Working Paper

A Retrospective Study of EPA’s Rules Setting Best Available Technology Limits for Toxic Discharges to Water under the Clean Water Act

Oct 8, 2015 | Arthur G. Fraas, Alexander Egorenkov


Beginning with the 1972 Clean Water Act, technology-based standards have been a major part of the effort to clean up the nation’s waters. Most accounts of the experience with these standards present a mixed picture. What have they accomplished?

Key Findings

  • Estimates suggest that mills covered by the water limits in the US Environmental Protection Agency’s (EPA’s) Pulp and Paper Cluster Rule achieved little or no additional reductions in toxic discharges compared to other mills in the industry.
  • These results appear to be inconsistent with ex ante estimates that the regulations would achieve substantial reductions in toxic discharges to water.
  • These results are a complement to EPA’s finding in its recent retrospective cost study that the agency overestimated the capital cost of the Cluster Rule by 30 to 100 percent.


Under the Clean Water Act, the US Environmental Protection Agency (EPA) is required to establish standards limiting water toxics discharges from industrial plants. This paper examines the effect of EPA’s 1998 Pulp and Paper Cluster Rule on the discharge of toxics to the waters of the United States. Our estimates suggest that mills covered by the water limits in the rule achieved little or no additional reduction in water toxics discharges in response to publication of the final rule as compared to mills not subject to the water discharge limits of the rule. This paper also offers some recommendations for improving both ex ante and future retrospective analyses.