ML072830032

Technical Specifications (TS) Change 07-04 Revision of Core Operating Limits Report (COLR) References for Realistic Large Break Loss of Coolant Accident Methodology Supplemental Information

ML072830032
Person / Time
Site:	Sequoyah
Issue date:	10/03/2007
From:	Morris G Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TVA-SQN-TS-07-04 ANP-2655(NP), Rev. 00
Download: ML072830032 (14)

Text

Tennessee Valley Authority, Post Office Box 2000, Soddy-Daisy, Tennessee 37384-2000 October 3, 2007 TVA-SQN-TS-07-04 10 CFR 50.90 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Gentlemen:

In the Matter of ) Docket No. 50-328 Tennessee Valley Authority )

SEQUOYAH NUCLEAR PLANT (SQN) - UNIT 2 - TECHNICAL SPECIFICATIONS (TS)

CHANGE 07-04 "REVISION OF CORE OPERATING LIMITS REPORT (COLR)

REFERENCES FOR REALISTIC LARGE BREAK LOSS OF COOLANT ACCIDENT METHODOLOGY SUPPLEMENTAL INFORMATION" On July 26, 2007, TVA submitted TS Change 07-04 pursuant to 10 CFR 50.90, to add a new reference in TS Section 6.9.1.14.a. NRC's review of SQN TS Change 07-04 identified an inconsistency in the methodology with respect to the requirements of General Design Criteria 35 "Emergency Core Cooling" in that offsite power availability should not have been sampled.

To determine the effect of sampling offsite power availability, the cases reported in ANF-2655P, Revision 00 were ran with the opposite choice for offsite power availability.

That is, base cases with offsite power available were ran with offsite power not available, and base cases with offsite power not available were ran with offsite power available. All other sampled parameters for each base case were unchanged. It is concluded that the set of cases submitted in Topical Report ANF-2655(P), Revision 00 is limiting relative to estimating the 95 percent peak clad temperature (PCT) and the estimated 95 percent PCT is unaffected by sampling offsite power availability.

Prilted on re ,iled paper

U.S. Nuclear Regulatory Commission Page 2 October 3, 2007 provides supplementary information pertaining to the SQN realistic large break loss of coolant accident methodology. Portions of Enclosure 1 are proprietary to Areva Nuclear Power (NP). Enclosure 2 provides a non-proprietary version of the document contained in Enclosure 1.

Accordingly, Enclosure 3 includes a copy of the AREVA NP Application for Withholding Proprietary Information from public disclosure that was included with the original letter.

The affidavit sets forth the basis on which the information may be withheld from public disclosure by the Commission, and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR 2.790 of the Commission's regulations. TVA respectfully requests that the AREVA NP proprietary information be withheld from public disclosure in accordance with 10 CFR 2.390.

TVA determined this information does not affect the no significant hazards considerations associated with the proposed change and the TS change qualifies for categorical exclusion from environmental review pursuant to the provisions of 10 CFR 51.22(c)(9).

Additionally, 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 Public Health.

There are no commitments contained in this submittal.

If you have any questions about this change, please contact me at 843-7170.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this 3rd day of October, 2007.

Sincerely, Glenn W. Morris Manager, Site Licensing and Industry Affairs

Enclosures:

1. Proprietary Version of SQN's Plant Specific Topical

2. Non-Proprietary Version of SQN's Plant Specific Topical

3. AREVA NP Affidavit for Withholding of Proprietary Information

U.S. Nuclear Regulatory Commission Page 3 October 3, 2007 Enclosures cc (Enclosures):

Mr. Brendan T. Moroney, Senior Project Manager U.S. Nuclear Regulatory Commission Mail Stop 08G-9a One White Flint North 11555 Rockville Pike Rockville, Maryland 20852-2739 Mr. Lawrence E. Nanney, Director Division of Radiological Health Third Floor L&C Annex 401 Church Street Nashville, Tennessee 37243-1532

ENCLOSURE2 TENNESSEE VALLEY AUTHORITY (TVA)

SEQUOYAH NUCLEAR PLANT (SQN)

UNIT 2 NON-PROPRIETARY INFORMATION REALISTIC LARGE BREAK LOSS OF COOLANT ACCIDENT ANALYSIS ANP-2655(P)

REVISION 0 September 17, 2007 E2-1

AREVA NP Inc.

Sequoyah Nuclear Plant Unit 2 ANP-2655(NP)(Q)

Realistic Large Break LOCA Analysis Revision 00 Page 1 9/17/2007 Supplemental Information on the Sequoyah RLBLOCA Submittal Provided herein is supplemental information concerning the sampling of'offsite power availability' in the Sequoyah Unit 2 realistic large break LOCA (RLBLOCA) submittal, topical report ANF-2655P Revision 00.

To determine the effect of sampling offsite power availability, the cases reported in ANF-2655P Revision 00 were rerun with the opposite choice for offsite power availability.

That is, base cases with offsite power available were rerun with offsite power not available and base cases with offsite power not available were rerun with offsite power available. All other sampled parameters for each base case were unchanged. Since only offsite power availability was changed between the base and reanalysis cases, one can construct a set of

59. cases with offsite power available and a second set of 59 cases with offsite power not available. The PCTs for these two sets, order from the highest to the lowest PCTs, are shown in Figures 1 and 2. Figure 3 is a bar chart showing the sensitivity of switching the offsite power availability sampling result from that of the base set of cases. The ordering in Figure 3 is by the case number (cases 1 to 59) associated with each of the 59 base cases.

In Figure 4 the red triangles are the base set of 59 cases, while the blue squares represent the reanalysis with offsite power availability switched. The solid symbols are for offsite power available and the open symbols are for offsite power not available. The ordering in Figure 4 is by PCT from the base set of cases. The switched set of cases is presented in the order of the base set of cases. Like Figure 3, Figure 4 shows the individual case sensitivity.

Sampling of offsite power availability within the AREVA RLBLOCA evaluation model (EM) is primarily a study in [

]. Of secondary importance is the link of the [ ]to offsite power availability. This is so because [ ] generally[ ] to the end of

[ ]. The single failure assumption-the complete loss of one train (high, medium and low head injection for Sequoyah) of ECCS injection-is [ ]

offsite power availability sampling. Also containment pressure suppression-all cooling systems (sprays and fan coolers) are fully functional with [ ]-is [ ]

both the [ ] and offsite power availability [ ]. The parameter of interest is perhaps better termed [ ] since it actual [

].

Comparing the two sets of 59 cases, the following is observed:

1. The base limiting case, Number 44 in ANP-2655P Revision 00, remains limiting. This case was for RCPs un-powered (offsite power not available). Changing to powered RCPs decreased the PCT slightly (see Figure 4). The maximum PCT remains at 1,967 -F.

2. [

]. This can be seen in Figure 4.

AREVA NP Inc.

.Sequoyah Nuclear Plant Unit 2 ANP-2655(NP)(Q)

Realistic Large Break LOCA Analysis Revision 00 Page 2 9/17/2007 It is concluded that the set of cases submitted in topical report ANF-2655(P) Revision 00 is limiting relative to estimating the 95 percent PCT and that the estimated 95 percent PCT is unaffected by sampling offsite power availability.

AREVA NP Inc.

Sequoyah Nuclear Plant Unit 2 ANP-2655(NP)(Q)

Realistic Large Break LOCA Analysis Revision 00 Page 3 9/17/2007 Figure 1: Offsite Power Available

AREVA NP Inc.

Sequoyah Nuclear Plant Unit 2 ANP-2655(NP)(Q)

Realistic Large Break LOCA Analysis Revision 00 Page 4 9/17/2007 Figure 2: Offsite Power Not Available

AREVA NP Inc.

Sequoyah Nuclear Plant Unit 2 ANP-2655(NP)(Q)

Realistic Large Break LOCA Analysis Revision 00 Page 5 9/17/2007 Figure 3: Effect of Switching Offsite Power Availability

AREVA NP Inc.

Sequoyah Nuclear Plant Unit 2 ANP-2655(NP)(Q)

Realistic Large Break LOCA Analysis Revision 00 Page 6 9/17/2007 Figure 4: Effect of Switching Offsite Power Availability

ENCLOSURE3 TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT (SQN)

UNIT 2 PROPRIETARY INFORMATION WITHHOLDING AFFIDAVIT E3-1

AFFIDAVIT COMMONWEALTH OF VIRGINIA )

) ss.

CITY OF LYNCHBURG )

1. My name is Gayle F. Elliott. I am Manager, Product Licensing, forAREVA NP Inc. and as such I am authorized to execute this Affidavit.

2. I am familiar with the criteria applied by AREVA NP to determine whether certain AREVA NP information is proprietary. I am familiar with the policies established by AREVA NP to ensure the proper application of these criteria.

3. I am familiar with the AREVA NP information contained in the report ANP-

.2655(P), Revision 0, "Sequoyah Unit 2 Nuclear Plant Realistic Large Break LOCA Analysis,"

dated June 2007, and referred to herein as "Document.." Information contained in this Document has been classified by AREVA NP as proprietary in accordance with the policies established by AREVA NP for the control and protection of proprietary and confidential information.

4. This Document contains information of a proprietary and confidential nature and is of the type customarily held in confidence by AREVA NP and not made available to the public. Based on my experience, I am aware that other companies regard information of the kind contained in this Document as proprietary and confidential.

5. This Document has been made available to the U.S. Nuclear Regulatory Commission in confidence with the request that the information contained in this Document be withheld from public disclosure. The request for withholding of proprietary information is made in accordance with 10 CFR 2.390. . The information for which withholding from disclosure is

requested qualifies under 10 CFR 2.390(a)(4) "Trade secrets and commercial or financial information."

6. The following criteria are customarily applied by AREVA NP to determine whether information should be classified as proprietary:

(a) The information reveals details of AREVA NP's research and development plans and programs or their results.

(b) Use of the information by a competitor would permit the competitor to significantly reduce its expenditures, in time or resources, to design, produce, or market a similar product or service.

(c) The information includes test data or analytical techniques concerning a process, methodology, or component, the application of which results in a competitive advantage for AREVA NP.

(d) The information reveals certain distinguishing aspects of a process, methodology, or component, the exclusive use of which provides a competitive advantage for AREVA NP in product optimization or marketability.

(e) The information is vital to a competitive advantage held by AREVA NP, would be helpful to competitors to AREVA NP, and would likely cause substantial harm to the competitive position of AREVA NP.

The information in the Document is considered proprietary for the reasons set forth in paragraphs 6(b) and 6(c) above.

7. In accordance with AREVA NP's policies governing the protection and control of information, proprietary information contained in this Document have been made available, on a limited basis, to others outside AREVA NP only as required and under suitable agreement providing for nondisclosure and limited use of the information.

8. AREVA NP policy requires that proprietary information be kept in a secured file or area and distributed on a need-to-know basis.

9. The foregoing statements are true and correct to the best of my knowledge, information, and belief.

"*2.býJ SUBSCRIBED before me this day of VUru' I - I 2007.

Sherry L. McFaden NOTARY PUBLIC, COMMONWEALTH OF VIRGINIA MY COMMISSION EXPIRES: 10/31/10