ML060950629

GALL AMP: XI.M33, Selective Leaching of Materials (Audit Worksheet GALL Report AMP)

ML060950629
Person / Time
Site:	Vermont Yankee
Issue date:	03/22/2006
From:	Morgan M NRC/NRR/ADRO/DLR/RLRC
To:	Office of Nuclear Reactor Regulation
morgan M NRR/NRC/DLR/RLRC, 415-2232
Shared Package
ML060950189	List: ML060950195 ML060950215 ML060950218 ML060950220 ML060950224 ML060950235 ML060950250 ML060950258 ML060950262 ML060950269 ML060950271 ML060950277 ML060950279 ML060950284 ML060950290 ML060950301 ML060950311 ML060950323 ML060950328 ML060950331 ML060950347 ML060950351 ML060950356 ML060950364 ML060950370 ML060950372 ML060950375 ML060950540 ML060950549 ML060950559 ML060950567 ML060950570 ML060950573 ML060950579 ML060950582 ML060950587 ML060950596 ML060950606 ML060950610 ML060950620 ML060950624 ML060950629 ML060950632 ML060950634 ML060950637 ML060950645 ML061000078 ML061000090 ML061000096 ML061000101 ... further results
References
%dam200611, TAC MC9668
Download: ML060950629 (5)

Text

AUDIT WORKSHEET GALL REPORT AMP PLANT: ______________________________

LRA AMP: __________________________ REVIEWER: ______________________

GALL AMP: XI.M33, Selective Leaching of Materials DATE: __________________________

Program Auditable GALL Criteria Documentation of Audit Finding Element Program A. The program for selective leaching of materials ensures the Consistent with GALL AMP: Yes No Description integrity of the components made of cast iron, bronze, brass, Document(s) used to confirm Criteria:

and other alloys exposed to a raw water, brackish water, treated water, or groundwater environment that may lead to selective leaching of one of the metal components. The aging management program (AMP) includes a one-time visual Comment:

inspection and hardness measurement of selected components that may be susceptible to selective leaching to determine whether loss of materials due to selective leaching is occurring, and whether the process will affect the ability of the components to perform their intended function for the period of extended operation.

1. Scope of A. This AMP determines the acceptability of the components Consistent with GALL AMP: Yes No Program that may be susceptible to selective leaching and assesses their Document(s) used to confirm Criteria:

ability to perform the intended function during the period of extended operation. These components include piping, valve bodies and bonnets, pump casings, and heat exchanger components. The materials of construction for these Comment:

components may include cast iron, brass, bronze, or aluminum-bronze. These components may be exposed to a raw water, treated water, or groundwater environment. The AMP includes a one-time visual inspection and hardness measurement of a selected set of sample components to determine whether loss of material due to selective leaching is not occurring for the XI.M33 Selective Leaching of Materials 1

Program Auditable GALL Criteria Documentation of Audit Finding Element period of extended operation.

The selective leaching process involves the preferential removal of one of the alloying elements from the material, which leads to the enrichment of the remaining alloying elements.

Dezincification (loss of zinc from brass) and graphitization (removal of iron from cast iron) are examples of such a process.

Susceptible materials, high temperatures, stagnant-flow conditions, and corrosive environment such as acidic solutions, for example, for brasses with high zinc content, and dissolved oxygen, are conducive to selective leaching.

2. Preventive A. The one-time visual inspection and hardness measurement is Consistent with GALL AMP: Yes No Actions an inspection/verification program; thus, there is no preventive Document(s) used to confirm Criteria:

action. However, it is noted that monitoring of water chemistry to control pH and concentration of corrosive contaminants, and treatment with hydrazine to minimize dissolved oxygen in water are effective in reducing selective leaching. Comment:

3. Parameters A. The visual inspection and hardness measurement is to be a Consistent with GALL AMP: Yes No Monitored/ one-time inspection. Because selective leaching is a slow acting Document(s) used to confirm Criteria:

Inspected corrosion process, this measurement is performed just before the beginning of the license renewal period. Follow-up of unacceptable inspection findings includes expansion of the inspection sample size and location. Comment:

4. Detection of A. The one-time visual inspection and hardness measurement Consistent with GALL AMP: Yes No Aging Effects includes close examination of a select set of components to Document(s) used to confirm Criteria:

determine whether selective leaching has occurred and whether the resulting loss of strength and/or material will affect the intended functions of these components during the period of extended operation. Selective leaching generally does not Comment:

cause changes in dimensions and is difficult to detect. However, in certain brasses it causes plug-type dezincification, which can be detected by visual inspection. One acceptable procedure is to visually inspect the susceptible components closely and conduct Brinell Hardness testing on the inside surfaces of the selected set of components to determine if selective leaching XI.M33 Selective Leaching of Materials 2

Program Auditable GALL Criteria Documentation of Audit Finding Element has occurred. If it is occurring, an engineering evaluation is initiated to determine acceptability of the affected components for further service.

5. Monitoring A. There is no monitoring and trending for the one-time visual Consistent with GALL AMP: Yes No and Trending inspection and hardness measurement. Document(s) used to confirm Criteria:

Comment:

6. Acceptance A. Identification of selective leaching will define the need for Consistent with GALL AMP: Yes No Criteria further engineering evaluation before the affected components Document(s) used to confirm Criteria:

can be qualified for further service. If necessary, the evaluation will include a root cause analysis.

Comment:

7. Corrective A. Evaluations are performed for test or inspection results that Consistent with GALL AMP: Yes No Actions do not satisfy established acceptance criteria. The corrective Document(s) used to confirm Criteria:

actions program ensures that conditions adverse to quality are promptly corrected. If the deficiency is assessed to be significantly adverse to quality, the cause of the condition is determined and an action plan is developed to preclude Comment:

repetition. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the corrective actions.

8. A. Site quality assurance (QA) procedures, review and approval Consistent with GALL AMP: Yes No Confirmation processes, and administrative controls are implemented in Document(s) used to confirm Criteria:

Process accordance with the requirements of 10 CFR Part 50, Appendix B. As discussed in the appendix to this report, the staff finds the requirements of 10 CFR Part 50, Appendix B, acceptable to address the confirmation process and administrative controls. Comment:

9. A. See Item 8, above. Consistent with GALL AMP: Yes No Administrative Document(s) used to confirm Criteria:

Controls XI.M33 Selective Leaching of Materials 3

Program Auditable GALL Criteria Documentation of Audit Finding Element Comment:

10. Operating A. One-time inspection is a new program to be applied by the Consistent with GALL AMP: Yes No Experience applicant. The elements that comprise these inspections (e.g., Document(s) used to confirm Criteria:

the scope of the inspections and inspection techniques) are consistent with industry practice and staff expectations.

Comment:

XI.M33 Selective Leaching of Materials 4

EXCEPTIONS Item Program Elements LRA Exception Description Basis for Accepting Exception Documents Reviewed Number (Identifier, Para.# and/or Page #)

1.

2.

ENHANCEMENTS Item Program Elements LRA Enhancement Description Basis for Accepting Enhancement Documents Reviewed Number (Identifier, Para.# and/or Page #)

1.

2.

DOCUMENT REVIEWED DURING AUDIT Document Number Identifier (number) Title Revision and/or Date 1.

2.

3.

4.

XI.M33 Selective Leaching of Materials 5