05000395/LER-2016-004-01, Regarding Steam Propagation Barrier Degrade Due to Missing Orifices
ML17033B592 | |
Person / Time | |
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Site: | Summer ![]() |
Issue date: | 02/01/2017 |
From: | Lippard G South Carolina Electric & Gas Co |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
LER 16-004-01 | |
Download: ML17033B592 (7) | |
Event date: | |
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Report date: | |
Reporting criterion: | 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 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)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) |
3952016004R01 - NRC Website | |
text
George A. Lippard Vice President, Nuclear Operations 803.345.4810 February 1, 2017 A SCANA COMPANY Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555
Dear Sir / Madam:
Subject:
VIRGIL C. SUMMER NUCLEAR STATION (VCSNS), UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSEE EVENT REPORT (LER 2016-004-01)
STEAM PROPAGATION BARRIER DEGRADED DUE TO MISSING ORIFICES Attached is Licensee Event Report (LER) 2016-004-01, for the Virgil C. Summer Nuclear Station. This revised report supplements LER 2016-004-00. This report describes an event that was identified based on an extent of condition review for LER 2016-003-00 Steam Propagation Door (DRIB/107) Discovered Propped Open. The station identified orifices that were not installed in the correct drain lines as specified in a design change package. The station has completed an evaluation of the impacted areas if a High Energy Line Break (HELB) event occurred. This report is submitted in accordance with 10CFR50.73(a)(2)(v)(D) and 10CFR50.73(a)(2)(i)(B).
Should you have any questions, please call Mr. Bruce Thompson at (803) 931-5042.
Very truly yours BAB/GAL/ts Attachment c:
K. B. Marsh S. A. Williams S. A. Byrne NRC Resident J. B. Archie Inspector N. S. Cams L. W. Harris J. H. Hamilton Paulette Ledbetter S. M. Shealy J. C. Mellette W. M. Cherry ICES Coordinator C. Haney K. M. Sutton Marsh USA, Inc.
Maintenance Rule Engineer NSRC RTS (CR-16-04716 & CR-16-04801)
File (818.07)
PRSF (RC-17-0021)
INPO Records Center V. C. Summer Nuclear Station
- P. 0. Box 88
- Jenkinsville, SC
- 29065
- F (803) 941-9776
NRC FORM 366 (06-2016)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
(See Page 2 for required number of digits/characters for each block)
(See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nureas/staff/sr1022/r3/)
APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.
Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the FOIA, Privacy and Information Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME VC SUMMER-UNIT 1
- 2. DOCKET NUMBER 05000 395
- 3. PAGE 1 OF
- 4. TITLE STEAM PROPAGATION BARRIER DEGRADE DUE TO MISSING ORIFICES
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR Y
SEQUENTIAL REV NUMBER NO.
MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 05000 09 14 2016 2016 -
004 01 02 01 2017 FACILITY NAME DOCKET NUMBER 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 1 l l 20.2201(b) 20.2203(a)(3)(i) 50.73(a) (2) (ii)(A) 50.73(a) (2)(viii)(A) 1
]
20.2201(d) 7] 20.2203(a)(3)(ii) 50.73(a) (2)(ii)(B) 50.73(a) (2)(viii)(B) 1 Q 20.2203(a)(1) l l 20.2203(a)(4) 50.73(a) (2)(iii) 50.73(a)(2)(ix)(A) 1 3] 20.2203(a)(2)(i) 50.36(c)(1 )(i)(A) 50.73(a) (2)(iv)(A) 50.73(a)(2)(x)
- 10. POWER LEVEL 100
]
20.2203(a)(2)(ii) 50.36(c)(1 )(ii)(A) 50.73(a)(2)(v)(A) 73.71(a)(4)
- 10. POWER LEVEL 100
]
20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(B) 73.71(a)(5)
- 10. POWER LEVEL 100
] 20.2203(a)(2)(iv) 50.46(a)(3)(H) 50.73(a)(2)(v)(C) 73.77(a)(1)
- 10. POWER LEVEL 100 2 20.2203(a)(2)(v) 50.73(a)(2)(i)(A)
\\7\\ 50.73(a)(2)(v)(D) 73.77(a) (2) (i)
- 10. POWER LEVEL 100
] 20.2203(a)(2)(vi)
[7] 50.73(a)(2) (i) (B) 50.73(a) (2) (vii) 73.77(a) (2) (ii)
- 10. POWER LEVEL 100 50.73(a)(2)(i)(C)
~l OTHER Specify in Abstract below or in =
Root Cause (RC02): The work order steps for installing the orifice plates were classified as non-nuclear safety related work. When QC reviewed the work order, they determined that no QC was necessary based on the work order safety classification. However, the ECR classified this work as Quality Related. This resulted in the orifice installation being performed without QC verification. No guidance existed at the time the work orders were planned that would have instructed QC inspectors to review ECR packages for safety classification during the QC work order routing reviews.
Potential Root Cause (RC03): The potential exists that the information (ECR section) included in the work package was not sufficient to provide adequate work instruction. If the ECR instructions were not included in the work package, the information available to the workers for the orifice plate installation locations was inadequate. The detailed drawing, included in the work package, was incorrect for the "A" Chiller orifice plate location. Due to this occurring over seven years previous, the workers could not recall what led up to or contributed to the orifice plates being located in the wrong location. Neither the planner nor the workers could recall whether or not the ECR section was included in the work package.
Potential Root Cause (RC04): The potential exists that the workers failed to follow work (ECR) instructions if it had been included in the work package. The ECR written instructions provided sufficient detail for the orifice plates to be installed in the correct locations. If the ECR was included in the work package, the workers would have had adequate work instructions, but failed to follow it. The Work Order instructions available to the workers did not include the room numbers.
Due to this occurring over seven years previous, the workers could not recall what led up to or contributed to the orifice plates being located in the wrong location. Neither the planner nor the workers could recall whether or not the ECR section was included in the work package.
Contributing Cause (CC1): The interface review comments were provided but were not resolved in a manner to aid in determining proper installation locations per the drawings. There were two comments made during the ECR interface review that would have clarified the orifice plate installation locations. A promissory resolution was given to an incorrect drawing and the second comment on the clarity of the orifice plate locations was dismissed with no resolution. There was no formal tracking in place for the resolution of interface review comments. As a result, the information provided in the ECR lacked clarity.
Contributing Cause (CC2): No guidance existed at the time the work orders were planned that would have directed the planner to base safety classification on ECR information. This resulted in the planner basing the non-nuclear safety classification on the CMMS system listing for floor drains instead of the quality related classification of the ECR.
The root cause analysis determined that the causes associate with this event did not reflect current performance.
Corrective actions to address the causes in RCA-16-04801 are addressed in CR-16-04801.
The VU System provides cooling to safety related areas (TS Table 3.7-7) as an attendant cooling system and supports the comfort requirements for the Control Room Emergency Filtration Systems (CREFS). The VU System is needed to ensure that equipment located within these areas can withstand the environmental effects of a postulated FSAR Chapter 15 event. With a nonfunctional chiller unit, its associated VU train will become nonfunctional, thereby affecting room temperatures and the reliability of the train's associated equipment. The most limiting area for temperature limits has been identified as the charging pump rooms. Per TS 3/4.5.2, one charging pump has to be operable per train of Emergency Core Cooling System (ECCS) during Mode 1-3.
Corrective Actions to address the causes in RCA-16-04801 are addressed in CR-16-04801.
5.0 CORRECTIVE ACTIONS
Immediate action taken: On September 14, 2016, stopped all associated VU chiller work and ensured all steam propagation doors were closed. Station Order 16-05 was issued that directs that no work can be performed in the chiller rooms that would require the door(s) to be propped open. The Station Order was in place until the orifice installations in the sumps was corrected.
Interim action taken: On September 21, 2016, Nonconformance (NC)-16-04716-005 Repair Disposition #1 was issued to correctly install the orifice plates. This work was completed on October 6, 2016. Page 6
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