ML20206U416

Insp Repts 50-413/99-10 & 50-414/99-10 on 990314-0424. Violation Being Considered for Escalated Enforcement Action Noted.Major Areas Inspected:Operations

ML20206U416
Person / Time
Site:	Catawba
Issue date:	05/10/1999
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20206U413	List: ML20206U409 ML20206U416
References
50-413-99-10, 50-414-99-10, NUDOCS 9905250204
Download: ML20206U416 (7)

See also: IR 05000413/1999010

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U.S. NUCLEAR REGULATORY COMMISSION

REGION II

Docket Nos:

50-413, 50-414

License Nos:

NPF-35, NPF-52

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Report Nos.:

50-413/99-10,50-414/99-10

Licensee:

Duke Energy Corporation

System:

Catawba Nuclear Station, Units 1 and 2

Location:

422 South Church Street

Charlotte, NC 28242

Dates:

March 14 through April 24,1999

Inspectors:

D. Roberts, Senior Resident inspector

R. Franovich, Resident inspector

Approved by:

C. Ogle, Chief

Reactor Projects Branch 1

Division of Reactor Projects

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Enclosure

9905250204 990510

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ADOCK 05000413

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EXECUTIVE SUMMARY

Catawba Nuclear Station, Units 1 and 2

NRC Inspection Report 50-413/99-10,50-414/99-10

This specialinspection focused on the integrated efforts of the Catawba Nuclear Station staff to

evaluate, determine the root cause of, and correct a licensee-identified configuration control

problem affecting the Standby Shutdown System from December 16 through 29,1998. The

report covers the resident inspection period from March 14 to April 24,1999. [ Applicable

template codes and the assessment for items inspected are provided below.)

Operations

An apparent violation of previous Technical Specification 3.7.13 [now Selected Licensee

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Commitment item 16.7-9 (Standby Shutdown System)] was identified concerning two

mispositioned electrical circuit breakers that rendered the Standby Shutdown System

inoperable from December 16 through 29,1998. This issue affected both Catawba units.

(Section 02.1; [1 A - eel])

Upon discovery of the mispositioned breakers, licensee personnel promptly restored the

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Standby Shutdown System to operable status and made appropriate notifications to the

NRC in the time period required. (Section O2.1; [1 A, 5A - POS])

The licensee's procedures for operating the Standby Shutdown System during certain

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flood, power, fire, and security events were adequate to maintain equipment protection

and perform their intended functions. Only minor enhancements were needed.

Licensee personnel interviewed were knowledgeable of these procedures and how to

implement them. (Section O3.1; [1C,38 - POS))

The licensee's root cause evaluation provided in Licensee Event Report (LER)

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50-413/98-19 sufficiently developed human performance issues that resulted in the

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mispositioned Standby Shutdown System breakers. The licensee adequately addressed

possible contributing factors in its corrective action program. (Section 08.1; [5B - POS])

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Report Details

Summary of Plant Status

During the period of this event (December 16 through 29,1998) both units were at

approximately 100 percent reactor power.

1. Operations

02

Operational Status of Facilities and Equipment

O2.1 Standby Shutdown SystemlSSS) Inocerable Due to Personnel Error Durina Eauipment

Restoration Process

a.

Inspection Scope (71707)

The inspectors reviewed the circumstances associated with LER 50413/98-19

(previously discussed in inspection Report 50-413,414/98-12), in which the SSS was

determined to be inoperable for nearly two weeks because two circuit breakers in a SSS

motor control center were misaligned. The inspectors discussed this issue with plant

personnel, reviewed SSS operating and test procedures, reviewed the restoration

procedure associated with SSS maintenance activities on December 16,1998, and

reviewed the licensee's immediate corrective actions for restoring system operability.

b.

Observations and Findinas

On December 29,1998, the licensee discovered that two breakers associated with the

SSS were open when they should have been closed. The breakers were F02C, Motor

Control Center 1EMXS Attemate Supply, and R03D, Motor Control Center 2EMXS

Alternate Supply. With the two breakers open, the SSS was inoperable for Units 1 and

2. The licensee determined that the two breakers had been in the incorrect position for

13 days, which exceeded the allowed outage time of seven days before action to initiate

a unit shutdown to Mode 3 (hot standby) was required within the following six hours.

SSS Backaround information

The SSS is a non-safety-related system that is used to cope with certain flood, power,

fire, and security events in order to achieve and maintain hot standby condition for one or

both units. The SSS is utilized for certain events that may result in the loss of normal

reactor coolant pump (RCP) seal injection. This involves a time-critical task to provide

sealinjection with the associated unit's standby makeup pump (which can be powered

from 1SLXG using the SSS diesel) within 10 minutes in order to maintain RCP seal

integrity. Some of the SSS loads are supplied from 1(2)EMXS, which is normally aligned

to the A train 4160 volt alternating current (VAC) vital electrical bus. Procedure

OP/0/B/6100/013, Standby Shutdown System Operations, Revision 41, directs operators

to open breaker 1(2) F01 A associated with 1(2)EMXA, which is powered from 1(2) ETA

(the A train 4160 VAC vital bus), and close breaker 1(2)F03A associated with 1SLXG,

the auxiliary power supply, during postulated events. If power to 1SLXG is lost, the SSS

diesel engine will be manually started to power the SSS loads, assuming the required

breaker alignment is in place. The standby makeup pump suction and discharge

isolation valves are powered from 1(2)EMXS. These valves are normally closed and

would not be capable of opening and providing RCP sealinjection with breakers F02C

and R03D open since they are in series with breaker 1(2)F03A, respectively.

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To ensure that the time-critical task of providing RCP seal injection can be performed

within 10 minutes, the licensee has procedurally minimized the number of breakers that

need to be manipulated (only F01 A and F03A) to transfer power to 1SLXG. With no

procedural steps provided to verify that the third breaker (F02C for Unit 1 and R03D for

Unit 2) was closed, the ability to provide reactor coolant pump seal injection within 10

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minutes could not be ensured.

Personnel Error Durino Eouioment Restoration Procedure Devetooment

The licensee determined that breakers F02C and R03D had been left in the open

position following preventive maintenance on December 16,1998. The normally closed

breakers were tagged and placed in the OFF (open) position in support of the

maintenance. Following completion of the maintenance activities, the tags were

removed from the breakers, but the breakers were left in the OFF position in accordance

with the system restoration procedure, Tag-Out 08-2811. The system restoration

procedure incorrectly specified that the breakers be restored in the open position. The

licensee determined that a senior reactor operator (SRO) who generated the restoration

procedure assumed that, since the breaker was associated with an alternate power

supply, then the normal position of the breaker was OFF. This SRO failed to reference

applicable procedures to verify the normal breaker position. A second SRO reviewed

and approved the tag-out procedure and missed the error. The misaligned breakers

were identified and questioned by another operator on December 29,1998, who was

performing an unrelated procedure validation walk-through.

Operation Management Procedure (OMP) 2-18, Tagout Removal and Restoration

Procedure, Revision 50, Step 6.2, Restoration / Partial Restore Record Sheet, item AA,

states that equipment is to be normally returned to the position specified by a governing

operating procedure checklist, the body of a goveming procedure, or as specified by the

approving SRO based on plant conditions. The i.ispectors determined that the

governing operating checklists for the two SSS breakers were not reviewed when the

operators determined the required restored positions. Discussions with licensee

personnel and review of assot nd Problem Investigation Process report (PIP)

O-C98-4935, revealed that othen possible contributing factors included the fact that the

restoration procedure did not reference OP/1/A/6350/001, Normal Power Checklist,

which specifies the normal operating positions of the breakers; and station drawings did

not accurately depict the breakers' normal operating positions. The inspectors

concluded that these contributors did not cause the human performance error when the

clearance restoration procedure was being developed and approved by the SROs in

support of the December 16,1998, maintenance activities. These items were, however,

properly included in the licensee's corrective action program.

Root Cause Determination

The licensee determined that the root cause for this event was inadequate work

practices. Operations personnel failed to follow the established practice of reviewing

OP/1/A/6350/001, Normal Power Checklist, to determine the correct normal (restored)

position of breakers F02C and R03D. Based on the breakers' labels, operations

personnel wrongly assumed that the normal position of the breakers was open. The

inspectors concluded that the licensee's root cause determination, as well as its

development of possible contributing factors in the corrective action program, was

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comprehensive. Several short- and long-term corrective actions were specified to

restore operability and prevent recurrence. These included specifying, in the equipment

data base and locally at the breakers, that having them in the OFF (open) position would

render the SSS inoperable. Other actions were taken to address the human

performance issues.

Safety Sianificance

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The SSS is not considered safety-related. However, the SSS provides an alternate and

independent means for maintaining the plant in a safe shutdown (for the SSS this is Hot

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Standby [ Mode 3]) condition following certain loss of power, flooding, fire, and security

events that result in the loss of normal RCP seal injection. These events are not

assumed to be concurrent with a design basis accident. Safe shutdown is achieved

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when: (1) the reactor is prevented from achieving criticality; and (2) adequate heat sink

is provided to ensure reactor coolant system pressure and temperature design and

safety limits are not exceeded. Upon a loss of normal RCP sealinjection, the SSS is

placed in service and the associated unit's standby makeup pump is started to provide

seal injection. This is to be accomplished within 10 minutes to ensure that significant

RCP seal damage and a resultant small break loss of coolant accident do not occur.

With breakers F02C and R03D in the wrong positions and not referenced in the SSS

operating procedure, the SSS's ability to perform its intended safety function of

maintaining RCP seal integrity could not be ensured.

Reculatory Sianificance

The inspectors concluded that the SSS was inoperable from December 16 through 29,

1998, without appropriate actions being taken to restore operability within seven days or

perform a plant shutdown within the following six hours as required by Technical

Specifications (TS). [As of January 16,1999, following the licensee's conversion to

improved TS, this requirement was transferred to the Selected Licensee Commitments

(SLC) document (item 16.7-9), considered Chapter 16 of the Catawba Updated Final

Safety Analysis Report.) The licensee's failure to restore SSS operabiity or perform a

plant shutdown within allowed outage times is considered an apparent violation of

previous TS 3.7.13. This is identified as apparent violation (eel) 50-413,414/99-10-01:

Standby Shutdown System Inoperable in Excess of TS Limits Due to Mispositioned

Circuit Breakers.

c.

Conclusions

An apparent violation of previous Technical Specification 3.7.13 [now Selected Licensee

Commitment item 16.7-9 (Standby Shutdown System)) was identified concerning two

mispositioned electrical circuit breakers that rendered the Standby Shutdown System

inoperable from December 16 through 29,1998. This issue affected both Catawba units.

Upon discovery of the mispositioned breakers, licensee personnel promptly restored the

Standby Shutdown System to operable status and made appropriate notifications to the

NRC in the time period required.

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03

Operations Procedures and Documentation

O3.1 SSS Operatina Procedures and Plant Staff Knowledae - General Comments (71707)

The inspectors reviewed procedures associated with the operation of the SSS for loss of

nuclear service water, loss of component cooling water, and station blackout events

(i.e., events resulting in loss of normal RCP seal injection), and interviewed operations

and security personnel responsible for implementation. One minor discrepancy was

identified in OP/0/B/6100/013, Standby Shutdown System Operations, Revision 42.

Procedural steps goveming the transfer to the SSS referenced a wrong structural

' column identification number in describing a critical terminal box location. This item was

communicated to station personnel for correction.

Otherwise, the licensee's procedures for operating the SSS during certain flood, power,

. fire, and security events were adequate to maintain equipment protection and perform

their intended functions. Licensee personnel interviewed were knowledgeable of these

procedures and how to implement them.

08

Miscellaneous Operations issues (40500, 92901)

- 08.1 - (Closed) LER 50-413/98-19-00: Standby Shutdown System inoperable in Excess of

Technical Specification Allowed Outage Time due to Mispositioned Breakers Caused by

Personnel Error

The licensee's root cause evaluation provided in this LER sufficiently developed human -

performance issues that resulted in the mispositioned breakers. The licensee

adequately addressed possible contributing factors in its corrective action program.

Based on the inspectors' review of the subject event, as described in Sections 02 and

' 03 of this inspection report, this LER is closed.

V. Management Meetmgs

X1

Exit Meeting Summary

The inspector presented the inspection results to members of licensee management at

the conclusion of the inspection on May 3,1999. The licensee acknowledged the

findings presented. No proprietary information was identifed.

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PARTIAL LIST OF PERSONS CONTACTED

Licensee

R. Beagles, Safety Assurance Manager

M. Boyle, Radiation Protection Manager

S. Bradshaw, Safety Assurance Manager

G. Gilbert, Regulatory Compliance Manager

R. Glover, Operations Superintendent

P. Herran, Engineering Manager

R. Jones, Station Manager

G. Peterson, Catawba Site Vice-President

F. Smith, Chemistry Manager

R. Parker, Maintenance Manager

INSPECTION PROCEDURES USED

IP 40500:

Effectiveness of Licensee Controls in identifying, Resolving, and Preventing

Problems

IP 71707:

Plant Operations

IP 92901:

Followup - Operations

ITEMS OPENED, CLOSED, AND DISCUSSED

Opened

50-413,414/99-10-01

eel

Standby Shutdown System inoperable in Excess of

TS Liro;ts Due to Mispositioned Circuit Breakers

(Secuon O2.1)

Qloped

50-413/98-19-00

LER

Standby Shutdown System inoperable in Excess of

Technical Specification Allowed Outage Time due

to Mispositioned Breakers Caused by Personnel

Error (Section 08.1)

LIST OF ACRONYMS USED

CFR - -

Code of Federal Regulations

eel

Escalated Enforcement item (Apparent Violation)

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LER

Licensee Event Report

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NRC

Nuclear Regulatory Commission

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PIP

Problem Investigation Process

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RCP

Reactor Coolant Pump

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SLC

Selected Licensee Commitments

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SRO

Senior Reactor Operator

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SSS

Standby Shutdown System

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TS-

Technical Specification

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VAC -

Volts Attemating Current

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