The manufacture of pulp and paper involves the use of water in almost every unit process. Integrated mills (those having both pulp and paper making facilities) have historically been located along a large, readily available supply of fresh water. Unlike many other industries which use a majority of fresh w-ater for cooling purposes, the paper industry uses a substantially larger fraction of water in the manufacturing process itself. Unit processes which require significant water use include wood handling, pulping, pulp screening and cleaning, pulp bleaching, chemical recovery, pulp storage and papermaking, and power generation. Figure 1 provides a schematic of water use in a hypothetical bleached kraft mill.