Provides guidance on the general approach & procedures for conducting Toxicity Reduction Evaluation (TRE) at municipal wastewater treatment plants. TREs are important tools to use to identify & reduce or eliminate toxicity in a wastewater discharge. TREs may be required by the discharger's permit or through state or Fed. enforce. actions. Dischargers can use the guidance to evaluate the nature & sources of effluent toxicity (ET) before a TRE becomes a regulatory require. Whether the TRE is voluntary or mandated, this guidance, which describes the approaches that have been successfully used in municipal TREs, can help to prepare & execute a plan to address ET. Illus. Also includes a 9-page EPA report, Assessing Contaminant Sensitivity of Endangered & Threatened Species: Effluent Toxicity TestsÓ (Sept. 1999).

In the reauthorization of the Clean Water Act in 1987, the U.S. EPA specifically addressed toxics management. In addition to the requirement to eliminate discharge of toxics, there can be a requirement to conduct a toxicity reduction evaluation (TRE). The scope of toxicity reduction varies from the very simple and inexpensive to the highly complex and costly. This book, volume three of the Water Quality Management Library, provides a complete overview of toxicity reduction evaluation. The book presents the testing and removal of toxicants, toxicity testing procedures, sampling techniques, baseline collection data, and source identification. Plus, the book presents toxicity reduction methodologies including unit processes necessary for organic toxicant control using biological and physical chemical methodologies as well as selected unit processes necessary for inorganic toxicant control.