Want to make interactive content? It’s easy in Genially!

Over 30 million people build interactive content in Genially.

Check out what others have designed:

Transcript

Disposability

Process and Requirements

CONTENTS

Aim of Disposability Assessment

Questions

Overall approach to assessments

Evaluations and Safety Assessments

Staged Assessment Process

NWS Guidance

Aim of DISPOSABILITY aSSESSMENT

2

3

4

1

To boost Confidence

Proof of combatability

To show compliance

To Identify Risks

1

2

3

4

5

6

staged assessments

Waste Stream(s)

Packing/Packaging

Conceptual

Interim

Direct to Final

Targeted

7

Final Stage

–Container-only now consider example streams that might use it

–If waste being placed in container with delayed encapsulation can treat two processes separately, e.g. Final for packing, Conceptual for final packaging–Must have an idea of the encapsulation process and have demonstrated it’s feasible, just not detail

–Plans/ designs being developed–Need confidence WP understands the waste–Aim to identify areas/ issues of potential concern–Proposed concept may be changed either as a result of for other reasons

–Process developed to stage where can design/ build plant–Expect evidence that process will produce wasteform with required properties

–Plant built/ commissioned–MS fully developed

Streams being added to LoC

WP want advice on a specific aspect of the process, e.g. assay requirements

Key Definitions

Transport container/package

Waste

Encapsulation

Packaging

Disposal Container

Immobilisation

Conditioning

Packing

Any 'overpack' for transport and combination disposal package/transport container

Something that no longer has any use. It can include secondary wastes; those generated during operations

Similar to encapsulation but better for mobile wastes

Typically adding cement to solids => Wasteform. - NWS considering alternative terms Separate cap and internal containers considered separately

Completing the disposal package: final disposal unit

The outer 'RWM' container. It may also be the transport container

Placing waste into disposal container. It may involve internal containers, currently part of waster or new.

Preparing the waste for disposal, including encapsulation

Vision for Evaluation reports

Vision

Waste Packager makes submission to responsible SWMS WMS nominated to undertake assessment Preliminary review to check there’s sufficient info etc AQP to define which evaluations are required, who will do them and scope External contractors as required- need a price to pass onto customer Cost estimate => customer, but usually commence work before order placed Undertake evaluations partially in series Key evaluations define inputs to safety assessments before those can start All evaluations/ assessments reviewed by competent person, and agreed through Project Review (PRM) with final checks for consistency Potentially multiple rounds of change WIs detail the overall process and requirements for individual evaluations Supported by templates that may provide useful additional information Although assessments would be done under our QMS, they would have to meet the RWM “spec”

Always the first evaluation May not be required at later stages if no changes Needed to define waste package composition for consideration in other evaluations/ assessments Understand waste as-stored and as completed packages Origins often provide info relevant to understanding Total amounts and distribution between packages Define average and max content of materials and individual RN Max content may consider: limits applying during packaging, i.e. controls on content; uncertainties

Material composition of wastes/ wasteforms, i.e. masses and volumes MUST identify any trace/ unusual materials Not just trade names, but what the materials are chemically Need to define its physical form, particularly surface areas of metals Radionuclide content and variability As much detail as possible Proposed packaging process Detail needed later How wastes get into the container Any pretreatments Need to link to UK RWIs if possible NWS needs to understand if their current information used for planning is accurate

Where each piece of info came from originally, not just where last used If presenting sample analyses, detail of sampling not just results and outline methods Elemental analysis (potentially of inactive samples) just as important in many cases as RN: definition of precursor concentrations for modelling Justification that data is correct/ appropriate - admit concerns/ using judgement Assess ALL uncertainties- potential need for statistical analysis

Typically, a stand-alone report describing wastes in detail WP provide their own average and max package content estimates NWS will review this & check calcs and may do their own calculations if not happy or ask for revision All references to be provided So don’t cite background/ unnecessary information as then copies need to be kept by all. Similarly, avoid sensitive info if possible. Evidence that all calculations have been verified Avoid citing old spreadsheets if you can easily just repeat any “unique” calculations

Based on data generated from N&Q/ provided separately Information on wasteform development varies greatly and may be provided in various ways The waste packager should do this and NWS assess adequacy of arguments Assess the expected wasteform composition and properties How would it meet minimum standards in the WPSGD? Consider all potential variations in composition: envelope Has development work demonstrated that quality products are produced over the full range Consider how wasteform will age (see “product performance status report”) Estimate how much pressure metal corrosion would generate- could it disrupt the matrix/ container Estimate gas generation from corrosion, radiolysis, microbes at disposal & backfilling see “Gas Status Report” Estimate maximum releases of RA gases at disposal and backfilling Final stage, NWS will check appropriate controls being applied and limits defined in WPrS

Conceptual – likely no specific info available, base on experience Interim – should have something specific, i.e. reliable estimates Final – unless things have changed, e.g. new trials, looks more at results of commissioning Full-scale trials/ inactive commissioning often produce a package using simulant and section to demonstrate infiltration Active commissioning would normally involve producing several packages with the real waste, but may include sampling and analysis

At Interim Stage, WP is required to provide (draft) Criticality Compliance Assurance Documentation (CCAD) Assesses validity of choice of Safe Fissile Mass, i.e. arguments Based on N&Q, assesses if amounts of FM would be compliant with the SFM Tips: Keep CCAD as simple as possible Don’t include fissile mass estimates, just method for calculating Be clear about what controls, if any, are required to ensure compliance Admit uncertainties/ what might go wrong that could cause more FM to be present than estimates and how controls prevent that

2

Your content is liked, but only engages if it's interactive.Capture your audience's attention with an interactive photograph or illustration.

1

Your content is appreciated, but it only engages if it's interactive. Capture your audience's attention with an interactive photo or illustration.

To give waste packager (WP) confidence that the packages they intend to produce will be disposable at GDF. The following are some key points in this process:

  • Transportable - Compatible with arrangements and requirements of IAEA transport regulations
  • Handable with proposed equipment and compatible storage arrangements
  • It will not give rise to unacceptable risks at GDF
  • It will not cause post-closure discharges to exceed anticipated limits

Confidence

Each evaluation is a customer deliverable and is updated at each stage, starting from the Conceptual stage (e.g., Issue 1, Issue 2). Each evaluation stands alone, providing a complete view of the current situation without referencing previous versions, except in the "History of Interactions" section. The process may be complicated by adding expert views, and significant changes are needed when updating evaluations done under the previous approach. Instead of a compiled "disposability assessment report," a brief summary is now provided along with the individual evaluation reports, excluding safety assessments.

3

Your content is liked, but only engages if it is interactive. Capture the attention of your audience with an interactive photograph or illustration.

  • For example, this may include the potential introduction of new container designs or the acceptance of non-conforming packages under special arrangements.

To show compliance

Demonstrate compliance with the key underlying assumptions, while noting that these assumptions can be modified through the RWM change control process.

The Nuclear Decommissioning Authority (NDA), through Radioactive Waste Management Ltd (RWM), is tasked with carrying out UK Government policy on the long-term management of higher activity radioactive waste, as outlined in the Implementing Geological Disposal White Paper [1]. This document provides a framework for the long-term disposal of higher activity radioactive waste via geological means, which will be implemented in conjunction with the continued interim storage of waste packages and related research efforts.

Generic Guidance on the preparation of submissions for the disposability assessments of waste packaging proposals

Geological Disposal

Proof of Compatibility

Compatibility considered through a series of evaluation that define parameteres to feed into safety assessments.

To Identify Risks

Identifiy risk of non-disposable packages being accepted - risk transfers to NWS

The Nuclear Decommissioning Authority (NDA), through RWM is responsible for implementing UK Government policy for long-term management of higher acitivity radioactive wastes.

This document forms part of the waste package specification and guidance documentation (WPSGD), a suite of documents prepared and issued by Radioactive Waste Management Ltd (RWM).

An overview of the RWM Disposability Assessment Process

Geological Disposal