Pursuant to section 112 of the Clean Air Act as amended in 1990 (the Act), this action promulgates final standards that limit the discharge of chromium compound air emissions from existing and new hard chromium electroplating, decorative chromium electroplating, and chromium anodizing tanks at major and area sources. Chromium compounds are among the 189 hazardous air pollutants (HAP) listed for regulation under section 112 of the Act. Hard and decorative chromium electroplating and chromium anodizing tanks have been identified by the EPA as significant emitters of chromium compounds to the atmosphere. The purpose of the final rule is to reduce chromium compound air emissions from the source categories identified above. All affected sources must limit emissions to the level of the maximum achievable control technology (MACT). The EPA is also finalizing Methods 306, 306A, and 306B with these standards.