ML17291A710

NRR E-mail Capture - Request for Additional Information - License Amendment Request (LAR) for Transition to Westinghouse Core Design and Safety Analyses Including Adoption of Alternative Source Term

ML17291A710
Person / Time
Site:	Wolf Creek
Issue date:	10/17/2017
From:	Balwant Singal Plant Licensing Branch IV
To:	Muilenburg W Wolf Creek
References
EPID No.: L-2017-LLA-0211, MF9307
Download: ML17291A710 (4)

Text

NRR-PMDAPEm Resource From: Singal, Balwant Sent: Tuesday, October 17, 2017 10:06 AM To: Muilenburg William T Cc: Alvarado, Rossnyev

Subject:

Request for Additional Information - License Amendment Request (LAR) for Transition to Westinghouse Core Design and Safety Analyses including Adoption of Alternative Source Term (CAC No. MF9307)

Attachments: MF9307-EICB-RAI.docx By letter dated January 17, 2017 (Agencywide Documents Access and Management System (ADAMS)

Accession No. ML17054C103, Package), as supplemented by letter dated May 4, 2017 (ADAMS Accession No. ML17130A915), Wolf Creek Nuclear Operating Corporation (WCNOC) submitted License Amendment Request (LAR) to transition to Westinghouse Core design and Safety Analyses (including adoption of Alternative Source Term) for Wolf Creek Generating Station (WCGS).

The U.S. Nuclear Regulatory Commission (NRC) staff is in the process of reviewing the subject LAR and has identified the need for additional information described in the attachment to this e-mail. Draft Request for Additional Information (RAI) was transmitted on October 6, 2017 and a clarification was held on October 16, 2017. It was agreed that WCNOC will provide response to these RAIs within 30 days from the date of this e-mail. Please treat this e-mail as transmittal of official RAIs.

Please note that several technical branches have been assigned for review of this LAR and this is only a partial request.

1

Hearing Identifier: NRR_PMDA Email Number: 3777 Mail Envelope Properties (6bf3d20d5735404aba930e547cfccee7)

Subject:

Request for Additional Information - License Amendment Request (LAR) for Transition to Westinghouse Core Design and Safety Analyses including Adoption of Alternative Source Term (CAC No. MF9307)

Sent Date: 10/17/2017 10:05:35 AM Received Date: 10/17/2017 10:05:00 AM From: Singal, Balwant Created By: Balwant.Singal@nrc.gov Recipients:

"Alvarado, Rossnyev" <Rossnyev.Alvarado@nrc.gov>

Tracking Status: None "Muilenburg William T" <wimuile@WCNOC.com>

Tracking Status: None Post Office: HQPWMSMRS05.nrc.gov Files Size Date & Time MESSAGE 1075 10/17/2017 10:05:00 AM MF9307-EICB-RAI.docx 27964 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received: ZZZ

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST FOR TRANSITION TO WESTINGHOUSE CORE DESIGN AND SAFETY ANALYSIS INCLUDING ADOPTION OF ALTERNATIVE SOURCE TERM WOLF CREEK GENERATING STATION (CAC NO. MF9307)

By letter dated January 17, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML17054C103), as supplemented by letters dated March 22 and May 4, 2017 (ADAMS Accession Nos. ML17088A635 and ML17130A915, respectively), Wolf Creek Nuclear Operating Corporation (WCNOC, the licensee), submitted a license amendment request (LAR) for the Wolf Creek Generating Station (WCGS) to transition to Westinghouse Core Design and Safety Analysis, including adoption of the alternative source term (AST).

The proposed LAR would replace the WCNOC methodology for performing core design, non-loss-of-coolant-accident (non-LOCA) and LOCA safety analyses to the standard Westinghouse methodologies for performing these analyses, and associated technical specification (TS) changes. The proposed amendment would also revise WCGS TSs and the Updated Safety Analysis Report Chapter 15 radiological consequence analyses using an updated accident source term consistent with Title 10 of the Code of Federal Regulations (10 CFR), Section 50.67, Accident source term.

The U.S. Nuclear Regulatory Commission (NRC) staff requests for the following additional information for completing the review of the proposed LAR. Please note that this request for additional information (RAI) is related to the review by Instrumentation and Controls Branch and is in addition to the RAIs issued by e-mail dated June 14, 2017 (ADAMS Accession No. ML17166A038) and WCNOC response by letter dated July 13, 2017 (ADAMS Accession No. ML17200C939).

Regulatory Basis for the Request NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor] Edition, Chapter 7, Instrumentation and Controls, August 2016 (ADAMS Accession No. ML16020A049), defines the acceptance criteria for this review. Standard Review Plan Chapter 7 addresses the requirements for instrumentation and control systems in light-water nuclear power plants. The regulatory requirements and guidance which the NRC staff considered in its review are as follows:

• 10 CFR 50.36(c)(1)(ii)(A) requires in part that where a limiting safety system setting is specified for a variable on which a safety limit has been placed, the setting must be so chosen that automatic protective action will correct the abnormal situation before a safety limit is exceeded. If, during operation, it is determined that the automatic safety system does not function as required, the licensee shall take appropriate action, which may include shutting down the reactor.

• 10 CFR 50.36 (c)(2)(i) requires that the TSs include limiting conditions for operation (LCOs) for equipment required to ensure safe operation of the facility. When an LCO for operation of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TSs until the condition can be met.

• 10 CFR 50.36 (c)(3) states TS Surveillance Requirements (SRs) relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the

limiting conditions for operation will be met. 10 CFR 50.36, Technical specifications, states, Each applicant for a license authorizing operation of a production or utilization facility shall include in his application proposed technical specifications in accordance with the requirements of this section. Specifically, 10 CFR 50.36(c)(2)(ii) sets forth four criteria to be used in determining whether a limiting condition for operation is required to be included in the TS.

• 10 CFR 50.55a(h) requires that the protection systems must meet the requirements in Institute of Electrical and Electronics Engineers (IEEE) Std. 279-1968, "Proposed IEEE Criteria for Nuclear Power Plant Protection Systems," or the requirements in IEEE Std. 279-1971, "Criteria for Protection Systems for Nuclear Power Generating Stations," or the requirements in IEEE Std. 603-1991, "Criteria for Safety Systems for Nuclear Power Generating Stations, and the correction sheet dated January 30, 1995.

EICB-RAI 3

a. In the LAR, Enclosure IV, WCNOC requested to add Surveillance Requirement (SR) 3.3.7.6 to TS 3.3.7, Control Room Emergency Ventilation System (CREVS) Actuation Instrumentation, Function 2 (Automatic Actuation Logic and Actuation Relays and Function 3 (Control Room Radiation - Control Room Air Intakes) of Table 3.3.7-1.

Enclosure IV of the LAR identifies the new SR, and provides the basis for adding it. In particular, WCNOC is requesting to add this SR to ensure that the time delay used in the AST model is bounded. Enclosure IV states that the acceptance criteria for the CREVS actuation instrumentation is 60 seconds.

EICB-RAI 3 Please provide additional information, such as calculations, to support the proposed CREVS actuation instrumentation response criteria.

The proposed SR requires verification of the Control Room Ventilation Isolation Engineered Safeguard Features (ESF) RESPONSE TIMES are within limits. The TS does not include the acceptance criteria for the CREVS actuation system.

EICB-RAI 3 Please explain how operators will determine if the acceptance criteria to determine that the response time is within limits?

The proposed SR also includes a note to exclude the radiation monitor detectors from ESF response time testing. This document states that this note is necessary because of the difficulty associated with generating an appropriate radiation monitor detector input signal.

EICB-RAI 3 Please explain why there is difficulty associated with generating an appropriate radiation monitor detector input signal. Also, please justify that the exclusion of radiation monitoring response time will provide an accurate measure of ESF response times.

b. In the LAR, Enclosure VI, WCNOC explained that they will implement a design modification to supply the CREVS control room isolation dampers with battery power. WCNOC noted that this modification is necessary to support implementation of AST.

EICB-RAI 4 - Please describe the logic to isolate the CREVS. This description should include a discussion of how and when battery backed power will insure CREVS isolation.