ML20126C769

Final Deficiency Rept CP-92-018 Re Steam Leak Discovered in 3-inch Schedule 80 Lateral Installed SG Blowdown Sys. Initially Reported on 920729.Caused by Porosity in Initial Casting.Item Not Reportable Per 10CFR50.55(e) or Part 21

ML20126C769
Person / Time
Site:	Comanche Peak
Issue date:	12/18/1992
From:	William Cahill, John Marshall TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-PT21-92 CP-92-018, CP-92-18, TXX-92599, NUDOCS 9212230208
Download: ML20126C769 (2)

Text

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~ Log il TXX-92599 Fi1e // 10110 L Z // CP-92 48-E 3 Ref, il 10CFR50,55(e)

TUELECTRIC December 18, 1992

% Ub .m J. Cahill. Jr.

Gum ner beWroa U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES) - UNIT 2 _

DOCKET NO. 50 446 STEAM LEAK IN A 3* SCHEDULE 80 LATERAL SDAR-CP-92-018 (FINAL REPORT)

• Gentlemen:

On July 29, 1292. TV Ele ;tric discovered a steam leak in a 3' Scnedule 80 lateral i n s t a l l e- in the steam generator blowdown system. The last report, logged TXX-92464 dated September 28, 1992, stated that the evaluation would 3

be complete h Novemoer 12, 1992. This letter reports the results of that evaluation.

The Steam Generator Blo w n and Cleanup System is used to cool, depressurize, filter, and remove dissolved solids and radionuclides from the steam generator blowdown. It reduces the water chemistry-and radiation contei.t to acceptable levels so that steam generator b;owdown can be returned to the Condensate System or released to the environment. This system and its function are non-nuclear safety related and the system is not required fr caf e shJtdown.

Metallurgical analy: sis has determined that the deviation in the lateral was caused by porosity in the initial casting. During forging, the porosity was

( deformed and provided a through-path for steam as pressure and temperature

> were increased during Hot Functional Testing, ,

The lateral has been replaced and the other two laterals from the same heat have been radiographed with no anomalies detected. Unit I was notified of this deviation by a Technical Evaluation.

l 23002G 9212230208 921218 Y I PDR ADOCK 03000446 h S PDR 4co s.ouve swen Ln. st cana Tem 7520s

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Page 2 of 2 LThis condition would not produce a catastrophic f ailure of' the lateral, but the hole might slowly enlarge causing increasing leakage over time. During j normal. operation the unidentified leakage monitoring program would providei  ;

indication of the small amount of leakage produced and alert the operator to 11cate and correct the leak. Therefore, this deviation could not create a substantial safety hazard were it to remain uncorrected and'is not reportable pursuant to 10CFR50.55(e) or 10CFR21.

Documentation of this evaluation is available on site for NRC review.

Sincerely,.

William J. Cahill, Jr.

By:

l J'. S. Marshall Generic Licensing Manager JTC/tg c- Mr. J. L Milhoan, Region IV

- Mr. B. E. Holian, NRR Resident inspectors, CPSES (2) s 4

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