ML20012C374

LER 90-012-00:on 900127,central Alarm Station Operator Noted That Controlled Access Door Not Closed.Caused by Inappropriate Action Taken Which Was Unauthorized.Personnel Counseled on Importance of Sys operability.W/900313 Ltr

ML20012C374
Person / Time
Site:	Catawba
Issue date:	03/13/1990
From:	Glover R, Owen T DUKE POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-90-012-01, LER-90-12-1, NUDOCS 9003210140
Download: ML20012C374 (9)

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March 12', 1990 t

E m- Document Control Desk U. S. Nuclear Regulatory Commission (

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Subject:

Catawba Nuclear Station

• Docket No. 50-413 LER 413/90-12  ;

. Gentlemen:

Attached is Licensee Event Report 413/90-12, concerning TECHNICAL SPECIFICATION 3.0.3 ENTERED FOR BOTH TRAINS OF ANNULUS VENTILATION '

SYSTEM INOPERABLE DUE TO A CONTROLLED ACCESS DOOR FOUND OPEN AS A RESULT OF- AN INAPPROPRIATE ACTION. '

2 This event-was considered to be of no. significance with respect to tho  ;

l health and: safety of-the public.

Very truly yours,

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' Tony B.-Owen Station Manager keb\LER-NRC.TBO xc: Mr. S. D. Ebneter American Nuclear Insurers Regional Administrator, Region Il c/o Dottie Sherman, ANI Library

'U. S. Nuclear Regulator Commission The Exchange, Suite 245 101. Marietta Street, NW, Suite 2900 270 Farmington Avenue Atlanta, GA 30323 Farmington, CT 06032 M & M Nuclear Consultants Mr. K. Jabbour 1221 Avenues of the Americas U. S. Nuclear Regulatory Commission r New York, NY- 20020 office of Nuclear Reactor Regulation Washington, D. C. 20555 INPO Records Center Suite 1500 Mr. W. T. Orders 1100 Circle 75 Parkway NRC Resident Inspector

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NIME TELEPHONE NUMBER ARE A CODE j R.M. Glover, Compliance Manager 8 1 01 3 813 11 l- 1 3121316 COMPLETE ONE LINE FOR E ACH COMPONENT F AILURE DESCRIBED IN THIS REPORT H31 CAUSE SYSTEM COMPON E NT MA AC- RE' CAV$E Sv 8T E V COMPON%T "" "U "I' " '

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~} vts uo r na. intereo sunwssion od rei ~) NO l l l Aes,R ACT ev-., ra um a . i. . m.-.w, r.<, ,. .o-a no. awi s > os, On January 27, 1990, at 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br />, Unit I was in Mode 3, Hot Standby.

Controlled. Access Door'(CAD) 311, Lower Containment Personnel Air Lock, had been ,.

placed on a continuous fire watch. At approximately 2205 hours0.0255 days <br />0.613 hours <br />0.00365 weeks <br />8.390025e-4 months <br />, the Central Alarm Station (CAS) Operator noted that CAD 311 was not closed. The Security Lieutenant directed the Operator to immediately notify the Security Officer at the hatch area. An Operations (OPS) Control Room Operator (CRO) was notified and Technical Specification 3.0.3 was entered due to the inoperability of the Annulus Ventilation (VE) System. The door was closed at 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />, and the OPS CR0 exited Technical Specification 3.0.3 at that time. Several individuals were interviewed regarding the status of the door during their transits, and Security door alarm typers were reviewed.

It was concluded that the door had been tied i

to the adjacent railing with a rope from approximately 2110 to 2130 hours0.0247 days <br />0.592 hours <br />0.00352 weeks <br />8.10465e-4 months <br />, and again from approximately 2150 to 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />. The cause cf this incident is attributed to inappropriate action taken which was unauthorized. Personnel

)- entering Containment were instructed not to leave the door open. A review of l

CAD doors critical to Ventilation System operability will be completed, as well l

L as distribution of information to all station personnel emphasizing the importance of ventilation system operability.

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M i BACKGROUND 4

The Annulus Ventilation [EIIS:VD] (VE) System is designed to achieve a negative pressure of at least 0.5 inches water gauge (inwg) in the annulus, following a loss-of-coolant accident (LOCA). Following a LOCA event, the VE System i minimizes the release of radioisotopes by filtering and recirculating a large y amount of air relative to the volume discharged. It consists of two j independent, 100 percent capacity trains. Upon receipt of a safety signal, recirculating and discharge dampers are automatically aligned to the Unit vent a until negative pressure is greater than or equal to 0.5 inwg. These dampe: 4

} then modulate to maintain the annulus at a negative pressure of 0.5 inwg.

? In the initial design of the VE System and evaluation of various annulus j conditions, Duke Power developed the CANVENT computer model. CANVENT was used to establish and evaluate various design parameters for the VE System. This i program takes several factors into account, such as pre-LOCA temperature-distributions, post-LOCA temperature distributions, post-LOCA annulus temperature and pressure, and the capability of the VE fans [EIIS:BLO] to achieve and maintain a vacuum in the annulus following a LOCA. Other factors

, included in this program are heat transfer from upper and lower Containment e [EIIS:NH] into the annulus, effects of swelling of Containment, and changes in j annulus air density during a LOCA.

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) Technical Specification 3.0.3 is required to be entered when the Unit is

operating in a condition prohibited by Technical Specifications. This condition 2

exists when a Limiting Condition for Operation is not met except as provided in the associated Action Requirements. It requires that within one hour action 1 shall be initiated to place the Unit in a Mode in which the specification does i not apply by placing it, as applicable, in; a.-At least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />,

b. At least HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and

c. At least COLD SHlfTDOWN within the subsequent 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Technical Specification 3.6.1.8 requires both trains of VE to be operable in ,

-Mode 1, Power Operation, Mode 2, Startup, Mode 3, Hot' Standby, and Mode 4, Hot Shutdown. The Action Requirement is that with one train of VE inoperable,-the train must be restored to operability or the Unit must be in at least Mode 3 within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in Mode 5, Cold Shutdown, within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. Surveillance Requirement 4.6.1.8.d.4 states that at least once per 18 months, it must be.shown that each train of VE can produce a negative pressure of at least 0.5-inwg in the annulus within one minute after the start signal.

This requirement is periodically met by the Annulus Ventilation System Performance Test, PT/1,2/A/4450/03C.

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f Technical Specification 3.6.1.3 requires that each Containment air lock be q, operable in Modes 1 through 4. Surveillance Requirement 4.6.1.3b requires an overall air lock leakage test at least once per 6 months. This test is 7 performed in PT/1,2/A/4200/01F, Lower Containment Personnel Air Lock Leak Rate Test.

Technical Specification 3.7.11 states that all fire barrier penetrations

[EIIS: PEN] separating safety related areas shall be operable at all-times. With any of the required fire barrier penetrations or sealing devices inoperable, r

within one hour either establish a continuous fire watch on at least one side of the affected penetration, or verify the operability of fire detectors [EIIS:XT]

on at least one side of the inoperable penetration and establish an hourly fire watch patrol.

The Fire Detection [EIIS:IC] (EFA) System monitors unattended areas of the plant e for smoke or fire, and alerts personnel of the existence and laation of-a fire. ,

, The EFA System is equipped with a Central Fire Detection Panel that alerts Operators, via an alarm, for specific zones within the plant.

Station Directive 2.12.7, Fire Detection and Protection establishes the requirements and responsibilities to ensure that the fire protection standards comply with applicable Technical Specifications. Operations (OPS) assigns the responsibility of Fire Protection Console Operator (FPCO) the duties of maintenance of the Fire Watch Log and all other assignment of continuous and hourly fire watches by station personnel.

Station Directive 3.1.2, Access to Containment, requires that during periods of Reactor shutdown when frequent access to Containment is necessary, Security personnel shall be posted at the personnel air lock area to collect Security badges and to grant access. Also, when the Unit is in Mode 5, Cold Shutdown, or Mode 6, Refueling, the CADS may be propped open and remote card readers utilized to maintain Security documentation.

EVENT DESCRIPTION On January 27, 1990, Unit I was in Mode 3, Hot Standby. Controlled Access Door (CAD) 311, Lower Containment Personnel Air Lock, had been placed in a continuous fire watch status at 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br />, due to the mechanical lock on the door being taped to facilitate entry into Containment. This action to the lock was taken by direction of Radiation Protection (RP) due to CAD 311 being a High Radiation Area Door. In addition to Security personnel being present at the hatch area, an RP Technician was also present maintaining the Controlled Area Access Log.

Also, due to the increased flow of personnel through the door, Security had located a CAD key beside the CAD access box and the personnel entering were instructed to use the key for entry. At 0750 hours0.00868 days <br />0.208 hours <br />0.00124 weeks <br />2.85375e-4 months <br />, the OPS FPC0 had logged CAD 311 as being in " access" status due to the high personnel traffic flow and the

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register on the typer printout in the CAS, but will not alarm at the CAS panel, All entries and exits are maintained on the alarm typer. An assigned Security Officer was stationed outside the door with a Vital Area' Access Log. Each individual who was authorized access to Unit 1 Lower Containment was " badged into" Containment and " logged out" by surrendering their Security badge to the Security Officer. At 2235 hours0.0259 days <br />0.621 hours <br />0.0037 weeks <br />8.504175e-4 months <br />, the Contral Alarm Station (CAS) Operator noted that CAD 311 was opened (not completely closed) and was instructed by the Security Lieutenant to notify the Security Officer at the hatch area, outside CAD 311. OPS was notified by Security at 2210 hours0.0256 days <br />0.614 hours <br />0.00365 weeks <br />8.40905e-4 months <br /> that the door was found open.

Technical Specification 3.0.3 was entered due to both trains of VE being declared inoperable. The door was closed at 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />. Following this event, the door's mechanical lock was re-enabled. The OPS CR0 exited Technical c Specification 3.0.3 at 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />.

Following the incident, interviews were held with seven workers who entered and exited via CAD 311. During the period from 2110 hours0.0244 days <br />0.586 hours <br />0.00349 weeks <br />8.02855e-4 months <br /> to 2130 hours0.0247 days <br />0.592 hours <br />0.00352 weeks <br />8.10465e-4 months <br /> on January 27, 1990, five workers had noted that the door was tied to the adjacent railing with a 1/4 inch nylon rope. Also, from approximately 2150 hours0.0249 days <br />0.597 hours <br />0.00355 weeks <br />8.18075e-4 months <br /> until 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />, two workers interviewed stated that the door was tied open. One individual interviewed who entered Containment at 2130 hours0.0247 days <br />0.592 hours <br />0.00352 weeks <br />8.10465e-4 months <br />, clearly recalled having difficulty opening the door.and stated that CAD 311 was closed. It is concluded that CAD 311 was closed correctly prior to 2110 hours0.0244 days <br />0.586 hours <br />0.00349 weeks <br />8.02855e-4 months <br />. A review of Security alarm typer door records indicated that CAD 311 was not fully closed from 1818 hours0.021 days <br />0.505 hours <br />0.00301 weeks <br />6.91749e-4 months <br /> to 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />, i.e. the electromagnetic pickup was not engaged.

The review also indicated that no one transiting CAD 311 between 1825 hours0.0211 days <br />0.507 hours <br />0.00302 weeks <br />6.944125e-4 months <br /> and

?225 hours0.0026 days <br />0.0625 hours <br />3.720238e-4 weeks <br />8.56125e-5 months <br /> used the CAD key posted at the door in gaining entry, and no computer '

indications of CAD key use were recorded during this time.

CONCLUSION The continuous fire watch on CAD 311 was initiated at 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br />, on January 27, 1990. The reason given for establishment of the fire watch was that the mechanical lock on CAD 311 was " taped back" to facilitate passage through the High Radiation Area Door. Therefore, personnel entrances and exits for Lower Containment were logged onto a Vital Area Access Log by the Security Officer on duty. At 0750 hours0.00868 days <br />0.208 hours <br />0.00124 weeks <br />2.85375e-4 months <br />, the FPC0 initiated the entry into the Fire Watch Log and noted that CAD 311 was in " access" per the Fire Watch Sign Out Sheet. Station Directive 3.1.2, Section 5.4.4 allows CAD doors to Containment to be propped open only in Modes 5 or 6. During the time period that CAD 311 was tied open, Unit 1 was in Mode 3. At the instruction of the Security Lieutenant, CAD 311 was closed and the mechanical lock was re-enabled to ensure that the door latched.

j In addition, the Security Officer at the hatch was instructed by the Security Lieutenant to ensure that the door was not left open. All required fire watch entries were completed by Security personnel. Following the inter' views of personnel who entered and exited CAD 311 on January 27, 1990, no indication or identification was given as to the placement of the rope on the

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Also, during the period of this fire watch and of this incident, the  :

Security Officers on duty were not able to see CAD 311 completely from their station. They were unable to see the point that the rope was tied, due to the 4 material placed at the platform for contamination / housekeeping control.

It is concluded from interviews and material reviewed that CAD 311 was tied open from approximately 2110 to 2130 hours0.0247 days <br />0.592 hours <br />0.00352 weeks <br />8.10465e-4 months <br />, and again from approximately 2150 to 2215 hours0.0256 days <br />0.615 hours <br />0.00366 weeks <br />8.428075e-4 months <br />. The person (s) responsible for tying the door open could not be determined. This incident is attributed to inappropriate action due to unauthorized actions taken.

Recent analyses by Design Engineering indicated that the VE System would not operate as described in FSAR or Technical Specifications if the " main door to

- the annulus or the CAD door to the upper or lower air locks is left open". Per the Intrastation Letter from T.B. Owen, dated July 5, 1989, all Station Supervisors were instructed to complete a Compensatory Action sheet, (Enclosure 3 of Station Directive 3.1.14, Operability Determination) which would result in the maintenance of the capabilities of the VE System with one or more of the described doors open. The form requires that a person be at the door (s) with communications established with the Control Room. This action would then allow the person to be told immediately to close the door (s) in the event of a LOCA.

' The individuals completing the Compensatory Action sheet must initial the sheet upon completion of the form and that they understand their responsibilities for

^ the actions. Prior to this incident there was no Compensatory Action sheet completed. There were no specific communications capabilities arranged prior to the opening of the CAD 311, although a Security Officer was continually'present.

As a result'of this event, an Intrastation Letter will be issued to emphasize to all employees the importance of CAD position to ventilation system performance and the action to be taken when doors are repositioned. Alternative courses of action will be evaluated to achieve tighter control of CADS critical to ventilation system performance.

A review of the Operating Experience Program (OEP) Database for the previous 24 months identified one incident that involved VE System operability (see PIR 0-C88-0266). This incident resulted in both trains of VE being unable to meet FSAR conditions due to removal of a bypass leakage enclosure plate. The root cause of this incident was attributed to a defective procedure. The tests performed as part of the investigation established the VE System operability limits noted above. These events are similar in nature, although they involve different causes. This reported incident is not considered to be a Recurring

Event per the Nuclear Safety Assurance guidelines. Ventilation system performance and operability issues are receiving close scrutiny. A Task Force has been established to provide closer review of testing requirements; a thorough and systematic review of ventilation system design requirements is underway.

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< .awma ec ra. smru on t i In addition to.the OEP Database review for past VE System inoperability, a '

search was performed to identify fire watch or Technical Specification

' violations pertaining to fire watches and fire barrier integrity. A total of seven reports were identified. Five reports (see IIR C88-003-0, IIR C88-045-1, IIR C88-071-1, PIR 1-C89-0288, and PIR 2-C89-0184) resulted from missed hourly fire watches and two reports (see LER 413/89-02, and LER 413/89-024) resulted in Technical Specification violations- for inoperability of a fire barrier. There were no violations of Technical Specifications pertaining to fire doors or fire barriers during this incident.

CORRECTIVE ACTION IMMEDIATE

1) CAD 311 was closed following direction from the Security Lieutenant.

SUBSEQUENT

1) The mechanical lock on CAD 311 was re-enabled.

1

2) The Security Officer at the hatch was instructed by the Security LieuteAant to ensure that CAD 311 was not left open.

, PLANNED

1) Distribute Intrastation Letter to all station personnel emphasizing

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the following:

a. The requirements that shall be performed when a component such as CAD 311 and other doors critical to ventilation systems' operability are to be left open,

b. Specific references to Station Directive 3.1.14, Operability Determination, as it pertains to completion of Enclosure 3 and specific requirements as mentioned in "a".

c. In regards to the Units 1&2 Lower Containment Personnel Air Lock Doors, the Security officer on duty at the hatch would provide the required responsibility for communication to the Control Room when the door (s) are opened for personnel traffic, as during the initial stages of a Refueling outage, Modes 1-4,

2) Review CADS and ventilation system operation to identify those doors that can impair system performance. Evaluate alternatives for tighter control of these doors during plant modes when ventilation systems operabilities are required.

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SAFETY ANALYSIS 5

.. The incident described by this LER affects operation of the VE System. -The purpose of the VE System is to control the release of fission products that leak r from Containment following a LOCA. During a LOCA, the VE System withdraws air from the annulus, filters it, and then exhausts it to the environment or recirculates it back into the annulus. Exhausting a portion of this air creates a negative pressure in the annulus. The negative pressure assures that fission products leaking from Containment will be collected and filtered before being released to the environment. Control Room and offsite doses are affected by the~

exhaust air flow rate. CAD 311 is part of the annulus pressure boundary.

During a LOCA, having a pressure boundary door open will increase exhaust flow rate and, therefore, increase Control Room and offsite doses.

For the periods when the CAD was open, if the VE System had been required to operate, Control Room and offsite doses would have increased. However, according to Design Engineering, there are two possible mechanisms that may have ,

closed the door in the event of an accident. Closing the door would decrease-the dose consequences associated with this incident. One means of closing the j door was a Security Officer stationed nearby and another means was by the individuals in the area. The Officer was stationed nearby to log persons entering and exiting this area. The Officer was given instructions to close the CAD in the event of a fire, but no specific guidance was given regarding other types of accidents. However, it is reasonable to assume that, if an accident K had occurred and the Officer was notified, he would have checked the door and l-closed it before leaving the area. Another possible means of closing the door P

was by the individuals in the annulus that would exit through this door. If an c accident had occurred and they were exiting the annulus, it is reasonable to

). assume that they would'have closed the door as they were leaving. However, even

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if the door had been closed, it would not have sealed as designed because the latch was taped. A small increase in annulus inleakage would result from not properly latching the door. This amount of additional inleakage would not have significantly increased Control Room or offsite doses.

Even if the door was left completely open there is a possibility that it would have been closed in a timely manner. Emergency procedures (EPs) direct the Operators to check annulus pressure. With the CAD open, the annulus pressure may-not reach its setpoint. The EPs would direct the Operators to check VE damper alignment, and if correct, to investigate further. It is reasonable to assume that station personnel would then have discovered the open CAD and closed it.

Because of the uncertainties associated with the above scenarios and the lack of specific directives regarding the closing of CAD 311, no credit can be taken for personnel actions during this incident. Therefore, Design Engineering has determined that the VE System was inoperable during the periods when CAD 311 was opened.

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It should be noted though that the safety significance of the event in the

((. specific time frame involved was low. When the door was discovered open at 2210-hours, Technical Specification 3.0.3 was entered and the door was closed in five i minutes. During the two periods when the door was open (2110-2130 hours and t' 2150-2215 hours) people were working in the area and returned the door to a O

' closed position in a relatively-short time. The significance of the event is further minimized by the fact that the Unit was in a cooldown for the end of cycle 4 refueling outage and was close to the point of entering Mode 4 (350 '

, degrees F) at these times. Because of the reduced temperature and pressure in the primary system the mass and energy release in a LOCA event would have been less than a full power event.

No fires occurred in the areas surrounding the Unit 1 Lower Containment air lock i-

' or in any nearby zones during the period of this Fire Watch. All required hourly Fire Watch documentation was complete for the period. Had any fires-occurred, operable fire detection instrumentation on both sides of the CAD 311 penetration would have alerted OPS personnel in the Control Room. The alarm would have been investigated and the fire extinguished.

The health and safety of the public were not affected by this incident.

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