ML20141A448
| ML20141A448 | |
| Person / Time | |
|---|---|
| Site: | Portsmouth Gaseous Diffusion Plant |
| Issue date: | 05/09/1997 |
| From: | Allen D UNITED STATES ENRICHMENT CORP. (USEC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GDP-97-2005, NUDOCS 9705140305 | |
| Download: ML20141A448 (7) | |
Text
Unit d Stit:s Enrichment Corporation 2 Democracy Center 6903 Rockledge Drive Bethesda. MD 20817 Tel. (301) 564-3200 Fax:(301) 564-3201 Ottitcal 5,f atty E irichriierit Corp >ratiori May 9,1997 GDP-97-2005 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 Portsmouth Gaseous Diffusion Plant (PORTS)- Docket No. 70-7002 - Event Report 97-05 Pursuant to 10 CFR 76.120 (c)(2), Enclosure 1 provides the required 30 day written Event Report (ER) for an event involving multiple fire protection system supervisory alarm failures. Enclosure 2 is a list of commitments made in the report.
Should you require additional information regarding this event, please contact Scott Scholl at (614) 897-2373.
Sincerely, (3 ale Allen, l
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General Manager DIA:SScholl:cw Enclosures (2) i cc.
NRC Region 111 C. Cox/D. Ilartland, NRC Resident inspectors, PORTS j
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PDR ADOCK 07007002; C
PDR Omces in Paducah, Kentucky Portsmouth, Ohio Washington. DC
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- United States Nuclear Regulatory Commission.
May 9,1997 Page Two -
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Distribution 1
Robert L. Woolley i
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'J. Adkins, liq J. Anzelmo,' PORTS M. Boren, PGDP.
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. N. Boesch, PORTS :
' S. Brawner, PGDP i
-iJ. Dietrich, LMUS ~
-f L L. Fink, PORTS.
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~ R. Gaston, PORTS i
. M. Ilasty, PORTS P.'liopkins, PORTS.
J. Labarraque, PGDP 4
B. Lantz, PORTS -
1 R. Lipfert, PORTS R. D. McDermott, PORTS J. Miller, IlQ J. Mize, PGDP J. Morgan, PORTS J. Parker, PORTS.
1 A. Rebuck-Main, IIQ S. Routh, HQ l
~ S. Scholl, PORTS C. Sheward, PORTS i
B. Snook, PORTS B. Sykes, PGDP R. Wells, IlQ
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- K. Zimmermann, PORTS j
PORTS Record Management
. RM: PORTS 97-890-098 i
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e Docket No. 70-7002 j
Page1of4 Event Report 97-05 i
Description of Event On April 9,1997, at 1045 hours0.0121 days <br />0.29 hours <br />0.00173 weeks <br />3.976225e-4 months <br />, while performing a self assessment of the Fire Services surveillance testing program, Fire Services personnel discovered that the supervisory alarm for Post Indicator Valve (PlV) #292, located in the X-330 facility, failed to meet the operability requirements of Technical Safety Requirement (TSR) 2.2.3.4, "High Pressure Fire Water System." Surveillance Requirement SR 2.2.3.4.7 requires annual verification that the supervisory alarm actuates when the PlV is closed. The surveillance test performed on March 13,1997, indicated that the supervisory alarm did not actuate as required when the valve was manually closed. At the time of this failure, Fire Service personnel did not believe that the failure of a supervisory alarm affected operability of the entire sprinkler system. As a result, the plant operated from March 13,1997 to April 9,1997, without taking the required actions of TSR 2.2.3.4, Condition A, The failure of the PlV #292 supervisory alarm to perform its design function, while the plant was in an operational mode that required the PIV to be operable, is reportable in accordance with 10CFR76.120(c)(2).
Immediately following the discovery of the above supervisory alami failure, Fire Protection personnel determined that there were an additional 56 PIV supervisory alarms known to be malfunctioning but had not been declared inoperable. These 56 failures f35 in the X-333 and 21 in the X-330 buildings) resulted from testing that was performed prior to March 3,1997, which is the date that TSR 2.2.3.4 became effective.
As a result of the above discoveries, the PSS declared the Hig'.1 Pressure Fire Water System (IIPFWS) supervisory alarms in the X-326, X-330 and X-333 facilities inoperable. In accordance with TSR 2.2.3.4 and TSR 2.7.3.3, all hot work activities in the affected buildings were immediately suspended. The supervisory alarms remained inoperable until repairs could be made. All 247 PlV supervisory alarm surveillances associated with the X-326, X-330 and X-333 were performed. The surveillances were completed successfully by April 10,1997.
PlVs are control valves and are located in the lead-in to each sprinkler system. The valves are equipped with tamper alarms supervised from the Fire Station. PIVs are monitored in the open position using a micro switch installed on the side of the valve. If the valve is closed, the switch activates an alarm panel at the Area Control Room (ACR). The panel has a power supply that supplies power to the micro switch on the PlV and it monitors PlV loops. The panel also has an input that activates a coding transmitter and when the micro switch on the valve opens, the coding transmitter sends a code to the Fire Station that alerts them that the PIV is closed.
a Docket No. 70-7002' Page 2 of 4 Event Report 97-05 Cause of Event The direct cause that 21 PIV supervisory alarms in the X-330 failed was due to three inoperable
, micro switches, manufactured by Potter, model stock number 101025. The reason the three switches were inoperable was one switch was defective, one switch was out of adjustment and the third switch had been disconnected on February,25,1997, for valve repair and not reconnected. The direct cause the 35 PIV supervisory alarms in the X-333 failed to actuate was due to a defective relay in the programmable coder, manufactured by Gamewell, model number 30350-10, located in the Gamewell Flex Alarm 3000 panel, at the ACR. There were no failures associated with the supervisory alarms in the X-326.
The root cause for the supervisory alarm failures is that past maintenance practices were not adequate to ensure reliable alarm operation. Prior to March 3,1997, the supervisory alarm system was not relied on to meet operability requirements for the HPFWS. When failures occmted they were treated as lower priority work because they did not affect the ability of the IIPF WS to suppress a fire. Failures were not trended or analyzed to identify opportunities to improve system reliability. As a result, the supervisory alarm system did not meet management's expectations for reliability at the time the TSR became effective.
Prior to March 3,1997, the PlV supervisory alarm testing was performed as part of the preventive maintenance program. The requirement to perform this testing to demonstrate HPFWS operability did not exist until TSR 2.2.3.4 became effective. The nomial plant practice prior to March 3,1997, was to initiate a Maintenance Service Request (MSR) when a supervisory alarm failure was discovered. These failures were not reported to the PSS for operability evaluations since the failed supervisory alarms did not impact the ability of the IIPFWS to perform its design function.
As part of the plant's preparations for transitioning to the new requirements of TSR 2.2.3.4, a review of past test data was performed to verify that the new TSR surveillance requirements would be met when TSR 2.2.3.4 became efTective, liowever, as a result of an error by Fire Services pers.mel performing this review, incorrect test data was relied on to demonstrate the new supervisory alarm surveillance would be met. Test data for water flow alarms was reviewed instead of the test data for supervisory alarms. Since incorrect data was used, it was not recognized that 56 supervisory alarms had failed and would not meet the new surveillance requirements. As a result, the plant transitioned to the new TSR on March 3,1997, without taking the required actions of TSR 2.2.3.4, Condition A.
The supervisory alarm failure that occurred on March 13,1997, was not reported to the PSS until April 9,1997. When the failure occurred, the Fire Services first line manager (FLM) continued to follow the past practice ofinitiating a MSR without notifying the PSS or documenting the
i Docket No. 70-7002 Page 3 of 4 Event Report 97-05 failure on a Problem Report. This was contrary to the requirements of procedure XP2-GP-GP1034, " Surveillance Tracking and Documentation," which requires that the PSS be notified immediately when acceptance criteria are not met and that a Problem Report be written.
The belief by Fire Services personnel that operability of the IIPFWS was not affected by the failed supervisory alarm contributed to this error. Fire Services personnel reviewed TSR 2.2.3.4 and concluded that none of the required actions applied to a failed supervisory alann. This conclusion was based on the fact that the TSR does not have an action statement corresponding to a failed supervisory alarm. All of the action statements in the TSR are associated with the loss of water flow capabi!!ty. Since the failure of the supervisory alarm did not directly affect water flow capability,it was concluded that none of the action statements applied. Fire services personnel did not recognize that supervisory alarms affect operability of sprinkler systems since l
they provide additional assurance that flow capability will be available when needed.
Corrective Actions 1.
On April 9,1997, three micro switches at X-330 and the programmable coder at X-333 were repaired / replaced following completion of electrical maintenance and post maintenance testing. On April 10,1997, all 247 PIVs in the X-326, X-330 and X-333 were declared operable by the PSS aner completion of surveillances.
2.
By June 30,1997, Engineering will complete an evaluation of the equipment and methods used to provide assurance that the PlVs are in the open position. The evaluation will review actions needed to improve supervisory alarm system reliability and/or alternate methods that could be implemented to achieve the same level of assurance.
Appropriate corrective actions will be developed and implemented.
3.
On April 9,1997, systems engineering initiated a review of test data used to verify that all TSR surveillance acceptance criteria were met prior to transition to the TSRs. Any additional discrepancies that are identified will be documented and appropriate corrective actions taken. This review will be complete by May 30,1997.
4.
By June 23,1997, the requirements of XP2-GP-GP1034, Section 6.3, will be reviewed by Front Line Managers and other appropriate personnel who evaluate surveillance test results. This review will ensure personnel are aware of the actions to be taken when surveillance acceptr.nce criteria are not met.
5.
By June 30,1997, requirements in procedure XP2-GP-GP1034, " Surveillance Tracking and Documentation," that detail actions to take when a surveillance is not met will be included in procedure XP4-SS-FS6022, " Test and Inspection of Wet Pipe Sprinkler System."
l Docket No. 70-7002 Page 4 of 4 Event Report 97-05 6.
By July 30,1997, Fire Services personnel will be trained on the revisions to XP4-SS-FS6022.
l Extent of Exposure ofIndividuals to Radiation or Radioactive Materials There were no exposures to individuals from this incident to radiation or radioactive materials.
Lessons Learned
- An incorrect understanding of the relationship between surveillance requirements and operability requirements led to this event. Personnel did not understand that an LCO is not met unless all specified surveillances are completed successfully. Whenever equipment fails to meet a surveillance test acceptance criteria, the equipment is inoperable, the associated LCO is not met and the appropriate action statement must be taken within the required time.
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- a Docket No. 70-7002 Page1of1 Event Report 97-05 List of Commitments 1.
By June 30,1997, Engineering will complete an evaluation of the equipment and methods used to provide assurance that the PIVs are in the open position. The evaluation will review actions needed to improve supervisory alarm system reliability and/or j
alternate methods that could be implemented to achieve the same level of assurance.
Appropriate corrective actions will be developed and implemented.
2.
On April 9,1997, systems engineering initiated a review of test data used to verify that all TSR surveillance acceptance criteria were met prior to transition to the TSRs. Any additional discrepancies that are identified will be documented and appropriate corrective actions taken. This review will be complete by May 30,1997.
3.
By June 23,1997, the requirements of XP2-GP-GP1034, Section 6.3, will be reviewed by Front Line Managers and other appropriate personnel who evaluate surveillance test results. This review will ensure personnel are aware of the actions to be taken when surveillance acceptance criteria are not met.
4.
By June 30,1997, requirements in procedure XP2-GP-GP1034, " Surveillance Tracking and Documentation," that detail actions to take when a surveillance is not met will be included in procedure XP4-SS-FS6022, " Test and Inspection of Wet Pipe Sprinkler System."
5.
By July 30,1997, Fire Services personnel will be trained on the revisions to XP4-SS-FS6022.