ML14225A222

Nine Mile Point, Unit 2, MF4559, Request for Additional Information Submittal of Post EPU Steam Dryer Inspection Results in Accordance with Operating License Condition 2.C.(20)(f) and 2.C.(20)(g)

ML14225A222
Person / Time
Site:	Nine Mile Point
Issue date:	08/13/2014
From:	Bhalchandra Vaidya Plant Licensing Branch 1
To:	Darling T H, Kristensen K J, Varga B T Constellation Energy Nuclear Group, Nine Mile Point
Vaidya B K, NRR/DORL/LPL1-1, 415-3308
References
TAC MF4559
Download: ML14225A222 (1)

Text

From: Vaidya, Bhalchandra Sent: Wednesday, August 13, 2014 10:47 AM To: Darling, Theresa H (Theresa.Darling@cengllc.com); Kristensen, Kenneth J (Kenneth.Kristensen@cengllc.com); Varga, Brandon T:(NMP) <brandon.varga@exeloncorp.com>

(brandon.varga@exeloncorp.com); Loomis, Thomas R:(GenCo-Nuc)

(thomas.loomis@exeloncorp.com)

Cc: Li, Yong; Basavaraju, Chakrapani; Beasley, Benjamin

Subject:

Request for Additional Information NMP2, MF4559, Submittal of Post EPU Steam Dryer Inspection Results in Accordance with Operating License Condition 2.C.(20)(f) and 2.C.(20)(g)

SUBJECT:

Request for Additional Information, Nine Mile Point Unit 2, Submittal of Post Extended Power Uprate Steam Dryer Inspection Results in Accordance with Operating License Condition 2.C.(20)(f) and 2.C.(20)(g) (MF4559).

By letter dated July 28, 2014 (Agencywide Document Access and Management System (ADAMS) Accession No. ML14216A347), Nine Mile Point Nuclear Station, LLC (the Licensee) submitted the Post Extended Power Uprate (EPU) Steam Dryer Inspection Results in Accordance with Operating License Condition 2.C.(20)(f) and 2.C.(20)(g).

The Nuclear Regulatory Commission (NRC) staff has reviewed the information provided in your LAR and has determined that additional information is needed to complete its review. The NRC staff's DRAFT request for additional information (RAI) is provided below.

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REQUEST FOR ADDITIONAL INFORMATION (RAI) EXELON GENERATION COMPANY NINE MILE POINT NUCLEAR STATION, UNIT 2 (NMP2) POST EXTENDED POWER UPRATE STEAM DRYER (SD) INSPECTION RESULTS AFTER FIRST REFUELING OUTAGE (RFO) DOCKET NO. 50-410 (TAC NO. MF4559)

Reference:

1. Letter From Paul M. Swift, Director of Site Engineering, Nine Mile Point Nuclear Power Station, to U. S. Nuclear Regulatory Commission, Document Control Desk, "Extended Power Uprate Steam Dryer Inspection Results in Accordance with Operating License Condition 2.C.(20)(f) and 2.C.(20)(g)," July 28, 2014. (ML14216A347)

SD-First RFO Post EPU-RAI-1

Section 4.0 of Attachment to Ref. 1 refers to resolution of Acoustic circuit Model (ACM) version 4.1 computer software Vendor Non-Conformance NC-0343, and a Corrective Action Program (CP-2013-008411. It was also mentioned that that the ACM version 4.1 computer software used for the NMP2 steam dryer evaluation was run with an option activated that was not consistent with the ACM version 4.1 computer software used to define the ACM version 4.1 computer software benchmark bias and uncertainties. The licensee is requested to provide the following additional information: (a) A copy of NC-0343 (b) A copy of CP-2013-008411 (c) Describe the details on the option activated in the ACM version 4.1 computer software that was not consistent with the ACM version 4.1 computer software benchmark.

SD-First RFO Post EPU-RAI-2

It was mentioned in Section 4.0 of Attachment to Ref. 1 that the steam dryer was modified in April 2014 by adding a bracket to the center closure plate high stress location to eliminate the end plate vibration mode. Please provide the following additional information: (a) A sketch of the local area of the steam dryer before and after the addition of the stiffener bracket. (b) Details of the closure plate vibration mode (natural frequency) that was eliminated by the addition of the stiffener bracket. Also, summarize the minimum alternating stress ratio (MASR) of the dryer before and after the installation of the stiffener bracket.

SD-First RFO Post EPU-RAI-3

As a result of the ACM version 4.1 computer software non-conformance, it was mentioned in Section 4.0 of Attachment to Ref. 1 that the steam dryer loads were corrected using ACM version 4.1R computer software, the steam dryer evaluation was re-performed, and three new reports were generated. Please provide the following additional information:

(a) Continuum Dynamics Inc. (CDI) Report No.14-09P "Acoustic and Low Frequency Hydrodynamic Loads at 115% CLTP Target Power Level on Nine Mile Point Unit 2 Steam Dryer to 250 Hz Using ACM 4.1R" (b) CDI Report No.14-08P "Stress Re-Evaluation of Nine Mile Point Unit 2 Steam Dryer at 115% Current Licensed Thermal Power (CLTP)"

(c) CDI Report No.14-04P "Computation of the Cumulative Usage Factor for the 115% stress Re-Evaluation of Nine Mile Point Unit 2 Steam Dryer at 115% CLTP power level at Nine Mile Point Unit 2 with the Inboard Reactor Core Isolation Cooling (RCIC) valve closed"

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The NRC staff would like to receive the responses to the RAIs by COB, September 15, 2014. Please contact me, ASAP, to schedule a tele

-conference between the licensee and the NRC staff to ensure that the licensee clearly understands the RAIs and also, to obtain a firm commitment/ confirmation from the licensee for the Responses to these RAIs.

Please contact me, if you have any questions.

Thanks, Bhalchandra K. Vaidya Licensing Project Manager NRC/NRR/DORL/LPL1-1 (301)-415-3308 (O) bhalchandra.vaidya@nrc.gov