ML24058A232

2/27/2024 E-mail from S. Sinha to R. Guzman P-8 Instrument Uncertainty in Support of LAR Framatome Gaia Fuel

ML24058A232
Person / Time
Site:	Millstone
Issue date:	02/27/2024
From:	Sinha S Dominion Energy Nuclear Connecticut
To:	Richard Guzman NRC/NRR/DORL/LPL1
References
EPID L-2023-LLA-0150
Download: ML24058A232 (1)

Text

From: Shayan.Sinha@dominionenergy.com To: Richard Guzman

Subject:

[External_Sender] RE: Millstone Power Station, Unit 3 - Acceptance Review Determination Re: LAR to Support the Implementation of Framatome GAIA Fuel (EPID L-2023-LLA-0150)

Date: Tuesday, February 27, 2024 8:34:18 AM

Rich, As part of development of the subject LAR, Dominion reviewed the uncertainty calculation with respect to the P-8 change. This review indicated that the 0.6% uncertainty is a function of the bistable, and is not a function of the setting of the bistable. Therefore, Dominion was able to confirm that the uncertainty remains valid and applicable at the lower power level.

Please let me know if you have any further questions or need any additional clarification.

Thanks, Shayan

From: Richard Guzman <Richard.Guzman@nrc.gov>

Sent: Thursday, February 15, 2024 6:44 PM To: Shayan Sinha (Services - 6) <Shayan.Sinha@dominionenergy.com>

Subject:

[EXTERNAL] RE: Millstone Power Station, Unit 3 - Acceptance Review Determination Re: LAR to Support the Implementation of Framatome GAIA Fuel (EPID L-2023-LLA-0150)

Shayan,

As I mentioned today, the technical staff reviewing the I&C portions of LAR, noted that the description of Section 3.3, Reduction of the P-8 Power Range Neutron Flux Nominal Trip Setpoint and Alllowable Value, does not make any statement about instrument uncertainty.

The staff requests licensee confirmation that the associated instrument uncertainty analysis/calculation remains bounding or applicable. The staff recognizes that the amount of uncertainty (delta 0.6%) did not change, but the operating region with it applied did change. Therefore, the staff would like to get some confirmation that the licensee reviewed or verified the associated instrument uncertainty and the reasoning that it remains bounding or valid (e.g., the shift in the operating region from 50% to 35% is such a small shift that the uncertainty calculation remains valid). If the calc/analysis was revised, the staff would request a summary of the changes.

Please let me know if you need any further information for responding to the above request.

Thanks,

~~~~~~~~~~~~

Rich Guzman Sr. PM, Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Office: O-10H17 l Phone: (301) 415-1030 Richard.Guzman@nrc.gov