Treatment of industrial wastewater with granular activated carbon began in the United States, the UK and Germany during the early 1960s. The development of a high-surface-area carbon that could be reactivated made adsorption economically practical for removing dissolved organic contaminants from wastewater. Another improvement has been the increased hardness of the activated carbon granules, which makes reactivation and repeated reuse feasible. Attrition and carbon losses during reactivation are kept to a minimum with carbons having high hardness.