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2.3.2 Comurhex plant in Pierrelatte
Operated by Areva NC, this plant mainly produced
uraniumhexafluoride (UF
6
) for the fabrication of nuclear
fuel. Alongside this main activity, the Comurhex plant
produced various fluorinated products such as chlorine
trifluoride.
The production of UF
6
fromnatural uraniumwas carried
out in a part of the plant subject to ICPE regulations,
while the production of UF
6
from reprocessed uranium
was carried out in a part of the plant constituting a BNI.
This part, BNI 105, which was definitively shut down
in 2008, essentially comprises two units:
•
the 2000 unit, which transformed reprocessed uranyl
nitrate UO
2
(NO
3
)
2
into uranium tetrafluoride (UF
4
) or
uranium sesquioxide (U
3
O
8
);
•
the 2450 unit, which transformed the UF
4
from the
2000 unit into UF
6
. This UF
6
was intended to enrich
the reprocessed uranium for the manufacture of fuel.
In May 2011 the BNI 105 licensee had submitted a first
final shutdown and decommissioning application file
which had been judged incomplete.
In February 2014 Areva NC submitted a new final
shutdown and decommissioning authorisation
application. Following the licensee’s responses to the
requests for additional information necessary for the file,
further requests were transmitted to Areva NC relative
to the soil remediation strategy in particular.
2.3.3 Eurodif plant at Tricastin
The Eurodif Production facility, licensed in 1977, mainly
consisted of a plant for separation of the isotopes of
uranium using the gaseous diffusion process, with a
nominal annual capacity of 10.8 million separative
work units.
Following stoppage of its production in May 2012,
Eurodif Production was authorised in May 2013 to
implement the operations of the Eurodif project for
intensive rinsing followed by venting “Prisme”), which
consisted in repeatedly rinsing the gaseous distribution
circuits with chlorine trifluoride (ClF
3
), a toxic and
hazardous substance which allows the extraction of
virtually all the residual uranium deposited in the
barriers.
In accordance with the Decree of 24th May 2013, the
licensee filed its final shutdown and decommissioning
application for the installation in March 2015.
Examination of its admissibility revealed that further
information was required before the examination could
Areva NC, Tricastin site, Comurhex and Comurhex 2 plants.
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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