ML19274E035
| ML19274E035 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 02/27/1979 |
| From: | Brown S VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 024C, 24C, NUDOCS 7903050240 | |
| Download: ML19274E035 (2) | |
Text
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s VepCO 1
February 27, 1979 Mr. James P. O'Reilly, Director Serial No. 024C Office of Inspection & Enforcement PSESC/LCK:adw:me U. S. Nuc..ar Regulatory Commission Region II Docket No. 50-339 101 Marietta Street, Suite 3100~
Atlanta, Georgia 30303
Dear Mr. O'Reilly:
In accordance with 10CFR50.55(e), the NRC, Region II, was notified on January 8, 1979 that the North Anna Unit 2 Axial Power Distribution Monitor-
'ing System (APDMS) provided by Westinghouse Electric Corporation'does not account for the in-core moveable detector background signal when determining the axial flux shape, Fj(z)..
In our previous letter of February 16, 1979, Serial No. 0248, we pre-sented our final-report on this concern stating that the deficiency would be corrected by implementing administrative procedures requiring the reactor r
coerator on North Anna Unit 2 to review the flux traces used by the APDMS in order to characterize detector background levels and flux amplitude. Also, the APDMS input values would be adjusted in order to conservatively account for the effects of detector background. We explained that these procedures were currently being followed at North Anna Unit 1.
Following the transmittal
.of this letter, your Mr. M. S. Kidd requested this supplemental letter con-cerning the APDMS matter.
'It.is Vepco's opinion that the proposed administrative procedures in our letter of February 16,1979 satisfactorily resolve all potential safety im-plications;and as such, the deficiency caused by the APDMS hardware's in-ability to account for detector. background levels is corrected. However, the operations staff at our North Anna power station is currently considering the possibility of alternate methods of lessening the amount of reactor operator intervention necessary to the correct operation of APDMS. The primary method now being considered consists of possible APDMS hardware / software modifica-tions.-
In any case, the fact remains that all possible safety implications associated with this APDMS problem have been adequately corrected and thus no longer pose a concern.
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5 Mr. James P. OfReilly 2
This' letter is to be considered an addition to ~our final report on this'
-item and no further correspondence is' anticipated.
-Very.tru
- yours, Sam C. Br n, Jr.
Senior Vice President Power Station' Engineering and Construction-cc: Mr. John G. Davis, Acting Director
, 0ffice of Inspection & Enforcement Mr. Harold R.' Denton, Director Office of fluclear Reactor Regulation-t b
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