L-07-031, Mitigation of Alloy 82-182 Pressurizer Butt Welds and Enhanced Reactor Coolant System Leakage Monitoring Program

Mitigation of Alloy 82-182 Pressurizer Butt Welds and Enhanced Reactor Coolant System Leakage Monitoring Program

ML070640092
Person / Time
Site:	Beaver Valley
Issue date:	02/23/2007
From:	Lash J FirstEnergy Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-07-031
Download: ML070640092 (6)

Text

FENOC FirstEnergyNuclear OperatingCompany James H. Lash 724-682-5234 Site Vice President Fax: 724-643-8069 February 23, 2007 L-07-031 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Beaver Valley Power Station, Unit No. 1 Docket No. 50-334, License No. DPR-66 Docket No. 50-412, License No. NPF-73 Mitigation of Alloy 82/182 Pressurizer Butt Welds and Enhanced Reactor Coolant System Leakage Monitoring Program By letter dated January 31, 2007 (L-07-022), FirstEnergy Nuclear Operating Company (FENOC) provided the Nuclear Regulatory Commission (NRC) with information related to Alloy 82/182 pressurizer butt welds. The letter confirmed completion of inspection and mitigation activities at Beaver Valley Power Station Unit No. 2 (BVPS-2) during the 2006 refueling outage, outlined planned activities for Beaver Valley Power Station Unit No. I (BVPS-1) weld mitigation, and provided details regarding current Reactor Coolant System (RCS) leakage monitoring programs.

During a February 15, 2007 teleconference, the NRC staff provided feedback relevant to the adequacy of BVPS-1 RCS leakage monitoring program with associated reporting requirements and proposed additional details necessary to address NRC concerns. During a teleconference with NRC staff on February 16, 2007, FENOC provided verbal confirmation of the intent to establish regulatory commitments for the proposed leakage monitoring program enhancements.

Specific details of the enhanced RCS leakage monitoring program are provided in Attachment 1.

Regulatory commitments associated with this letter are listed in Attachment 2, and supersede in their entirety the regulatory commitments established by FENOC in the January 31, 2007 letter.

If there are any questions or if additional information is required, please contact Mr. Gregory H. Halnon, Director - FENOC Fleet Regulatory Affairs at (330) 315-7500.

Sincerely, ames H. Lash A4110

'Beaver Valley Power Station, Unit Nos. I & 2 L-07-031 Attachment 1 Page 2 Attachments:

1. Mitigation of Alloy 82/182 Pressurizer Butt Welds and Enhanced Reactor Coolant System Leakage Monitoring Program.

2. Regulatory Commitments.

cc: Ms. N. Morgan, NRR Senior Project Manager Mr. P. C. Cataldo, NRC Senior Resident Inspector Mr. S. J. Collins, NRC Region I Administrator Mr. D. A. Allard, Director BRP/DEP Mr. L. E. Ryan (BRP/DEP)

Beaver Valley Power Station, Unit Nos. 1 & 2 L-07-031 Page 1 of 2 Mitigation of Alloy 82/182 Pressurizer Butt Welds and Enhanced Reactor Coolant System Leakage Monitorin2 Pro2ram As previously communicated to the NRC by letter dated January 31, 2007, and discussed during a teleconference on February 15, 2007, BVPS-2 Alloy 82/182 pressurizer butt weld mitigation activities are complete. Therefore, an enhanced RCS leakage monitoring program is not necessary for BVPS-2.

During the fall 2007 refueling outage, FENOC will perform mitigation activities and conduct the required inspections for the BVPS-1 Alloy 82/182 pressurizer butt welds. In order to alleviate RCS leakage concerns prior to weld mitigation, an enhanced RCS leakage monitoring program will be implemented at BVPS-1. The program will contain the following elements:

" Daily RCS leakage monitoring will be performed while in Modes 1, 2, or 3.

" The following action levels will be incorporated:

a. 0.1 gpm change from one day to the next, 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 susceptible and unmitigated pressurizer nozzle welds.

b. 0.25 gpm above a baseline, 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 susceptible and unmitigated pressurizer nozzle welds.

" The baseline for RCS leakage monitoring will be established following seven days of full power operation following the last bare metal visual inspection. The current baseline for BVPS-1 is 0.0 gallons per minute, and was established by using data generated during the first seven days of full power operation following the last refueling outage.

" The following action level response will be incorporated into the BVPS-l RCS leakage monitoring program:

Once a 72-hour evaluation period is complete, and leak rate is still elevated, place the unit in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and Mode 5 within the next 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, and perform bare metal visual inspections of unmitigated pressurizer spray, safety, and relief nozzle butt welds and safe-end butt welds containing Alloy 82/182 material.

" Details of any corrective or mitigative actions taken will be reported within 60 days of unit restart, and results of any bare metal visual inspections will be reported within 60 days of unit restart.

• Alloy 82/182 pressurizer butt welds that are not mitigated or removed from service will be re-inspected every four years.

"Beaver Valley Power Station, Unit Nos. 1 & 2 L-07-031 Attachment 1 Page 2 of 2 Each of the activities related to the RCS leakage monitoring program will be incorporated into BVPS-1 procedures or daily instructions before March 1, 2007, and will remain in effect until completion of Alloy 82/182 pressurizer butt weld mitigation activities at BVPS-1. In accordance with FENOC's commitment management program and Nuclear Energy Institute's "Guideline for Managing NRC Commitments," the NRC will be notified, in writing, in advance of any changes to these commitments.

Beaver Valley Power Station, Unit Nos. 1 & 2 L-07-031 Page 1 of2 Re2ulatory Commitments The following list identifies those actions committed to by FirstEnergy Nuclear Operating Company (FENOC) for Beaver Valley Power Station (BVPS) Unit No. 1 in this document. Any other actions discussed in the submittal represent intended or planned actions by FENOC. They are described only as information and are not regulatory commitments. Please notify Mr. Gregory H. Halnon, Director - Fleet Regulatory Affairs at 330-315-7500 of any questions regarding this document or associated regulatory commitments.

Commitment Due Date

1. During the fall 2007 refueling outage, FENOC will perform Prior to startup after mitigation activities and conduct the required inspections for the the fall 2007 BVPS-1 Alloy 82/182 pressurizer butt welds. refueling outage.

2. In order to alleviate RCS leakage concerns prior to weld mitigation, February 28, 2007 an enhanced RCS leakage monitoring program will be implemented at BVPS-1. The program will contain the following elements:

" Daily RCS leakage monitoring will be performed while in Modes 1,2, or 3.

" The following action levels will be incorporated:

a. 0.1 gpm change from one day to the next, 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 susceptible and unmitigated pressurizer nozzle welds.

b. 0.25 gpm above a baseline, 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 susceptible and unmitigated pressurizer nozzle welds.

" The baseline for RCS leakage monitoring will be established following seven days of full power operation following the last bare metal visual inspection.

" The following action level response will be incorporated into the BVPS-1 RCS leakage monitoring program:

Once a 72-hour evaluation period is complete, and leak rate is still elevated, place the unit in Mode 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and Mode 5 within the next 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, and perform bare metal visual inspections of unmitigated pressurizer spray, safety, and relief nozzle butt welds and safe-end butt welds containing Alloy 82/182 material.

(Continued)

• BeaverValley Power Station, Unit Nos. 1 & 2 L-07-031 Page 2 of 2 Commitment Due Date

2. In order to alleviate RCS leakage concerns prior to weld mitigation, an enhanced RCS leakage monitoring program will be implemented at BVPS-1. The program will contain the following elements (continued from previous page):

" Details of any corrective or mitigative actions taken will be reported within 60 days of unit restart, and results of any bare metal visual inspections will be reported within 60 days of unit restart.

" Alloy 82/182 pressurizer butt welds that are not mitigated or removed from service will be re-inspected every four years.

Each of the activities related to the RCS leakage monitoring program will be incorporated into BVPS-1 procedures or daily instructions before March 1, 2007, and will remain in effect until completion of Alloy 82/182 pressurizer butt weld mitigation activities at BVPS-1.

3. In accordance with FENOC's commitment management program and Ongoing Nuclear Energy Institute's "Guideline for Managing NRC Commitments," the NRC will be notified, in writing, in advance of any changes to these commitments.