EPA PRESS RELEASE - May 25, 2012

Springfield—The Illinois Environmental Protection Agency (IEPA) has granted the Exelon Generation’s Quad Cities Station a provisional variance from the National Pollutant Discharge Elimination System (NPDES) water discharge permitted temperature limits, due to recent unseasonably warm weather conditions.

Quad Cities Station is a nuclear-fueled steam electric generating facility located on the Mississippi River near Cordova. Circulating water used to cool and condense steam from the generating process is ultimately discharged into the river. It does not come into contact with any radioactive components and does not have any impact on radiation risk.

Exelon’s NPDES permit places limits the temperature of the effluent versus the temperature of the river water during a given season, and gives Quad Cities an allowance of excursion hours it can use if its discharge exceeds the temperature. Due to the unusually warm weather conditions, Quad Cities expects to exceed the allowable temperature limit for May on May 26, and requests the variance in anticipation of continuing warm weather.

During the variance period, Quad Cities Station must continuously monitor both discharge and receiving water temperatures and must visually inspect all discharge areas at least three times each day to assess the impact on aquatic life. It must also notify the Illinois EPA and the Illinois Department of Natural Resources if aquatic life is shown to be affected. If the increased discharge temperature results in adverse environmental impact, appropriate reparations must be conducted.

Exelon Generation’s Quad Cities Station must continue to meet all other effluent conditions in its NPDES permit along with additional conditions contained in the provisional variance but not expressly listed above.

The Illinois EPA has determined that any environmental impact from the variance would be closely monitored, and the Agency will be notified immediately of any adverse impacts; no reasonable alternative appears to be available; no public water supplies will be affected; no federal regulations would prohibit granting the request; and the facility would face an arbitrary and unreasonable hardship if the IEPA did not grant the requested variance.

The provisional variance will run through May 29, 2012. All other NPDES permit requirements will remain in effect.