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Consequently, practices and regulations differ from
one country to another.
Today, in accordance with IAEA recommendations,
French policy aims to ensure that BNI licensees adopt
an immediate dismantling strategy.
This principle currently figures in the regulations
applicable to BNIs (Order of 7th February 2012, the
“BNI Order”). It has been included in the doctrine
established by ASN for BNI decommissioning and
delicensing since 2009 and has just been taken up
at legislative level in the Energy Transition for Green
GrowthAct (TECV). This strategymoreover avoids placing
the technical and financial burden of decommissioning
on future generations. It also provides the benefit of
having the knowledge and skills of the teams present
during operation of the installation, which are vital
during the first decommissioning operations.
French policy for the management of very low-level
radioactive waste does not include a system of clearance
levels for this waste, but requires that it be managed in
a specific route so that it remains isolated and traceable.
This is why, with regard to the possible recycling of the
waste resulting fromdecommissioning, ASN is attentive
to the application of French doctrine for radioactive
waste which states that contaminated waste or waste
that could have been contaminated in the nuclear sector
may not be reused outside this sector (see chapter 16).
Similarly, the risks associated with Social, Human
and Organisational Factors (SHOF) (due to changes
in organisation with respect to the operating phase,
frequent use of outside contractors, and risks associated
with loss of memory) must be taken into account.
Lastly, the sometimes rapid changes in the physical
state of the installation and the risks it presents raise
the question of ensuring that the means of surveillance
used are adequate and appropriate at all times.
1.2 The ASN doctrine concerning
decommissioning
1.2.1 Immediate dismantling
The International Atomic Energy Agency (IAEA) has
defined two possible decommissioning strategies for
nuclear facilities following final shutdown:
•
deferred dismantling: the parts of the installation
containing radioactive materials are maintained or
placed in a safe state for several decades before actual
decommissioning operations begin (the “conventional”
parts of the installation can be decommissioned as
soon as the installation is shut down);
•
immediate dismantling: decommissioning is started as
soon as the installation is shut down, without a waiting
period, although the decommissioning operations
can extend over a long period of time.
The IAEA considers that safe enclosure (or entombment),
which consists in placing the parts of the installation
containing radioactive substances in a reinforced
containment structure for a period that enables a
sufficiently low level of radiological activity to be
reached with a view to releasing the site, is no longer a
possible decommissioning strategy, but may be justified
in exceptional circumstances.
Many factors can influence the choice of one
decommissioning strategy rather than another: national
regulations, social and economic factors, financing of
the operations, availability of waste disposal routes,
decommissioning techniques, qualified personnel,
personnel present during the operating phase, exposure
of the personnel and the public to ionising radiation
resulting from the decommissioning operations, etc.
ENERGY TRANSITION
FOR GREEN GROWTH ACT (TECV)
Changes brought by the TECV:
• When the licensee plans to definitively stop the operation
of all or part of its installation, it must notify the Minister
responsible for Nuclear Safety and ASN at least two years
before the planned shutdown date, or as quickly as possible
if the shutdown is implemented with shorter notice for reasons
justified by the licensee. This notification is made known
to the CLI (Local Information Committee) and made available
to the public.
• The licensee is no longer authorised to operate the installation
as from final shutdown of the installation.
• The licensee is obliged to submit its decommissioning file
no later than two years after giving notification of its intention
to definitively shut down its installation.
• Any installation that has been shut down for at least
two years is considered to be definitively shut down and
must be decommissioned (this period can however
be extended to five years under special circumstances).
ASN is contributing to the ongoing updating of the Decree
of 2nd November 2007 relative to the BNI decommissioning
procedures, and on 28th January 2016 it issued an opinion
on the draft decree updating the procedures governing BNI final
shutdown and decommissioning.
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CHAPTER 15:
SAFE DECOMMISSIONING OF BASIC NUCLEAR INSTALLATIONS
ASN report on the state of nuclear safety and radiation protection in France in 2015