The first step is to define the performance limiting factors in the application. For this application, most of the adsorber is used for MTBE adsorption in the ppb concentration range. Adsorption of BTEX, TBA, or humic acids or other total organic carbon (TOC) components are removed by the front end of the column. In theory, any multi-component adsorption application can be split up into multiple objectives and more than one carbon selected. For example, and optimal MTBE carbon on the effluent end of the column and a different optimal TOO removal carbon on the influent. In practice, few customers optimize their carbon selection to a level that justifies application of multiple carbons. If only one optimized carbon is applied, then it should be optimized for the species utilizing the greatest amount of carbon.