ML18136A776
| ML18136A776 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 05/16/2018 |
| From: | NRC/RGN-II |
| To: | |
| References | |
| Download: ML18136A776 (2) | |
Text
McGuire Nuclear Station 2018 NRC Exam Post-Exam Comments Operating Exam After conducting a post-examination review of the 2018 MNS NRC Operating Examination, two items were identified that required post examination comments:
Scenario #1, Event 3 1A S/G Tube Leak During administration of Scenario #1 of the operating exam, an approximate 30 GPM S/G Tube Leak on 1A S/G was given to the applicants. The original submittal identified Tech Spec 3.4.13 (RCS Operational Leakage) condition B and SLC 16-9.7 (Standby Shutdown System (SSS)) conditions A and C as being the applicable Tech Specs and SLCs for this failure. It has since been determined that Tech Spec 3.4.18 (SG Tube Integrity) Condition B is also applicable for this particular scenario. The following information is from the Tech Spec 3.4.18 Bases:
A SG tube has tube integrity when it satisfies the SG performance criteria. The SG performance criteria are defined in Specification 5.5.9, Steam Generator (SG) Program, and describe acceptable SG tube performance. The Steam Generator Program also provides the evaluation process for determining conformance with the SG performance criteria.
There are three SG performance criteria: structural integrity, accident induced leakage, and operational LEAKAGE. Failure to meet any one of these criteria is considered failure to meet the LCO.
Based on the fact that the operational LEAKAGE for this scenario exceeded the limit of 135 Gallons Per Day identified in Tech Spec 3.4.13, it is the opinion of the station (Operations Management) that Tech Spec 3.4.18 LCO is also not met, and that Condition B is applicable.
Resolution: Request the applicable ES-D-2 be updated to include required application of T.S. 3.4.18 Condition B following the 1B S/G Tube Leak.
McGuire Nuclear Station 2018 NRC Exam Post-Exam Comments Systems (Control Room) JPM "B" (Align the Containment Spray System to Cold leg Recirculation): mis-operation of 1NS-20A Explanation:
The Task Standard for Systems-Control Room JPM "B" is as follows:
"The operator will attempt to align the 1A NS Pump for operation until it is observed that 1NS-18A has failed to open. The operator will then align the 1B NS Train for operation, and secure the 1A NS Train operation".
One applicant mis-operated valve 1NS-20A in Step 8.e.6 "check 1NS-20A -
CLOSED" of ES-1.3 (Transfer To Cold Leg Recirc).
Step 8.e.6 of ES-1.3 states "check 1NS-20A - CLOSED". If the valve were to be open when "checked", the correct action would be to go to the RNO and GO TO step 8.f to align B train NS to the sump. This is the flow path the applicant pursued after the mis-operation.
1NS-18A is interlocked with 1NS-20A. 1NS-20A must be closed to allow 1NS-18A to open. Therefore, 1NS-18A would not have opened, if attempted, in step 8.e.7 of ES-1.3. No alignment could be made that would connect the containment sump to the FWST.
Step 8g and 8g RNO of ES-1.3 addresses NS Train A not being available and places an info sticker on the containment sump valve and closes the NS Train A discharge valves to isolate the A train flow path.
Resolution:
The facility endorsed position is that there were no system/plant consequences as a result of the mis-operation of 1NS-20A and the task standard to align B Train of NS for recirculation was achieved.