DETERMINATION OF C-14, H-3 AND GAMMA-EMITTING RADIONUCLIDES IN IRRADIATED ZR-2.5NB PRESSURE TUBES

Information on the activities of C-14 and other long-lived radionuclid es in irradiated pressure tubes from CANDU(2) reactors is required for reactor maintenance and to develop the strategies for longterm waste management of wastes arising from reactor retubing or decommissioning. Radiochemical data on the activity levels of C-14, H-3 and gamma-emit ting radionuclides in seven Zr-2.5Nb pressure tubes from reactor units 3 and 4 of Ontario Hydro's Pickering Nuclear Generating Station are p resented. Details of the analytical method to measure C-14 in the pres sure tubes using an ellipsoidal infrared spot heater are given. The me asured C-14 data are compared with calculated values derived from the operating history and the concentration of nitrogen impurities present in the tube alloy.