The U.S. Environmental Protection Agency (EPA) has published notice that it is taking further public comment regarding the startup and shutdown work practice standards under its Mercury and Air Toxics Standards (MATS, a.k.a., the EGU MACT). The MATS, which includes standards limiting mercury, acid gases, and other pollutants from electric utilities, was finalized by EPA in December 2011. EPA subsequently took several aspects of the rule under reconsideration, such as issues related to work practice standards applicable to startup and shutdown periods. In March 2013, EPA finalized its reconsideration of the rule except for subject startup and shutdown issues, which EPA stated it would address at a future date. EPA is now reopening the public comment period on these startup and shutdown issues, and is requesting comment regarding:
1) The definition of startup and shutdown (e.g., when do these periods begin and end);
2) The definition of “clean fuels,” which must be used under the MAT’s startup and shutdown work practice standards;
3) The use of default diluent gas cap values during periods of startup and shutdown;
4) The calculation of startup and shutdown emissions when multiple affected units share a common stack; and
5) The use of a default electrical production rate value to calculate output-based emission limits during startup and shutdown hours where the electrical load is zero.
Comments are due by August 26, 2013. Further general information regarding MATS is available here.
For more information, please contact Joseph Brown.