ICEM11 Final Program 9.7.11pm_ICEM07 Final Program ... - Events

Session 26 Abstracts
7) A SUCCESSFUL TRANSITION FROM OPERATING TO DISMANTLING
A UO2-PUO2 FUEL FABRICATION FACILITY (w/oP-59326)
Thierry Flament, AREVA NC (France)
After fabricating plutonium fuels for 40 years (Fast bredder reactor, Mox), commercial operations at the AREVA Cadarache
plant ended in 2003 and post operation clean out of its production building and laboratory started. AREVAs objective is to achieve
the clean-up of the process facilities and to transfer them to their owner, the French Atomic Energy Commission. The completion
of this operation demonstrates the possibility to dismantle plutonium fuel fabrication facility and the possibility to reuse the facilities.
The facilities to be dismantled by AREVA at Cadarache include:
About 420 glove boxes containing various types of equipment (process equipment for nuclear fuel fabrication, analytical equipment
to characterize fabricated fuel, process equipment to recover valuable materials (Uranium and plutonium) and calcine liquid
effluent),
• About 40 storage tanks
• 3 major steps in this large D&D programme
• Recovery of fissile materials left in the facility led by a project team:
• 25 metric tons of mixed oxide materials in the various glove boxes / storage were recovered in less than 5 years...
SESSION 26 — D&D TECHNOLOGIES - PART 1 OF 2 (3.4)
1) DISMANTLING/REMEDIATION OF A HIGHLY CONTAMINATED SUMP
IN RUNNING PLANT CONDITIONS (w/oP-59053)
Jos Boussu, Koen Lenie, Tecnubel (Belgium)
A sump in the RPE circuit in the EDF - Nuclear Power Plant of Cruas-Meysse, showed a extremely high radiation dose rate
since 2007.
Different attempts to decontaminate the sump did not have the desired effect.
The sump is a so-called gatte where two flows of different fluida circulates. A chemical flow transverses the sump within stainless
steel piping, the second flow which is (contaminated) residual water, flows through this sump in contact with the sumps walls.
The dose rate was estimated at 20 Sv/h, and it was presumed being a single hotspot in the dead zone of the sump, where no
chemicals from the chemical decontamination attempts, and no high pressure water contact had been possible, or had any effect.
To protect the maintenance and exploitation people from the radiation, the sump had been protected with a physical protection
system, named a sarcophage. The client asked to leave this protection system, which was modular, on place during the dismantling
works to assure its radiation protection function.
The paper describes the remote controlled dismantling of the sump within the particular running conditions of the power plant,
the developments made to the equipment, and the conditions in which the works had to be carried out.
Some lessons learnt and particular points of attention are revealed to complete this paper.
2) NEW DEGREASING FORMULATIONS FOR THE DECONTAMINATION OF SOLID SUBSTRATES,
CONSISTENT WITH VITRIFICATION PROCESS OF THE FINAL WASTES (w/oP-59166)
Jeremy Causse, Cyril Roussignol, French Atomic Enrgy Commission; Jean-François
Valery, Jean Charles Hamel, Areva NC (France)
Decontamination shops use various techniques to decontaminate solid substrates. The aim of these shops is either to recover
the substrate for a future second life, or to sufficiently lower the radioactivity level in order to reduce the final waste volume. One
of these techniques remains in aqueous bathes possibly under ultrasonic agitation. This technique is very fit to small metallic pieces.
Most of those pieces are covered with various greases or organic oils very resistant to classical aqueous washes. Thus, this oily
layer contains some unfixed radionuclides that must be removed to reach the decontamination factor targeted. This urged decontamination
shops operating staff to consider additive molecules necessary to render aqueous washes consistent with such a contamination.
These molecules, namely surfactants, act on the liquid surface to increase affinity between aqueous and oily phases.
The surfactant formulations used in French decontamination shops are industrial formulations. Those formulations are generally
designed by international manufacturers to be consistent with several applications. Thus, there isnt any specific formulation fitted
to nuclear applications. But, this way of working is no longer possible now. This is due to the changes of final wastes conditioning
matrix. Indeed, bitumen matrix is devoted to disappear in the next…
3) THE ORION SCANSORT SOIL SORTING SYSTEM (w/oP-59385)
Jeffrey Lively, MACTEC (USA)
Radiologically contaminated sites undergoing remediation or decommissioning typically have large volumes of soil which are
heterogeneously contaminated by radioactivity from historic operations. There is a severe shortage of available disposal space for
this type of material worldwide. It is, therefore, important that volumes being disposed are minimized as far as possible to ensure
efficient use of scarcely available radioactive waste disposal facilities. There are also significant cost savings to be realized from
segregating clean and exempt material from material classified as low-level (radioactive) waste (LLW) for disposal in other (nonradioactive)
facilities or preferably for recycling onsite as part of the site closure process.
The use of a proven dynamic measurement and soil sorting technology has the potential to speed up site closure, reduce LLW
volumes, and save the decommissioning programs significant costs. Conveyor-based, radiological soil measurement systems developed
have been used to process bulk soils with the potential to be contaminated with radioactivity, segregating soils that exceed the
accepted regulatory limits from those that could be reused onsite or otherwise disposed in non-radioactive disposal facilities. This
paper will describe the operation and advanced capabilities of MACTECs state-of-the-science bulk soil survey and sorting system
developed and successfully used in the USA…
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