ML12068A424

Virgil Summer Nuclear Station, Unit 1 - Request for Additional Information on Surveillance Requirements

ML12068A424
Person / Time
Site:	Summer
Issue date:	03/13/2012
From:	Martin R Plant Licensing Branch II
To:	Gatlin T South Carolina Electric & Gas Co
Martin R
References
TAC ME5011
Download: ML12068A424 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 March 13, 2012 Mr. Thomas D. Gatlin Vice President, Nuclear Operations South Carolina Electric & Gas Company Virgil C. Summer Nuclear Station Post Office Box 88 Jenkinsville, SC 29065

SUBJECT:

VIRGIL C. SUMMER NUCLEAR STATION, UNIT NO.1 (VCSNS) - REQUEST FOR ADDITIONAL INFORMATION (RAI) ON SURVEILLANDCE REQUIREMENTS (TAC NO. ME5011)

Dear Mr. Gatlin:

By letter dated November 11, 2010, the South Carolina Electric & Gas Company (SCE&G) submitted a license amendment request to revise the Technical Specifications in Appendix A to Facility Operating License Number NPF-12 for the Virgil C. Summer Nuclear Station, Unit 1.

SCE&G provided additional clarifying information in its letter dated June 16, 2011. The staff has reviewed the amendment request and the information in the June 16, 2011 letter and requests additional information, as stated in the Enclosure.

We request that a response be provided within 30 days of the date of this letter.

Sincerely,

~&~anager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-395

Enclosure:

RAI cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION REGARDING THE LICENSE AMENDMENT REQUEST TO CHANGE EMERGENCY DEIESEL GENERATOR SURVEILLAND REQUIREMENTS FOR VIRGIL C. SUMMER NUCLEAR STATION. UNIT 1 By letter dated November 11, 2010, (Agencywide Documents Access and Management System (ADAMS), Accession No. ML103190756), the South Carolina Electric & Gas Company (SCE&G) submitted a license amendment request (LAR) to revise the Technical Specifications (TS), in Appendix A to Facility Operating License Number NPF-12 for the Virgil C. Summer Nuclear Station, Unit 1, (VCSNS). The licensee provided additional clarifying information in its letter dated June 16, 2011 (ADAMS Accession No. ML11171A259). The staff has reviewed the amendment request and the information in the June 16, 2011, letter and has the following supplemental questions 1 The LAR proposed changes to SR 4.8.1.1.2.a.3 to raise the minimum allowable emergency diesel generator (EDG) bus voltage from 6480 volts to 6511 volts. The licensee has indicated that 6511 volts is the analytical limit for minimum voltage required for equipment operability. Typically, the TS values are higher than the analytical limits to ensure equipment operability after accounting for instrument errors. SR 4.8.1.1.2.a.3 requires operability of the EDG to be verified on a monthly basis. Describe the methodology used by plant operators to verify that the EDGs are capable of providing a voltage level higher than the analytical limit based on the monthly test. Provide inaccuracies of instrumentation used for this surveillance.

2. The LAR proposed changes to SR 4.8.1.1.2.a.3 which has voltage and frequency components. SR 4.8.1.1.2.a.3 provides a frequency range for EDG acceptance criteria for steady state operation. VCSNS is currently committed to RG 1.9, Revision O. The LAR cites RG 1.9, Revision 3, as a guidance document for the proposed changes. RG 1.9, Revision 3 has relaxed requirements for EDG voltage and frequency tolerances during EDG load sequencing. Verify that motor operated valve performance (in accident analyses) is not adversely impacted at the lower end of the TS allowable frequency coupled with the frequency and voltage variations allowed in RG 1.9 Rev. 3.

3 A new note is proposed at the bottom of page 3/4 8-3 to allow testing at a power factor (PF) other than 0.9 if grid conditions do not permit testing at the proposed PF. Verify whether the EDGs are routinely operated with a power factor close to 0.8 or the calculated values of o .857 (DG A) and 0.852 (DG B) during the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> test.

4. The LAR proposes a new SR 4.8.1.1.2.g.15 to replace 4.8.1.1.2.g.6.c for testing EDG trips that are bypassed. Confirm that the surveillance testing using the proposed SR will verify the operation of contacts used in a) the trip circuits that are active and b) circuits that are bypassed during emergency operation.

Enclosure

March 13, 2012 Mr. Thomas D. Gatlin Vice President, Nuclear Operations South Carolina Electric & Gas Company Virgil C. Summer Nuclear Station Post Office Box 88 Jenkinsville, SC 29065 SUB..IECT: VIRGIL C. SUMMER NUCLEAR STATION, UNIT 1 (VCSNS) - REQUEST FOR ADDITIONAL INFORMATION (RAI) ON SURVEILLANDCE REQUIREMENTS (TAC NO. ME5011)

Dear Mr. Gatlin:

By letter dated November 11, 2010, the South Carolina Electric & Gas Company (SCE&G) submitted a license amendment request to revise the Technical Specifications in Appendix A to Facility Operating License Number NPF-12 for the Virgil C. Summer Nuclear Station, Unit 1.

SCE&G provided additional clarifying information in its letter dated June 16, 2011. The staff has reviewed the amendment request and the information in the June 16, 2011, letter and requests additional information, as stated in the Enclosure.

We request that a response be provided within 30 days of the date of this letter.

Sincerely, IRA!

Robert Martin, Senior Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-395

Enclosure:

RAI cc w/encl: Distribution via Listserv DISTRIBUTION PUBLIC LPL2-1 RJF RidsAcrsAcnw_MailCTR Resource RidsNrrDorlDpr Resource RidsNrrDorlLpl2-1 Resource RidsRgn2MailCenter Resource RidsNrrLASFigueroa RidsOgcRp Resource RidsNrrDe Resource GMatharu, NRR RMathew, NRR RidsNrrPMSummer Resource ADAMS Accession N0.: ML12068A424 *b)yemal OFFICE LPL2-1/PM LPL2-1/LA NRRJEEEB/BC LPL2-1/BC LPL2-1/PM NSaigado NAME RMartin SFigueroa JAnderson" RMartin I(VSreenivas for)

DATE 03/09/12 03/09112 111 03/09/12 03/13/12 OFFICIAL RECORD COPY