A method for reducing one or more additives in a gaseous hydrocarbon stream (40) such as natural gas, comprising the steps of: (a) admixing an initial hydrocarbon feed stream (10) with one or more additives (20) to provide a multiphase hydrocarbon stream (30); (b) passing the multiphase hydrocarbon stream (30) from a first location (A) to a second location (B2); (c) at the second location (B2), passing the multiphase hydrocarbon stream (30) through a separator (22) to provide one or more liquid streams (50) comprising the majority of the one or more additives, and a gaseous hydrocarbon stream (40) comprising the remainder of the one or more additives; and (d) washing the gaseous hydrocarbon stream (40) in a decontamination unit (24) with a washing stream (60), wherein the washing stream (60) comprises distilled water, to provide an additive-enriched stream (70) and an additive-reduced hydrocarbon stream (80).