ML24074A272
| ML24074A272 | |
| Person / Time | |
|---|---|
| Issue date: | 03/21/2024 |
| From: | Lundy Pressley NRC/NRR/DRA/APOB |
| To: | |
| References | |
| Download: ML24074A272 (1) | |
Text
Example 1:
Utility admin procedure high-level requirement stating: Configuration control of the plant PRA Models SHALL be maintained.
Relevant IP Step:
03.02.a.1 Review PCC related administrative procedures to ensure that PCC processes are in place and are being followed.
Example Analysis:
This step is open to interpretation due to the timing aspect.
A plant change that has not been evaluated or incorporated into the model at the time the change is implemented into the plant may be considered a non-compliance of our procedure and a performance deficiency.
A plant change that was evaluated and incorporated/not incorporated into the model without documentation that meets the PRA Standard may be considered an issue of concern Enforcement:
No PD - Issue was only the result of inadequate documentation of the basis for the change, and utility has processes for tracking/incorporation of plant changes and can describe the basis for incorporating/not incorporating OR change is tracked for future evaluation.
Minor - Documentation is an issue of concern and our process did not ensure impacts to the PRA receive evaluation/documentation. Cornerstone not adversely impacted.
MTM (more than minor) - Change that wasnt evaluated or incorporated adversely affected an associated cornerstone; significance depends on risk and exposure time.
Example 2:
Utility admin procedure step that states: ensure common-backbone model (CBM) logic changes are checked for proper impact to other hazards.
Relevant IP Step:
03.03 Verify processes and procedures were completed appropriately to ensure the PRA program was being sufficiently maintained to support past and current Risk-Informed decisions.
Example Analysis:
The utility conducted a specific hazard PRA update at a site and the internal events model was impacted in an unexpected way, which was found after model signoff during the MSPI update. This may be considered a performance deficiency.
Enforcement:
No PD - Licensee identified the issue prior to inspection or use for any application and initiated corrective action commensurate with risk impact per procedures, error not systematic or systematic issue corrected.
Minor - Issue was NRC-identified, the impact can be shown to be of negligible impact and the utility initiated corrective action OR issue was licensee identified and corrective action initiated after use for Risk-Informed decisions.
MTM - NRC or licensee identified after use for Risk-Informed decisions and the issue cannot be shown to be of negligible impact; actual impact to cornerstone (e.g. actual MSPI margin not understood and exceeded due to error, actual maintenance rule/RICT evaluations impacted); significance depends on risk and exposure time.
Example 3:
Utility admin procedure step that states:continuous monitoring of PRA inputs against various changes (e.g., plant changes, change in state of knowledge, methodology changes Relevant IP Step:
03.02.a.1 Review PCC related administrative procedures to ensure that PCC processes are in place and are being followed.
Example Analysis:
Failure to include newly released industry guidance, or significant information, in the model log for tracking, or failure to document/disposition the guidance, may be considered an issue of concern Enforcement:
No PD - Issue is being tracked for evaluation and incorporation/non-incorporation. PRA models not impacted (or insignificantly impacted) or the information was not applicable as dispositioned.
Minor - New information was not tracked for evaluation, but PRA models could be impacted by the new information or not adequately dispositioned/documented.