ML22278A093

E-mail to File - Summary of September 7, 2022, Meeting with Dominion to Discuss Proposed Supplement to the Spent Fuel Pool Criticality Safety Analysis (EPID L-2022-LRM-0059

ML22278A093
Person / Time
Site:	Millstone
Issue date:	10/05/2022
From:	Richard Guzman NRC/NRR/DORL/LPL1
To:	Gonzales H NRC/NRR/DORL/LPL1
Guzman R
References
EPID L-2022-LRM-0059
Download: ML22278A093 (3)

Text

From: Richard Guzman To: Hipo Gonzalez

Subject:

Memo E-mail to File - Summary of September 7, 2022, Meeting with Dominion to Discuss Proposed Supplement to Spent Fuel Pool Criticality Safety Analysis (EPID L:2022-LRM-0059)

Date: Wednesday, October 05, 2022 11:28:06 AM

Hipo, For your information, shown below is a summary of the September 7, 2022, observation meeting with Dominion Energy Nuclear Connecticut, Inc. to discuss the licensees planned supplement to the Spent Fuel Pool Criticality Safety Analysis at Millstone Power Station, Unit No. 3. This communication will be added to ADAMS as an official agency record and Listservd. Please contact me if you have any questions regarding this meeting.

Rich Guzman Sr. PM, Division Operator Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Office: O-9C7 l Phone: (301) 415-1030 Richard.Guzman@nrc.gov CATEGORY 1 PUBLIC MEETING WITH DOMINION ENERGY NUCLEAR CONNECTICUT, INC. (DENC),

TO DISCUSS PROPOSED SUPPLEMENT TO SPENT FUEL POOL CRITICALITY SAFETY ANALYSIS MILLSTONE POWER STATION, UNIT NO. 3 PRE-APPLICATION MEETING MEETING

SUMMARY

SEPTEMBER 7, 2022 DOCKET NO. 50-423 The U.S. Nuclear Regulatory Commission (NRC or the staff) and representatives of Dominion Energy Nuclear Connecticut, Inc. (DENC, the licensee) held a public meeting via teleconference call on September 7, 2022, to discuss the licensees planned alternative request for Millstone Power Station, Unit No. 3 (MPS3) related to the proposed supplement to the spent fuel pool (SFP) criticality safety analysis (CSA). The licensees meeting slides are available in ADAMS at Accession No. ML22243A032. The licensees presentation is summarized as follows:

Background

The licensee began the presentation with background on the (three) different types of SFP at MPS3: Region 1 (Boral poisoned, flux trap design), Region 2 (Boral poisoned, non-flux trap design, and Region 3 (Uncredited Boraflex, flux trap design). The licensee stated the current CSA which was based on the methodology per Nuclear Energy Institute (NEI) 12-16, Revision 3, was submitted in 2018 and approved by the NRC in 2019. The current CSA

takes credit for burnup and demonstrates that the burnable poison (BP) wet annular burnable absorber (WABA) bounds the integral fuel burnable absorber (IFBA) during depletion. However, the current CSA does not address the use of gadolinia as a BP.

Therefore, since the licensee plans to implement a new fuel assembly design which uses the BP, gadolinia, a license amendment request is needed for approval to approve the revised CSA, updated to address depletion credit, justifying that gadolinia is bounded.

Proposed Resolution The licensee intends to submit a supplement to the MPS3 CSA that (1) justifies through previous evaluation that the use of gadolinia BP is bounded by the current CSAs burnup credit analysis and (2) demonstrates the previous evaluations applicability to MPS3. The proposed change will not involve any changes to the MPS3 Technical Specifications, and no credit is being taken for gadolinia in fresh fuel. Additionally, the scope of the submittal will not involve any calculations that would need to be added or revised to the current CSA.

Specifically, the only change is to extend the burnup credits bounds of applicability.

Proposed Justification The licensee will provide a justification discussion relative to the following NRC endorsed guidance in Regulatory Guide (RG) 1.240:

• RG 1.240 endorses NEI 12-16, Revision 4

• NEI 12-16 states modeling no gadolinia is conservative during depletion

• NEI 12-16 references NUREG/CR-6760 and EPRI 3002008197

• The reports investigated the effects of gadolinia on burnup credit and concluded its use to be conservative

• The licensee will demonstrate that these findings are applicable to MPS3 Additionally, the licensee intends to include precedent submittals (namely, Prairie Island (2013) and Millstone Unit 2 (2016)) in their justification write-up to support that the effects of gadolinia on burnup credit and its use is conservative and applicable to MPS3.

Schedule The licensee stated their planned submittal is on track and targeted for 4Q2022. DENC intends to request an approval date in 4Q2023 (i.e., one year from the submission date) to support implementation by the MPS3 spring 2025 (3R23) outage.

Conclusion DENC completed its presentation with no open/unanswered questions from the staff and summarized its conclusion by stating that the depletion analysis in the current MPS3 SFP CSA bounds the effects associated with the use of gadolinia BP which is supported by (1) industry guidance that demonstrates gadolinia can conservatively be unmodeled in the depletion analysis and is applicable to MPS3, and (2) other licensee submittals that have been approved by the NRC are applicable to MPS3 and have also demonstrated gadolinia can conservatively be unmodeled in the depletion analysis.

No decisions were made regarding the acceptability of the licensees proposed submittal.

There were no members of the public in attendance. To date, no public meeting feedback forms have been submitted through the NRC public meeting feedback system.

LIST OF ATTENDEES OCTOBER 7, 2022, CATEGORY 1 PUBLIC MEETING WITH DOMINION ENERGY NUCLEAR CONNECTICUT, INC. (DENC),

TO DISCUSS PROPOSED SUPPLEMENT TO THE SPENT FUEL POOL CRITICALITY SAFETY ANALYSIS MILLSTONE POWER STATION, UNIT NO. 3 DOCKET NO. 50-423 ATTENDEE ORGANIZATION Richard Guzman U.S. Nuclear Regulatory Commission (NRC)

Kent Wood NRC Brandon Wise NRC Shayan Sinha DENC Craig Sly DENC Kasey Kennett DENC Timothy Olsowy DENC Daniel Beachy DENC Chris Wells DENC Jared Cantrell DENC James Stanley DENC Dean Rowe DENC Brian Vitiello DENC