Toxicity of Proposed Water Quality Criteria-Based Mixtures of 11 Inorganics to 'Ceriodaphnia dubia' and Fathead Minnow;Final rept

摘要

The topography of the Northern Black Hills in South Dakota includes a variety of spring-fed cold water streams, which support several species of salmon and suckers along with diverse populations of aquatic invertebrates and aquatic plants. Four watersheds in the Northern Black Hills of South Dakota are currently impacted by acid mine drainage (AMD) produced by five large-scale active gold mines. Acid mine drainage from these mines is discharged into cold water streams after treatment. commonly found in AMD from gold mining include arsenic, cadmium, chromium, copper, cyanide, lead, mercury, nickel, selenium, silver, and zinc. The State of South Dakota, in cooperation with the mining companies, has proposed site-specific water quality criteria for these 11 inorganics in streams receiving AMD. For nine of the eleven inorganics, the proposed site-specific criterion concentrations exceed current national water quality criteria derived by the U.S. Environmental Protection Agency.