ML18037B075
| ML18037B075 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 01/30/2018 |
| From: | Michael Wentzel Plant Licensing Branch II |
| To: | Hanek O Florida Power & Light Co |
| References | |
| L-2017-0423 | |
| Download: ML18037B075 (3) | |
Text
1 NRR-DMPSPEm Resource From:
Wentzel, Michael Sent:
Tuesday, January 30, 2018 12:56 PM To:
Hanek, Olga Cc:
robert.hess@fpl.com; Mack, Jarrett
Subject:
Draft Request for Additional Information - Turkey Point 3 LAR 256 (EPID L-2017-0423)
Good afternoon Olga, By application dated December 18, 2017 (Agencywide Documents and Access Management System (ADAMS)
Accession No. ML17353A492), Florida Power & Light Company (FPL, the licensee) submitted License Amendment Request (LAR) No. 256 for Turkey Point Nuclear Generating Unit No. 3 (Turkey Point). The proposed amendment would revise the Technical Specifications (TSs) to allow for a one-time extension of the Completion Time for the Containment Spray (CS) system from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days.
The U.S. Nuclear Regulatory Commissions (NRCs) Probabilistic Risk Assessment Licensing Branch A (APLA) staff reviewed the application and identified areas where it needs additional information to support its review. The draft request for additional information (RAI) is provided below.
Please let me know by February 2, 2018, if a clarification call is needed and if the draft RAI contains any proprietary information. If a clarification call is not needed, please let me know if FPL can respond to the RAI by February 13, 2018.
APLA RAI 01: PRA CAPABILITY AND INSIGHTS Section 2.3, Evaluation for Risk Impact, of Regulatory Guide (RG) 1.177, Revision 1, An Approach for Plant-Specific, Risk-Informed Decision-making: Technical Specifications, provides a detailed approach for evaluating Technical Specification (TS) changes. In the three-tiered approach, Tier 1 discusses two aspects that need to be considered when assessing the impact of the TS change on core damage frequency (CDF),
incremental conditional core damage probability (ICCDP), large early release frequency (LERF), and incremental conditional large early release probability (ICLERP). The two aspects included (1) the validity of the probabilistic risk assessment (PRA) and (2) the PRA insights and findings. To address the two aspects and confirm the validity of the risk estimates provided in Section 3.3.1.4 of your December 18, 2017, request, provide the following additional information:
- a. Confirm that the peer review history for the Internal Events (IE) and Internal Floods (IF) PRA models used to perform the risk evaluation in the licensing amendment request (LAR) dated December 18, 2017, are the same as those described in the risk-informed inservice inspection LAR dated January 14 2016 (ADAMS Accession No. ML16033A355) and approved by the NRC staff in the safety evaluation dated October 26, 2017 (ADAMS Accession No. ML16293A778). If not, provide the current review history up to the December 18, 2017, LAR.
- b. The CS system generally supports long term containment overpressure protection and fission product removal to reduce release fractions. As such, failure of the CS system generally does not contribute to CDF and LERF. Section 3.3.1.1, Results, of the December 18, 2017, LAR provides the total delta CDF and delta LERF results. The results indicate a very small increase in CDF and correspondingly a very small increase in LERF due to extending the completion time to 14 days for one CS train inoperable.
- 1. Provide discussion of PRA insights that justify the very small increases for CDF and LERF as a result of the failure of one train of CS and,
2
- 2. Identify any open IE and IF finding-level facts and observations (F&Os) that might affect the CDF and LERF estimates where the delta CDF and delta LERF values will no longer meet the RG 1.177 risk metrics. Specifically, steam generator tube rupture and interfacing system loss-of-coolant accident are two primary accident initiators which contribute to LERF and were identified in the risk-informed inservice inspection LAR as remaining open and unresolved. For any F&Os identified, provide a disposition that assesses any potential impact as it pertains to the request for a one time extension of the completion time for one inoperable train of CS.
APLA RAI 02 - Tier 2: AVOIDANCE OF RISK-SIGNIFICANT PLANT CONFIGURATIONS RG 1.177, Revision 1, identifies a three-tiered approach for the licensees evaluation of the risk associated with a proposed Completion Time (CT) TS change.
In its December 18, 2017, submittal, the licensee relies on its configuration risk management program (CRMP) without performing any evaluations (qualitative or quantitative) to identify potential risk-significant plant configurations for the proposed one-time CT extension. This reliance on the CRMP is more appropriate for the Tier 3 evaluation, which ensures that adequate programs and procedures are in place for identifying risk-significant plant configurations and taking appropriate actions to avoid such configurations.
Whereas the Tier 3 evaluation ensures the CRMP is adequate when maintenance is about to commence, the Tier 2 evaluation is meant to be an early evaluation to identify and preclude potentially high-risk plant configurations that could result if equipment, in addition to that associated with the proposed license amendment, are taken out of service simultaneously, or if other risk-significant operational factors, such as concurrent system or equipment testing, are also involved.
To distinguish between Tier 2 and Tier 3 reliance on the CRMP, and address Tier 2 in its entirety, identify for the subject one-time CT extension, any high-risk plant configurations that may occur and the compensatory measures the licensee is implementing to ensure these configurations do not occur during the one-time CT extension.
Hearing Identifier:
NRR_DMPS Email Number:
148 Mail Envelope Properties (Michael.Wentzel@nrc.gov20180130125600)
Subject:
Draft Request for Additional Information - Turkey Point 3 LAR 256 (EPID L-2017-0423)
Sent Date:
1/30/2018 12:56:13 PM Received Date:
1/30/2018 12:56:00 PM From:
Wentzel, Michael Created By:
Michael.Wentzel@nrc.gov Recipients:
"robert.hess@fpl.com" <robert.hess@fpl.com>
Tracking Status: None "Mack, Jarrett" <Jarrett.Mack@fpl.com>
Tracking Status: None "Hanek, Olga" <Olga.Hanek@fpl.com>
Tracking Status: None Post Office:
Files Size Date & Time MESSAGE 5545 1/30/2018 12:56:00 PM Options Priority:
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