Francisco Javier Guillén Gerada LARUEX, University of ...
Transcript of Francisco Javier Guillén Gerada LARUEX, University of ...
SAMPLING:
Objective: Detection limit / A ± σ Sample size
What: Source term: monitoring nuclear installation, accident scenario,
NORM, etc.
Gaseous
effluents
Liquid
effluents
External γ
Dose rate
Where:
• Define sampling points
• Vicinities source term
• Water courses, reservoirs, …
• Sampling stations (permits)
• In situ
• Laboratory
Locations Analysis
Transportation
Sample preservation
When: • Real time, daily, weekly, monthly, biannual, annual, …
• Composite simple
How: • ISO/IEC 17025 defines technical competence, including sampling
• Sampling procedures must be written, tested and followed
• Everything must be considered previously
to sampling
• Any choice taken during sampling may affect
the result
Almaraz NPP
Environmental Radioactivity Surveillance Network around Almaraz NPP
• Real time monitoring stations
• Sampling programmes
• Quality control for NPP’s Environmental Radioactivity Progamme
Soil sampling:
Depth:
• Radionuclide deposition: surface soil (0-3 cm, 0-5 cm, …)
• Research: depth profile, 0-10 cm, …
Envelope or W scheme
2 m
2 m
Record coordinates
Flat area, away from tree cover
Before sampling: removing grass, litter, etc.
Sample preparation:
• Sieve through 2 mm sieve
• Ball mill to homogenize simple
• But, any particles?
Water sampling:
Drinking water Surface water, groundwater Rainwater
Use clean containers
It dependsNo filtration
Screening
Pore size: 0.45 μm
Sample preservation prior to analysis:What radionuclide is of interest?
In situ or back in the lab?
Does it require filtration?
Refrigeration AcidificationSpecial considerations:
Tritium
Iodine
Radon
Sediment sampling:
Shore sediment
Collected about 2 m from shore
Deep sediment
Special requirements: boat
Foodchain sampling:• Self production
• Buy from local producers
Transportation: different requirements depending on simple type
Refrigeration
Iodine
Refrigerated or NaOH
Aerosol sampling:
Low volume High volume
Sampling station: days, weeksPortable collector: hours
Particulate fracction: which filter?• Pore size: 0.8 μm, 0.45 μm, …
• Material: fiberglass, cellulose, petrianov, …
• Size: pumping head
Gaseous fraction: Atmospheric tritium collector
Bubblers with:
Water
Ethylenglicol
Automatic alert system in quasi-real-time, with a customsoftware package for the management of radiological,meteorological and operational parameters.
17 RARE air monitoring stations
+3 RARE water
monitoring stations
+2 CSN air monitoring
stations
1 mobile laboratory
2 drones (under development)
Gamma dose rate external monitoring stations
Geiger-Müllerdetector
1 parameter
5 parameters
1 parameter
H*10
LB 6361 (Berthold)
Sensitive range: 0,040 uSv/h – 20 mSv/h
Energy range: 80 kev-1.3 MeV
Gammatracer-XL and XL2 (Saphymo)
Sensitive range: 0.020 or 0.010 uSv/h – 10 Sv/h
Energy range: 45 keV – 3 MeV
Quality guarantees:
ISO 9001:2015 certification
ISO/IEC 17025:2008 accreditation
Monitoring frequency:
3-10 minutes
H*10 (μSv/h)
RARE-CSN-EURDEP
Transmission modalities to RARE´s headquarter:• Intranet• Analogical radio• Digital radio (4RF)• 3G(At least, two are available per monitoring station)
Alarm levels:Level 1: 30% of monthly average dose rate plus annual average dose rate fromnatural background.Level 2: 0.114 μSv·h–1 plus annual average dose rate from natural background.Level 3: 0.228 μSv·h–1 plus annual average dose rate from natural background.
Airborne monitoring stations
Bertholdsystem
5 parameters
2 parameters
Air conditioning
system
5 parameters
12 parameters
RAREsystem
5 parameters
17 parameters
H*10 + a, b, 222Rn and 131I
H*10 + radioisotopes activities
Water monitoring stations
Vessel volume: 25 L
Water flow: 40L/min
Measurement frequency: 10 min
Automatic extra sampler for additional
laboratory analysis: 15L
5 parameters6 parameters
15 parameters