Effect of water chemistry on the radioactive contamination of WWER power reactor components

Effect of water chemistry on radioactive contamination of reactor components is studied, using as an example the Kola NPP. Indices characterizing the quality of the in-pile environment are analyzed. Data are analyzed on the radioactivity of deposits, including 51Cr, 58Co, 54Mn, 60Co, 59Fe, sup(110m)Ag, 95Zr in the steam generator, circulation pumps, reactor vessel and control and safety system during shutdown of unit 2 at the Kola NPP. Dose rates from the equipment at units 1, 2 and 3 at the Kola NPP after the first fuel run are presented. It is shown that introduction of hydrazine into the primary circuit of the WWER reactor improves the radiation situation due to: preation of a deeply reductive mediumt, decrease in the corrosion rate of structural materials, decrease in pollution coefficient and absence of loose deposits on the surfaces of the circulation line, decrease in time of neutron irradiation of corrosion products in the reactor core, improvement of the fuel assembly surface puAity. The conclusion is drawn that there is a possibility to create nuclear steam supply system with safe levels of radioactive contamination without application of chemical decontamination techniques