ML12114A060

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Cover Letter - Revision to the Sequoyah Unit 2 Steam Generator Replacement Rigging and Heavy Load Handling Technical Report, SQN2-SGR-TR1, Submitted in Tva'S Heavy Load Lifts and UHS One Time Change in Support of Unit 2 SGRP
ML12114A060
Person / Time
Site: Sequoyah Tennessee Valley Authority icon.png
Issue date: 04/05/2012
From: John Carlin
Tennessee Valley Authority
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME7225
Download: ML12114A060 (4)


Text

Tennessee Valley Authority, Post Office Box 2000, Soddy Daisy, Tennessee 37384-2000 April 5, 2012 10 CFR 50.4 10 CFR 50.90 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Sequoyah Nuclear Plant, Unit 1 Facility Operating License No. DPR-77 Docket No. 50-327

Subject:

Revision to the Sequoyah Unit 2 Steam Generator Replacement Rigging and Heavy Load Handling Technical Report, SQN2-SGR-TRI, Submitted in TVA's Heavy Load Lifts and UHS One Time Change in Support of Unit 2 SGRP (TAC NO. ME7225)

Reference:

1. Letter from TVA to NRC, "Application to Revise Sequoyah Nuclear Plant, Unit 1, Operating License and Technical Specification 3.7.5, "Ultimate Heat Sink," to Support Sequoyah Nuclear Plant, Unit 2, Steam Generator Replacement Project (TS-SQN-2011-05)," dated September 29, 2011
2. Electronic Mail from NRC to TVA, "Sequoyah, Unit 1 LAR - Heavy Load Lifts and UHS One Time Change in Support of Unit 2 SGRP (TAC NO. ME7225)," dated January 13, 2012
3. Letter from TVA to NRC, "Response to NRC Request for Additional Information Regarding the Heavy Load Lifts and UHS One Time Change in Support of Unit 2 SGRP (TAC NO.

ME7225)," dated February 10, 2012

4. Electronic Mail from NRC to TVA, "Sequoyah, Unit 1 LAR - Heavy Load Lifts and UHS One Time Change in Support of Unit 2 SGRP (TAC NO. ME7225)," dated February 2, 2012
5. Letter from TVA to NRC, "Response to Second NRC Request for Additional Information Regarding the Heavy Load Lifts and UHS One Time Change in Support of Unit 2 SGRP (TAC NO.

ME7225)," dated March 5, 2012

U.S. Nuclear Regulatory Commission Page 2 April 5, 2012 The purpose of this letter is to submit Revision 3 of the Sequoyah Unit 2 Steam Generator Replacement Rigging and Heavy Load Handling Technical Report, SQN2-SGR-TR1.

By letter dated September 29, 2011 (Reference 1), the Tennessee Valley Authority (TVA) submitted a one-time request for amendment to the Operating License (OL) for Sequoyah Nuclear Plant (SQN), Unit 1. The amendment request proposed to add a one-time license condition to the SQN, Unit 1, OL for the conduct of heavy load lifts associated with the SQN, Unit 2, Steam Generator Replacement Project (SGRP). The one-time license condition establishes special provisions and requirements for the safe operation of SQN, Unit 1, while large heavy load lifts are performed on SQN, Unit 2. In addition, a one-time change to SQN, Unit 1, Technical Specification (TS) 3.7.5, "Ultimate Heat Sink," is also proposed to implement additional restrictions with respect to maximum average Essential Raw Cooling Water System supply header water temperature during large heavy load lifts performed to support the SQN, Unit 2, SGRP.

By electronic mail dated January 13, 2012, (Reference 2), the NRC forwarded a request for additional information (RAI) regarding the proposed changes establishing the special provisions and requirements for large heavy load lifts on SQN, Unit 2.

TVA responded to this first RAI by letter dated February 10, 2012 (Reference 3).

Subsequently, by electronic mail dated February 2, 2012, the NRC forwarded a second RAI. TVA responded to the second RAI by letter dated March 5, 2012 (Reference 5).

Since submittal of the Reference 5 response to the second RAI, an alternate interfacing lift point for removal of the old steam generators (OSGs) has been identified. In Enclosure 2 to Reference 1, TVA provided the Sequoyah Unit 2 Steam Generator Replacement Rigging and Heavy Load Handling Technical Report, SQN2-SGR-TR1, Revision 2. This Technical Report documents the provisions made to ensure that heavy load handling activities associated with the Unit 2 SGRP Outage can be accomplished without impacting the safe operation of Unit 1. Section 5.1, "Description of Cranes and Heavy Loads, Outside Lift System," of Revision 2 of the Technical Report describes using a lifting lug welded to the Main Steam nozzle as the interfacing lift point for removal of the OSGs. The alternate OSG interfacing lift point revises the interfacing lift point from the lifting lug to the secondary side manways, which will be fitted with keeper plates to enable slings to be utilized to rig out the OSGs. The secondary side manway lift point is described in Section 5.1 of Revision 3 of the Technical Report provided in Enclosure 1 to this letter.

U.S. Nuclear Regulatory Commission Page 3 April 5, 2012 Utilizing the secondary side manways as the OSG interfacing lift point eliminates the ignition sources in the Containment Building associated with welding the lifting lug to the Main Steam nozzle, including the post-weld heat treatment processes.

Eliminating the ignition sources improves the safety of personnel working in the Containment Building during the welding processes. In addition, using the secondary side manways is considered a more efficient method for removal of the OSGs which reduces the likelihood of human error by reducing complexity.

Furthermore, since the OSG removal task activity duration will be reduced, there will be a corresponding reduction in personnel radiation exposure.

Revision 3 of the Technical Report in Enclosure 1 to this letter supersedes in its entirety, Revision 2 of the Technical Report previously submitted in Enclosure 2 of Reference 1. In addition to the interfacing lift point revision described above, the following changes are also included in Revision 3 to the Technical Report:

  • Added valve numbers to Figures 6-1 and 8-2 as addressed in the response to RAI Question 2 of the enclosure to Reference 5;
  • Corrected the test weight;
  • Changed Figure 5-3 to illustrate raising the Outside Lift System foundation by 6 inches;
  • Changed the reference to "Liebherr 1400/1" crane to be "Liebherr 1400/1 or Liebherr 1400/2" to permit use of either crane; and,
  • Made changes to reflect the updated Replacement Steam Generator rigging weight.

The changes are identified by revision bars in the Technical Report provided in to this letter. Enclosure 2 to this letter provides an affected page listing of each of the changes included in Revision 3 of the Technical Report.

TVA has evaluated the revision to the OSG interfacing lift point and the other changes made in Revision 3 of the Technical Report and determined that there is no impact on the no significant hazards considerations associated with the OL and TS amendment request submitted in Reference 1. TVA has further determined that the proposed amendment still qualifies for a categorical exclusion from environmental review pursuant to the provision of 10 CFR 510.22(c)(9). In addition, TVA has concluded that there is no change to the Probabilistic Risk Assessment (PRA)

Insights as documented in Section 9.0 of the Technical Report. In accordance with 10 CFR 50.91 (b)(1), TVA is sending a copy of this letter and enclosures to the Tennessee State Department of Environment and Conservation.

U.S. Nuclear Regulatory Commission Page 4 April 5, 2012 There are no regulatory commitments included in this submittal. If you have any questions, please contact Clyde Mackaman at (423) 751-2834.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 9" day of April 2012.

Resp~vc~tfully, Vice President Sequoyah Nuclear Plant

Enclosures:

1. Sequoyah Unit 2 Steam Generator Replacement Rigging and Heavy Load Handling Technical Report, SQN2-SGR-TR1, Revision 3
2. SQN2-SGR-TR1 Revision 3 Affected Page List cc: (Enclosures):

NRC Regional Administrator - Region II NRC Senior Resident Inspector - Sequoyah Nuclear Plant Director, Division of Radiological Health, Tennessee State Department of Environment and Conservation