ML20009G126

Second Revised Final Deficiency Rept Re Welds on Gas Stripper Module,Initially Reported 801008.Norwalk Fabricators Will Remove Nonconforming Piping.Work Will Be Completed by 820301.Part 21 Applicable to Deficiency

ML20009G126
Person / Time
Site:	Yellow Creek
Issue date:	07/24/1981
From:	Mills L TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
REF-PT21-81 10CFR-050.55E, NCR-YC-100, NUDOCS 8108030353
Download: ML20009G126 (2)

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TENNESSEE V t.LE ?AOTHORITY CHATTANOOGA. TENNESSEE 374o1 400 Chestnut Street. Tower II l 'i @ 410 - ZV July 24, 1981 n, s

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I Mr. James P. O'Reilly, Directo?

Office of Inspection and Enforcement f Lbt 3 L

U.S. Nuclear Regulatory Commissica 7 JgL 31BP ,,,,. 7 Region II - Suite 3100 6- '

l 101 Marietta Street UA '1-- 4 Atlanta, Georgia 30303 \g

Dear Mr. O'Reilly:

N m l YELLOW CREEK NUCLEAR PLANT UNIT 1 - DEFICIF.NT WELDS ON GAS STRIPPER MODULE

- NCR YC-100 - SECOND REVISED FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector M. Thomas on October 8,1980 in accordance with 10 CFR 50.55(e).

. This was followed by our interim reports dated November 6, 1980, and l February 5, 1981. A revision to our March 31, 1981 final report was submitted en April 22, 1981. As discussed with R. V. Celenjak by telephone on July 15, 1981, enclosed is our second revised final report. The reason for this revision is the date which all work will be completed has changed. We consider 10 CFR 21 applicable to this deficiency.

If you have any questions concerning this matter, please get in _ touch..with

D. L. Lambert at FIS 857-2581. _

Very truly yours, -

TENNESSEE VALLEY AUTHORITY s <

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\ \ hub' L. M. Mills, Manager Nuclear Regulation and Safety Enclosure cc: Mr. Victor Stello, Jr., Director (Enclosure)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Comission Washington, DC 20555 -

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ENCLOSURE YELLOW CREEK NUCLEAR PLANT UNIT 1 DEFICIENT WELDS ON GAS STRIPPER MODULE -

NCR YC-100 10 CFR 50.55(e)

SECOND REVISED FINAL REPORT Description of Deficiency During installation of the gas stripper pump module (GSPM) at Yellow Creek Nuclear Plant, a TVA welding inspector noticed several weld deficiencies. For example, fillet welds were found to be undersized with some visible porosity. There also appeared to be a lack of penetration en butt welds. Arc strikes were visible. The GSPM is {

manufactured by Norwalk Fabricators. It was purchased by TVA from Co=bustion Engineering. I '!

Safety I=plications j The failure of the gas stripper pump module could result in release of radioactive gaseous f1ssion products (most notably the noble gases) through the ventilation system. This condition could adversely affect the safety of plant operations.

Corrective Action ,

On March 17, 1981, representatives of Norwalk Fabricators, Combustion Engineering, and TVA cet in Windsor, Connecticut, to finalize an approach to making repairs. It was decided that Norwalk Fabric.ators,-

would supervise the removal of all piping that was joined together,by welds which did not meet the requirements of the applicable ASME Code.

All of the removed piping is to be returned to Norwalk for repairs on:

replacement. This work will be completed by March 1, 1982.

Corrective action to prevent recurrence will be addressed in[ final. ;

resolution to NCR YCN QAB 8101.

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