ULNRC-05169, Technical Specification Revisions Associated with the Steam Generator Replacement Project

Technical Specification Revisions Associated with the Steam Generator Replacement Project

ML052070584
Person / Time
Site:	Callaway
Issue date:	07/15/2005
From:	Keith Young AmerenUE
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
ULNRC-05169
Download: ML052070584 (5)

Text

AmerenUE PO Box 620

-CallawayPlant Fulton, MIO 65251 July 15, 2005 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station P1-137 Washington, D.C. 20555 ULNRC-05169 Ladies and Gentlemen:

DOCKET NUMBER 50-483 UNION ELECTRIC COMPANY CALLAWAY PLANT w hAmern uE TECHNICAL SPECIFICATION REVISIONS ASSOCIATED WITH THE STEAM GENERATOR REPLACEMENT PROJECT

References:

1. ULNRC-05056 dated September 17,2004

2. ULNRC-05117 dated February 11, 2005

3. ULNRC-05145 dated May 26, 2005

4. ULNRC-05157 dated June 17,2005

5. ULNRC-05159 dated June 17, 2005 In Reference I above AmerenUE transmitted an application for amendment to Facility Operating License Number NPF-30 for the Callaway Plant in support of the replacement steam generators to be installed during Refuel 14 (fall 2005). This letter provides additional information on two issues recently raised by the NRC staff during the review of that application.

The amendment application included a commitment to submit additional information regarding effective mitigation measures to be applied at the Alloy 82/182 pressurizer nozzle safe end weld at the base of the pressurizer. The commitment supported evaluations contained in Appendix A of the amendment application, specifically in Section 6.5.2.3 (page 6-395) of Appendix A (WCAP-16265-P). In Reference 2 above AmerenUE responded to several requests for additional information (RAIs) from the NRC in areas involving containment integrity, plant systems, and steam generator (SG) tube integrity. In the response to question number 7 (see Attachment 4 to ULNRC-05117), the following statements were made:

"Section 6.5.2 of WCAP-16265-P discusses the analysis of the short-term LOCA-related mass and energy releases which are used as an input to the containment subcompartment analyses performed to ensure that the walls of a subcompartment can maintain their structural integrity during the short pressure pulse (generally less than 3 seconds) accompanying a high energy line pipe rupture within that subcompartment. The analysis of the pressurizer and surge line compartments assumed that the LBB methodology of WCAP-15983-P Revision 0 would be Acx")(

a subsidiary ofAmeren Corporation

ULNRC-05 169 July 15, 2005 Page 2 approved for the pressurizer surge line. Since the LBB methodology has not been approved and AmerenUE has decided to not pursue surge line LBB, additional analysis work is ongoing to confirm the acceptability of the lower end of the T-avg range (570.70 F). That additional analysis work will be completed by April 15, 2005."

In order to confirm that LBB for the pressurizer surge line is not required for the SG replacement project, analyses were performed for the pressurizer vault and for the pressurizer skirt. The pressurizer vault analysis showed less pressurization than shown in FSAR Table 6.2.1-26. Therefore, operation of Callaway at a T-avg as low as 570.70 F would not result in exceeding the pressurizer vault loading criteria in the event of a double-ended break in the pressurizer surge line; however, as stated in Reference 2, the mechanical design limitations of the steam dump system will limit the low end of the permissible T-avg range to 5730F. The pressurizer skirt pressurization analysis was reanalyzed to verify the uplift forces on the pressurizer. The newly calculated uplift load on the pressurizer can be accommodated by the pressurizer supports. These analyses have been completed and demonstrate that pressurizer surge line LBB is not required.

In Reference 3 above AmerenUE responded to several RAIs from the NRC regarding instrumentation and control issues. On July 7, 2005, AmerenUE, Westinghouse, and NRC personnel discussed the response to question number 2 in Reference 3. That response stated, in part, that "AmerenUE will trend as-found and as-left setpoint data obtained during CHANNEL OPERATIONAL TESTS (COTs) for these specific Trip Functions to confirm that the rack drift assumptions used in the plant setpoint methodology are valid. If the trending evaluation determines that a channel is performing inconsistent with the uncertainty allowances applicable to the periodic surveillance test being performed (e.g., whether it be a COT, CHANNEL CALIBRATION, etc.), the channel will be evaluated under the corrective action program. If the channel is not capable of performing its specified safety function, it shall be declared inoperable." In addition to that response, the following information is provided. For the channels affected by the SG replacement project, the Allowable Value is established at a slight difference in % of span from the Nominal Trip Setpoint by an amount equal to the Westinghouse-proprietary Rack Calibration Accuracy (RCA) in the direction toward the Safety Analysis Limit for the particular trip function. The RCA value was provided in Attachment 1 to Reference 3. If the as-found setting for any of these specific trip function channels is found to be outside the two-sided calibration tolerance band on either side of the Nominal Trip Setpoint, including any Allowable Value exceedance, then a Callaway Action Request will be written and the affected channel will be evaluated under the corrective action program. This will be done in addition to restoring the channel to within the calibration tolerance band.

References 4 and 5 above provided supplemental Technical Specification changes and additional RAI responses in support of this amendment request. Nothing in the information provided above invalidates the findings of the licensing evaluations contained in Attachment I of Reference 1. The requested approval date and

ULNRC-05 169 July 15, 2005 Page 3 implementation plans for this amendment application remain unchanged from Reference

1. If you have any further questions on this amendment application, please contact us.

Very truly yours, Keith D. Young Manager-Regulatory Affairs GGY/

ULNRC-05169 July 15, 2005 Page 4 cc: U.S. Nuclear Regulatory Commission (Original and I copy)

Attn: Document Control Desk Mail Stop P1-137 Washington, DC 20555-0001 Mr. Bruce S. Mallett Regional Administrator U.S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-4005 Senior Resident Inspector Callaway Resident Office U.S. Nuclear Regulatory Commission 8201 NRC Road Steedman, MO 65077 Mr. Jack N. Donohew (2 copies)

Licensing Project Manager, Callaway Plant Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop 7EI Washington, DC 20555-2738 Missouri Public Service Commission Governor Office Building 200 Madison Street PO Box 360 Jefferson City, MO 65102-0360 Deputy Director Department of Natural Resources P.O. Box 176 Jefferson City, MO 65102

STATE OF MISSOURI

) SS COUNTY OF CALLAWAY)

Keith D. Young, of lawful age, being first duly sworn upon oath says that he is Manager, Regulatory Affairs, for Union Electric Company; that he has read the foregoing document and knows the content thereof; that he has executed the same for and on behalf of said company with full power and authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.

By Manage, Ruatorfa i EOh D. Youhd '

Manager, Regulatory Affairs SUBSCRIBED and sworn to before me this lI day of. -WIy 2005.

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