RADIOACTIVE CONTAMINATION AROUND A BOILING WATER-REACTOR MAIN TURBINESYSTEM AND PROCEDURES FOR MINIMIZING THE CONTAMINATED AREA

From analyses of the isotopic contribution of radioactive contaminatio n on major components around the main boiling water reactor turbine sy stem and the isotopic distribution along the system, the following con clusions are drawn: 1. Contamination, especially on components that ar e installed downstream of the low-pressure turbine, is caused by the d rain of surplus reactor wafer into the main condenser. 2. Contaminatio n if from radioactive fission products and radioactive corrosion produ cts that are carried with the main steam flow. To reduce radioactive c ontamination, it is most important to drain the hot water directly int o the radwaste system, To reduce contamination from carryover radioact ivity, it is essential to suppress the radioactivity in the reactor wa ter Preventing fuel defects and suppressing the radioactivity of crud in the reactor wafer can decrease contamination of the main turbine sy stem and minimize the contaminated area, which lessens the possibility of internal exposure.