ML043580381
| ML043580381 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/23/2004 |
| From: | Matthews W Dominion Nuclear Connecticut |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 04-140A | |
| Download: ML043580381 (3) | |
Text
Dominion Nuclear Connecticut, Inc.
Mill\\rone Power Station l b p c Fcry Road K,irc:-hrd CT 06385 December 23, 2004 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.:
04-1 40A Docket No.:
50-336 NL&OS/PRW Rev 3 License No.:
DPR-65 DOMINION NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNIT 2 USE OF AN ALTERNATIVE TO ASME CODE SECTION XI FOR INSTALLATION OF MECHANICAL NOZZLE SEAL ASSEMBLIES ON PRESSURIZER HEATER PENETRATION NOZZLES CHANGE TO REQUEST RR-89-35. REVISION 1 In a letter dated June 3, 2004, Dominion Nuclear Connecticut, Inc. (DNC) forwarded relief request RR-89-53, Revision 1, Use of an Alternative to ASME Code Section XI for Installation of Mechanical Nozzle Seal Assemblies (MNSAs) on Pressurizer Heater Penetration Nozzles, to the Nuclear Regulatory Commission (NRC). This relief request addressed continued use of the MNSAs as a permanent alternative. In a conference call on November 18, 2004, the NRC advised DNC that with a commitment to replace the Millstone Power Station Unit 2 (MPS2) pressurizer in the fall of 2006, DNC could extend the use of the MNSAs for an additional cycle and that a permanent relief request was not necessary.
Accordingly, DNC hereby withdraws its request dated June 3, 2004. DNC commits to replace the MPS2 pressurizer during Refueling Outage 2R017 currently scheduled for the fall of 2006. DNC requests that the NRC revise its previous approval and associated safety evaluation dated June 19, 2002, which authorized use of MNSAs at MPS2, to allow use of the MNSAs one additional cycle.
Installation, inspection] and testing of the MNSAs will continue consistent with the previously approved relief request RR-89-35. During plant startup (Mode 3) after initial MNSA installation and during subsequent plant restarts following a refueling outage, the pressurizer heater penetration nozzle MNSAs will be pressure tested and inspected for leakage. To ensure quality of the installation and continued operation with the absence of leakage, a pressure test with VT-2 visual examination will be performed on each of the installed MNSAs with insulation removed. The test will be performed as part of plant restart and will be conducted at normal operating pressure with the test temperature determined in accordance with the MPS2 pressure and temperature limits as stated in the MPS2 Technical Specifications. Additionally, VT-3 exams will be performed to verify general structural and mechanical condition of the MNSAs.
Serial No. 04-140A Docket No. 50-336 Change to Relief Request Page 2 of 3 These examinations are performed in accordance with the 1989 Edition of ASME Section XI under the current third 10-year IS1 program and as such meet the personnel qualification requirements and acceptance criteria of the Code. The VT-2 visual examination also meets the plants boric acid inspection program requirements and will be enhanced to specify that the examination shall include visual access to at least 360Q of bare metal around each MNSA.
In addition to these examinations, the bolting of the MNSAs is subject to inspection as an Examination Category B-G-2 item. Therefore, a VT-1 visual examination is required at least once each inspection interval. This VT-1 visual examination may be performed with the bolting (a) in place under tension; (b) when the connection is disassembled; or (c) when the bolting is removed.
However, later editions of NRC approved ASME Section XI recognized that in order to perform a useful VT-1 visual examination, bolting must be disassembled, and thus only requires this examination when the connection is disassembled.
For purposes of this request, MPS2 proposes to perform the VT-1 visual examination associated with item B-G-2 only if a connection is disassembled.
Finally, one aspect of this VT-1 visual examination that is not covered in the Code requirements is the threaded area of the bolt holes in the base metal of the pressurizer. These bolt holes will also receive a VT-1 visual examination any time the connection is disassembled.
Should you have any questions regarding the above, please contact Mr. Paul R.
Willoughby at (804) 273-3572.
Very truly yours, a&%&
William R. Matthews Senior Vice President - Nuclear Operations
Serial No. 04-140A Docket No. 50-336 Change to Relief Request Page 3 of 3 Commitments contained within this letter:
DNC commits to replace the MPS2 pressurizer during Refueling Outage 2R017 currently scheduled for the fall of 2006.
cc:
U. S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1 41 5 Mr. V. Nerses Senior Project Manager U. S. Nuclear Regulatory Commission One White Flint North 1 1555 Rockville Pike Mail Stop 8C2 Rockville, MD 20852-2738 Mr. S. M. Schneider NRC Senior Resident Inspector Millstone Power Station