RC-16-0031, License Amendment Request - LAR-12-04269, License Basis Changes in Steam Generator Tube Rupture Analysis Supplement Response

License Amendment Request - LAR-12-04269, License Basis Changes in Steam Generator Tube Rupture Analysis Supplement Response

ML16068A176
Person / Time
Site:	Summer
Issue date:	03/04/2016
From:	Lippard G South Carolina Electric & Gas Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
CAC MF4699, RC-16-0031
Download: ML16068A176 (5)

Text

George A. Lippard Vice President, Nuclear Operations 803.345.4810 A SCANA COMPANY March 4, 2016 RC-1 6-0031 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Attn: S. A. Williams

Subject:

VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSE AMENDMENT REQUEST - LAR-12-04269 LICENSE BASIS CHANGES IN STEAM GENERATOR TUBE RUPTURE ANALYSIS SUPPLEMENTAL RESPONSE

References:

1. SCE&G Letter from Thomas D. Gatlin to NRC Document Control Desk, License Amendment Request - LAR-1 2-04269, "License Basis Changes in Steam Generator Tube Rupture Analysis," dated August 27, 2014

[ML14245A408]

2. NRC Letter from Shawn A. Williams to Thomas D. Gatlin, "Virgil C. Summer Nuclear Station, Unit No. I - Request for Additional Information Regarding License Basis Changes in Steam Generator Tube Rupture Analysis (CAC NO.

MF4699)," dated December 1, 2015 [ML15320A338]

3. SCE&G Letter from Thomas D. Gatlin to NRC Document Control Desk, License Amendment Request - LAR-1 2-04269, "License Basis Changes in Steam Generator Tube Rupture Analysis Response to Request for Additional Information," dated January 14, 2016 [ML16020A498]

South Carolina Electric & Gas Company (SCE&G), acting for itself and as agent for South Carolina Public Service Authority pursuant to 10 CER 50.90, submitted License Amendment Request (LAR) per Reference 1 concerning license basis changes in the steam generator tube rupture analysis. NRC review of this request determined that additional information was required and a request for additional information (RAI) was issued per Reference 2. VCSNS is providing this submittal as supplemental information to Reference 3 dated January 14, 2016.

There are no regulatory commitments associated with this response.

If you have any questions regarding this submittal, please contact Mr. Bruce L. Thompson at (803) 931-5042.

/+oo1 V.C.Summer Nuclear Station. P.0.Box 88. Jenkinsville, SC. 29065. F(803) 941-9776

Document Control Desk CR-I12-04269 RC- 16-0031 Page 2 of 2 I certify under penalty of perjury that the foregoing is correct and true.

Executed .on TS/GAL/wt

Attachment:

VCSNS Supplemental Response to Request for Additional Information c: K. B. Marsh S. A. Byrne J. B. Archie N. S. Camns J. H. Hamilton J. W. Williams W. M. Cherry C. Haney S. A. Williams NRC Resident Inspector S. E. Jenkins Paulette Ledbetter K. M. Sutton NSRC RTS (CR-I12-0426 9)

Files (813.20)

PRSF (RC-16-0031)

Document Control Desk Attachment CR-i12-04269 RC-1 6-003 1 Page 1 of 3 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 ATTACHMENT VCSNS SUPPLEMENTAL RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION

Document Control Desk Attachment CR-I12-0426 9 RC-1 6-0031 Page 2 of 3 Supplement 1: Regarding RAI No. 2 - Provide a statement that the Excel File was not used in any calculations other than presenting data.

SCE&G Response:

The Excel spreadsheet that was included in the data transmittal on January 14, 2016 accompanying letter RC-16-0006 [ML16020A498] was not used for any calculations. Rather, Excel is used as a convenient means to present tabulated data.

Supplement 2: Regarding RAI No. 3 - "In terms of the percentage difference, a maximum difference of 18.3% was calculated by the licensee. To accommodate the variation with respect to the dose acceptance criteria, the licensee indicated that the 18.3 percent difference observed at the EAB would be increased further to 20 percent and then be applied to the dose consequences at the EAB and the LPZ for the SGTR. However, the licensee has calculated the percentage change with respect to the 12-group data instead of its original 7-group data. If the calculation is done correctly, a 22.4% difference will result instead of 18.3%. This percentage difference in %I/Q, though higher than the difference stated by the licensee, will not result in a substantial change to dose."

SCE&G Response:

V.C. Summer agrees that the calculated percentage difference of 18.3 percent was inappropriate. The percent difference calculation results previously provided used the 12-wind speed group Exclusion Area Boundary (EAB) XIQ as the reference value to illustrate the negative percentage change relative to the 7-wind speed group data. If the reference values were reversed, a positive but slightly higher percentage difference of about 22 percent would be observed. As the NRC staff stated above, the change in dose will not be substantial. Thus, in order to continue to use the 7-wind speed group zIQs and account for the higher percentage difference due to the 12-wind speed group, a factor of 25 percent will be applied to all of the dose results. This is shown in the response below for Supplement 3.

Supplement 3: Taking into account any correction based on the above, provide your final xI/Q values and dose values.

SCE&G Response Table 1 shows the EAB and Low Population Zone (LPZ) x/ values that are based on the 7-wind speed groups of the 2012-2014 periods previously provided in V.C. Summer's January 14, 2016 response [ML16020A498], along with the Control Room (CR) values that were previously provided in Table 1 of V.C. Summer's November 5, 2015 response

[ML15313A023]. These will be the final %/Q values that will be used in the Updated Final Safety Analysis Report to be chosen as the latest representative characterization of site meteorology.

Document Control Desk Attachment CR-I12-04269 RC-1 6-003 1 Page 3 of 3 Table I Time Period x/Q (s/rn 3)

EAB LPZ CR 0 - 2 hrs 1.25E-4 5.97E-5a I1.50E-3 0 - 8hrs --- 2.91E-5 1.12E-3 8 - 24 hrs --- 2.03E-5 5.24E-4 1 -4 days --- 9.30E-6 3.61E-4 4 - 30 days --- 3.03E-6 2.33E-4 Table Notes:

a. 0 to 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> LPZ %/Q value is used only for the Fuel Handling Accident.

b. 2 to 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> x/ value is used for CR only in the Main Steam Line Break, SGTR, Locked Rotor Accident, and Control Rod Ejection accidents.

The first set of columns of Table 2 shows the final dose results for the supplementary SGTR case reported in V.0. Summer's LAR-12-04269 submittal [ML14245A408]. These reflect the highest and thus, most conservative set of values calculated regardless of %/Qused as input.

As stated in the response to Supplement 2 and as shown in the second set of columns, these values are augmented by 25 percent, to accommodate the largest absolute value in percent difference between the 7- and 12-wind speed group x/Qs. These values will be the final %/Q values and does values to be applied in V.C. Summer's design and licensing bases.

These doses reflect the 'Hand Calc' scenario, wherein a non-mechanistic, constant, and thus conservative primary-to-secondary mass release is evaluated. It also reflects the Alternative Source Term methods. In all cases, the TEDE limits continue to be met.

Table 2 SGTR Augmented Doses LAR 12-04269 Doses (REM) for LAR 12-04269 Augmented Doses Supplementary Case (REM) (x1 .25) for Supplementary Case to be Used as Final Dose Values EAB LPZ CR EAB LPZ CR (0-2h) 0-24h) 0-30d) 0-2h) (0-24h (0-30d)

Pre- 0.68 0.28 1.30 0.85 0.35 1.63 Accident Spike _____

TEDE Limit 25 25 5 25 25 5 Concurrent 0.31 0.14 0.50 0.39 0.18 0.63 Spike_____

TEDE Limit 2.5 2.5 5 2.5 2.5 5