ML24024A020

Correction to Safety Evaluation Associated Wit Amendment No. 288 - Revision to Applicability Term for RCS Heat-Up and Cooldown Pressure-Temperature Limitations Figures

ML24024A020
Person / Time
Site:	Millstone
Issue date:	01/24/2024
From:	Richard Guzman NRC/NRR/DORL/LPL1
To:	Sinha S Dominion Energy Nuclear Connecticut
References
EPID L-2023-LLA-0009
Download: ML24024A020 (1)

Text

From: Richard Guzman To: shayan.sinha@dominionenergy.com

Subject:

Millstone Power Station, Unit No. 3 - Correction to Safety Evaluation associated wit Amendment No. 288 -

Revision to Applicability Term for RCS Heatup and Cooldown Pressure-Temperature Limitations Figures (EPID L-2023-LLA-0009)

Date: Wednesday, January 24, 2024 7:51:58 AM

Shayan,

The NRC staff has reviewed your January 19, 2024, message and acknowledges that the highest adjusted reference temperature (ART) value for the extended beltline material of 49.7°F (two occurrences) stated on page 6 of the staffs subject safety evaluation (SE) dated January 12, 2024 (ML23341A017), was indeed in error. As per the licensees RAI response dated August 30, 2023 (ML23248A213), the stated temperature is 59.7°F. The statements in the SE should be revised to read as follows:

The highest ART value for the extended beltline materials is 59.7°F which occurs at the 1/4T location of nozzle shell plate B9804-1 based on the projected neutron fluence at 54 EFPY. The NRC staff noted that 59.7°F is lower than the limiting ART value of 118.7°F for the lower shell plate B9820-2 of the beltline region.

The NRC staff notes that the corrected error does not alter the staffs technical basis and safety conclusion as stated in the SE. Please consider this e-mail as documentation of the error as stated above. This communication will be added to ADAMS as an official agency record.

Thank you for your attention on this matter.

Rich Guzman Sr. PM, Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Office: O-9C7 l Phone: (301) 415-1030 Richard.Guzman@nrc.gov

From:shayan.sinha@dominionenergy.com <shayan.sinha@dominionenergy.com >

Sent: Friday, January 19, 2024 8:33 AM To: Richard Guzman < Richard.Guzman@nrc.gov>

Subject:

[External_Sender] RE: ADVANCED LISTSERV: Millstone Power Station, Unit No. 3 - Issuance of Amendment No. 288 Re: Revision to Applicability Term for Reactor Coolant System Heatup and Cooldown Pressure-Temperature Limitations Figures (EPID L-2023-LLA-0009)

Good Morning Rich, Dominion has reviewed the SE for MPS3 Amendment 288 (Pressure-Temperature Limit Applicability Revision) and wanted to note one potential minor error. The paragraph below is pasted below from Page 6 of the SE:

Tables 10 and 11 of Attachment 2 to the licensees supplemental letter dated August 30,

2023, presents the ART values for the extended beltline materials, including nozzle shell plate

B9804, inlet nozzles B9806, nozzle shell welds, and inlet nozzle welds. The highest ART value for the extended beltline materials is 49.7°F which occurs at the 1/4T location of nozzle shell plate B9804-1 based on the projected neutron fluence at 54 EFPY. The NRC staff noted that 49.7°F is lower than the limiting ART value of 118.7°F for the lower shell plate B9820-2 of the beltline region. The NRC staff verified that the limiting ART value of the beltline region bounds the limiting ART value of the extended beltline materials. As such, the ART values of the extended beltline materials do not affect the applicability of the 32 EFPY P-T limit curves. The NRC staff confirmed that the licensee has considered the ART of all beltline materials in assessing the applicability of the existing 32 EFPY P-T limit curves and appropriately addressed the guidance of RIS 2014-11.

The highlighted values above indicate that a temperature of 49.7 F is associated with 1/4 T location, and is the highest ART value. However, we believe this value should be 57.9 F in both places, based on the value in the first row, last column of Table 10 (Attachment 2, Page 6 of 8) of our RAI Response for the LAR (ML23248A213). However, Dominion believes that this error does not impact the technical argument or the conclusions of the SE.

If you have any questions, please let me know.

Thanks, Shayan