Silenium Removal General Mineral Analysis And Design Data Bulletin

Dissolved selenium (Se) occurs naturally in water supplies as a result of sulfides or native sulfur deposits, not artificial contamination. Well waters generally have higher selenium concentrations than surface waters due to the fact that they have greater exposure to selenium bearing minerals. The United States Environmental Protection Act (USEPA) has established regional Maximum Contaminant Levels (MCL) for selenium that are based on the probable daily ingestion of water. The optimum selenium level established by the United States Public Health Service (USPHS) is one­ half of the MCL. The EPA MCL for selenium is 0.05 mg /L (50 pg / L).