On-line environmental radiological data acquisition system for nuclear facilities and sites

After the Cosmos, Chernobyl and Goiania accidents, upgraded state of the art systems and methodology for the surveillance of environmental radioactivity have been recognized world over. These include both site-specific as well as nation-wide systems and programmes. The modules of such systems are basically on-line networks with fixed and mobile monitoring units. The topology of the Bhabha Atomic Research Centre, Trombay site, where all major components of nuclear fuel cycle activities are located is very complex in nature. The assessment of the radiological impact, if any, due to atmospheric releases from these facilities within Bhabha Atomic Research Centre site is being carried out by using a Modem based Early Warning System (MEWS). The system is aimed at providing data during normal operation of the plants and for providing early warning to decision makers in case of an emergency. It is done by acquiring both on-line and off-line data on releases from the plants, the environmental radiation dose rate at selected locations and other related parameters. The monitors placed at these strategic locations around the Bhabha Atomic Research Centre site can also help in detecting any attempt of unauthorized trafficking of the radioactive sources. This paper explains different aspects of the system operating at Bhabha Atomic Research Centre. (author)