Carbon's great efficiency in organic removal has promoted its use for upgrading conventional plant performance. Successful use of carbon in tertiary treatment has led to proposals that it be used for secondary treatment as well, i.e., as a replacement for biological treatment. The manual examines major design parameters and unit operations (including pretreatment) which are important in carbon adsorption systems. Existing carbon plant designs are evaluated. Costs are evaluated for the various unit operations. Various plant configurations are discussed. Carbon regeneration (a prerequisite for economic feasibility) is discussed and the necessary equipment is described. Other aspects discussed include: air pollution control devices for the regeneration furnace, personnel requirements, isotherm and pilot testing, carbon dewatering, biodegradation of organics in carbon columns. (Author)