ML14324A637

Request for Additional Information Regarding License Amendment Request to Increase Voltage Limit for Diesel Generator Load Rejection Surveillance Requirement

ML14324A637
Person / Time
Site:	Seabrook
Issue date:	11/24/2014
From:	John Lamb Plant Licensing Branch 1
To:	Dean Curtland, Ossing M NextEra Energy Seabrook
John Lamb, NRR/DORL
References
TAC MF4578
Download: ML14324A637 (5)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 November 24, 2014 Mr. Dean Curtland, Site Vice President c/o Michael Ossing Seabrook Station NextEra Energy Seabrook, LLC P.O. Box 300 Seabrook, NH 03874

SUBJECT:

SEABROOK STATION, UNIT 1 -REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO INCREASE VOLTAGE LIMIT FOR DIESEL GENERATOR LOAD REJECTION SURVEILLANCE REQUIREMENT (TAC NO. MF4578)

Dear Mr. Curtland:

By letter dated July 24, 2014 (Agencywide Documents Access and Management System Accession Number ML14209A918), NextEra Seabrook, LLC (NextEra or the licensee) requested an amendment to Facility Operating License Number NPF-86 for the Seabrook Station, Unit 1 (Seabrook). The proposed license amendment would revise Technical Specification (TS) 3.8.1.1, "A. C. Sources- Operating," and TS 1.0, "Definitions." Specifically, the proposed changes would: (1) increase the voltage limit for a full load rejection test of the emergency diesel generator specified in the TS surveillance requirement (SR) 4.8.1.1.2.f.3; and (2) revise the TS 1. 21 definition of "Operable - Operability."

The U.S. Nuclear Regulatory Commission (NRC) staff has determined that additional information is required to complete its review. The NRC staff's request for additional information (RAI) is contained in the enclosure.

A draft of these questions was previously sent to Mr. Mike Ossing of your staff on November 17, 2014, with an opportunity to have a teleconference to ensure that NextEra understood the questions and their regulatory basis, as well as to verify that the information was not previously docketed.

A conference call was held on November 19, 2014, and Mr. Ossing of your staff agreed that NextEra would respond to the RAI within 60 days of the date of this letter. Please note that if you do not respond to the RAI by the agreed upon date, the NRC staff may reject your amendment under the provisions of Title 10 of the Code of Federal Regulations, Section 2.1 08, "Denial of application for failure to supply information."

D. Curtland If you have any questions, please contact me at (301) 415-3100.

n G. Lamb, Senior Project Manager ant Licensing Branch 1-2 ivision of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-443

Enclosure:

Request for Additional Information cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO INCREASE VOLTAGE LIMIT FOR DIESEL GENERATOR LOAD REJECTION SURVEILLANCE REQUIREMENT (TAC NO. MF4578)

NEXTERA ENERGY SEABROOK, LLC.

SEABROOK STATION, UNIT 1 DOCKET NUMBER 50-443 1.0 SCOPE By letter dated July 24, 2014 (Agencywide Documents Access and Management System Accession Number ML14209A918), NextEra Seabrook, LLC (NextEra or the licensee) requested an amendment to Facility Operating License Number NPF-86 for the Seabrook Station, Unit 1 (Seabrook). The proposed license amendment would revise Technical Specification (TS} 3.8.1.1, "A.C. Sources- Operating," and TS 1.0, "Definitions." Specifically, the proposed changes would: (1) increase the voltage limit for a full load rejection test of the emergency diesel generator specified in the TS surveillance requirement (SR) 4.8.1.1.2.f.3; and (2) revise the TS 1.21 definition of "Operable- Operability."

The U.S. Nuclear Regulatory Commission (NRC) staff has determined that additional information is required to complete its review.

2.0 REQUEST FOR ADDITIONAL INFORMATION

1. On page 1 of the license amendment request (LAR), the licensee states: 'When an EDG [emergency diesel generator] is operated in parallel with the grid for the purpose of the full load rejection test, the emergency bus voltage is further increased as excitation is adjusted to meet the required VAR [volt-ampere reactive] loading."

Please provide the value of the required VAR loading considered for the full load rejection test and the basis for that value. Since the overvoltage limit is also dependent on the VAR loading, please explain why the VAR loading is not considered as part of SR 4.8.1.1.2.1.3.

2. On pages 2 and 3 of the LAR, the licensee states: "NextEra evaluated why previous voltage excursions on April24, 2005, and December 7, 2005, on EDG-1B did not affect its ability to perform its safety function of providing backup power to the emergency bus. The subject voltage excursions lasted approximately 4.7 minutes and 5.3 minutes. The evaluation concluded that a voltage of about 6000 volts, although undesirable, will not damage the generator or exciter components."

Enclosure

Please provide the peak voltages experienced during the previous voltage excursions on EDG-1 Bon April24, 2004, and December 7, 2005, and explain the reasons for these voltage excursions.

3. Please provide a copy of the single line diagram showing the connection of one of the EDGs to an emergency bus and associated protections (protective relays, etc.) provided for the EDG.

ML14324A637 via e-mail **via memo OFFICE LPL 1-2/PM LPL 1-2/LA* EEEB/BC** LPL 1-2/BC LPL 1-2/PM MKhanna NAME Jlamb ABaxter JZimmerman Jlamb (REnnis for)

DATE 11/21/14 11/24/14 11/14/14 11/24/14 11/24/14