TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE
IAEA, VIENNA, 25-28 NOV. 2013
CHARACTERIZATION OF LARGE VOLUME OF WASTE, LARGE COMPONENTS AND SOILS
Lucien Pillette-Cousin AREVA TA
Contents
General considerations regarding waste characteristics in case of nuclear accident
Experience from characterization of decommissioning waste
Experience from characterization of large components/waste packages
Characterization of contaminated soils and sites
Example of characterization applied to legacy waste: remediation of the Gremikha site
Nucléaire et renouvelables : Concluding remarks deux énergies complémentaires pour un mix avec moins de CO , 2 économique et fiable.
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Waste characteristics in case of nuclear accident General considerations (1)
Factors affecting quantity of waste from clean-up are (not limited to): Large amounts of various physical nature Extent, depth and nature of contamination Characteristic of environment affected (urban, forest, agriculture etc.) Meteorological conditions Decision on handling the affected area e.g. stabilization, interdiction or clean-up Clean-up methods Clean-up criteria applied
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Waste characteristics in case of nuclear accident General considerations (2)
Facility design
Accident scenario
Dismantling strategy
Selective deposition of radionuclides
Access to contaminated site and damaged facilities
High background conditions for in-situ radiological characterization
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Characterization methods for D&D waste Non destructive Dose rate and dose rate conversion method
Gamma spectrometry (even underwater)
Gamma camera Hot spots, fuel fragments)
Coupling of gamma camera and dose rate measurement
Coupling of gamma spectrometry and neutron measurement: passive (active)
Sampling and radiochemical analysis For determination of scaling factors (correlation factors) for difficult to measure nuclides: pure beta, alpha nuclides (to be used carefully)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Sampling by drilling instead of coring: the TruPro® methodology
Principle: to collect all drilled material as a unique representative sample. Drilling less invasive than coring, ~ 12 mm hole as opposed to 25–50 mm hole for coring - time to obtain each sample is lower (hours min.) Samples are smaller homogenization easier and radioanalytical measurements faster Applicable to slabs, walls, concrete, glass, refractory block, granite, sand, dry soils
Quicker feedback on contaminated areas, reduction of exposure for workers, time saving for the project.
Good experience feedback at Brennilis NPP (France) on reinforced concrete through layers of 10 cm to 2.5 meters thickness, with 3 x 50 cm incremental samples
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Example of methodology for non destructive characterization of D&D waste (simple scene)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Example of methodology for non destructive characterization of D&D waste: complex geometry modelling
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Field Dose Rate Measurements
Well known and easy method for field measurements
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Radiological characterization of large components
In situ gamma spectrometry measurements of large size NPP components Steam generators (before and after decontamination) Vessel lids (e.g. EdF, France) Ground prototype of nuclear submarine (vessel, steam generator)
Gamma spectrometry under Sampling for correlation factors pure beta: Ni-63, Nb-94, etc.. the lid (Co-60, Cs-137)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Use of In-Situ gamma spectrometry
Verification of thermal exchanger (top left),
of raw waste (top right), in collimated geometry
and measurement of contamination in a room in open geometry (left)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Use of In-Situ gamma spectrometry
Characterization of the pool of Triton research reactor (CEA, France) before cleanup and decommissioning (height 9m)
In-situ gamma spectrometry accomodates many characterization geometries / configurations as it is usually the case for nuclear accident
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Comparison of detectors for gamma spectrometry
Room Θ
With collimation / filtration
/ dose rate
Liquid N2 Θ
= f(time of characterization Room Θ after accident) Good compromise
Choice would also depends on time after accident and decay of very short lived radionuclides
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Radiological characterization of large size waste packages
Big-bags 1 to 2 m3 1 to 5 m3 concrete or metal containers ISO containers
Scintillation (NaI, LaBR3) or germanium detector Main concern: modelling and associated uncertainty: Distribution of activity inside the waste package Distribution of waste matrix and density inside waste package
3m3 container: assay in 30 minutes 0.01 Bq/g typical detection limits for Co-60
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Radiological characterization of large size waste packages Measurement of ISO container with ISOCS system (for verification of waste clearance) at Dukovany NPP (Czech republic)
Applicable to VLLW, LLW, ILW
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Radiological characterization of large size waste packages Many data processing systems developed for characterization of large size items, for activity localization and improvement of modelling ISOCS®, LABSOCS® Mercurad ® Particle Swarm Imaging (PSIM) MCNP calculations
Radball ®: suitable for use in hotcells, gloveboxes or enclosed areas of high radiation: used at Sellafield, proposed for Fukushima cleanup
Based on absorption of gamma radiation on a photographic film inside the ball
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Radiological characterization of large size D&D waste packages: Neutron Measurements Non destructive characterization of Pu / U content
Usually not needed for D&D waste if fuel non damaged (used for D&D of reprocessing plants)
Useful in case of severe accident with fuel damaged, e.g. A1 (Slovakia), Chernobyl, Fukushima, for determination of alpha content in waste, coupled with ϫ spectrometry (Cs-137, Pa-234m)
Result as mass of equivalent Pu-240 - Alpha isotopy taken from fuel characteristics with decay/evolution time since accident
Performances in accordance with waste acceptance criteria of the disposal facility (e.g. Vektor characterization facility – ϫ spectrometry not enough to verify compliance of waste from Chernobyl exclusion zone with WAC)
Scaling factor method for pure beta emitters
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Radiological characterization of large size D&D waste packages: neutron measurements Example: WCAS - Waste Crate Assay System
Passive neutron multiplicity coincidence counting
High resolution isotopic gamma-ray analysis
box size up to 1660 L (1.4 x 1.4 x 1.2 m)
18% efficiency for fission neutrons
MDAs of less than 6 mg Pu-240
Evolution: adaptation of homeland security portal (detection of fuel fragments)
Example: Euritrack system (under assessment)
? Development of portable neutron assay systems
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Use of gamma camera
Acquisition Image treatment
DR (662 keV) 10 mGy/h 8.9 mGy/h
7.8 mGy/h
6.6 mGy/h
5.5 mGy/h
4.4 mGy/h
3.3 mGy/h
2.1 mGy/h
1 mGy/h
visible Dose Image rate Mode Raw levels 6270.97
3541.25
gamm Brut gamma a image Image
measurements from distance • very little manual operation Superimposition of visible • “direct” interpretation of measurements and gamma image
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Use of gamma camera
Detection of hot sptots / activity concentrations Used to improve modelling (coupling with gamma spectrometry) Planning of interventions
Examples of use of gamma camera for detection of hot spots on tanks containing liquid effluent
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 In addition: use of indoor robots
Main objective: radiation protection and security of the operators Operated owing to cameras, microphones, lights, and radiation sensors
May be equipped with dose rate probes, and even gamma spectrometry probes and gamma-camera Very radiation resistant (hardened up to 10 kGy), cable of 350 m, Wifi under development for use in reactor building (too thick concrete shielding)
Example left below: EOLE (INTRA Group, France), 1 meter lenght, 70 cm width, right picture: Russian MRK type robot (Baumann Institute, Moscow)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Site characterization before cleanup
First objective: identify hot spots, fuel fragments or pieces of activated material, to secure the area for the workers, plan cleanup work, etc.
Helicopter survey (gamma spectrometry)
Field characterization Dose rate measurement (Radball) In-situ gamma spectrometry
Portable devices Mobile laboratories
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013
Site characterization before cleanup Helicopter survey Example: HELINUC (INTRA Group, France)
On board gamma detector in a box under the Helicopter
Silmultaneous acquisition of ϫ spectrum and Helicopter position
GeHP GeHP counting time: Radionuclides NaI detector counting time: 2s 60s Cs-137 (kBq/m²) 1 6,5 0,5 Minimum Detectable Activities Eu-154 (kBq/m²) 2 10 1 K-40 (Bq/kg) 30 620 10 U-238 (Bq/kg) 10 260 20 Th-232 (Bq/kg) 3 130 13
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Helicopter survey of woods and roofs New AREVA development for Fukushima area
Unmanned helicopter equipped with automatic geolocalized measurement device REX from Chernobyl Helicopter size Low elevations Detection technology NaI probe with specific collimator GPS Currently under qualification in Japan
Expected mapping results Cs-137 Source
Unmanned helicopter during tests in Japan
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 In-Situ gamma spectrometry of soils
Soil measurements at Chernobyl site
Characterization of soil contaminated by NORM in Paris area
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Characterization of soils: use of laboratory vehicle: LAMAS (CEA, France)
Weather measurements Atmospheric measurements Wind vane, anemometer, Monitoring of radiological Beacons to measure aerosols temperature sensor, pluviometer, incidents and dose rate relative humidity Wind scattering Gas and aerosols activity Differential GPS measurements with submetric accuracy Centralization of the measures in the front cabin of the vehicle
In situ Gamma spectrometry Data processing through geostatistics
Samples treatment cell Map making Optimization of the Alpha Measurement with Perals sampling plan ‘liquid scintillation’ system Diffusion gradients
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 26 Mobile laboratory for soil/site characterization: alpha and Sr-90 measurement on samples Chemical preparation of samples
Laboratory for sample preparation, alpha measurement (U, Pu) and Sr-90: liquid scintillation counting (PERALS)
Protocols of extraction (alpha totals, U+Pu, U or Pu), for sand or ground, detection limits < 1 Bq/kg within < 24 hours. Time needed for extraction:………………………………………….5 h Counting time:…………………………………………………………8 h
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Mobile laboratories for site characterization
Mobile labs Accomodate many work conditions
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Vehicle for radiological mapping: VEGAS
Measuring devices : GPS - Gamma spectrometry GeHP, 30 % effectiveness. - NaI detector (2.4 L crystal). - Two DSP (plastic scintillation detectors) of 0,5 m² 5 cm thick
DSP
Performances at 2.5 km/h :
- Able to detect an activity >70 Bq/kg (137Cs) for 1m² soil pollution over a thickness of 5cm. - Able to detect an activity >0,37Bq/cm² (137Cs) - Able to detect a contaminated spot (137Cs) of 3800 Bq. NaI GeHP - Exhaustive measure of 0.5 ha/h.
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Monitoring of Roads Contamination AREVA recent development for Fukushima
To be used for ground areas such as roads, playgrounds, school yards, sports areas, parks, etc. Japanese Agricultural tractor with trailer Hydraulic dampers against bumps and vibrations Painting device marks contamination above threshold automatically
Detection technology used: 1m large Plastic scintillation for Contamination. GM for dose rate measurement GPS
Field Monitoring Vehicle during final tests in Minami-soma
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 In addition: use of outdoor robotic means
Outdoor robots are larger and faster than indoor robots
Can be radio-guided up to 5 km distance
Radiation hardened (less than indoor robots), resist to few tens of Gy
Equipped with manipulator(s), they can perform: Radioactivity measurements Samplings Recover active fragments Etc.
From INTRA Group (France)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Geophysics investigation for sampling
Confirm the position of drill holes by checking the absence of metallic parts or underground network near the drill holes.
Drillings with auger or Geoprobe Depends on the field, maximal depth: 2m Simple and relatively cheap anomaly Unsuitable for chemical measures Unsuitable for containment
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Characterization of contaminated soils and sites: Use of geostatistics
Geostatistics: integration of the phenomenon spatial continuity Main tool of geostatistics: the variogram => describes the variability between 2 points on average, the difference between two CLOSE measures is LOW on average, the difference between two DISTANT measures is HIGH
The way the variogram increases with distance is linked to the phenomenon spatial variability
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Geostatistics : basics
Known Data: Measurements
Data analysis
Kriging 3D Histogram
2D Interpolation 3D Interpolation (initial cartography) Experimental variogram and model (with drillings)
34
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Use of geostatistics
Interpolation Map Uncertainty Map
High variability
Uncertainty Map points out areas where there is a lack of measures or where variability is important.
98% 77% 0% 0%
May provide a risk map: Probability of 53% 10% exceeding a given activity level 46% 100% 62%
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 35 Soil sorting unit AREVA development for Fukushima Millions of tons of soil will have to be processed REX from Chernobyl accident Contamination stays within a depth 5~10 cm Contamination concentrates on localized “leopard spots”: more than half of the suspected soil is not contaminated Measurement of soil with plastic scintillator panels
Automated high-throughput sorting of soil 100 t/h Detection limit < 100 Bq/kg Mobile unit in container Feeding Output conveyors
Detectors
Testing in France before shipment to Sorting hopper the Japanese demonstration site
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Underwater measurement device AREVA development for Fukushima
ROV (Remotely Operated underwater vehicle) for lake beds inspection equipped with gamma spectrometry Capable to operate down to 200 m Measurement of sediments contamination Detection technologies
LaBr3 probe with countermeasures to handle water shielding issue Ultra Sound Baseline underwater Localization (USBL) linked to main boat and GPS aboard
3D mapping of lakes with geolocalized contamination Testing of submarine unit in data France before shipment to JAEA
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 Example of characterization applied to Legacy waste:
Characterization for the remediation of the Gremikha site
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Coastal Maintenance Base
Andreeva Bay Two former Soviet submarine bases in North-West Russia Andreeva Bay Gremikha
In the Frame of the G8 Global Partnership Against the Spread of Weapons and Materials of Mass Destruction, France decided to help Russian Federationfor funding and providing technical assistance and equipment for remediation of the Gremikha base.
CEA was leading the project assisted by AREVA
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Coastal Maintenance Base Spent Pd-Bi cooled cores
Spent nuclear VVR fuel in open air pad and in pits in building 1 Liquid radwaste (L-ILW) in underground tanks
Solid radwaste (L-ILW, HLW) In building 19
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project First step: radiological characterization of the site (soil, water basin), buildings and objects (spent fuel assemblies, liquid and solid waste) Dose rate measurements and cartography
Cesium 137 Strontium 90 Dose rate
Dose rate measurements and cartographies around the open air spent fuel storage area
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Radiological characterization of the open air spent fuel storage area
Dose rate measurements and cartography of the open air spent fuel storage area
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project 2D and 3D modeling of site contamination, water basin contamination
Soil contamination
water basin
3D modelling: better understanding of contamination spreading phenomena and its composition
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Characterization of containers with spent fuel / HLW: external dose rate, for defining intervention conditions use of robots
Dose rate measurement Dose rate measurement on a ‘sarcophagus’ containing HLW In the spent fuel storage open air area (control rod) fragments
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Characterization of casks with spent fuel / HLW: surface contamination, soil sampling, fuel fragment recovery for improving further intervention conditions use of robots
Soil sampling
Surface contamination of casks containing spent fuel and HLW
Sampling of liquid waste in casks
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Characterization of hots spots on casks containing spent fuel and high level waste using the gamma camera on a mast from 5 to 20 m height.
Site : vishka 10 v Date : 27/07/2006 Scene : Heure : 12:14:37
Coups
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0.227
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0.156
0.132
0.109
0.085
File : D:\L2ma\Gremikha\Mesures_aout06\Cartogam\10-6.scn [Image composite] Acquisition : Mode = FAIBLE COMPTAGE[28398c], 15min0sec480 (22512*0sec40), gain 9.99, jeudi 27 juillet, 2006, 12h14, Analysis : Fond : 0.0372, Max : 0.274, Contraste :86.40%, S/B :0.962, , , Fond, Débit de Dose (660 keV), 0 Gy/h Processing : seuil automatique (0.5),
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Example of characterization of hots spots on casks containing spent fuel and high level waste using gamma camera at ground level.
Gamma camera view of the open air spent fuel storage area
Hot spot detected on concrete container: characterization before its handling and further dismantling
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Characterization of casks with spent fuel / HLW: in-situ gamma spectrometry (ISOCS)
a b
Fig. 3. γ-spectrometer ISOCS with the lead-protected Ge detector during the measurements on the SRWSA: a – directed to the Bet4 container (the view from the SRWSA). b – directed down for the soil activity measurements (the view from the entrance).
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Intervention for recovery of a spent fuel fragment Localization by dose rate measurement and gamma gamera Recovery by means of robot Fragment put into an empty shielded cask
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 The Gremikha Remediation Project
Open air storage for spent fuel: cleanup of the working zone After removal of hot spots (fuel assembly fragment, control rods, etc before removal of the spent fuel casks
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013 CONCLUDING REMARKS (1)
A lot of experience feedback exists worldwide regarding characterization of: Waste from D&D waste activities Legacy waste Chernobyl accident At a lesser extent (in my opinion) NORM/TENORM waste
Some techniques / domains are or become mature for characterization purposes in case of nuclear accident: In-situ gamma spectrometry Gamma camera and coupling with dose rate measurement and gamma spectrometry Mobile laboratories Indoor and outdoor robotic means and remote controlled systems data processing: imaging, cartography for optimization of work, decision making
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013
CONCLUDING REMARKS (2)
With respect to safety of long term disposal of waste generated by a nuclear accident, efforts to be put on:
Non destructive characterization of alpha content of waste such as soils, scrap wood, plant residues, concrete rubble, etc.: portable / mobile neutron measurement systems
Address issue of long lived beta isotopes: no NDT techniques: only scaling factor method seems applicable today: method to be rended more reliable
Improvement of techniques/tools making sampling easier and more robust
Large size waste package and nuclear components (presently ramping up)
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013
THANK YOU FOR YOUR ATTENTION
TECHNICAL MEETING ON THE DISPOSAL OF LARGE VOLUME OF RADIOACTIVE WASTE, IAEA, VIENNA, 25-28 NOV. 2013