Chernobyl International Polygon for Radiation Protection Research

Nuclear reaction, radiation and radioactive materials are used extensively in generation of energy, medicine and industry. Radiation protection, priority of EURATOM 6^th Framework Programme (FP6) for Nuclear Research and Training Activities, is the key for safety in that area. The real and effective researches on radiation protection need a real polygons and infrastructure.

On 26 April 1986, the most serious accident in the history of the nuclear industry occurred at Unit 4 of the Chernobyl nuclear power plant in the former Ukrainian Republic of the Union of Soviet Socialist Republics. The reactor was destroyed and large quantities of radioactive material were released into the environment. The total activity of all the radioactive matter released in the accident is today estimated to have been around 1.2 x 10¹⁹ Bq.

The Exclusion Zone around the Chernobyl NPP (hereinafter Exclusion Zone) is the area most contaminated by the accident. Its population was evacuated outside the area in 1986, and all economic activity not related to the Chernobyl NPP (ChNPP) was stopped. The Exclusion Zone covers a surface area of 4300 km².

At present, the main radionuclides causing Exclusion Zone contamination are ¹³⁷Сs, ⁹⁰Sr and a -emitters of transuranium elements (TUE) ^{238, 239, 240}Pu, ²⁴¹Am. The amounts of the radionuclides deposited in the Exclusion Zone (on the ground surface) are about 11PBq.

During about 20 years after accident by international scientists have been collected unique data on radiation protection, radioactive waste management, and nuclear safety.

The polygons for radionuclides migration into environment have been deployed and data are collecting since 1986. Unique medicine data on an exposed people have been collected.

Chernobyl Exclusion Zone polygons, collected data base could be defined as a large infrastructure- Chernobyl International Polygon (ChIP), which could provide for European scientists unique research capabilities on radiation protection.

5 research areas in which ChIP has capability for international research are defined:

¨ Radionuclides migration into the environment

¨ Investigation and modelling of radionuclides transfer from soil to the plants.

¨ Post-accidental radiological risk governance, developing of modern techniques and procedures off-site emergency monitoring.

¨ Epidemiological studies of suitable exposed populations for better quantify and understand the risks associated with low and protracted exposures to ionising radiation

¨ Radiation protection legislation in the case nuclear accident

The western partners have high interest to use unique Chernobyl polygon and expertise for international research on radiation protection and have capability to assess to unique ChIP infrastructure.

Scientists and students will have opportunity to come and doing joint research on Chernobyl Polygon. ChIP will provide for them scientific support, instruments, transport, assistance for sampling, access to data base, accommodation, cover transport expense, etc

International Scientific Council of ChIP will define certain subjects and program for each researcher. Participated universities will programming visits 4-6 scientists or/and students to Chernobyl for collecting data (for instant, to collect samples, to prepare samples, to make measurements of the samples radioactivity, to study data base of victim people health monitoring, etc.)

Infrastructure staff will assist in developing of research programs and field exercise, consultation in data base using, provide appropriate equipment, facilities and transport, lodging, etc.

Research programs and results will be published on our web site tesec-int.org and will be open for other possible participants.

Background of International Research in the Chernobyl Exclusion Zone

Subjects for international collaboration in 2005-2007

Logistics approach

Background of International Research in the Chernobyl Exclusion Zone

During about 20 years after accident by international scientists have been collected unique data on radiation protection, radioactive waste management, and nuclear safety.

Within the EC projects have been carried out comprehensive research in different radiation protection areas:

- Long-term effects of damage in persons exposed to a radioactively contaminated environment, 2003, INCO

- Chernobyl, an integrated pan-European study : morphology, oncogenes, DNA repair and outcome in radiation carcinogenesis, 2003, FP5-EAECTP

- Radioecological study of the Chernobyl Cooling Pond and options for remediation, 2002, INTAS

- A long-term follow up study of a cohort of highly irradiated victims of the Chernobyl accident to improve dose assessment for past exposures by analysing changes in the yields of stable and unstable chromosomal aberrations, 2002, INTAS

- Doses to the Belarus and Ukraine populations resulting from the Chernobyl accident, 2002, INCO

- Radioactivity environmental monitoring (REM), 2002, FP5-JRC .

- Genetic and environmental factors influencing the risk of radiation induced thyroid cancer following the Chernobyl accident, 2002, INCO

- Radionuclide contamination of soils and groundwater at lake Karachai waste disposal site (Russia) and the Chernobyl accident site (Ukraine) : field analysis and modeling study, 2001, INCO

- Long erm environmental behaviour of radionuclides, 1999, NFS 2

- Redisttribution of Chernobyl Radionuclides in River Basins: Environmental and Geomorphological Perspectives, 1997, INTAS

- Modelling and study of the mechanisms of the transfer of radioactive material from terrestrial ecosystem to and in water bodies around Chernobyl, 1995,COSU C

The polygons for radionuclides migration into environment have been deployed and data are collecting since 1986. Unique medicine data on an exposed people have been collected.

Chernobyl Exclusion Zone polygons, collected data base and expertise is large infrastructure- Chernobyl International Polygon (ChIP), which could provide for European scientists unique research capabilities on radiation protection.

Radionuclides migration into the environment, investigation and modelling of radionuclides transfer from soil to the plants

Many countries need to use unique ChIP facility for developing and testing national procedures for radiological monitoring.

Assessment of the Chernobyl Exclusion Zone’s barrier function, its reliability, the natural recovery processes and validation of possible additional protection measures and their implementation is an important combined task of ongoing and future national and international scientific research and applied programmes.

In the frame of Franco-German Initiative for Chernobyl, a specific subproject was dedicated to countermeasures in agricultural and natural environment and their efficiency. The efficiency of the main countermeasures in agricultural production is assessed on the radioecological aspect.

There are researches directed to improvement of fundamental knowledge on interaction of contamination with different natural barriers and processes for radionuclides migration through the geological environment.

Anomalously high mass-exchange between near-surface layers (atmosphere, biological complex, soil cover, rocks in the aeration zone) and deep geological deposits (sedimentary cover and crystalline basement) was revealed based on results of performed investigation of landscapes developed in the micro-geodynamic zones in the closed depressed forms of microrelief (depression morphosculptures). Structural peculiarities of their external elements and deep layers, regularities of their formation and development, dominating processes at certain evolution stages were determined, as well as impact of given natural specific formations on the redistribution of liquid and solid phases in surface runoff studied.

Basic methodical principles of investigation and theoretical substantiation of micro-geodynamic zones development were created, as well as integral assessment performed of radiocontamination redistribution in different types of microlandscapes determined by geological micro-structure.

Post-accidental radiological risk governance, developing of modern techniques and procedures off-site emergency monitoring

Another area of radiation protection is developing of better approaches for risk governance and more effective and coherent off-site emergency management in Europe, including the rehabilitation of contaminated areas. Each years since 1997 European Center of Technological Safety (part of ChIP) carrying out International Summer School for developing and testing procedures for monitoring during a Nuclear or other Radiological Emergency. Procedures for air, soil, water, plant samples collecting and measurement have been developed and testing on unique real contaminated area in Chernobyl Exclusion Zone.

The soil profiles from a meadow of the Chernobyl area were investigated for hot particles. Three types of particles were identified: (1) particles with high ¹⁵⁴Eu, ⁹⁰Sr / ¹³⁷Cs ratios, i. e. fuel particles; (2) with low ratios, i. e. condensed type particles, and (3), particles containing ⁶⁰Co, probably fragments of activated structural material attached to fuel particles. Among fuel particles, those ejected during the initial explosion and those released during the reactor fire can be distinguished again by the Eu/Cs ratio. The maximum migration depth in soil of the particles 15 years after deposition is more than 10 cm, which results in a maximum migration rate of 0.7 cm/a.

In 1999 jointly with IAEA have been organised workshop intercomparison measurement exercise in the Exclusion zone arround Chernobyl NPP where mobile teams tested the generic procedures from IAEA-TECDOC-1092. In 2002 such Summer School have been orginized within INTAS-Ysschool 01-6/5 project.

Epidemiological studies of suitable exposed populations for better quantify and understand the risks associated with low and protracted exposures to ionising radiation

Many western universities carrying out research on radiation protection, specifically effects of the low dose exposure, but such researches need contingent of people, which have been exposed. Many thousand people in Ukraine had been exposed in result of Chernobyl accident. That people are under the medical monitoring since 1986, by scientists of Ukrainian Centre of Radiation Medicine, which is part of ChIP. ChIP will provide unique opportunity for western scientists on epidemiological studies of suitable exposed populations, and on cellular and molecular biology research on the interaction between radiation and the DNA, cells, organs and the body.

As a result of accident consequences studying, deterministic effects caused by radiation exposure and intensified by other accident factors (burns) have been observed. The early radiation effects led to the development of acute radiation syndrome (ARS) in 134 victims, whose radiation dose varied from 1 to 12 Gy. Of these, 28 died within the first three months as a result of combined radiation and non-radiation injuries, and another 14 in subsequent years. The 92 ARS convalescents constitute a priority medical observation group and, in order to minimize the delayed stochastic effects, should be given all the necessary medication, diagnostic and medical services for the rest of their lives.

Regarding the stochastic effects in humans caused by the ionizing radiation which is characteristic for the Chernobyl accident, the following conclusions and recommendations have been made:

- the dramatic increase in radiation-induced thyroid cancers in children and adolescents in Belarus, Russia and Ukraine, which has been observed since 1991, continues to this day. Further thyroid cancer cases are expected in the coming decade in persons who were exposed as children and also in the clean-up workers of the accident in 1986. To minimize the effects of thyroid cancer among the exposed population and the clean-up workers, measures aimed at timely detection and treatment of these cases should be implemented;

- the possible increase noted in the incidence of leukaemia above the spontaneous level in the Russian clean-up workers and the fact that there is no increase in the incidence of leukaemia among the adult and child population living in the contaminated areas of the three States should be the subject of further standardized epidemiological studies. It is especially important that all diagnoses of leukaemia be confirmed by an international team of haematologists;

Health effects of the consequences of the accident have been observed in clean-up workers and the population of contaminated areas for which the radiation dose effect relationship has not been established. Further studies are necessary to include other possible causes, such as, psychological and social consequences, ageing and the effect of screening, so as to identify their relevance to the following data:

- the progressive deterioration in the health of the 1986-1987 clean-up workers in the three countries;

- for a number of non-oncological diseases (diseases of the endocrine system, cardiovascular diseases, psychoneurotic disorders, etc.), the morbidity indexes among the clean-up workers, the population living in the contaminated areas and evacuees from the Exclusion Zone statistically significantly exceed the national averages for all citizens.

Investigations of the effects of radiation on biota in the Chernobyl Exclusion Zone have shown an increase in the frequency of radiation-induced chromosomal aberrations. Also, various genetic effects of chronic exposure have been reported. It would be useful to stimulate research into the radiological effects of small doses on biota and ecosystems, ensuring thorough dose monitoring.

Subjects for international collaboration in 2005-2007

For nowadays by the International Scientific Council have been defined certain subjects for international collaboration, which presented in table 1.

Table 1

	*Subject*
1	Radionuclides migration into the environment
1.1	Radionuclides atmospheric deposition processes
1.2	Migration of radionuclides due to runoff
1.3	Vertical and horizontal migration of radionuclides
1.4	Radionuclides transfer to foodstuffs products
1.5	Transport of radionuclides by rivers, including remobilisation by sediments, impact of flood events
1.6	Inventory and fluxes of radionuclides in large catchments basin
1.7	Radioecotoxicity
1.8	Radiological sensitivity
2	Post-accidental radiological risk governance, developing of modern techniques and procedures off-site emergency monitoring.
2.1	Developing in -situ gamma spectrometry
2.2	Management of the post accidental situation, development of post accidental radiation protection technical assistance software :
2.2.1	Prediction of transfer to foodstuff products
2.2.2	Contamination maping, reduction of uncertainties
2.2.3	Data base management
2.2.4	Development of radioecological models
2.2.5	Post accidental survey
3.	Radiation protection legislation in the case nuclear accident
3.1	Application of ALARA principle on contaminated area after nuclear accident.
3.2	Comparative analysis of Chernobyl legislation with requests of international legislation.
3.3	Implementation of Vienna convention on international assistance and early notification in a case of nuclear accident
3.4	Insurance of risky team involved in the intervention in case of nuclear accident.

Logistics approach

The international scientific community is invited for collaboration on that subjects.

Following the interinstitutional agreement ChIP will use resources (data-base, equipment, manpower, etc.) of:

European Centre of Technological Safety

Ukrainian Centre of Radiation Medicine

Radio-Environmental Centre, National Academy of Science of Ukraine

other research institution in Ukraine.

International Scientific Council of ChIP consists of western and eastern key scientists will define certain subjects and program for each researcher. Participated universities will programming visits 6-10 scientists or/and students to Chernobyl for collecting data (for instant, to collect samples, to prepare samples, to make measurements of the samples radioactivity, to study data base of victim people health monitoring, etc.)

Infrastructure staff will assist in developing of research programs and field exercise, consultation in data base using, provide appropriate equipment, facilities and transport, lodging, etc.

Research programs and results will be published on our existing web site tesec-int.org and will be open for other possible participants.