05000382/LER-2019-002, (Waterford 3), Control Room Envelope Declared Inoperable Due to Outside Air Intake Isolation Valve Exceeding Closed Stroke Time During Inservice Testing Resulting in Event or Condition
| ML19049A028 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 02/18/2019 |
| From: | Signorelli J Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| W3F1-2019-0019 LER 2019-002-00 | |
| Download: ML19049A028 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 3822019002R00 - NRC Website | |
text
Entergy Operations, Inc.
17265 River Road Killona, LA 70057-3093 Tel 504-739-6032 John V. Signorelli Manager, Regulatory Assurance (Acting) 10 CFR 50.73 W3F1-2019-0019 February 18, 2019 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 The attached report is being sent pursuant to 10 CFR 50.73.
There are no regulatory commitments contained in this correspondence.
If you have any questions or require additional information, please contact the Acting Regulatory Assurance Manager, John V. Signorelli, at (504) 739-6032.
Respectfully, John V. Signorelli JVS/rd cc:
NRC Region IV Regional Administrator NRC Senior Resident Inspector - Waterford Steam Electric Station, Unit 3 NRR Project Manager
Subject:
Licensee Event Report (LER) 2019-002-00 Control Room Envelope Declared Inoperable due to Outside Air Intake Isolation Valve Exceeding Closed Stroke Time During Inservice Testing Resulting in Event or Condition that Could Have Prevented Fulfillment of a Safety Function Waterford Steam Electric Station, Unit 3 (Waterford 3)
NRC Docket No. 50-382 Renewed Facility Operating License No. NPF-38
Enclosure:
Waterford 3 Licensee Event Report 2019-002-00
ENCLOSURE W3F1-2019-0019 Entergy Operations, Inc.
Waterford 3 Licensee Event Report 2019-002-00
NRC FORM 366 (04-2018)
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (04-2018)
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/nuregs/staff/sr1022/r3/)
APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. Facility Name Waterford Steam Electric Station, Unit 3
- 2. Docket Number 05000382
- 3. Page 1 OF 3
- 4. Title Control Room Envelope Declared Inoperable due to Outside Air Intake Isolation Valve Exceeding Closed Stroke Time During Inservice Testing Resulting in Event or Condition that Could Have Prevented Fulfillment of a Safety Function
- 5. Event Date
- 6. LER Number
- 7. Report Date
- 8. Other Facilities Involved MONTH DAY YEAR YEAR SEQUENTIAL NUMBER REV NO.
MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 12 19 2018 2019 -
002
- - 00 02 18 2019 FACILITY NAME DOCKET NUMBER
- 9. Operating Mode
)
No Abstract (Limit to 1400 spaces, i.e., approximately 14 single-spaced typewritten lines)
On December 19, 2018, at 2322 Central Standard Time (CST), the shift operating crew declared the Control Room Envelope inoperable in accordance with Technical Specification (TS) 3.7.6.1 due to valve HVC-102 exceeding its maximum allowed closed stroke time of 2.0 seconds during performance of inservice testing.
The actual closed stroke time was 2.1 seconds. Valve HVC-102 is part of the Control Room Envelope. The inoperability of the Control Room Envelope resulted in an event or condition that could have prevented fulfillment of a safety function. The TS required action to implement mitigating actions was completed on December 19, 2018 at 2355 CST by placing the control room ventilation system in isolate mode.
An equipment failure evaluation determined that the cause of this event was that there was lack of lubrication in the HVC-102 valve actuator. Actions were taken to rebuild and properly lubricate the valve actuator.
Following a successful inservice test of HVC-102, the Control Room Envelope was declared operable on December 27, 2018. Additional corrective action includes reviewing the maintenance procedure and vendor manual to determine if a change in the preventive maintenance task is warranted.
EVENT DESCRIPTION
A. Plant Status At the time of this event, Waterford 3 was in Mode 1 100% reactor power. There were no other structures, systems or components out of service that contributed to this event.
B. Event Chronology On December 19, 2018, during scheduled inservice testing in accordance with surveillance procedure OP-903-119, "Secondary Auxiliaries Quarterly IST [Inservice Testing] Valve Tests," valve HVC-102 [ISV] exceeded its maximum allowed closed stroke time of 2.0 seconds. Actual closed stroke time was 2.1 seconds. HVC-102 is the Control Room Normal Outside Air Intake Upstream Isolation Valve and is part of the Control Room Envelope [VI]. At 2322 CST, the shift operating crew declared the Control Room Envelope inoperable in accordance with Technical Specification (TS) 3.7.6.1, "Control Room Emergency Air Filtration System." TS 3.7.6.1 requires that two control room emergency air filtration trains [VI] shall be OPERABLE. Operations entered TS 3.7.6.1 action b, which requires that with one or more control room emergency air filtration trains inoperable due to inoperable Control Room Envelope boundary in MODES 1, 2, 3, or 4, then: 1. Immediately initiate action to implement mitigating actions; 2. Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, verify mitigating actions ensure Control Room Envelope occupant exposures to radiological, chemical, and smoke hazards will not exceed limits; and 3. Within 90 days, restore the Control Room Envelope boundary to OPERABLE status.
Actions b.1 and b.2 were completed by placing the control room ventilation system in isolate mode on December 19, 2018 at 2355 CST.
This event is reportable pursuant to 10 CFR 50.73(a)(2)(v)(D), "Any event or condition that could have prevented fulfillment of a safety function of structures or systems that are needed to:
(D) mitigate the consequences of an accident," due to the Control Room Envelope being inoperable.
C. Event Causes An equipment failure evaluation determined that the cause of this event is that there was lack of lubrication in the HVC-102 valve operator.
CORRECTIVE ACTIONS
(1) Rebuild and properly lubricate the valve actuator (complete).
(2) Review the maintenance procedure and vendor manual to determine if a change in the preventive maintenance task is warranted (planned). Page 3
of 3 COMMISSION (04-2018)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc/gov/reading-rm/doc-collections/nuregs/staff/sr1022/r3/)
APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. LER NUMBER Waterford Steam Electric Station, Unit 3 05000382 YEAR SEQUENTIAL NUMBER REV NO.
2019 002 00 SAFETY EVALUATION HVC-102 is the Control Room Normal Outside Air Intake Upstream Isolation Valve. The valve automatically opens when either control room air handling unit is started. This valve fails closed and automatically closes upon a Safety Injection Actuation Signal, High Toxic Chemical Signal, High Radiation Signal, or when both control room air handling unit fans are not running. This valve is analyzed to close in 2 seconds or less in the safety analyses evaluating the control room boundary for a High Radiation Signal or Toxic Chemical Signal. The Inservice Testing Program tests the HVC-102 valve to show that the valve can meet the closure time limit of 2 seconds.
An analysis was performed of the impact of the increase of 0.1 seconds to the HVC-102 closure time. For this analysis, the design basis calculations supporting the safety basis for HVC-102 were reviewed. In addition, a search for other calculations or documents was performed to ensure that there are no other impacts due to the increased closure time. This search did not identify any impacts other than the design basis calculations. This analysis determined that with the increase of 0.1 seconds, the valve could still perform its safety function of maintaining control room habitability by closing to isolate normal control room ventilation. This is due to the fact that there is sufficient margin available in the design basis calculations.
Based on the above, although the Control Room Envelope was declared inoperable per TS 3.7.6.1, engineering analysis later determined that the system was capable of performing its safety function.
Due to this, there were no actual consequences to general safety of the public, nuclear safety, industrial safety or radiological safety for these events.
PREVIOUS OCCURRENCES
A review of the Waterford 3 corrective action program and previous Licensee Event Reports for the previous 3 years revealed no similar events as described in NUREG-1022 guidance.
Energy Industry Identification System (EIIS) codes and component codes are identified in the text as [XX].