ML20206D300
| ML20206D300 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 11/14/1988 |
| From: | Gridley R TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| NUDOCS 8811170039 | |
| Download: ML20206D300 (7) | |
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TENNESSEE VALLEY AUTHORITY CH ATTANOOG A. TENNESSEE 374ot SN 157B Lookout Place NOV 141988 U.S. Nuclear Regulatory Comism' ATTN:
D0cument Control Desk Washington, D.C.
20555 centlement In the Matter of
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Docket Nos. 50-327 Tennessee Valley Authority
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50-328 CEQUOYAH NUCLEAR PLANT (SQN) UNITS 1 AND 2 - NRC INSPECTION REPORT WOS. 50-327/88-39 AND 50-328/88 NOTICE OF VIOLATION Enclosed is TVA's response to F. R. McCoy's letter to S. A. White dated October 20, 1988, that transmitted the subject notice of vlotation.
The enclosure provides TVA's response to the nottee of violation. No new commitments are provided in this responso.
If you have any questions, please telephone M. A. Cooper at (615) 870-6549.
Very truly yours, TENNESSEE VALLEY AUTil0RITY st 13 R. Cr ley, Ma ge Nucicar LLconsing and Ret,ulatory Affairs Encionure cc:
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I G811170039 091114 1
PDR ADOCK 0">000327 i((
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PDC An Equal Opportunity Employer i
~2-U.S. Nuclear Regulatory Comisslon fd c.c (Enclosure):
Ms. 3. C. Black, Assistant Director fcr Projects TVA Projects Division U.S. Nuclear Regulatory Comission One White Filnt, North 11555 Rockville Pike Rockvl11e, Maryland 20852 Mr. F. R. McCoy, Assistant Dlrector for Inspection Programs TVA Projects Division U.S. Nuclear Regulatory Comission Region II 101 Marietta Street, WW, Sutto 2900 Atlanta, Georgia 30323 Sequoyah Resident Inspector Sequoyah Nuclear Plant 2600 Isou Ferry Road Soddy Daisy Tennessee 37379 l
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ENCLOSURE RESPONSE TO NRC INSPECTION REPORT NOS. 50-327/88-39 AND 50-328/88-39 F. R. McCOY'S LETTER TO S. A. WHITE DATED OCTOBER 20, 1988 Vloistion 50-327, 328/88-39-01 "A.
Technical Specification 6.8.1 requires that written procedures shall be ertsblished, implemented and maintained covering the activities listed in Appendix A of Regulatory Culde 1.33, Revision 2, including surveillance and test activities of safety related equipment.
Contrary to the above, licensee personnel failed to follow SI-82.2 in the proper sequence while performing work on radiation monitor 2-RM-90-106 on August 31, 1988.
As a result, Unit 2 experienced a Containment Ventilation Isolation when a tent signal was injected into the monitor.
Contrary to the above, Licensee personnel failed to follow SI-83 on September 3, 1988, whlte performing work on 0-RB-90-101.
As a result, an Auxillary Building Isolation occurred.
This is a Severity Level IV Violation (Supplemant I)."
Reason for the violation (Example No.1)
This example occurred because instrument maintenance (IM) personnel performed steps S.3.12.7 and 5.3.12.8 of Surveillance Instruction (SI) 82.2, "Functional Test For Radiation Monitoring System," out of sequence. The purposo of this section of the instruction is to measure voltage across both the A and B train relay contacts of radiation monitor 2-RM-90-106, containment building lower compartment ale monitor. Step 5.3.12.7 requires that tho digital ruitimator (DHM) bo adjusted to measure voltage across the relay contacts.
Step S.3.12.8 instructs IM personnel to request that Operations personnel return the bypass handswitchos to their normal position. However, IM personnel requested that the bypass handowitches be roturned to normal without first verifying that the DKMs wore both selected for voltage measuremont; and the DMM across the A relay contacts was left in the rosistance moasurement position. Therefore, when the bypass swltches wore returned to normal, a current path was created across the A relay contacts: and a spurious contalnment vontLlation isolation (CVI) was generated.
This event was previously reported in licensoo event report (LER) 50-328/88035.
Reason for tha Violat. inn (Exampla No. 21 This example occurred because IM personnel failed to reblock the C channel of radiation monitor 0-RM-90-101 (auxl11ary building isolation (AB1]) when resuming thole performance of 31-83, "Channel Calibration for Radiatlon Monttoring Syntem," on channol C of 0-RM-90-101.
During the performance of S1 83, it was necessary to install and remove auxL11ary sampling equipment in accordance with Technical Instruction (TI) 16. "Larp. Lng Methods." This La necessary to satisfy technical speelfication 3.3.3.10 action requirements for
Providing sampilns capability while the radiation monitor is out of service.
When 31-83 was interrupted to perform TI-16, it was necessary to place handswitch 0-MS-90-136 A3 in the 101B position to block the B channel of 0-EM-93-101 while changing the charcoal filters. When resuming perforrance of SI-83, the IM personnel did not return the hanJswitch to the 101C channel block position before continuing with their calibration of channel C; and, consequently, an ABI occurred.
Although administrative controls were in place, which should have e.nre ed that the block handswitch was returned to the correct position before cwasauing with 31-83, a more basic cause for this event is actually the desir,.1 of the control circuitry. The handswitch used to block 0-RM-90-101 is lutspable of blocking more than one channel at a 6.ime.
When 31-83 was perfotted, all three channels were removed from service, uut only one of the channeis could be blocked. Therefore, two inoperable channels were always unuloekod and could potentially cause an ABI.
This event was previously reported in LER 50-327/88032.
Corrective Steps That Have Been Taken (Example No. 1) operations personnel took immediate corrective action to verify that no high radiation existed, then reset the CVI in tecccdance with system operating j
instruction (301) 30.28.
Corrective Steps That Have Been Taken (Examplo No. 2)
Operations personnel took immediate corrective action 'o11owing the ABI to perform SoI-30.5D for restoration of the ventilation system.
Subsequently, the block handswitch was returned to the C channel block position; and the a
remaining portion of that section of SI-83 was completed without further incident.
Corrective Stops That Will be Taken to Avoid rutther Violations (Exampin No. 1)
To prevent recurrence of this example, plant management has met with instrumentation personnel to discuss this and other recent events in which IM personnel wore directly involved. plint management included in their discussion the lessons learned from these events and reemphasized the need for adherence to procedures to enstre that the potent.lal for futuro events is reduced.
Corrnctiva Steps That Will Bo Taken to Avoid Furt5ar_ Violations (Exaegle No, 2)
To prevent recurrence of this event, SI-83 was revised (inatruction change form 88-1251) to remove the control fuses associated with the trip output of 0-RM-90-101 when performing calibrations on that radiation monitor. The removal of these fuses during tosting, in essen.., provides a block of all three channoin thus preventing a channel that has been removed from servico from causing an ABI.
r Dato When roll core 11ance Will Bo Aehleved (Example No. 1)
SQN is in full compliance.
Date When rull Corpliance Wlll Bo Achieved (Examptu No, 2)
SQN is in full corp 11ance.
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s "Violation 50-327. 328/88-39-02 1
"B.
Technical Specification 3.3.1 requires the reactor instrumentation listed in table 3.3-1 to be operable and that table notation 6 be entered as the Action stateswnt when less than 4 channels of Overpower Dein T Trip or
- ess t.han 4 channels of Overtemperature Delta T Trip are OPERABLE. Table notation 6 requires the inoperable channel be placed in the tripped condition within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> in order for power operation to continue.
I Technical Specif-4 tion 3.3.2 requires the Engineered Safety Features Actuation syete.a : sSFAS) instrumentation channels shown in Table 3.3
- to be OPERABLE ar.d u?. Lable notation 16 be entered as the Action Statement o
when less than 4 c$unnels are OPERABLE. Table notation 16 require'. the inoperable channel to be placed in the tripped condition within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in order for power operation to continue.
contrary to the above, reactor trip channels for Overpower De'ta T channel 4, and overtemperaturs Delta T channel 4 were not p'. aced in the l
tripped condition for 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> while they were in an inorarable condition, and Steam Flow in Two Steam Lines High channel 4 '; s not placed in the tripped condition for 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> and 20 minutes while in an inoperable condition. These channels beer, inoperable when the T Average channel j
associated with these trip and ESFAS channels was placed in an inoperable
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status.
' is is a Severity Level IV Violation (Supplement I)."
A3 mission or Dental of the Alleged Violation TVA admits the violation occurred as stated.
l Reason. for the vin,tation i
This violation occurred because the test director for SI-90.72, "Reactor Trip instrumentation Functionti Test of AT/ravg Channel IV Rack 13 (T-68-67),"
j failed to fully implement the requirements of Administrative Instruction j
( AI) 4 7, "Conduct of Testit.g."
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During the performance of 31-90.72, the channel IV Delta T/ reactor cools,t
=ystem average temperature (Tavg) loop bistables were placcd in the tripped condit.Lon and the associated test switches in test.
Accordingly, the channel was declared inoperable; and limiting conditions for operation (LCO) 3.3.1 and
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3.3.2 were entered.
Later when it was determined that SI-90.72 needed to Je stopped to allow performance of another inst ruction (31-26, "Loss of of fsite i
Power Mith safety Injection - D/C 1A-A Containment Isolation Test"), the test director improperly exited SI-90.72 by restoring only the tripped bistables
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their normal configuration. He failed to also return the associated test switches to their normal configuration. This resulted in LCOs 3.3.1 and 3.3.2 l
being exited with the channel still in an inoperable condition.
Approximately 6.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> had elapsed when Operations personnel identified that the actinn i
j statement requirements of LCOs 3.3.1 and 3.3.2 were not being met.
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AI-47, Section 7.',1,2, "Unplanned Test Stoppage, Exiting Reentering,"
requires that an instruction change be made before placing the system back in its normal configuration. This requirement of AI-47, which would have ensured proper configuration of the bistables and test switchek, was not accomplished. This event was previously reported in LER 50-328/88036, i
revision 1.
i Corrective steps That Have Been Taken and Results Achieved Immediate corrective action was taken upon dLacovery of this condition to place the inoperable Tavs channel IV bistables in the tripped posit.on, thus regaining compilance with LCOs 3.3.1 and 3.3.2.
Additionally, training in the form of crew briefings has been provided to the appropriate IM personnel on l
Al 47, section 7.11.21 the potential effects of typical instrument surveillance testing of technical specification requirements; and the details of this event to reemphasize the necessity for proper connunications.
Corrective Steps That Will Be Taken to Avoid Further Violations As previously committed in LER 50-328/88036, revision 1, the following
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additional actions will be completed to prevent recurrence of this event.
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Training will be provided to licensed Operations personnel ducir4 the requalification program on the significance and origin of the process Protection Racks Channel Test Sequence Violated alarm, which will provide licensed Operations personnel an understanding of the condition of a protection-grade instrument loop during testing.
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Technical specification training will be provided by Nuclear Training for approprLate IM foremen and general foremen by January 20, 1989.
f Date Whwa Wll C++11ene-Will F-Aehleved SQW is in full compliance.
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Violation 50-327. 328/88-33-03 "C.
Technical specification 6.8.1 requires that procedures reconmonded in Appendix A of Regulatory Culde 1.33. Revision 2, be established, implemented, and maintained. This includes maintenance procedures.
l Contrary to the above, Work Plan 7152-01 was inadequate and not properly implemented in that performance of the Work Plan on August 4,1988 l
resulted in a load shed of in "
'.9 kv shutdown board and a l'is of tho board for approximately 20 minutes.
This is a Severity Levol IV Violation (Supplement I)."
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Admission or Denial of the Alleged Violation i
I TVA admits the violation occurred as stated.
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Reason for the Violation This violation occurred because workplan (WP) 7152-01 incorrectly stated that the steps of the WP could be performed in any order.
In actuality, the sequence of steps within a group of steps was not important, but the grouping of these particular steps was. Specifically, it was necessary for certain steps to be completed with the undervoltage X (UVX) control power removed and other steps to be completed with the unaervoltage Y (UVY) control power removed.
The failure to recognize these subtle differences (and 'herefore improper grouping of steps during this performance of WP 7152-07 cesulted in i
the deenergitation of the UVY relays while the UVX relays were already
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doenergized. Consequently, the necessary logic was completed; and a load shed of the 1B-B shutdown tsard occurred.
Additionally, after an initial investigation of the load shed event to determine the immediate cause, it was mistakenly concluded that the pettormance of the WP did not cause the load shed. Consequently, on August 5, 1988, performance of the WP was resumed; ano a second load shedding occurred. This second occurrence resulted from an incomplete assessment of the cause of the first event. This event was previously reported in LER 50-327/88029.
Cure *etiva Steps That flave Been Taken and Results Achieved j
Immediate corrective action was taken by Operations personnel to reestablish 6.9-kilovolt shutdown boar! IB-B following both load-shedding events.
Following the second load shedding event, WP 7152-01 was revised; and the work was completed without further incident.
Additionally, the Modifications Group A supervisor has revlewed this event i
with both the engineer who prepared the WP and the engineer involved in the performance of the WP to stress the importance of proper work sequence and the 1
necessity to ensure that adequato instructions are provided in WPs.
WLth regard to the second load-shedding event, the Plant Reporting Section i
supervisor has reviewed those events with engineers in the Plant Roporting section, Plant Assessment Sectlon, and plant Operetions Review Committen 1
Oversight Section to stress the importance of correctly assessing the immediate cause of such events and the consequences of an incorrect assessment.
Corrective Steps That Will Be Taken to Avoid Further Vlointions To further prevent recurrence of this violatlon, SQN Modifications management has emphasized to all Modifications engLnoers the necessity to provide detailed work Instructions in accordance with AI-19 requiroments, teate When Full Compliance Will Be Achieved l
SQN is in full compilanco.
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