ML14043A006

First Round of Requests for Additional Information Regarding License Amendment Request Pursuant to 10 CFR 50.90: Maximum Extended Load Line Limit Analysis Plus (Mella+)

ML14043A006
Person / Time
Site:	Nine Mile Point
Issue date:	02/20/2014
From:	Bhalchandra Vaidya Plant Licensing Branch 1
To:	Costanzo C Nine Mile Point
Vaidya B, NRR/DORL/LPL1-1, 415-3308
References
TAC MF3056
Download: ML14043A006 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 February 20, 2014 Mr. Christopher Costanzo Vice President Nine Mile Point Nine Mile Point Nuclear Station, LLC P. 0. Box 63 Lycoming, NY 13093

SUBJECT:

NINE MILE POINT NUCLEAR STATION, UNIT NO.2- FIRST ROUND OF REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST PURSUANT TO 10 CFR 50.90: MAXIMUM EXTENDED LOAD LINE LIMIT ANALYSIS PLUS (MELLLA+) (TAC NO. MF3056)

Dear Mr. Costanzo:

By letter dated November 1, 2013 (Agencywide Document Access and Management System (ADAMS) Package Accession No. ML13316B090), as supplemented by letter dated January 21, 2014 (ADAMS Accession No. ML14023A654), Nine Mile Point Nuclear Station, LLC (the licensee) submitted a license amendment request for Nine Mile Point Nuclear Station, Unit 2. The proposed amendment would (1) allow operation in the expanded Maximum Extended Load Line Limit Analysis Plus (MELLLA+) domain; (2) use of the Detect and Suppress Solution - Confirmation Density (DSS-CD) stability solution, (3) use of the TRACG04 analysis code; (4) increase the isotopic enrichment of boron-1 0 in the sodium pentaborate solution used to prepare the neutron absorber solution in the Standby Liquid Control System (SLS); and (5) increase the Safety Limit Minimum Critical Power Ratio (SLMCPR) for two recirculation loops in operation.

The Nuclear Regulatory Commission (NRC) staff has reviewed the information provided in your submission and has determined that additional information is needed to complete its review.

The draft request for additional information (RAI) was transmitted to you by e-mail dated January 31, 2014 (ADAMS Accession No. ML14031A178). In the telephone conversation with your staff, Mr. Kenneth Kristensen, on February 11, 2014, your staff committed your response to these RAis by March 10, 2014.

The NRC staff's final version of the RAI is provided in the enclosure to this letter.

Sincerely,

~d-~

~

Bhalchandra Vaidya, Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-41 0

Enclosure:

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

FIRST ROUND REQUEST FOR ADDITIONAL INFORMATION RELATED TO LICENSE AMENDMENT REQUEST RE: MAXIMUM EXTENDED LOAD LINE LIMIT ANALYSIS PLUS CONSTELLATION ENERGY NINE MILE POINT NUCLEAR STATION, UNIT 2 By letter dated November 1, 2013 (Agencywide Document Access and Management System (ADAMS) Package Accession No. ML133168090), Constellation Energy (the licensee) submitted a license amendment request for maximum extended load line limit analysis plus (MELLLA+). The proposed amendment request would allow operation in the expanded MELLLA+ domain.

Upon review of Attachment 10 (ADAMS Accession No. ML133168107) to the submittal titled "Safety Analysis Report for Nine Mile Point Unit 2 Maximum Extended Load Line Limit Analysis Plus" (ADAMS Accession No. ML133168113), the staff has the following requests for additional information:

SRXB RAI1:

Section 9.3.3 of Attachment 10 states that zirconium credit will be used in the Shumway correlation. The staff is aware of the zirconium data described in letter dated September 9, 2013 (ADAMS Accession No. ML13253A105) from GE Hitachi Nuclear Energy to the NRC staff.

(a) Fresh fuel has little or no oxide at the start of the transient and the fresh fuel is often in the more reactive part of the core; therefore, it is the data of interest.

Figure 6 of the September 9, 2013 letter has many data sets displayed together on it. Provide a plot showing clean zirconium separate from all the other data including SS, lnconel, zirconium oxide and any data that would be expected to have oxidized zirconium.

(b) In the September 9, 2013 letter, much of the Hoffman (FKZ) data that has a rapid cooling rate early in the experiment may have been incorrectly interpreted as a quench. A closer examination of the data shows this initial cooling was due to startup of the test and that quench occurred much later at significantly lower temperatures. In addition, because of high temperatures during the tests and pre-conditioning of the rods, the rods are likely to have thick oxide layer thicknesses that are not representative of fuel in a commercial reactor undergoing an Anticipated Transient without Scram with Instability (ATWS-1) event. Provide a plot showing the data considered valid by the licensee for justifying Shumway as implemented in TRACG for the intended application (e.g. ATWS-1 under MELLLA+). Also provide textual justification to support the choice of the selected data and exclusion of the other data, focusing on comparing the applicable test conditions to the plant application conditions to support a conclusion that the data is applicable.

Enclosure

SRXB RAI2:

Section 9.3.3 of Attachment 10 states:

The plant-specific A TWS stability calculation was performed using the NRC-approved neutronic and thermal-hydraulic codes ... TRACG04.

An error in the code was corrected by letter from GE Hitachi Nuclear Energy to the staff dated October 15, 2013 titled "Updated TRACG Quench Front Model Description and Qualification", which is currently under staff review. In the October 15, 2013 letter, GE noted:

The quench front model has been updated to correct an error in the quench front heat transfer coefficient for bottom reflooding, and to better capture the heat transfer ahead of and behind the quench front.

Please clarify which quench model is being used in the application.

ML14023A654), Nine Mile Point Nuclear Station, LLC (the licensee) submitted a license amendment request for Nine Mile Point Nuclear Station, Unit 2. The proposed amendment would (1) allow operation in the expanded Maximum Extended Load Line Limit Analysis Plus (MELLLA+) domain; (2) use of the Detect and Suppress Solution - Confirmation Density (DSS-CD) stability solution, (3) use of the TRACG04 analysis code; (4) increase the isotopic enrichment of boron-10 in the sodium pentaborate solution used to prepare the neutron absorber solution in the Standby Liquid Control System (SLS); and (5) increase the Safety Limit Minimum Critical Power Ratio (SLMCPR) for two recirculation loops in operation.

The Nuclear Regulatory Commission (NRC) staff has reviewed the information provided in your submission and has determined that additional information is needed to complete its review.

The draft request for additional information (RAI) was transmitted to you by e-mail dated January 31, 2014 (ADAMS Accession No. ML14031A178). In the telephone conversation with your staff, Mr. Kenneth Kristensen, on February 11, 2014, your staff committed your response to these RAis by March 10, 2014.

The NRC staff's final version of the RAI is provided in the enclosure to this letter.

Sincerely, Ira/

Bhalchandra Vaidya, Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-41 0

Enclosure:

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

PUBLIC LPL 1-1 R/F RidsNrrDssStsb Resource RidsNrrDorllpl1-1 Resource RidsNrrLAKGoldstein Resource RidsNrrPMNineMilePoint Resource RidsRgn1 MaiiCenter Resource RidsAcrsAcnw_MaiiCTR Resource RidsNrrDssSrxb Resource RidsNrrDssSnpb Resource RidsNrrDssEicb Resource RidsNrrDssScvb Resource DSchroeder, Region 1 ADAMS Accession No.: ML14043A006 (*)Transmitted by memo dated 01/22/2014 OFFICE NRR/LPL 1-1\PM NRR/LPL 1-1\LA NRR/SRXB/BC(*) NRR/LPL 1-1/BC NRR/LPL 1-1\PM NAME BVaidya KGoldstein CJackson BBeasley BVaidya DATE 02/12114 02/12/14 01/22/14 02/19/14 02/20/14