05000390/LER-2015-005, Regarding Failure to Enter Technical Specification 3.6.12, Ice Condenser Doors, Condition B and Perform Required Actions
| ML15320A298 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 11/16/2015 |
| From: | Walsh K Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 15-005-00 | |
| Download: ML15320A298 (7) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 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 |
| LER closed by | |
| IR 05000390/2000391 (12 February 2016) | |
| 3902015005R00 - NRC Website | |
text
m Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381 November 16, 2015 10CFR 50.73 ATTN:
Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 1 Facility Operating License No. NPF-90 NRC Docket No. 50-390 Subject; Licensee Event Report 390/2015-005-00, Failure to Enter Technical Specification 3.6.12, Ice Condenser Doors, Condition B and Perform Required Actions This submittal provides Licensee Event Report (LER) 390/2015-005-00. This LER provides details concerning failure to follow the required actions of Technical Specification 3.6.12 Condition B. This report is being submitted in accordance with 10CFR 50.73(a)(2)(i)(B).
Please direct any questions concerning this matter to Gordon Arent, WBN Licensing Director, at (423) 365-2004.
Respectfully, Kevin T. Walsh Site Vice President Watts Bar Nuclear Plant Enclosure cc: See Page 2
U.S. Nuclear Regulatory Commission Page 2 November 16, 2015 cc (Enclosure):
NRC Regional Administrator - Region II NRC Senior Resident Inspector - Watts Bar Nuclear Plant, Unit 1 NRC Project Manager - Watts Bar Nuclear Plant, Unit 1
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (02-2014) iM) LICENSEE EVENT REPORT (LER)
(See Page 2 for required number of digits/characters for each block)
APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 01/31/2017 Estimated burden per response to confiply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.
Reported lessons learned are incorporated intothe licensing prxess and fed back to industry.
Send comments regarding burden estimate to the FOIA, Privacy and Infomiation Collections Branch (T-5 F53). U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to lnfocollects.Resource@nrc.gov, andtothe DeskOfficer, Office ofInformation and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. Ifa meansusedto impose an information collection doesnotdisplay a currently valid 0MB control number, the NRC maynotconductor sponsor,and a personis notrequired to respondto, the information collection.
- 1. FACILITY NAME Watts Bar Nuclear Plant, Unit 1
- 2. DOCKET NUMBER 05000390
- 3. PAGE 1
OF 5
- 4. TITLE Failure to Enter Technical Specification 3.6.12, Ice Condenser Doors, Condition B and Perform Required Actions
- 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 N/A DOCKET NUMBER N/A 09 16 2015 2015 005 00 11 16 2015 FACILITY NAME N/A DOCKET NUMBER N/A
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTEDPURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 1 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii) 20.2201(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 91 20.2203(a)(2)(ii) 50.36(0(1 )(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C)
OTHER 20.2203(a)(2)(vi)
^
50.73(a)(2)(i)(B) 50.73(a)(2)(v)(D)
Specify in Abstract below or in
I.
PLANT OPERATING CONDITIONS BEFORE THE EVENT
Watts Bar Nuclear Plant (WBN) Unit 1 was in Mode 1 at 91 percent rated thermal power (RTP).
II.
DESCRIPTION OF EVENT
A.
Event On September 16, 2015, at 0536 Eastern Daylight Time (EDT), WBN Unit 1 operations personnel received a report from maintenance personnel that a scaffold was found blocking four (4) intermediate deck doors {EIIS;DR} in the upper plenum of the WBN Unit 1 ice condenser {EIIS:BC}.
Based on this report. Technical Specification (TS) Limiting Condition for Operation (LCO) 3.6.12 Condition B was entered, requiring that the maximum ice bed temperature is verified to be less than 27 degrees F once per four hours (Action B.I) and to restore the doors to OPERABLE status in 14 days (Action B.2).
Based on a review of maintenance records, maintenance was authorized to build the scaffold on September 8, 2015. Assuming itwas built the same day, the fourteen day completion time of TS 3.6.12 Action B.2 was not exceeded. A review of ice bed temperatures between September 8, 2015 and the time the scaffold was removed (September 17, 2015) show that ice bed temperatures never exceeded 27 degrees F as required by TS 3.6.12 Action B.I.
This event is reportable under 10 CFR 50.73(a)(2)(i)(B), "Operation or Condition Prohibited by Technical Specifications."
B.
Inoperable Structures, Components, or Systems that Contributed to the Event No inoperable structures, components, or systems contributed to this event.
C.
Dates and Approximate Times of Occurrences
Date Time Event 09/08/15 N/A 09/16/15 0536 EDT Operations authorizes maintenance to build scaffolding in the ice condenser. It is assumed the scaffold is installed the same day.
WBN Operations personnel receive a report that four intermediate deck doors are inoperable due to a scaffold preventing their opening.
Personnel commence completion of Actions B.I and B.2 as required by TS 3.6.12.
09/17/15 Scaffolding is removed from the Unit 1 ice condenser.
D.
Manufacturer and Model Number of Components that Failed There were no failed components associated with this event.
E.
Other Systems or Secondary Functions Affected
There were no systems or secondary functions affected by this event.
F.
Method of discovery of each Component or System Failure or Procedural Error
The failure to properly enter the Technical Specification action statement for inoperable intermediate deck doors was identified by maintenance personnel while performing inspections of the ice condenser.
G.
Failure Mode and Effect of Each Failed Component There were no component failures associated with this event.
H.
Operator Actions
Upon being informed of the inoperable intermediate deck doors, operations personnel commenced completion of Actions B.1 and B.2 as required by TS 3.6.12.
I.
Automatically and Manually Initiated Safety System Responses
There were no automatic or manual system responses associated with this event.
III.
CAUSE OF THE EVENT
A. The cause of each component or system failure or personnel error, ifknown.
There were no component or system failures as a result of this event notification.
B.
The cause(s) and circumstances for each human performance related root cause.
The cause of the event was a failure by the Senior Reactor Operator (SRO) to validate and understand the exact location of the scaffold build when he signed the associated Work Order (WO) attachment stating that the scaffold would not affect operation of or access to plant equipment.
IV.
ANALYSIS OF THE EVENT
Ice condenser maintenance is a significant task performed every refueling outage at ice condenser plants.
Where allowed, certain maintenance activities are performed while the unit is still at power. Analysis of the ice condenser shows that blocking five intermediate deck doors in a single ice bay will not prevent the ice condenser from performing its safety function. This scaffolding had been installed less than 14 days prior to the unit being shutdown. For this event, the issue was failure to enter LCO 3.6.12 Condition B and perform 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> temperature monitoring. Subsequent review of ice condenser temperatures showed the temperatures never approached the 27 degrees F limitation specified by TS 3.6.12 Action B.1.
Accordingly, there was no actual or potential safety consequences from this event.
V.
ASSESSMENT OF SAFETY CONSEQUENCES
A. Availability of systems or components that could have performed the same function as the components and systems that failed during the event The loss of four intermediate deck doors would not have prevented the ice condenser from performing its safety function in the event of an accident.
B.
For events that occurred when the reactor was shut down, availability of systems or components needed to shutdown the reactor and maintain safe shutdown conditions, remove residual heat, control the release of radioactive material, or mitigate the consequences of an accident Not applicable.
C.
For failure that rendered a train of a safety system inoperable, an estimate of the elapsed time from the discovery of the failure until the train was returned to service Not applicable.
VI.
CORRECTIVE ACTIONS
This event was entered into the Tennessee Valley Authority (TVA) Corrective Action Program (CAP) and is being tracked under condition report (CR) 1082469.
A.
Immediate Corrective Actions
Upon identifying the inoperable intermediate deck doors caused by installed scaffolding, the required actions of Technical Specification 3.6.12 Condition B were performed and the scaffolding was promptly removed.
B.
Corrective Actions to Prevent Recurrence The SRO Involved with this event was coached regarding his responsibility to positively validate the location of the scaffold. The findings of this event were communicated to Operations Department personnel.
VII.
ADDITIONAL INFORMATION
A.
Previous similar events at the same plant No events were identified within the past three years associated with a failure by operations personnel to recognize the need to enter a Technical Specification LCO.
B.
Additional Information
None.
C.
Safety System Functional Failure Consideration This condition did not result in a safety system functional failure.
D. Scrams with Complications Consideration There was no scram associated with this report.
VIII.
COMMITMENTS
None.
I.
PLANT OPERATING CONDITIONS BEFORE THE EVENT
Watts Bar Nuclear Plant (WBN) Unit 1 was in Mode 1 at 91 percent rated thermal power (RTP).
II.
DESCRIPTION OF EVENT
A.
Event On September 16, 2015, at 0536 Eastern Daylight Time (EDT), WBN Unit 1 operations personnel received a report from maintenance personnel that a scaffold was found blocking four (4) intermediate deck doors {EIIS;DR} in the upper plenum of the WBN Unit 1 ice condenser {EIIS:BC}.
Based on this report. Technical Specification (TS) Limiting Condition for Operation (LCO) 3.6.12 Condition B was entered, requiring that the maximum ice bed temperature is verified to be less than 27 degrees F once per four hours (Action B.I) and to restore the doors to OPERABLE status in 14 days (Action B.2).
Based on a review of maintenance records, maintenance was authorized to build the scaffold on September 8, 2015. Assuming itwas built the same day, the fourteen day completion time of TS 3.6.12 Action B.2 was not exceeded. A review of ice bed temperatures between September 8, 2015 and the time the scaffold was removed (September 17, 2015) show that ice bed temperatures never exceeded 27 degrees F as required by TS 3.6.12 Action B.I.
This event is reportable under 10 CFR 50.73(a)(2)(i)(B), "Operation or Condition Prohibited by Technical Specifications."
B.
Inoperable Structures, Components, or Systems that Contributed to the Event No inoperable structures, components, or systems contributed to this event.
C.
Dates and Approximate Times of Occurrences
Date Time Event 09/08/15 N/A 09/16/15 0536 EDT Operations authorizes maintenance to build scaffolding in the ice condenser. It is assumed the scaffold is installed the same day.
WBN Operations personnel receive a report that four intermediate deck doors are inoperable due to a scaffold preventing their opening.
Personnel commence completion of Actions B.I and B.2 as required by TS 3.6.12.
09/17/15 Scaffolding is removed from the Unit 1 ice condenser.
D.
Manufacturer and Model Number of Components that Failed There were no failed components associated with this event.
E.
Other Systems or Secondary Functions Affected
There were no systems or secondary functions affected by this event.
F.
Method of discovery of each Component or System Failure or Procedural Error
The failure to properly enter the Technical Specification action statement for inoperable intermediate deck doors was identified by maintenance personnel while performing inspections of the ice condenser.
G.
Failure Mode and Effect of Each Failed Component There were no component failures associated with this event.
H.
Operator Actions
Upon being informed of the inoperable intermediate deck doors, operations personnel commenced completion of Actions B.1 and B.2 as required by TS 3.6.12.
I.
Automatically and Manually Initiated Safety System Responses
There were no automatic or manual system responses associated with this event.
III.
CAUSE OF THE EVENT
A. The cause of each component or system failure or personnel error, ifknown.
There were no component or system failures as a result of this event notification.
B.
The cause(s) and circumstances for each human performance related root cause.
The cause of the event was a failure by the Senior Reactor Operator (SRO) to validate and understand the exact location of the scaffold build when he signed the associated Work Order (WO) attachment stating that the scaffold would not affect operation of or access to plant equipment.
IV.
ANALYSIS OF THE EVENT
Ice condenser maintenance is a significant task performed every refueling outage at ice condenser plants.
Where allowed, certain maintenance activities are performed while the unit is still at power. Analysis of the ice condenser shows that blocking five intermediate deck doors in a single ice bay will not prevent the ice condenser from performing its safety function. This scaffolding had been installed less than 14 days prior to the unit being shutdown. For this event, the issue was failure to enter LCO 3.6.12 Condition B and perform 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> temperature monitoring. Subsequent review of ice condenser temperatures showed the temperatures never approached the 27 degrees F limitation specified by TS 3.6.12 Action B.1.
Accordingly, there was no actual or potential safety consequences from this event.
V.
ASSESSMENT OF SAFETY CONSEQUENCES
A. Availability of systems or components that could have performed the same function as the components and systems that failed during the event The loss of four intermediate deck doors would not have prevented the ice condenser from performing its safety function in the event of an accident.
B.
For events that occurred when the reactor was shut down, availability of systems or components needed to shutdown the reactor and maintain safe shutdown conditions, remove residual heat, control the release of radioactive material, or mitigate the consequences of an accident Not applicable.
C.
For failure that rendered a train of a safety system inoperable, an estimate of the elapsed time from the discovery of the failure until the train was returned to service Not applicable.
VI.
CORRECTIVE ACTIONS
This event was entered into the Tennessee Valley Authority (TVA) Corrective Action Program (CAP) and is being tracked under condition report (CR) 1082469.
A.
Immediate Corrective Actions
Upon identifying the inoperable intermediate deck doors caused by installed scaffolding, the required actions of Technical Specification 3.6.12 Condition B were performed and the scaffolding was promptly removed.
B.
Corrective Actions to Prevent Recurrence The SRO Involved with this event was coached regarding his responsibility to positively validate the location of the scaffold. The findings of this event were communicated to Operations Department personnel.
VII.
ADDITIONAL INFORMATION
A.
Previous similar events at the same plant No events were identified within the past three years associated with a failure by operations personnel to recognize the need to enter a Technical Specification LCO.
B.
Additional Information
None.
C.
Safety System Functional Failure Consideration This condition did not result in a safety system functional failure.
D. Scrams with Complications Consideration There was no scram associated with this report.
VIII.
COMMITMENTS
None.6. LER NUMBER SEQUENTIAL NUMBER 005 REV NO.
00
- 3. PAGE OF