ML043350009

Core Spray Flaw Evaluation

ML043350009
Person / Time
Site:	Dresden
Issue date:	01/18/2005
From:	Banerjee M NRC/NRR/DLPM/LPD3
To:	Suh G NRC/NRR/DLPM/LPD3
Banerjee M, NRR/ADPT, 415-2277
References
TAC M98941, TAC MA1673
Download: ML043350009 (3)

Text

January 18, 2005 MEMORANDUM TO: Gene Suh, Chief, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation FROM: Maitri Banerjee, Senior Project Manager, Section 2 /RA/

Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation

SUBJECT:

DRESDEN UNITS 2 AND 3 - CORE SPRAY FLAW EVALUATION (TAC NOS. MA1673 AND M98941)

By letters dated April 11, 1998, and June 5, 1997, the licensee submitted core spray flaw evaluations for Dresden Unit 2 and Unit 3 respectively. The Nuclear Regulatory Commission (NRC) staff opened TAC numbers MA1673 (Unit 2) and M98941 (Unit 3) for review of the flaw evaluation submittals.

The flaw evaluation reports submitted by the licensee were to meet the requirements set forth in Bulletin 80-13, Cracking in Core Spray Spargers, which required the licensee to perform a visual inspection of the Core Spray Spargers and the segment of piping between the inlet nozzle and the vessel shroud at each refueling outage until further notice and submit a written report of the results of the examinations including any corrective measures. The licensee also submitted a core spray piping inspection plan for both Unit 2 and Unit 3. This inspection plan proposed the use of Boiling Water Reactor Vessel and Internals Project (BWRVIP)-18, BWR Core Spray Internals Inspection and Flaw Evaluation Guidelines, which had yet to be approved by the NRC staff. The proposed inspection plan was approved pending NRC staff approval of BWRVIP-18.

Subsequently, BWRVIP-18 was approved and the licensee has verified compliance in their inservice inspection summary reports dated July 16, 1998, January 25, 2000, and February 5, 2002, for Unit 2, and May 20, 1999, December 29, 2000, and January 24, 2003, for Unit 3. The owner activity reports dated February 9, and December 1, 2004, provided results of the core spray pipe inspection during the D2R18 refueling outage. The reports indicate that the licensee has been monitoring and evaluating the identified flaws following the guidelines of BWRVIP-18.

The licensee also verbally verified compliance with BWRVIP-18 to the NRC staff on a phone call conducted August 5, 2004. Based on the licensees commitment to follow the BWRVIP-18 guidelines for inspection, flaw evaluation and monitoring of core spray line inside the vessel, no further review of the April 11, 1998 and June 5, 1997 letters is necessary, and the TAC Nos.

MA1673 and M98941 may be closed.

G. Suh Additionally, during the D3R18 refueling outage in November 2004, the licensee replaced the lower (vertical) section of all four degraded core spray piping inside the reactor vessel annulus area with intergranular stress-corrosion cracking resistant fittings, and eliminated P4c, P4d, P5, P6, P7, P8a, P8b and P9 welds with bolted joints. Two new sparger clamps eliminated three welds in the sparger T-box and sparger pipes. The licensee believes this partial replacement renders any future weld cracking in the remaining core spray pipe section to be manageable.

The NRC will continue to monitor the ISI reports for core spray pipe inspection results.

Therefore, TAC numbers MA1673 and M98941 are closed. Closing of these TAC Nos. does not imply NRC acceptance of the core spray pipe replacement modification at Dresden Unit 3.

Docket Nos. 50-237 and 50-249

ML043350009 OFFICE PDIII-2/PM PDIII-1/PM PDIII-2/LA EMCB-B/SC PDIII-2/SC NAME MBanerjee JStang PCoates TChan GSuh DATE 01/12/05 01/ 13 /05 01/ 13 /05 01/ 12 /05 01/ 18 /05