On May 8, 2007, the EPA published a supplemental notice of proposed rulemaking effecting permitting requirements for existing electric generating units (EGU) which plan a modification. (72 FR 26201). The EPA proposes to revise the preconstruction permitting requirements for EGU’s under the New Source Review (NSR) Program. Currently, a physical change or change in the method of operation that results in an annual emissions increase would trigger NSR permitting, which would require an EGU to install modern pollution controls.

In 2005, the EPA proposed replacing the annual emissions test with an hourly emissions test. Under the newly proposed rule, the EPA would consider the impact on both hourly emissions and annual emissions. If the planned change does not result in an increase in the plant’s hourly emissions, then no NSR permit will be required. If hourly emissions will increase, then annual emissions are evaluated. Only if both the hourly emissions and annual emissions are expected to increase will an NSR permit and associated pollution control devices be required.

The EPA has determined that the new rule would eliminate “administrative and other barriers that the power sector faces regarding safety, reliability, and efficiency improvements.” Environmental groups claim the rule will result in devastating impacts on local and regional air quality. Public comments are due by July 9, 2007.

Click to link to the EPA website for more information.