The U.S. Nuclear Regulatory Commission (NRC) is issuing a new regulatory guide (RG) 4.22, "Decommissioning Planning During Operations." The guide describes a method that the NRC staff considers acceptable for use by holders of licenses in complying with the NRC's Decommissioning Planning Rule (DPR) (76 FR 35512; June 17, 2011). The DPR went into effect on December 17, 2012, and is intended to minimize the likelihood of new "legacy sites," which are NRC-licensed facilities with insufficient resources to complete decommissioning activities and termination of a license at the end of operations.