NRC-23-0072, Clarification for RAI Response from 10-16-23 Phone Call Regarding Exigent License Amendment Request for Exigent License Amendment Request for Technical Specification 3.8.1, AC Sources - Operating - in Relation to Mechanical Draft Cool
| ML23291A143 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 10/18/2023 |
| From: | Frank E DTE Electric Company |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| NRC-23-0072 | |
| Download: ML23291A143 (1) | |
Text
October 18, 2023 NRC-23-0072 DTE Electric Company 6400 N. Dixie Highway Newport, MI 48166 DTE 10 CFR 50.90 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001 Fermi 2 Power Plant NRC Docket No. 50-341 NRC License No. NPF-43
Subject:
Clarification for RAI Response from 10-16-23 Phone Call Regarding Exigent License Amendment Request for "Exigent License Amendment Request for Technical Specification 3.8.1, "AC Sources - Operating" - In Relation to Mechanical Draft Cooling Tower (MDCT) Repairs
References:
- 1) DTE Letter NRC-23-0068, "Exigent License Amendment Request for Technical Specification 3.8.1, "AC Sources - Operating" dated September 28, 2023. (ML23271Al 88) (EPID L-2023-LLA-0134)
- 2) NRC E-mail Capture, "Request for Additional Information for Changes to TS 3.8.1, "AC Sources - Operating," dated October 10, 2023.
- 3) DTE Letter NRC-23-0071, "Response to Request for Additional Information (RAI) for Exigent License Amendment Request for Revision of Technical Specification (TS) 3.8.1 "AC Sources - Operating" dated October 13, 2023. (ML23286Al 12)
- 4) NRC Phone Call, "Request for Clarification Regarding Changes to TS 3.8.1, "AC Sources - Operating," dated October 16, 2023.
In Reference 1, DTE Electric Company (DTE) submitted an Exigent License Amendment Request to revise the Fermi 2 Technical Specifications (TS).
In Reference 2, an email from Mr. Surinder Arora to Mr. Eric Frank dated October 10, 2023, the NRC sent DTE a Request for Additional Information (RAI) regarding the LAR.
In Reference 3, DTE Electric Company (DTE) provided the responses requested in Reference 2.
In Reference 4, the NRC requested clarification regarding the responses provided in Reference
- 3.
The clarification requested in Reference 4 is outlined in the enclosure of this letter.
USNRC NRC-23-0072 Page2 No new commitments are being made in this submittal.
Should you have any questions or require additional information, please contact me at (734) 586-4772.
Enclosure:
RAJ Clarification Response cc: NRC Project Manager NRC Resident Office Regional Administrator, Region III Sincerely, Eric Frank Manager - Nuclear Licensing Michigan Department of Environment, Great Lakes, and Energy
Enclosure to NRC-23-0072 Fermi 2 NRC Docket No. 50-341 Operating License No. NPF-43 RAI Clarification Response
Enclosure to NRC-23-0072 Page 1 Areas Needing Clarification for NRC:
- 1. Describe the configuration and capabilities of the Division I Emergency Diesel Generator (EDG) Service Water systems (EDGSW) during the period of maintenance for the Division I Mechanical Draft Cooling Towers (MDCT).
The EDGSW for EDGs 11 and 12, although inoperable due to TS 3.7.2 (because of one inoperable MDCT), will remain in standby, functional, and capable of auto-start if needed and will provide cooling if the associated EDG auto-starts. The Ultimate Heat Sink (UHS) will continue to provide cooling water to the EDGSW system during this repair.
The other Division I MDCT (A or C) will still be in standby, functional, and capable of providing cooling to the UHS, while the other MDCT is being repaired.
- 2. Describe the configuration, capacities, and capabilities of the Division II Safety Systems to support the response to Loss of Of/site Power (LOOP) and/or Loss of Coolant Accident (LOCA), including the Division II EDGs and Electrical Systems. This includes any compensatory measures that would be in place to ensure their availability.
The configuration, capacities, and capabilities of all Division II Safety Systems, as described in the Fermi 2 UFSAR Chapter 6 "Engineered Safety Features" (ML22325A130) and Chapter 8 "Electric Power" (ML22325A125), will remain operable and able to support a LOOP and/or LOCA. Repair activities on the Division I MDCT will not impact the configuration, capabilities, and capacities of the Division II Safety Systems. The Division II EDGs (13 & 14), including support systems, will remain operable, in standby and capable of supporting a LOOP and/or LOCA.
All compensatory measures are described in Section 3.3 ofNRC-23-0068 (ML23271A188) and will ensure that the Division II Safety Systems are protected and operable during the repair of the Division I MDCTs.
- 3. Discuss any additional alternate power supplies that may be available.
The alternate power supply used at Fermi 2 is discussed in the excerpt below from UFSAR Section 7.5.2.5.2 (ML22325A135). Additional information is included in that UFSAR section.
UFSAR Section 7.5.2.5.2 The alternative shutdown system consists of one of the four combustion turbine generators (CTGs), the standby feedwater (SBFW) system, a dedicated shutdown control panel and associated instrumentation, a Distributed Control System (DCS), and Division I portions of the following systems: RHR, RHRSW, emergency equipment cooling water (EECW), and
Enclosure to NRC-23-0072 Page2 emergency equipment service water (EESW). The dedicated shutdown panel is supplemented by local manual operator actions to achieve hot or cold shutdown.
The four CTGs (Subsection 8.2.1.2) are oil-fired turbine generators located onsite, remote from the fire areas of concern. The CTG 11-1 is used to provide emergency power when a fire occurs in the fire areas of concern, or on loss of offsite power should the EDGs be unavailable. CTG 11-1 has black start capability. The CTG starting diesel is located in an enclosed heated compartment and is equipped with a float tank, which provides an initial supply of warm fuel oil, to ensure its operability. Diesel fuel is maintained in the CTG Fuel Oil Tank with a fuel level maintained by plant procedures to ensure nominal fuel availability for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of operation for a single CTG unit at 10 MW load.
If CTG 11-1 is not available, either CTG 11-2, CTG 11-3 or CTG 11-4 (with AC starting motors) can be established on a standby basis as the black start power source for alternative shutdown power source using a standby starting diesel generator.
End of Enclosure