It appears inevitable, absent legislative intervention, that regulation under the Clean Air Act (CAA) will move beyond mobile sources to the industrial and power facilities that emit most U.S. greenhouse gas (GHG) emissions. This report analyze the mechanisms available to the EPA for regulating such
sources, and identify one, New Source Performance Standards (NSPS) as the most predictable, likely, and practical, i.e. knowable, pathway. Based on the legal structure of the NSPS and the EPA