ML18066A000

Request for Additional Information Integrated Leak Rate Test Peak Calculated Containment Internal Pressure Change

ML18066A000
Person / Time
Site:	Summer
Issue date:	03/08/2018
From:	Shawn Williams Division of Operating Reactor Licensing
To:	Lippard G South Carolina Electric & Gas Co
Williams, Shawn A., 415-1009
References
EPID L-2017-LLA-0348
Download: ML18066A000 (5)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 March 8, 2018 Mr. George A. Lippard, Ill Vice President, Nuclear Operations South Carolina Electric & Gas Company Virgil C. Summer Nuclear Station Post Office Box 88, Mail Code 800 Jenkinsville, SC 29065

SUBJECT:

VIRGIL C. SUMMER NUCLEAR STATION, UNIT NO. 1 - REQUEST FOR ADDITIONAL INFORMATION RE: INTEGRATED LEAK RATE TEST PEAK CALCULATED CONTAINMENT INTERNAL PRESSURE CHANGE (EPID NO. L-2017-LLA-0348)

Dear Mr. Lippard:

By letter dated October 6, 2017, South Carolina Electric & Gas Company (the licensee) requested changes to the Technical Specifications (TS) for the for Virgil C. Summer Nuclear Plant, Unit 1.

The proposed amendment would increase the Integrated Leak Rate Test Peak Calculated Containment Internal Pressure, Pa, listed in TS 6.8.4.g, "Containment Leakage Rate Testing Program," to remove the reference to Regulatory Guide 1.163, "Performance-Based Containment Leak Test Program," dated September 1995 and ANSI/ANS-56.8-2002, "Containment System Leakage Testing Requirements," and to replace the reference of NEI 94-01, Revision 3-A, "Industry Guideline for Implementing Performance-Based option of 10 CFR Part 50, Appendix J," with NEI 94-01, Revision 2-A.

The U.S. Nuclear Regulatory Commission (NRG) staff has reviewed the licensee's submittal and determined that additional information is needed to complete its review. During a clarification call on March 5, 2018, Ms. Dalick of your staff requested 45 days from the date of this letter to respond to the NRG request for additional information. The NRG staff agreed to this request but notes that the NRG staff's review is continuing, and further requests for information may be developed.

G. Lippard If you have any questions, please contact me at 301-415-1009 or Shawn.Williams@nrc.gov.

Sincerely, Shawn A. Williams, Senior Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-395

Enclosure:

Request for Additional Information cc w/enclosure: Listserv

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST INTEGRATED LEAK RATE TEST PEAK CALCULATED CONTAINMENT INTERNAL PRESSURE CHANGE SOUTH CAROLINA ELECTRIC & GAS COMPANY VIRGIL C. SUMMER NUCLEAR STATION, UNIT NO. 1 DOCKET NO. 50-395 By letter dated October 6, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML17279A715), South Carolina Electric & Gas Company (the licensee) requested changes to the Technical Specifications (TS) for the for Virgil C. Summer Nuclear Plant, Unit 1.

The proposed amendment would increase the Integrated Leak Rate Test (ILRT) Peak Calculated Containment Internal Pressure, Pa, listed in TS 6.8.4.g, "Containment Leakage Rate Testing Program," to remove the reference to Regulatory Guide 1.163, "Performance-Based Containment Leak Test Program," dated September 1995 and ANSI/ANS-56.8-2002, "Containment System Leakage Testing Requirements," and to replace the reference of NEI 94-01, Revision 3-A, "Industry Guideline for Implementing Performance-Based Option of 10 CFR Part 50, Appendix J" (ADAMS Accession No. ML12221A202) with NEI 94-01, Revision 2-A (ADAMS Accession No. ML100620847).

The NRC staff has determined that the following requests for additional information (RAI) are required to complete its review.

RAI 1

Regulatory Basis - 10 CFR Part 50, Appendix A, Criterion 50, Containment design basis The reactor containment structure, including access openings, penetrations, and the containment heat removal system shall be designed so that the containment structure and its internal compartments can accommodate, without exceeding the design leakage rate and with sufficient margin, the calculated pressure and temperature conditions resulting from any loss-of-coolant accident. This margin shall reflect consideration of (1) the effects of potential energy sources which have not been included in the determination of the peak conditions, such as energy in steam generators and as required by § 50.44 energy from metal-water and other chemical reactions that may result from degradation but not total failure of emergency core cooling functioning, (2) the limited experience and experimental data available for defining accident phenomena and containment responses, and (3) the conservatism of the calculational model and input parameters.

Enclosure

Section 3.3 of the Reference 1 Enclosure states, in part, that:

modeling corrections were applied that slightly altered certain initial conditions in FSAR [Final Safety Analysis Report] Table 6.2-2.

Please describe the modelling correction in the Mass and Energy (M&E) release analysis that resulted in the change in the initial conditions.

RAl2:

Regulatory Basis - Same as RAI 1.

Except for the change in inputs, based on the Nuclear Safety Advisory Letters 06-6, 11-5, and 14-2, please confirm that the remaining inputs and assumptions for the M&E release, containment pressure, vapor temperature, and sump temperature response analyses are the same as in the plant analysis of record. Please state the differences in the inputs and assumptions, if any, with those in the plant analysis of record. Please justify in any conservatism is reduced in these inputs and assumptions.

RAl3:

Regulatory Basis - Same as RAI 1.

On page 9 of the Enclosure, the licensee states:

For the DEHL [Double-Ended Hot Leg] case, the releases were calculated only for the blowdown.

Please provide justification for not calculating the M&E releases and containment response for the remaining three phases of the DEHL break Loss-of-Coolant Accident, and explain quantitatively why the Double-Ended Pump Suction cases bound the plant analysis or record for the long term containment and sump temperature responses.

ML 18066AOOO *via email OFFICE DORULPLll-1/PM DORULPLll-1/LA NRR/DSS/SRXB/BC*

NAME SWilliams KGoldstein JWhitman* (A)

DATE 3/7/18 3/7/18 2/26/18 OFFICE DORULPLll-1/BC DORULPLI 1-1 /PM NAME MMarkley w/changes SWilliams DATE 3/7/18 3/8/18