Summarizing materials above we can make the following conclusions.
On Optimisation of exposures during operations (project manager: A V Simakov)
1. Analysis of the system for the radiation situation monitoring and of the system for individual dose monitoring which operate at SevRAO facility No.1 has been performed.
It was shown that now, at the stage of SNF and RW storage:
• existing radiation monitoring system promotes obtaining of comprehensive information about radiation situation conditions in the main industrial areas; this system complies with OSPORB-99 and NRB-99 requirements;
• existing PDM system promotes obtaining of comprehensive information about occupational doses; this system also complies with regulative requirements.
2. When going on to full-scale construction works and commissioning of the Combines for SNF and RW management, amount of radiation hazardous operations will increase considerably. In order to implement an optimization principle, under these conditions, the radiation monitoring system is reasonable to be enhanced, focusing on increasing monitoring extent and full-scale introduction of ASKRO system – depending upon established engineering procedure of work implementation.
3. When improving PDM system, special attention shall be paid to:
• enhancement of personal dosimetry method with respect to external beta exposure to the skin;
• introduction of emergency neutron dosimetry;
• turn to application of thermo-luminescent dosimeters to assess external gamma doses;
• introduction of radionuclide intake assessment method in terms of the radionuclide activity concentrations in air of working area.
4. In order to manage and to perform actions aimed at the optimization principle implementation, the requirements of the Guidelines MU 2.6.5.0.-08 developed within the present project and aimed at ALARA strategy introduction into SevRAO Facility No.1 practice must be observed.
On VLLW management (project manager: V G Barchukov)
1. The Russian sanitary legislation envisages availability of the waste category, which complies with international practice and corresponds to the very low level waste (VLLW) category.
2. To put terminology of Russian regulative basis into compliance with the international one, industrial waste containing man-made radionuclides with specific activity levels lower than LLW, but higher the level of exemption from radiation control, are reasonable to separate into the category of "very low level waste" (VLLW).
3. OSPORB-99 Para.3.11 defines the main criteria specifying the bound values for this waste category (specific activity levels). In respect to SevRAO conditions the level of clearance from the radiation control is 0.3 kBq/kg, but that VLLW specific activity level must be less than 12 kBq/kg on average, while with the purpose of the containment barrier justification, average values of specific activity may reach 30 kBq/kg, and in some packages – up to 100 kBq/kg.
5. VLLW landfill safety during the post-operational period is being defined by the most acceptable scenario of its use after completion of the relevant investigations and its coordination with the supervision bodies according to the established procedure.
On criteria for monitoring and control of the arine environment (project manager: N K Shandala) 1. A database has been developed on radionuclide contents in the marine environmental media. This
database is stored in the special data manager software Access. The database includes a set of inter-connected tables containing the following information:
• sampling points;
• marine environmental media;
• radionuclides under control;
• specific activities of radionuclides in the marine environmental media;
• methods of sample treatment and measurement procedures;
• organizations performed measurements.
The database includes verified information on radionuclide activities in the marine media from different literature sources. Protocols of sampling and of sample measurements in respect to the marine environmental media have been developed.
2. On the base of dose criteria and remediation regulations for STS sites and facilities, derived levels had been developed of marine and terrestrial environmental contamination in a form of:
• specific activity of radionuclides in soil (residual activity);
• specific activity of radionuclides in bottom sediments;
• activity concentration of radionuclides in seawater.
The derived criteria will permit to control the observance of established hygienic regulations of remediation in terms of results of radiation control and monitoring.
3. Official guidelines have been developed, which regulate sanitary epidemiological and organizational requirements for organization of radiation hygienic control and monitoring of environmental media radioactive contamination within health protection zones and supervised areas of STS (selection of observation points, determination of parameters under control, frequency and extent of control) in the following situations:
• under condition of routine SNF&RW STS operation;
• in the course of STS remediation including SNF&RW removal;
• in case of radiological accident.
The research radiation hygienic monitoring serves as the methodological base of the developed document. This monitoring is being defined as a system of overall dynamic observation, which includes long-term permanent control both of parameters of the radiation hygienic situation and of doses to the public living nearby radiation hazardous STS facility locations.
On criteria for implementation of emergency plan and early response actions (project manager: M N Savkin)
1. Based on the analysis of international (IAEA) and national (Russian) requirements related to assessing and application of operational radiological and medical criteria at the early phase of an emergency some distinguishes have been identified. However, they are not principal a conclusion
can be done that the both systems of operational criteria at the early phase of an emergency recommended by IAEA and used in Russia as a whole are consistent.
2. The ambient dose equivalent has been selected as an operational radiological criterion to support decision-making accounting for specific of potential radiological and medical threats at the SevRAO facilities. This selection is met to the three requirements: prompt and easily measurable;
representative; and important with respect to dose assessment. Numerical values for operational criteria to announce two levels of radiological conditions, to provide emergency zoning, prompt assessment of justification of introducing intervention for radiation protection of the public have been determined. The values corresponding to low intervention level given in section 6 in NRB-99 were used as the basis to develop operational criteria for the public.
3. The data from the service of radiation safety of enterprise and results of medical and hygienic inspection of victims in medical institutions of FMBA (Medical Sanitary Unit # 120, Centre Sanitary Supervision-120, State Research Centre –Institute of Biophysics, Clinical hospital # 6) have been used as the basis for development of medical criteria. Obtained data are systematized for each stage of medical aid, also, on the urgency of conducting the procedures. The most typical erroneous actions of medical personnel with some forecasted situations and states of victims in the different stages of medical aid are described. The developed criteria are practical management for decision making on medical interference. Usage of medical and sanitary criteria will make it possible to successfully solve the tasks of emergency medical response and to preparedness planning the actions of the service of the medical protection of SevRAO facilities and medical institutions of FMBA.