Book excerpt: Prior to the starting of any nuclear power station, it is very important to record the status of the environment with regard to its quality and demographic features of the immediate neighbourhood. In the global scenario, India occupies the prime position as the initiator of this procedure as far back as the sixties. This venture is termed as ‘pre-operational environmental baseline study’. Such surveillance is also mandatory to fulfill regulatory requirements before commissioning of the plant. Pre-operational monitoring helps in assessing the impact of the facility during its operational phase. Hence, a systematic study is essential to establish the baseline data regarding natural and fallout (man-made) radioactivity in various environmental samples before the plant goes into operation. Such surveillance also includes measuring and monitoring conventional parameters in respect of air and water quality in the surrounds of a nuclear facility.