The Ohio River Valley Water Sanitation Commission's Toxic Substances Control Program for the Ohio River

Abstract

The Ohio River Valley Water Sanitation Commission (ORSANCO) is an interstate agency created in 1948 to administer a state compact which calls for the abatement of water pollution in the Ohio Valley. Since 1975, ORSANCO has conducted routine monitoring programs to detect the presence of toxic chemicals in the Ohio River and in fish taken from the river. Such information is particularly important as the Ohio River, a major river in the United States, serves as a water supply to over three million people and is used extensively for recreational purposes. The monitoring results have shown several problems: contamination of fish tissue by PCBs and chlordane, concentrations of certain metals which exceed chronic aquatic life criteria in 10 to 25 percent of the samples analyzed, and levels of certain volatile organic compounds which exceeded criteria established to prevent one additional cancer per one million population in almost half the samples analyzed. In 1986, the Commission initiated a Toxic Substances Control Program which was designed to identify sources of the toxics problems and prescribe corrective actions. Because of the multitude of potential sources of toxics along the Ohio, the river was divided into seven segments for intensive study. To date, studies have been initiated on four segments. In addition, special topic studies have been conducted on the river as a whole to address the suitability of the river as a source of drinking water, trends in parameter levels, and the relationship between surface and ground water quality. Findings to date:Point source discharges to the river do not cause widespread toxics problems.Nonpoint sources, including urban runoff and contaminated ground water, are significant sources of toxics to the river.Levels of certain toxics in tributaries are also an important source.Under “normal ” situations (i.e., excluding spills), the Ohio River provides a suitable source water for public supply after appropriate treatment.Levels of many metals and volatile organic compounds have decreased over the past 10 years.