ML040770616

E-Mail Draft RAI on Steam Generator Inspector Report - Attachment 2

ML040770616
Person / Time
Site:	Arkansas Nuclear
Issue date:	12/05/2003
From:	Minns J Office of Nuclear Reactor Regulation
To:	Benne S Entergy Operations
Shared Package
ML040820686	List: ML040770110 ML040770584 ML040770589 ML040770593 ML040770599 ML040770606 ML040770611 ML040770616 ML040820682
References
Download: ML040770616 (5)

Text

Thomas Alexion - Fwd: RAI . . - . .. . . Page i1 From: John Minns To: INternet:SBenne2 @entergy.com Date: 12/5/03 10:13AM

Subject:

Fwd: RAI Enclosed RAls

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Fwd: RAI Creation Date: 12/5/03 10:13AM From: John Minns Created By: JLM3 @nrc.gov Recipients entergy.com SBENNE2 (INternet:SBenne2@entergy.com)

Post Office Route entergy.com Files Size Date & Time Mail MESSAGE 512 12/05/03 10:13AM Options Expiration Date: None Priority: Standard Reply Requested: No Return Notification: None Concealed

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No Security: Standard

Thomnas Alexion -RAI Pg From: John Minns To: INternet:SBenne2@entergy.com Date: 12/4/03 4:04PM

Subject:

RAI Enclosed are RES, please review expediously so that I can close out this item.

C.\W1ND.0WS\TEMP\GW)00001.TMP Page it 11 C:\WINDOWS\TEMP\GW}O0001 .TMP Page Mail Envelope Properties (3FCFAI44.5A0 24:20023)

Subject:

RAI Creation Date: 12/4/03 4:04PM From: John Minns Created By: JLM3 @nrc.gov Recipients entergy.com SBENNE2 (Ithlemet:SBenne2@entergy.corn)

Post Office Route entergy.com Files Size Date & Time ML033004.WPD 6928 12/04/03 04:02PM MESSAGE 523 12/04/03 04:04PM Options Expiration Date: None Priority: Standard Reply Requested: No Return Notification: None Concealed

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REQUEST FOR ADDITIONAL INFORMATION STEAM GENERATOR INSPECTION REPORT FOR ARKANSAS NUCLEAR ONE - UNIT 1

Reference:

Letter (1CAN01 0301) dated January 17, 2003 from Sherrie R. Cotton, Entergy Operations, Inc. to NRC transmitting the 1R1 7 Once Through Steam Generator Inservice Inspection 90 Day Report.

1. In Table 2.1 of the referenced report, volumetric indications are reported at the lower re-roll transitions. What is your assessment concerning the defect mechanism and cause of these indications? Were these indications present during previous inspections or are they new indications? If these volumetric indications are potentially intergranular attack (IGA) related, why are these indications considered a separate population from those indications labeled in Table 2.1 as "volumetric IGA indications in the UTS" which you have shown are not exhibiting growth at the present time?

2. In Table 2.1, please provide a breakdown of "upper rolltransition cracking" in terms of number of axial and circumferential indications. Similarly, please provide a breakdown of "re-roll cracking - Upper Transition (OPB)" and "re-roll cracking - other re-roll indications within the pressure boundary" in terms of the number of axial, circumferential, and volumetric indications."

3. Table 3.1 refers to "TSP cracking circumferential" for which 0.025 gallon per minute (gpm) leakage is projected for the end of the current operating cycle. Table 2.1 makes no mention of this circumferential cracking mechanism at the tube support plates, nor is there any discussion of this mechanism in the report. Were any circumferential indications identified during 1R17, apart from those at the tube ends, tube hard rolls, or tube re-rolls? If so, provide the number, size, and location of these circumferential indications.

4. Tables 2.3 and 2.4 report the condition monitoring leakage estimates for the upper tubesheet tube end cracking (TEC). Table 2.9 reports the condition monitoring leakage estimates for upper tubesheet IGA. Were there other mechanisms that also contributed to total condition monitoring estimate of accident induced leakage? If so, what were the contributions from these other mechanisms? What was the condition monitoring estimate of total accident induced leak rate from all mechanisms?

5. The January 17, 2003 letter reports that the calculated maximum total best estimate LBLOCA leakage is 1.87 gpm. Describe the basis by which this leakage was determined to be acceptable; i.e., that this best estimate leakage would not result in a significant increase of radionuclide release (e.g., in excess of 10 CFR 100 limits). In addition, please provide a summary of the assessment performed for the circumferential cracks found during 1R1 7 in the original tube-to-tubesheet rolls, tube-to-tubesheet re-roll repairs, and heat affected zones of seal welds to establish their contribution to the calculated 1.87 gpm leakage.