05000482/LER-2017-001

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LER-2017-001, Condition Prohibited by Technical Specifications Due to One Train of Component Cooling Water Inoperable
Wolf Creek Generating Station
Event date: 03-22-2017
Report date: 05-17-2017
Reporting criterion: 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
4822017001R00 - NRC Website
LER 17-001-00 for Wolf Creek Regarding Condition Prohibited by Technical Specifications Due to One Train of Component Cooling Water Inoperable
ML17143A233
Person / Time
Site: Wolf Creek Wolf Creek Nuclear Operating Corporation icon.png
Issue date: 05/17/2017
From: Smith S L
Wolf Creek
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
WO 17-0047
Download: ML17143A233 (4)


comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to 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.

05000- Wolf Creek Generating Station 482

PLANT CONDITIONS PRIOR TO THE EVENT:

100 % reactor thermal power Mode 1

DESCRIPTION:

On March 22, 2017, with the plant in Mode 1, a work activity isolated the emergency makeup from the Essential Service Water (ESW) [EIIS Code: BI] to the "A" Train Component Cooling Water (CCW) [EIIS Code: CC]. An individual questioned whether the "A" Train CCW was operable in this configuration. Technical Specification (TS) 3.7.7 requires two CCW trains to be operable in Modes 1 through 4. If one train is inoperable, the required action is to restore the CCW train to operable status within

72 hours
8.333333e-4 days
0.02 hours
1.190476e-4 weeks
2.7396e-5 months

or be in Mode 3 in

6 hours
6.944444e-5 days
0.00167 hours
9.920635e-6 weeks
2.283e-6 months

and Mode 5 in

36 hours
4.166667e-4 days
0.01 hours
5.952381e-5 weeks
1.3698e-5 months

. There were no systems, structures or components (SSC) that were inoperable at the start of the event and contributed to the event.

TS Bases 3.7.7 was reviewed and did not state that a CCW train is inoperable if the emergency makeup from ESW is unavailable. Though the TS Bases for CCW does not contain this specific information, it does state that "the associated piping, valves, heat exchanger, and instrumentation and controls required to perform the safety related function are operable.

Updated Safety Analysis Report (USAR) Section 9.2.2, Component Cooling Water, was reviewed and it states that "provisions are included for automatic makeup to the system from the demineralized water storage and transfer system.

USAR Section 9.2.2 also states that "A separate source of emergency makeup is provided from ESW to each train of CCW.

After evaluation by Operations and Engineering, it was concluded that the "A" train CCW was inoperable when emergency makeup from ESW was isolated.

The emergency makeup valve was isolated on March 19, 2017 at 2038 CDT and restored to service on March 23, 2017 at 1811 CDT. This exceeded the allowed outage time of

78 hours
9.027778e-4 days
0.0217 hours
1.289683e-4 weeks
2.9679e-5 months

.

REPORTABILITY:

Technical Specification (TS) 3.7.7, 'Component Cooling Water (CCW) System,' requires two CCW trains to be operable in Modes 1, 2, 3 and 4. The "A" train CCW was inoperable from March 19, 2017 at 2038 CDT and restored to service on March 23, 2017 at 1811 CDT. This exceeded the allowed outage time for one CCW train. This event is reportable in accordance with 10 CFR 50.73(a)(2)(i)(B) as a Condition prohibited by TS.

CAUSE:

It was determined that adequate information was not incorporated into TS Bases 3.7.7, Component Cooling Water (CCW) System, that emergency makeup from ESW is required to maintain a CCW train operable. This is a historical issue.

comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to 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.

05000- Wolf Creek Generating Station 482

CORRECTIVE ACTIONS:

Training Request 2017-0098 was written for the License Requalification program and the Initial License Operator program to present the new guidance for declaring a CCW train inoperable when ESW cannot be aligned for makeup from the Control Room. Essential Reading 2017-013 was issued for licensed personnel.

TS Bases 3.7.7 will be revised to state that if emergency makeup from ESW is unavailable, then the CCW train is inoperable. This action is being tracked by Condition Report (CR) 111808.

SAFETY SIGNIFICANCE

The safety significance of this event is very low. The "B" CCW train was available during the time the "A" train was inoperable. In addition, the "A" train CCW was functional and in operation during the event.

OPERATING EXPERIENCE/PREVIOUS EVENTS

None.