ML023360258

Request for Additional Information Re. Bulletin 2002-01

ML023360258
Person / Time
Site:	Arkansas Nuclear
Issue date:	11/04/2002
From:	Office of Nuclear Reactor Regulation
To:
Alexion T W,NRR/DLPM,415-1326
Shared Package
ML023400438	List: ML023360258 ML023360374 ML023360421 ML023360446 ML023360449 ML023440149 NOC-AE-02001368, E-mail Kenneth Taplett to Mohan Thadani, Replacement Page NOC-AE-02001368
References
BL-02-001
Download: ML023360258 (1)

Text

Request for Additional Information Related to Bulletin 2002-01 Arkansas Nuclear One, Unit 1 (ANO-1)

1. Provide detailed drawings and dimensions of the vessel bottom (including the vessel skirt, insulation, etc.) showing the instrumentation nozzles; include on these drawings the boric acid deposits (e.g., staining) based on information obtained from your videotapes. Show the nozzles in the vicinity of nozzle 30 down to nozzle 1, and in the vicinity of nozzle 15 down to nozzle 1.

2. Explain your best efforts to locate the source of the boric acid deposits. Address the feasibility of performing additional inspections of the annulus between the vessel/support skirt and the vertical insulation or from the under vessel area to provide further evidence of the path of borated water through the 2 inch support skirt openings.

3. Characterize the boric acid deposits.

4. Describe what you see in the space between the vessel base metal and the outside diameter of the instrumentation nozzles.

5. Provide the Owners Group's susceptibility report for the instrumentation nozzles and welds, as installed.

6. Describe the previous boric acid overfill events and corrective actions taken in response to these events.

7. Explain how identification of these boric acid deposits and any corrective actions comport with your boric acid control program and the ASME Code requirements.

Discuss any program or procedure changes you plan to undertake as a result of this experience.

8. Summarize recommendations received from Framatome for inspection of the incore instrumentation nozzles and your disposition of these recommendations, and provide the basis for any recommendation not followed.