(a) Reportable events.

1. (1) Each commercial nuclear plant licensee holding an OL under this part or a COL under this part after the Commission makes the finding under § 53.1452(g), must submit a Licensee Event Report (LER) for any event of the type described in this paragraph (a) within 60 days after discovery of the event. In the case of an invalid actuation reported under § 53.1640(a)(2), other than automatic reactor shutdown when the reactor is critical, the licensee may, at its option, provide a telephone notification to the NRC Operations Center within 60 days after discovery of the event instead of submitting a written LER. Unless otherwise specified in this section, the licensee must report an event if it occurred within 3 years of the date of discovery regardless of the plant mode or power level, and regardless of the significance of the structure, system, or component that initiated the event.

2. (2) The licensee must report—

   1. (i)

      1. (A) The completion of any commercial nuclear plant shutdown required by the plant's Technical Specifications.

      2. (B) Any operation or condition which was prohibited by the plant's Technical Specifications except when—

         (1) The Technical Specification is administrative in nature;

         (2) The event consisted solely of a case of a late surveillance test where the oversight was corrected, the test was performed, and the equipment was found to be capable of performing its specified safety functions; or

         (3) The Technical Specification was revised prior to discovery of the event such that the operation or condition was no longer prohibited at the time of the event.

      3. (C) Any deviation from the plant's Technical Specifications authorized under § 53.740(h).

   2. (ii) Any event or condition that resulted in—

      1. (A) The condition of the commercial nuclear plant, including its principal safety barriers, being seriously degraded; or
      2. (B) The commercial nuclear plant being in a condition not analyzed under § 53.450 that significantly degrades plant safety.
   3. (iii) Any natural phenomena or other external condition that posed an actual threat to the safety of the commercial nuclear plant or significantly hampered site personnel in the performance of duties necessary for the safe operation of the commercial nuclear plant.

   4. (iv) Any event or condition that resulted in inadvertent operation of any structures, systems, and component classified as safety-related (SR) for an identified safety function under § 53.460 or the unplanned sole reliance on an SR system for those systems that are in constant operation, except when—

      1. (A) The actuation resulted from and was part of a pre-planned sequence during testing; or

      2. (B) The actuation was invalid and—

         (1) Occurred while the system was properly removed from service; or

         (2) Occurred after the safety function had been already completed.

   5. (v) Any event or condition that could have prevented the fulfillment of the safety functions identified under § 53.230.
   6. (vi) Events covered in paragraph (a)(2)(v) of this section may include one or more procedural errors, equipment failures, and/or discovery of design, fabrication, construction, and/or procedural inadequacies. However, individual component failures need not be reported pursuant to paragraph (a)(2)(v) of this section if any other equipment was operable and available to perform the required safety function.

   7. (vii)

      1. (A) Any event or condition that as a result of a single cause could have prevented the fulfillment of any of the safety functions identified under § 53.230.

      2. (B) Events covered in paragraph (a)(2)(vii)(A) of this section may include cases of procedural error, equipment failure, and/or discovery of a design, analysis, fabrication, construction, and/or procedural inadequacy. However, licensees are not required to report an event pursuant to paragraph (a)(2)(vii)(A) of this section if the event results from—

         (1) A shared dependency among trains or channels that is a natural or expected consequence of the approved plant design; or

         (2) Normal and expected wear or degradation.

   8. (viii)

      1. (A) Any airborne radioactive release that, when averaged over a time period of 1-hour, resulted in airborne radionuclide concentrations in an unrestricted area that exceeds 20 times the applicable concentration limits specified in appendix B to 10 CFR part 20, table 2, column 1.
      2. (B) Any liquid effluent release that, when averaged over a time period of 1-hour, exceeds 20 times the applicable concentrations specified in appendix B to 10 CFR part 20, table 2, column 2, at the point of entry into the receiving waters (i.e., unrestricted area) for all radionuclides except tritium and dissolved noble gases.
   9. (ix) Any event that posed an actual threat to the safety of the commercial nuclear plant or significantly hampered site personnel in the performance of duties necessary for the safe operation of the plant, including fires, toxic gas releases, or radioactive releases.

(b) Contents. The LER must contain—

1. (1) A brief abstract describing the major occurrences during the event, including all component or system failures that contributed to the event and significant corrective action taken or planned to prevent recurrence.

2. (2)

   1. (i) A clear, specific narrative description of what occurred so that knowledgeable readers conversant with the design of commercial nuclear plants, but not familiar with the details of a particular plant, can understand the complete event.

   2. (ii) The narrative description must include the following specific information as appropriate for the particular event:

      1. (A) Plant operating conditions before the event.
      2. (B) Status of systems, structures, or components that were inoperable at the start of the event and that contributed to the event.
      3. (C) Dates and approximate time of the occurrences.
      4. (D) The cause of each component or system failure or personnel error, if known.
      5. (E) The failure mode, mechanism, and effect of each failed component, if known.
      6. (F) [Reserved]
      7. (G) For failures of components with multiple functions, include a list of systems or secondary functions that were also affected.
      8. (H) For failure that rendered a component or system classified as SR or non-safety-related but safety-significant inoperable, an estimate of the elapsed time from the discovery of the failure until the component or system was returned to service.
      9. (I) The method of discovery of each component or system failure or procedural error.
      10. (J) For each human performance related root cause, the licensee must discuss the cause(s) and circumstances.
      11. (K) Automatically and manually initiated safety system responses.
      12. (L) The manufacturer and model number (or other identification) of each component that failed during the event.

3. (3) An assessment of the safety consequences and implications of the event. This assessment must include—

   1. (i) The availability of systems or components that could have performed the same function as the components and systems that failed during the event, and
   2. (ii) For events that occurred when the reactor was shut down, the availability of systems or components that are needed to shut down the reactor and maintain safe shutdown conditions, remove residual heat, control the release of radioactive material, or mitigate the consequences of an accident.
4. (4) A description of any corrective actions planned as a result of the event, including those to reduce the probability of similar events occurring in the future.
5. (5) Reference to any previous similar events at the same plant that are known to the licensee.
6. (6) The name and contact information of a person within the licensee's organization who is knowledgeable about the event and can provide additional information concerning the event and the plant's characteristics.