Tritium levels in the environment of KAPS - an indicator of quality performance

Tritium is produced in the Pressurized Heavy Water Reactor by the activation of Heavy water used as moderator and coolant. Due to its large abundance in the reactor and its presence in both liquid and gaseous effluents, Tritium concentration in environmental matrices is an indicator of radioactivity releases from PHWR type reactors. Kakrapar Atomic Power Station (KAPS) is a PHWR type power station located at Kakrapar Village in the Surat district. The station is operating since 1993 and a comprehensive environmental survey program was carried out at this site by Health Physics Division, BARC for radioactivity levels in the environment. The survey carried out at KAPS environment for the past ten years (1994-2003) reveals that there is no increase in radiation levels and tritium is the only radionuclide detected in environmental matrices. The yearly average committed effective dose due to Tritium in the environment works out to be about 2.2 μSv, which is a conservative figure and is of very low significance. The life time stochastic risk to the total population (all age group) attributable to 2 μSv effective dose works out to be 1x10-7 which is also a conservative estimate and can be considered to be very safe. The very low committed dose observed in KAPS environment, indicate the quality performance of the station. (author)