Early identification of risk connected with radioecological problems may help prevent or mitigate public and environmental risks, increase security and contribute to sustainable development of the region. Understanding of regularities and pathways of radionuclide migration will allow determining direction of processes of environmental pollution and identify sources of its origination. Hence a need arises not only in radiation monitoring of the region, but also in a system-based approach to studying transboundary pollution and radionuclide distribution in environmental compartments to ensure early warning.
The basic goal of the proposed project is developing a system of radiation monitoring of environmental (including transboundary) pollution which will allow:
- implementing environmental radiation monitoring to obtain credible and - if possible - best comprehensive information about environmental radiation status.
- predicting a change in environmental radiation situation through a dynamic model of radionuclide distribution in environmental compartments and based on radiation monitoring data and meteorological, hydro-geological etc. characteristics of the region.
Environmental radiation monitoring implies a study of radionuclide contents in environmental compartments, compartment-to-compartment transport and spatial migration of radionuclides. To this end, the project foresees sampling from different environmental compartments (soils, vegetation, atmospheric precipitation, and water basins) in the study region with consequent preparation and radioactivity analysis of samples.
Environmental radiation situation is determined both by naturally occurring (predominantly 238U and 232Th decay products) and manmade radionuclides (137Cs, 90Sr etc.). Radionuclide concentrations will be determined through gamma- spectrometric and beta-spectrometric measurements adding alpha-activity measurements. To assure credibility of results obtained when measuring samples the project plans implementation of analyses of the so-called “blind” samples, i.e. the partner institutions will exchange the samples and then collate the applied sample preparation and measurement methods and respective results obtained. Sampling will be done through unified standard methods from permanent observation points, spatial location of which will be defined with regard for meteorological, hydrogeological, landscape etc. characteristics of the region. Besides, considered will be position of potential sources of radioactive pollution. A network of observation points will be designed so that under the minimal number of observation points it could ensure the obtaining of credible and objective information characterizing radiation situation in the region.
To predict a change in radiation situation in the region the project proposes construction of a dynamic model of distribution of radionuclides in environmental compartments and their transboundary transfer. To describe time variations of radionuclide concentrations in environmental compartments balanced non-linear differential equations will be derived. A system of equations will be explored for the presence of stationary states, their stability, possibilities of analysis of oscillatory and quasi-chaotic regimes. Studied will be the influence of fluctuations of environmental parameters on radionuclide distribution in environmental compartments. The model will allow describing the dynamics of changes in radionuclide concentrations in separate compartments of the ecosystem and selecting sites to be used as indicators of a harmful increase in radionuclide contents in such components.
The model will be constructed with regard for the following pollution sources (both man-made and natural): global fallout, transboundary transport and possible pollution sources located within the study region and neighboring areas. A basis (input data) for that will be abundant experimental material (both available to the project executors and obtained in the result of the project implementation) characterizing radiation situation in the region, coefficients of radionuclide transfer from one environmental compartment to another, and a detailed survey of possible pollution sources located in the study region. Besides, the model will be constructed considering the mechanisms of entering and removal of radioactive substances: meteorological conditions, river water regime, and so on. The produced model will allow predicting a change in radiation situation and ensuring early detection of possible pollution sources (early warning).
So, the project implementation comprises the following stages:
- Analysis of available database on radiation situation,
- Data collection and analysis of meteorological conditions in the area of the study region,
- Collecting and reviewing data on hydrological balance of the region’s river basins,
- Monitoring radiation situation in the study region.
- Identifying radioactive pollution sources,
- Defining a network of observation points to implement monitoring,
- Studying mechanisms of radionuclide entering, distribution and migration in environmental compartments,
- Constructing a model of radionuclide distribution in environmental compartments,
- Predicting the dynamics of radiation situation through the constructed model,
- Setting up criteria indicating a change in transboundary transport,
The proposed project staff ensures successful achievement of the above-stated goals. The project participants have a long-standing (over 25 years) expertise in radioecological studies and have radiation monitoring data on the Armenian NPP site for 1978-2006 and other regions of Armenia - since 1958. They have impressive expertise in application of up-to-date methods of sample collection, preparation and analysis, monitoring and assessment of environmental radioactivity, and calculation of public exposure risk. The proposed project team members were trained at recognized international radiation centers and institutions and IAEA regional courses as well.
For years the team collaborated with the Institute of Biophysics USSR, Institute of Applied Geophysics (Russia), the Joint Institute of Nuclear Research (Russia) in radiation monitoring. Besides, we collaborated with Oceanology Departments of Florida and Louisiana State Universities (USA) in paleo-radioecological studies, application of radio-isotopic methods and modelling for bottom sediment dating and assessment of radioactive pollution in different time intervals. Also, we cooperated with the Institute of Radiation Problems of NAS of Azerbaijan and Tbilisi State University (Georgia) in assessment of radioactive pollution of Rivers Kura-Araks basin.
Earlier, the proposed project participants had implemeneted radiation monitoring in Armenia’s different regions and published a number of scientific articles on assessment of radiation situation in such regions including surroundings of the Armenian NPP. For the first time determined was the NPP’s direct contribution to the contents of manmade radionuclides in environmental compartments (ISTC project A-773, 2002-2005)
Besides, we were involved in ISTC projects №№ 1368, 1295, and 1605. Presently the team of the Center is being implemented ISTC projects № А-2071 and 2072 connected with liquidation of consequences of the Fukushima NPP accident. The project participants have a good expertise in international cooperation: NFSAT/CRDF project 12003 “Paleoecology and paleo-radioecology of Lake Sevan, Armenia” (2003-2004), NATO/OSCE SfP project 977991 “South Caucasus river monitoring” (2005-2006), a UNSECO project “Towards the assessment of Rivers Kura-Araks basin radioactivity”-(2006).
A technical approach and methodology for the proposed researches consist in combination of numerous experimental methods (spectrometric, radiometric, radiochemical, etc.) with theoretical modeling (both analytical and numerical). The aforesaid method will enable the project executors to generate an unambiguous opinion about radiation situation in the study region, mechanisms of radionuclide distribution and migration in the environment and in the case of transboundary pollution. The project results will provide basic information to
- Organizations dealing with radioecology researches,
- Ministry of Ecology,
- Ministry of Healthcare,
- Ministry of Agriculture,
- Department of Emergency Situations,
- Nuclear regulatory bodies,
- Regional and local self-governance bodies,
- Organizations of agricultural profile.
