On March 29, 2013, the Environmental Protection Agency (“EPA”) issued updates to its emissions limits for new power plants under the mercury and air toxic standards (“MATS”).  The less stringent limits are a result of new information and analysis the EPA received during the reconsideration period of MATS.  The EPA stated that the revisions should not alter the control technologies that owners and operators must install to comply with MATS.

Notably, the EPA revised the emission limits on (1) hydrogen chloride; (2) filterable particulate matter (“PM”); (3) sulfur dioxide; (4) lead; and (5) selenium emitted from all new coal-fired plants.  Additionally, the EPA revised the limits for mercury emission limits for units in the 8,300 Btu/lb subcategory; filterable PM and sulfur dioxide limits for new solid oil-derived fuel-fired plants; filterable PM emission limits for continental liquid oil-fired plants; and most emission limits for new integrated gasification combined cycle units.  New plants must comply with these standards when the revised final rule is published in the Federal Register, or at startup, whichever date is later.

Additionally, the EPA announced that it was removing the option of using quarterly stack testing as an option for new plants’ compliance with filterable PM limits, and requiring inspection and retesting within 45 days after a new plant exceeds the emissions limits when using the PM continuous parameter monitoring systems as a compliance option.  Finally, the EPA stated it was finalizing a presumption of a violation if a new plant requires four or more emission tests within a 12-month period.

A copy of the Final Rule is available here.