ML19260C559

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Responds to IE Bulletin 79-14 Re Seismic Analysis for as- Built Piping Sys.Reanalysis of 39 Isometrics Complete. Thirty-two Meet Code Allowables as Built.Seven Exceed Code Allowables.Forwards List of All Isometrics Reanalyzed
ML19260C559
Person / Time
Site: Arkansas Nuclear Entergy icon.png
Issue date: 10/26/1979
From: Trimble D
ARKANSAS POWER & LIGHT CO.
To: Seyfrit K
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
IEB-79-14, NUDOCS 8001070524
Download: ML19260C559 (4)


Text

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ARKANSAS POWER & LIGHT COMPANY PCST CFFiCE BOX 551 UTTLE ACCK. ARKANSAS 72203 (501)371-4000 October 26, 1979 1-109-23 Mr. K. V. Seyfrit, Director Office of Inspection S Enforcement U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011 Subj ect : Arkansas Nuclear One - Unit 1 Docket No. 50-313 License No. DPR-51 IE Bulletin No. 79-14 (File: 1510)

Gentlemen:

As discussed in our October 12, 1979, letter on this subj ect, the following information is provided.

We have completed the reanalysis of the 43 isometrics listed in Attachment II of our September 14, 1979, letter. Of the 43 isometrics, two were eliminated from reanalysis because the portion of the isometric with dimensional discrep-ancies was not safety-related and therefore not seismic. In addition, two other isometrics upon reevaluation were found to be within the acceptance toler-ance. Of the 39 remaining isometrics which were reanaly:ed, 32 were found to meet code allowables as built and 7 exceeded code allowables. Attachment I lists all isometrics reanaly:ed and their disposition.

We are proceeding with design of the modifications in Attachment I. We plan to complete all of the necessary designs so that they can be implemented during the current outage.

Very truly yours, fcw 'k g David C. Trimble Manager, Licensing }bh} DCT: ERG:pw cc: Mr. W. D. Johnson Mr. Victor Stello, Jr., Director U.S. Nuclear Regulatory Commission Office of Inspection S Enforcement P.O. Box 2090 U.S. Nuclear Regulatory Commission Russellville, Arkansas 72801 Nashington, D. C. 20555 veveen vicot.e scur- urur es sysT aoo1070 519

ATTACHMENT I

  • Isometrics Reanalyzed and the Results of the Reanalysis:

A. Containment Penetratien Room Ventilation System Iso. Sheet No. Discosition HBD-38 2 Meets Code HBD-38 4 Meets Code B. Decay Heat Removal System GCB-1 1 Exceeds code allowable (See Note 1) GCB-1 2 Exceeds code allowable (See Note 2) GCB-1 3 Exceeds code allowable (See Note 3) GCB-3 Exceeds code (See Note 4) GCB-4 1 Meets code HCD-3 (7DH-101) Not safety related C. Emergency Diesel Generating System HBD-11 Meets code D. Emergency Feedwater System ESB-2 2 Meets code EBD-11 1 Meets code EBD-11 2 Meets code ESD-11 3 Meets code EBB-2 1 Meets code E. Gaseous Radwaste System HRC-3 (21-LW-47) Meets code F. Main Steam System EBD-1 1 Reevaluated and found to EBD-2 2 be within acceptance criteria EBB-3 Exceeds code (See Note 5) G. Make-up and Purification System CCB-3 Meets code CCB-5 1 Meets code CCB-5 2 Meets code CCB-10 Exceeds code (See Note 6) GCB-2 Meets code 1696 213

H. Reactor Building Spray System Iso. Sheet No. Discosition HCB-6 4 Meets code HCB-6 3 Meets code GCB-12 1 Meets code I. Service Water System HBD-2 Meets code HBD-20 1 Meets code HBD-14 1 Meets code HBD-20 3 Meets code HBD-20 1 Meets code HBD-21 6 Meets code HSD-20 5 Meets code HBD-14 4 Meets code HBD-4 1 Meets code HBD-14 2 Exceeds code (See Note 7) HBD-21 1 Meets code HBD-52 1 (13 SW 154) Meets code HBD-52 2 (13 SW 155) Meets code HBD-53 1 (13 SW 156) Meets code HBD-53 2 (13 SW 157) Meets code J. Chemical Addition System 12-CON-129 Not safety related HCD-6 1 Meets code 1696 214

NOTES:

1. P + W + ME J S y Sy allowable is not met, primarily due to a very high weight stress. The piping can be made to meet the allowables by addition of a spring hanger.
2. P + W + DE > 1.2Sh and P + W + ME > Sy The allowables can be met by converting hanger DH-67 from a E-W restraint into a N-S and E-W restraint.
3. P + W + DE > 1.2 Sh and P + W + ME y Sy The stresses exceed code allowables due to high weight stresses caused by two branch pipes which are not adequately supported.

The piping will meet code with the addition of two spring hangers, one each on isometrics HCC-10 and GCB-12, Sheet 3. 4 P + W + DE > 1.2 Sh and P + W + ME y Sy Pelocation of valve DH-7B caused high weight stresses which can be reduced with the ,.ddition of a spring hanger.

5. P + W + DE 2 1.2 Sh and P + W + ME > S y The piping exceeds code allowables due to being undersupported seismically near CV-2617 and 2667. The addition of N-S snubber and E-W restraint reduce stress to within allowables.
6. P + W + DE > 1.2 Sh and P + W + ME 7 Sy Stresses exceed code allowables at one point. The addition of a guide will reduce the stresses to within allowables.
7. P + W + DE 2 1.2 Sh and P + W + ME > S y The piping exceeds code in one area due to branch not being restrained. Piping will probably meet code requirements by converting hanger SW-21 from rigid hanger into an anchor.

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