ML20212F939
| ML20212F939 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 01/02/1987 |
| From: | Tucker H DUKE POWER CO. |
| To: | NRC OFFICE OF ADMINISTRATION (ADM) |
| References | |
| NUDOCS 8701120219 | |
| Download: ML20212F939 (4) | |
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Duxe POWER GOMPANY P.O. DOx 33180 CHARLOTTE, N.O. 28242 (7
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January 2, 1987 U.S. Nuclear Regulatory Commission
' Document' Control Desk 4 Washington, D.C.
20555
Subject:
McGuire Nuclear Station Docket Nos. 50-369, 50-370
Reference:
NRC/0IE Inspection Report 50-369/86-21, 50-370/86-21 Gentlemen:
Pursuant to.10CFR2.201, please find attached a response to the violation which was identified in the above referenced Inspection Report, and in the Notice of Viola-tion issued December 4, 1986. Please note these violations were the subject of the enforcement conference of October 10, 1986.
Very truly yours,
[
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Hal B. Tucker JBD/158/jgm Attachment xc: 'Mr. W.T. Orders NRC Resident Inspector McGuire Nuclear Station
-Dr. J. Nelson Grace, Regional Administrator U.S. Nuclear Regulatory Connaission Region II 101 Marietta St. NW, Suite 2900 Atlanta, Georgia 30323 8701120219 870102 I
PDR ADOCK 05000369 jf,O O
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DUKE: POWER COMPANY McGUIRE NUCLEAR STATION RESPONSE TO VIOLATIONS IN INSPECTION REPORT 1:
50-369/86-21 J0E) 50-370/86-21 AND
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NOTICE OF VIOLATION ISSUED DECEMBER 4,1986
-Violation 50-370/86-21-02, Severity Level IV Technical Specification 3.3.2 requires that the Engineered Safety Features Actua-tion System (ESFAS) instrumentation channels shown in Table 3.3-3 be operable.
Tatle 3.3-3 Item 7.g requires that when the plant is operating in Medes 1 or 2, instrumentation channels be operable to automatically start both motor-driven Auxiliary Feedwater Pumps (AFP) after the trip of all Main Feedwater Pumps (MFP).
Contrary to the above, Unit 2 operated intermittently in Mode 2 from June 18, 1986, until June 25, 1986, with DCB breaker 6B in the open position. As a result, the capability of the 2B motor-driven Auxiliary Feedwater Pump to automatically start after a trip of all MFPs was defeated. Consequently, AFP 2B failed to automatically start upon loss of all MFPs during an' event on June 25, 1986.
RESPONSE
1.
Admission or denial of the alleged violation:
Duke Power admits the violation occurred as stated. However, Duke Power would like to point out that the automatic start of the motor-driven aux-iliary feedwater (CA) pumps on the loss of both main feedwater pumps is an anticipatory start. This anticipatory start aids in operator response to the loss of feedwater transient by initiating CA flow to help maintain steam 3
generator water inventory. This is the only automatic CA pump start disabled when DCB breaker 6B (a non-safety related breaker) is in the open position.
The Low-Low steam generator water level trip is the automatic CA start signal for which credit is taken in the McGuire Final Safety Analysis Report Section 15.2.7, entitled Loss of Normal Feedwater. Flow.
2.
Reason for violation:
After an extensive incident investigation, the reason for DCB breaker 6B being in the open position could not be determined.
4 3.
Corrective steps which have been taken and the results achieved:
As a definite cause could not be established, no appropriate corrective actions were identified.
4.
_ Corrective steps which will be taken to avoid further violations:
IAE personnel will evaluate the need to revise the procedure, " Locating Grounds on Deenergized Electrical Circuits", to include specific verification of breaker position.
5.
Date when full compliance will be achieved:
IAE personnel will have the procedure eva3uation completed by January 15, 1987.
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.Page 2 Violation 369, 370/86-21-01, Severity Level IV 10 CFR 50, Appendix B, Criterion III, Design Control, requires that measures be established to assure that applicable requirements are correctly translated into specifications, drawings, procedures, and instructions and that these measures include provisions to assure that appropriate quality standards are specified and included in design documents.
It also requires that measures be established for the selection and review for suitability of application of materials, parts, equipment, and processes that are essential to safety-related functions.
I Contrary to the above, the licensee's design control program was inadequate as indicated by the following examples:
1.
Design control was inadequate in that the torque switch setting for valves 1NV-7 and 2NV-7, the normal let down isolation valves outside containment, did not meet the design criteria. The valves had a licensee specified torque switch setting of 55 percent of full-rate torque which was lower than the 85 percent specified by the manufacturer to assure that the valves would perform their intended function. As a result, valve INV-7 was not fully operable from 1981.until May 1986, and valve 2NV-7 was not fully operable from 1983 until May 1986, as required by Technical Specification 3.6.3.
2.
Electric motor operators (EMO) for valves NI-9 and NI-10 (Reactor Coolant Cold Leg Injection from the Charging Pumps), for both units were found on May 7-8, 1986, to be insufficiently sized to guarantee opening of the valves under worst case design conditions (maximum differential pressure of 2735 psi). The motor operators for valves NI-9 and NI-10 for both units were originally specified by the manufacturer to be 43 rpm and 190 ft-lbs.
The valves were initially installed on both units with the correct motor oper-ators. Because several valves did not meet required stroke times during Unit 1 preoperational testing, the design was changed by the licensee, resulting in the deficient torque rating of the replacement motor operators.
RESPONSE
1.
Admission or denial of the alleged violation:
r Duke Power admits the violation occurred as stated in LER 369/86-09, Revi-sion 2 dated October 10, 1986.
2.
Reason for violation:
r.
The violation occurred due to design and personnel errors, as detailed in LER 369/86-09-02.
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3.
Corrective steps which have been taken and the results achieved:
- The valve operators were adjusted, replaced, or modified in each case to assure the valves would operate under worst case design conditions. The inspection of all IE Bulletin 85-03 motor operated valves in the field was completed.
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Corrective steps which will be taken to avoid further violations:
As present2d in Mr. H.B. Tucker's letter of November 20, 1986 to Dr. J.N. Grace concerning IE Bulletin 85-03, Duke will expand the scope of our original MOV (motor operated valve) improvement program (as described in the May 16, 1986 letter from Mr. H.B. Tucker to Dr. J.N. Grace) from just the Bulletin 85-03 valves to all nuclear safety-related MOV's that are required to be tested for operational readiness.
5.
Date when full compliance will be achieved:
Changes for valves NV-7, NI-9, and NI-10 (both. units) as described in LER 369/86-09-02 are complete. The program described above (and in Mr. H.B. Tucker's letter of November 20, 1986) is currently being assessed; a schedule for completion of the operability verification will be submitted by February 2, 1987.
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