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The methods and means for performing a radiation survey of objects and grounds of the Kirovo-Chepetsk Chemical Combine are presented. Results of a survey of rooms in the combine and measurements of soil contamination levels on the grounds and of the specific activity of samples of radioactive wastes in temporary repositories and slag dumps are presented. The surveys make it possible to develop a concept and a project for rehabilitating these objects and grounds and to choose a technology for handling radioactive wastes during liquidation or preservation of repositories.In 2007-2008, specialists from the Russian Science Center Kurchatov Institute, Moscow Scientific and Industrial Association Radon, and the Center for the Administration of Federal Property examined radioactively contaminated objects and grounds of the Kirovo-Chepetsk Chemical Combine in order to collect data on the contamination of buildings, where work on the reprocessing of uranium raw material was terminated, as well as sludge and radwaste repositories. At the same time, it was discovered that individual areas on the grounds of the combine were radioactively contaminated as a result of the handling of radwastes as well as the presence of equipment contaminated at the early stages of the development of the technology for reprocessing uranium hexa-and tetrafluoride. In addition, it was necessary to determine the volumes of remediation work, identify the most critical objects and grounds, and develop remediation steps. Models of radionuclide migration in environmental objects and forecasts of radionuclide propagation in the next few years will be developed on the basis of these data.Basic Reasons for the Radioactive Contamination of Objects and Grounds. The Kirovo-Chepetsk Chemical Combine is located on the western edge of the town of Kirovo-Chepetsk. The production of uranium hexafluoride was set up there in the 1940s. Facility No. 93 for the production of uranium tetrafluoride was started up there in 1954 and reached its full production capacity in 1955. Initially, it was assumed that this facility would use secondary uranium which had been irradiated in a reactor. After the irradiated uranium was dissolved and the plutonium and most of the fission products in the form of uranyl-sodium diacetate salt had been removed from it, the irradiated uranium entered facility No. 93 for reprocessing into uranium tetrafluoride and then into facility No. 2 for the production of uranium hexafluoride [1]. In 1961, specialists at the combine and at the All-Russia Research Institute of Chemical Technology (VNIIKhT) developed a technology for repro-

The results of an examination of objects and grounds of the Kirovo-Chepetsk Chemical Works are presented. The methods used to perform a radiation survey are described briefly. The data obtained are used as a basis for a concept of rehabilitation of radioactively contaminated objects and grounds of the works. The radwaste volumes are determined for each object and possible ways to handle them are proposed. The technologies for handling radwastes are examined. The primary problems that must be solved without delay are determined.The work performed at enterprises brought into the development of technological solutions and the commercial production at the initial stage of the development of chemical technologies for the nuclear industry, both in the past and at present, results in radioactive contamination of grounds and other ecological problems. One such enterprise is the Kirovo-Chepetsk Chemical Works, which was privatized at the beginning of the 1990s and ignored by Rosatom for many years. In 2004, the radiologically dangerous objects and workshops, previously associated with the reprocessing of uranium raw materials, were reverted to state ownership and put on the books of the Center for Federal Property Management.In 2007-2008, specialists from the Russian Science Center Kurchatov Institute, Alliance-Gamma company, and the Center for Federal Property Management examined the radioactively contaminated objects and grounds of the Works in order to develop principles and methods for rehabilitating buildings and objects holding stopped facilities for reprocessing uranium raw materials as well as storage sites for sludge and radwastes. Aside from this, previous surveys of the site and zones containing waste repositories revealed radioactive contamination of separate grounds, which was due to the handling of wastes and equipment contaminated at early stages of the development of the technologies for reprocessing uranium hexaand tetrafluoride [1]. The survey made it possible to assess the volumes of rehabilitation work, determine the most critical objects and grounds of the Kirovo-Chepetsk Chemical Works, develop the order in which measures should be implemented to decrease the radiological risk to the general public and the environment.Contaminated Grounds and Objects of the Works. Approximately 70 ha of grounds located on the site of the polymer plant (13 ha), in the sanitary-protected zone (19 ha), and the observation zone (38 ha) were contaminated during the period

Possible ways to rehabilitate the objects and grounds of the Kirovo-Chepetsk Chemical Works are examined. The technology for handling radioactive wastes and methods for immobilizing radioactive wastes in repositories are briefly described. Ways to eliminate radwaste repositories containing medium-level wastes with fissile substances and α-emitters are proposed. The experience gained in such work abroad is examined and the problems which must be solved to rehabilitate the objects at the Works are noted.The main result of the examination of the Kirovo-Chepetsk Chemical Works performed by specialists from the Center for Federal Property Management, the Russian Science Center Kurchatov Institute, and the Moscow Scientific and Industrial Association Radon in 2007-2008 was a concept for rehabilitating radioactively contaminated objects and grounds of the Kirovo-Chepetsk Chemical Works while assuring the radiological safety of the people living in Kirovskaya Oblast [1]. Possible technologies for handling the radwastes formed during the rehabilitation work must be identified and examined in order to develop a project for decommissioning and rehabilitating a radiologically dangerous object. A special feature of the radiation conditions at the Works is the wide assortment of contaminating radionuclides, including fissile materials, actinides, and fission products. It is precisely the technologies for eliminating, isolating, and immobilizing wastes containing the radionuclides mentioned that must be regarded as the primary technologies which will be used for rehabilitation and decommissioning nuclear and radioliogically dangerous objects of the Works.The objective of using the technologies considered must be to eliminate wastes during the liquidation of radiologically dangerous objects, reduce their volume to be disposed of, and stop the radionuclides from entering the environment. These are the standpoints from which the technology must be viewed at the objects to be rehabilitated.Technologies for Equipment Decontamination and Disassembly. A radiation survey of the objects at the Works showed that the primary problem of rehabilitation is the removal of wastes from the process systems and the disassembly of the equipment in building No. 93, whose state at this time is close to being an emergency. Visual inspection of the ventilation system showed that process deposits ranging in thickness from 1 to 5 cm and more are present at the bottom of the air ducts (see Fig. 1). Estimates show that up to 3.6 tons of medium-level wastes containing isotopes of fissile elements are concentrated in the ventilation systems of this building. It is proposed that the ventilation systems and equipment be disassembled by means of cold cutting methods and robot technology [2][3][4][5]. The wastes are to be removed by mechanical methods using at the final stage hydroabrasive decontamination or high-pressure water jets.