12. CONCLUSION

The materials, presented in the overview, allow one to get a general idea of the scale and complexity of the problems of the radiation legacy of ex-USSR.

The materials' analysis shows that the organizations, taking part in the Project's works, possess large volumes of data in particular sectors of investigations. However, some data still remain secret. This has led to the non-uniformity of individual chapters' data in completeness of problem descriptions.

The reviews on nuclear power plants, marine nuclear power installations and enterprises for their repair and maintainment, sea dumping of radioactive wastes, radiation consequences of nuclear weapon tests and some others in the highest degree meet the overview task. At the same time on nuclear fuel cycle enterprises, research nuclear reactors, geological disposal of radioactive wastes and reviews on accompanying problems are less complete.

Among the Overview's general drawbacks the following ones should be listed:

• non-uniformity of the data time presentation, which in conditions of ever - changing situation at objects sources of radiation hazard, makes more complicated the estimation of the risk level for biosphere due to effect of one or another group of objects at a given moments;
• absence of a well defined set of still inaccessible data, which are of importance from the point of view of the Project tasks as well as considerations concerning ways of getting the data in the future;
• incomplete presentation of results of the work carried out in Russia accounting for sites of storage and disposal of radioactive wastes.

The above mentioned and other disadvantages to a degree are a consequence of objective causes. conditioned by a huge amount of information, inaccessibility of some important data, absence of experience of work with large flows of information, as well as limited financial resources.

Nevertheless, the materials presented in the overview, make it possible to define on the whole the set of the main potentially hazardous objects in Russia. They may in case of occurring emergency situations (earthquakes, floods, etc), turn out to be the main sources of radiation contamination of the biosphere. Among such objects the following ones can be named:

• objects, situated in Northern and Pacific regions of Russia (Murmansk and Arkhangelsk Regions, Primorsk Land), connected with providing operation and utilization of the Navy nuclear submarines and civil nuclear powered ships;
• some objects of the Industrial Association "Mayak" in Chelyabinsk Region (Karachai Lake, the cascade of water reservoirs);
• the surface reservoirs - storages of liquid radioactive wastes at the Siberian Chemical Combine in Tomsk Region and at the Mining & Chemical Combine in Krasnoyarsk Land;
• the storehouses of spent nuclear fuel and radioactive wastes at NPPs, first of all, at NPPs with RBMK reactors;
• the storehouses of radioactive wastes at special enterprises of "Radon" type in different regions of Russia.

These objects are today the subject of public anxiety in the above mentioned regions of Russia.

As to the sites of deep underground disposal of liquid RW in Krasnoyarsk-26, Tomsk-7 and Dimitrovgrad, according to conclusions of experts of the Minatom of Russia, as well as of a number of institutions of the Russian Academy of Sciences and other departments, they are not hazardous to the environment and the population in any accident situations. However, the RW contain long-lived radionuclides, and many hundreds of years are needed for their full decay. That is why permanent thorough control for the disposal sites is necessary, as well as conducting of additional investigations.

It should be noted, that the possibility of using such a method of RW disposal is limited, because it requires presence of suitable geological structures.

In the framework of further development of works on the Project "RADLEG" it seems worthwhile:

• to continue the improvement and verification of data in each sector of investigation by the organizations participanting in the Project with stage by stage transition to particular sites and objects;
• to provide permanent input of data, keeping in mind to also bring in previously inaccessible data as soon as they are available;
• to carry out for two or three of the most potentially hazardous objects ranking of risks, connected with the radiation legacy both in local and global scale, - to evaluate measures to lower risk including the preliminary cost analysis;
• to continue works on creation of the accessible database, connected with a geographical information system, presenting available data on radiation legacy of ex-USSR.

The "Radleg" Project aimed at development of a complex information system for evaluation of the radiation legacy of the ex-USSR and setting priorities in environmental policy and preventing the radiation contamination of the biosphere is included in the list of priority projects on radioactive wastes management in Russian Federation (Supplement)

On the whole the analytical overview is a first important stage on the way of objective evaluation of the scale of the former USSR radiation legacy. The Overview's materials may serve as initial data for further development of works in the frames of the "RADLEG" Project and other similar projects.