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the light of the conclusions of the last periodic safety
review of the installation and its age. Eventual findings on
the operating lifetime of CIS bio international’s current
installations show that it would be prudent to adopt
a final shutdown date at the latest within the next ten
years for the evaluation of the decommissioning costs.
ASN recommends that CIS bio international update
without delay the discounting of its costs mentioned
in Article L. 594-1 of the Environment Code, taking
into account a more realistic operating time.
1.5 Lessons learned from
the Fukushima Daiichi accident
To take into account the lessons learned from the nuclear
accident that occurred at the Fukushima Daiichi nuclear
power plant in Japan, ASN asked the BNI licensees to carry
out stress tests, including on installations undergoing
decommissioning.
With regard to EDF, at the request of ASN, the stress
test reports for the BNIs undergoing decommissioning
(Chinon A1, A2 and A3, Saint-Laurent-des-Eaux A1
and A2, Bugey 1, Chooz A, Superphénix, Brennilis) and
the Fuel Evacuation Facility (APEC) (Creys-Malville)
were submitted on 15th September 2012. ASN gave its
conclusions on 10th October 2014. It considered that
the procedure followed complied with the specifications
and asked for further information relative to the seismic
risk in the APEC and the gas-cooled reactors, and the
flood risk in the gas-cooled reactors. EDF has already
committed itself to taking several of these demands
into account.
With regard to the CEA installations, the Plutonium
Technology Facility (ATPu) (Cadarache) currently
undergoing decommissioning was the subject of
resolution No. 296 of 26th June 2012 setting out
additional requirements in the light of the conclusions of
the stress tests. In addition to the generic requirements,
ASN askedCEA to keep up to date the estimated quantities
of fissile materials present in each area within the
ATPu. ASN did not however consider it necessary to
set “hardened safety core” requirements for this BNI.
ASN resolution of 26th June 2012, issued subsequent to
the transmission on 15th September 2011 of the stress
tests report for the Phénix reactor (Marcoule), sets out
additional requirements to reinforce the robustness of
the installation against extreme situations, notably by
establishing a “hardened safety core”. The ASN resolution
of 8th January 2015 also sets additional prescriptions
specifying the requirements applicable to the “hardened
safety core” of the Phénix reactor and the management
of emergency situations.
ASN has not issued prescriptions for the Rapsodie
reactor (Cadarache), for which the report was issued
on 13th September 2012. Nevertheless, CEA has
undertaken to review the scenario of a sodium-water
reaction induced by rainfall occurring further to an
extreme earthquake having caused severe structural
failure of the BNI buildings. The corresponding study
was submitted at the end of 2014 at the request of ASN.
The report concerning the Irradiated Materials Facility
(AMI) operated by EDF at Chinon was submitted on
6th June 2014. ASN considered on 10th July 2015 that the
measures adopted by EDF to mitigate the consequences
of an accident situation associated with extreme external
hazards, such as those taken into consideration for the
stress tests, were satisfactory, subject to removal in the
short term of the radiological inventory present in the
installation.
The experience feedback from the Fukushima Daiichi
accident will be taken into account for the facilities
of lesser importance later on, notably during the next
periodic safety reviews for the Procédé and Support
BNIs (Fontenay-aux-Roses).
The installations whose decommissioning work is
sufficiently far advanced, or whose potential source
term is very low and for which delicensing is very close,
are not concerned by the stress tests.
1.6 The international action of ASN
in the area of decommissioning
ASNparticipated in various international actions relating
to decommissioning in 2015.
It contributed in particular to the WENRA “Waste and
decommissioning” working group which in June 2013
published a report identifying the reference safety
levels applicable to the decommissioning of nuclear
installations. These reference safety levels must be
transposed into the national regulations of each of the
WENRA member countries. Publication of the Order
of 7th February 2012 allowed a number of these safety
levels to be transposed, relating to safety management in
particular, but other measures still have to be specified
in ASN resolutions, notably the resolutions relative to
the studies of waste management in the installations
and to decommissioning, currently under preparation.
ASNisalsoamemberoftheInternationalDecommissioning
Network (IDN) coordinated by the IAEA and as such
keeps itself informed of the international projects. It
has contributed in particular since 2012 to the CIDER
(Constraints to Implementing Decommissioning and
Environmental Remediation) Project, which aims to
identify and develop aids to overcome the difficulties that
member countries can encounter in site decommissioning
and rehabilitation projects.
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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