This web service contains the following layers: Mandatory Class 1 Federal Area polygons and Mandatory Class 1 Federal Area labels in the United States. The polygon layer draws at all scales. The labels draw at scales greater than or equal to 1:3 million. Data used to create this web service are available as a separate download at the secondary linkage listed above. Full FGDC metadata are available by clicking the layer name in the web service table of contents and clicking the Full Metadata link in the layer description. This dataset was developed by EPA's Office of Air Quality Planning and Standards (OAQPS) based on features originating from several data sources, including USEPA, USFS, USFWS, NPS and BIA.