Plant-Specific Applicability of Transition Break Size Specified in 10 CFR 50.46a

The U.S. Nuclear Regulatory Commission (NRC) is announcing the discontinuation of further regulatory action on Draft Regulatory Guide (DG) DG-1216, "Plant-Specific Applicability of Transition Break Size Specified in 10 CFR 50.46a," and its withdrawal. Draft Regulatory Guide DG-1216 was a proposed new regulatory guide written to provide implementing guidance for a proposed rule "Risk-Informed Changes to Loss-of-Coolant Accident Technical Requirements," (Emergency core cooling system (ECCS) rulemaking)) that provided a voluntary, alternate approach for evaluating the performance of an ECCS. The NRC is discontinuing further regulatory action on the DG and not publishing the DG in final form because the NRC has discontinued the underlying rulemaking.