L-MT-06-083, Results of 2005 BWR Core Shroud Inspection
| ML063630244 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 12/28/2006 |
| From: | Conway J Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2010-0209, L-MT-06-083 | |
| Download: ML063630244 (2) | |
Text
December 28,2006 L-MT-06-083 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Monticello Nuclear Generating Plant Docket 50-263 License No. DPR-22 Results of Monticello Nuclear Generating Plant 2005 BWR Core Shroud Inspection The Nuclear Management Company, LLC (NMC) is providing the following information to fulfill the reporting requirements associated with EPRl document BWRVIP-76 "BWR Core Shroud lnspection and Flaw Evaluation" resulting from the 2005 shroud inspection at the Monticello Nuclear Generating Plant (MNGP). The reporting requirements are contained in section 4 and table C-9 of BWRVIP-76. Submittal of plant specific analysis is required when percent indication is greater than or equal to 10% of the covered area and fluence for the weld exceeds 5x10~' n/cm2. Furthermore, when plant specific analysis is performed the results will be submitted to the Nuclear Regulatory Commission. This letter is being submitted to satisfy the above requirements.
Below is a table of weld locations and results from the ultra-sonic examinations. The allowable years of service were determined using Limit Load or LEFM methodology.
Application of a limit load and LEFM were determined using Appendix D of BWRVIP-76.
2807 West County Road 75 Monticello, Minnesota 55362-9637 Telephone: 763.295.5151 Fax: 763.295.1454 Weld H I H2 H3 H4 (Upper)
H4 (Lower)
H5 H6 H7
% Indication 16.21 %
6.02%
27.19%
8.33%
5.02%
0.50%
2.52%
0.00%
Allowable Years of Service Per Appendix D of BWRVIP-76 10 10 10 10 10 10 10 10 Fluence n/cm2 (bounding Value) 4.7E+18 6.27E+20 6.42E+20 1.99E+21 1.99E+21 7.90E+17
<7.90E+17
<7.90E+17 Limit Load or LEFM analysis Limit Load LEFM LEFM LEFM LEFM Limit Load Limit Load Limit Load
% coverage 75.51 %
59.26%
71.56%
68.46%
68.46%
68.46%
68.88%
68.88%
USNRC Page 2 of 2 The flaw evaluation analysis supporting the results is considered Electric Power Research Institute (EPRI) proprietary information and therefore cannot be transmitted.
The analysis will be available for review at the Monticello facility and will be available at the request of your staff.
Summarv of Commitments This letter contains no new commitments and no revisions to existing commitments.
- x. P'..LULt$
John T. Conway Site Vice President, Monticello Nuclear Generating Plant Nuclear Management Company, LLC cc:
Administrator, Region Ill, USNRC Project Manager, Monticello, USNRC Resident Inspector, Monticello, USNRC