05000305/LER-2005-003, Regarding Inadvertent Reactor Protection Trip While Shutdown - Caused by Procedure Adherence Deficiencies and Inadequate Shift Management Oversight

Regarding Inadvertent Reactor Protection Trip While Shutdown - Caused by Procedure Adherence Deficiencies and Inadequate Shift Management Oversight

ML051160189
Person / Time
Site:	Kewaunee
Issue date:	04/19/2005
From:	Lambert C Nuclear Management Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NRC-05-048 LER 05-003-00
Download: ML051160189 (5)

LER-2005-003, Regarding Inadvertent Reactor Protection Trip While Shutdown - Caused by Procedure Adherence Deficiencies and Inadequate Shift Management Oversight

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(B)
3052005003R00 - NRC Website

text

9J NMC Committed to NudearExence Kewaunee Nuclear Power Plant Operated by Nuclear Management Company, LLC April 19, 2005 NRC-05-048 10 CFR 50.73 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Kewaunee Nuclear Power Plant Docket 50-305 License No. DPR-43 Reportable Occurrence 2005-003-00 In accordance with the requirements of 10 CFR 50.73, "Licensee Event Report System", the enclosed Licensee Event Report (LER) for reportable occurrence 2005-003-00 is being submitted.

This letter contains no new commitments and no revisions to existing commitments.

Craig e

Site Vice President, Kewaunee Nuclear Power Plant Nuclear Management Company, LLC Enclosure (1) cc:

Administrator, Region IIl, USNRC Project Manager, Kewaunee, USNRC Resident Inspector, Kewaunee, USNRC INPO Records Center N490 Highway 42

• Kewaunee, Wisconsin 54216-9511 Telephone: 920.388.2560

ENCLOSUREI LICENSEE EVENT REPORT (LER) 2005-003-00 3 pages follow

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 6-30-2007 (6-2004)

Estimated burden per response to comply with this mandatory collection request 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />.

Reported lessons learned are Incorporated Into the licensing process and fed back to Industry.

LICENSEE EVENT REPORT (LER)

Send comments regarding burden estimate to the Records and FOlA/Pdivacy Service Branch (T-5 F52), U.S. Nuclear Regulatory Commission. Washington. DC 2555-0001, or by intemet e-(See reverse for required number of mail to infocollectsenrc.gov. and to the Desk Officer. Office of Information and Regulatory (See rverseAffairs, NEOB-1 0202. (3150-0066), Office of Management and Budget. Washington. DC 20503.

digits/characters for each block)

If a means 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.

FACIUTY NAME (1)

DOCKET NUMBER (2)

PAGE (3)

Kewaunee Nuclear Power Plant 05000305 1 of 3 TITLE (4)

Inadvertent Reactor Protection Trip While Shutdown - Caused by Procedure Adherence Deficiencies and Inadequate Shift Management Oversight EVENT DATE (5)

LER NUMBER (6)

REPORT DATE (7)

OTHER FACILITIES INVOLVED (8)

ISEOUENTAL REV FACILITY NAME DOCKETNUMBER MO DAY YEAR YEAR NUMBER NO MO DAY YEAR 02 20 2005 2005

-- 003 -- 00 04 20 2005 FACILITY NAME DOCKET NUMBER OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR (Check all that apply) (11)

MODE (9)

N

_ 20.2201(b) 20.2203(a)(3)(ii) 50.73(a)(2)(iI)(B) -

50.73(a)(2)(ix)(A)

POWER 20.2201 (d) 20.2203(a)(4) 50.73(a)(2)(iii)'

50.73(a)(2)(x)

LEVEL (IO) 20.2203(a)(1) 50.36(c)(1)(i)(A)

X 50.73(a)(2)(iv)(A) 73.71 (a)(4) 20.2203(a)(2)(i)

_ 50.36(c)l)(il)(A) 50.73(a)(2)(v)(A)

"_ 73.71(a)(5) 20.2203(a)(2)(ii)

_ 50.36(c)(2) 50.73(a)(2)(v)(B)

- _ OTHER 20.2203(a)(2)(iii) 50.46(a)(3)(ii) 50.73(a)(2)(v)(C)

Specify In Abstract below or In 20.2203(a)(2)(iv) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D)

NRC Fon 366A 20.2203(a)(2)(v) 50.73(a)(2)(i)(B) 50.73(a)(2)(vii)

• _ 20.2203(a)(2)(vi) 50.73(a)(2)(i)(C) 50.73(a)(2)(viii)(A) 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(B)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER (Include Area Code)

Robert Revnnells (920) 388-8791 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

MU REPORTABLE I I MANU-REPORTABLE

CAUSE

SYSTEM COMPON ENT FACTURER TO EPIX I

SYSTEM COMPONEN T FA CTURER TO EPIX SUPPLEMENTAL REPORT EXPECTED (14)

EXPECTED MONT H DAY YEAR SUBMSI D

)

I OSUBMISSION I

,I YES (If yes, complete EXPECTED SUBMISSION DATE).

xDATE (15)

ABSTRACT On February 20,2005 while the Kewaunee Nuclear Power Plant (KNPP) was in the Intermediate Shutdown mode, an inadvertent Reactor Protection System (RPS) trip signal was initiated. The RPS signal was initiated when the Lo-Lo Level setpoint (17%) was reached in the "B" Steam Generator (SG). The low level condition occurred while cool-down operations were in progress with SG levels being maintained outside of the normal operating procedure control band.

Operating the plant during the cool-down evolution outside of procedure requirements and inadequate Supervisory/Management oversight of overall plant operations caused this event.

Corrective actions include the enhancement of procedure use and adherence expectations, with the documentation of these expectations recorded in-an existing plant procedure. The Operations crews will be trained and assessed, regarding knowledge of the existing and enhanced procedure use and adherence expectations. Additionally, a simulator exercise will be 'conducted for each operating crew that reinforces the appropriate behavior required to conduct a plant cool-down. The scenario for the simulator exercise will include the obstacles that were encountered during this event. Individual performance issues associated with this event have been addressed.

There were no plant or public health and safety consequences to this event. This report does not describe a safety system functional failure.U.S. NUCLEAR REGULATORY COMMISSION (1-2001 )

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1l DOCKET NUMBER (2)

LER NUMBER (6)

AE (3)

YEA SEQUENTIAL IREVISIONI Kewaunee Nuclear Power Plant 05000305 YEAR NUMBER l

NUMBER 2 of 3 2005 003 00 TEXT (If'more space Is required, use additional copies of NRC Form 366A) (17)

Event Description

On February 20, 2005, while the Kewaunee Nuclear Power Plant (KNPP) was in the Intermediate Shutdown mode, an inadvertent Reactor Protection System (RPS) [JC] reactor trip signal was initiated. The RPS signal was initiated when the Lo-Lo Level setpoint (17%) was reached in the TB" Steam Generator (SG) [SG]. The low level condition occurred while cool-down operations were in progress with SG levels being maintained outside of the normal operating procedure control band.

On February 19, 2005, a plant shutdown was initiated due to the plant's Auxiliary Feedwater (AFW) system [BA] being declared inoperable due to a previously reported system protection design deficiency. The plant shutdown was completed at 0509 hours0.00589 days <br />0.141 hours <br />8.416005e-4 weeks <br />1.936745e-4 months <br /> on February 20, 2005 Subsequent to performing required Hot Shutdown mode surveillance tests and completing plant system preparations for establishing Cold Shutdown conditions, a plant cool-down was initiated at 1111 hours0.0129 days <br />0.309 hours <br />0.00184 weeks <br />4.227355e-4 months <br /> on February 20, 2005. Plant cool-down is accomplished by steaming the'SGs and maintaining secondary water inventory with the AFW system. Prior to the level trip,-until just shortly before the actual signal was generated, only one AFW Pump [P] was being used to maintain SG level.

Prior to and at the onset of the cool-down evolution, Control Room [NA] operators were experiencing difficulties maintaining SG levels within the procedure-required operating band of 30%,to 50%. Attempting to maintain SG inventory by use of only one AFW pump complicates maintaining level control. When only one AFW pump is used to maintain SG inventory, the operator has limited control over how much flow can be directed to either of the plant's SGs when feeding both at one time. Consequently, if care is not taken to start a second pump soon enough, level control can be lost. In this event, corrective actions to start a second pump to replenish the depleting VBW SG inventory were not accomplished before the Lo-Lo level setpoint was reached.

During cool-down operations, using two motor [MO] driven AFW pumps provides better control of AFW feed flow to each SG. Each of the pumps has an airoperated discharge flow control valve [FCO] whereby the Control Room operator.can control the output flow of the' associated AFW pump. KNPP's system design is such that the discharge piping of the motor driven AFW pumps can be cross-connected to allow one pump operation to feed both SGs. However, the cross-connect piping connection is downstream of the air operated flow control valves for the pumps.' The cross-connect line between the two trains of piping to the SGs is isolable by closing either one or both of two motor operated valves from the Control Room.

In addition to the less than optimal AFWsystem alignment, otheractivities that were in process either aggravated the level control difficulties or distracted the on-shift crew. They include:

Increasing secondary side SG blowdown flow to 50 gpm without notifying the Control Room operator.

• Allowing a SG level of 22%, which is lower than the normal control band limit of 30-50%.

• Attempting to recover from a pre-cool-down evolution that resulted in having to operate one of the SG's in an unusual condition.

• The Control Room Supervisor and Shift Manager were overly interactive with plant activities resulting in distraction from their primary oversight activities.U.S. NUCLEAR REGULATORY COMMISSION (1-2001)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1l DOCKET NUMBER (2)

LER NUMBER (6)

PAGE (3)

YE I SEQUENTIAL I REVISION I Kewaunee Nuclear Power Plant 05000305 YEAR l

NUMBER l

NUMBER 3 of 3 2005 003 00 TEXT (Iftmore space is required, use additional copies of NRC Form 366A) (17)

Event Analysis

This event is being reported under 10CFR 50.73(a)(2)(iv)(A), an event that resulted in automatic actuation of the RPS. The RPS was actuated by the inadvertent initiation of a reactor trip signal when the Lo-Lo Level Setpoint was reached in the MB" SG. The plant had already been placed in a shutdown condition. Therefore, no actual reactor trip occurred.

There is no safety significance to this event. The reactor protection signal was not required to provide any plant or public health and safety need.

Cause

A root cause evaluation of this event was conducted and determined that this event was attributed to failure to adhere to procedure requirements and inadequate Supervisory/Management oversight.

The operations crew exhibited a procedure usage culture that permitted the crew to misapply procedure steps with the knowledge, endorsement, and direction of shift management. Additionally, the Shift Manager and Control Room Supervisor did not maintain appropriate crew oversight during a non-routine transient condition.

Corrective Actions

1. Individual performance issues associated with this event have been addressed.

2. Procedure use and adherence expectations will be enhanced.

3. Operations crews will be trained and assessed, regarding knowledge of existing and enhanced procedure use and adherence expectations.

4. A simulator exercise will be conducted for each operating crew that reinforces the appropriate behavior required to conduct a plant cool down. The scenario for the exercise will include the obstacles that were encountered during this event.

SIMILAR EVENTS

None.