Many wastewaters contain significant levels of organic contaminants which are toxic or otherwise undesirable because they create odor, bad taste, unsightly color, foaming, etc. These substances are often resistant to degrada tion by biological methods, and are not removed effectively by conventional physicochemical treatment methods, such as coagulation/flocculation, sedi- mentation, filtration, and ozonation. Because activated carbon has a strong affinity for binding organic sub- stances, even at low concentrations, it has become the premier method for treating organic-laden wastewaters. It also is widely used for purifying drinking water from sources containing relatively small but offensive levels of organic contaminants.