ML19326C630
| ML19326C630 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 06/16/1978 |
| From: | David Williams ARKANSAS POWER & LIGHT CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| 1-068-8, 1-68-8, NUDOCS 8004240571 | |
| Download: ML19326C630 (3) | |
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REOULATORY INFORMATION DISTRIBUTION CYSTEM (RIDS)
DISTRIDUTION FOR INCOMING MATERIAL 50-313 REC: REID R W ORG: WILLIAMS D 11 DOCDATE: 06/16/78 NRC AR PWR & LIGHT DATE RCVD: 06/21/7 I - DOCTYPE: LETTER NOTARIZED: NO COPIES RECEIVED
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SUBJECT:
LTR 1 ENCL 0 FURNISHING INFO RE D L W"S NOTIFICATION OF MAY 3 & G, 1978, THAT SUBJECT FACILITY"S INCORE DETECTOR UNCERTAINTY USED IN THE PAST MAY BE TOO SMALL.
PLANT NAME: ARKANSAS -- UNIT 1 REVIEWER INITIAL:
XJM DISTRIBUTOR INITI AL:
okoo*************
DISTRIDUTION OF THIS MATERIAL IS AS FOLLOWS ***************++*
GENERAL DISTRIBUTION FOR AFTER ISSUANCE OF OPERATING ' LICENSE.
(DISTRIDUTION CODE AOO1)
FOR ACTION:
DR "u" r nRBit4 BC**LTR ONLY(7)
INTERNAL:
(EG F LF#
TR ONLY(1)
NRC PDR**LTR ONLY(1) a.TR ONLY(2)
OELDin>LTR ONLY(1 )
HANAUER**LTR ONLY(1)
CORE PERFORMANCF BR**LTR ONLY AD FOR SYS & PROJ**LTR ONI.Y ( 1 )
ENGINEERING BR**LTR ONLY(1)
REACTOR SAFETY BR**LTR ONLY(1)
PLANT SYSTEMS BR**LTR ONLY(1)
EEB*>tLTR ONLY(1)
EFFLUENT TREAT SYS**LTR ONLY(
J.
MCGOUGH**LTR ONLY(1)
EXTERNAL:
LPDR'S RUSSELLVILLE. AR**LTR ONLY(1)
TIC **LTR ONLY(1)
NSIC**LTR ONLY(1)
ACRS CAT B**LTR ONLY(16) ln h-IHIS DOCUMENT CONTAINS P00R QUAUTY PAGES s
lISTRIBUTION:
LTR 40 ENCL 0 CONTROL NBR:- 7:31700 ?OO IZE: 2P ocs******************************
THE END 3o04240 D /
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gygy DBCKEf M CDY ARKANSAS POWER & LIGHT COMPANY POST OFFICE BOX 551 UTTLE ROCK, ARKANSAS 72203 (501)371-4000 June 16, 1978 r
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1-068-8 Director of Nuclear Reactor Regulation ATTN:
Mr. R. W. Reid, Chief
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Operating Rector Branch #2
- q U. 3. Nuclear Regulatory Commistion k
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Washington, D. C.
20555 VI
Subject:
Arkansas Power 6 Light Company Arkansas Nuclear One-Unit 1 Docket No. 50-313 License No. DPR-51 In-core Detector Uncertainty (File:
1510)
Gentlemen:
On May 3 and May 5 of this year B 6 W notified AP 6 L that the incore detector uncertainty used in the past may be too small.
A reinvestigation of the incore detector un-certainty by B 6 W using observed operational characteris-tics indicated to B 6 W that a larger uncertainty value should be used.
AP G L had indicated to Mr. Guy Vissing (NRC Project Manager) that per his request, we would in-form the NRC of our proposed course of action in this matter.
We have been evaluating B 6 W's new uncertainty analysis and have concluded that we have insufficient data, to determine its merits.
We have requested additional infhrmation from B 6 W regarding their work.
Further evaluation by us of their work will have to await their response.
In the interim, the auditional uncertainties upon incore de-tector measurements of quadrar.t tilt and imbalance recommended by B 6 W have been included in the plant computer TECALM sub-routine (the program which generates alarms based on tilt and imbalance).
This was accomplished by Software Change Request l
Mx)3s-MEMBER MfDOLE SOLTTH UTILITIES SYSTEM
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1-068-8 ~
Juns 16, 1978 4.
4 No. SEL-1-006-3.
Also, changes to the Power Operation Pro-cedure, OP 1102.04, and procedure OP 1103.17 for hand cal-culations using the. backup incore system have been made which include the new uncertainty valves.
Very truly yours, Daniel 11. Williams Manager, Licensing DiiW:0C:nh J
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