A rapid-response Lagrangian model for simulating the transport of a chemical pollutant in the Arabian/Persian Guls is described. The model is well suited to provide a fast response after an emergency due to an accident or a deliberate spill. Baroclinic circulation was obtained from HYCOM ocean model and tides were calculated using a barotropic model. The interactions of pollutants with sediments (uptake/release processes) were described using a dynamic approach based on kinetic transfer coefficients and a stochastic numerical method. Some examples of model applications are shown.