This study measures, with use of a simulation model, expected increases in congestion cost as additional export grain moves through a representative Gulf port elevator and the associated intermodal transfer system and examines the feasibility of congestion-reducing investment in the port elevator. Analyses indicates congestion cost increase substantially as port elevator volume exceeds 125 million bushels. Further analysis indicates congestion-reducing investment by the port elevator to be economically feasible, i.e. through modification of existing plant the efficiency of the port elevator can be maintained as export volume increases.