ML070650467
| ML070650467 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 02/26/2007 |
| From: | Morris J Duke Energy Carolinas, Duke Power Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML070650467 (4) | |
Text
'ýýDuke Energyo JAMES R. MORRIS Vice President Catawba Nuclear Station 4800 Concord Rd. I CNOIVP York, SC 29745-9635 803 831 4251 803 831 3221 fax February 26, 2007 U.S. Nuclear Regulatory Commission Attention:
Document Control Desk Washington, DC 20555-0001
Subject:
Duke Power Company LLC d/b/a Duke Energy Carolinas, LLC (Duke)
Catawba Nuclear Station, Units 1 and 2 Docket Numbers 50-413 and 50-414 Inspection and Mitigation of Alloy 82/182 Pressurizer Butt Welds
Reference:
Letter from Duke to NRC, same subject, dated February 8, 2007 On February 20,
- 2007, a telephone conference call was held among various Duke and NRC representatives to discuss the subject issue and the reference letter.
Following this conference call, on February 21,
- 2007, a verbal notification was made to the NRR Project Manager that Catawba would commit to the actions requested by the NRC in the conference call.
The purpose of this letter is to formalize this commitment.
The commitment actions are delineated in the attachment to this letter.
If there are any questions, please contact L.J. Rudy at (803) 831-3084.
Very truly yours, es R.
Morris LJR/s Attachment www. duke-energy. com A/ci
U.S. Nuclear Regulatory Commission Page 2 February 26, 2007 xc (with attachment):
W.D. Travers, Regional Administrator U.S. Nuclear Regulatory Commission, Region II Atlanta Federal Center 61 Forsyth St.,
SW, Suite 23T85 Atlanta, GA 30303 A.T. Sabisch, Senior Resident Inspector U.S. Nuclear Regulatory Commission Catawba Nuclear Station J.F. Stang, Jr., Senior Project Manager (addressee only)
U.S. Nuclear Regulatory Commission Mail Stop 0-8 H4A Washington, D.C.
20555-0001
Attachment List of NRC Commitments Commitment Effective Date and Duration of Commitment For Unit 2, Catawba commits to implementing the following:
- 1)
Unidentified leakage will be determined every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> (a 25% grace period may be applied) whenever the unit is in Modes 1, 2,
or 3.
- 2)
The following RCS leakage monitoring action levels will be implemented:
A.
If there is a 0.1 gpm increase above a recent average value from one day to the next which is sustained for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, with at least 0.1 gpm not confirmed from sources other than the pressurizer nozzle welds, then Unit 2 shall be placed in Mode 3 within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in Mode 5 within the following 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
Also, a bare metal visual inspection of the pressurizer nozzle welds containing Alloy 82/182 weld material shall be performed.
The recent average value is determined on a rolling basis from data obtained over the previous 5 to 7 days of Mode 1 full power steady state operation.
B.
If there is a 0.25 gpm increase above the baseline value which is sustained for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, with at least 0.25 gpm not confirmed from sources other than the pressurizer nozzle welds, then Unit 2 shall be placed in Mode 3 within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in Mode 5 within the following 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
- Also, a bare metal visual inspection of the This commitment will be implemented by 0000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> on March 1, 2007 and will remain in place until the Unit 2 pressurizer nozzle welds are mitigated during the End-of-Cycle 15 Refueling Outage in the Fall of 2007.
Attachment Page 1
pressurizer nozzle welds containing Alloy 82/182 weld material shall be performed.
The baseline value is determined from data obtained during the first 7 days of Mode 1 full power steady state operation after the most recent bare metal visual inspection.
For both action levels, the steady state provisions of Technical Specification 3.4.13, "RCS Operational LEAKAGE",
may be applied.
For Unit 2, Catawba commits to either December 31, inspecting or mitigating the pressurizer nozzle 2007 welds containing Alloy 82/182 weld material no later than December 31, 2007.
Duke will not revise the above commitments without prior NRC approval.
Regarding conference call discussion items pertaining to reporting requirements and reinspection frequency, the following information is provided:
Reporting Requirements -
It was noted by Duke and concurred with by the NRC that followup correspondence required by Catawba's Request for Relief 07-GO-001 submittal will satisfy any 60-day reporting requirements.
Reinspection Frequency -
Unit l's pressurizer nozzle welds were successfully mitigated during the End-of-Cycle 16 Refueling Outage in the Fall of 2006.
When Unit 2's pressurizer nozzle welds are mitigated during the End-of-Cycle 15 Refueling Outage in the Fall of 2007, this issue will be closed out for Catawba.
Therefore, there is no need for a 4-year reinspection frequency.
Attachment Page 2