05000286/LER-2013-006, Regarding Technical Specification Prohibited Condition Due to an Inoperable 33 Station Battery Caused by a Cell Crack
| ML13346A015 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 12/05/2013 |
| From: | Ventosa J Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-13-150 LER 13-006-00 | |
| Download: ML13346A015 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 2862013006R00 - NRC Website | |
text
VEntergy Indian Point Energy Center 450 Broadway, GSB P.O. Box 249 Buchanan, N.Y. 10511-0249 Tel (914) 254-6700 John A. Ventosa Site Vice President Administration NL-13-150 December 5, 2013 U.S. Nuclear Regulatory Commission Document Control Desk 11545 Rockville Pike, TWFN-2 F1 Rockville, MD 20852-2738
SUBJECT:
Licensee Event Report # 2013-006-00, "Technical Specification Prohibited Condition Due to an Inoperable 33 Station Battery Caused by a Cell Crack" Indian Point Unit No. 3 Docket No. 50-286 DPR-64
Dear Sir or Madam:
Pursuant to 10 CFR 50.73(a)(1), Entergy Nuclear Operations Inc. (ENO) hereby provides Licensee Event Report (LER) 2013-006-00. The attached LER identifies an event where there was a Technical Specification prohibited condition for an inoperable station battery 33, which is reportable under 10 CFR 50.73(a)(2)(i)(B). This condition was recorded in the Entergy Corrective Action Program as Condition Report CR-IP3-2013-04216.
There are no new commitments identified in this letter. Should you have any questions regarding this submittal, please contact Mr. Robert Walpole, Manager, Licensing at (914) 254-6710.
Sincerely, JAV/cbr cc:
Mr. William Dean, Regional Administrator, NRC Region I NRC Resident Inspector's Office, Indian Point 3 Ms. Bridget Frymire, New York State Public Service Commission LEREvents@lNPO.org (uL
Abstract
On October 9, 2013, during performance of weekly surveillance test 3-PT-W013 (Station Battery Visual Inspection) on station battery 33, a crack was discovered in the battery jar of cell 14 which extended below the high level fluid line.
The 33 battery is required to be operable per Technical specification 3.8.4 (DC Sources - Operating) in Modes 1-4.
The 33 battery was declared inoperable after its ability to perform its design function in a seismic event was questioned due to possible crack propagation.
An emergency temporary modification was installed on October 9, 2013, restoring operability.
On October 17, 2013, cell 14 on the 33 battery was replaced.
The direct cause of the crack in cell 14 was corrosion of the positive battery post seal area which caused the post to expand creating excessive strain on the lid of the battery jar.
The most probable cause was chemically induced degradation which weakened the jar wall allowing the stress being transferred from the cover crack to physically separate the jar.
An immediate corrective action was to prepare an emergency temporary modification and install the modification to restore the battery operable.
Corrective actions
included replacing cell 14 of the 33 battery.
A failure analysis is being performed by an independent vendor.
The event had no significant effect on public health and safety.
(if more space is required, use additional copies of (if more space is required, use additional copies of NRC Form 366A) (17)
Corrective Actions
The following corrective actions have been or will be performed under Entergy's Corrective Action Program to address the cause and prevent recurrence:
- A new battery cell was installed to replace the existing battery 33 cell 14.
" A failure analysis is being performed by an independent vendor.
Event Analysis
The event is reportable under 10CFR50.73(a) (2) (i) (B).
The licensee shall report any operation or condition which was prohibited by the plants TS.
This condition meets the reporting criteria because the 33 battery was discovered with a cracked cell that rendered the battery inoperable due to the inability to meet its seismic qualification.
The last time the battery was checked was on the previous weekly surveillance.
The likely time the battery cell was inoperable was greater than the TS allowed completion time of two hours.
Therefore, the battery cell cracked condition is a TS prohibited condition.
Past Similar Events A review was performed of the past three years of Licensee Event Reports (LERs) for events reporting a TS violation due to inoperable battery.
No LERs were identified.
Safety Significance
This event had no significant effect on the health and safety of the public. There were no actual safety consequences for the event because there were no accidents or events during the degraded condition.
The 33 battery was declared inoperable due to the potential inability to meet its seismic qualification but it was available at all times to support the associated DC loads.
An emergency temporary modification was installed to restore the battery cell to an operable condition.
There were no significant potential safety consequences of this event.
The DC electrical power system is designed so that the loss of any train of DC electrical power subsystem does not prevent the minimum safety function from being performed.
One battery charger is available to each battery so that the four batteries will always be at full charge in anticipation of a loss of AC power incident.
With one battery inoperable, the remaining batteries, battery chargers and EDS were operable and available to perform their safety function.
In addition, battery charger 35 is an installed spare that can be used as the associated charger for any of the batteries.
Also, failure to supply power to the vital instrument bus would cause the associated Static Inverter automatic static transfer switch to transfer to its alternate source of power.
A loss of offsite power could result is stripping the power supply following a safety injection signal but they would be re-energized in accordance with plant procedures.