Public Control of Radiation Hazardous Facilities: Experience and Results

Independent public control of nuclear facilities is aimed at raising awareness of the general public about the effectiveness of measures to protect the environment from the radiation effects. The experience and the result of interaction between specialists of the Academy of Sciences and a higher school in organizing and conducting public control by instrumental methods of the territories for the location of radiation-hazardous facilities: uranium mining sites by underground leaching, the area of the Belarusian nuclear power plant in the pre-operational period, the area of the oating nuclear power plant "Akademik Lomonosov" and the publicly accessible territory of control area of the Mayak Production Association. Such a pooling of efforts allows for the formation of new ways of obtaining reliable information for any interested public. The results of special studies characterizing the radioecological situation in the surveyed territories are presented.


Introduction
The implementation of a number of national projects is largely due to the successful application of technologies based on radioactive substances and nuclear materials [1]. Their unique capabilities and widespread use have made them an integral part of modern world. However, the understanding of this thesis in society has not yet been established. The environmental, political, social, and economic consequences of the use of nuclear energy are of great concern and controversy among the population.
Modern organizational, engineering and technical measures to control the impact make it possible to ensure acceptable risks for humans and environmental components during normal operation of radiation hazardous facilities [2]. Further development and expansion of the use of atomic energy should not threaten the needs of future generations to preserve a favorable environment [3][4][5].
Among the key issues of sustainable development of the use of atomic energy is the problem of public acceptability of current and planned activities [6]. The population often overestimates the likelihood and severity of the consequences of possible accidents and underestimates the efforts of regulatory bodies and operating organizations to prevent or reduce radiation risks [7]. Members of the public may have subjective views on radiation risks formed under the in uence of various factors. Statements from government oversight o cials are often insu cient to increase public con dence in radiation risk assessments or measures to control such risks. The public perceives information about the development and improvement of technologies in the nuclear industry ambiguously. A number of studies have shown psychological and psychometric factors that can in uence risk perception, as well as differences between expert or technical assessment of risks versus public perception [8][9][10][11]. Inaccurate, incomplete information, objective data presented in a complex form, inaccessible to the wide public, increase mistrust in the activities of nuclear facilities and form the basis for panic, stress and protest movement. The negative public perception of the activities of nuclear facilities is reinforced by sources of information with con icting assessments of radiation risks. In such cases, the population with great con dence refers to the overestimation of the existing hazard.
To raise awareness of the population about the effects of radiation on health and the environment, complete, timely information based on facts and presented in a simple and understandable form is necessary [12,13]. Mass media, public associations and in uential persons play a signi cant role in shaping public opinion.
Educational institutions are of great importance in raising public awareness of nuclear safety and radiation protection [10]. Representatives of higher educational institutions a priori have the competence of collecting, analyzing and transmitting information in an understandable form. The participation of higher education institutions, as independent experts, in the dialogue between the public and operating organizations contributes to raising awareness and adequate perception of risks by the public concerned. One of the ways of positioning higher educational institutions as an independent party is the organization by the teaching staff and the implementation by the forces of senior students, young scientists of independent public control of the activities of radiation hazardous facilities. The operating organizations are interested in the participation of a competent, independent participant who enjoys the con dence of both the enterprise and the public.

Instruments And Methods
The methods used in the public control differ from those used by the operating organizations. Those radiation factors that are of interest to the public may not be considered by operating organizations due to negligible exposure or due to lack of reliable information. The basis for the choice of measuring instruments and procedures for instrumental control are methods of detection -in situ measurements or sampling for a more detailed examination in the laboratory.
The volume and quality of the results is signi cantly in uenced by the thoroughness of the initial data analysis and research planning, within which it is necessary to consider [14]: characteristics of existing or planned sources of releases, discharges, and radioactive waste, including the composition of radionuclides, their physical and chemical form; mechanisms of the transfer of radionuclides in natural environments, environmental features affecting the transfer, as well as their seasonal changes.
Thus, within the framework of the implemented public control programs, a methodology has been developed for conducting a pre-operational radioecological assessment of the state of the environment in the area of the NPP location, which allows: to correctly assess the impact on the environment; determine the radiation doses to the population and personnel during the operation of the NPP; determine areas and methods for monitoring the radioecological situation in the area of the NPP location; prevent erroneous interpretation of radiation monitoring data. The algorithm for conducting a pre-operational radioecological assessment of the state of the environment is shown in Fig. 1. An example of public control of a Belarusian NPP site using this algorithm is presented in [15,16].
The MKS-AT6101DR spectrometer ( Fig. 2a) with NaI(Tl) scintillation detector was chosen as the hardware for the presented approach. The MKS-AT6101DR included a data display unit, which allows visualizing the gamma radiation spectrum at the measured point of the terrain (Fig. 2b).
An automotive gamma survey using a spectrometer for radiation scanning MKS-AT6101S (Fig. 3a) or MKS AT6103 (Fig. 3b) allows to expand the survey area.

Results And Discussions
3.1 Investigations of the radioecological situation in the area of the Belarusian NPP in the pre-operational period Instrumental studies in the area of the Belarusian NPP were carried out in August 2019. During the expedition, automotive (Fig. 4) and pedestrian gamma surveys were carried out and the activity concentrations of natural radionuclides were determined, both by a non-destructive method (using the MKS-AT6101DR) and by sampling followed by measurement on a gamma spectrometer with a HPGe detector. The contribution of detected radionuclides to the dose rate on surveyed areas is presented in On the territory of the oating nuclear power plant, on the territory of Pevek and surrounding area eld spectrometric measurements on the surface of soils and coatings were carried out. The use of eld spectrometry made it possible to quickly answer the question of what radionuclides caused the external exposure of a person in the surveyed area. The identi cation of radionuclides was carried out directly at the measurement site, without sampling. At least 20 spectrometric measurements with MKS-AT6101DR were carried out on the territory of the oating nuclear power plant, urban areas, and areas remote from the city.
The performed survey did not reveal the presence of arti cial radionuclides in the surveyed areas. The dose rates on surveyed areas are presented in Table 1. The data from Chukothydromet on the dose rate in Pevek since 2013 were analyzed to con rm the correctness of the obtained results. The radiation background in Pevek, on FNPP and the surrounding grounds is completely formed by natural sources: natural radionuclides: 40 K, 226 Ra, 232 Th (Fig. 6) and cosmic radiation. The results of the expedition indicate that for two years of operation the oating nuclear power plant did not affect to the radioecological situation in the area of its location. The results of the expedition were presented at a press conference for the mass media and demonstrated for residents of Pevek at a meeting in the city administration.

Investigation of the radioecological situation in the area of uranium mining by the underground leaching method
Public radioecological control of JSC Dalur on uranium mining by in-situ leaching was carried out in September 2020. Reviewing of 42 wells was carried out in two areas differing in life cycle. The expert analysis of the pipeline system did not reveal areas with traces of technological solution leaks on the pipe surfaces or damage to vegetation in surrounding area. The instrumental control methods used in the current project included radiometric studies of production sites and surrounding areas to determine the range of dose rates characteristic of the "background" areas. MKS-AT6101DR and MKS-AT6101S were used as instruments for measuring. Radiometric studies were carried out by the method of pedestrian and automotive gamma survey. The route of the pedestrian gamma survey was chosen to obtain the dose rate values both in the production area and in the surrounding (background) area. Moving along the selected route, the operator performed a gamma scan at the mining site, a eld adjacent to the site and the nearest forest area. Field and woodland are taken as background areas. The location of the plots is shown in Fig. 7.
As a result of pedestrian gamma survey, the following data was obtained:  (Table 2).

Radiological monitoring of the publicly accessible territory of control area of the Mayak Production Association
As a result of the Kyshtym accident in 1957, more than 20,000 km 2 of the territory, later called the East Ural radioactive trace (EURT), was contaminated. The accident resulted to the release into the atmosphere of a large amount of radionuclides, including 137 Cs with the longest half-life (30.17 y). Part of the territory of EURT is included in the control zone of the Mayak Production Association. In November 2021 radiological monitoring of the publicly accessible territory of control area was conducted. The aim of the study was to determine the dose rate and the activity concentration of natural radionuclides ( 40 K, 226 Ra, 232 Th) and 137 Cs at different sites. MKS-AT6101DR was used as instrument for measurements.
The results of measurements demonstrated the presence of 137 Cs in the soil in 10 surveyed areas out of 16 (Fig. 8). The highest activity concentration of 137 Cs (about 100 Bq/kg) is observed on a forest site that was not subjected to mechanical stress, therefore, 137 Cs remained in the upper layers of the soil after releases due to accident.
The dose rate values are in the range from 0.046 to 0.121 µSv/h. The activity concentrations of natural radionuclides are: 40 K -from 27.6 to 593.0 Bq/kg, 226 Ra -from 0 to 23.7 Bq/kg, 232 Th -from 0 to 39.6 Bq/kg. Fig. 9 demonstrates the contribution of individual radionuclides to the dose rate.

Conclusion
The implemented pilot projects of public control using instrumental methods by students and young scientists are an effective way to raise public awareness of the state of the environment in the areas where nuclear facilities are located.
Public control by instrumental methods at the stage of construction of the Belarusian NPP made it possible to determine the "background" content of gamma-emitting radionuclides in individual components of the environment. The given results can serve as a basis for a radiation monitoring program, substantiation of requirements for instruments and monitoring methods, as well as for assessing risks during normal operation of the Belarusian NPP.
The results of the radioecological expedition to the area of the FNPP "Akademik Lomonosov" made it possible to present an independent assessment of the formation of radiation exposure in the city of Pevek and the adjacent territory. Objective data made it possible to answer the most important question for the residents of Chukotka about the impact of the two-year period of operation of the oating nuclear power plant on the ecology situation of the territory. The results are especially important for the indigenous population, whose diet and nutritional quality are largely determined by the conditions for the life of the local ora and fauna. Over the two years of operation, the FNPP has made it possible to signi cantly reduce environmental pollution from discharges, emissions, waste products of the operating coal red Chaunskaya TPP, and at the same time did not affect the change in the radioecological situation in the area of its location. The proposed format of interaction between higher education. the Academy of Sciences and nuclear facilities signi cantly expands the categories of participants in public control over the activities of radiation hazardous facilities. Such a pooling of efforts allows for the formation of new ways of obtaining objective information for any interested parties, including the public.
By attracting representatives of higher education and academic institutions to participate in instrumental methods of public control, operating organizations get the opportunity to use unique means and methods for measuring physical and chemical factors of environmental impact that are not included in the industrial monitoring program but are of public interest. The participation of senior students in instrumental control methods contributes to their acquisition of skills (competencies) in planning, organizing, performing goal-oriented tasks, acquaints with the speci cs of production processes of the surveyed enterprises, and expands the possibilities for a reasonable choice of place of work.

Figure 1
Algorithm for pre-operational radioecological environmental assessment  Automotive gamma survey results

Figure 5
Contribution of radionuclides to the dose rate in the area of Belarusian NPP Figure 6 Contribution of natural radionuclides to the dose rate  Contribution of radionuclides to the dose rate on surveyed areas