05000255/LER-2013-003, Regarding Both Control Room Ventilation Filtration Trains Declared Inoperable
| ML13288A137 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 10/11/2013 |
| From: | Vitale A Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| PNP 2013-073 LER 13-003-00 | |
| Download: ML13288A137 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 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 |
| 2552013003R00 - NRC Website | |
text
Entergy PNP 2013-073 October 11,2013 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Entergy Nuclear Operations, Inc.
Palisades Nuclear Plant 27780 Blue Star Memorial Highway Covert, Ml 49043 Tel 269 764 2000 Anthony J. Vitale Site Vice President
SUBJECT:
Both Control Room Ventilation Filtration Trains Declared Inoperable Palisades Nuclear Plant Docket 50-255 License No. DPR-20
Dear Sir or Madam:
The enclosed Licensee Event Report (LER) 2013-003-00, Both Control Room Ventilation Filtration Trains Declared Inoperable is submitted in accordance with 10 CFR 50.73.
This letter contains no new commitments and no revisions to existing commitments.
Sincerely,
Attachment:
LER 2013-003, Both Control Room Ventilation Filtration Trains Declared Inoperable CC Administrator, Region Ill, USNRC Project Manager, Palisades, USNRC Resident Inspector, Palisades, USNRC
ATTACHMENT LER 2013-003 BOTH CONTROL ROOM VENTILATION FILTRATION TRAINS DECLARED INOPERABLE 3 Pages Follow
NRC FORM 366 APPROVED BY 0MB NO. 3150-0104 EXPIRES 1013112013 U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
, (tie NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
(See reverse for required number of digits/characters_for each_block)
- 3. PAGE PALISADES NUCLEAR PLANT 05000255 1
OF 3
- 4. TITLE Both Control Room Ventilation Filtration Trains Declared Ino erable
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED SE ENTI L
REV
FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR NUMBER NO MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 08 13 2013 2013 003
- - 00 10 11 2013
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
El 20.2201(b)
U 20.2203(a)(3)O)
U 50.73(a)(2)(i)(C)
U 50.73(a)(2)(vii) 1 U
20.2201(d)
U 20.2203(a)(3)(ii)
U 50.73(a)(2)(ii)(A)
U 50.73(a)(2)(viii)(A)
U 20.2203(a)(1)
U 20.2203(a)(4)
U 50.73(a)(2)(ii)(B)
U 50.73(a)(2)(viii)(B)
U 20.2203(a)(2)(i)
U 50.36(c)(1 )(i)(A)
U 50.73(a)(2)(iii)
U 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL U
20.2203(a)(2)Oi)
U 50.36(c)(1)(ii)(A)
U 50.73(a)(2)(iv)(A)
U 50.73(a)(2)(x)
U 20.2203(a)(2)(iii)
U 50.36(c)(2)
U 50.73(a)(2)(v)(A)
U 73.71(a)(4)
U 20.2203(a)(2)(iv)
U 50.46(a)(3)(ii)
U 50.73(a)(2)(v)(B)
U 73.71(a)(5)
VU U
20.2203(a)(2)(v)
U 50.73(a)(2)(i)(A)
El 50.73(a)(2)(v)(C)
U OTHER Specify Ifl Abstract below or fl U
20.2203(aX2)(vi)
U__50.73(a)(2)(i)(B)
__50.73(a)(2)(v)(D)
NRC_Form_366A
- 12. LICENSEE CONTACT FOR THIS LER FACILITY NAME TELEPHONE NUMBER (Include Area Code)
Otto Gustafson, Licensing Manager (269)_764-2049CAUSE SYSTEM COMPONENT FACTURER REPORTABLE
CAUSE
SYSTEM COMPONENT FACTURER REPORTABLE A
VI AHU A220 Y
- 14. SUPPLEMENTAL REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR SUBMISSION U
YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
NO DATE ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 Single-spaced typewritten lines At 1102 on August 13, 2013, both control room ventilation filtration system trains were declared inoperable in accordance with Technical Specification (TS) 3.7.10, Condition B, due to the inability to fully close control room envelope (CRE) boundary door-15. At 1111 on August 13, 2013, door-15 was closed and TS 3.7.10, Condition B, was exited. TS 3.7.10 allows CRE boundary doors to be opened intermittently, under administrative control for preplanned activities, provided the doors can be rapidly restored to the design condition.
During preplanned maintenance activities, workers attempting to exit the CRE area were unable to open door-i 5 via normal operation of the doors hand wheel. Recent frequent operation of door-i 5 may have caused deformation of a cotter pin within the doors normal operating mechanism. Deformation of the cotter pin could cause the normal operation of door-i 5 to function intermittently. To allow exiting, workers opened door-15 using the emergency egress latch that activated an alarm condition on the door. During exiting, inadvertent operation of the doors hand wheel in the closed direction caused the doors latching pins to extend out causing interference between the door and the door frame preventing door-i 5 from fully closing.
Due to the door being in an alarmed condition, the doors latching pins were unable to be immediately retracted. After approximately nine minutes, the doors latching pins were retracted by use of the emergency egress latch and the door was restored to the design condition, i.e., closed.
The cotter pin was replaced. Future potential corrective actions include increased preventative maintenance frequency to replace the cotter pin and restricting the use of the emergency egress latch.
NRC FORM 366 (10-2010)U.S. NUCLEAR REGULATORY COMMISSION (1O2O1O)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE SEQUENTIAL REVISION YEAR NUMBER NUMBER PALISADES NUCLEAR PLANT 05000255 2013 003 00 2
OF 3
SYSTEM DESIGN/FUNCTION The control room ventilation [AHU] filtration system [VI] safety function is to limit radiation exposure of control room personnel during any of the postulated design basis events within the guidelines of 10 CFR 50, Appendix A and General Design Criterion 19. Specifically, control room ventilation filtration is designed to maintain a habitable environment in the control room for 30 days of occupancy after a design basis accident without exceeding a five rem total effective dose equivalent.
EVENT DESCRIPTION
In Mode I at 100% power, at 1102 on August 13, 2013, both control room ventilation filtration system trains were declared inoperable in accordance with Technical Specification (TS) 3.7.10, Condition B, due to the inability to fully close control room envelope (ORE) boundary door-15. At 1111 on August 13, 2013, door-15 was closed and TS 3.7.10, Condition B, was exited. TS 3.7.10 allows ORE boundary doors to be opened intermittently, under administrative control for preplanned activities, provided the doors can be rapidly restored to the design condition.
At the time of the event, left (A) train of the control room ventilation filtration was inoperable for preplanned maintenance. No additional structures, components, or systems were inoperable and contributed to the event at the time of discovery.
The event was initially reported to the NRC in accordance with 10 CFR 50.72(b)(3)(v)(D) as documented in event report #49276. This LER is submitted based on NUREG 1022 revision 3, section 3.2.7 guidance which identifies that the requirements of 10 CFR 50.73(a)(2)(v)(D) apply when a system that is used to mitigate the consequences of an accident was declared TS inoperable and no redundant system or equipment could be declared operable. Based on the limited amount of air in-leakage into the ORE with door-I 5 only slightly open for nine minutes, the subsequent engineering evaluation determined the right (B) train of the control room ventilation filtration system would have maintained the ability to limit control room operator doses below required limits and no loss of safety function occurred.
CAUSE OF THE EVENT
During preplanned maintenance activities, workers attempting to exit the ORE area were unable to open door-15 via normal operation of the doors hand wheel. Recent frequent operation of door-15 may have caused deformation of a cotter pin within the doors normal operating mechanism.
Deformation of the cotter pin could cause the normal operation of door-i 5 to function intermittently. To allow exiting, workers opened door-iS using the emergency egress latch that activated an alarm condition on the door. During exiting, inadvertent operation of the doors hand wheel in the closed direction caused the doors latching pins to extend out causing interference between the door and the door frame preventing door-I 5 from fully closing. Due to the door being in an alarmed condition, the doors latching pins were unable to be immediately retracted. After approximately nine minutes, the doors latching pins were retracted by use of the emergency egress latch and the door was restored to the design condition, i.e., closed.U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE SEQUENTIAL REVISION YEAR NUMBER NUMBER PALISADES NUCLEAR PLANT 05000255 2013 003 00 3
OF 3
ASSESSMENT OF SAFETY CONSEQUENCES
The temporary loss of ability to fully close door-I 5 did not challenge nuclear or radiological safety.
No actual loss of safety function occurred. The control room ventilation filtration system maintained the ability to limit control room operator doses below required limits.
CORRECTIVE ACTIONS TAKEN The cotter pin within the doors normal operating mechanism was replaced.
CORRECTIVE ACTIONS TO BE TAKEN Potential corrective actions include increased frequency of preventative maintenance to replace the cotter pin and restricting the use of the emergency egress latch. Additionally, to limit wear on door components during periods of expected frequent operation, the implementation of administrative controls that would maintain the door in the open position with dedicated personnel stationed at the door to immediately close the door when required.
PREVIOUS SIMILAR EVENTS
Palisades has experienced operating issues with door-I 5 on previous occasions; however the previous events did not require submittal of a LER under the guidance of NUREG 1022, revision 2.