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Regulatory Guide - Possess or Control and Extended Shutdown of a Facility or Source

Last updated date: 
1 March 2021
Reason for update: 
Amendment to address suggestion S06 of the 2018 IRRS report – mainly to cover extended shutdown

1. Introduction

This document describes the purpose of a ‘possess or control’ licence and the principles that determine the scope of activities that may be undertaken by a licence holder during a period of possess or control. This document also describes ARPANSA’s expectations for periods of extended shutdown outside of a possess or control licence. Licence holder plans and arrangements should include information on how it will manage safety and security during an extended shutdown (both planned and unexpected) and the return to operation or the transition to possess or control, decommissioning or disposal. These plans and arrangements should be in place during normal operation or use in readiness for an unexpected period of extended shutdown.

Possess or control most often applies to nuclear installations and prescribed radiation facilities, but the same general principles may also be applied to controlled material and controlled apparatus (sources). A possess or control licence is a type of facility licence (See ARPANSA Act s30). It is most commonly issued for a prolonged period (usually years) of safe enclosure between periods of routine operations or leading to decommissioning of the facility. It is usually characterised by a period of minimal activity. An extended shutdown is a significant period (usually months) where a facility is not used, usually due to some unforeseen circumstance, but where the normal licence/authorisation remains in place and where operation or use may resume.

The general principles described in this document are based on international guidance and principles of the International Atomic Energy Agency (IAEA).  This document provides supplementary information relating specifically to extended shutdown or possess or control licences and must be read in conjunction with other applicable Regulatory Guides. Particular attention is drawn to the ARPANSA Regulatory Guide: Plans and Arrangements for Managing Safety, and the Holistic Safety Guidelines.
This guide assists ARPANSA to provide a predictable and consistent approach the assessment and inspection of controlled facilities and sources. It provides information to ARPANSA’s assessment and inspection team that should be considered in assessing licensing and compliance requirements. This guide also provides information to applicants and licence holders on its expectations for possess or control and extended shutdown of controlled facilities. While focussing on facilities, the principles described in this guide can be applied to the control of radioactive sources and other controlled apparatus and is consistent with the guidance of codes and standards applying to source licences.

2. Guideline structure 

This guide comprises four main sections.

  • Section 3 provides information on ARPANSA’s expectations for activities and arrangements that should be undertaken during a, usually unplanned, extended shutdown of operation (without a possess and control licence).
  • Section 4 provides information regarding the general intent and principles of possess or control. It provides definitions and how possess or control relates to specific authorisations under the Australian Radiation Protection and Nuclear Safety Act 1998 (the Act).
  • Section 5 discusses ARPANSA’s expectations on preparation for possess or control and particularly on reducing the reliance on active safety systems to provide safety.
  • Section 6 discusses the scope of activities that are usually permitted under possess or control licences for facilities.

3. Extended shutdown under an operating licence

From time to time it may become necessary to shutdown normal operation of a controlled facility. Commonly the shutdown is short-lived and counted in days to perhaps a few weeks. In these short-term shutdowns, it is acceptable for licence holders to continue with normal operational safety controls and arrangements. 

Occasionally, a facility may need to be shut down for an extended period. Where the reasons for the extended shutdown cannot be quickly resolved, a decision regarding the long-term future of the facility may be made, for example to transition to a possess or control or a decommissioning licence. This decision should be made within an appropriate period during which the facility and its operating organisation, should be maintained so that operation may resume safely.

This section of guidance regards an extended shutdown before a decision is made on the long-term future of the facility. As a component of its normal operating plans and arrangements, the licence holder should assess the risks of associated with an extended shutdown (including the transition to and from the shutdown) and provide plans and arrangements that ensure safety during an extended shutdown:

  • Appropriate measures are undertaken so that SSCs (structures, systems, components) or materials important to safety or security of controlled material do not prematurely or unknowingly seriously degrade, possibly leading to an impairment of functionality, loss of integrity or radioactivity release.
  • The organisation retains the competencies necessary to operate the facility or have detailed plans on how these competences will be re-established prior to resuming routine operations
  • Where practicable, the facility is made passively safe so that reliance on active safety or security systems is minimised. Measures may include the removal and secure storage of bulk process materials including fissile materials and radioactive waste; post operational cleaning to remove non-fixed and readily removable surface contamination and the removal of energising systems where appropriate to render the apparatus inoperable. Where this is impracticable, normal operational safety controls should be maintained or interim measures to ensure that the safety and security of the facility or source should be implemented.
  • Operational limits and conditions, surveillance and maintenance requirements appropriately reflect the safety requirements of an extended shutdown.

Where a source licence is issued, ARPANSA expects controlled apparatus and sources to be managed in accordance with the licence. This licence will usually require compliance with relevant codes and standards that contain specific requirements for its safe and secure storage when it is not being used. In other instances, ARPANSA expects controlled apparatus or sources to be managed similarly to a facility, i.e. the source should be safely and securely stored and inadvertent use should be prevented. The licence holder is expected to maintain a capability to look after the source and demonstrate it remains safe and secure at all times. 

In implementing these arrangements, due attention must be made to compliance with the Act, Regulations and relevant licence conditions.

4. Possess or control: general principles

A possess or control licence is one of five types of facility licences that may be issued for a nuclear installation or prescribed radiation facility under subsection 32(1) of the Act. Possess or control is also a type of ‘dealing’ relevant to source licences that may be authorised under subsection 33(1) of the Act.

Possess or control for facilities

A possess or control facility licence may be used to authorise a period of care and maintenance between other licensed activities for nuclear installations or prescribed radiation facilities (see Figure 1). A possess or control licence is most commonly relevant to that period of safe enclosure between the operation of a facility and its decommissioning and ultimate disposal (or deferred dismantling). However, it may also be issued to cover other circumstances including a prolonged period of shutdown pending a resumption of operation or periods between decommissioning phases. A possess or control licence may also be issued if the CEO reduces the authority granted by the licence under subsection 36(2) of the Act.  

Diagram of transition through facility licence types. Series of shapes and arrows showing interaction between the transition

Figure 1: Transition through facility licence types. The blue arrows show the preferred route for licensed activities. The red arrows show other possible alternative routes for a possess or control licence. This figure accounts for the majority of cases in which a possess or control licence may be used.

Possess or control for sources

Unlike facilities, there is no specific possess or control licence for sources. However, Section 13 of the Act describes three dealings that may be authorised by a source licence; to possess or have control; to use or operate; or to dispose of the apparatus or material (which is then subject to s65 of the Regulations). The CEO of ARPANSA may exclude one or more of the dealings authorised by a source licence under subsection 33(1) of the Act. This approach may be taken for various reasons, for example “operate or use” may be excluded following the acquisition of a source before the organisation has established a capability to use it, or where safety concerns in its operation have become apparent. In these examples any risks of operate or use are removed whilst maintaining the controlled apparatus or radioactive source under regulatory control. See Figure 2. 

Diagram showing components of the General Source Licence Authorisation

Figure 2: Three Dealings are usually permitted under a source licence. However, where appropriate the CEO may exclude one or more from the authorisation.  

Objective of possess or control

The objective of possess or control is to ensure that, despite not being in use, a controlled facility remains safe and secure.

It is important that the controlled facility or apparatus is not operated and controlled material is not used or disposed where a possess or control licence has been issued. Any facility decommissioning activities require separate approvals under the Act and are therefore prohibited under a possess or control licence.

Consistent with the definitions in the table below, possess or control ‘activities’ are generally regarded as those in which any parts of a facility containing radioactive contaminants are either processed or placed in a condition for safe storage and maintenance until subsequently approved for operation or decommissioning. Decommissioning is the subsequent decontamination and/or dismantling of structures, systems and components to levels that permit the facility to be released for unrestricted use or with ongoing restrictions imposed by the CEO of ARPANSA.

In general, ARPANSA takes the position that the dismantling or removal of any radioactive or contaminated item1 within a facility with the intention of never reassembling it or replacing it is decommissioning and is not permitted under a possess or control licence. The sections below explain certain exemptions from this position.

Key definitions
Operation Operation is the conduct of all activities to achieve the purpose for which the approved facility. This includes maintenance, refuelling, in-service inspection and other associated activities [1].
Extended shutdown A significant period where the facility, apparatus or material is not used but where the normal licence authorisation remains in place and where operation or use may resume. It is usually measured in months. Extended shutdowns may be planned (for example for program or budgetary reasons) or unplanned (for example resulting from a breakdown or other problem).
Possess or control

For facilities, possess or control is the strategy in which all or part of a facility containing radioactive material is either processed or placed in such a condition that it can be put in safe and secure storage and the facility maintained until it is subsequently, approved for operation, decommissioned or otherwise released from regulatory control. Possess or control may involve dismantling of some parts of the facility and early processing of some radioactive material and its removal from the facility, as preparatory steps for the safe storage of the remaining parts of the facility.

Similarly for sources, possess or control is the strategy in which controlled apparatus or controlled material is maintained safely and securely until it is subsequently approved for use or disposal or otherwise released from regulatory control.
Note: This definition of possess or control is adapted from the definition of ‘deferred dismantling’ of IAEA General Safety Requirements - GSR Part 6 – Decommissioning of Facilities [2].

Decommissioning

Decommissioning is the administrative and technical actions taken to allow the removal of some or all of the regulatory controls from a facility. The term decommissioning does not apply to a repository or to certain nuclear facilities used for mining and milling of radioactive materials, for which closure is used [1].

The term ‘closure’ refers to the administrative and technical actions directed at a repository at the end of its operating lifetime and the termination and completion of activities in any associated structures [1].

5. Preparation for possess or control

Any application for a possess or control licence must meet the requirements of the Act. 

To remove or reduce the reliance on active safety and monitoring systems ARPANSA expects a prescribed radiation facility or nuclear installation, wherever possible, to be made passively safe before it is placed under a possess or control licence. Where this is not possible the controlled person should provide justification along with a detailed plan of how this will be achieved including completion dates and acceptance criteria.

The measures to achieve passive safety that will usually be permitted include:

  • Removal of bulk process materials directly related to the previous operational period (including fissile material, process liquids and operational waste)
  • Post operational cleaning to remove non-fixed and readily removable surface contamination  
  • Where pre-existing, operational practices exist, the in-situ decontamination or temporary removal for decontamination within another facility provided the decontaminated item will return to the original system afterward.
  • The removal of readily removable activated or contaminated items where the controlled person can demonstrate that its removal is necessary to the ongoing safe storage of the remaining parts of the facility 
  • The installation of additional structures, systems or components required for safety purposes during the possess or control period;  examples may include the installation of additional shielding, containment or special monitoring systems

In instances where an application for a possess or control licence is made and there remains a possibility to resume operation at some future date, the applicant should ensure that the facility or source is maintained so that no SSCs or materials important for safety, unknowingly degrade so as to cause the safety of future operation to be compromised. The operating organisation should ensure that worker competencies can be demonstrated before routine operations are resumed/reinstated.

6. Activities permitted under a possess or control licence

Possess or control periods are typically periods of low activity especially when a state of passive safety has been achieved and there is little or no reliance on active safety systems. However, ARPANSA expects that monitoring and maintenance is appropriately resourced and managed in order to maintain the source inventory in a safe state. These arrangements should cover all systems, structures and components (regardless of their radiological state) which are necessary to maintain the facility, apparatus or material in accordance with the relevant possess or control safety case and any licence conditions.

In addition to the requirement to maintain the controlled facility and source inventory in a safe state, the table below identifies other activities which are commonly permitted at a facility under a possess or control Licence. The table must be read in conjunction with any licence conditions imposed on the licence.

Non-routine activities
Radiological Characterisation

To facilitate planning for decommissioning, licence holders are permitted to undertake a program of in-situ measurements, sampling and analysis required for radiological characterisation of the facility. Where necessary to facilitate the characterisation process safely, ARPANSA may approve the dismantling of structures, systems and components containing levels of radioactivity above the exemption limits set out in Schedule 1, Part 1 of the Australian Radiation Protection and Nuclear Safety Regulations 2018 (the Regulations).

These activities must take account of licence conditions. The licence holder would normally be required to provide information on any planning of characterisation work, implementation progress and results in its quarterly report to ARPANSA.   

Dismantling

Dismantling of structures systems and components is permitted where the radioactive content is below the exemption levels specified in the Regulations and where it is not required for the future safety of the facility (including during decommissioning). Dismantling of radioactive structures, systems or components may be permitted for the purpose of refurbishment or radiological characterisation.

The licence holder should provide information on any planning of dismantling work, its implementation progress and results of radiation and contamination surveys undertaken with its quarterly report to ARPANSA.
Note: The intent of these restrictions is to prevent any de-facto decommissioning taking place under a possess or control licence.

Refurbishment

The licence holder may undertake refurbishment work at the facility including refurbishment of radioactive and contaminated structures, systems and components. Refurbishment may include the dismantling of existing structures, system and components even when it is radioactive or contaminated.

Where refurbishment is undertaken the licence holder should maintain, upgrade or replace a structure, system of component with an appropriate replacement of the same design function. 

The licence holder should provide information on any planned refurbishment work and its implementation progress with its quarterly report to ARPANSA.

Upgrade (new systems)

The construction and installation of additional structures, systems and components may be undertaken for the purpose of safety improvements or to facilitate a resumption, for example, of future operation or decommissioning of the facility. Where these upgrades are undertaken to meet a future requirement, it should take account of any regulatory requirements pertaining to the facility and is undertaken at the licence holder’s commercial risk.

These activities must take account of licence conditions. The licence holder should provide information on any planning of upgrade work and its implementation progress with its quarterly report to ARPANSA.

While the above information generally relates to facilities, the general principles can also be applied to sources. See section 3 for further information.

Reference Documents

[1] IAEA Safety Glossary – Terminology Used in Nuclear Safety and Radiation Protection (2018 Edition)
[2] IAEA Safety Standards – General Safety Requirements Part 6 – Decommissioning of Facilities


1 Radioactive materials that are under regulatory control are those above the exemption limits in Schedule 1 Part 1 of the Australian Radiation Protection and Nuclear Safety Regulations 2018 unless otherwise exempted.