ML20248G940

Response to NRC Re Violation Noted in Insp Rept 50-414/89-19.Corrective Actions:Station Problem Rept Initiated to Examine Feasibility of Using Alternate Means of Venting Reactor Vessel Head

ML20248G940
Person / Time
Site:	Catawba
Issue date:	10/02/1989
From:	Tucker H DUKE POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 8910110100
Download: ML20248G940 (6)

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T Duxe POWER COMPANY P.O. m 33189 -

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' October'2,i1989 r .

ld i U. S. NuclearjRegulatory Commission

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L, Document: Control' Desk l Washington,.D.C. .20555-

Subject:

-Ca'tawba Nuc1 ear' Station '

j , -Docket Nos :50-4131 and 50-414 ,

NRC. Inspection'. Report Nos. 50-413, 414/89-19

' Reply:to Notice of Violation

' Gentlemen:

0'-- Enclosed is:the response to,the Notice of Violation (NRC Inspection Report No.

' 50-414/89-19) issued August 31~, .1989 by Stewart D. Ebneter. The violation concerns inoperability.of both channels of the Reactor Vessel Level-Instrumentation' System.(RVLIS) for Unit 2.

LVery truly. yours, y

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i HalB.-Tucker 7 A . WRC74/lcs.

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xc: !Mr.'S. D. Ebneter-

. Regional:. Administrator Region II'.

101 Marietta Street, NW, Suite 2900

' Atlanta, Georgia 30323 Mr..W. T. Orders NRC Resident Inspector Catawba Nuclear Station 1

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, 4 Response To " Notice Of Violation" NRC Inspection Report No 50-414/89-19 Catawba Unit 2 Reactor Vessel Level Instrumentation System Technical Specification 3.3.3.6 requires that the accident monitoring channels as shown in Table 3.3-10 be operable in Modes 1, 2.and 3. Action Statement b. specifies that with the number of operable accident monitoring instrumentation channels less than the minimum channels operable requirements of Table 3.3-10, restore the inoperable channels to operable status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least hot standby within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Table 3.3-10 shows the total number of channels required for Reactor Vessel Water Level as 2 and the minimum number of channels operable as 1.

Contrary to the above, both channels of Unit 2 Reactor Vessel Water Level instrumentation were inoperable from June 2, 1989 to June 16, 1989, with the reactor in Modes 1, 2 and 3, and the licensee failed to comply with the action statement. The channels were inoperable because the isolation valves for the upper range pressure transmitters were closed on both channels.

(1) Admission or Denial of the Violation:

Duke Power Corapany admits the violation.

(2) Reasons for Violation:

On May 19, 1989, while Unit 2 was in Mode 5, Cold Shutdown, Instrumentation and Electrical (IAE) i personnel calibrated RVLIS under Work Request'5992 SWR using procedure IP/2/A/3122/02, System Calibration Procedure Inadequate Core Cooling Monitor External Analog Transmitters Train A and B. Subsequently, the system was returned to service. On May 21, at 1015 hours0.0117 days <br />0.282 hours <br />0.00168 weeks <br />3.862075e-4 months <br />, Unit 2 entered Mode 4, following the EOC2 refueling outage. On May 23, at 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br />, Unit 2 reentered Mode 5. On May 25, Operations personnel needed the Reactor vessel head vented to ensure accurate drain down for NC level indications from non-RVLIS instrumentation. At this time, the decision was made to disconnect the RVLIS tubing on 2NC279, RVLIS Isolation Valve, on the head and then use that valve for venting. In order to properly isolate RVLIS upper range, 4 valves were closed; 2 root valves at the head area, and 2 Magnex valves outside Containment

[EIIS:NH]. This work was accomplished under Work Request 5345 SWR, using Procedure IP/2/A/3122/02. The work request was left open pending the necessary restoration of RVLIS as requested by Operations L_______________-.____

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personnel. On May 28, Operations personnel discontinued the-venting process'and requested'RVLIS be restored to service. The responsible IAE Supervisor assigned the work to a technician working.at this time, who was l-unqualified to perform this task. The responsible Supervisor made the decision to allow the assigned technician to discuss the restoration actions with a qualified technician over the telephone and to then allow the unqualified technician to perform the work.

Under Work Request 5345 SWR, the unqualified technician reconnected the tubing and opened the root valves at the head. However, he failed to open the two Magnex valves which are outside Containment in the Essential Switchgear Rooms. 1 On May 31, at 2056 hours0.0238 days <br />0.571 hours <br />0.0034 weeks <br />7.82308e-4 months <br />, Unit 2 entered Mode 4. On June 2 at 0043 hours4.976852e-4 days <br />0.0119 hours <br />7.109788e-5 weeks <br />1.63615e-5 months <br />, Unit 2 entered Mode 3. On June 6 at 1458-hours, Unit 2 entered Mode 2 and then reached Mode 1 on June 7 at 0425 hours0.00492 days <br />0.118 hours <br />7.027116e-4 weeks <br />1.617125e-4 months <br />.

On June 16, IAE was performing a monthly walkdown surveillance under Work Request 6845 SWR using Procedure IP/2/A/3122/01A,B, Inadequate Core Cooling Monitor System (ICCM-86) Walkdown Checklist Train A, B.

At this time, it was discovered that the RVLIS upper range indications, even though invalid for the plant conditions, were reading improperly. The upper range indications were reading greater than 90%, when they both should have been reading 60%. Investigation revealed that the two Magnex valves were closed.

Subsequently, both trains of RVLIS were declared inoperable and priority 1 Work Request 10525 IAE was initiated. It was then determined that Technical Specification 3.3.3.6 was violated. One Magnex valve was immediately opened. However, the other valve required guidance from Westinghouse in order to open it. The second valve was opened within 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> of discovery. At this time, both trains of RVLIS were declared operabic. Magnex valves on Unit 1 were satisfactorily inspected and confirmed to be open.

This incident has been attributed to inadequate supervision for assigning unqualified personnel to perform a task. The responsible Supervisor failed to use qualified personnel under the Employee Training and Qualification System (ETQS) program to restore RVLIS to service. The work request, 6845 SWR, required two different procedures (IP/0/A/3890/03, Installation of Instrument Line Fittings and Tubing, and IP/2/A/3122/02).

The technician who performed the work was qualified on the first procedure but was not qualified to perform the second procedure. The Supervisor knew that only valve operations were required for the second

,e procedure, even though the procedure covered very-unique calibrations. He made the decision to' allow an assigned technician to discuss the restoration actions with a qualified technician over the telephone and to then allow the unqualified technician to perform the work. This is not allowed under the ETOS program. The Supervisor elected to shortcut-the process because of the perceived urgency of the work and his belief that the work was of a simplistic nature.

During the telephone conversation, the qualified technician gave guidance to the unqualified technician based on previous experiences with his work. On occasions when he had done this work, only the root valves were closed. The Magnex isolation valves were left open. Upon'having this conversation and reviewing the work request, the unqualified technician came to the conclusion that only the two root valves had been closed. The situation was further complicated by the fact that some necessary restoration steps appeared to be made Not Applicable by an IAE General Supervisor during the isolation work on 5/25/89. It appears as though loops 6390 and E420 restoration steps in step

.10.9.9 were made Not Applicable along with loops 6400, 6410, 6430, and 6440. In reality, the intent was only for the latter to be made Not Applicable, but the steps were N/A'ed by a line out of several steps. A careful review of the isolation steps for the four valves in steps 10.2.1 and 10.2.2 B may have revealed a discrepancy, but there was also some confusion with the way some steps were made not applicable by use of a lineout of several steps.

(3) Corrective Steps That Have Been Taken And Results Achieved:

One Magnex valve for an upper range loop would not open with the D/P conditions. Westinghouse provided guidance and the valve was opened with slight ,

adjustment. Work Request 10526 IAE has been written to  !

further investigate this problem during the next outage. The Magnex valves on Unit 1 were inspected and confirmed to be open. The Magnex valves are manufactured by Autoclave Engineers, Inc., model number 2.5MV9061. This valve is not NPRDS reportable.

As a result of this incident, the responsible IAE Supervisor has been counseled and received appropriate disciplinary action. Also, this incident has been reviewed with all IAE Supervision, with emphasis on ensuring the proper use of qualified personnel, and careful attention to detail in marking steps "Not Applicable." A new procedure has been developed that uniquely describes the requirements necessary when

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either disabling upper-range RVLIS for Reactor vessel head venting, or disconnecting upper-range RVLIS for refueling activities.

The Operations group monthly channel check being performed under PT/1, 2/A/4600/03A, has been revised to verify the. lack of 2 control rcom annunciators indicating RVLIS capillary problems and to verify on the ICCM plasma display that a " malfunction" alarm is not indicated.

The Unit 1 and 2 startup procedures have been revised to verify RVLIS upper and lower ranges values read at the minimum and maximum positions, respectively, on their' scales when all four reactor coolant pumps are in operation.

A station problem report has been initiated to examine the feasibility.of using an alternate means of venting the reactor vessel head.

(4) Corrective Steps That Will Be Taken To Avoid Further Violations:

(1) A new procedure has been developed that uniquely describes the isolation, restoration, and system return-to-service verification requirements necessary when either disabling upper-range RVLIS for accommodating Reactor vessel head venting or disconnecting upper-range RVLIS for refueling activities. Standing Work' Requests 5345 SWR and 6357 SWR will be revised by 09/21/89 to require this new procedure in lieu of requiring IP/1,2/A/3122/02 and IP/1,2/A/3122/01A,B.

(2) By the end of each units upcoming outages (UlEOC4; U2EOC3), the Operations Groups will revise the procedure used to verify RVLIS level on upper and lower ranges with various pump combinations.

(3) Further review of the operational requirements of the RVLIS upper range will be performed with the l

intent of submitting a Technical Specification Change Request.

(4) Training will be provided to Operators by 01/01/91 on the enhanced use of the ICCM Display to understand proper upper and lower range RVLIS values with NC Pumps inservice.

(5) Reemphasis will be made to all station groups by 01/01/91 to ensure that all surveillance are being performed, channel checks are being made properly (readings are as expected), and that any annunciators being used to verify a condition reflect true operational status.

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(6): , Newly developedEDepartment.' guidance:on C . Post-Maintenance Testing-(functional. verification-and retest) will-be implemented by.06/01/90.

(7) The'need to use qualified personnel will be reviewed withfremaining appropriate station supervision by 12/31/89.

(8) Station Directive 4.2.1, development, Approval And Use.of Station Procedures,'will be-reviewed to properly. incorporate. guidance'for 'N/A'ing procedure steps by 12/31/89.

(9) The functional verification process.for instruments maintenance will'be reviewed broadly for all station instrumentation.by 11/01/89.

(5) 'Date When Full Compliance Will Be Achieved:

-Full compliance will be achieved by 01/01/90. The work planned for the-end of each units upcoming refueling.

outages'will enhance the ability'to. prevent this type of event in-the future but will not prevent' full' compliance. prior to'that-date.

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