ML20030E063
| ML20030E063 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 09/15/1981 |
| From: | Litton F Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20030E021 | List: |
| References | |
| NUDOCS 8109170372 | |
| Download: ML20030E063 (5) | |
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9/lS/81 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of
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PENNSYLVANIA POWER & LIGHT COMPANf )
Docket Nos.
50-387 ALLEGHENY ELECTRIC COOPERATIVE, INC.)
50-388
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(Susouehanna Steam Electric Station,)
Units 1 and 2)
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NRC STAFF TESTIMONY OF FELIX B. LITTON REGARDING CRACKING IN BWR CORE SFRAY N0ZZLES (Contention 7c)
Q.1.
Please state your name and position with the NRC.
A.1.
My name is Felix B. Litton and I am a Senior Materials Engineer, Materials Engineering Branch, Division of Engineering, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Comission.
Q.2.
Have you prepared a statement of professional qualifications?
A.2.
Yes. A copy is attached to this testimony.
Q.3.
Please state the scope of your responsibilities for the review of. the coerating license application for the Susquehanna facili ty.
A.3.
I am responsible for the review and evaluation of those sections of the Applicants Final Safety Analysis Report for which the itaterials Application Section of the Materials 8109170372 810915 PDR ADOCK 05000387 NT PDR
I Engineering Branch has primary review responsibility. This responsibility includes a review of the materials used for the construction of the reactor coolant pressure boundary and methods for inspection to, preserve component intergrity.
Q.4.
What is the purpose of your testimony?
A.4.
The purpose of my testimony is to address Contention 7c which states:
The Nuclear Steam Supply Systems of Susquehanna 1 and 2 contain numerous generic design deficiencies, same of which may never be resolvable, and which, when reviewed together, render a picture of an unsafe nuclear installation which may never be safe enough to operate. Specifically:
BWR core spray nozzles occasionally crack, a problem which reduces their effectiveness.
Q.5.
Do you agree that BWR core spray nozzlbs occasionally crack?
A.5.
No, I disagree.
Q.6.
What is the basis for your disagreement?
A.6.
There have been no incidents of BNR core spray nozzle cracking reported to the NRC Staff.
Q.7.
But have there been incidents of cracking in core spray spargers, reactor vessel nozzle safe-ends, control rod drive return line nozzles, and feedwater system nozzles at operating BWR facilities?
A.7.
Yes.
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3 Q.8.
Has the cause of the cracking in those BWR components and systems been determined?
A.8.
Yes. The cracking in core spray spargers and reactor vossel nozzle safe-ends was attributed to intergranular stress corrosion of the sensitized materials in those conponents.
The cracking in control rod drive return line nozzles and feedwater system nozzles was attributed to thermal fatigue.
Q.9.
Has the NRC Staff established guidance for eliminating or reducing the susceptibility to cracking of the BWR components and systems listed in Q7 above?
A.9.
Yes. UUREG-0313, Revision 1, ' Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure i
Boundary Piping," dated July 1980, sets forth methods acceptable to the NRC Staff for preventing or reducing the susceptibility to intergranular stress corrosion cracking of SWR components and systems. NUREG-0619. "BNR Feedwater Nozzle and Control Rod Drive Return Line Nozzle Cracking,"
dated November 1980, sets forth methods acceptable to the NRC Staff for eliminating concerns about cracking of nozzles in the control rod drive return lines and the feedwater system.
Q.10 What actions have the Applicants taken in response to the Y aff's guidance?
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. A.10.
The Applicants have replaced all the material in the core sprey system which could be susceptible to intergranular stress corrosion cracking with material thec is not susceptible as recanmended in Section III af NUREG-0313, Revision 1.
(See Section 5.2.3.2. of Supplement 2 to the SER). Materials that could be susceptible to intergranular stress corrosion cracking have not been used in the reactor vessel nozzle safe-end: of the Susquehanna units. Control rod drive return lines have been eliminated from the Susquehanna design, and the feedwater system has been redesigned. The latter two actions were teken in response to
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the recommendations of NUREG-0619.
Q.11.
Do you believe that the actions taken or to be taken by the Applicants to eliminate cracking in BWR components and systems of the types discussed above in Q7 will assure that such cracking will not endanger the health and safety of the public?
A.11.
Yes, because the Applicant's have followed the guidance set forth in NbREG-0313, Revision 1 and NUREG-0619 in resolving cracking problem:.
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PROFESSIONAL QUALIFICATIONS FELIX 8. LITTON I am a Senior Materials Engineer in the Materials Engineering Branch of the Office of Nuclear Reactor Regulation, Nuclear Rc.;ulatory Commission.
I am attached to the lhterials Integrity tection and am responsible for the review and evaluation of materials and processes used 'in the construction and operation of ccmpen, cats.in the nuclear pcuer industry.
My education consists of a B. S. (1936) and M. S. (1937) degree in Physical Chemistry from Virginia Polytechnic Institute, Blacksburg, Va.
I have coupleted additional study in Material Science (1967) at the Uriversity of New Mexico and have taken special courses in Fracture Mechanics (1977) ut ' George Wa.shington University.
Prior to joining the Nuclear Regulatory Commission, my experience consists of metallurgical research related to the preparation, fabrication and alloy fonnation of new structural materials for nuclear, advanced aircraft and high temperature application.
I have published in technical journals on the environmental Sehavior, thermodynamic stability and mechanical properties of uranium, plutonium, vanadium, zirconium, titanium, hafnium and silicon and their alloys. My experience in ferrous metallurgy relates to the cause of failure in service.
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