Document: NUREG-0800
Document ID: ac43f632-9db1-4857-9f56-bfba45965456
Document Type: srp
Title: * These are modifications to a plant’s design, operations, or other activities that require NRC approval. These modifica
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0232/ML023250195.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19
CFR Part: 
CFR Title: 

Content:
spread basis and (2) the reviewer has knowledge that the risk impact is not reflected by the licensing basis analysis and has reason to believe that the risk increase would warrant denial or attaching conditions to the staff’s approval if the request were evaluated as a risk-informed application. If one criterion is met, the second would generally be met as well. However, in view of the judgment involved in these determinations, cases in which one of the criteria is not clearly met should still be elevated for management consideration as discussed below. SRP 19-D3 “Special circumstances” may include but not be limited to license amendment requests that, if approved, could —  Substantially increase the likelihood or consequences of accidents that are risk significant but are beyond the design and licensing basis of the plant, for example, proposed changes to steam generator (SG) allowable leak rates that meet 10 CFR Part 100 limits based on the design basis source term but result in a large early release given a severe accident source term; or use of new materials for SG repairs that provide acceptable performance under normal and design basis accident conditions but a reduced capability to maintain SG tube integrity in high- temperature, severe accident scenarios.  Degrade multiple levels of defense, or cornerstones in the reactor oversight process, through plant operations or situations not explicitly considered in the development of the regulations, for example, advanced applications of digital instrumentation and controls in which the licensee does not address or comply with regulatory guidance concerning evaluation of defense in depth and diversity in digital instrumentation and control systems.  Significantly reduce the availability or reliability of structures, systems, or components that are risk significant but are not required by regulations, for example, amendment requests that as an unintended consequence compromise the effectiveness of the