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Proactive Management of Materials Degradation

photos of degraded material

Welcome to the U.S. Nuclear Regulatory Commission Program on Proactive Management of Materials Degradation (PMMD) for LWRs. The NRC has initiated a new program to promote the understanding and use of PMMD methods and technology in extending the life of LWRs. The program will build national and international collaboration on regulatory research issues. The goal of PMMD activities over the next five years is to place NRC in a position where it has the technical basis to answer some key aging-related degradation questions, including:

  • Can licensees safely extend the operating life of existing NPPs to 60-80 years and potentially longer?
  • What are the key technical and regulatory issues that require attention to enable license extension?
  • What information is needed to position NRC to adequately process and respond to applications for a second (and subsequent) license extension?
  • What are the remaining open technical and regulatory issues?

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