Risk-Informing 10 CFR 50.59 and Allowing Flexibility for Changes to Methods

There are two proposed changes to 10 CFR 50.59, “Changes, tests, and experiments.” The first proposed change to the regulation would allow the use of quantitative risk results to demonstrate a change to the facility does not result in a “more than minimal increase” as the phrase is used in 10 CFR 50.59(c)(2)(i) and (ii). The second proposed change would allow licensees to make changes to methods that would previously have required NRC review under 10 CFR 50.59(c)(2)(viii) or 53.1550(a)(2)(iv), provided the licensee adopts an acceptable verification, validation, and uncertainty quantification (VVUQ) program in accordance with a proposed new 10 CFR 50.221, “Credibility requirements for modeling and simulation.” This shift would enable licensee-led evaluations and allow for the evaluation of advanced modeling methods through structured processes rather than fixed requirements.