Alabama Power Co. v. Environmental Protection Agency

Congress amended the Clean Air Act in an effort to curb the effects of acid rain. The amendments placed limits on the amount of nitrogen oxide (NOx) particles that coal power plants could emit. Congress delegated rulemaking provision to the Environmental Protection Agency (EPA) (defendant). Under the statutory scheme, the EPA generally could not set limits that exceeded the NOx particle limits that Congress set in the statute. However, a coal power plant could exceed the statutory limit if it received permission from the EPA. The EPA had to authorize such permission if a utility demonstrated that it could not meet the limit using low-NOx burner technology, among other requirements. Moreover, the EPA could not require a power company to install technology beyond low-NOx burners. The EPA engaged in rulemaking, which involved defining the term “low-NOx burner technology.” The EPA broadly defined that term to include (1) the use of burners designed to reduce NOx emissions and (2) a control method known as overfire air. Thus, under the EPA’s definition, to avoid the statutory emission limits, a power plant would be required to use both burners and overfire air before it could receive an exemption from the statutory emission limits. The Alabama Power Company and other coal utilities (plaintiffs) petitioned to set aside the rule on the ground that the EPA had exceeded its statutory authority by defining “low-NOx burner technology” more broadly than Congress intended.