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Predisposal Management of RAW
Overview of Predisposal Management
Peter Lietava (peter.lietava@sujb.cz)
ANSN RWMTG Regional Workshop
Waste Safety Practices and Establishing Regulations for Predisposal Management
Daejeon, South Korea
4 – 8 July 2011
Predisposal Management of RAW 2
Overview of Publications
Predisposal Management of RAW 3
Outline of Lecture • Responsibilities
- Legal, regulatory and policy
framework
- Responsibilities of the operators
- Responsibilities of the regulator
- Integrated approach to safety
• Steps in predisposal
management
- Generation of RAW
- Processing of RAW
- Storage of RAW
- WAC
• Development and operations
• Example of regulations
Predisposal Management of RAW 4
Roles and Responsibilities
Legal, Regulatory and Policy Framework
• The government shall provide:
- for an appropriate national legal and regulatory
framework;
- protection beyond national borders.
• The policy and strategy shall be:
- appropriate for the nature and the amount of
the RAW;
- shall indicate the regulatory control required;
- shall consider relevant societal factors; and
- shall form the basis for decision making with
respect to the management of RAW
Predisposal Management of RAW 5
• Responsibilities of the regulator; he shall:
- establish the requirements for the development of
RAWM;
- review and assess the SC and the EIA ;
- provide for the issuing, amending, suspension or
revoking of licences, subject to any necessary
conditions;
- carry out activities to verify that the
operator meets these conditions;
- take enforcement actions as necessary by
the regulatory body in the event of deviations from, or
non-compliance with requirements and conditions.
Roles and Responsibilities
Responsibilities of the Regulator
Predisposal Management of RAW 6
Roles and Responsibilities
Responsibilities of the Operator
• Responsibilities of the operator; he shall:
- be responsible for the safety of predisposal
radioactive waste management facilities or
activities;
- carry out safety assessments and develop a
safety case; and
- ensure that the necessary activities for siting,
design, construction, commissioning, operation,
shutdown and decommissioning are carried out in
compliance with legal and regulatory
requirements.
Predisposal Management of RAW 7
Roles and Responsibilities
Integrated Approach to Safety
• Measures shall be implemented
to ensure an integrated approach
to safety and security in the
predisposal RAWM
• Interdependences among all
steps in the predisposal RAWM,
as well as the impact of the
anticipated disposal option, shall
be appropriately taken into
account
• Management systems shall be
applied for all steps and elements
of the predisposal RAWM
Predisposal Management of RAW 8
Steps in Predisposal Management – I. • All waste management steps prior to disposal,
including processing of:
- Operational waste;
- Cleanup waste; and
- Decommissioning waste.
• Waste processing is intended to produce a waste
form compatible with the selected
RAWM strategy.
• Processing generally encompasses
one or more of following activities:
- Pretreatment;
- Treatment;
- Conditioning. Conditioning of sludges in NPP Temelín
Predisposal Management of RAW 9
Steps in Predisposal Management – II.
• Handling, transport,
storage, and disposal
of conditioned waste
must be considered;
• Safe storage of waste
during processing;
• Processing approach
needs not to exclude
potential disposal
options.
STUDSVIK large components management
Pretreatment
Treatment
Predisposal Management of RAW 10
Steps in Predisposal Management
Waste Generation
• All RAW shall be identified and controlled. RAW
arisings shall be kept to the minimum practicable
• At various steps in the predisposal management of
radioactive waste, the radioactive waste shall be
characterized and classified in accordance with
requirements established or approved by the
regulatory body
Predisposal Management of RAW 11
Steps in Predisposal Management
Processing – I. • Pretreatment:
- Reduces amount of waste subject to further
processing or disposal;
- Adjust characteristics to make waste
more suitable to plans for
additional processing and disposal.
• Treatment:
- Enhance safety in the short-term by
making immediate improvements
in characteristics;
- Part of longer-term steps towards safe
predisposal management;
- Fit within overall plan considering interdependences
Supercompactor
Predisposal Management of RAW 12
Steps in Predisposal Management
Processing – II.
• Conditioning:
– Produce a solid waste form
compatible with handling,
transport, storage and
disposal plans;
– Solidification media may be
added;
– Waste packaging suitable
for normal and accident
conditions.
Cemented RAW
Predisposal Management of RAW 13
Structure of Predisposal Management
Storage • Storage:
- During predisposal steps,
storage may be necessary;
- Storage may be used to allow
decay prior to authorized
discharge, use, clearance, or
eventual disposal;
- Storage can occur in many
forms and any stage of
predisposal (e.g., raw, treated,
conditioned).
Gorleben RAW store
Storage chamber for used sources (Richard repository)
Predisposal Management of RAW 14
Steps in Predisposal Management
WAC
• Waste packages and unpackaged waste that are
accepted for processing, storage and/or disposal
shall conform to criteria that are consistent with the
safety case
Predisposal Management of RAW 15
Safety case has a role throughout the lifecycle for a
predisposal facility:
• Integrating relevant scientific (and other) information
• Demonstrating that consideration has been given to
the subsequent steps of management and their
compatibility
• Identifying uncertainties in the performance of the
facilities
• Demonstrating operational safety
Development and Operations
Safety Case – I.
Predisposal Management of RAW 16
•Aiding decision making on the authorisation / licensing
of the facilities.
– Siting – identify suitable locations
– Design – identify necessary barriers and features
– Construction
– Commissioning – specify WAC and oper. conditions
– Operations – procedures developed to avoid
initiating events and for response in the event of
accidents
– Decommissioning
•Facilitating communication amongst stakeholders on
issues relating to the facilities.
Development and Operations
Safety Case – II.
Predisposal Management of RAW 17
• Safety Assessment as a part of safety case:
- Demonstrate that the facility can be operated in compliance with safety requirements;
- Identify hazards and safety features, procedures, etc. required to maintain safety;
- Iterative process to improve design and operations (siting -> design -> … -> decommissioning);
- Normal and abnormal conditions;
- Graded approach based on hazards.
Development and Operations
Safety Case – III.
Predisposal Management of RAW 18
• The operator shall prepare a safety case and a
supporting safety assessment
• The safety case shall include a description of how all
the safety aspects of the site, the design, operation,
shutdown and decommissioning of the facility, and
the managerial controls satisfy the regulatory
requirements
• The safety case + assessment shall be documented
at a level of detail and to a quality sufficient to
demonstrate safety, to support the decision at each
stage and to allow for the independent review ...
Development and Operations
Safety Case – IV.
Predisposal Management of RAW 19
• The operator shall carry out periodic safety reviews
and shall implement any safety upgrades required
by the regulatory body following this review. The
results of the periodic safety review shall be
reflected in the updated version of the safety case
for the facility
Development and Operations
Safety Case – V.
Predisposal Management of RAW 20
Development and Operation
Development of Facilities – I. • Basic siting and design criteria:
- Graded approach considering hazards associated
with waste;
- Facilities sited to reduce need for transport;
- Capacity should be sufficient to process potential
waste volume and store waste;
- Potential to process waste from large sources
such as accidents and major facility modifications.
• Predisposal RAW management facilities shall be
located and designed so as to ensure safety for the
expected operating lifetime under both normal and
possible accident conditions + decommissioning
Predisposal Management of RAW 21
Development and Operation
Development of Facilities – II. • Detailed design criteria:
- Proper shielding and containment; - Access and waste movement controls; - Retrieval of stored waste; - Waste characterization and inventory controls; - Waste inspection, including containment; - Non-conforming waste handling;
- Control of effluents; - Ventilation + filtration;
- Non-radiological hazards; - Maintenance and
decommissioning;
- Fire protection; - Criticality prevention;
- Safeguards and security controls
Predisposal Management of RAW 22
Development and Operation
Structure of SA
• Determines the framework for the
assessment activity to be performed
• Site conditions, facilities and activities,
waste
• Scenarios are postulated / assumed
sets of conditions and/or events
• Conceptual model, mathematical
model and computer code
• Optimization of protection, sensitivity
analysis, engineering analysis
• Independent verification
• Review and modification of models
Predisposal Management of RAW 23
Development and Operation
Graded Approach • In accordance with the graded approach, the extent
and complexity of the safety assessment will vary
with facility or activity type and with the level of depth
of the
safety assessments
performed at the different
stages of the development
of a facility or activity.
• BSS require use of a graded approach towards
safety
• Classify facilities or practices according to safety
significance, maturity and complexity
Predisposal Management of RAW 24
Development and Operation
Other Provisions
• For facilities subject to agreements on nuclear
material accounting, in the design and operation of
predisposal RAW management facilities the
system of accounting for and control of nuclear
material shall be implemented in such a way so as
not to compromise the safety of the facility
• The safety at existing facilities shall be reviewed to
verify compliance with requirements. Safety related
upgrades shall be made by the operator in line with
national policies and as required by the regulatory
body
Predisposal Management of RAW 25
Defence in Depth
Objectives
Defence in Depth refers to redundant barriers to:
• Compensate for potential human and component
failures;
• Maintain the effectiveness of the barriers by
averting damage to the facility and to the barriers
themselves;
• Protect workers, members of the public and the
environment from harm in accident conditions in
the event that these barriers are not fully effective.
Predisposal Management of RAW 26
Example of Regulations – I. • Licensee responsibility:
– licensee is responsible for all safety aspects of the nuclear facility including RAW managed therein;
– at each step of RAW management, responsibility must be determined for RAW at the facility where they are handled, between the RAW generator and the licensee
• RAW classification, characterisation and minimisation:
– Based on activity, radioactive wastes are classified into the following classes:
Transient radioactive wastes ...,
Low-activity and intermediate-level radioactive wastes, whose activity ... (short-term RAW < 400 Bq/g ..., long-term RAW ≥ 400 Bq/g,...),
High-level wastes....;
Predisposal Management of RAW 27
Example of Regulations – II. – Characterisation of radioactive wastes means
determination of their physical,chemical, and radiological properties for the purposes of their management;
– Radioactive waste processing means that the maximum quantity of usable substances is separated and returned for reuse so that the quantity of resulting RAW is minimised
• Definition of RAW management:
– the methods of RAW management that require a licence under the ... include pretreatment (collection, sorting, processing), treatment, storage and disposal.
• RAW pretreatment (collection, segregation, processing):
– RAW are collected and sorted depending on the manner of their further processing and treatment and with respect to their activity and physical, chemical, and biological properties. As far as technically possible, collection and sorting is performed directly at the point of RAW generation
Predisposal Management of RAW 28
– Container used for RAW collection are labelled so that it is obvious what RAW they contain;
– Before RAW processing, consideration shall be given to the impact of the processed and arising substances on the reliability of the technological equipment used for waste processing, as well as the impact on the technologically related systems to avoid any adverse impact on nuclear safety or radiation protection;
– If RAW processing makes use of ion exchangers, filtration or other separating substances of a limited life, their function shall be inspected on a regular basis, and the licensee shall determine the highest values upon the exceeding of which these shall be refurbished or replaced. The licensee shall specify the aforementioned values in the corresponding operating instructions.
Example of Regulations – III.
Predisposal Management of RAW 29
– If RAW is incinerated, a technological incineration procedure shall be set out and documented for each type of waste, which the licensee shall specify in corresponding operating instructions. The licensee shall also monitor corrosive effects of combustion products on the facility construction materials, and take measures should nuclear safety be compromised.
• RAW treatment
– The licensee shall propose a technological procedure, conditions of RAW treatment, materials, and container used;
– RAW shall be treated by changing its physical or chemical properties, or by enclosure in a container; this shall be carried out in such a way as to ensure safe transport, storage and disposal.
Example of Regulations – IV.
Predisposal Management of RAW 30
• RAW conditioning
– For RAW conditioning by solidification media such as cement, bitumen or glass, the licensee shall determine a technological procedure in the operating instructions, which shall include, among other things, the blending ratio or specific consumption of solidification media and hardening conditions. The operating instructions shall also set out the acceptance criteria for solidification media and a method of verification to assure their desired quality.
– If the conditioned RAW is filled in packages, provisions shall be made to avoid their overfilling.
– If RAW conditioning includes packaging, such packages shall be selected which can reliably withstand stress resulting from subsequent manipulation and transport, ensuring their safe handling.
Example of Regulations – V.
Predisposal Management of RAW 31
Example of Regulations – VI. • Safety case and safety assessment
– The licensee shall provide a safety case and use it as a basis for continuous support of safe operation throughout the lifetime of a facility;
– The safety case shall cover both the facility itself and the waste and their respective safety-relevant features. The safety case shall include a description of how all the safety aspects of the site, the design, construction and operation, as well as provisions for decommissioning of the facility, and the managerial controls satisfy the regulatory requirements;
– The licensee shall update the safety case to reflect
modifications and new regulatory requirements and relevant standards
results of the periodic safety review
Predisposal Management of RAW 32
results from analyzis of incidents
as soon as practicable and in accordance with safety relevance of the modification after the new information is available and applicable;
• The licensee shall carry out at regular intervals a review of the safety of the facility (PSR). The review shall be made periodically, at a frequency which shall be established by the national regulatory framework (e. g. every ten years).
Example of Regulations – VII.
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