The EPA will publish a plan and schedule to identify four industry sectors for possible new or updated wastewater effluent controls. Under the agency's 2004 Effluent Guidelines Plan, two industrial sectors identified for potential revisions to existing effluent guidelines are vinyl chloride manufacturing and chlor-alkali manufacturing.

Two unregulated industrial categories also called out are airport de-icing operations and drinking water supply and treatment. To date, the EPA has issued effluent guidelines for 56 industries. The agency estimates that these regulations prevent the discharge of more than 690 billion pounds of pollutants each year.

The Clean Water Act requires the agency to annually review and, if appropriate, revise existing effluent guidelines. From these reviews, the EPA publishes an effluent guidelines plan every two years. Visit www.epa.gov/guide/final-fs2004-2005plan.htm.