ML20084H839
| ML20084H839 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 03/26/1984 |
| From: | Oprea G HOUSTON LIGHTING & POWER CO. |
| To: | Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| NUDOCS 8405080222 | |
| Download: ML20084H839 (3) | |
Text
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The Light NIII%f Ilouston Lig5 ting & Power P.O. Ilox 1700 liouston, Texas 77001 (713) 22h-9211 March 26, 1984 ST-HL-AE-1067 File No.:
G12.189
[O $0Nk Mr. John T. Collins i 'i 31984 %g$ '
I Regional Administrator, Region IV APR -
Nuclear Regulatory Commission 611 Ryan Plaza Dr., Suite 1000
\\g u ub Arlington, Texas 76012
Dear Mr. Collins:
South Texas Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 First Interim Report Concerning the ESF Load Sequencer Logic Design On February 24, 1984, pursuant to 10CFR50.55(e), Houston Lighting &
Power Company (HL&P) notified your office of an item concerning the Engineered Safety Features (ESF) Load Set:uencer logic design.
Upon the loss of offsite power (LOOP), the ESF Load Sequencr.t-initiates a bus strip signal and loads the standby diesel generators on the ESF buses.
In the case of a safety injection signal (SI) immedictely followed by a LOOP or a LOOP immediately followed by an SI, the timing of the bus strip and initiation of the loading sequence results in the first and seccnd loads being applied to the diesel generators without a sufficient ir.tervening time delay.
The result is potential degradation of the standby diesel generator performance and potential failure to establish adequate emergency core cooling following a loss of coolant accident or mair, steam line break.
This deficiency is the result of a change to the ESF Load Sequencer logic design initiated by Bechtel.
HL&P is reviewing the Bechtel recommended corrective action for the scenario of a LOOP followed by an SI.
The corrective action for the other scenario is still being evaluated by Bechtel.
The next report concerning this item will be submitted to your office by June 29, 1984. This report will include a description of the corrective actions to be implemented.
8405080222 840326 7
gDRADOCK05000
) O W2/NRC2/d
Ilouston I.ighting & Power company March 26, 1984 ST-HL-AE-1067 File No.: G12.189 Page 2 If you should have any questions concerning this matter, please contact Mr. Michael E. Powell at (713) 993-1328.
Very truly yours, l'
. Mr r:
Execut'ive Vi resident MEP/ mpg W2/NRC2/d
March 26, 1984 ST-HL-AE-1067 llouston Lightmg & Power C,ompany File Number: G12.189 Page 3 cc:
Darrell G. Eisenhut, Director Brian E. Berwick, Esquire Division of Licensing Assistant Attorney General for Office of Nuclear Reactor Regulation the State of Texas U.S. Nuclear Regulatory Commission P. O. Box 12548, Capitol Station Washington, DC 20555 Austin, TX 78711 Annette Vietti, Project Manager Lanny Sinkin U.S. Nuclear Regulatory Commission Citizens Concerned Acout Nuclear Power 7920 Norfolk Avenue 114 W. 7th, Suite 220
~
Bethesda, MD 20016 Austin, TX 78701 D. P. Tomlinson Robert G. Perlis, Esquire j
Resident Inspector / South Texas Project Hearing Attorney j
c/o U.S. Nuclear Regulatory Commission Office of the Executive Legal Director P. O. Box 910 U.S. Nuclear Regulatory Commission Bay City, TX 77414 Washington, DC 20555 M. D. Schwarz, Jr., Esquire Charles Bechhoefer, Esquire Baker & Botts Chairman, Atomic Safety & Licensing Board.
One Shell Plaza U.S. Nuclear Regulatory Commission Houston, TX 77002 Washington, DC 20555 4
J. R. Newman, Esquire Dr. James C. Lamb, III Newman & Holtzinger, P.C.
313 Woodhaven Road 1025 Connecticut Avenue, N.W.
Chapel Hill, NC 27514-Washington, DC 20036 i
Ernest E. Hill Director, Office of Inspection Lawrence Livermore Laboratory and Enforcement University of California U.S. Nuclear Regulatory Commission P. O. Box 808, L-46 Washington, DC 20555 Livermore, CA 94550 j
j E. R. Brooks /R. L. Range William S.. Jordan, III, Esquire Central Power & Light Cca.pany Harmon & Weiss P. O. Box 2121 1725 I Street, N.W.
Corpus Christi, TX 78403 Suite 506 Washington, DC' 20006 l
H. L. Peterson/G. Pokorny City of Austin Citizens for Equitable Utilities, Inc.
P. O. Box 1088 c/o Ms. Peggy Buchorn Austin, TX 78767 Route 1, Box 1684 Brazoria, TX 77422 J. B. Poston/A. vonRosenberg City Public Service Board P. O. Box 1771 San Antonio, TX 78296 Revised-12/21/83' i
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