EPRI International Nuclear Power Plant Decommissioning Workshop
Geovariances expert in geostatistics for radiological contamination characterization Yvon Desnoyers is to present:
"Geostatistics perspectives for sampling optimization during radiological characterization"
This is the fifteenth EPRI international workshop on nuclear power reactor decommissioning. The workshop has continuously focused on the application and development of technologies in all phases of the decommissioning process.
SESSION 2: Decommissioning Characterization
Tuesday 24 October 2017 – 11:30 am
For decommissioning and dismantling projects as well as site remediation projects, a key of success lies in the characterization of the initial radiological state to better manage associated issues (waste volumes, levels of activity or exposure). Geostatistics is now regularly implemented to produce 2D/3D maps and to estimate the extent of radioactive contamination (surface and depth).
In addition, the spatial structure of radioactive contamination makes the optimization of sampling (number and position of data points) particularly relevant. Geostatistics methodology can help determine the initial mesh size and reduce estimation uncertainties (both global and local). Combining the three levels of information, namely historical context, radiation maps and destructive sampling, is also an issue geostatistics can provide useful recommendations about the total investigation effort.
The focus of this presentation is then put on feedback experience over years in the use of geostatistics and sampling optimisation for the radiological characterization of various media (soils, concrete structures, process equipment, groundwater…), various activity levels (clearance, low and intermediate, high), and various sizes from very small areas (a few m2 or a few m3) to very large sites (at a country scale in post-accidental context).