Desorption is one of the most critical processes affecting the effectiveness of soil and groundwater remediation. However, none of the currently adopted desorption models can accurately quantify desorption of low-hydrophobicity organic chemicals, which often misleads remediation design and decision-making. A recently developed dual-equilibrium desorption (DED) model that is based on readily available physical and chemical parameters was found to be much more accurate in quantifying sorption and desorption. A screening-level transport model, DED-Transport, was then developed to simulate the DED effect on behaviors of organic contaminant plumes during remediation. DED-Transport requires only simple parameters but is applicable to many remediation scenarios. DED-Transport can be used as a decision-support tool in site remediation to more precisely predict the time required for cleanup.