05000458/LER-2012-001, Regarding Operations Prohibited by Technical Specifications Due to Inoperability of Division 3 Diesel Generator
| ML12198A002 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 07/09/2012 |
| From: | Olson E Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RBF1-12-0086, RBG-47260 LER 12-001-00 | |
| Download: ML12198A002 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i) 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 4582012001R00 - NRC Website | |
text
wEntergy Entergy Operations, Inc.
River Bend Station 5485 U. S. Highway 61 N St. Francisville, LA 70775 Tel 225 381 4374 Fax 225 381 4872 eolson@entergy.comn Eric W. Olson Site Vice President RBG-47260 July 9, 2012 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555
Subject:
Licensee Event Report 50-458 / 2012-001-00 River Bend Station - Unit 1 Docket No. 50-458 License No. NPF-47 RBF1 0086
Dear Sir or Madam:
In accordance with 10 CFR 50.73, enclosed is the subject Licensee Event Report.
This document contains no commitments. If you have any questions, please contact Mr. Joseph Clark at 225-381-4177.
Sincerely, EWO/dhw Enclosure j69
Licensee Event Report 50-458 / 2012-001-00 July 9, 2012 RBG-47260 RBF1 0086 Page 2 of 2 cc:
U. S. Nuclear Regulatory Commission Region IV 1600 East Lamar Blvd.
Arlington, TX 76011-4511 NRC Sr. Resident Inspector P. O. Box 1050 St. Francisville, LA 70775 INPO Records Center E-Mail (MS Word format)
Ms. Tracie Lowery Public Utility Commission of Texas 1701 N. Congress Ave.
Austin, TX 78711-3326 Department of Environmental Quality Office of Environmental Compliance Radiological Emergency Planning and Response Section JiYoung Wiley P.O. Box 4312 Baton Rouge, LA 70821-4312
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013 (10-2010) digits/characters for each block) the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE River Bend Station - Unit 1 05000-458 1 OF 3
- 4. TITLE Operations Prohibited by Technical Specifications Due to Inoperability of Division 3 Diesel Generator
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED I R FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR 1SEQUENTIAL REV MONTH DY EA MN NUMBER NO.
05000 FACILITY NAME DOCKET NUMBER 05 08 2012 2012-001-00 07 09 2012 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
EZ 20.2201(b)
EZ 20.2203(a)(3)(i)
E] 50.73(a)(2)(i)(C)
[E 50:73(a)(2)(vii) 2 El 20.2201(d)
El 20.2203(a)(3)(ii)
EZ 50.73(a)(2)(ii)(A)
E] 50.73(a)(2)(viii)(A)
[] 20.2203(a)(1)
[] 20.2203(a)(4)
[] 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
EZ 20.2203(a)(2)(i)
Z 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
[I 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL
[] 20.2203(a)(2)(ii)
EZ 50.36(c)(1)(ii)(A)
[I 50.73(a)(2)(iv)(A)
[] 50.73(a)(2)(x)
LI 20.2203(a)(2)(iii)
[: 50.36(c)(2)
[: 50.73(a)(2)(v)(A)
LI 73.71 (a)(4)
<5 El 20.2203(a)(2)(iv)
[: 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
LI 73.71 (a)(5)
E] 20.2203(a)(2)(v)
L-50.73(a)(2)(i)(A)
El 50.73(a)(2)(v)(C)
E] OTHER LI 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in NRC Form 366A
- 12. LICENSEE CONTACT FOR THIS LER FACILITY NAME TELEPHONE NUMBER (Include Area Code)
Joseph A. Clark, Manager - Licensing 225-381-4177CAUSE SYSTEM COMPONENT MANU-REPORTABLE FSP MANCU-REPORTABLE FACTURER TO EPIX 4
CAUSE
SYSTEM COMPONENT MANURER EPIX n/a
- 14. SUPPLEMENTAL REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR SUBMISSION 09 28 2012 EYES (If yes, complete 15. EXPECTED SUBMISSION DATE) LI NO DATE ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)
On May 8, 2012, plant engineers confirmed that the lubricating oil in the Division 3 diesel generator (DG) was contaminated with fuel at a level that required its replacement. At the time of this discovery, a plant heat-up was in progress in preparation for return to service following a maintenance outage. The oil sample that yielded these results had been drawn on April 28, and shipped off-site for vendor analysis. Plant engineers evaluated the trends of prior lubricating oil samples taken prior to May 8, and determined that the DG had become incapable of running for the full 30 days assumed by its design safety function on approximately October 28, 2011. It was concluded that this date was the likely starting point of the internal fuel leak that contaminated the oil. On May 8, the DG was removed from service in order to change the lubricating oil and repair the fuel leak.
The investigation of this event determined that the fuel leak was likely due to gasket damage that occurred during the maintenance outage in October 2011. This condition is being reported in accordance with 1 OCFR50.73(a)(2)(i)(B) as operations prohibited by Technical Specifications.
NRC FORM 366 (10-2010)LICENSEE EVENT REPORT (LER)
U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
CONTINUATION SHEET
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE YEAR SEQUENTIAL REV.
NUMBER NO.
River Bend Station - Unit 1 05000 -458 2 OF 3 2012 -- 001 -- 00 REPORTED CONDITION On May 8, 2012, plant engineers confirmed that the lubricating oil in the Division 3 diesel generator (DG) was contaminated with fuel at a level that required its replacement. At the time of this discovery, a plant heat-up was in progress in preparation for return to service following a maintenance outage.
The oil sample that yielded these results had been drawn on April 28, and shipped off-site for vendor analysis. Plant engineers evaluated the trends of prior lubricating oil samples taken prior to May 8, and determined that the DG had become incapable of running for the full 30 days assumed by its design safety function on approximately October 28, 2011. It was concluded that this date was the likely starting point of the internal fuel leak that contaminated the oil.
On May 8, the DG was removed from service in order to change the lubricating oil and repair the fuel leak.
This condition is being reported in accordance with 10CFR50.73(a)(2)(i)(B) as operations prohibited by Technical Specifications.
INVESTIGATION and CAUSAL ANALYSIS The Division 3 DG is an Electro-Motive Division (EMD) Model No. 20-645-E4. Many of the fuel system components are located internally, such that any fuel leakage will likely migrate to the oil sump.
The specified oil viscosity for this engine is 40 weight. Fuel dilution of approximately 5% thins the oil such that the viscosity becomes similar to 30 weight. EMD instructions direct that the engine must not be run with oil contamination greater than 5%. The sample drawn on April 25 contained approximately 4.29% fuel.
In October 2011, the DG was removed from service for scheduled maintenance, including removal and testing of the fuel injectors. Following re-installation of the injectors, a fuel system visual leak test confirmed that no leaks were present.
After the DG was removed from service on May 8, a fuel leak was found at the jumper-to-filter cap connection on number 20 cylinder. The jumper was replaced, and a leak test was performed. The leak rate was reduced, but was not eliminated. The jumper was again removed,LICENSEE EVENT REPORT (LER)
U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
CONTINUATION SHEET
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE YEAR SEQUENTIAL REV.
NUMBER NO.
River Bend Station - Unit 1 05000 -458 3 OF 3 2012 -- 001 -- 00 While observing maintenance technicians performing the work, the system engineer directed that the two ends of the jumper be installed in a certain sequence using a specific technique.
This technique appeared to cause less binding on the connection at the injector, and the leakage was stopped.
There is no guidance in any vendor manual that states exactly how to install the fuel line jumper (i.e., which side to install first). Only the final torque is specified. The system engineer discussed assembly technique with a vendor representative. The vendor confirmed that it is a good practice to install the fuel line jumpers as the engineer had directed because the lead gaskets on each end of the jumper are easily damaged. The vendor suggested that these specific instructions be added to the model work package to minimize the risk of damage to the gaskets.
This investigation found that the fuel leak was likely caused by gasket damage that occurred during the re-installation of the injectors in October 2011.
PREVIOUS OCCURRENCE EVALUATION No similar failure has been reported by River Bend Station in the last five years.
CORRECTIVE ACTION TO PREVENT RECURRENCE Enhanced work instructions for fuel jumper installation will be added to the vendor manual and to model work orders. This action is being tracked in the station's corrective action program.
SAFETY SIGNIFICANCE
With offsite power available, the high pressure core spray system remained capable of performing its safety function. There were no actual events during this period requiring the Division 3 DG to respond in the emergency mode.
An analysis is being conducted to quantify the risk significance of this event. The results of that analysis will be provided in a supplement to this report.