site that
are affected as a result.
Figure 7 – Knock-on effect of extended Thorp and Magnox operational periods
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High Level Waste Plants (HLWP) evaporative capacity impact on THORP strategy
91.
It was assumed in the 2007 version of the IWS (Version 2) that Thorp would be operational at the rate
programmed in 2008 LTP. The assessed date when HA Evaporator (Evaporator D) will be available for
processing HA liquors is likely to limit Thorp throughput. This has a significant impact on the site strategies
as it extends the operational life of Thorp and subsequent downstream facilities.
Legacy Ponds & Legacy Silos
92.
The Legacy Ponds & Legacy Silos (LP&LS) strategy remains unchanged apart from some tactical aspects
of the strategy implementation that have affected the delivery timescales of key projects, as shown below:
Figure 8 – Legacy Ponds & Legacy Silos Schedule
93.
Figure 8 shows the schedule for the various plants that make up LP & LS. These are the revised dates
since the publication of Version 2. The ponds and silos have had their retrievals schedules extended by 13 years. Those plants without an extension noted on the graphic are the treatment plants that will process
the waste. It follows that they are also pushed back by a similar timescale. Site Ion Exchange Plant
(SIXEP) waste processing is in the early stages of design, however it can be assumed to be operational in
line with SIXEP waste retrieval dates.
94.
Owing to the changes in funding and regulatory constraints, this change in programme scheduling is a
good example of how the IWS strategic process is applied, i.e. strategy conception, deployment, tactics
and finally flankguarding the strategy to changes, in this case funding. This process is referred to earlier in
this report, within Figure 8. This also demonstrates good strategic governance, such that as the changes in
funding and regulatory constraints were assessed and the consequential modifications were
communicated using the strategic governance arrangements on the site.
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3.2
Strategic Governance Arrangements
95.
In producing the IWS for Sellafield it was recognised that the arrangements for strategic governance of the
site included elements of duplication. The Strategic Authority at Sellafield undertook to review and revise
the arrangements. In addition, the NDA included a performance incentive (PBI element 2 PAF S003-07/0835-15) for the improvement of this issue to be delivered alongside the IWS.
96.
This section provides a summary of the restructured governance arrangements for the Sellafield site.
97.
The NDA are reviewing their arrangements for acting as the strategic mind. Therefore, the strategic
governance arrangements summarised in this section should be considered as ‘interim arrangements’
whilst the NDA further develop their arrangements for the ‘strategic mind’ and until the transition to the new
PBO is complete.
98.
In the most part, the previous arrangements have been largely successful, however a number of recent
changes have challenged the adequacy of the previous format of strategic governance. These changes
come from three sources; firstly, the desire of the NDA to strengthen its role as the strategic mind.
Secondly, a mismatch between funding, resources, and the schedule of work required to be done over the
next three years, and finally, the recent production of the 7 Point Plan business strategy and the need for it
to be aligned with the technical and engineering strategy. For these reasons the strategic governance
arrangements were revised. A number of options were considered and the preferred option that was taken
was to enhance existing arrangements. Table 4 provides a summary of the new strategic governance
arrangements.
Table 4 – Current Strategic Governance Arrangements
Enhance Existing Arrangements
Structure
Integrated Waste
Strategy
Board of
Executives
(Strategy
Steering
Groups)
Nuclear Decommissioning Production
& Major Projects Group Operations
Pros
-
Cons
-
Notes
-
-
99.
7 Point
Plan
Infrastructure
Builds on existing strengths
Integrates business and technical strategies
Allows the executive to concentrate on only the most
important issues
Retains detailed knowledge
puts higher workload on the executive to understand
and make strategic decisions
Duplicates resources
Executive have a more active role in directing
business, technical and engineering strategies. It does
not allow decisions to be taken outside these forums
IWS remains unchanged with any outputs being fed to
the Executive strategy group.
To ensure strategic governance is coherent across the site, members of the Strategy & Transition Group,
of which the IWS team is a part, sit on or chair these various Strategy Steering Groups.
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3.3
Contaminated Land & Site End States
100.
The physical condition of the site at the point when the NDA has finished its business is termed the ‘End
State’ and the use to which the land is put is termed the ‘End Use’. The West Cumbria Site Stakeholder
Group (WCSSG) considered the future of the site, including end state options in 2007 on behalf of the
NDA, with the outcome that the preferred end use was continuing industrial and commercial reuse
including research. This was influenced by the strong desire for continued significant employment in the
local area. There was recognition from the stakeholders that part of the site may remain under long-term
institutional control but also an aspiration from the NDA that as much of an “Outer Zone” as possible on the
site would be de-licensed. The WCSSG considered this work to be a first stage in an iterative consultation
process and expect to be involved in the future evolution of end states.
101.
The base case assumption for contaminated land management in the Sellafield 2006 LTP (subject to
regulator approval/agreement and demonstration that it was the best practicable environmental option)
was that ILW would be excavated and treated to reduce its volume. One proposed means for achieving
this would be to concentrate the contaminated fraction of soil in a “soil washing” process, and thus dispose
of the contaminant to a national ILW repository. Material that was LLW with activity greater than 37 Bq/g
would be disposed of in a near surface disposal facility at Sellafield. Material that was VLLW would be left
in place unless excavation was required to gain access to LLW contaminated soil. A programme of local
groundwater management would be implemented during the excavation phase to enable excavation of
ground from below the current groundwater table. Key assumptions that underpinned the strategy were
that:
• disposal routes would be available for all the wastes
• it would be possible to remove ILW soil from beneath residual building foundations
• it would be possible to reduce the volume of ILW by a treatment process
• stakeholders, including regulators, would allow VLLW soil to remain in-situ and naturally decay
• the site would be under indefinite institutional control and that de-licensing would not be required
102.
The 2006 LTP assumed that contaminated ground and groundwater would remain in-situ until 2050 while
the Separation Area (the main legacy & nuclear reprocessing zone of site) was being cleared of buildings
and facilities, and that remediation would take place between 2050 and 2120. Activities associated with the
base case strategy were primarily associated with the restoration phase of the Sellafield site post 2040 and
did not identify the need for any interim containment or stabilisation measures to prevent the further spread
of contamination prior to completion of decommissioning activities.
103.
Since the formation of the new Sellafield Contaminated Land Team this strategy has been under a process
of review and the 2007 LTP for contaminated land identified the following key objectives:
• Development and implementation of a strategy to manage historical burial trenches in the Separation
Area 2008 – 2018. (This is the largest source of radioactivity in the ground)
• Management control of existing groundwater contamination 2011 – 2050
• Treatment of existing sources of radioactivity in the ground 2020 – 2050
• Remediation of near surface contaminated ground near or beneath buildings incorporated into the
demolition activity (2009 – 2050)
104.
These topics are being worked on further, involving regular discussions with the regulators and NDA. The
baseline approach now being envisaged is as follows:
• Site Characterisation, 2008 -2009
• Assess data, model potential scenarios and carry out BPEO/BPM studies with stakeholder involvement
2010 – 2015
• Institute a groundwater management “line” around the Separation Area, 2015 – 2020
• Remediate contaminated areas around site as they become available, 2020 – 2040
• Remediate Separation Area in Zones between 2040 – 2070
• Consider opportunities to de-license / redevelop / landscape selected areas of the site
• Ongoing management of the residual areas, possibly involving waste disposal activities
105.
Key elements of the contaminated land strategy are to use the new characterisation data to develop risk
based remedial approaches in conjunction with stakeholder and regulatory interaction and to optimise
sustainability by effective sorting and segregation of contaminated soil and management of contaminated
groundwater in order to maintain control and minimise waste.
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106.
The volumes of contaminated land (as currently assessed) remain the same as provided for the 2007 UK
Radioactive Waste Inventory, with the assessment providing a range of volumes. Summarised here are
the ‘most likely’ volumes of contaminated soil at Sellafield:
3
•
ILW Soil, approximately 1,600m
3
•
LLW Soil, approximately 1,000,000m
3
•
HVVLLW Soil, approximately 13,500,000m
3.4
Integration with Windscale
107.
The integration of the Windscale SLC within the Sellafield Ltd SLC took place on 1st April 2008. The NDA
and the Environment Agency (EA) recognise that it may take some time to integrate the two sites IWSs;
hence for 2008 the two sites IWS reports will be submitted separately. The EA has included within the
Compilation of Environment Agency Requirements (CEAR) a requirement for a combined IWS by the end
of June 2009.
108.
In advance of this, work is being progressed within the financial year 2008/09 to share information and
identify opportunities as follows:
identify reciprocal opportunities for ILW treatment routes within planned and existing facilities
identify and incorporate the relevant data into Sellafield’s Overall Effluent Strategy Model (OESM) for
the gaseous and aqueous effluents from the Windscale site
sharing 'best practice' between IWS teams following feedback from the NDA review process recently
completed by Nexia Solutions
109.
This work will form a strong basis for a combined IWS by the end of June 2009.
4.0
Progress Made on Waste Management Strategies
110.
The purpose of this section is to report on how different component waste strategies have progressed
since the publication of IWS Version 2 in June 2007. The various strategic advances are discussed in
terms of the progress made. The aim of which is to provide the reader with an update of the different waste
strategies on site, whilst also demonstrating how the principles behind the IWS, such as the waste
management hierarchy, are applied.
111.
This section should be read in the knowledge of the current funding constraints. The development of most
strategic significance for the Sellafield site has been the funding gap. This is the difference between the
amount of money Sellafield Ltd will receive from the NDA and the scope of work that was originally
planned. As a result a review has taken place and a number of projects have been reprioritised or
deferred. The key strategic priority of the site remains focussed on the reduction of the most significant
hazards. These are as follows:
Reduce Highly Active Liquor (HAL) stocks
Retrieve and immobilise Magnox Swarf Silo waste
Retrieve and immobilise First Generation Magnox Storage Pond waste
Reprocess stocks of wetted Magnox fuel to ensure that fresh Magnox fuel is not allowed to degrade
Improve the containment of plutonium residues
Reduce the hazard potential of the Floc Storage tanks
Retrieve PCM to modern stores
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112.
The format taken for this section is that the different strategies are discussed relevant to their waste form,
in that the sub-categories are Solid, Aqueous and Gaseous Wastes. Prior to this, the WMH is explained,
and why the Sellafield interpretation varies from the conventional framework.
Origin of the Sellafield version of the Waste Management Hierarchy:
SAFETY AND RISK REDUCTION
AVOID
Figure 9
Figure 10
MINIMISE
REDUCE
RE-USE
RECYCLE
ENERGY RECOVER
ABATE
DISPOSE
Figure 9 – ‘Conventional’ waste management hierarchy
Figure 10 - Sellafield Ltd adjusted version of the Waste Management Hierarchy
113.
The WMH is a framework used to inform strategic thinking, highlighting the order in which options for
dealing with waste should be considered. The WMH is applied throughout industry, and is not limited to the
nuclear sector. The initial aim of the hierarchy was to provide a way of thinking that would extract the
maximum possible benefits from products, whilst generating the minimum amount of wastes. Figure 9 is
an example of a WMH that would be applied to municipal, non-nuclear, waste management. Figure 10
shows how the WMH has been adjusted to better suit the needs and challenges faced at Sellafield site. As
with the traditional model, those at the top of the triangle, shown in green are the factors of most
importance, demanding greatest consideration and giving the greatest benefit, and as you progress further
down the triangle the options for waste management become less favourable. The primary difference has
been the inclusion of ‘safety and risk reduction’, at the very top of the triangle. This is considered the most
important priority at Sellafield, such that if a strategic option is chosen which is not necessarily the best
from a waste minimisation viewpoint but which provides essential safety & risk reduction, then that
strategic option would be considered the ‘right thing to do’. The second difference is the segment that
reads ‘Abate’. Prior to waste being discharged into the environment, any opportunity for abatement should
be explored. This is predominantly applicable for the treatment of gaseous and aqueous wastes, thus
reducing the impact to the environment upon final discharge. Finally, the nature of the Sellafield site
inevitably means that a lot of the waste already exists. In such instances the application of the WMH
generally focuses on the lower levels of the triangle and on avoiding the unnecessary creation of
secondary waste.
4.1 Solid Wastes
4.1.1 Update to the solid radioactive waste strategy
114.
The strategy for radioactive solid wastes in this version of the IWS (Version 2) is based on the 2008 LTP
strategy for Sellafield. This includes the following changes from the previous (2007 LTP) baseline:
Extended Magnox and Thorp reprocessing programmes due to constraints of the HA evaporator
capability and the reprocessing strategy for Magnox, overseas & UK Advanced Gas-Cooled Reactor
(AGR) fuel. The end of Thorp reprocessing has been extended to 2014/15 (an extension of 3 to 4
years) and Magnox reprocessing to 2015/16 (an extension of 3 to 4 years). The revised end date for
HALES (Highly Active Liquor Evaporation and Storage) is now 2024/25 (an extension of 1 to 2 years).
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There are no major changes from the previous 2007 LTP baseline for LP&LS strategy. Some 2007
LTP opportunities have however progressed into the current 2008 LTP baseline such as processing
wet bay ILW from the First Generation Magnox Storage Pond in the Waste Encapsulation Plant
(WEP). Further opportunities for LP&LS wastes are currently being developed and will be reviewed
through the sites ILW governance process. The high level plan is to retrieve historic wastes from the
current storage facilities, immobilise the waste and provide interim storage pending final disposal. The
3
portfolio comprises of approximately 18,000 m of historic waste, which will be immobilised into 24,000
stillages/packages. Handover of the legacy facilities to decommissioning is planned to commence
around 2020 and will be completed by 2035. Store operations will be required up until 2070.
While there is a desire to accelerate progress, opportunities to reduce the total cost also need to be
taken into consideration. The drivers for LP&LS, developed to reflect these concerns are:
• Deliver safe, secure and environmentally responsible accelerated hazard reduction
• Care for, restore and enhance current assets to allow the ongoing safe storage of the existing
inventory so that risks from the inventory are as low as reasonably practicable.
• Minimise the creation of new liabilities by making the best use of existing site assets.
• In order to achieve risk reduction through the early retrieval and processing of bulk waste and fuel
debris the emphasis will be to favour proven, mature technology. However, innovative solutions
that are being, or could be, researched and developed to such an extent that they can be expected
with confidence to be available within the appropriate period will be considered where these might
offer early risk reduction benefits.
• Ensure that BPEO process is used to inform the current and future strategy.
The strategy for LLW has been revised since the previous 2007 LTP baseline and now includes a suite
of new-build treatment facilities (subject to BPEO) so as to minimise overall volumes for disposal to the
LLWR and successor facility. These treatment facilities are assumed to commence active operations
in 2020 and current arrangements such as High Force Compaction of compactable LLW through
WAMAC is expected to continue until this date. After 2020, capability will be available for thermal
treatment, melt / smelt and low force compaction. Mechanical decontamination of metals via the site
wheelabrator is expected to continue, as is the practice of emplacing any non-compactable (and nonprocessable) LLW into International Standards Organisation (ISO) freight containers for grouting at the
LLWR or successor facility.
The PCM strategy has been revised since 2007 LTP. The strategy now includes a new build treatment
complex to process PCM waste that is not compliant with the current compaction facility (WTC1a). The
complex is to commence active operations in 2018 and will include the capability to re-work any PCM
that is not suitable for disposal to the repository. Assumptions have also been updated since 2007 LTP
and an increased working pattern and throughput rate through WTC1a is assumed in order to
contribute towards meeting Nuclear Installations Inspectorate (NII) Licence instrument 326(b).
The strategy for the Final Treatment and Disposal of ILW OU has been revised since the previous
(2007 LTP) baseline. 2007 LTP assumed mobile facilities for conditioning decommissioning wastes
and this concept has now been replaced with facilities that are fixed as there is insufficient industry
experience on mobile technology for βγ (beta & gamma) contaminated ILW. The strategy also
includes a dedicated facility for inspection, assay and re-work of ILW prior to final disposal. The export
of all ILW to the repository including PCM is to remain in the scope of this OU although the rework of
PCM is now included in the PCM strategy.
There has been no significant change to the VLLW strategy for the site. The lifetime projected volume
of VLLW has increased by approximately 22% due to the output from some of the recent
decommissioning mandates and bulking factors that were not included in the 2007 LTP assessments.
The CLESA is only anticipated to have a 15-20 year lifetime and available capacity and therefore a
new facility will be required. This may require new land acquisition and will certainly require planning
applications and EA approval. The options for the treatment of High Volume VLLW so as to minimise
disposal requirements are included in the IWS option study referred to in Section 2.1, paragraph 42 of
this report.
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115.
Table 5 illustrates the total lifetime quantity of radioactive wastes requiring disposal from Sellafield and
Calder Hall, including reconciliation against the previous baseline.
Table 5 – Total lifetime projection of packaged waste from Sellafield (excluding LLW and VLLW
contaminated land)
Waste
2007 LTP
2008 LTP
Explanation for the
Category
packaged
packaged
difference
3
3
volume (m )
volume (m )
1,565 m3 = 8,070 1,464 m3 = 7,545 Reduction
HLW
in
AGR
fuel
HLW containers
HLW containers
reprocessed due to the shut
*excludes returns *excludes returns down of Thorp as well a
to
overseas to
overseas reduction in HLW projected
customers
customers
from POCO
3
279,450 m3
218,644 m
ILW
Decommissioning
arisings
3
3
= 63,375 3m box = 81,000 3m box have increased due to the
(inc.
equivalents
equivalents
output from some of the
PCM)
completed mandates as well as
revised loading assumptions
3
for 3m boxes.
3
3
830,817 m
755,566 m
LLW
Although raw waste quantities
= 42,606 HHISOs = 38,747 HHISOs have increased due to the
output from decommissioning
mandates, overall packaged
volumes have reduced due to
the impact of the new LLW
treatment processes assumed
in 2008 LTP
3
3
1,153,000 m
1,407,767 m
Raw waste quantities have
VLLW
(Raw waste)
(Raw waste)
increased
from
decommissioning due to the
output from the completed
decommissioning
mandates
and bulking factors that were
not included in 2007 LTP
assessments.
116.
It should be noted that the Waste Accountancy Templates required by the NDA have superseded the
waste inventory information previously provided in the June 2007 IWS (Version 2).
4.1.2 High Level Waste (HLW) strategy
117.
The HLW strategy has been updated since the previous issue of the IWS (June 2007) and reflects the
extended Magnox and Thorp reprocessing programmes. New build is required for additional HA
evaporator capacity, replacement Highly Active Storage Tanks (HASTs) and a replacement Vitrified
Product Store (VPS).
118.
The extended outage of Thorp as a result of the feed clarification cell event has impacted on the NII’s
position on HAL stocks. The headroom between the current inventory and the NII limit is greater than
envisaged at the time the specification was issued and consequently the NII have changed the shape of
the specification as part of its biennial review in 2007.
119.
The total allowable stocks of HAL are to be progressively reduced until July 2015 when the stock of HAL is
3
less than 200m . Reductions are to be achieved through management of reprocessing and vitrification
schedules. Figure 11 illustrates the predicted levels of HAL stocks compare with the limits as established
with the NII, shown by the teal coloured trace. It can be seen that the total volume within the HAST tanks is
always below the agreed limit. Key assumptions within Figure 11 include the routing of fresh HAL arisings
to replacements HASTs from 2013, throughputs between 300-400 containers per annum through Waste
Vitrification Plant (WVP) for the remainder of the vitrification programme and no inclusion of wash liquors.
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Figure 11 - Levels of acceptable HAL stocks as agreed with the NII
Graph comparing volume of Highly Active Liquor (HAL) with the NII agreed limit for HAL stocks
1400
1200
Volume (m3)
1000
800
600
400
200
0
Apr-2008
Apr-2009
Buffer Volume
120.
Apr-2010
Apr-2011
HAST Tanks No. 9-21
Apr-2012
Total HAST Tanks
Apr-2013
Total HAL Limit
Apr-2014
Apr-2015
Total HAST inc. wash water
The strategy associated with the lifespan of the HLW evaporators (A, B, C, D and E) have been revised
since the previous 2007 LTP baseline as follows:
Evaporator A: To support WVP returns only, until 2020
Evaporator B: To support 90% Magnox operations until Financial Year (FY) 2010/11 and then remain
available as a contingency until 2012/13
Evaporator C: To support 10% Magnox and 100% Thorp operations until FY 2010/11 and then remain
available as a contingency until 2013/14
Evaporator D (new build) : To support all Magnox and Thorp operations and POCO from 2010/11 and
remain available as a contingency until 2022/23
Evaporator E (new build): To support WVP effluent arisings from 2010/11 and POCO of the HASTs
until 2024/25
It should be noted for Evaporators D & E that these timescales are under review by ourselves, the NDA,
and the project contractors - taking into account the capability within the UK and worldwide to deliver such
major engineering projects. Extending these timescales has a significant impact on extending the
operational life and delaying the decommissioning programmes of the HLWPs and downstream plants and
infrastructure.
121.
Provision has been made in 2008 LTP for additional HAST capacity due to risks associated with the long
term capability of the current HAST fleet to support ongoing reprocessing, WVP operations and POCO.
The issues are primarily due to corrosion of cooling components and there is ongoing work to establish the
full mitigation of this as well as final HAST capacity requirements.
122.
The Residue Export Facility (REF) is undergoing commissioning after recent modifications. The aim is to
enable Vitrified Residue (VR) to be returned to overseas customers. The facility will enable the VR
containers in the Vitrified Product Store (VPS) to be de-stored, checked for customer acceptability and
then loaded into export flasks. Exports are assumed to commence this year in Financial Year 2008/09 and
are scheduled to be completed by end of 2015/16. A total of 1,787 containers are assumed to be exported.
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123.
An additional Vitrified Product Store (VPS2) has been included in 2008 LTP due to the 50 year design life
constraint on the existing VPS (VPS1). VPS 1 is expected to reach its design life-limit by 2040 and VPS 2
will therefore ensure sufficient capability to safely store vitrified containers until the availability of the
repository, currently assumed to be 2075. Export of vitrified containers to the repository is expected to be
completed by 2095 as illustrated Figure 12:
VPS (WVP Containers Stored profile)
VPS Capacity (7960)
8000
7000
Number of Containers Stored
WVP Containers
6000
5000
4000
3000
2000
1000
Mar 2099
Mar 2096
Mar 2093
Mar 2090
Mar 2087
Mar 2084
Mar 2081
Mar 2078
Mar 2075
Mar 2072
Mar 2069
Mar 2066
Mar 2063
Mar 2060
Mar 2057
Mar 2054
Mar 2051
Mar 2048
Mar 2045
Mar 2042
Mar 2039
Mar 2036
Mar 2033
Mar 2030
Mar 2027
Mar 2024
Mar 2021
Mar 2018
Mar 2015
Mar 2012
Mar 2009
0
FY Ending
Figure 12 - WVP containers requiring storage and disposal - minus exports to overseas customers
4.1.3 Intermediate-Level Waste Strategy Update
4.1.3.1
Operational wastes
124.
The Magnox and Thorp reprocessing programmes have been extended which has resulted in an increase
to the operating timescales for the supporting ILW conditioning facilities, namely Magnox Encapsulation
Plant (MEP) and Waste Encapsulation Plant (WEP). The Waste Packaging and Encapsulation Plant
(WPEP) will also continue to support reprocessing and remediation activities.
125.
MEP will continue to support Magnox decanning operations and POCO until 2019/20. Once Magnox
reprocessing has been completed, there are potential opportunities for utilising MEP to condition other ILW
such as Tokai Mura End Crops, Magnox Silo scrap and some βγ contaminated ILW from
decommissioning. These opportunities are to be reviewed through the ILW site governance processes.
126.
WEP will continue to support Thorp reprocessing which is currently scheduled until 2014/15. It will also
condition Magnox Ponds Wet bay miscellaneous solid wastes from 2010 onwards and is likely to continue
to do so until the availability of the Box Encapsulation Plant (BEP), currently planned to become
operational in 2015. There is also an opportunity to utilise WEP for other ILW waste and these
opportunities are to be reviewed through the site ILW governance processes.
127.
WPEP will continue to support reprocessing of bulk feeds from Thorp and Magnox and condition active
flocculates generated from the EARP. The baseline now includes the diversion of SETP feeds to EARP
subject to continuing technical underpinning. Further opportunities for utilising WPEP are to be reviewed
through the site ILW governance processes.
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4.1.3.2
Legacy Ponds and Legacy Silo wastes
128.
The overall strategy for LP&LS has not changed significantly from 2007 LTP. The primary driver for the
LP&LS areas is still the early hazard and environmental risk reduction for the facilities and commitment to
meet the licence specifications issued by the NII on 04 August 2000.
129.
The treatment facilities planned within the LP&LS strategy are as follows:
Silos Direct Encapsulation Plant (SDP) - For the conditioning of ILW from Magnox Swarf Storage
Silos. This facility is assumed to be operational from 2013 to 2027
Sludge Packaging Plant (SPP1) - For the conditioning of ILW sludges from the First Generation
Magnox Storage Pond. This facility is assumed to be operational from 2017 to 2022
Local Sludge Treatment Plant (LSTP) for the conditioning of ILW sludges from the Pile Fuel Storage
Pond. This facility is assumed to be operational from 2015 to 2021
BEP - For the conditioning of ILW solids from the First Generation Magnox Storage Pond and the Pile
Fuel Storage Pond. This facility is assumed to be operational from 2015 to 2024
Pile Fuel Cladding Silo Treatment Plant (PFSTP) - For the conditioning of ILW from the Pile Fuel
Cladding Silo. This facility is assumed to be operational from 2022 to 2026
SIXEP Waste Processing Plant (SWP) - For the conditioning of SIXEP sludges and Sand / Clino. This
facility is assumed to be operational from 2013 to 2019
130.
Conditioned LP&LS ILW packages are to be stored in the suite of new-build Containerised ILW Stores
(CILWS) until 2040 (date given by the NDA for the availability of the ILW repository). The Encapsulated
Product Store 3 (EPS3) is to store some conditioned ILW from SDP prior to CILWS being available.
131.
The potential re-work and export of ILW is included within the LTP Final Disposal and Treatment of ILW
OU and the strategy for this is detailed in the latter part of Section 4.1.3.4 of this report.
4.1.3.3
PCM wastes
132.
The PCM strategy has been revised since the previous baseline to include an additional PCM treatment
complex in order to condition wastes that are not suitable for processing through WTC1a and to assist in
meeting the regulatory specification of NII Licence Instrument 326(b). The new build complex is assumed
to commence active operations in 2018 and will continue operating until the end of PCM arisings, currently
projected to be circa 2060.
133.
Operation of the current PCM treatment facility (WTC1a) is scheduled to continue until 2023 with
progressive enhancements to its throughput deriving from improvement projects and a stage-wise step
change from the 5 day double day working pattern to 7 day double days in 2010 and 7 day 3 shift from
2015 until 2023. This, alongside with the new PCM treatment complex, is assumed to achieve conditioning
of the historic PCM referred to in the NII Licence Instrument, Li326(b), by August 2020.
134.
Raw and conditioned PCM wastes are interim stored in the Engineered Drum Stores (EDS’s). EDS 1 and 2
are operationally full, EDS 3 is operation but its capacity is limited until appropriately designed drum
stillages have been procured to allow optimum use of the storage volume. Modelling work has indicated, a
small store 4 could be required around 2018 based on current Sellafield waste projections. Opportunities
to improve working efficiencies are being explored so that this store will not be required.
135.
The new build PCM treatment complex is to also include the capability to re-work any out of specification
waste products to meet the Repository Waste Acceptance Criteria. The export of PCM product to the
Repository is included in the LTP OU Strategy – Final Treatment and Disposal of ILW.
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4.1.3.4
136.
Final Treatment and Disposal of ILW
The strategy for the Final Treatment and Disposal of ILW includes the following scope:
Treatment and conditioning of βγ ILW from decommissioning, MBGWS contents, AGR dismantler
wastes and excavated contaminated land.
Potential rework of any βγ ILW waste products as required in order to satisfy the Repository Waste
Acceptance Criteria
Vouchsafing and exporting the lifetime yield of βγ ILW and PCM products to the repository
137.
The strategy has been revised to include three new-build ‘fixed’ waste treatment facilities as opposed to
‘mobiles’ which were assumed in the previous baseline. The removal of mobiles as a concept is due to a
lack of evidence in the industry for demonstrating the practicability of large-capacity, mobile ILW treatment
plants – particularly with regards to high dose-rate materials anticipated to arise from Sellafield
decommissioning activities.
138.
There is an opportunity to offset the additional liability of the new treatment facilities by utilising the
remnant life of the existing and future committed ILW treatment facilities (e.g. WEP, BEP, SDP etc). This
opportunity is being explored further and will be reviewed through the site ILW governance process.
139.
A dedicated new-build βγ ILW product inspection and re-work facility has also been included in the
baseline strategy. This facility is scheduled to commence active operations from 2035 (approx. 5 years
prior to repository availability) until the end of Sellafield ILW exports to the repository, currently projected to
be 2108.
140.
The rate at which ILW is to be exported to the repository is currently being reviewed by the NDA as part of
its ongoing National Repository Scheduling exercise. Until this work is finalised, Sellafield has received
guidance from the NDA to assume an export rate of around 1,200 ILW packages per annum for the 2008
LTP. It should be noted that this constraint requires the site to export ILW over a lengthy period of 60 years
and significantly challenges the design lives of the existing stores. Work is currently ongoing to optimise
the store design lives as well as the export rate to the repository.
141.
Figure 13 illustrates the total ILW Export profile from Sellafield to the repository. Key assumptions have
been made in deriving the profile such prioritising the export of ILW from older stores in order to minimise
the impact on the store lifetimes.
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OU35240 - Export Profile to ILW Repository after Rework/ Final Conditioning
1,400
1,200
Ground
Box/Stillage Equivalents
1,000
ILW from Decommissioning.
800
Class 2(A)
EPS3
600
CILWS1
CILWS2
CILWS3
CILWS4
Class 2(A) Ext.
EPS2
EPS1
400
200
AGR Dismantler
Stores
WPEPS
MBGWS
EDS2
EDS3
EDS4
20
40
20
42
20
44
20
46
20
48
20
50
20
52
20
54
20
56
20
58
20
60
20
62
20
64
20
66
20
68
20
70
20
72
20
74
20
76
20
78
20
80
20
82
20
84
20
86
20
88
20
90
20
92
20
94
20
96
20
98
21
00
21
02
21
04
21
06
21
08
0
Financial Year Start
Figure 13 - Export profile of all ILW (including PCM) from Sellafield stores to the Repository
4.1.4 Low Level Waste strategy
142.
The LLW OU is developing the site’s LLW Strategy for issue in January 2009. The strategy will be
informed by the recent series of public workshops that covered such LLW as oils, metals, process waste,
etc.
143.
The LLW strategy, as described in 2007 LTP, has since been updated and now includes a suite of new
build treatment facilities, these are all assumed to commence operations in 2020. The facilities are to
provide a greater degree of volume reduction than that which currently exists on the site and hence will
minimise the overall quantities for disposal to the LLWR or successor facility. The LLW strategy is
summarised below:
Continued use of WAMAC for high force compaction of compactable LLW until 2020
New build thermal treatment capability from 2020 up to the end of site decommissioning, currently
scheduled to be 2113
New build melt / smelt capability for LLW metals from 2020 up to 2113
New build low-force compaction capability for compactable LLW from 2020 up to 2113
Continued use of mechanical decontamination in the form of the wheelabrator for the decontamination
of metals up to 2113
Continued use of direct emplacement of non-compactable items into ISO freight containers
Disposal of LLW to the LLWR until 2050 and to a future LLW disposal facility that has not yet been
specified
144.
Processing assumptions such as the proportion of waste that are suitable for various processes and the
resultant volume reduction achieved are include in the 2008 LTP poster set.
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145.
The total quantity of LLW requiring disposal over the lifetime of the site is illustrated in Figure 14 below. A
comparison is made between the 2008 LTP strategy and the 2007 LTP strategy with the same (2008 LTP)
data-set and it can be seen that the suite of 2008 LTP treatment facilities contribute towards a reduction of
around 19,300 HHISOs. Work is ongoing to understand the range of uncertainty on the waste estimates as
well as the cost and environmental benefit of the new treatment facilities.
70000
2,600
Continue processing as-is
Metal Ingots
Metal unsuitable for melting
Concrete
LTP 07
capability
2,400
60000
2,200
2,000
Overall
reduction of
19,300 HHISO's
Number of HHISO's
1,800
1,600
50000
LTP 08
capability
40000
1,400
1,200
30000
1,000
800
20000
600
400
10000
200
0
20
07
20 /08
11
20 /12
15
20 /16
19
20 /20
23
20 /24
27
20 /28
31
20 /32
35
20 /36
39
20 /40
43
20 /44
47
20 /48
51
20 /52
55
20 /56
59
20 /60
63
20 /64
67
20 /68
71
20 /72
75
20 /76
79
20 /80
83
20 /84
87
20 /88
91
20 /92
95
20 /96
99
21 /00
03
21 /04
07
21 /08
11
21 /12
15
21 /16
19
/2
0
0
Year of Disposal
Figure 14 – 2008 LTP LLW Lifetime Disposal Profile
146.
There are opportunities to further minimise waste volumes such as by increasing the decontamination
capability on the site and appropriate volume reduction of concrete items to increase packing efficiency.
147.
The NDA have instructed the LLWR to develop a strategy for the management and disposal of the nation’s
LLW. The key decisions relating to national LLW matters are made by the NDA and the LLWR. The current
planning assumption used by Sellafield Ltd is for continued availability of the LLWR for accepting LLW
(detailed in Section 4.5.3 of IWS Version 2). Sellafield Ltd also has risk mitigation measures should the
LLWR become unable to accept LLW from Sellafield Ltd.
148.
The NDA initiated a competition process in April 2006 for a new PBO to run the LLWR site, including
ownership of the LLW Repository Limited Company. The new PBO has a broader remit than the previous
operators – it is responsible for the co-ordination of LLW management activities and any potential new
facilities throughout the UK.
149.
In the autumn of 2007 NDA announced that UK Nuclear Waste Management Ltd (UKNWM Ltd) was the
‘Preferred Bidder’ for the LLW Repository contract. UKNWM is a consortium led by Washington Group
International with Studsvik UK, Serco and Areva. The new PBO took over responsibility for the LLW
Repository Site from BNFL on 1st April 2008.
150.
LLW Repository Ltd is working in partnership with the NDA to establish the National Low Level Waste
Strategy Group (LSG) to develop and implement a National LLW Strategy.
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151.
The National LSG has been established to develop a working partnership between the NDA, LLW
Repository Ltd, Regulators, Stakeholders and LLW Consignors to promote innovation, value for money,
and implementation of the waste hierarchy by planning for effective waste disposal solutions. This initiative
will support ongoing nuclear operations, the nuclear site decommissioning and remediation programme
and LLW management needs of ‘non-NDA’ commercial organisations. The National LSG shall serve as a
primary point of contact for integration and engagement on LLW innovations, issues, and strategy
development.
152.
Sellafield Ltd is already anticipating this work and is responding to this National LSG via the current work
towards producing a LLW strategy for the Sellafield site by January 2009. As Sellafield waste is expected
to comprise more than half of all the LLW in the UK, the Sellafield LLW Strategy is likely to form the central
basis of the UK LLW strategy.
4.2 Aqueous Waste Strategy
153.
This section represents the update to the Aqueous Waste Strategy (AWS) as required under Schedule 9
Requirement 1 of the RSA 93 Authorisation within the ‘Compilation of Environment Agency Requirements’.
Historic and Current Aqueous Waste Strategy
154.
To understand the origins of the current AWS for Sellafield site it is necessary to examine the strategy for
liquid effluents developed and implemented in the 1980s. This is summarised below:
“Following the November 1983 beach contamination incident, BNFL made a public commitment
to study what technical options could be employed to reduce low level liquid waste (LLLW)
discharges to the sea. The specific objectives are to reduce the alpha and beta-gamma
discharges to target levels of 0.74 TBq/yr (20 Ci/yr) and 296 TBq/yr (8000 Ci/yr) respectively
and to prevent the discharge of solids and free-phase solvent.
SCOPE
Objectives
Initial scoping work carried out during 1985 was formally reviewed by the Effluent Task Force
during 1986, with a remit to ensure that whilst meeting all the functional requirements, the
scope of work and cost of the proposed development were minimised. The specific objectives to
be achieved are as follows:
(i) To reduce alpha and beta discharges in accordance with the discharge authorisation
requirement that ‘the best practicable means should be used to keep discharges as low as
reasonably practicable’. In this regard, nominal design targets of 0.74 TBq/yr (20 Ci/yr) alpha
and 296 TBq/yr (8000 Ci/yr) beta have been supported by the Radioactive Waste Management
Advisory Committee (RWMAC) and the Department of Environment (DoE).
(ii) To prevent the discharge of free-phase solvents and suspended solids.”
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155.
Since the articulation of the original strategy in the mid to late 80s the plants and infrastructure has now
been built and operated successfully to maturity and generally met or exceeded design intent. This
strategy was developed and deployed by the suite of plants depicted diagrammatically in figure 15 below:
156.
Figure 15 – Sellafield effluent treatment plans 1987
Summary of New Effluent Treatment Plants for the Sellafield Site (1987)
Pond Purges
Site Ion Exchange
Effluent Plant
Low Risk
Effluents
Effluent Treatment
Plant
Sea Tanks 1, 2 & 3
Recycle
Segregated Effluent
Treatment Plant
Medium Active
Concentrates
Sentencing in SETP
Off Spec Pumping
System
Medium Active
Tank Farm
Magnox Spent
Solvent
Thorp Spent
Solvent
Salt Concentrate
Solvent Treatment
Plant
Waste Packaging
Encapsulation Plant
Highly Active Tank
Farm
Recycle
Enhanced Active
Removal Plant
Magnox High
Risk Effluents
Analytical
Services Low
Risk Effluents
Analytical
Services High
Risk Effluents
Sentencing in
EARP
Break Pressure
Tank
SEA
Sentencing in
Analytical Services
Treatment in
Analytical Services
Preliminary
Sentencing in
Analytical Services
Thorp Multielement
Bottle Flushings
Thorp Central
Off-gas
Sentencing in Thorp
Thorp Dissolver
Off-Gas
Effluent Plant
Services Building
Effluent Plant
Maintenance
Facility
Key
Concentrates
Solvent
Low Risk Effluents
High Risk Effluents
Sea Discharges
Solids
157.
Updated descriptions:
Original Diagram by
M Howden
Aug 1987
Drawn by C G Howarth
Figure No A1
This strategy forms the basis by which the site currently manages its effluents and is manifested in the
following tactics:
• Plants and processes will use BPM to minimise the quantity, activity and suspended solids content of
liquid effluent arisings, and to segregate different categories of liquid effluent
• Plants and processes will generally discharge their liquid effluents to centralised treatment facilities,
complying with any receiving plant acceptance criteria
• Centralised effluent treatment plants will continue to be operated as long as technically feasible and
safe to do so. Technical feasibility takes account of economically viable asset care and changes to
effluent feed quality and quantity.
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•
Magnox and AGR fuel pond and Magnox silo effluents are generally discharged to SIXEP for the
removal of Magnox sludge, other suspended solids and soluble caesium and strontium, prior to sea
discharge
HA effluents and low salt medium active effluents are evaporated to minimise volume and immobilised
by vitrification
High salt medium active effluents are evaporated to minimise volume and delay stored to reduce short
lived beta emitters. They are then subjected to floc precipitation and ultrafiltration to reduce activity
prior to sea discharge
High alpha, low active effluents are subjected to floc precipitation and ultrafiltration to reduce activity
prior to sea discharge
Low active acidic effluents are neutralised and blended with low active caustic effluents prior to sea
discharge
Thorp Dissolver Off-Gas scrubber effluent is treated locally by C-14 precipitation and decanting prior to
sea discharge
Thorp pond purge is filtered locally to remove suspended solids prior to sea discharge.
Long lived I-129 is driven to sea as this has been identified as BPEO
•
•
•
•
•
•
•
•
The original strategy is still valid but there have been a small number of improvements in implementation
resulting from subsequent BPM assessments. An example of this is the diversion of Magnox Medium
Active Concentrate (MAC) to the HLWPs for vitrification instead of decay storage and treatment in EARP
prior to discharge to sea. This has significantly reduced the amount of Tc-99 discharged to sea, which
primarily yields socio-economic benefit. It was made practicable by internal segregation of minor,
incompatible components, and by the recommissioning of an existing route. Further improvements may
be identified from ongoing consideration of BPM for current operations and from BPEO/BPM
assessments for facilities at various stages of design
•
It is interesting to compare the original nominal design targets of 0.74 TBq/yr (20 Ci/yr) alpha and 296
TBq/yr (8000 Ci/yr) beta against the discharge authorisation limits of that time. When the new effluent
systems became operational (and looking forward to Thorp being operational), authorised discharge
limits were set at 1 TBq/yr alpha and 400 TBq/yr beta. A significant portion of the total beta limit was to
enable the processing of historic MAC stocks, which has been completed.
Historical & M odel Predicted Discharges - Beta-5 Discharges
Historical & Model Predicted Discharges - Alpha Discharges
250
12000
1970's authorisation
1970's authorisation
10000
Historical Discharges
OES Predicted Discharges
Authorised limit
150
100
Historical Discharges
OES Predicted Discharges
Authorised limit
8000
Activity, TBq
A ctiv ity , TBq
200
6000
1986 MAFF authorisation
4000
1986 MAFF authorisation
1990 MAFF authorisation
1990 MAFF authorisation
50
1994 RSA93 authorisation (unchanged by SALDAR)
2000
2004 revised RSA93 authorisation
1994 RSA93 authorisation (unchanged by
SALDAR and SALDAR2)
09
20
05
07
03
20
20
20
01
99
19
20
95
97
19
91
93
19
19
19
87
89
85
19
19
19
83
81
19
19
77
79
19
73
75
19
19
19
19
07
09
05
Date
20
20
20
01
99
03
20
20
19
95
93
91
89
87
85
97
19
19
19
19
19
19
19
81
79
83
19
19
19
75
73
77
19
19
19
19
71
0
71
0
Date
Figure 16 – Comparison between historical and model predicted discharges
158.
Sellafield operates its current AWS in a manner consistent with the original intent though enhanced with
appropriate tactics, in line with developing regulatory requirements and complying with the discharge
authorisation of the day.
159.
Plants and systems where aqueous wastes are generated, processed or disposed of are managed,
operated and maintained by suitably qualified and experienced persons in accordance with written
processes and procedures. Sellafield Ltd operates under environmental and quality management systems
which are externally validated to appropriate international standards (BS EN ISO 14001: 2004 and
BS EN ISO 9001: 2000).
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This is supported by the findings of a recent comprehensive review by R M Consultants which stated
•
“The outcome of this comprehensive review demonstrates that Sellafield Ltd’s minimisation
practices for airborne, liquid and solid radioactive wastes are mainly consistent with those
recognised as BPM or best practice in comparable national and international situations.
•
The fact that there are only a few areas found for improvement is a good indication of the
efficiency and effectiveness of the overall site waste management system and its integration
across the site.
•
For the Sellafield site, identifying ‘best practice’ for the full range of waste streams is a taxing
task, as many of the processes are specially commissioned operations …Sellafield has
necessarily led the way and can by default be regarded as developing and demonstrating use of
best practice.
•
The exception is for some electrochemical separation technologies including electroflocculation
(used by Atomic Weapons Establishment, (AWE)) and electrochemical ion-exchange (used by
GE Healthcare and United Kingdom Atomic Energy Authority (UKAEA)). These techniques are
not used by Sellafield Ltd due to the large volumes of liquid effluent processed, which would
cause the electrochemical process to be too expensive.”
Future Aqueous Waste Strategy
160.
There are residual uncertainties that will exist as the Sellafield site moves from a well understood
operations role to a decommissioning and clean up role. Decommissioning and clean-up of the site will not
only involve the current operational facilities but also the legacy facilities which contain radioactive wastes
from the early days of civil and military operations at the site. In this period of change it is important that
strategic aspects are managed so as to prevent and minimise future environmental impacts. A number of
facilities will have significantly different challenges during the transition from production to clean up. Whilst
this presents some risks as a result of changing flowsheet there may also be opportunities to re-route
streams, improve environmental performance and reduce costs via employing different tactics to achieve
BPM.
161.
It is worth noting that a contributing factor in determining that the MAC diversion represented BPM was
because it could be implemented via an existing route (which meant costs were not disproportionately
large in relation to the environmental benefits realised). However, even this was not straightforward: as a
result of changing the flowsheet there were knock-on implications for the final solid waste forms which
must always be weighed up in the site’s considerations of the balance of waste forms and Engineered
Destinations (the reader is referred to the 2007 IWS - Version 2 for a more detailed explanation of these
concepts).
162.
In continuing to develop the future AWS for the site, it must be recognised that appropriate use of available
public money requires Sellafield Ltd to prioritise its focus on those areas where the maximum value and
benefit in terms of hazard and environmental risk reduction can be achieved, subject to complying with
legal requirements.
163.
Today significant areas of potential environmental risk are associated with the Magnox Operating Plan
(MOP) and legacy remediation. In the current environment of constrained funding the greatest
environmental benefit will be obtained by investing in these areas i.e. improving MOP timescales and
progressing remediation of high risk facilities, rather than diverting limited funds and key resource towards
the marginal benefits in the area of effluent abatement.
164.
Investment in order to realise marginal benefits can prove to be disproportionate and would be difficult to
justify on BPM grounds. This is particularly so where the implementation time is significant and benefits
can only be realised for a short time. All investment proposals are subject to a rigorous challenge
processes intended to expose the costs and benefits so that an informed decision may be taken by
Sellafield Ltd and NDA as necessary.
165.
Work on the long term approach to effluent management at Sellafield was undertaken as part of the
Overall Effluent Strategy (OES), beginning in 2004. The original aim of the OES was to determine the
optimum processes and chronology for liquid effluent management during the site clean-up programme,
balancing all stakeholder constraints and expectations in compliance with the UK Discharge Strategy. The
OES work was focussed on the timeframe beyond completion of the MOP and the bulk waste retrievals of
LP&LS. The Aqueous Waste Strategy Steering Group was established in 2005 with a remit of governance
on Site effluent management and an initial focus on current effluent issues. The work of the OES team and
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the (now) Aqueous & Gaseous Waste Strategy Steering Group (AGWSG) is consistent, and the output is
embedded into the LTP. Furthermore the modelling and tools that are used cover the full lifetime of the site
and have identified opportunities in both the short and longer term. Decisions on aqueous waste strategy
for the current and medium term are thus taken with reference to the longer term strategy (OES).
166.
The OES work is also relevant to the IWS. Decisions by the IWSSG are taken with due regard to the OES
work. The aqueous waste strategy is focused upon optimising the use of existing facilities, supported by
additional facilities only when required.
167.
The aims of the UK Discharge Strategy are:
• progressive and substantial reduction of radioactive discharges and discharge limits, to achieve the
strategy targets for each sector;
• progressive reduction of human exposure to ionising radiation arising from radioactive discharges, as
a consequence of reductions in discharges, such that a representative member of a critical group of
the general public will be exposed to an estimated mean dose of no more than 0.02 mSv a year from
liquid radioactive discharges to the marine environment made from 2020 onwards;
• progressive reduction of concentrations of radionuclides in the marine environment resulting from
radioactive discharges, such that by 2020 they add close to zero to historic levels. (The terms “close
6
to zero” and “historic levels” are not defined in the OSPAR Strategy and the OSPAR Commission is
continuing to work on establishing agreed definitions.)
Strategic targets for spent fuel reprocessing are stated to be:
•
•
•
•
Reduce the estimated dose to a representative member of the critical group of the general public (i.e.
those persons most exposed to the discharge) to be less than 0.02 millisieverts (mSv) per annum as a
consequence of reductions in discharges to the marine environment from 2020 onwards.
By 2020, total Beta aqueous discharges from reprocessing to be reduced to around 50 TBq/yr Beta 5
(excluding Tritium)
By 2020, total alpha aqueous discharges from reprocessing to be reduced to around 0.2TBq/yr
By 2006, Tc99 aqueous discharge from reprocessing to be reduced to less than 10TBq/yr, and by
2020 to less than 1TBq/yr
168.
To meet these aims, and deliver an optimised strategy regarding aqueous waste, the OES team has
looked to incorporate national and international best practice for effluent management. Alignment of the
OES to the UK Discharge Strategy was achieved in June 2007 and it was predicted future discharges
would be below the current RSA (93) Authorisation site discharge limits.
169.
When treating aqueous streams, an emphasis is placed on abatement as the consideration of applying
BPM to Avoid, Minimise, Reuse & Recycle has already taken place in the selection of process design and
operation of the generating plants. The aim of the abatement step is to transfer the activity from a liquid to
a solid form and contain it for disposal, thus immobilising the activity. It is worth noting that the “Avoid” step
has been assessed by the OES team. They have successfully identified several opportunities to “Avoid”
building new treatment plants and hence avoid adding to the decommissioning legacy through optimising
the use of existing aqueous waste treatment assets such as SIXEP and EARP.
170.
The Sellafield site has recently set in place strategic governance arrangements to develop the site’s AWS
beyond the baseline described in IWS Version 2. The AGWSG was founded in 2005 to provide oversight
of effluent development to ensure it does not compromise the existing baseline strategy and to develop it
further. Using the output of the OES, the IWS, together with OU developments and the site’s response to
the recent EA enforcement notices on particulates, the progress in developing the AWS further has been in
the following 4 main areas.
The Particulate Enforcement Notice served by the EA
The management of aqueous waste that arises from the waste retrievals and treatment programmes
in LP&LS, SIXEP and the historic floc storage tanks.
6
The 1992 OSPAR (Oslo & Paris) Convention is the current instrument guiding international cooperation on the protection
of the marine environment of the North-East Atlantic. It combined and updated the 1972 Oslo Convention on dumping waste
at sea and the 1974 Paris Convention on land-based sources of marine pollution. The work under the convention is managed
by the OSPAR Commission representing the European Community.
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The proposal to switch feeds from SETP to EARP Bulks once volumetric flows decrease following the
end of reprocessing operations.
The developing strategy for managing the future requirement for Low Active Effluent collection,
treatment, and disposal beyond the existing centralised facilities (i.e. after 2040).
171.
These are discussed in more detail in the sections below
4.2.1
Sellafield Ltd’s response to the Particulate Enforcement Notice
172.
In May 2007 the EA issued the Enforcement Notice (EN) No. RS/E NW 000832 to Sellafield Ltd regarding
concerns over the potential for active particulates to be discharged from site and thus enter the
surrounding environment. The basis for this concern is that a number of active particles have been
discovered on beaches local to Sellafield during monitoring programmes. The enforcement notice specified
the following:
173.
1. The Operator shall carry out a best practicable means study into the removal of entrained solids from
radioactive aqueous waste prior to discharge to the environment
174.
2. Implement recommendations identified in 1 above to a schedule and programme agreed in writing with
the Agency or failing agreement, as reasonably specified in writing by the Agency.
175.
In accordance with the specification, Sellafield Ltd prepared and submitted a response report to the
Agency at the end of March 2008, together with a proposed programme of future work. The development
of the forward programme includes the continuation of work that has already commenced and also
captures new work. This work can broadly be categorised into the following:
176.
1. A continued programme of sampling and analysis to inform ongoing and future decisions;
2. Completion of the BPM reviews and any necessary action to address plant specific issues;
3. Ongoing work to address generic site-wide issues including Standards and best practice guides;
4. The development of a specific project looking at solids exclusion from the Sellafield sealine
discharges.
4.2.2
Legacy Ponds & Legacy Silos – SIXEP Contingency Plan
177.
The SIXEP became operational in 1985 and treats the high volume, low specific activity (number of
disintegrations per unit of time), alkaline liquid effluents at Sellafield site. These are generally purge
effluents from fuel cooling ponds. SIXEP filters the effluents to remove solids and subsequently uses ion
exchange technology to target the removal of soluble Cs-137 and Sr-90 prior to monitoring and sea
discharge.
178.
The SIXEP Operating Plan (SixOP) for the period 2007 to 2042 revises and updates the SIXEP Operating
Strategy (SixOS), which was relevant to 2022. It describes the progress that has been made to improve
plant performance and to maintain the plant in a suitable condition to meet future lifetime requirements.
179.
A prime objective of SixOP is to ensure that the Site Executive has an understanding of the complex
issues and uncertainties that exist regarding:
The demand on SIXEP from current and future donor plants e.g. the effects of extended production
and remediation programmes, and the increased challenge from remediation activities particularly of
Sr-90 derived from sludge in the first generation Magnox storage pond.
The capability of SIXEP to provide a high level of service with respect to solid waste storage, plant
longevity and availability.
The environmental impact from the application of BPM improvements to the abatement of discharges
to sea from high volume, low specific activity, alkaline liquid effluents as the site moves progressively
from production operations into its clean-up phase.
The provision of short/medium term and long-term contingency plans in the event of a failure of
SIXEP.
180.
Ensuring that the Site Executive has an understanding of the issues means that a credible strategy can be
endorsement, meeting the requirements of:
The MOP and Nuclear Decommissioning & Major Projects Group (ND&MPG) needs i.e. existing and
future donor plants.
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BPEO and BPM principles.
The provision of contingency measures for the site.
Discharge authorisation compliance.
181.
Development of this plan has included:
Business and stakeholder needs.
Consideration of the current and known potential future feeds.
An assessment of the longevity of SIXEP giving due recognition to the current age and expected
operating life of the plant.
A review of current and future liquid feeds to determine how the challenge can be met in relation to
the existing discharge authorisation.
Tank capacity in relation to the management of the waste solids produced by SIXEP.
A BPEO study to evaluate all strategic options that are available for the management of low specific
activity, high volume, alkaline liquid effluent streams.
A review of asset care and risk management strategies.
A review of plant enhancement and new build projects that were suggested in SixOS.
Establishing contingency principles for managing short to medium term plant outages.
Proposals for a SIXEP contingency plan that includes long-term provision of alternative capacity.
182. The four composite recommendations are therefore as follows:
Enhance the robustness and performance of SIXEP through a programme of asset care and specific
plant based improvements.
Improve the ability of SIXEP to manage future feed challenges through the completion of critical
technical work packages.
Optimise existing storage capacity for sand and spent ion exchange media, and ensure that
adequate retrieval programmes are in place. Deploy Bulk Storage Tank 13 (BST13) when the
Medium Active Solid Waste Encapsulation Plant (MASWEP) tank ‘A’ and BST 14 are full. Do not
commission MASWEP tank ‘B’ unless it is needed to store an alternative ion exchange medium.
Deliver an operational SIXEP Waste Retrievals (SWR) / Sludge Packaging Plant 2 (SPP2) by 2016 to
ensure compliance with NII Licence specification 326.
Develop and implement a comprehensive SIXEP contingency plan, considering donor plant
management, asset care and new-build options.
4.2.3
Switching feeds from the Segregated Effluent Treatment Plant to the Enhanced
Actinide Removal Plant.
183.
The Sellafield “Gate C” Strategy, issued in March 2006, contained an OES which identified that the volume
of low active effluent arisings remaining after reprocessing operations cease is inadequate (too low) to
enable one of the effluent treatment plants that deals with low activity, high risk effluents (EARP Bulks) to
continue its current operational regime. However, there are a small number of low active, high risk
effluents which must continue to be managed for many years.
184.
In addition, as Sellafield Site moves from a regime of largely commercial reprocessing operations to largely
POCO and decommissioning, effluents currently classified as ‘low risk’ may become ‘high risk’ owing to the
change in operating mode to that of clean-up taking place. Diverting these streams towards EARP Bulks
provides mitigation against this risk.
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185.
The SETP deals with low activity, low risk feeds, and these will also reduce significantly after reprocessing
operations cease. It was determined that EARP Bulks has the hydraulic capacity to accommodate its own
residual feed and SETP residual feeds (see graph below), with the exception of the purge of the Light
Water Reactor (LWR) fuel pond. The LWR pond purge has an existing alternative discharge route via
SIXEP.
Volume Into EARP Bulks
140000
Volume, m3/yr
120000
100000
80000
Combined SETP
Other EARP
Magnox
Volumetric Capacity
LTP2007
60000
40000
20000
20
07
/0
20 8
09
/1
20 0
11
/1
20 2
13
/1
20 4
15
/1
20 6
17
/1
20 8
19
/2
20 0
21
/2
20 2
23
/2
20 4
25
/2
20 6
27
/2
20 8
29
/3
20 0
31
/3
20 2
33
/3
20 4
35
/3
20 6
37
/3
20 8
39
/4
0
0
Figure 17 - Graph showing the impact as SETP feeds are diverted in EARP upon its hydraulic capacity
186.
Diverting the low risk, low active effluents from SETP into EARP enables SETP to cease normal
operations earlier than its currently identified date. Whether SETP undergoes POCO and subsequent early
remediation, or a period of extended care and maintenance subject to SIXEP contingency or
decommissioning options, is to be established.
187.
Therefore the proposed baseline strategy that has been included in 2008 LTP is that when the volume of
residual effluent arisings to SETP and EARP has fallen below the EARP hydraulic capacity, Low Active
Low Risk effluents will be diverted towards EARP Bulks. This extends the operation of EARP, Effluent
Plant Maintenance Facility (EPMF) and WPEP from 2030 to 2040, thus enabling SETP closure to be
brought forward from 2040 to the end of Magnox and Thorp POCO phase (predicted to be circa 2017).
188.
A detailed technical assessment, supported by comprehensive report, has been carried out based on the
OES model for future SETP effluent arisings and the impact of diverting these streams to EARP. In
summary the technical judgement does not identify any significant show stoppers for diversion and
identifies the following key points requiring further assessment:
189.
EARP Bulks is unlikely to remain viable after the cessation of reprocessing due to the small volume of
residual feeds.
• EARP Bulks has the hydraulic capacity to receive and process all residual SETP feeds after cessation
of reprocessing, with the exception of the LWR Pond purge.
• The LWR Pond purge already has an engineered discharge route via SIXEP.
• Of the residual SETP feeds, all were broadly compatible with EARP Bulks apart from the HALES
Caustic Scrubber (due to volatile active species); it may be still possible to divert the HALES Caustic
Scrubber effluent into EARP Bulks without detriment to aerial releases.
• The processing of complexants, although already carried out in very small and diluted batches,
requires better definition regards future arisings.
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•
There is a cost penalty arising from increased generation of floc from EARP, which results in an
increase in ILW product drums: OES modelling indicates around 4000 extra product drums, but this
could be significantly reduced to around 400 if EARP can be demonstrated to operate effectively at
lower iron concentration in the feed.
190.
It is noted that cost benefit is difficult to quantify at this stage of the strategy development. The issue is
complicated by issues of potentially maintaining SETP operational readiness to provide contingency
against irrecoverable outage of SIXEP and possible Decommissioning opportunities. Cost impacts
dependent on strategic use need to be built up during detailed design of the most effective engineered
diversion option for SETP feeds. A cost neutral output would support the option for early diversion.
191.
It is envisaged that the combined residual low risk effluent volume will fall within the capacity of EARP
bulks around the completion of both Magnox and Thorp reprocessing and POCO phases (predicted to be
circa 2017).
192.
Development work is required from now to confirm EARP and WPEP operability, and to identify
modifications required to the Low Active (LA) drainage system (including segregation of the HALES
Caustic Scrubber effluent).
193.
Key Recommendations:
• Assess modifications required to divert SETP feeds into EARP Bulks
• Develop a methodology for carrying out limited development work on actual SETP feeds through
EARP using existing engineered route
4.2.4
Future Low Active Aqueous Effluent Strategy
194.
The OES for Sellafield that was delivered as part of the Sellafield “Gate C” Strategy in March 2006 did not
develop the aqueous effluent strategy beyond 2040 due to the lack of definition of effluent arisings in this
period.
195.
2007 LTP assumed the main existing liquid effluent plants would be closed by around 2040 due to age and
redundancy. EARP closes around 2030; SETP and SIXEP close around 2040. No replacement plants are
proposed. Current infrastructure for low active effluent, surface and groundwater collection and discharge
remain until around 2090 to handle residual effluents. Since the OES was not developed during this
timeframe there are a number of disconnects which need addressing:
• Current assets were designed for the site as it operates now and are unlikely to be fit for purpose
during the radically different site activities taking place from 2040 onwards.
• In order to complete remediation of Separation Area it is necessary to remove the current effluent
collection, treatment and discharge assets.
196.
By 2040, process LA effluent arisings are predicted to have virtually ceased. Residual LA effluent
producers are confined to a small number of plants and support facilities. LA effluent arisings in this time
period are expected to broadly comprise:
3
• Process effluents, mainly from fuel ponds and stores operations (around 25,000 m /year)
3
• Decommissioning effluents (100’s m /year total from all sources)
3
• Contaminated surface and ground water (around 500,000 m /year)
The major volumetric component of liquid effluent will therefore arise from the management of groundwater
and surface water drainage. As Separation Area is progressively remediated the potential activity and
volume of contaminated water will fall.
197.
Proposed baseline strategy for 2008 LTP:
• New East River Effluent Collection System (ERECS) and West River Effluent Collection System
(WRECS) will be provided for LA effluents arising east and west of the River Calder respectively, from
2040 onwards. This will provide Sellafield with two separated LA effluent systems.
• Residual active effluents arising east of the River Calder are treated at source to be suitable or sea
discharge. They undergo accountancy at source, and are collected and discharged via the ERECS
and the existing Calder Interceptor Sewer, possibly via a coaxial pipe laid through the sewer.
• Residual active effluents arising west of the River Calder are treated at source to be suitable for sea
discharge. They undergo accountancy at source, and are collected and discharged via the WRECS
and a new or refurbished sea line.
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•
Minor effluent arisings from decommissioning activities will undergo treatment and accountancy at
source. They will then be transferred by bowser to the WRECS.
Figure 18 – Map showing each of the new effluent collection systems and their discharge routes. The
diagram also shows the expected status of buildings at 2040 according to 2007 LTP.
198.
An alternative strategy under consideration is for effluents generated at East Calder to be pumped across
a pipebridge to the WRECS. This would result in a single sea discharge point for all active effluents.
199.
No site allocation has been made for these facilities yet. WRECS would be expected to be south or south
west of Separation Area, near to the existing sea line route; ERECS would be expected to be in the region
of the Waste Inlet Facility (WIF) and Comprehensive Import Export Facility (CIEF), the main sources of low
active effluent arising.
200.
It is envisaged that the new effluent collection and discharge systems would be operational around 2040.
Development and design of the new systems would be carried out in the 2030s, by which time firmer
assessments of the expected demand, regulatory regimes and stakeholder expectations would be
available.
201.
Major refurbishment or replacement around 2070, coincident with expected completion of Separation Area
remediation, would enable new demand predictions to be accommodated.
202.
The changes to the Sellafield low activity effluent strategy has been assessed using the same
methodology as performed in IWS Version 2. As a result, Figure 19 shows the Sankey diagrams that are
relevant to this strategic change. The top one of the two diagrams shows the situation as reported in LTP
2007, whereas the diagram beneath is indicative of the revised strategy. It is worth noting that there are
two additional streams on the revised Sankey, these are examples of new opportunities that have been
identified since the production of 2007 LTP.
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LTP2007
Wet Inlet Facility Local Effluent Treatment Plant
2505 m3
Misc. Beta Gamma Waste Store
Sellafield Product & Residue Store
Borehole 68
18 m3
Sellafield Effluent Treatment Plant
120 m3
4745 m3
Break Pressure Tank
Thorp Receipt & Storage Local Effluent Treatment Plant
18800 m3
Lagoon
Surface Water
342005 m3
LTP2008 - Opportunity for East & West River Effluent Collection Systems
Wet Inlet Facility Local Effluent Treatment Plant
Surface Water
Comprehensive Import & Export Facility
Separation Area Groundwater Effluent Treatment Facility
Borehole 68
4745 m3
Thorp Receipt & Storage Local Effluent Treatment Plant
18800 m3
2505 m3
56 m3
Sellafield Product & Residue Store
120 m3
Miscellaneous Beta Gamma Waste Store
18 m3
342005 m3
198195 m3
West River Effluent
Collection System
East River Effluent
Collection System
Figure 19 – Sankey diagrams showing the change in strategy since 2007 LTP for the low activity effluent
collection system
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4.2.5
203.
Discharge Trends
The graphs below demonstrate the current predicted discharge trends and also illustrate the current
targets of the UK Discharge Strategy.
LTP 2008 Predicted Dose Attribution from Liquid Effluents allocated to Reprocessing & Decommissioning
30
25
Sv
20
15
10
5
0
2005
2007
2009
2011
2013
2015
2017
2019
2021
2023
2025
2027
2029
Financial Year Starting
Predicted Reprocessing Contribution
Predicted Decommissioning Contribution
UK Discharge Strategy Target
Figure 20 - Predicted trend for dose attributed to liquid effluents, showing the discharge from
reprocessing and decommissioning operations.
LTP 2008 Predicted Total Alpha Attribution from Liquid Effluents allocated to Reprocessing &
Decommissioning
0.4
0.35
0.3
TBq
0.25
0.2
0.15
0.1
0.05
0
2005
2007
2009
2011
2013
2015
2017
2019
2021
2023
2025
2027
2029
Financial Year Starting
Predicted Reprocessing Contribution
UK Discharge Strategy Target
Predicted Decommissioning Contribution
Figure 21 – Predicted trend for total alpha discharges from reprocessing and decommissioning
operations
LTP 2008 Predicted Beta-5 Attribution from Liquid Effluents allocated to Reprocessing & Decommissioning
90
80
70
TBq
60
50
40
30
20
10
0
2005
2007
2009
2011
2013
2015
2017
2019
2021
2023
2025
2027
2029
Financial Year Starting
Predicted Reprocessing Contribution
Predicted Decommissioning Contribution
UK Discharge Strategy Target
Figure 22 - Predicted trend for beta-5 discharges from reprocessing and decommissioning operations
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204.
As can be seen from the graphs above, the discharges due to reprocessing are currently low owing to the
low throughput of the reprocessing plants in recent years. The slight increase in discharges over the next
few years will be due to the planned ramp-up of reprocessing operations to operate closer to previous
rates. Once reprocessing operations cease, the associated discharges will reduce considerably and
quickly, though discharges due to retrievals of legacy wastes and decommissioning operations become
more significant. It can be seen that the projected discharges meet the UK Discharge Strategy target,
though it should be understood that projected discharges due to decommissioning operations inherently
carry a greater degree of uncertainty than those for reprocessing operations. It should also be noted that
the UK Discharge Strategy target does not preclude additional reprocessing business, should the UK
Government choose to progress that opportunity.
4.3 Gaseous Waste Strategy
4.3.1
Update of the Gaseous Waste Strategy
205.
The overall effluent strategy work is also relevant to the IWS. Decisions by the IWSSG are taken with due
regard to the OES work regarding both aqueous and gaseous wastes. The OES is used to inform the
overall Integrated Strategy for Sellafield. With reference to gaseous wastes, the strategy is focused upon
supporting and enabling commercial operations and remediation activities at Sellafield, whilst ensuring
adequate protection of the environment.
206.
Current operations at Sellafield result in several main gaseous effluent streams that have the potential to
contribute to radioactive discharges to the atmosphere. These include:
• Reprocessing Operations
• HLW Treatment
• Spent Solvent Treatment
• Legacy Waste Storage
207.
Reprocessing operations contribute the most towards gaseous discharges. Therefore, once reprocessing
finishes, a significant reduction in amount of gaseous activity released is expected to be seen. Since June
2007 the main contributor to gaseous discharges has been legacy ponds as both HLW Treatment and
Reprocessing Operations have been curtailed owing to a lack of Evaporative capacity for treating HAL
waste.
208.
All significant gaseous waste streams are subject to treatment prior to discharge. The use of these facilities
represents the BPM for minimising discharges, and the application of the WMH. When treating gaseous
streams, emphasis is placed on abatement. The aim of which is to contain the radioactivity in solid or
aqueous form, thus immobilising or mitigating the environmental impact of the activity.
209.
The current Gaseous Waste Strategy remains the same as for the 2007 IWS (Version 2) i.e. the existing
Gaseous Waste Baseline Statement remains the current state of the strategy.
210.
Aspects of the strategy that may be subject to change are:
• The impact of the funding shortfall upon the Separation Area Ventilation (SAV) project,
• Subjective reports of larger than anticipated deflections of the Alpha Plant Discharge Stack during
winter storms.
These are discussed in the sections below.
4.3.2
211.
Separation Area Ventilation Project
Both the first generation reprocessing plant stack (that serves Magnox reprocessing plants, various legacy
and storage plants, and some plants that are being decommissioned) and the Pile 1 stack are nearing the
end of their effective operational lives and are scheduled for demolition in the near future. The objective of
the SAV Project is to divert aerial effluents currently routed to these stacks to a new discharge facility that
will provide a long-term discharge capability to meet current and future operational and decommissioning
needs.
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212.
The SAV project is a critical part of the current gaseous waste strategy. It has recently been subject to a
financial review following the current lack of NDA funding to deliver baseline projects. The review has
further strengthened the case for the SAV project, though it has caused the project delivery to slip by
approximately three months.
4.3.3
213.
The stack that jointly serves the Analytical Services Facility and the Product Finishing & Storage Facility
provides a suitable high discharge point for the ventilation systems of these plants. Routine design checks
carried out as part of the Continued Operation Safety Report (COSR) preparation and visual inspections of
accessible parts of the stack give confidence in the integrity of the structure. Further assurance to allay
concerns of previous subjective reports of larger than anticipated deflections during winter storms is being
performed in the form of instrumentation to assess any movement of the stack over several months; this is
done because of firstly the previous lack of measurement of the deflections and secondly to build on the
confidence of the COSR design checks. All indications to date confirm the stack to be adequate for the
requirements upon it (i.e. at least 5 years). Therefore it is noted that there should be sufficient time to
provide a solution should the monitoring instrumentation indicate any problems with the longer term use of
the stack.
4.3.4
214.
Alpha Plant Discharge Stack
Discharge Trends
The graphs below were produced by the OES Model (OESM) for 2008 LTP, using the best available data
at that time. The graphs refer to predicted aerial discharges from the main (scheduled) stacks on the
Sellafield site, and do not include discharges from Miscellaneous Outlets on the site. It should be noted
that the OESM currently over-predicts aerial discharges and hence the associated dose to the critical
group by a significant margin (an approximate factor of 2.5), for example, in the graph below the dose to
the critical group is predicted to be around 50µSv, but actual discharges were measured closer to 20µSv.
Further improvements to the aerial modelling capability are planned within the OES work, but it may be
several years before modelled predictions become close to actual discharges.
LTP 2008 Predicted Dose Attribution from Aerial Effluents allocated to Reprocessing & Decommissioning
60
50
Sv
40
30
20
10
0
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030
Financial Year Starting
Predicted Reprocessing Contribution
Predicted Decommissioning Contribution
Figure 23 – Predicted trend for dose attributed to aerial effluents, showing the discharge from
reprocessing and decommissioning operations
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LTP 2008 Predicted Total Alpha Attribution from Aerial Effluents allocated to Reprocessing & Decommissioning
3.00E-04
2.50E-04
TBq
2.00E-04
1.50E-04
1.00E-04
5.00E-05
0.00E+00
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030
Financial Year Starting
Predicted Reprocessing Contribution
Predicted Decommissioning Contribution
Figure 24 – Predicted trend for total aerial alpha discharges from reprocessing and decommissioning
activities
LTP 2008 Predicted Beta-5 Attribution from Aerial Effluents allocated to Reprocessing & Decommissioning
7.00E-02
6.00E-02
5.00E-02
TBq
4.00E-02
3.00E-02
2.00E-02
1.00E-02
0.00E+00
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030
Financial Year Starting
Predicted Reprocessing Contribution
Predicted Decommissioning Contribution
Figure 25 – Predicted trend for beta-5 discharges from reprocessing and decommissioning activities
4.4 Decommissioning
4.4.1
Decommissioning Strategy (including mandates)
215.
The most significant change to the Decommissioning Strategy since Version 2 of the Sellafield IWS was
issued (June 2007) has been the inclusion of uncertainties in the assessment of the volumes of waste that
will be generated during decommissioning of Sellafield. This has significantly increased the projected
volumes of waste and hence has directly affected the strategies for treating and disposing of this waste.
The impacts on the affected strategies (e.g. LLW, PCM, ILW, etc) have been discussed in earlier sections
of this report. The full impact of the uncertainties upon the Decommissioning Strategy is unlikely to be
known until 2009 LTP is prepared, as it is inevitably linked to funding, and 2009 LTP will be prepared from
a strategic viewpoint that assumes it is fully-funded.
216.
The programme of revised decommissioning estimate production, formally called the Decommissioning
Mandate process (which are assessments of how to decommission specific plants, together with projected
costs and waste volumes) were subject to scope review in May 2008 to ensure the most benefit is gained
from the work. Decommissioning Mandates have been carried out on 22 plants to date, including the major
facilities on site. This review assessed the output of the mandates performed to date and will direct the
future programme of work on mandates. This will involve consideration of a range of approaches to
decommissioning, including techniques, costs, programmes, etc.
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217.
Those estimates completed so far have given confidence in the revised figures for cost, schedule, waste
volume, etc, together with a slight change in strategic direction towards targeted waste segregation at the
decommissioning workface. The new estimates have also enabled an improved understanding of the state
of the plant following POCO and hence a better idea of the decommissioning start-point – which gives a
better idea of where targeted decontamination may be useful. This is a change from the previous general
approach of remote dismantling and minimal decontamination in more highly-active areas.
4.5 Non-Radioactive Discharges
218.
The Sellafield site received a Pollution, Prevention and Control (PPC) permit in October 2007. Table S1.3
in Schedule 1 of the PPC permit specifies activities required by the EA as part of the permit process.
219.
One of these improvements is the review of fugitive aerial emissions. Initial work has identified the key
aerial non-radioactive species of interest (such as dust, heavy metals, oxides of NOx and SOx) and is now
seeking to use the existing aerial environmental measurements at the site perimeter (using the High
Volume Air Samplers) to prove that emissions of these species from the site are, as anticipated,
insignificant. Should these results be otherwise then further work will be undertaken to improve
understanding.
220.
In the past year the main source of the steam supply to the site, the 3 Combined Heat & Power (CHP)
plant gas turbines, suffered a common mode failure of corrosion of all 3 exhaust stacks. For safety reasons
the heights of the stacks were reduced. As a result, a review was needed to assess the impact of
operating at a lower stack height, and whether the CHP plant could continue to operate in its modified
state. Sellafield Ltd have assessed the affect of reduced stack heights and shown that the increase in
ground level concentrations of nitrogen dioxide to members of the public and key environmental receptors
are small and will have a negligible impact on both human health and the wider environment.
221.
It was concluded that reduced stack heights does not result in a breach of the permitted emission limits,
however it does represent a change to the agreed operating technique. The variation was submitted to the
EA who agreed in February 2008 that discharges from CHP would be acceptable and would not exceed
the limits set on the site for NOx. Therefore the CHP plant can continue to operate, and hence maintain a
reliable source of steam to the site.
222.
A number of facilities on site require and depend on a reliable source of steam. The recent event whereby
the stacks on the CHP steam generating plant were found to be corroded, and therefore their heights
reduced, had the potential to threaten the supply of steam to the site. The decision was taken to maintain
steam production so that site operations could continue. This demonstrates the principles of the IWS and
improved application of the WMH. When assessed, it was considered that the production of steam was
critical to the primary focus of safety and risk reduction. In addition, the issue surrounding the CHP plant
provides an example of the integrated nature of the site, and the inter-dependency of plants.
223.
As part of the PPC permit, Sellafield Ltd is also obliged to:
Take appropriate measures to ensure energy, raw materials & water are used efficiently in the
activities on the site, and to apply the waste management hierarchy appropriately to avoid & minimise
waste generation.
Review every 4 years whether there are suitable opportunities to improve the efficiency of the
activities, and take appropriate measures based upon these reviews.
224.
Continuing to integrate and optimise the Sellafield IWS to fully include non-radioactive wastes is an
ongoing development target for the site.
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5.0
Opportunities, Risks & Uncertainties
225.
At both site level and at the component strategy level there are uncertainties, risks, and opportunities that
impact on, or are relevant to, the IWS.
226.
Uncertainties
The previous version of the IWS (2007) identified the following uncertainties for which Sellafield is
dependant upon national policy/decisions and their resolution:
• Repository design, timing and location
• Decision on the future of LLWR
• UK Policy on plutonium and uranium
• The potential for future use of Sellafield as a national asset for waste management
Since then, two significant additional uncertainties have arisen having the potential to impact on the IWS.
Both the current funding situation and the imminent DEFRA review of the UK Strategy for Radioactive
Discharge 2006-2030 are outside the control of the IWS. When these uncertainties are resolved the
implications will be assessed to inform the IWS.
227.
Risks
There are a number of risks that have the potential to impact upon the Sellafield IWS. These are
summarised at a high level in Table 6 which details the actions being taken to manage these risks.
Table 6 – Potential future risks that may impact upon the Sellafield IWS
Risk
Action to mitigate
LLW
A change in the Condition for Acceptance (CFA) of a future
LLWR may require more stringent processing that currently
employed (e.g. a greater degree of radiometric segregation,
passivation of wastes, etc.)
Constraints on disposal to the current LLWR or the unavailability
of a future LLWR may lead to on-site storage
To be assessed within the developing Sellafield &
national LLW strategy (June 2009)
Inappropriate use of waste routes, e.g. large quantities of
HVVLLW being disposed of to LLWR if not effectively segregated
at source
LLWR costs increasing as capacity becomes more constrained
Uncertainty in decommissioning forecasts may increase LLW
disposal costs
As above, and assessed within the developing
decommissioning strategy
ILW / PCM
Change in Repository Waste Acceptance Criteria – may lead to
greater level of pre-conditioning and/or potential for higher level
of rework on existing packages.
Increased scope for the extent of re-work required than that
currently envisaged (e.g. may have to chemically treat waste
instead of simply over-packing)
Delay in repository availability – wastes would require prolonged
storage, forcing stores to operate beyond current design lives.
Currently being assessed within OU – Final
Treatment and disposal of ILW, and the PCM
Strategy.
Uncertainty on decommissioning and legacy waste forecasts and
characterisation - may increase rework and final disposal costs.
As
above,
and
assessed
decommissioning strategy
within
the
Site Wide Internal
High activity evaporators capacity limits reprocessing throughput
and the clean up of HLW plants
Problems in the LP & LS schedule
Managed within current 2007 LTP and HLW
strategy
As above, and addressed in the LP & LS strategy
Fuel reprocessing is extended
Managed within 2007 LTP and strategies for
Magnox Operating Plan and Oxide Operation
Plant
Managed within the 2007 LTP and the developing
LLW strategy
LLWR reaches capacity
Note: Effluent Risks are not included in this table as the actions to mitigate these have already been
developed to a sufficient extent to be incorporated into the relevant parts of the Sellafield LTP (e.g. SIXEP
Contingency and SETP-EARP switch).
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228.
There remain lower-level risks, specific to the component strategies, which if realised could affect the
tactics of the component strategies. Under such circumstances the ‘flankguard’ role of the IWS is to
ensure that a change in tactics does not affect the intended strategic direction.
229.
Opportunities
There are several opportunities identified in the relevant OU LTPs that are relevant to the IWS. These are
briefly outlined as follows:
230.
Opportunities for LLW
• Potential for treatment plants to become available earlier than scheduled in 2008 LTP if a Private
Finance Initiative (PFI) arrangement is used.
• Significant increase in decontamination if chemical techniques are employed.
• Significant opportunity to recycle and reuse any HVVLLW on-site if demonstrated to be within
acceptable radiological limits.
• Cracking and crushing LLW concrete may allow for better packing efficiency and recovery of re-bar
• Investment in cable stripping would offer significant recovery and sale of valuable materials such as
copper and aluminium.
231.
Opportunities for ILW
Utilisation of existing and planned ILW treatment facilities (e.g. MEP, WEP, BEP, etc) which may
obviate the need for the 1st ILW conditioning plant - Decommissioning Intermediate Level Waste
Encapsulation Plant (DILWEP) – identified in the Final Treatment and Disposal of ILW OU as being
currently required. There may be an opportunity to instead use existing spare capacity and future
LP&LS treatment plant spare capacity to treat decommissioning waste. This requires significant
scheduling work and there is a potential delay to decommissioning. Risk management will be a
significant burden.
3
Potential to use larger packages (than 3m boxes) for decommissioning wastes – this will allow for
more efficient packing.
Decontamination and volume reduction of bulk metals to reduce disposal volumes, costs and apply the
waste hierarchy more effectively.
Increased rate of ILW exports to the repository thereby reducing the overall duration of site storage
and export – cost savings and reduced likelihood of store replacements.
Consolidate final ILW treatment facility with that required for Calder Hall Final Site Clearance.
Decay store significant quantities of lower order decommissioning ILW and remove requirement for
disposal.
Improved characterisation of waste may enable re-categorisation of some waste to a less onerous
waste category
Potential avoidance of some additional stores through reducing the uncertainty around future waste
volumes
232.
All of these opportunities are subject to further assessment of technical underpinning and potential
secondary consequences in order to determine whether it is appropriate to incorporate these changes into
the strategic baseline. As appropriate, these opportunities will then be pursued by the relevant OUs and
component strategies through the LTP process and implementation is being assured via the Strategic
Governance arrangements in place on the site.
6.0
Conclusions & Way Forward
233.
The NDA state that an IWS is a strategy which describes;
•
How a site optimises its approach to waste management in an integrated way.
•
The waste streams and discharges expected from current and future operations.
•
Actions that are required to improve the sites approach to waste management.
234.
In its current form the IWS for Sellafield describes:
235.
How the site approached waste management in an integrated way –
The largely ‘integrated’ position established by Version 2 (June 2007) has been successfully
strengthened in the past 12 months through the tactical deployment of the IWS principles
developed in IWS V2 (2007) within the component waste strategies and OU work plans.
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236.
The waste streams and discharges expected from current and future operations – these predictions
are covered in section 4.
237.
Actions required to improve the sites approach to waste management
This update describes how the actions to improve the sites approach to waste management have been
embedded into the LTP for the site and notes those opportunities for further improvement which are still
being pursued.
238.
Over the past three years the Sellafield IWS has developed from being a statement of the baseline strategy
(Version 1, June 2006) to a mature and live strategy process fully embedded in the site LTP. Since Version
2 considerable progress has been made in translating this strategy into the LTPs for the site. In particular:
• all wastes and routes have been identified
• estimates quantities of waste have been reassessed for both raw and conditioned volumes
• Opportunities have been identified for waste minimisation and the use of existing facilities. These
have either been incorporated into the lifetime or identified for further assessment.
• Strategies for implementation are being developed for LLW, ILW and PCM
• Tools and techniques to facilitate quantification and assessment and to enable the visible
management of wastes information have been developed e.g. Sankey Diagrams in Version 2 and
the OESM.
• The analysis has contributed to the NDA led national strategies in particular ILW and LLW
strategies.
239.
The IWS in its present form fulfils all of the above requirements with the exception of optimisation.
240.
It is difficult to fully optimise the IWS whilst high-level uncertainties remain around funding, waste volumes,
scheduling and waste characterisation. The next ‘step-change’ in IWS development will be achievable
once these uncertainties are sufficiently resolved and optimisation around a set of ‘fixed’ parameters can
be undertaken. In the meantime the Sellafield IWS will continue to integrate and optimise the site’s
component waste strategies within these constraints and will inform and support the development of
national strategies which will help resolve these uncertainties.
241.
Way Forward
The way forward for the component strategies is best summarised in Figure 26, which illustrates the key
timelines for these strategies and how these are influenced by site operations, external influences and
other constraints.
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Figure 26 – Future milestones associated with the IWS
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242.
In the immediate future (2008-09), there is a requirement to produce a combined IWS with the Windscale
licensed site by June 2009. The next iteration of the IWS will also be informed by the emerging Sellafield
and national LLW Strategies.
243.
This update of the IWS has reported and discussed the tactics and deployment of the Sellafield IWS. The
component strategies will continue to implement the principles of the IWS and hence the future
development of the IWS will be as a ‘flankguard’ role to:
• ensure the general strategic direction is maintained, regardless of changes to tactics that may be
needed in the future
• undertake assessment of potential strategic changes initiated by resolution of uncertainties or
changes in assumptions
244.
It is recognised that there is still some implementation work to be done and some opportunities to be
pursued within the LTPs. This work will be undertaken by the relevant OUs with the IWS team (within
Strategy and Transition group) providing a ‘flankguard’ role going forward and using appropriate Strategic
Governance arrangements to ensure delivery.
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7.0
Glossary
Abbreviations
Full Text
AGR
AWE
AGWSG
AWS
Advanced Gas-Cooled Reactor
Atomic Weapons Establishment (at Aldermaston)
Aqueous Gaseous Waste Strategy Group
Aqueous Waste Strategy
Becquerel (Bq)
BEP
BFS
BNFL
BPEO
BPM
BS
C-14
CEAR
CFA
CHP
Ci
CIEF
CILWS
CLESA
cm
COSR
Cs-137
DEFRA
DILWEP
DoE
DQO
EA
EARP
EDS
EN
EPMF
EPS
ERECS
FY
g
HA
HAL
HALES
HAST
HHISO
HLW
HLWP
HVLA
HVVLLW
ILW
ISO
The SI unit of radioactivity. A becquerel is the smallest unit of
radiation – it corresponds to the activity of a quantity of radioactive
material in which one nucleus decays per second
Box Encapsulation Plant
Blast Furnace Slag
British Nuclear Fuels Limited
Best Practicable Environmental Option
Best Practicable Means
British Standards
Carbon-14
Compilation of Environment Agency Requirements
Conditions For Acceptance
Combined Heat & Power
Curie, unit of radioactivity
Comprehensive Import Export Facility
Containerised Intermediate Level Waste Store
Calder Landfill Extension Segregated Area
Centimetres equal to 10^-3 Metres
Continued Operations Safety Report
Ceasuium-137
Department for Environment, Food and Rural Affairs
Decommissioning Intermediate Level Waste Encapsulation Plant
Department of Environment
Data Quality Objectives
Environment Agency
Enhanced Actinide Removal Plant
Engineered Drum Store
Enforcement Notice
Effluent Plant Maintenance Facility
Encapsulated Product Store
East River Effluent Collection System
Financial Year
Gram, SI Unit for Mass
Highly Active
Highly Active Liquor
Highly Active Liquor Evaporation and Storage
Highly Active Storage Tanks
Half Height International Standards Organisation
High Level Waste
High Level Waste Plant
High Volume Low Activity
High Volume Very Low Level Waste
Intermediate Level Waste
International Standards Organisation
© Nuclear Decommissioning Authority 2008, this document contains proprietary information, permission to copy, or use such information,
should be sought from the Intellectual Property Manager, Sellafield Ltd.
Sellafield Integrated Waste Strategy – Update on Version 2
June 2008
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Abbreviations
Isotope
IWS
IWS V2
IWSSG
km
KPI
LA
LFE
LLLW
LLW
LLWR
LP&LS
LSG
LSTP
LTP
LWR
m
MAC
MASFE
MASWEP
MBGWS
MEB
MEP
MOP
ND&MPG
NDA
NII
NNL
NOx
OES
OESM
OPC
OSPAR
OU
PAF
PBI
PBO
PCM
PCRSA
PFA
PFI
PFSTP
PMP
POCO
PPC
PPE
PVC
R&D
REF
RSA 93
Full Text
A subtype of an element – isotopes of an element have the same
number of protons, but different numbers of neutrons. The most
common in nature are stable isotopes, radioactive isotopes are
unstable – radiation is a by-product of an isotope moving towards a
stable form.
Integrated Waste Strategy
Integrated Waste Strategy Version 2
Integrated Waste Strategy Steering Group
Kilometre, equal to 1000 metres
Key Performance Indicator
Low Active
Learning From Experience
Low Level Liquid Waste
Low Level Waste
Low Level Waste Repository
Legacy Ponds & Legacy Silos
(National) Low Level Waste Strategy Group
Local Sludge Treatment Plant
Lifetime Plan
Light Water Reactor
Metre, SI Unit for Distance
Medium Active Concentrate
Medium Active Salt Free Evaporator
Medium Active Solid Waste Encapsulation Plant
Miscellaneous Beta Gamma Waste Store
Multi Element Bottle
Magnox Encapsulation Plant
Magnox Operating Plan
Nuclear Decommissioning & Major Projects Group
Nuclear Decommissioning Authority
Nuclear Installations Inspectorate
National Nuclear Laboratory
Nitrogen Oxides
Overall Effluent Strategy
Overall Effluent Strategy Model
Ordinary Portland Cement
Oslo-Paris European Union Convention
Operating Unit
Performance Agreement Form
Performance Based Incentive
Parent Body Organisation
Plutonium Contaminated Material
Post Closure Report Safety Assessment
Pulverised Fuel Ash
Private Finance Initiative
Pile Fuel Cladding Silo Treatment Plant
Plant Modification Proposal
Post Operational Clean Out
Pollution, Prevention & Control
Personal Protective Equipment
Poly Vinyl Chloride
Research & Development
Residue Export Facility
Radioactive Substances Act 1993
© Nuclear Decommissioning Authority 2008, this document contains proprietary information, permission to copy, or use such information,
should be sought from the Intellectual Property Manager, Sellafield Ltd.
Sellafield Integrated Waste Strategy – Update on Version 2
June 2008
Page 61 of 61
Abbreviations
Full Text
RWMAC
SAV
SDP
Radioactive Waste Management Advisory Committee
Separation Area Ventilation
Silos Direct Encapsulation Plant
Sellafield Ltd
The new name for British Nuclear Group, Sellafield Ltd operates the
Sellafield site on behalf of the NDA
Segregated Effluent Treatment Plant
Site Funding Limit
The SI unit of dose equivalent. A Sievert is a measure of biological
dose – which is the biological impact of radiation. A Sievert is a large
impact and hence most discharge impacts are measured in small
fractions of this i.e. thousandths (mSv) or millionths (µSv).
Site Ion Exchange Plant
Site Ion Exchange Plant Operating Plan
Site Ion Exchange Plant Operating Strategy
Site License Company
Sulphur Oxides
Sludge Packing Plant
Strontium-90
Sellafield Site Procedure
SIXEP Waste Processing Plant
Site Ion Exchange Plant Waste Retrievals
Technical Baseline: Underpinning Research & Development
Technicium-99
Tonne (equal to 1000kg)
Thermal Oxide Reprocessing Plant
United Kingdom
United Kingdom Atomic Energy Agency
United Kingdom Nuclear Waste Management Limited
Very Low Level Waste
Vitrified Product Store
Vitrified Residue
Waste Materials and Compaction
West Cumbria Site Stakeholder Group
Waste Encapsulation Plant
Waste Inlet Facility
Waste Management Hierarchy
Waste Packing and Encapsulation Plant
West River Effluent Collection System
Waste Treatment Complex
Waste Vitrification Plant
Alpha, in reference to alpha radiation
Beta, In reference to beta radiation
SETP
SFL
Sievert
SIXEP
SixOP
SixOS
SLC
SOx
SPP
Sr-90
SSP
SWP
SWR
TBURD
Tc-99
te
THORP
UK
UKAEA
UKNWM
VLLW
VPS
VR
WAMAC
WCSSG
WEP
WIF
WMH
WPEP
WRECS
WTC
WVP
© Nuclear Decommissioning Authority 2008, this document contains proprietary information, permission to copy, or use such information,
should be sought from the Intellectual Property Manager, Sellafield Ltd.
Sellafield Integrated Waste Strategy – Update on Version 2
June 2008