ML20072D969
| ML20072D969 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 06/17/1983 |
| From: | Goldberg J HOUSTON LIGHTING & POWER CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| ST-HL-AE-965, NUDOCS 8306230460 | |
| Download: ML20072D969 (3) | |
Text
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The Light NE%f Houston Lighting & Power P.O. Box 1700 Houston, Texas 77001 (713)228-9211 June 17 1983 ST-HL-Ad-965 File Number: G9.17/C11.1 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation Nuclear Regulatory Commission Washington D.C.
20555
Dear Mr. Denton:
South Texas Project Units 1 & 2 Docket Nos. STN 50-498, STN 50-499 Pipe Break Design Considerations Houston Lighting & Power Company has followed with interest the activities of the Nuclear Regulatory Commission Staff and nuclear industry on the general question of load combinations and pipe break design basis.
In partice'ar, it is noted that the Staff has expressed a very positive intent to modify the criteria for considering double-ended pipe breaks in primary coolant piping for nuclear steam supply systems of the type incorporated in the South Texas Project (STP).
NRC and industry discussions with the ACRS Subcommittee on Load Combinations on March 29th have provided strong indications of general agreement that there would be a net safety benefit from the deletion of whip restraints and other provisions currently incorporated in plants to accommodate, mechanistically, the effects of postulated double-ended pipe breaks.
Houston Lighting & Power Company concurs with the NRC technical staff and nuclear industry position that provisions for mechanistic double-ended pipe breaks in the primary coolant loop and many other locations in the plant provide no identifiable safety benefit and in many cases have a negative safety impact.
In all cases these design provisions are complex and costly and hamper access for operation, maintenance and inspection.
On the South Texas Project many of these restraints have been designed and fabricated. The Project schedule and budget provide fully for their installation.
Installation of primary coolant loop pipe whip restraints for Unit 1 is scheduled to begin in the immediate future.
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Wll 8306230460 830617 Ij PDR ADOCK 05000490 A
llouston Lighting & Power Company June 17 1983 ST-HL-AE'-965 File No:G9.17/
C11.1 Page 2 It is understood that within the next few months, and certainly prior to the scheduled completion of construction for Unit 1, the Commission will have adopted the changes necessary to permit elimination of primary coolant pipe breaks. Criteria to permit selective elimination of breaks at other locations in nuclear class piping systems may also be forthcoring in the near future.
The objective of this letter is to obtain NRC guidance regarding the following issues:
1.
Elimination of double-ended breaks in Reactor Coolant Loop (RCL)pipingbyleak-before-breakcriteria.
2.
Elimination of double-ended breaks in piping in systems other than the RCL by leak-before-break criteria.
3.
Elimination of all intermediate break postulations arbitrarily selected although otherwise meeting defined stress criteria.
In view of the status of the project, HL&P would welcome NRC advice on how to proceed to take advantage of the new technical information available regarding pipe break consistent with NRC activities to change regulatory criteria. We, therefore, suggest that a meeting with members of your staff may be the appropriate forum for obtaining that guidance in a timely manner.
We will contact Mr. H. Schierling, the Licensing Project Manager for STP, to arrange such a meeting if acceptable to the NRC.
Very truly yours,
.Y.
tj J. H. Goldberg Vice President Nuclear Engineering and Construction LJK/mg
l{ouston Lighting & Power Company June 17, 1983 cc:
G. W. Oprea, 'Jr.
ST-HL-AE-965 J. H. Goldberg File Number: G9.17/
J. G.-Dewease C11.1 J. D. Parsons Page 3 D. G. Barker M. R. Wisenburg R. A. Frazar J. W. Williams R. J. Maroni J. E. Geiger H. A. Walker S. M. Dew J. T. Collins (NRC)'
H. E. Schierling (NRC)
W. M. Hill, Jr.
(NRC)
M. D. Schwarz (Baker &Botts)
R. Gordon Gooch (Baker & Botts)
J. R. Newman (Lowenstein, Newman, Reis, & Axelrad)
STP RMS Director, Office of Inspection & Enforcement Nuclear Regulatory Commission Washington, D. C. 20555 G..W. Muench/R. L. Range
-Charles Bechhoefer, Esquire Central Power & Light Company Chairman, Atomic Safety & Licensing Board P. O. Box 2121 U. S. Nuclear Regulatory Commission Corpus Christi, Texas 78403 Washington, D. C.
20555 H.lL. Peterson/G. Pokorny Dr. James C. Lamb, III City of Austin 313 Woodhaven Road P. O. Box 1088 Chapel Hill, North Carolina 27514 Austin, Texas 78767 J. B. Poston/A. vonRosenberg Mr. Ernest E. Hill City Public Service Board Lawrence Livermore Laboratory P. O. Box 1771 University of California San Antonio, Texas 78296 P. O. Box 808, L-46 Livermore, California 94550 Brian E. Berwick, Esquire William S. Jordan, III Assistant Attorney General Harmon & Weiss for the State of Texas 1725 I Street, N. W.
P. O. Box 12548 Suite 506 Capitol Station Washington, D. C.
20006 Austin, Texas 78711 Lanny Sinkin Citizens for Equitable Utilities, Inc.
Citizens Concerned About Nuclear Power c/o Ms. Peggy Buchorn 5106 Casa Oro Route 1, Box 1684 San Antonio, Texas 78233 Brazoria, Texas 77422 Robert G. Perlis, Esquire Hearing Attorney Office of the Executive Legal Director U. S. Nuclear Regulatory Comission Washington, D. C.
20555 Revision Date 04-29-83
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