ML103480682

Request for Additional Information Email, Request for Alternative ANO1-R&R-013, Fourth 10-Year Inservice Inspection Interval, Repairs to the Pressurizer Instrumentation Penetrations

ML103480682
Person / Time
Site:	Arkansas Nuclear
Issue date:	12/14/2010
From:	Kalyanam N Plant Licensing Branch IV
To:	Clark R Entergy Operations
Kalyanam N, NRR/DORL/LPL4, 415-1480
References
TAC ME3701
Download: ML103480682 (2)

Text

From: Kalyanam, Kaly Sent: Tuesday, December 14, 2010 10:53 AM To: CLARK, ROBERT W Cc: Lent, Susan; Burkhardt, Janet

Subject:

RAI for ME3701

Bob, I am formalizing the Request for Additional Information sent on Entergys Request for Alternative ANO1-R&R-013, Fourth 10-Year Inservice Inspection Interval, Repairs to the Pressurizer Instrumentation Penetrations.

Thanks.

N. Kalyanam PM, Arkansas Nuclear One, Unit 1 and 2 and Waterford 3.

The SUNSI information as follows:

Plant: Arkansas Nuclear One, Unit 1 Docket No.: 50-313

Subject:

RAI on Requests for Alternative ANO1-R&R-013 TAC Nos.: ME3701, SUNSI Review Done: Yes. Publicly Available, Normal Release, Non-sensitive, From: N. Kalyanam To: Robert Clark REQUEST FOR ADDITIONAL INFORMATION RELIEF REQUEST ANO1-R&R-013 REPAIRS TO THE PRESSUIRZER INSTRUMENTATION PENETRATIONS ARKANSAS NUCLEAR ONE, UNIT 1 ENTERGY OPERATIONS, INC DOCKET NO 50-313 By letter dated April 5, 2010, Entergy Operations, Inc., requests approval of proposed alternatives in Relief Request ANO1-R&R-013 to the requirements associated with repair of pressurizer instrumentation penetrations at the Arkansas Nuclear One, Unit 1 (ANO-1). To complete its review, the staff requests the following additional information.

Relief Request ANO1-R&R-013

1. Page 1. (1) Discuss why there are three different editions of the ASME Code,Section III, that are applicable to the ANO-1 pressurizer. (1) Clarify whether the affected component, RC-1001 A/B, identified under Section 1 of the relief request is the only instrument nozzle or a group

of instrument nozzles that need to be repaired. (2) Confirm that the affected nozzle is an ASME Code Class 1 component.

2. Page 2. Section 4 states that the original partial penetration attachment weld and a remnant of the original nozzle will remain in place. Figure 1 of the relief request shows that a weld pad is installed at the outside surface of the pressurizer shell. Clarify the location of the original partial penetration attachment weld using the diagram in Figure 1 of the relief request.

3. Page 3. Section 5(A) discusses a flaw evaluation for a postulated flaw in the J-groove weld and nozzle. Section 5(B) discusses a flaw evaluation for a postulated flaw in penetration RC-1001 A/B. (1) Discuss the difference between the flaw evaluations in Sections 5(A) and 5(B).

(2) Discuss whether a postulated flaw is assumed to propagate from the J-groove weld or the nozzle into the pressurizer shell wall and that the flaw in the pressurizer wall is demonstrated to be within the allowable flaw size of the pressurizer shell. (3) Submit the flaw evaluations.

4. Page 4, second paragraph. The licensee states that the Alloy 690 nozzle will be attached to the new weld pad with a partial penetration weld using a non-temper bead manual welding technique. Discuss the non-temper bead welding process in detail, e.g., which ASME Code this welding procedure is qualified to, the filler weld material, and the welding process.

5. Page 4, Item (2), states that a surface and ultrasonic examination will be used to inspect the base metal before application of the weld pad. (1) Provide the exact surface area and volume that will be inspected (use a diagram similar to Figure 1 in the relief request to indicate the examination surface area and volume). (2) Discuss the qualification of the ultrasonic examination (reference the appropriate ASME Code section and subsections).

6. Page 4, Item (3) states that a weld pad will be installed on the outside surface of the pressurizer. (1) Clarify whether the weld pad is a metal plate that is welded to the outside surface of the pressurizer or a pad that is fabricated by depositing weld layers at the penetration on the outside surface of the pressurizer. (2) Provide the dimensions (length and width) of the weld pad. (3) Discuss the post-weld inspection of the weld pad and associated welding, including acceptance criteria and qualification for the ultrasonic examination.

7. Page 4, Item (6), states that the new partial penetration attachment weld is examined in accordance with the Construction Code and includes a progressive penetrate [sic] test (PT) examination. (1) Discuss the details of the post-weld examination, such as the acceptance criteria for potential fabrication defects. (2) Discuss whether an ultrasonic examination will be performed on the new partial penetration attachment weld. If not, provide justification.

8. Discuss whether a gap or crevice exists between the end of the replacement (new) nozzle and the end of the existing nozzle inside the penetration. If a gap or crevice exists, discuss the potential for corrosion in that region of the penetration.

9. Discuss the inservice inspection of the repaired nozzle (e.g., inspection frequency, method, and acceptance criteria).

10. Discuss whether all nozzle penetrations at the bottom of the pressurizer shell have been visually examined in light of the degraded instrumentation nozzle.

Flaw Evaluations

11. The licensee submitted three flaw evaluations, ANO-34Q-326, Revision 1, ANO-43Q-301, Revision 2, and ANO-34Q-330, Revision 0. The staff noted that these evaluations were performed in December 2006 and March 2007. These evaluations state that the analyses are applicable to two upper level sensing nozzles (no existing pad), two lower level sensing nozzles, one sampling nozzle, and one modified level sensing nozzle with thermowell replacement.

However, these evaluations do not provide the dimension (wall thickness and diameter) of the nozzles being analyzed. (1) Discuss whether the three flaw evaluations are applicable to the instrumentation nozzle, RC-1001 A/B, in Relief Request ANO1-RR-013. (2) Provide the nozzle sizes (wall thickness and diameter) that were analyzed.

12. (1) Figure 1 in ANO-34Q-326, Revision 1, shows three postulated flaws No. 1, 2 and 3 for the clad/vessel interface location. Discuss the locations of the crack tip of these flaws (e.g., is the crack tip located at the J-groove weld and clad interface, clad and vessel interface, or x distance inside the pressurizer shell wall). (2) Confirm that the three postulated flaws in the penetration bore location are located in the pressurizer shell wall along the axial direction of the penetration bore. (3) Confirm that only axial flaws were postulated for the penetration bore location and clad/vessel interface location. (4) Discuss why circumferential flaws were not postulated in these locations. (5) Confirm that the flaw sizes postulated are consistent with the dimensions of the instrumentation nozzle RC-1001 A/B. (6) Provide the length of the J-groove weld in the circumferential (along the circumference of the pressurizer) and axial (along the nozzle axial) direction (

Reference:

Figure 1 in ANO-34Q-326, Revision 1).

13. ANO-43Q-301, Revision 2, Table 1, shows stress intensity factor summary. (1) Explain why the Ktotal for the penetration bore location is progressively lower from Flaw No. 1 to Flaw No.

3, whereas, the Ktotal for the clad/vessel interface location is progressively higher from Flaw No.

1 to Flaw No.3. (2) Explain why the KIt (stress intensity factor due to thermal and residual stresses) for the penetration bore location is gradually lower as the flaw size increases.

14. Explain why the flaw sizes for the clad/vessel location in Table 1 of ANO-43Q-301, Revision 2, and in Table 2 of ANO-34Q-330, Revision 0, are not the same as the flaw sizes for the clad/vessel location in Figure 1 of ANO-34Q-326, Revision 1.

15. In the flaw evaluations, the transient of cooldown with insurge was included in loading.

However, the staff did not see a discussion of the out-surge transient. Discuss whether the out-surge transient was included in the analysis. If not, provide justification.

16. Discuss whether seismic loads were considered in the flaw evaluations.