05000334/LER-1917-003, Regarding Reactor Trip Due to Turbine Trip and Automatic Initiation of the Auxiliary Feedwater System
| ML18008A063 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 01/04/2018 |
| From: | Bologna R FirstEnergy Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-17-374 LER 17-003-00 | |
| Download: ML18008A063 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(iv)(B)(1) 10 CFR 50.73(a)(2)(iv)(B)(6) 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)(ix)(A) 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability |
| 3341917003R00 - NRC Website | |
text
FENOC FirstEnergy Nuclear Operating Company Richard D. Bologna Site Vice President January 4, 2018 L-17-374 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Beaver Valley Power Station, Unit No. 1 BV-1 Docket No. 50-334, License No. DPR-66 LER 2017-003-00 10 CFR 50.73 Beaver Valley Power Station P.O. Box 4 Shippingporl, PA 15077 724-682-5234 Fax: 724-643-8069 Enclosed is Licensee Event Report (LER) 2017-003-00, "Beaver Valley Power Station Unit 1 Reactor Trip due to Turbine Trip and Automatic Initiation of Auxiliary Feedwater System". This event is being reported in accordance with 10 CFR 50.73(a)(2)(iv)(A), 10 CFR 50.73(a)(2)(iv)(B)(1), and 10 CFR 50.73(a)(2)(iv)(B)(6).
There are no regulatory commitments contained in this submittal. Any actions discussed in this document that represent intended or planned actions are described for the NRC's information, and are not regulatory commitments.
If there are any questions or if additional information is required, please contact Mr. Brian D. Kremer, Manager, Regulatory Compliance at 724-682-4284.
- p*a~~
Richard D. Bologna Enclosure - Unit 1 LER 2017-003-00 cc:
Mr. D. C. Lew, Acting NRC Region I Administrator Mr. J. A. Krafty, NRC Senior Resident Inspector Ms. S. Haney, Acting NRC Senior Resident Inspector Ms. B. Venkataraman, NRR Project Manager INPO Records Center (via INPO Consolidated Event System)
Mr. L. Winker (BRP/DEP)
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2017) http://www.nrc.govlreading-rmldoc-collectionslnuregslstafflsr1022lr3l) the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Beaver Valley Power Station Unit Number 1 05000 334 1 OF 3
- 4. TITLE Beaver Valley Power Station Unit 1 Reactor Trip due to Turbine Trip and Automatic Initiation of the Auxiliary Feedwater System
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED I
SEQUENTIAL I REV FAC!LllY NAME DOCKET NUMBER MONTH DAY YEAR YEAR MONTH DAY YEAR NUMBER NO.
None 05000 FAC!LllY NAME DOCKET NUMBER 11 07 2017 2017.
003. 00 01 04 2018 None 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
D 20.2201 (b)
D 20.2203(a)(3)(i)
D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A) 1 D 20.2201 (d)
D 20.2203(a)(3)(ii)
D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4)
D 50.13(a)c2)cm)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)c2)ci)
D 50.36(c)(1)(i)(A)
[{] 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
- 10. POWER LEVEL D 20.2203<a>c2><ii)
D 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(v)(A)
D 13.11caH4>
D 20.2203(a>c2>crn>
D 5o.36(c><2>
D 50.73(a)(2)(v)(B)
D 13.11ca><5>
D 20.2203(a)(2)(iv)
D 5o.46(a)(3)(ii>
D 50.73(a)(2)(v)(C)
D 13.77(a>c1>
100 D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 13.11ca><2>
D 20.2203(a)(2)(vi)
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(vii)
D 13.11ca><2>cn)
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D 50.13(a>c2><i)(C)
D OTHER Specify in Abstract below or in Energy Industry Identification System (EIIS) codes identified in the text as [XX].
CONDITIONS PRIOR TO OCCURENCE Beaver Valley Power Station Unit 1 (BV-1) was in Mode 1 at 100% Power There were no Structures, Systems, or Components (SSCs) that were inoperable at the start of the event that contributed to the event.
DESCRIPTION OF EVENT
On November 7, 2017, at 05:04 EST, BV-1 experienced an automatic Reactor Trip due to an automatic Turbine [TRB] Trip initiated by a Main Unit Generator [MG] over-current protection [51] relay [RL Y] actuation. The reactor trip was without complications, with safety related equipment performing their required functions to place and maintain the plant in Mode 3.
All control rods [AA] fully inserted into the reactor core. The Auxiliary Feedwater System [BA] automatically actuated on low Steam Generator [SG] Water Level as expected, and performed as designed. The plant was stabilized in Mode 3 with the normal Main Feedwater System [SJ] in service and the Auxiliary Feedwater System properly secured. Post trip response addressed an issue with both source range detectors [JI] which had no impact on maintaining the plant in Mode 3.
CAUSE OF EVENT
The Direct Technical Cause of this event was conductive foreign material in the isophase bus duct. The foreign material was found during an inspection of the Main Unit Generator lsophase Bus [BU] Duct Cooling System. The foreign material caused an electrical ground fault which led to the generator protection trip and subsequent turbine trip and reactor trip.
High Potential (Hi-Pot) testing was performed on all three phases of the bus, confirming that the "B" phase was faulted.
In 2013, a full bus duct inspection was to be completed but the scope was changed and only a partial bus duct inspection was performed. The Root Cause was determined to be, "individuals made decisions in 2013 that allowed personnel to change the work scope, without following the process to get approval for the change in work scope".
The contributing cause was that the procedure to perform the bus duct inspections was unclear as to what constituted a "full" inspection and if such a "full" inspection was required. The lack of clarity in the procedure created a "weak barrier
and contributed to confusion on the part of the workers.
ANALYSIS OF EVENT
The plant risk associated with the BVPS Unit 1 reactor trip and automatic auxiliary feedwater actuation due to a turbine trip on November 7, 2017 is considered to be very low. This is based on the change in average core damage frequency derived using conditional large early release probability for this event.
This event is being reported pursuant to 10 CFR 50. 73(a)(2)(iv)(A) as a condition that resulted in the automatic actuation of the Reactor Protection System (RPS) and the expected automatic actuation of the Auxiliary Feedwater System.
CORRECTIVE ACTIONS
- 1. The BVPS Unit 1 isophase bus ducts have been properly inspected and cleared of all foreign material. (Complete)
- 2. In order to preclude recurrence, the inspection procedure is being revised to clearly state the requirement to perform a full isophase bus duct inspection.
Completion of item 2 listed above is being tracked in the Corrective Action Program.
PREVIOUS SIMILAR EVENTS
A review of the previous three years identified the following similar event:
BV-1 LER 2014-001-01 "Beaver Valley Unit 1 Trip due to Main Unit Transformer Failure".
CR2017-11134, 11215 Page 3
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