ASN Report 2020

This monitoring is based on: ∙ continuous on-site monitoring using independent systems (remote-monitoring networks) providing real-time transmission of results. This includes: ‒ the Téléray network (ambient gamma radioactivity in the air) which uses a system of continuous measurement monitors around the whole country. The density of this network is being increased around nuclear sites within a radius of 10 to 30 kilometres around BNIs; ‒ the Hydrotéléray network (monitoring of the main water­ courses downstream of all nuclear facilities and before they cross national boundaries); ∙ continuous sampling networks with laboratory measurement, for example the atmospheric aerosols radioactivity monitoring network; ∙ processing and measurement in a laboratory of samples taken from the various compartments of the environment, whether or not close to facilities liable to discharge radionuclides. ENVIRONMENTAL MONITORING DURING THE LOCKDOWN The Basic Nuclear Installation (BNI) licensees perform the regulation monitoring of the environment around their sites, in accordance with the requirements of the ASN resolutions governing water intake and consumption, the discharge of gaseous and/or liquid effluents and environmental monitoring around the facilities. As a result of the Covid-19 health crisis, during the lockdown in Spring 2020, some licensees had to temporarily adapt their regulation environmental monitoring programme to the activity continuity plans implemented. These modifications or compensatory measures were monitored by ASN throughout the lockdown period by means of regular meetings with the various licensees. They for example concerned bringing back in-house certain tasks that were usually subcontracted, relaxing the frequency or prioritisation of certain samples and/or analyses. Similarly, ASN granted a few days grace for the transmission of regulation documents, such as the monthly registers, to ensure that the information they contained was exhaustive. This lockdown period also accelerated the process to implement the dematerialisation of certain procedures, such as approval prior to certain effluent management operations provided for in the resolutions issued by ASN. During the second lockdown in the Autumn of 2020, the licensees mentioned no particular difficulties and maintained their environmental monitoring programme in accordance with the above-mentioned resolutions. THE IMPACT OF COVID-19 Summary of knowledge acquired 10 years after the publication of the Tritium White Paper In 2020, ASN published the TritiumWhite Paper , presenting the state of scientific knowledge on the presence and sources of tritium in the environment, as well as the environmental and health impact of this radionuclide. It also included recommendations from two pluralistic think tanks, along with the resulting action plan. Ten years after this White Paper was published, in 2020, ASN published the summary of the knowledge acquired in the fields studied. Knowledge concerning metrology, control of discharges, environmental monitoring and assessment of the impact of tritium on human health has progressed, providing answers to the questions raised by ASN, even if some actions still have to be finalised. The metrological advances include the drafting of several standards for measuring tritium in the matrices of the environment and effluent discharges, as well as the adoption of inter-laboratory comparison tests. Research into tritium transfer and its activity level in the environment has been carried out. Understanding of the toxicity of tritium has also progressed, notably by showing that the effects of tritium at concentration levels close to those found in the environment remain extremely limited. At higher concentration levels that can be encountered in the effluents produced by the facilities, biological effects that differ according to the physical-chemical forms of tritium are observed, which underlines the importance of differentiating between them in the discharges from facilities so that the corresponding risks can be characterised. The studies performed revealed the prevalence of the “free” form of tritium in discharges from the facilities, confirming the low corresponding impact. The inventory of tritium discharges from the Basic Nuclear Installations (BNIs) and Defence Basic Nuclear Installations (DBNI) as well as the balance of the corresponding dosimetric impacts are published yearly by ASN on the TritiumWhite Paper website. Given the tangible improvements in knowledge, in particular concerning metrology and characterisation of the physical-chemical forms of tritium in discharges, ASN closed the work of the tritium action plan oversight committee in 2020. Oversight of the research work still in progress, notably on the subject of the biological effects of tritium and the corresponding health hazards, will now take place in a different format, for example during special research seminars or days. ASN thus asked the French Institute for Radiation Protection and Nuclear Safety (IRSN) to organise a “research” day in the first half of 2021 devoted to this subject and to invite the parties concerned, notably the members of the tritium action plan oversight committee. At the same time, in conjunction with the IRSN, ASN is closely monitoring a tritiummeasurement campaign in the Loire which was started in November 2020, with the aim of improving knowledge of the dispersal conditions for the tritium discharged into the environment by the Nuclear Power Plants (NPPs) on the Loire and Vienne rivers. The results of this study will be published during the course of 2021. ASN Report on the state of nuclear safety and radiation protection in France in 2020 165 03 – REGULATION OF NUCLEAR ACTIVITIES AND EXPOSURE TO IONISING RADIATION 03