ML17019A053

Supplemental Information Needed for Acceptance of Requested Licensing Action Amendment to Reduce Steam Dome Pressure in Reactor Core Safety Limits

ML17019A053
Person / Time
Site:	Nine Mile Point
Issue date:	01/31/2017
From:	Marshall M Plant Licensing Branch 1
To:	Bryan Hanson Exelon Nuclear
Marshall, M NRR-DORL-LPL1 415-2871
References
CAC MF8942
Download: ML17019A053 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 January 31, 2017 Mr. Bryan C. Hanson President and Chief Nuclear Officer Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

NINE MILE POINT NUCLEAR STATION, UNIT 2 - SUPPLEMENTAL INFORMATION NEEDED FOR ACCEPTANCE OF REQUESTED LICENSING ACTION RE: AMENDMENT TO REDUCE STEAM DOME PRESSURE IN REACTOR CORE SAFETY LIMITS (CAC NO. MF8942)

Dear Mr. Hanson:

By letter dated December 13, 2016 (Agencywide Documents Access and Management System Accession No. ML16348A368), Exelon Generation Company, LLC (Exelon) submitted a license amendment request for the Nine Mile Point Nuclear Station, Unit 2 (NMP2). The proposed amendment would revise the NMP2 technical specification (TS) safety limit (SL) to increase the low pressure isolation setpoint allowable value, which will result in earlier main steam line isolation. The revised main steam line low pressure isolation capability and the revised SL are intended to ensure that NMP2 remains within the TS SLs in the event of a pressure regulator failure maximum demand transient. The purpose of this letter is to provide the results of the U.S. Nuclear Regulatory Commission (NRC) staff's acceptance review of this amendment request. The acceptance review was performed to determine if there is sufficient technical information in scope and depth to allow the NRC staff to complete its detailed technical review.

The acceptance review is also intended to identify whether the application has any readily apparent information insufficiencies in its characterization of the regulatory requirements or the licensing basis of the plant.

Consistent with Section 50. 90 of Title 10 of the Code of Federal Regulations ( 10 CFR), an amendment to the license (including the TSs) must fully describe the changes requested, and following as far as applicable, the form prescribed for original applications. Section 50.34 of 10 CFR addresses the content of technical information required. This section stipulates that the submittal address the design and operating characteristics, unusual or novel design features, and principal safety considerations.

The NRC staff has reviewed your application and concluded that the information delineated in the enclosure to this letter is necessary to enable the staff to make an independent assessment regarding the acceptability of the proposed amendment in terms of regulatory requirements and the protection of public health and safety and the environment.

In order to make the application complete, the NRC staff requests that Exelon supplement the application to address the information requested in the enclosure by February 17, 2017. This will enable the NRC staff to begin its detailed technical review. If the information responsive to the NRC staff's request is not received by the above date, the application will not be accepted for review pursuant to 10 CFR 2.101, and the NRC will cease its review activities associated

B. Hanson with the application. If the application is subsequently accepted for review, you will be advised of any further information needed to support the staff's detailed technical review by separate correspondence.

The information requested and associated timeframe in this letter were discussed with Mr. Ronald Reynolds of your staff on January 31, 2017.

If you have any questions, please contact me, at (301) 415-2871 or Michael.Marshall@nrc.gov.

Sincerely, Michael L. Marshall, Jr., Senior Project Manager Plant Licensing Branch 1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-41 O

Enclosure:

Supplemental Information Needed cc w/encl: Distribution via Listserv

SUPPLEMENTAL INFORMATION NEEDED AMENDMENT REQUEST TO REDUCE STEAM DOME PRESSURE IN REACTOR CORE SAFETY LIMITS EXELON GENERATION COMPANY. LLC NINE MILE POINT NUCLEAR STATION. UNIT 2 DOCKET NO. 50-410 By letter dated December 13, 2016 (Agencywide Documents Access and Management System Accession No. ML16348A368), Exelon Generating Company, LLC (the licensee) submitted a license amendment request for the Nine Mile Point Nuclear Station, Unit 2. The proposed amendment would reduce the steam dome pressure safety limit from 785 pounds per square inch gauge (psig) to 700 pounds per square inch absolute (psia) in Technical Specifications (TSs) 2.1.1.1 and 2.1.1.2, and increase the main steam line pressure low allowable value from

<:: 746 psig to<:: 814 psig in TS 3.3.6.1-1.

The U.S. Nuclear Regulatory Commission staff has reviewed the licensee's application and concluded that the following information associated with the calculation of instrument setpoint values is necessary to enable the staff to make an independent assessment regarding the acceptability of the proposed amendment in terms of the regulatory requirements for ensuring that instrument setpoints are initially within, and remain within, the TS limits.

The proposed amendment should include the following:

(1) Description of the methodology used for the calculation, including a listing of regulatory guidance and standards that the methodology conforms.

(2) Description of the assumptions or changes in assumptions for the calculation, including the bases for new or changed assumptions.

(3) Description of the types of errors (e.g., instrument errors, environmental errors (including harsh environments), electromagnetic interference/radio frequency interference errors, power supply errors, process errors, measurement and test errors, drift, etc.).

(4) Description of how the errors are combined to meet the setpoint methodology.

(5) Provide the calculated error for each loop device and the value of the total loop uncertainty (total loop error).

(6) Provide the values of as-left tolerance and as-found tolerance and how errors outside the acceptable range are handled.

Enclosure

B. Hanson

SUBJECT:

NINE MILE POINT NUCLEAR STATION, UNIT 2 - SUPPLEMENTAL INFORMATION NEEDED FOR ACCEPTANCE OF REQUESTED LICENSING ACTION RE: AMENDMENT TO REDUCE STEAM DOME PRESSURE IN REACTOR CORE SAFETY LIMITS (CAC NO. MF8942) DATED JANUARY 31, 2017 DISTRIBUTION:

PUBLIC LPL 1 R/F RidsACRS_MailCTR Resource RidsNrrDorl Resource RidsNrrDorlLpl1 Resource RidsNrrLALRonewicz Resource RidsNrrPMNineMilePoint Resource RidsRgn1 MailCenter Resource RidsNrrDssSrsb Resource RidsNrrDssSrxb Resource RidsNrrDeEicb Resource CTilton, NRR MRazzaque, NRR GSingh, NRR MLee, NRR ADAMS Accession Number: ML17019A053 OFFICE NRR/DORL/LPL 1/PM NRR/DORL/LPL 1/PM NRR/DORL/LPL 1/LA NAME MMarshall RGuzman LRonewicz DATE 1/23/2017 1/23/2017 1/23/2017 OFFICE NRR/DE/EICB/BC NRR/DORL/LPL 1/BC NRR/DORL/LPL 1/PM NAME MWaters SKoenick MMarshall DATE 1/26/2017 1/26/2017 1/31/2017 OFFICIAL RECORD COPY