TRITIUM - A Quasi Real-Time Low Activity Tritium Monitor for Water

Instituto de Física Corpuscular (IFIC)

M. Martínez-Roig(corresponding author), T. Cámara, V. Delgado, J. Díaz, N. Yahlali are with Instituto de Física Corpuscular, Centro mixto CSIC-Universidad de Valencia, Paterna, Spain. (e-mail: marcos.martinez@ific.uv.es)
C.D.R. Azevedo, is with I3N - Departamento de Fisica da Universidade de Aveiro, Aveiro, Portugal
M. Brás is with I3N - Departamento de Fisica da Universidade de Aveiro, Aveiro, Portugal
J.F.C.A. Veloso is with I3N - Departamento de Fisica da Universidade de Aveiro, Aveiro, Portugal
C. Roldán is with Universidad de Valencia, Departamento de Física Aplicada, Burjassot, Spain.
A. Baeza, is with Universidad de Extremadura, Laboratorio de Radioactividad Ambiental. Servicio de apoyo a la investigación, Cáceres, Spain
J.A. Corbacho is with Universidad de Extremadura, Laboratorio de Radioactividad Ambiental. Servicio de apoyo a la investigación, Cáceres, Spain
A. Rodríguez is with Universidad de Extremadura, Laboratorio de Radioactividad Ambiental. Servicio de apoyo a la investigación, Cáceres, Spain
C. Cerna is with Université de Bordeaux and CNRS, CENBG, Gradignan Cedex, France.
E. Chauveau is with Université de Bordeaux and CNRS, CENBG, Gradignan Cedex, France.
J. Domange is with Université de Bordeaux and CNRS, CENBG, Gradignan Cedex, France.
C. Marquet is with Université de Bordeaux and CNRS, CENBG, Gradignan Cedex, France.
F. Piquemal is with Université de Bordeaux and CNRS, CENBG, Gradignan Cedex, France.
J.M. Gil, is with Junta de Extremadura, Plaza del Rastro s/n. 06800, Mérida, Spain.
A. Moreno is with Junta de Extremadura, Plaza del Rastro s/n. 06800, Mérida, Spain.
J. Rodríguez is with Junta de Extremadura, Plaza del Rastro s/n. 06800, Mérida, Spain.

Published online: 20 January 2020

Abstract

Tritium is released abundantly to the environment by nuclear power plants (NPP), as a product of neutron capture by hydrogen and deuterium. In normal running conditions, released cooling waters may contain levels of tritium close to or even larger than the maximum authorised limit for human consumption (drinking and irrigation). The European Council Directive 2013/51/Euratom requires a maximum level of tritium in water for human consumption lower than 100 Bq=L. Current monitoring of tritium activity in water by liquid scintillating method takes about two days and can only be carried out in a dedicated laboratory. This system is not appropriate for real time monitoring. At present, there exists no available detector device with enough sensitivity to monitor waters for human consumption with high enough sensitivity. The goal of the TRITIUM project is to build a tritium monitor capable to measure tritium activities with detection limit close to 100Bq=L, using instrumentation technique developed in recent years for Nuclear and Particle Physics, such as scintillating fibres and silicon photomultipliers (SiPM). In this paper the current status of the TRITIUM project is presented and he results of first prototypes are discussed. A detector system based on scintillating fibers read out either photomultiplier tubes (PMTs) or silicon photomultiplier (SiPM) arrays is under development and will be installed in the vicinity of Almaraz nuclear power plant (Cáceres, Spain) by the fourth term of 2019.