Determination of effective vertical migration velocity and residence times of 137Cs in sediments of Mumbai Harbor Bay using compartment models

The vertical concentration profile of 137Cs in core sediment of Mumbai Harbour Bay has been studied by the compartment models. Based on the measured concentrations of 137Cs in the sediment layers, the transport parameters as residence half life and effective migration velocity were determined. The residence half lives were observed to be 5 years and 13.6 years in cores L-3 and L-5 respectively. The corresponding effective migration velocity was obtained to be 7.2 cm/y and 3.23 cm/y over the core length of 36 cm and 44 cm respectively. The migration velocities obtained were well within reported values in literatures. (author)