Clean Water Act Regulations affecting Electric Utilities Julie Hewitt US EPA, Office of Water October 22, 2010 BPC/NARUC/NESCAUM Workshop

Two CWA Rules in Development Steam Electric Effluent Limitations Guideline (ELG) Revision of 1982 rule §316(b) Cooling Water Intake Structures (CWIS) Regulation for Existing Facilities Rule responding to court decisions

Steam Electric ELG Steam electric category is a subset of all electric generating activities Includes fossil (coal, oil, gas) and nuclear-fueled power plants, but not fuels such as biomass, tires, etc. Detailed review of steam electric ELG completed in 2009 Focus on coal-fired plants: 500 plants (700 are nuclear, oil and gas) Most toxic pollutants are released by flue gas desulfurization (FGD) wastewater & ash ponds

Coal combustion wastewater Current ELGs regulate suspended solids and oil & grease from ash ponds & FGD discharges Unregulated pollutants present in ash ponds, FGD wastewater, & landfill leachate Metals Mercury, selenium & arsenic are of most concern Bioaccumulative Nutrients, especially nitrogen (nitrates, ammonia) Total dissolved solids, chlorides Simplified Diagram of Selected Wastes at a Coal-fired Power Plant

Schedule for SE ELG Survey to collect technical and financial information for analysis is underway Agency intends to issue proposed regulation in mid-2012 Rule will have effective date 60 days after publication Dischargers must have NPDES permit NPDES permits are for 5 years Compliance likely will have to occur by next permit renewal cycle

§316(b) CWIS Regulation Original rule issued in 2004 Portions remanded to EPA by 2nd Circuit Portions upheld by Supreme Court in Entergy decision 1,260 existing facilities collectively withdraw 226 billion gallons of water per day Main environmental impacts Impingement and entrainment Thermal discharges may also be significant for some waters

Cooling Water Basics Fixed Bar Racks Traveling Screens Larger fish unable to swim away are impinged against the screen and usually die. Smaller organisms that pass through the screens are entrained in the cooling system and also die. Once through cooling uses water only once as it passes through a condenser to absorb heat and is then discharged. Closed-cycle cooling reuses water by recycling it through recirculating systems or towers. 7

Schedule for §316(b) Rule Also effected through NPDES permits and 5 year cycle Agency’s intent is to issue final rule by July 2012