Operative automated monitoring of the fission product radioactivity in the water coolant of a nuclear reactor

concerning the radioactivity of the corrosion products in the reactor water (Table 3). With transition from the uncorrected to the oxygenous regime, the radioactivity of the reactor water, due to 59Fe, was reduced considerably. As, in the operating periods being compared, the reactor power was unchanged, the results obtained confirm the reduction of the content of steel corrosion products in the feed water. A similar reduction of the 56Mn concentration also is due to the reduction of the removal of corrosion products from the surface of the carbon steel. The increase of radioactivity of the coolant due to 6~ having started during the uncorrected regime, and also the reduction of 65Zn in the coolant and deposits (see Table 3), is due to the replacement in 1972-1974 of the brass tubular bundles of the turbine condenser by MNZh-5-1 alloy, which also explains the high content of copper in the coolant (see Table 2).