ENV-98-182 Selenium Removal From Petroleum Refinery Wastewater

Description:

Selenium in petroleum refinery wastewater is a permitting issue in Texas and California and will likely become a national issue in the future. The challenge for the petroleum industry is to identify a mechanism by which they can meet the selenium discharge criteria. The United States Environmental Protection Agency (USEPA) is reviewing the water quality criteria for selenium based on scientific data that have been available since 1987 that indicate that selenium may be toxic at concentrations less than the current chronic water quality criteria. The USEPA is considering the toxicity of selenium in its various oxidative states in surface water as well as the bioaccumulative nature of selenium. The USEPA is developing a food web model and a guidance document for developing site-specific aquatic life criteria for selenium. Ultimately, the USEPA must decide if the current chronic freshwater criterion of 5 micrograms per liter @g/L) is protective of aquatic life or if the criterion should be lowered, as the United States Fish and Wildlife Service (FWS) recommends.