ST-HL-AE-2739, Requests NRC Review & Approval of Analyses Demonstrating Low Probability of Pipe Rupture in RHR Suction Line of Plant & Based on Subj Analyses,Proposes to Eliminate Consideration of Dynamic Effects of Postulated Ruptures.Fee Paid

Requests NRC Review & Approval of Analyses Demonstrating Low Probability of Pipe Rupture in RHR Suction Line of Plant & Based on Subj Analyses,Proposes to Eliminate Consideration of Dynamic Effects of Postulated Ruptures.Fee Paid

ML20207D715
Person / Time
Site:	South Texas
Issue date:	08/09/1988
From:	Rosen S HOUSTON LIGHTING & POWER CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
Shared Package
ML19292J233	List: ML20207D740 ML20207D743 ST-HL-AE-2739, Requests NRC Review & Approval of Analyses Demonstrating Low Probability of Pipe Rupture in RHR Suction Line of Plant & Based on Subj Analyses,Proposes to Eliminate Consideration of Dynamic Effects of Postulated Ruptures.Fee Paid
References
ST-HL-AE-2739, NUDOCS 8808150440
Download: ML20207D715 (4)

Text

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P The Light company P.O. Box 1700 llouston, Texas 77001 (713) 228 9211 Ilouston Lighting & Power - -.. - . - . - ._ -. _ . - - -

August 9, 1988 ST-liL- AE- 2739 File No.: G9.10 10CFR50 App. A, GDC 4 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Soutli Texas Projc:t Electric Generating Station Units 1 and 2 Docket Nos. STN 50-498, STN 50-499 Leak Before Break on Residual Heat Removal (RHR) Suction Line

Reference:

(1) HL&P Letter to uRC, J. H. Goldberg to H.R. Denton, March 12, 1986, ST-HL-AE-1617.

(2) HL&P Letter to NRC, M. R. Wisenburg to V. S . Noonati, November 14, 1986, ST-HL-AE-1784.

(3) HL&P Letter to NRC, M. R. Wisenburg to Document Control Desk, May 26, 1987, ST-HL-AE-2190.

(4) HL&P Letter to NRC, M. R. Wisenburg to Document Control Desk, Hay 29, 1987, ST-HL-AE-2213.

Houston Lighting & Power Company (HL&P) requests Nuclear Regulatory Commission review and approval of analyses demonstrating that there is an

[

extremely low probability of pipe rupture in the Residual Heat Removal (RHR) suction line of the South Texas Project, Units 1 and 2. Based on these analyses, HL&P proposes to eliminate consideration of the dynamic effecte of postulated ruptures in the R.lR suction line. The analyse 1 utilize state of the art leak-before-break (LBB) technology and advanced engineering methods, l as described in Attachnient 1. Att ahment 1 provides the results of the

) detailed fracture mechanics analysis together with a full discussion of material properties and an evaluation to NUREG 1061, Volume 3 criteria. The piping schematic layouts covereo by this evaluation are shown on Figures 5-1, 5-2 and 5-3. Attachment 1 demonstrates that the high energy sections of the cauth Texas Project RMR suction lines for both Units 1 and 2 meet all the specified criteria for break elimination as described in NUREG 1061, Volume 3.

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flouston 1 ighting & Power Company F 10 Page 2 By References (1) and (2), HL&P requested an exemption from the requirements of GDC 4 for dynamic effects associated with postulated pipe ruptures of pressurizer surge line and accumulator line piping. HL&P had numerous meetings with the NRC staff to discuss the LBB program and submitted reports and additional information by a number of letters. Reference (3) provided a chronology of meetings and letters between HL&P and NRC. Reference (4) submitted additional information on the accumulator lines. Based on the review of the submitted information and NRC's independent computations, the staff concluded, in Supplement 4 to UUREG-0781, dated July,1987 that HL&P has provided technical justification, consistent with criteria in NUREG-1061, Volume 3, for not providing protective devices against the dynamic effects of postulated pipe breaks in the pressurizer surge piping and the accumulator piping of South Texas Project Units 1 and 2. The analytical methods and

evaluation criteria used in the LBB work presented in Attachment 1 are the same as those used in the evaluation of the pressurizer surge line and the accumulator line.

Attachment i uses material properties and as-built loads from the RHR suction lines which envelope both Unit 1 and Unit 2; therefore, the conclusions are equally applicable to both STP units. Since the CDC 4 was revised effective November 27, 1987, no exemptions are required. Accordingly, HL&P plans. to apply the results of Attachment 1 to eliminate postulated pipe ruptures and not to install the associated pipe whip restraints on the Unit 2 RHR suction lines. HL&P may also delete the corresponding devices frotu Unit 1 at a future date in accordance with the provisions of 10CFR50.59.

Consequently, HL&P requests the NRC staffs' expeditious review and approval of attachment 1 as required by the revised GDC 4.

As Attachment 1 contains information proprietary to Westinghouse Electric Corporation, it is supported by an affidavit signed by Westinghouse, tne owner of the information. The affidavit sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b) (4) of Section 2.790 of the Commission's regulations.

Accordingly, it is respectfully requested that the information which is procrietary to Westinghouse be withheld from public disclosure in accordance 10CFR Section 2.790 of the Commission's regulations.

Correspondence with respect to the proprietary aspects of the application for withholding or the supporting Westinghouse affidavit should reference CAW-88-065 and should be addressed to R. A. Wiesemann, Hanager of Regulatory &

Legislative Affairs, Westinghouse Electric Corporation, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.

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_ lionston I.ighting & Power Company 10 Page 3~

Also attached is a check for $150 in accordance with 10CFR 170.21.

'If you should have any questions on this matter, please contact Mr.

A. W. Harrison at (512) 972-7298.

h S. Rosen General Manager, Operations Support KC/hg Attachments: 1. .WCAP-ll773, "Technical Bases for Eliminating Residual Heat Removal (RHR) Line Rupture From the Structura', Design Basis for South Texas Project Units 1 & 2" Westinghouse Proprietary Class 2, June, 1988.

Also enclosed is a Westinghouse authorization letter, CAW-88-065, Proprietary Information Notice, and accompanying Affidavit.

2. WCAP-ll774, "Technical Sjases for Eliminating Residual Heat Removal (RHR) Line Rupture From the Structural Design Basis for South Texas. Project Units 1 & 2" Westinghouse Class 3, June 1988.

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- 8 L 2 llouston 1.ighting & Power Cornpany-7 10 Page 4 cc:

Regional Administrator, Region IV Rufus S. Scott Nuclear Regulatory Commission Associate General Counsel 611 Ryan Plaza Drive, Suite 1000 Houston Lighting & Power Company Arlington, TX 76011 P. O. Box 1700 Houston, TX 77001

• Ceorge Dick,- Project Manager U.S. Nuclear Regulatory Commission INPO

< Washington, DC 20555 Records Centar 1100 circle 75 Parkway

+

Jack E. Bess Atlanta, CA 30339-3064 Resident Inspector / Operations c/o U.S. Nuclear Regulatory Dr. Joseph M. Hendrie Commission 50 Be11 port Lane P 0.. Box 910 Be11 port, NY 11713 Bay. City,.TX 77414 Don L. Garrison Resident Inspector / Construction c/o U.S. Nuclear Regulatory Commission P. O. Box 910 Bay City, TX 77414 J. R. Newman, Esquire Newman & Holtzinger, P.C.

1615 L Street, N.W.

Washington, DC 20036

, R. L. Range /R. P. Verret Central Power & Light Company P. O. Box 2121 Corpus Christi, TX 78403 R. John Miner (2 copies)

Chief Operating Officer City of Austin Electric Utility 721-Barton Springs Road Austin, TX 78704 R. J. Costello/M T. Hardt City Public Service Board P. O. Box.1771 LSan Antonio, TX 78296

• Includes 3 copies of Attachments 1&2. All others without attachments except where noted.

Revised 06/15/88 L4/NRC/bm

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