predisposal management of raw overview of predisposal … documents... · 2013. 12. 3. ·...

Predisposal Management of RAW

Overview of Predisposal Management

Peter Lietava ([email protected])

ANSN RWMTG Regional Workshop

Waste Safety Practices and Establishing Regulations for Predisposal Management

Daejeon, South Korea

4 – 8 July 2011

mailto:[email protected]

Predisposal Management of RAW 2

Overview of Publications


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


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


• 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.


Responsibilities of the Regulator



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.



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


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


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


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



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



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


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)



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


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.


•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.


Safety Case – II.


• 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.


Safety Case – III.


• 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 ...


Safety Case – IV.


• 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


Safety Case – V.


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



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



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



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



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


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.


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....;


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


– 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.


– 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.


• 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.


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


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.

predisposal management of raw overview of predisposal … documents... · 2013. 12. 3. ·...

Documents