05000269/LER-2019-001, Standby Shutdown Facility Reactor Coolant Makeup Pump Oil Suction Tubing Failure
| ML19225C402 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 08/13/2019 |
| From: | Dalton S Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA-19-0335 LER 2019-001-00 | |
| Download: ML19225C402 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 2692019001R00 - NRC Website | |
text
( ~ DUKE ENERGY~
RA-19-0335 August 13, 2019 Attn: Document Control Desk U.S. Nuclear Regulatory Commission 11555 Rockville Pike Rockville, MD 20852-2746 Duke Energy Carolinas, LLC Oconee Nuclear Station Unit 1 Docket Numbers: 50-269 Renewed Operating Licenses: DPR-38 Sheila Dalton Manager, Nuclear Support Services Oconee Nuclear Station Duke Energy ON01SC I 7800 Rochester Hwy Seneca, SC 29672 o. 864.873.3657 f: 864.873.3401 sheila. dalton@duke-energy.com 10 CFR 50.73
Subject:
Licensee Event Report 269/2019-001, Revision 00 - Unit 1 Standby Shutdown Facility Reactor Coolant Makeup Pump Oil Suction Tubing Failure Licensee Event Report 269/2019-001, Revision 00, is being submitted pursuant to the requirements of 10 CFR 50. 73 to provide notification of the subject event.
There are no regulatory commitments associated with this LER.
There are no unresolved corrective actions necessary to restore compliance with NRC requirements.
If there are questions, or further information is needed, contact Sam Adams, Regulatory Affairs, at (864) 873-3348.
Sincerely, Sheila Dalton Manager, Nuclear Support Services Oconee Nuclear Station Enclosure
RA-19-0335 August 13, 2019 Page 2 cc (w/Enclosure):
Ms. Laura Dudes, Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 Ms. Audrey L. Klett, Project Manager (by electronic mail only)
U.S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop O-08B 1 A Rockville, MD 20852-2738 Mr. Adam Ruh NRC Senior Resident Inspector (Acting)
Oconee Nuclear Station
NRCFORM U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES:
366 03/31/2020 (04-2018)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
, 3. Page Oconee Nuclear Station Unit 1 05000269 1 OF4
- 4. Title Unit 1 Standby Shutdown Facility Reactor Coolant Makeup Pump Oil Suction Tubing Failure
- 5. Event Date
- 6. LER Number
- 7. Report Date
- 8. Other Facilities Involved Sequential Rev Facility Name Docket Number Month Day Year Year Month Day Year NA Number No.
05000 11 09 2016 2019 001 00 08 13 2019 Facility Name Docket Number NA 05000
- 9. Operating Mode
- 11. This Reoort is Submitted Pursuant to the Reauirements of 10 CFR §: (Check all that aoolv) 6 0 20.2201(b)
D 20.2203(a)(3)(i) 0 50.73(a)(2)(ii)(A)
D 50. 73(a)(2)(viii)(A) 0 20.2201(d)
D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4)
D 50.73(a)(2)(iii)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(i) 0 50.36(c)(1 )(i)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
- 10. Power Level D 20.2203(a)(2)(ii) 0 50.36(c)(1 )(ii)(A)
D 50.73(a)(2)(v)(A)
D 73.71(a)(4)
D 20.2203(a)(2)(iii)
D 50.36(c)(2)
D 50.73(a)(2)(v)(B)
D 73.71(a)(5) 000 D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50. 73(a)(2)(v)(C)
D 73.77(a)(1)
D 20.2203(a)(2)(v) 0 50. 73(a)(2)(i)(A)
D 50. 73(a)(2)(v)(D)
D 73.77(a)(2)(ii)
D 20.2203(a)(2)(vi) 181 50. 73(a)(2)(i)(B)
D 50.73(a)(2)(vii)
D 73.77(a)(2)(iii) 0 50.73(a)(2)(i)(C)
D Other (Specify in Abstract below or in SEQUENTIAL NUMBER 001 REV NO.
00 Subsequent engineering testing, analysis and evaluation was performed, in May and June of 2019, to review past-operability of the RCM pump with the sheared lube oil suction tube. A reportability evaluation performed by Oconee staff reviewed all of the test, analysis and evaluation results. Oconee staff concluded that the RCM pump could have operated with this degraded condition, however the evaluation could not demonstrate Operability of the pump for the 72-hour mission time without uncertainty.
Therefore, past-operability cannot be conclusively determined and the suction tubing failure on the RCM Pump is being reported as an operation or condition prohibited by TS in accordance with 10 CFR 50.73(a)(2)(i)(B).
CAUSAL FACTORS A cause evaluation was performed in accordance with the Duke Energy Corrective Action Program. The cause evaluation determined that the direct cause of the mechanical interference between the copper oil tubing and rotating shaft components was an incorrect placement and alignment of the tubing when it was installed in the previous refueling outage.
The cause analysis concluded that the root cause was that the work instructions were inadequate in that the PM did not provide instructions for checking and ensuring proper clearance between the rotating shaft components and the tubing.
CORRECTIVE ACTIONS
- 1. The sheared oil suction tubing was replaced.
- 2. The procedures for the performance of the lubrication PM were revised to add task instructions to do a functional verification by hand rotating the pump shaft to ensure no mechanical interferences exist.
SAFETY ANALYSIS
The subject event was evaluated using the Oconee Probabilistic Risk Assessment (PRA) model and found to be of very low safety significance. Although the condition of the RCM pump was degraded and assumed to be inoperable, pump testing and analysis demonstrated that it remained able to perform its design function. The uncertainty associated with the reliability of the RCM pump was evaluated in a sensitivity analysis that determined that the plant core damage frequency would not increase significantly even if the nominal pump run failure probability was significantly increased. Therefore, it is concluded that the risk impact is very low and had no significant impact on public health and safety.
ADDITIONAL INFORMATION
SEQUENTIAL NUMBER 001 REV NO.
00 A review of Duke Energy's Corrective Action Program did not identify any Oconee LERs or events in the last 3 years that involved the same underlying concerns or reasons as this event.
Energy Industry Identification System (EIIS) codes are identified in the text as [XX]. This event is considered INPO Consolidated Events System (ICES) Reportable. There were no releases of radioactive materials, radiation exposures or personnel injuries associated with this event. Page 4 of 4