Decommissioning of the LURE Synchrotron RadSynch 17 NSRRC, Hsinchu, Taiwan April 19-22, 2017 Jean-Michel HORODYNSKI Pierre ROBERT

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1 Decommissioning of the LURE Synchrotron RadSynch 17 NSRRC, Hsinchu, Taiwan April 19-22, 2017 Jean-Michel HORODYNSKI Pierre ROBERT

2 Summary 2

3 LURE: A Second Generation Synchrotron Plant Building of the first part of the LINAC 2/1956-8/1962 Building of the second part of the LINAC 4/1965-8/1968 First beam in DCI 3/1977 First beam in CLIO FEL 6/ /1965 First beam in ACO collision ring 5/1987 First beam in Super ACO 12/2003 LINAC, Super ACO and DCI stopped 3

4 Map of the LURE Synchrotron 4

5 Goals of the Decommissioning Project Initial state LINAC, Super ACO and DCI stopped ACO as a museum CLIO (FEL) running Final State LINAC, Super ACO and DCI decommissioned ACO as a museum CLIO (FEL) running PHIL (electron LINAC, 9 MeV) running 5

6 Dismantlling of non-radioactive parts : modulators and oils contaminated with PCB abestos 2006 : partial dismantling of the Super-ACO ring for material transfers towards research centers Planning of Dismantling Works for the LURE Synchrotron Plant Non-radioactive parts were dismantled first Licensee need to be delivered to dismantle radioactive parts Declassification only if final state previously declared is reached Files to obtain license to begin dismantling of radioactive parts (Ministerial decree) Dismantling of radioactive parts : Super ACO, DCI and LINAC Elimination of radioactive waste Files to obtain declassification of the INB106 Available in the incoming paper 6

7 Radiation Protection During and After the Decommissioning Decommissioning of the LURE Synchrotron 7

8 Radiation Protection during the LURE Decommissioning Tools and Methodology Risk management is based on its assessment and continuous improvement. Radiation protection assessments of the decommissioning work History of the exploitation (many years of exploitation => many changes) Knowledge of the beam physics (identification of beam losses) Radiological measurements (in-situ or on samples) Numerical tools (Monte-Carlo/Deterministic codes) 8

9 Radiological Assessmements of Decommissioning Works 9

10 Available in the incoming paper 10

11 Specific Activity of Concrete and Activation Witnesses Along the Electron Part of the LINAC and the Convertor Area 1E+02 Variation of the activation along the LINAC The level of activation do not vary linearly with the beam energy. -Radiation protection: dose rate map - Radioactive waste management: activation level depending on various parameters Bq.g -1 1E+01 1E+00 1E-01 1E-02 1E E-04 Meter (0: electron gun) CONVERTOR AREA Aluminum - Stainless Steel - Concrete - 11

12 Radiation Protection Optimization using planning 1st Phase: Super ACO (lowest radiological risks) 2 nd phase: DCI (low radiological risks, seperated building) 3rd phase: LINAC (medium radiological risks) 4th phase: Convetor Area (highest radiological risks, area seperated from the LINAC gallery) 12

13 Radiation Protection during the Decommissioning Phase Worker H p (10) (µsv) H p (0,07) Time during active dosimeter was used h 04 min h 03 min h 22 min h 13 min Above: individual dosimetry( operational dosimeter) results during the disassembly of the convertor (task exposing to the highest level of radiation) Actual collective dose for the whole phase: 1 msv.man Internal exposure: no contamination and cutting works stricly limited and done with dustless tools (saber-saw, pipe-cutter ) 13

14 Complete Decontamination of the Building Walls? The choice must be based on: Potential radiological impact on public and environment (decontamination, on-site use or site demolition) Technical constraints Financial costs 14

15 Specific Activity vs Depth in Concrete in Convertor Areas of the LURE LINAC 1.2 LURE Radiological Risk Assessment LINAC Convertor areas Concrete activation SPECIFIC ACTIVITY (BQ.G-1) cm 5-10 cm cm cm cm cm DEPTH IN CONCRETE R5 Convertor Old R8 Convertor 15

16 LURE - Radiological Impact Assessment: Walls Decontamination not made Radiological impact were assessed if LURE most activated walls were not decontaminated Worst case: use of the building for private purpose From 2020, maximum efficient dose integrated during one year will be inferior to 1 msv According to the radiological impact assessments and technical constraints, walls of the convertor area were not decontaminated. Efficient dose Adults (µsv) Infants 0-1 year (µsv) ,56 e 3 1,98 e ,15 e 2 9,08 e ,74 e 2 4,75 e 2 16

17 LURE Decommissioning Final State A minimal period survey of the area has been established, until 2020, where access are strictly restricted and works which may alter the walls are strictly forbidden. Since December 2015, LURE synchrotron is declassified 17

18 Radioactive Waste Management Decommissioning of the LURE Synchrotron 18

19 LURE Decommissioning Radioactive Waste Management European regulations define free-release thresholds for activated waste French regulations do not apply it: Radioactive waste management based on a Waste radioactive Zoning approach Identification of areas where radioactive waste may be produced: Radioactive Waste Zoning Definition of VLLW (Very Low-Level Waste) category and availability of a final disposal center (Cires, ANDRA) 19

20 Radioactive Waste Management Process Radioactive Waste Zoning Dissassembling - Production Dose rate measurements Conditionning Transport to ANDRA disposal Applications files for ANDRA disposal Radiological characterization (Gamma spectrocopy) 20

21 Radioactive Waste: Packaging Two types of packaging were used: ISO 20-feet half-height container. Unit pieces. 21

22 Radioactive Waste: Packaging ISO 20-feet half-height container Filling optimized to reduce void Empty parts must be arrange to ease sand filling in the disposal 22

23 Radioactive Waste: Packaging Unit pieces Parts that can not be placed in a standard packaging Weights between 100 kg to 25 tons Handling parts or furnitures available 23

24 Radioactive Waste: Numbers and Feedbacks Phase 1 Super ACO Phase 2 DCI Phase 3 LINAC Weight (tons) Volume (m 3 ) ISO 20 feet halfheight Unit pieces Phase 4 Convertor Total

25 Feedbacks for Next Synchrotron Decommissioning Design phase Reduce the amount of potential radioactive waste: no electronic devices near the machine, use of concrete with a low level of Europium is needed Design accelerator parts reducing needs of cutting process for future dismantling 25

26 Feedbacks for Next Synchrotron Decommissioning Exploitation phase Recording of every changes, events on the installations (machines and building) is mandatory QA plan Knowledge of beam losses (localisation, levels ): Dose rate measurements, activation samples, beam loss monitoring 26

27 Feedbacks for Next Synchrotron Decommissioning Pre-decommissioning phase Definition of the type and the composition of the project team: knowledge of the installation, new skills, technical and administrative jobs (Safety, radiation protection, IT, financials ) Critical risks for planning: time for application files with national authority following local regulations (about half of the time dedicated to these tasks for LURE decommissioning) 27

28 Feedbacks for Next Synchrotron Decommissioning Decommissioning phase Radiological risk assessment: Localization of the critical area regarding external exposure risks Optimization of the radiological risks: planning, shielding, methods Radiation protection team is a key element of the project team Reusing of existing building for scientific purposes is a way to improve environment impact of our scientific tools. 28

29 irsd Expertise and Consulting on Radiation Protection, Radioactive Waste Management, Safety and Decommissioning CNRS unit dedicated to expertise and consulting for research nuclear plant: accelerators, radioactive sources, X-ray generators Radiation Protection: Measurements, Management, Monte-Carlo code Safety: Design of interlocks system for accelerators, X-ray generators Decommissioning: Planning, Financial assessments 29

30 irsd Expertise and Consulting on Radiation Protection, Radioactive Waste Management, Safety and Decommissioning References: SOLEIL Synchrotron: Financial assessment of the decommissioning; Assessment of concrete activation using Monte-Carlo code CERN: Review of the Radioactive Waste Management ThomX (production of X-rays by ICS, electron accelerators): Shielding design, radiological assessment, activation assessment, radioactive waste management plan, interlocks system Cilex Apollon (High-Power laser (1-10 PW) on solid or plasma targets): review of interlocks system and radiation protection application files. 30

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