Development of ‘on-site’ measurement methods for assay of alpha - emitting radionuclides

SCK•CEN Mentor

Vasile Mirela, mvasile@sckcen.be, +32 (0)14 33 28 31

Expert group

Low-level Radioactivity Measurements

SCK•CEN Co-mentor

Verrezen Freddy, fverreze@sckcen.be, +32 (0)14 33 28 76

Introduction

A fast response in case of a nuclear accident or characterization of contaminated sites is very important. In this case, the use of mobile laboratories on site is the most suitable approach. A general tendency is being observed where such technology and/or approach is being applied or developed (e.g. SMaRT developed by CEA, France (Goudeau et al., 2017)). Since these methods are expected to be cheap (compared to transport of samples and analyses in off-site laboratories), they generally will have a higher probability to be applied when cost is an issue. The methods that are proposed are generally less complicated than their counterparts in the routine laboratories, but also have lower accuracy.  Such methods however may give basic information about unknown samples allowing faster decisions on the need for more detailed analyses and avoiding unnecessary expensive analyses.

Objective

Development of fast analytical procedures capable of giving a response with respect to the type of contamination - alpha - emitting radionuclides (such U, Pu, Th, Cm isotopes) and taking into account the specific requirements for rapid measurements (i.e. accuracy, detection limit, throughput time, waste management, etc.) = fit-for-purpose.

To obtain sample material appropriate for alpha spectrometry, leaching is proposed. A first step will be to set-up leaching experiments using spiked soil and plant material. Different parameters will be investigated in order to obtain a good recovery of the tracers used in the spiking (such as mixing time, molar concentration of the acid, type of the acid, etc.).

Second step consists in investigating the separation and source preparation procedures and their compatibility with the field conditions.

Third step is related to the investigation of the measurement equipment and the way that this can be made available in the field (e.g. design of the set-up).

These methods are meant to be used in an ‘on-site’ measurement laboratory or intervention vehicle for alpha emitter radionuclides using validated working procedures. Initial experimental tests will be performed in our laboratories using existing equipment (alpha-particle spectrometry).

References

1. Goudeau,V. et al., 2017. Mobile laboratories: An innovative and efficient solution for radiological characterization of sites under or after decommissioning. Journal of Environmental Radioactivity, https://doi.org/10.1016/j.jenvrad.2017.04.010.

The minimum diploma level of the candidate needs to be

Academic bachelor

The candidate needs to have a background in

Chemistry