05000391/LER-2018-004, Failure to Implement Annunciator Response Process Results in a Condition Prohibited by Technical Specifications

Failure to Implement Annunciator Response Process Results in a Condition Prohibited by Technical Specifications

ML18264A192
Person / Time
Site:	Watts Bar
Issue date:	09/21/2018
From:	Simmons P Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 2018-004-00
Download: ML18264A192 (8)

LER-2018-004, Failure to Implement Annunciator Response Process Results in a Condition Prohibited by Technical Specifications

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(ix)(A)
3912018004R00 - NRC Website

text

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 37381 September 21,2018 10 cFR 50.73 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 Facility Operating License No. NPF-96 NRC Docket No. 50-391 Subject: Licensee Event Report 391/2018-004-00, Failure to lmplement Annunciator Response Process Results in a Condition Prohibited by Technical Specifications This submittal provides Licensee Event Report (LER) 391/2018-004-00. This LER provides details concerning a failure by operations personnelto recognize an equipment alarm, resulting in a condition prohibited by Technical Specifications. This condition is being reported in accordance with 10 CFR 50.73(a)(2)(iXB) as an operation or condition prohibited by Technical Specifications.

There are no new regulatory commitments contained in this letter. Please direct any questions concerning this matter to Kim Hulvey, WBN Licensing Manager, at (423) 365-7720.

Site Vice President Watts Bar Nuclear Plant Enclosure cc: see Page 2 Respectfully,

U.S. Nuclear Regulatory Commission Page 2 September 21,2}fi cc (Enclosure):

NRC Regiona! Administrator - Region ll NRC Senior Resident Inspector - Watts Bar Nuclear Plant

NRC FORM 366 (04-2018)

U.S. NUCLEAR REGULATORY COMMISSION LIGENSEE EVENT REPORT (LER)

APPROVED BY OMB: NO. 3150-0104 EXPIRES:0313112020 Estimatsd burden per response h comply witr tris mandatory collection request 80 houns.

Reporbd hssons learned ae inoorporabd inb the licensing process and fed back b industy. Send oornnnenb regarding burden estimab b he lnftrmdion Servioes Branch [f-2 F43), U.S. Nuclear Regulabry Commission, Washingbn, DC 2055S0001,0r by +mdl b lnfooollec,ts. Resourue@nrc.gov, and b fie Desk Officer, Ofrce of lnftrmation and Regulatory Affairs, NEO&10202, (315efi04), 0ffice of Management and Budget Washingbn, DC 20503. lf a means used h impose an information oollecton does not display a cunenty vdid OMB mnfol number, he NRC may not conduct o sponsor, and a person is not required h respond b, the information collection.

1. Facility Name Watts Bar Nuclear Plant, Unit 2

2. Docket Number 0s000391

3. Page 1

OF 6

4. Title Failure to lmplement Annunciator Response Process Results in a Condition Prohibited by Technical Specifications

5. Event Date

6. LER Number

7. Report Date

8. Other Facilities lnvolved Monthl Day I Year year I S"Ouential I

Number Rev No.

Month I Day Year Facility Name NA Docket Number 05000 07 27 I 2018 2019 f004

- 00 09 121 2018 Facility Name NA Docket Number 05000

9. Operating Mode

11. This Report is Submitted Pursuant to the Requirements of 10 CFR S: (G[eck all l/f,at apply) 1 tr 20.2201(b) tr zo.zzos(a)(3)(i) n 50.73(aX2XiiXA) tl s0.73(aX2XviiiXA) tr zo.2zo1(d) tr 2o.zzas(aX3Xii) tr s0.73(aX2XiiXB) tr 80.73(aX2XviiiXB) tr zo.zzos(aXl) tr zo.22os(aX4) tr s0.73(ax2xiii) tl 50.73(a)(2)(ix)(A) tl zo.2zas(aX2Xi) tr s0.36(c)(1XiXA) tr s0.73(aX2XivXA) tr 50.73(aX2Xx)

10. Power Level tl zo.zzas(aX2Xii) tr 50.36(c)(1)(iiXA) n s0.73(aX2XvXA) tr rc.r1(a)(4) 100 tr 2o.2zo3(aX2)(iii) tl s0.36(cX2) tr 50.73(aX2XvXB) tr n.r1(aXs) tr zo.zzos(aX2Xiv) tl s0.46(ax3xii) tl s0.73(aX2XvXc) tr rc.rr(a)(l) tr 2o.22os(aX2Xv) n s0.73(ax2xixA) tr 50.73(aX2Xv)(D) n fi.rr(ax2xi) tr zo.22os(aX2Xvi)

X b0.73(aX2XiXB) tl s0.73(aX2Xvii) tr B.rr(aX2X.i) tl s0.73(ax2xixc) t] OTHER Specify in Abstract below or in

B. Status of structures, components, or systems that were inoperable at the start of the event and that contributed to the event

Train A, Containment Purge Air Exhaust RM (2-RM-90-130) was inoperable at 1007 on July 26, 2018, but was not recognized until 1040 on July 27,2018.

Train B, Containment Purge Air Exhaust RM (2-RM-90-131), remained operable to continuously monitor the radioactivity in the exhaust air from the containment atmosphere.

C. Dates and approximate times of occunences Date Time (EDr) 07126118 1007 lnstrument malfunction ANN 193-D alarmed in MCR.

2-RM-90-1 30 inoperable.

07127118 1040 While preparing to place Unit 2 Purge in service, notification was received 2-RM-90-130 would not source check, and the green "operate" light was not illuminated. At this time, it was also noted that instrument malfunction ANN 193-D was illuminated.

Unit 2 entered TS LCO 3.3.6 Condition B, and TS LCO 3.6.3 Condition A.

07127118 1158 A review of plant data revealed that the instrument malfunction ANN 193-D alarmed in the MCR at 1007 on July 26,2018.

Annunciator Verifi cation procedure, 2-PI-OPS-ANN, was initiated to account for all annunciators.

07127118 1251 To comply with TS LCO 3.6.3, Condition A, a dedicated operator was assigned to close lower compartment purge valves 2-FCV-30-37 and ?-FCV-30-40 in the event of a CVI signal.

08102118 2300 2-RM-90-130 returned to service. Unit 2 exited TS LCO 3.3.6 Conditions A and B, and TS LCO 3.6.3 Condition A.

D. Manufacturer and model number of each component that failed during the event

The malfunction of 2-RM-90-130 was due to a failed high voltage power supply

{EllS: JX} associated with the instrument's ratemeter. GeneralAtomics part number 02810443-001 was replaced.

Event

E. Other systems or secondary functions affected

There were no other systems or secondary functions affected by this condition.

F. Method of discovery of each component or system failure or procedural error

The failure of 2-RM-90-130 was identified while preparing to place Unit 2 Purge in service.

G. Failure mode, mechanism, and effect of each failed component A failed high voltage power supply was the cause of 2-RM-90-130 being inoperable.

H. Operator actions

Upon determining that 2-RM-90-130 was inoperable, Unit 2 entered TS LCO 3.3.6 Condition B, and TS LCO 3.6.3 Condition A. To comply with LCO 3.6.3 Condition A, a dedicated operator vyas assigned to close lower compartment purge valves 2-FCV-30-37 and 2-FCV-30-40 in the event of a CVI signal. Additionally, AnnunciatorVerification procedure, 2-PI-OPS-ANN, was initiated to account for all annunciators.

l. Automatically and manually initiated safety system responses

There were no safety system responses initiated as a result of this condition.

lll. Cause of the Event A. Cause of each component or system failure or personnel enor It was determined that the malfunction of 2-RM-90-130 was due to a failed high voltage power supply associated with the instrument's ratemeter.

B. Cause(s) and circumstances for each human performance related root cause

During dayshift on July 26,2018, work was being performed to support replacement of the Containment Upper Compartment Monitor (1-RM-90-112). This work was being performed in panel 0-M-12, and resulted in several spurious alarms for the Waste Disposal System Gas Effluent Monitor (0-RM-90-118). The Unit Supervisor (US) directed the craft to stop work until a plan could be put in place to minimize the impact to other RMs in panel 0-M-12. The instrument malfunction ANN 193-D alarm associated with 2-RM-90-130 was received in the MCR at the same time the spurious alarms on 0-RM 118 were received. This contributed to the failure to promptly identify the failure of 2-RM-90-130.

The cause evaluation for this event, determined that TVA's annunciator response process was not being properly implemented. Annunciator Verification procedure, 2-PI-OPS-ANN, was not being performed as designed. Per procedure, annunciator verification is performed once per shift while in Mode 1. However, two shifts of licensed operators did not properly implement the guidance for annunciator response.

lV. Analysis of the Event The containment purge air exhaust monitors are gaseous effluent monitors which continuously monitor the radioactivity in the exhaust air from the containment atmosphere. The primary safety function is the mitigation of the off-site dose consequences for the small loss of coolant accident.

Since these are redundant safety-related monitors, there was no loss of safety function, as 2-RM-90-131 remained operable for the duration of the LCO applicability.

V. Assessment of Safety Consequences

There was no loss of safety function, as redundant monitor, 2-RM-90-131, remained operable for the duration of the LCO applicability. Therefore, there was no significant impact to the health and safety of the public from this event.

A. Availability of systems or components that could have performed the same function as the components and systems that failed during the event Redundant monitor, 2-RM-90-131, remained operable forthe duration of the LCO applicability.

B. For events that occured when the reactor was shut down, availability of systems or components needed to shut down the reactor and maintain safe shutdown conditions, remove residual heat, controlthe release of radioactive materia!, or mitigate the consequences of an accident Systems and components required to maintain safe shutdown conditions were available during the event.

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 2-RM-90-130 remained inoperable from 1007 on June 26, 2018 until Unit 2 exited TS LCO 3.3.6 Conditions A and B, and TS LCO 3.6.3 Condition A at 2300 on August 2, 2018.Page 5 of 6(04-2018))

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET NO. 3100-0104 EXFIRES1 O3t31t2020 Estimahd burden per response to comply witr this mandatory oolleclion rEuest 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.

Reportsd lessons learned re incorporabd inb the lioensing process and ftd back b industy. Send comrnenb regarding burden estimate h fie lnformation Servioes Branch [t-2F431, U.S. Nucbar Regulabry Commission, Washingbn, DC 2055$0001,0r by +mailb lnfocoflecb. Resource@nrc.gov, and h fie Desk fficer, Offce of lnfurmalion and Regulatory Affairc, NEO&10202, (315S0104), ffice of Management and Budget Washingbn, DC 20503. lf a means used b inpose an infwmation collecdon does not display a cunenty valid OMB contd number, fie NRC may not conduct or sponsor, and a person is not rcquired b respond b, the information collection.

{. FACILIW NAME Watts Bar Nuclear Plant, Unit 2

2. DOCKET NUMBER 05000391

3. LER NUMBER YEAR 2018 SEQUENTIAL NUMBER 004 REV NO.

- 00 NARRAT!VE Vl. Corrective Actions This condition was entered into the TVA Corrective Action Program (CAP) and is being tracked under CR1434751.

A. lmmediate Corrective Actions Upon discovery, immediate corrective actions included Unit 2 entering TS LCO 3.3.6 Condition B, and TS LCO 3.6.3 Condition A. A review of plant data was conducted to determine when the instrument malfunction ANN 193-D alarmed in the MCR. Additionally, Annunciator Verification procedure, 2-PI-OPS-ANN, was initiated to account for all annunciators.

B. Corrective Actions to Prevent Recurrence or to reduce probability of similar events occurring in the future Shift orders have been issued with temporary actions to reinforce expectations regarding standards. Additionally, for the applicable operations crews' personnel accountability actions have been taken for lack of performance regarding MCR Board walk down standards, annunciator verification, and response.

Vll. Previous Similar Events at the Same Site A review of recent WBN Licensee Event Reports (LER) found one applicable LER, 2015-006-00, Source Range LevelTrip Channels (N-31 and N-32) lnoperable During Plant Startup. This LER details a human performance eror which resulted in a condition prohibited by the plant's TS.

The conective actions for this event included implementing an annunciator verification process, which if followed appropriately, would have prevented the subject event from extending through multiple shifts of plant operation.

Vlll. Additional lnformation There is no additional information.

lX. Commitments There are no new commitments.Page 6 of 6