The EPA is amending the list of hazardous air pollutants in Clean Air Act Section 112(b)(1) by removing the compound caprolactam (CAS No. 105-60-2). This rulemaking was initiated in response to a petition to delete the substance caprolactam which was filed by AlliedSignal, Inc., BASF Corporation, and DSM Chemicals North America under section 112(b)(3) of the Act. Based on the available information concerning the potential hazards of and projected exposures to caprolactam, EPA has made a determination pursuant to Clean Air Act Section 112(b)(3)(C) that there are adequate data on the health and environmental effects of caprolactam to determine that emissions, ambient concentrations, bioaccumulation, or deposition of the compound may not be reasonably anticipated to cause adverse human health or environmental effects. Although EPA acknowledges that there are scientific uncertainties in its analysis of the potential effects of ambient caprolactam exposures, EPA does not regard any of these uncertainties to be sufficiently material to preclude this determination.