Integrated Residuals Management in Industry
We now turn to a discussion of specific case studies of industries. Because each of the industries studied represents a degree of complexity that cannot be completely reflected here, we present only a sampling of approaches and results, emphasizing the utility of such studies and what has been, and can be, learned from them. Because the studies considered here are the result of a more or less continuous evolution in concepts and methodology in the RFF Quality of the Environment program over a period of some ten years, it will be worthwhile to recount a little of this history.
The first efforts at detailed industry studies focused on the demand for water as an input to production processes. They reflected, first, the wide- spread concern at the time with the possible scarcity of resource inputs to support continued economic growth, and second, the fact that previous efforts with respect to estimating future industrial water needs had been done on a very rudimentary and naive basis. Traditionally, industrial water needs had been estimated on the basis of historical information on gallons per employee, gallons per unit of raw product processed, gallons per unit of final product output, and even gallons per acre of type of industrial activity, for example, "light manufacturing." The basic data used were aggregate data, that is, across a given industry and based on nationwide mail questionnaire surveys, such as those of the Bureau of the Census. In general, none of the estimates by public agencies and private firms considered explicitly the effects of: (1) changes in production technology, raw materials, product mix, and product output specifications; (2) the price of water at both intake and outlet, as price affected indus-