ML20010J274

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First Interim Deficiency Rept Re Incorrect QC Evaluation of Fillet Welds,Initially Reported on 810824.Reinspection Revealed 252 Unacceptable Welds.Util Will Determine Corrective Actions.Next Rept Provided by 810203
ML20010J274
Person / Time
Site: Phipps Bend Tennessee Valley Authority icon.png
Issue date: 09/23/1981
From: Mills L
TENNESSEE VALLEY AUTHORITY
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NCR-PBNP-275, NRC-PBNP-275, NUDOCS 8109300207
Download: ML20010J274 (2)


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1 400 Chestnut Street Tower II September 23, 1981 PBRD-50-553/81-26 y1

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Mr. James P. O'Reilly, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission 93 %g' SEP2 7 019876 Y Region II - Suite 3100 s , 1 101 Marietta Street s Atlanta, Georgia 30303 P 4j

Dear Mr. O'Reilly:

PHIPPS BEND NUCLEAR PLANT UNIT 1 - REPORTABLE DEFICIENCY - FILLET WELD QUALITY CONTROL INSPECTION - PBRD-50-553/81-26 (NCR PBNP-275)

Initial notification of the subject deficiency was Inde to NRC-0IE, Region II, Inspector P. A. Taylor on August 24, 1981. In accordance with paragraph 50.55(e) of 10 CFR Part 50, we are enclosing the first interim report on the subject deficiency. TVA anticipates submitting the next report on or before December 3, 1981. If you have any questions, please call Jim Domer at FTS 857-2014.

Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Manager Nuclear Regulation and Safety Enclosure cc: Mr. Victor Stello. Director (Enclosure).

Office of Inspection and Enforcement i U.S. Nuclear Regulatory Commission Washington, DC 20555 l

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'8109300207~810923

{DRADOCK 05000553 PDR

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) ENCLOSURE i

I PHIPPS BEND NUCLEAR PLANT UNIT ONE 10CFR 50.55(e) REPORT NO. 1 (INTERIM)

PBRD-50-553/81-26 (NCR PBNP-275)

I Description of Deficiency Containment wall shell plates have anchor bolt chair assemblies welded to them.: The containment wall plates and chairs are welded to the containment ~ base plates. There are 3840 tillet welds used in joining the steel containment walls, the anchor bolt chair assemblies, and the

containment base plates. A total of 252 fillet welds were evaluated incorrectly and accepted by Quality Control inspectors based on such incorrect evaluations.

Initial discovery of incorrectly evaluated and accepted fillet welds occurred when Quality Control Investigation Report No. 22372 was written on May 14, 1981. It revealed 25 fillet welds undersized. Nonconforming

-Condition Report (NCR) PBNP-236 was generated to correct this condition.

The Nuclear Regulatory Commission letter dated June 30, 1981, contained a Netice of Violation stating that on May 6, 1981, an NRC inspector had discovered two undersized fillet welds. That discovery was assigned Noncompliance Item Number 553/81-05-07.

A reinspection of all 3840 tillet welds was performed, resulting in discovery that 252 accepted fillet welds were identified as having inadequate weld size, stressrisers, and lack of fusion. This NCR was generated to accomplish corrective actions.

The cause of the subject deficiency appears to be the result of inconsistencies in the inspection method currently employed by our

quality control inspectors, i.e.

1.) The equipment used 2.) The inspection and evaluation process

, 3.) Related repeatability factor of individual inspectors Safety Implications The deficiency, had it remained uncorrected, could have lessened the ability of the containment vessel to withstand design seismic loads.

Therefore, during a design seismic event this condition could have jeopardized the safe operation of the plant.

Corrective Action TVA has yet to determine the corrective actions necessary for the resolution of this deficiency and will provide this information in the final response.

The next report on this deficiency will be submitted on or before December 3, 1981.

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