This rule establishes air quality designations for most areas in the United States for the 2008 lead (Pb) National Ambient Air Quality Standards (NAAQS). In a previous action established on November 16, 2010, the EPA designated as "nonattainment" 16 areas as violating the 2008 Pb NAAQS based on data from the pre-2010 monitoring network. For all other areas, the EPA deferred action so that data from newly deployed monitors could be considered in making appropriate designation decisions. In this action, the EPA is designating all remaining areas of the United States, including Indian country. The Clean Air Act (CAA) requires areas designated nonattainment by this rule to undertake certain planning and pollution control activities to attain the standards as quickly as reasonably possible.