Emission Sources

Periodic Monitoring Update

In September 1998, EPA issued guidance to clarify the periodic monitoring rule requirements. 

On April 14, 2000 the U.S. Court of Appeals for the District of Columbia Circuit decided to set aside EPA's guidance. Specifically, this decision sets aside EPA's guidance in its entirety, and specifically says that states cannot use the guidance or EPA's existing operating permit regulations to require more frequent monitoring of emissions than provided for in existing state or federal standards, unless that standard requires no periodic testing, specifies no frequency, or requires only a one-time test.

Environmental Protection Examples