10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications

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Prohibited by Technical Specifications. LCO time exceeded, including failed testing, maintenance, or analyses.

Reporting criteria referring to 10 CFR 50.73#a2iB:

(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 discovery of the event.

No corresponding 10 CFR 50.72 criteria.

An LER is required for any operation or condition that was prohibited by the plant’s TS, subject to the exceptions stated in the rule. The NRC expects licensees to include violations of the TS in their corrective action programs, which are subject to NRC audit.

LCO 3.0.4

Changing modes or entering the applicability of an LCO when the LCO is an Operation prohibited by TS LCO 3.0.4 and, therefore, reportable as an LER under 10 CFR 50.73(a)(2)(i)(B).

Same criteria as Prohibited by TS except you don't get any completion times or LCO 3.0.3 shutdown times.

Clarified guidance

added examples for entry into TS Limiting Condition for Operation (LCO) 3.0.3 and after-the-fact discovery of conditions

– Entry into LCO 3.0.3 does NOT constitute operation or condition prohibited by TS unless associated shutdown completion times are exceeded (e.g., Modes 3, 4, or 5 for the Westinghouse Standard TS)
– Reportable even if the condition was not discovered until after the completion time had elapsed and the condition was rectified immediately upon discovery
– Other reporting requirements may apply if the condition is not reportable under this criterion

Discussion[1]

Safety Limits and Limiting Safety System Settings

The regulation in 10 CFR 50.36(c)(1) outlines the reporting requirements in TS for events in which safety limits or limiting safety system settings are exceeded. It indicates that such reports are to be made as required by 10 CFR 50.72 and 50.73. There would not be a 3-year limitation in this case because, in addition to the requirements of 10 CFR 50.72 and 50.73, specific reporting requirements are stated in 10 CFR 50.36(c)(1), and perhaps in the plant’s TS.

Limiting Conditions for Operation

The regulation in 10 CFR 50.36(c)(2) outlines LCOs in TS. Certain TS contain LCO statements that include action statements (required actions and their associated completion time in the STS) to provide constraints on the length of time components or systems may remain inoperable or out of service before the plant must shut down or other compensatory measures must be taken. Such time constraints are based on the safety significance of the component or system being removed from service.

An LER is required if a condition existed for a time longer than permitted by the TS (i.e., greater than the total allowed restoration and shutdown outage time (or completion time in the STS)), even if the condition was not discovered until after the allowable time had elapsed and the condition was rectified immediately upon discovery. This guidance is consistent with that previously given. (For the purpose of this discussion, it is assumed that there was firm evidence that a condition prohibited by TS existed before discovery, for a time longer than permitted by TS.)

Technical Specification Surveillance Testing

The regulation in 10 CFR 50.36(c)(3) outlines surveillance requirements in TS that assure (1) the necessary quality of systems and components, (2) operation within safety limits, and (3) meeting the LCOs.

Generally, an operation or condition prohibited by the TS existed and is reportable if surveillance testing indicates that equipment (e.g., one train of a multiple-train system) was not capable of performing its specified safety functions (and thus was inoperable) for a period of time longer than allowed by TS (i.e., the LCO-allowed outage time, or the completion time for restoration of equipment in the STS). Reporting is not required if an event consists solely of a case of a late surveillance test in which the oversight is corrected, the test is performed, and the equipment is found to be capable of performing its specified safety functions.

For the purpose of evaluating the reportability of a discrepancy found during surveillance testing that is required by the TS, licensees should do the following:

(1) For testing that is conducted within the required time (i.e., the surveillance interval plus any extension allowed by STS Surveillance Requirement (SR) 3.0.2 or its equivalent), it should be assumed that the discrepancy occurred at the time of its discovery unless there is firm evidence, based on a review of relevant information such as the equipment history and the cause of failure, to indicate that the discrepancy existed previously.
(2) For testing that is conducted later than the required time, it should be assumed that the discrepancy occurred at the time the testing was required unless there is firm evidence to indicate that it occurred at a different time.

The purpose of this approach is twofold. First, it rules out reporting of routine occurrences (i.e., occurrences for which a timely surveillance test is performed, the results fall outside of acceptable limits, and the condition is corrected) unless there is firm evidence that equipment was incapable of performing its specified safety function longer than allowed. On the other hand, if the surveillance test is performed substantially late, and the equipment is not capable of performing its specified safety function, the occurrence is not routine. In this case, the event is reportable unless there is firm evidence that the duration of the discrepancy was within allowed limits.

For cases in which it is discovered that a surveillance test was not performed within its specified frequency or interval, some plants have TS that allow a delay in declaring an LCO or that TS requirements were not met (i.e., STS SR 3.0.3 or its equivalent). This allows time to perform the test before making such a declaration and taking other required actions. However, an LER would still be required if the test indicates that equipment (e.g., one train of a multiple-train system) was not capable of performing its specified safety functions (and thus was inoperable) for a period of time longer than allowed by TS. The allowed delay in declaring the LCO not met does not change the fact that the condition existed longer than allowed by TS.

Tests Required by Section XI of the American Society of Mechanical Engineers Code In 10 CFR 50.55a(g) and 50.55a(f), the NRC requires the implementation of inservice inspection and inservice testing programs in accordance with the applicable edition of the American Society of Mechanical Engineers (ASME) Code for those pumps and valves whose function is required for safety. The STS contain these testing requirements.

As with surveillance testing, an operation or condition prohibited by the TS existed and is reportable if the testing indicates that equipment (e.g., one train of a multiple-train system required to be operable by the TS) was not capable of performing its specified safety functions (and thus was inoperable) for a period of time longer than allowed by TS. Accordingly, similar assumptions and standards should be used. For example, if a timely test indicates that equipment is not capable of performing its specified safety function, it should be assumed that the discrepancy occurred at the time of the test unless there is firm evidence to indicate that it existed previously.

Design and Analysis Defects and Deviations

A design or analysis defect or deviation is reportable under this criterion if, as a result, equipment (e.g., one train of a multiple-train system) was not capable of performing its specified safety functions (and thus was inoperable) for a period of time longer than allowed by TS. Because design and analysis conditions are long lasting, the essential question in this case is whether the equipment was capable of performing its specified safety functions.

Administrative Requirements

Section 5 of the STS, or its equivalent, has a number of administrative requirements, such as organizational structure, the required number of personnel on shift, the maximum hours of work permitted during a specific interval of time, and the requirement to have, maintain, and implement certain specified procedures. Violation of a TS that is administrative in nature is not reportable.

For example, a change in the plant’s organizational structure that has not yet been approved as a TS change would not be reportable. An administrative procedure violation, or failure to implement a procedure, such as failure to lock a high-radiation-area door, is generally not reportable under this criterion. Radiological conditions and events that are reportable are defined in 10 CFR 20.2202, “Notification of Incidents,” and 10 CFR 20.2203, “Reports of Exposures, Radiation Levels, and Concentrations of Radioactive Material Exceeding the Constraints or Limits.” Redundant reporting is not required.

Entry into STS 3.0.3

STS LCO 3.0.3, or its equivalent, establishes requirements for actions when (1) an LCO is not met and the associated actions are not met, (2) an associated action is not provided, or (3) as directed by the associated actions themselves.

Entry into LCO 3.0.3 or its equivalent is not necessarily reportable under this criterion. However, it should be considered reportable under this criterion if any of the shutdown times listed in LCO 3.0.3 (e.g., Modes 3, 4, or 5 for the Westinghouse STS) were exceeded, even if the condition was not discovered until after the allowable time had elapsed and the condition was rectified immediately upon discovery.

For a given LCO condition, if shutdown required actions and completion times are listed (e.g., be in hot shutdown in X hours and cold shutdown in Y hours), shutdown times associated with LCO 3.0.3 should not be considered (i.e., only consider LCO action table shutdown completion time added to restorative completion time when determining if “Operations or Conditions Prohibited by Technical Specifications” existed). If entry into LCO 3.0.3 is explicitly listed as a required action for a given condition, or for cases in which the condition is not listed in the action table, shutdown times associated with LCO 3.0.3 may be added to any associated restorative completion times found in the action table when determining if “Operations or Conditions Prohibited by Technical Specifications” existed.

The discussion contained in this section only pertains to “Operations or Conditions Prohibited by Technical Specifications.” Entry into LCO 3.0.3 may still result in other reportable conditions under 10 CFR 50.72 and 50.73.

Revised Technical Specifications

An LER is not required for discovery of an operation or condition that occurred in the past and was prohibited at the time it occurred if, before the time of discovery, the TS were revised such that the operation or condition is no longer prohibited. Such an event would have little or no significance because the operation or condition would have been determined to be acceptable and allowed under the current TS.

Examples

(1) Limiting Condition for Operation Exceeded

In conducting a timely 30-day surveillance test, a licensee found a standby component with a 7-day LCO-allowed outage time and an associated 8-hour shutdown action statement to be inoperable. (This is equivalent to a 7-day restoration completion time and an 8-hour action completion time in the STS.) Subsequent review indicated that the component was assembled improperly during maintenance conducted 30 days previously and the post maintenance test was not adequate to identify the error. Thus, there was firm evidence that the standby component had been inoperable for the entire 30 days.

An LER was required because the condition existed longer than allowed by the TS (the 7-day LCO-allowed outage time and the shutdown action statement time of 8 hours). Had the inoperability been identified and corrected within the required time, the event would not be reportable.

(2) Late Surveillance Tests

A licensee, with the plant in Mode 5 following a 10-month refueling outage, determined that certain monthly TS surveillance tests, which were required to be performed regardless of plant mode, had not been performed as required during the outage. The STS SR 3.0.2 extension was also exceeded. The surveillance tests were immediately performed.

No LER would be required if the tests showed the equipment was still capable of performing its specified safety functions. On the other hand, if the tests showed the equipment was not capable of performing its specified safety functions (and thus was inoperable) in excess of the allowed time, the event would be reportable.

(3) Multiple Test Failures

An example of multiple test failures involves the sequential testing of safety valves.

Sometimes multiple valves are found to lift with setpoints outside of TS limits.

As discussed above, discrepancies found in TS surveillance tests should be assumed to occur at the time of the test unless there is firm evidence, based on a review of relevant information (e.g., the equipment history and the cause of failure), to indicate that the discrepancy occurred earlier. However, the existence of similar discrepancies in multiple valves is an indication that the discrepancies may well have arisen over a period of time and that the failure mode should be evaluated to make this determination. If so, the condition existed during plant operation and the event is reportable under 10 CFR 50.73(a)(2)(i)(B) (“Any operation or condition prohibited by the plant’s Technical Specifications”).

If the discrepancies are large enough that multiple valves are inoperable, the event may also be reportable under the following criterion in 10 CFR 50.73(a)(2)(vii): “Any event where a single cause or condition caused at least one independent train or channel to become inoperable in multiple systems or two independent trains or channels to become inoperable in a single system.”

(4) Seismic Restraints

Assume it is found that an exciter panel for one EDG had lacked appropriate seismic restraints since the plant was constructed because of a design, analysis, or construction inadequacy. Upon evaluation, the EDG is determined to be inoperable because it is not capable of performing its specified safety functions during and after safe-shutdown earthquake.

An LER would be required because the EDG was inoperable for a period of time longer than allowed by TS.

(5) Vulnerability to Loss of Offsite Power

Assume that during a design review it is found that a loss of offsite power could cause a loss of instrument air and, as a result, auxiliary feedwater (AFW) flow control valves could fail open. Therefore, for low steam generator pressure such as could occur for certain main steamline breaks, high AFW flow rates could result in tripping the motor-driven AFW pumps on thermal overload. Therefore, the motor-driven AFW pumps are determined to be inoperable. The single turbine-driven AFW pump is not affected.

An LER would be required because the motor-driven portion of AFW was inoperable for a period of time longer than allowed by the TS.

(6) Entry into STS 3.0.3

The following two examples illustrate the “Entry into STS 3.0.3” discussions. Both examples use STS 3.5.1, “Accumulators” found in Westinghouse STS, Revision 4, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12100A222), and assumes historic and current operations in Mode 1.

(a) One accumulator inoperable due to boron concentration not within limits

When evaluating if an Operation or Condition Prohibited by TS occurred, the timeframe to consider is the total time allowed by Condition A (restorative Completion Time) added to Condition C (shutdown Completion Time). Condition A, “One accumulator inoperable due to boron concentration not within limits,” has a Completion Time of 72 hours, while Condition C, “Required Action and associated Completion Time of Condition A or B not met,” has a Completion Time of 6 hours to be in Mode 3. If it is determined that one accumulator was inoperable due to boron concentration not within limits for greater than 78 hours (72 hour restorative Completion Time added to 6 hour shutdown Completion Time), then an Operation or Condition Prohibited by TS existed. The condition would be reportable even if the condition was not discovered until after the allowable time had elapsed and the condition was rectified immediately upon discovery. Since the Action table contains shutdown required actions and completion times for the given condition, times associated with LCO 3.0.3 are not considered.

(b) Two or more accumulators inoperable

When evaluating if an Operation or Condition Prohibited by TS occurred, the timeframe to consider is the total time allowed by Condition D (restorative Completion Time) added to the shutdown time associated with LCO 3.0.3. Condition D, “Two or more Accumulators inoperable,” has a Completion Time of Immediately and LCO 3.0.3 requires that the unit be in Mode 3 within 7 hours. If it is determined that two or more accumulators were inoperable for greater than 7 hours (Immediate restorative Completion Time added to 7 hour shutdown time), then an Operation or Condition Prohibited by TS existed. The condition would be reportable even if the condition was not discovered until after the allowable time had elapsed and the condition was rectified immediately upon discovery.

(7) Laboratory Testing of Charcoal Adsorbers

The following example illustrates a scenario in which the results of testing required by the TS are available at a later time. The example uses STS 3.7.10, “Control Room Emergency Filtration System (CREFS)” found in Westinghouse STS, Revision 4, (ADAMS Accession No. ML12100A222).

While operating in Mode 1, SR 3.7.10.2 is performed on two CREFS filter trains. SR 3.7.10.2 requires CREFS filter testing in accordance with the Ventilation Filter Testing Program (VFTP) found in TS 5.5.11. Part c of the VFTP requires laboratory testing of charcoal adsorber samples. On Day 1, the licensee takes samples and sends it out to a laboratory for analysis. The plant continues to operate in Mode 1. On Day 20, the licensee gets back the results that indicate that the methyl iodide penetration is greater than the value specified in TS 5.5.11.c for one of the filter trains. The licensee then declares the effected CREFS train inoperable. As stated in the Discussion Section above, an Operation or Condition Prohibited by TS can exist even if the condition was not discovered until after the allowable time had elapsed and the condition was rectified immediately upon discovery. When evaluating if an Operation or Condition Prohibited by TS occurred, the timeframe to consider is the total time allowed by Condition A (restorative Completion Time) added to Condition C (shutdown Completion Time). Condition A, “One CREFS train inoperable for reasons other than Condition B {inoperable boundary},” has a Completion Time of 7 days and Condition C, “Required Action and associated Completion Time of Condition A or B not met…” has a Completion Time of 6 hours to be in Mode 3.

Since the inoperable condition on the effected CREFS train existed for at least 20 days, an Operation or Condition Prohibited by TS existed (i.e., the inoperable condition exceeded the combined 7 day restorative Completion Time added to the 6 hour shutdown Completion Time), The discussions found in this example would still be relevant even if plant specific TS provide additional restrictions on when the test sample must be received back from the laboratory (i.e. verify results within 31 days after sample removal, etc).

LERs submitted under this criterion

  1. This criterion does not address violations of license conditions that are contained in documents other than the TS. Such violations are reportable as specified in the plant’s license or other applicable documents.