RBG-30883, Forwards Proprietary, Evaluation of Indication in River Bend Feedwater Nozzle to Safe End Weld, Per Inservice Insp. Util Will Take Listed Actions.Evaluation of Radiographs from Const Inps Reviewed.Rept Withheld (Ref 10CFR2.790)

Forwards Proprietary, Evaluation of Indication in River Bend Feedwater Nozzle to Safe End Weld, Per Inservice Insp. Util Will Take Listed Actions.Evaluation of Radiographs from Const Inps Reviewed.Rept Withheld (Ref 10CFR2.790)

ML20247A942
Person / Time
Site:	River Bend
Issue date:	05/15/1989
From:	Booker J GULF STATES UTILITIES CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML19302D902	List: RBG-30883, Forwards Proprietary, Evaluation of Indication in River Bend Feedwater Nozzle to Safe End Weld, Per Inservice Insp. Util Will Take Listed Actions.Evaluation of Radiographs from Const Inps Reviewed.Rept Withheld (Ref 10CFR2.790)
References
GL-88-01, GL-88-1, RBG-30883, NUDOCS 8905230334
Download: ML20247A942 (8)

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GULF STATES UTILITIES COMPANY '

RIVER BEND STATION POST OFFICE BOX 220 $T FRANCISVILLE, L0utSIAN A 70775 ARE A CODE t,04 635-6094 '346 8661 May 15,1989 RBG- 30883 File Code G9.5 U. S. Nuclear Regulatory Commission i Document Control Desk Washington, D.C. 20555

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Gentlemen:

River Bend Station - Unit 1 Docket No. 50-458 During the' current refueling' outage at River Bend Station, an Inservice Inspection (ISI) was performed in accordance with ASME. Code Section XI and Generic Letter 88-01. The augmented inspection identified an indication in the N4-A feedwater inlet nozzle to safe end weld. A circumferential indication, as shown on Figure 1, was identified on the safe end side of the weld,.in the buttered area. The indication was detected and sized to be approximately six inches long, with a maximum depth of approximately 0.2 inches and an-average depth of 0.16 inches. Based on the technologies applied, as listed- in Table 1, the evaluation of the indication displayed branching affects and had measurable depth. However, the examination.was not conclusive with respect to the actual presence of IGSCC.

Although the presence of an IGSCC crack could not be definitively confirmed, a crack growth evaluation was performed assuming that the observed indication was due to an active IGSCC crack. The predicted crack size at the end of the next fuel cycle was determined assuming upper bounding crack growth rate and compared with the ASME Code allowable flaw size. The results of the crack growth and fracture mechanics assessment are described in Attachment 1.

Gulf States Utilities (GSU) has determined that operation for the next cycle

.is acceptable in the current condition. This is based on an evaluation of the condition, including an assessment of growth rates and fracture mechanics provided by General Electric (GE). In addition to this evaluation, GSU will take the following additional actions:

1. The subject feedwater nozzle weld will be re-examined during the mid-cycle outage planned for cycle 3. This outage is currently scheduled for approximately nine months after start-up from the current refueling outage. The results of the mid-cycle examination and evaluation will be provided to the NRC along with a description of any further corrective actions.

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NRC Page 2 Z. The subject feedwater nozzle weld will also be re-examined during the third refueling outage per the requirements of Generic Letter 88-01. This will allow further determination and verification of growth of the indication, if any.

Additional evaluations of the area of interest were performed as follows:

An evaluation of the original radiographic from construction inspections were reviewed and enhanced to further define the area of int' oest. Review of the unenhanced radiographs produced no rejectable or clear '.;dications. This supports the original interpretation done before the vessel was put into service. The enhanced version of the radiographs produced no conclusive indications to support the ultrasonic results obtained during this refueling outage Several small indications which are representative of fusion and solidification flaws were noted after enhancement; however, these flaws are not discernable on the original film. Radiographs of the remaining nozzles were also reviewed in the original and enhanced conditions with comparable results.

An evaluation of the construction ultrasonic reports from Chicago Bridge and Iron (CB&I) and the PSI automated reports from Rockwell International did not indicate any relevant indications in the area of interest. The evaluation of the ultrasonic reports from Ebasco performed by EPRI qualified inspectors confirmed the indication as found during this outage. The remainder of feedwater nozzles (N-4) were examined based on response to Generic Letter 88-01 by EPRI qualified inspectors with no relevant indication being detected.

In accordance with the reporting requirements of Generic Letter 88-01, this evaluation of the subject weld indication and the assessment of growth rate is provided for your review and approval. Because the unit is scheduled for restart by the end of May,1989, your prompt attention to this submittal is requested.

The attached report contains information that is proprietary to GE. GSU requests that the Attachment be withheld from public disclosure in accordance with 10CFR2.790(a)(4). In accordance with 10CFR2.790(b)(1), an affidavit supporting this request is attached.

If you need any additional information, p hase contact Mr. David N. Lorfing at (504) 381-4157.

Sincerely,

.fa buYf J. E. Booker Manager-River Bend Oversight River Bend Nuclear Group JEB/LAE/MFS/DNL/ch Attachments

.cc: U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive. Suite 1000 Arlington, TX 76011 NRC Resident Inspector P. O. Box 1051 St. Francisville, LA~70775-

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1. * 'O40DS EMPLOYED FOR DETECTION SIL - 455 A) 45' Refracted Longitudinal Wave B). 60* Refracted Longitudinal Wave EPRI Technique.for IGSCC Detection-

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C)~ 45' Shear Wave Exams . performed by personnel qualified to Generic Letter 88-01 and NUREG 0313.Rev 2. Final.

'2. METHODS EMPLOYED'FOR DISCRIMINATION A) 45' R/L E. Same technique employed during the phase and 45' Shear B) WSY - 70 or ID Creeping Wave

.These~ employed or characterization' (e.i.: flaw, Echco Dynamics & signal.)

Performed'by independent examiner / evaluation not involved during the initial detection examination.

3. METHODS EMPLOYED FOR SIZING A) WSY - 70 or ID Creeper Wave

. Performed for quantitative sizing.

B) AAT (52* Utilizing Shear Wave highly damped.

C). RATT (Utilizing 52* Shear Wave highly damped.

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CENERAL ELECTRIC C0MPANY AFFIDAVI'{

I, Rudolph Villa, being duly sworn, depose and state as follows:

1. I am Manager, Consulting Services, General Electric Company, and have been delegated the function of reviewing the information described in paragraph 2 which is sought to be withheld and have been authorized to apply for its withholding.

2. The information sought to be withheld is contained in a report to the NRC entitled, " Evaluation of the Indication in the River Bend Feedwater Nozzle to Safe End Weld," dated May 12, 1989, and it discussed observed cracking of the weld. A copy of the report is attached.

3. In designating material as proprietary, General Electric utilizes the definition of proprietary information and trade secrets set forth in the American Law Institute's Restatement of Torts, Section 757. This definition provides:

"A trade secret may consist of any formula, pattern, device or compilation of information which is used in one's business and which gives him an opportunity to obtain an advantage over competitors who do not know or use it.... A substantial element of secrecy must exist, so that, except by the use of improper means, there would be difficulty in acquiring information. . . . Some factors to be considered in determining whether given information is one's trade secret are: (1) the extent to which the information is known outside of his business; (2) the extent to which it is known by employees and others involved in his business; (3) the extent of measures taken I

by him to guard the secrecy of the information; (4) the value of the information to him and to his competitors; (5) the amount of effort or money expanded by him in developing the information; (6) the ease or difficulty i

with the which the information could be properly acquired or duplicated by others."

4. Some examples of categories of information which fit into the definition of proprietary information are:

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a. Information that discloses a process, method or apparatus where prevention of its use by General Electric's competitors without license from General Electric constitutes a competitive econom-ic advantage over other companies; a _ _ __ _ __ i

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b. Information consisting of supporting data and analyses, includ-ing test data, rel.1tive to a process, method or apparatus, the application of which provide a competitive economic advantage, e.g., by optimization or improved marketability;

c. Information which if used by a competitor, would reduce his

- expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality or licensing of a similar product;

d. Information which reveals cost or price information, production capacities, budget levels or commercial strategies of General Electric, its customers or suppliers;

e. Information which reveals aspects of past, present or future General Electric customer-funded development plans and programs of potential commercial value to General Electric;

f. Information which discloses patentable subject matter for which it may be desirable to obtain patent protection;

g. Information which General Electric must treat as proprietary according to agreements with other parties.

5. Initial approval of proprietary treatment of a document is typically made by the Subsection manager of the originating component, the person who is most likely to be acquainted with the value and sensitivity of the information in relation to industry knowledge.

Access to such documents within the Gompany is limited on a "need to know" basis and such documents are clearly identified as proprie-tary.

6. The procedure for approval of external release of such a document typically requires review by the Subsection Manager, Project Manag-er, Principal Scientist or other equivalent authority, by the Subsection Manager of the cognizant Marketing function (or delegate) and by the Legal Operation for technical content, competitive effect and determination of the accuracy of the proprietary designation in accordance with the standards enumerated above. Disclosures outside General Electric are generally limited to regulatory bodies, custom-ers and potential customers and their agents, suppliers and licensees then only with appropriate protection by applicable regulatory provisions or proprietary agreements.

7. The document mentioned in paragraph 2 above has been evaluated in accordance with the above criteria and procedures and has been found to contain information which is proprietary and which is customarily held in confidence by General Electric.

8. The information to the best of my knowledge and belief has consis-tently been held in confidence by the General Electric Company, no public disclosure has been made, and it is not available in public sources. All disclosures to third parties have been made pursuant to regulatory provisions of proprietary agreements which provide for maintenance of the information in confidence.

9. Public disclosure of the information sought to be withheld is'likely to cause substantial harm to the competitive position of the General Electric Company and deprive or reduce the availability of profit making opportunities because it would provide other parties, includ-ing competitors, with valuable information.

STATE OF CALIFORNIA

) 88 COUNTY OF SANTA CLARA )

Rudolph Villa, being duly sworn, deposes and says:

That he has read the foregoing affidavit and the matters stated therein are true and correct to the best of his knowledge, information, and belief.

Executed at San Jose, California, this /2 ay of // b , 19/7.

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/hWYA Rudolph Vil%

General Electric Company M 1 Subscribed and sworn before me thisf,, day of /NA4 19 8_f_.

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i NOTARY PUBLIC, STATE OF CALIFORNIA OFFICIAL SEAL MARY L KENDALL Notary Publio-Callomia i *- SANTA CLARA COUNTY My Comm. Exp. Mar. 26.1993

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