67 Corrosion-induced whole effluent toxicity from a cooling to wer: a toicity reduction evaluation case study

摘要

As the result of Whole Efflucent Toxicity (WET) test failures with Daphnia pulex, the U.S. Environmental Protection Agency (EPA) required an industrial facility discharging approximately 5 million gallons per day (MGD) of recirculating cooling water obtained from a large freshwater river to conduct a toxicity Reducton Evaluation (TRE) program. Under the terms of the Nationa Pollutant Discharge Elmination System (NPDES) permit, the facility was required to conduct 48-hour acute toxicity tests with D. pulex and Pimephales prolmelas (fathead minnow) Although effluent toxicity to D. pulex was consistently observed, no toxicity was induced to the fatheeadminnow during the TRE program. The situation was futhre complicated by the fact that the recirculating cooling water was discharged back into the same river. A block flow diagram of the cooling wwater system is given in Figure 1. The objectives opf the TRE program were to investigate the cause of toxicity, locate potential sources of the suspected toxicant(s), and identify practicable toxicity reduction methodologies to be used. The TRE progam approach and results from the WET problem.