L-86-476, Revises Response to Finding B.1 Noted in Insp Repts 50-250/86-33 & 50-251/86-33.Corrective Actions:Insp & Checkout of Loop Performed & Procedure ONOP-0208.14 Revised to Clarify Channel Spiking Requirements
| ML20214P704 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 11/19/1986 |
| From: | Woody C FLORIDA POWER & LIGHT CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| L-86-476, NUDOCS 8612040315 | |
| Download: ML20214P704 (3) | |
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P. o. BOX 14000, JUNO BE ACH. FL 33408
]h jgp FLORIDA POWER & LIGHT COMPANY NOVEMBER 10 1986 L-86-476 Dr. J. Nelson Grace Regional Administrator, Region 11 U. S. Nuclear Regulatory Commission 101 Marietta Street, N.W., Suite 2900 Atlanto, Georgia 30323
Dear Dr. Grace:
j Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 Inspection Report 250-86-33 and 251-86-33 Revised Response - Finding B.I Florida Power & Light Company (FPL) has reviewed our previous response to the subject inspection repcrt and had discussion with the Turkey Point Senior Resident inspector about his concerns and those of FPL. Based on these discussions, FPL has revised the response to Finding B.I.
There is no proprietary information in the report.
Should you or your staff have any questions, please contact us.
Very truly yours, Y6e/Yf C. O. Woody Group Vice sident Nuclear Energy COW /RG/gp Attochment cc:
Harold F. Reis, Esquire
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Attachment FINDING B 10 CFR 50, Appendix B, Criterion XVI, os implemented by FPL Topical Quality Assurance Report (FPLTGAR-t-76A) Revision 8, TOR 16.0, Revision 4, Corrective Action, requires, in part, that measures be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected.
FPL Quality Assurance Manual, Quality Procedure 16.1, Revision 8, delineotes requirements for assuring that conditions adverse to quality are corrected.
Procedure O-ADM-913, Revision dated May 13, 1986, entitled Corrective Action for Conditions Adverse to Quality, itemizes the mechanisms by which conditions adverse to quality are promptly identified, trccked and corrected.
Off-Normal Operating Procedure (ONOP) 0208.14, Deviation or Failure of Reactor Protection and Safety-Related Hogan Instrumentation Channels, revision dated September 4,1985 states, in section 3.2, that bistables for a failed channel shall be placed in the tripped position within 30 minutes of the failure determination.
Contrary to the above, on July I and July 18, 1986, the licensee failed to take adequate measures to assure that conditions adverse to quality were promptly identified and corrected, in that:
FINDING B.I On July 1,1986, Unit 3 pressure transmitter PT-495 failed for twenty seconds
- resulting in a steam generator water level transient which required prompt operator action to preclude o reactor trip. PT-495 was of unknown quality and its failure resulted in the potential. loss of redundancy for steam flow input to the reactor protective system.
The failure mechanism and its potential for recurrence were not know. The required actions of ONOP 0208.14 were not implemented. Root cause evoluotion and troubleshooting were not pursued until requested by the NRC on July 3,1986.
RESPONSE
1)
FPL concurs with the finding.
2)
Pressure transmitter PT-495 fluctuated low and subsequently returned to normal operation. After the fluctuation occurred, the Plant Supervisor-Nuclear (PSN) took the following actions:
1) he swapped controlling chonnels of steam flow to another channel,2) obtained a Safety Assessment System (SAS) output to determine what was cousing the steam flow fluctuation and,3) sent on operator to inspect the area around the pressure transmitter to determine if some physical cause for the fluctuation could be found. Based on the above, he stabilized the feedwater flow, determined the RG3/012/2
RESPONSE (continued) cause of the steam flow fluctuation was PT-495 and was informed that no physical cause of the fluctuation could be seen except for the presence of a security guard with a two way radio in the area of the pressure transmit ter. During the subsequent 30 minutes following the fluctuation, the bistables were not tripped as this would have disabled the alarm function.
The alarm function is important in determining any further fluctuations which may occur rapidly.
Since no further fluctuations occurred and the pressure transmitter remained in ogreement with its redundant channels, the PSN concluded that the channel was operable, but issued a Plant Work Order (PWO) to the instrument and Control department to check out the cause of the fluctuation. This work request appeared on the hot items list at the plant status meeting the some morning.
Shop tests of a similar model transmitter, and field tests on a similar transmitter installed on the opposite unit indicated that these transmitters do exhibit some susceptibility to radio frequency interference. However, the exact response of the initial fluctuation could not be repeated.
Additionally, resident inspector concerns prompted on inspection and check out of the channel loop. No obnormalities were found. The vendor has been contacted and has stated that momentory fluctuation have been observed at other utilities witn no subsequent adverse operation.
The offected transmitter has been replaced and will be returned to the vendor at his request for o detailed factory examination.
Therefore, for this porticular event, based on the PSN's observations, his previous experience in the I & C department, and subsequent investigation and findings, FPL believes the decisioa to not trip the bistables was justified. However, o careful review of this event indicated that sufficient guidance and information was not available in the control room to base o decision on not tripping the bistables had a PSN with different experience been on shift.
3)
An inspection and check out of the loop was performed and no abnormalities were observed. In addition the offected transmitter has been replaced and the one with the failure will be returned to the vendor for o detailed factory examination.
4)
ONOP-0208.14 was revised on August 28, 1986 to clarify the requirements for channel spiking. In addition, guidance has been provided to the PSNs to have them involve the plant management staff in operability decisions when time and circumstances deem it oppropriate.
5) a) Full compliance for item 3 above will be ocheived by December I,1986.
b) Full compliance for item 4 above was achieved by October 25,1986.
RG3/012/3 f