The Environmental Protection Agency (EPA) is amending regulations under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended, to remove caprolactam (CAS No. 105-60-2) from the list of CERCLA hazardous substances. CERCLA section 101(14) defines the term hazardous substance by referring to those substances listed under several other environmental statutes, including section 112(b) of the Clean Air Act (CAA), as well as substances designated by EPA as hazardous under CERCLA section 102(a). Today's action follows the removal of caprolactam from the list of hazardous air pollutants under section 112(b)(1) of the Clean Air Act Amendments of 1990. The effect of today's action is that caprolactam is no longer a CERCLA hazardous substance. Persons in charge of vessels or facilities from which caprolactam is released are no longer required to immediately notify the National Response Center of the release under CERCLA section 103, and are not subject to the liability provisions under CERCLA section 107. Unless EPA receives adverse written comments during the review and comment period provided in this direct final rule, the decision to remove caprolactam from the list of CERCLA hazardous substances will take effect without further notice as provided in the Dates section of this Federal Register. If EPA receives adverse comment, EPA will withdraw this rule before its effective date by publishing a document in the Federal Register informing the public that the rule will not take effect.