[Federal Register Volume 88, Number 43 (Monday, March 6, 2023)]
[Notices]
[Pages 13855-13859]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-04501]


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NUCLEAR REGULATORY COMMISSION

[NRC-2023-0036]


NRC Bulletin 2012-01: Design Vulnerability in Electric Power 
System

AGENCY: Nuclear Regulatory Commission.

ACTION: Bulletin; closure.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing this 
notice to inform all holders of operating licenses and combined 
licenses for nuclear power reactors of the closure of ``NRC Bulletin 
2012-01: Design Vulnerability in Electric Power System'' (Bulletin). 
NRC has completed evaluations and inspections of the responses and 
other actions taken by the licensees of the nuclear power plants in 
response to NRC Bulletin 2012-01. The staff has approved the actions to 
be taken by the licensee for Vogtle Units 3 and 4 following 
commencement of operations and will inspect these actions under the 
Reactor Oversight Process. The NRC staff concludes that any potential 
adverse impact on nuclear plant safety due to an open phase condition 
(OPC) in the plant offsite power system has been adequately addressed 
by the licensees.

DATES: NRC Bulletin 2012-01 is closed effective March 6, 2023.

ADDRESSES: Please refer to NRC-2023-0036 when contacting the NRC about 
the availability of information regarding this document. You may obtain 
publicly available information related to this document using any of 
the following methods:
     Federal Rulemaking Website: Go to https://www.regulations.gov and search for NRC-2023-0036. Address questions 
about Docket IDs in Regulations.gov to Stacy Schumann; telephone: 301-
415-0624; email: [email protected]. For technical questions, 
contact the individual listed in the For Further Information Contact 
section of this document.
     NRC's Agencywide Documents Access and Management System 
(ADAMS): You may obtain publicly available documents online in the 
ADAMS Public Documents collection at https://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``Begin Web-based ADAMS 
Search.'' For problems with ADAMS, please contact the NRC's Public 
Document Room (PDR) reference staff at 1-800-397-4209, 301-415-4737, or 
by email to [email protected]. For the convenience of the reader, 
instructions about obtaining materials referenced in

[[Page 13856]]

this document are provided in the ``Availability of Documents'' 
section.
     NRC's PDR: You may examine and purchase copies of public 
documents, by appointment, at the NRC's PDR, Room P1 B35, One White 
Flint North, 11555 Rockville Pike, Rockville, Maryland 20852. To make 
an appointment to visit the PDR, please send an email to 
[email protected] or call 1-800-397-4209 or 301-415-4737, between 8 
a.m. and 4 p.m. eastern time (ET), Monday through Friday, except 
Federal holidays.

FOR FURTHER INFORMATION CONTACT: Wendell Morton, Office of Nuclear 
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001, telephone: 301-415-1658, email: [email protected].

SUPPLEMENTARY INFORMATION: 

I. Introduction

    The NRC is providing this technical summary in this Federal 
Register notice (FRN) to explain the basis for closure of ``NRC 
Bulletin 2012-01: Design Vulnerability in Electric Power System.'' This 
FRN informs external stakeholders that the adverse impacts on nuclear 
plant safe operation due to an OPC in the plant offsite power system 
have been adequately addressed, and the Bulletin is closed.

II. Background

    An OPC event occurred in the offsite power circuit at Bryon Unit 2 
on January 30, 2012. The station auxiliary transformer (SAT) (offsite 
power source) high-voltage side event caused unbalanced voltage 
conditions on the low-voltage side of the SAT, which led to a reactor 
trip and tripping of certain safety related loads. The existing 
undervoltage degraded voltage protection scheme failed to detect the 
unbalanced voltage and did not automatically separate the degraded 
offsite power source from the onsite power source. Operator action was 
required to bring the plant to a safe shutdown condition. The event is 
further described in the ``Availability of Documents'' section.
    In addition to the event previously described, two additional 
events were discussed in NRC Information Notice 2012-03. In these 
events, the OPC occurred on the offsite circuits that usually remain 
energized without a load or with a light load during normal conditions. 
At the related plants, the safety and non-safety-related loads are 
normally fed from the main generator through unit auxiliary 
transformers, therefore the offsite circuits that feed the safety-
related loads during plant startup or after unit trip usually remain on 
no-load or are lightly loaded during normal plant conditions. The OPCs 
at these plants were not detected for many days. If a design basis 
event had occurred simultaneously, the unbalanced voltages at the 
safety-related buses would have increased due to shifting of loads from 
unit auxiliary transformers to offsite circuits due an OPC and could 
impact the safety of plants. The degree of unbalanced voltage 
conditions on the plant buses due to an OPC in the offsite power 
circuit is dependent on the offsite circuit design parameters, plant 
configuration, and plant loading conditions. The unbalanced voltage 
condition can potentially lead to either degraded operation of the 
safety-related loads if the voltage unbalance is small (about five 
percent or less) or tripping of the safety-related loads if the voltage 
unbalance is large, either of which is an unsafe condition. Therefore, 
the timely mitigation of an OPC is necessary to ensure the safety of 
the plant.
    In light of the Byron and other events, on July 27, 2012, the NRC 
issued Bulletin 2012-01: Design Vulnerability in Electric Power System. 
The Bulletin required that all holders of operating licenses and 
combined licenses for nuclear power reactors verify compliance with the 
regulatory requirements of General Design Criterion (GDC) 17, 
``Electric Power Systems,'' in Appendix A, ``General Design Criteria 
for Nuclear Power Plants,'' to Part 50 of title 10 of the Code of 
Federal Regulations (10 CFR) or the applicable principal design 
criteria in the licensees' updated final safety analysis report; and 
the design criteria for protection systems under 10 CFR 50.55a(h)(2) or 
10 CFR 50.55a(h)(3). The licensees were requested to describe plant 
design features that would allow the existing protective schemes to 
detect and respond to an OPC.
    Licensees provided responses to the Bulletin and the NRC staff 
issued a summary report of the responses on February 26, 2013. In the 
summary report, the staff determined that for the operating plants, one 
or both trains of safety related electrical buses could be affected by 
an OPC. The NRC staff became aware of the OPC during an event at Byron 
Unit 2 that rendered both the offsite power system and the onsite power 
system unable to perform their intended safety functions. The NRC 
determined further regulatory action was required to ensure detection 
and automatic system response to an OPC at nuclear power plants. 
Further, the NRC determined that licensees should ensure that offsite 
and onsite electric power systems would remain available to permit the 
functioning of structures, systems, and components important to safety 
in the event of anticipated operational occurrences and accidents.

III. Discussion

    Two public meetings were held with industry on February 13, 2013, 
and June 13, 2013, in which various industry representatives presented 
possible solutions for the detection and protection from the new 
challenge faced due to OPCs. The minutes from these meetings as well as 
presentations by industry representatives are available in the 
``Availability of Documents'' section.
    In its letter dated October 9, 2013, Nuclear Energy Institute (NEI) 
provided a voluntary industry initiative plan, which included a formal 
commitment by the licensees to address plant vulnerabilities due to 
potential OPCs. The initiative goal and definition included: an OPC 
will not prevent functioning of important-to-safety structures, 
systems, and components. An OPC is defined as an open phase, with or 
without a ground, which is located on the high voltage side of a 
transformer connecting a GDC 17 off-site power circuit to the 
transmission system. The initiative was slated for completion by 
December 31, 2017.
    Bulletin 2012-01 stated that GDC 17 in 10 CFR part 50, Appendix A, 
and 10 CFR 50.55a(h)(2) for operating plants or 10 CFR 50.55a(h)(3) for 
any plants after May 13, 1999, are applicable.
    In its letter dated March 21, 2014, NEI provided its perspective 
that the protection system requirements described in 10 CFR 
50.55a(h)(2), ``Protection systems,'' do not apply to the Open Phase 
Isolation Systems (OPISs).
    In the letter dated August 14, 2014, NEI provided the industry 
position with respect to various regulatory issues related to OPC.
    The NRC provided a November 25, 2014, response to NEI to address 
the issues raised in the March 2014 and August 2014 letters, and 
explained that to address OPCs, four functional requirements should be 
met. The letter also stated that until each licensee has addressed OPCs 
and informed the NRC that it is in full compliance with GDC 17, or the 
principal design criteria specified in the updated final safety 
analysis report for the specific plant regarding OPC, the staff would 
be recommending an interim enforcement policy (IEP) to the Commission.
    NEI provided Revision 1 of the voluntary industry initiative dated 
March 16, 2015, with a schedule change for OPC modifications completion 
from

[[Page 13857]]

December 31, 2017, to December 31, 2018.
    In SECY-16-0068, dated May 31, 2016, the NRC staff proposed a 
revision to the Enforcement Policy to permit the staff to exercise 
enforcement discretion for certain noncompliance's with technical 
specifications or GDC 17, and certain nonconformances with the 
analogous principal design criteria specified in the updated final 
safety analysis report, as well as noncompliance's with 10 CFR 
50.55a(h)(2) or 10 CFR 50.55a(h)(3), and 10 CFR 50.36. The potential 
violations could be those associated with inoperable electrical power 
systems (offsite and onsite) caused by an OPC design vulnerability in 
the offsite electric power system that would require a reactor shutdown 
or prevent a reactor startup if a licensee could not come into 
conformance within the technical specification required completion 
times.
    In SRM-SECY-16-0068 dated March 9, 2017, the Commission disapproved 
the staff's request to establish an IEP. Instead, the Commission 
directed the staff to (1) verify that licensees have appropriately 
implemented the voluntary industry initiative; (2) update the Reactor 
Oversight Process to provide periodic oversight of industry's 
implementation of the OPC initiative; and (3) close the Bulletin once 
satisfactory implementation of the technical resolution has been 
verified for each licensee.
    On October 31, 2017, the NRC staff issued Temporary Instruction 
2515/194, to verify that licensees appropriately implemented the NEI 
voluntary industry initiative. The NRC inspectors verified 
implementation at plants where OPC modifications were substantially 
complete.
    NEI provided Revision 2 of the voluntary industry initiative, dated 
September 20, 2018, with the completion schedule changed from December 
31, 2018, to December 31, 2019. NEI stated that many plants had 
completed installation of OPIS with other plants scheduled to complete 
during 2018. However, the monitoring data to date had indicated that 
installed OPISs would have experienced undesirable spurious actuations 
if the automatic trip functions had been activated. NEI proposed 
extended monitoring periods so that licensees could refine OPIS 
setpoints to minimize spurious actuations.
    Due to continuing spurious actuations of OPIS designs observed at 
some plants, NEI provided Revision 3 dated June 6, 2019, of the 
initiative. This revision included an option to perform a risk 
evaluation under certain boundary conditions to support an alarm and 
manual response to an OPC, instead of an automatic trip response. For 
plants adopting the risk-informed option, the OPIS design would change 
from ``alarm and automatically trip (isolate)'' to ``alarm (detect) and 
manual actions'' to isolate the OPC. Written plant alarm response 
procedures would allow operators to diagnose and take manual actions to 
mitigate an OPC. NEI also separately provided NEI 19-02, ``Guidance for 
Assessing Open Phase Condition Implementation Using Risk Insights,'' 
referenced in Revision 3 of the initiative.
    To evaluate whether safety significance justified requiring 
automatic OPIS actuation, the NRC staff performed a backfit screening 
and documented the results in a memo dated May 21, 2020. The analysis 
determined that automatic OPIS actuation would not result in a 
substantial increase in the overall protection of the public health and 
safety. Therefore, the risk-informed option in Revision 3 to the 
voluntary industry initiative was acceptable.
    On August 18, 2020, the NRC staff issued Revision 2 of the 
Temporary Instruction 2515/194, to verify that licensees have 
appropriately implemented the NEI voluntary industry initiative, 
including licensees that adopted the risk-informed option. For 
licensees where OPIS implementation was still in the monitoring mode 
and spurious initiations continued to occur, many changed to the risk-
informed option of the voluntary industry initiative. Approximately 65 
percent of operating power reactors have adopted the risk-informed 
option. This change, and the COVID-19 pandemic, resulted in delays in 
licensees' implementation of the voluntary industry initiative and the 
subsequent inspections at many plants.
    As required by SRM-SECY-16-0068, the Reactor Oversight Process 
Inspection Procedures and the Inspection Manual Chapter were revised to 
provide periodic oversight of industry's implementation of the OPC 
voluntary industry initiative.

IV. Conclusion

    The staff issued closure letters to each licensee other than 
Southern Nuclear Company for Vogtle Units 3 and 4. ADAMS accession 
numbers to these letters are in the ``Availability of Documents'' 
section. The closure letters provide further details concerning how 
licensees addressed OPC at their facilities.
    The staff has approved the actions to be taken by the licensee for 
Vogtle Units 3 and 4 following commencement of operations, by letter 
dated July 5, 2019, agreeing to the due dates and will inspect these 
actions under the Reactor Oversight Process. By letter dated August 29, 
2018, Southern Nuclear Company to NRC (Vogtle Units 3 and 4), provided 
regulatory commitments and due dates regarding the OPC.
    The licensees of the following plants received Bulletin 2012-01, 
but subsequently permanently ceased operation prior to addressing the 
Bulletin: Crystal River 3; Duane Arnold; Fort Calhoun; Indian Point 2; 
Kewaunee; Oyster Creek; Palisades; Pilgrim 1; San Onofre 2; San Onofre 
3; Three Mile Island 1; Vermont Yankee.
    Based on the actions taken by the NRC and licensees in response to 
the Bulletin, the NRC staff finds that all operating plants will 
continue to operate safely or safely shut down in response to an OPC 
event. Therefore, Bulletin 2012-01 is closed.

V. Availability of Documents

    The documents identified in the following table are available to 
interested persons through one or more of the following methods, as 
indicated.

------------------------------------------------------------------------
              Document description                  ADAMS accession No.
------------------------------------------------------------------------
Information Notice 2012-03: Design Vulnerability  ML120480170.
 in Electric Power System, dated March 1, 2012.
Presentation by Exelon Nuclear--Byron Station     ML120810365.
 Single Phase Failure, dated March 22, 2012.
Licensee Event Report 2012-001-01 ``Unit 2 Loss   ML12272A358.
 of Normal Offsite Power and Reactor Trip and
 Unit 1 Loss of Normal Offsite Power Due to
 Failure of System Auxiliary Transformer
 Inverted Insulators,'' dated September 28, 2012.
Byron Unit 2--NRC Special Inspection Team (SIT)   ML12087A213.
 Report, dated March 27, 2012.
Bulletin 2012-01: Design Vulnerability in         ML12074A115.
 Electric Power System, dated July 27, 2012.
Summary report of licensee responses, dated       ML13052A711.
 February 26, 2013.
Public meeting summary..........................  ML13066A774 (package).
Public meeting summary..........................  ML13196A002 (package).

[[Page 13858]]

 
Nuclear Energy Institute (NEI) voluntary          ML13333A147.
 industry initiative plan, dated October 9, 2013.
NEI perspective letter on Open Phase Isolation    ML14087A252 (package).
 Systems (OPISs), dated March 21, 2014.
NEI letter that provided the industry position    ML14226A804 (package).
 with respect to various regulatory issues
 related to OPC, dated August 14, 2014.
NRC's response to NEI to address the issues       ML14120A203.
 raised in the March 2014 and August 2014
 letters, and explained that to address OPCs,
 four functional requirements should be met,
 dated November 25, 2014.
NEI Revision 1 of the voluntary industry          ML15075A454 (package).
 initiative plan, dated March 16, 2015.
SECY-16-0068, dated May 31, 2016................  ML15219A327, Enclosure
                                                   ML15219A330.
SRM-SECY-16-0068, dated March 9, 2017...........  ML17068A297.
NRC staff issued Temporary Instruction 2515/194,  ML17137A416.
 dated October 31, 2017.
NEI Revision 2 of the voluntary industry          ML18268A114.
 initiative, dated September 20, 2018.
NEI Revision 3 of the voluntary industry          ML19163A176.
 initiative, dated June 6, 2019.
NEI 19-02, ``Guidance for Assessing Open Phase    ML19172A086.
 Condition Implementation Using Risk Insights,''
 dated June 20, 2019.
NRC backfit screening memo, dated May 21, 2020..  ML19198A304.
NRC Revision 2 of the Temporary Instruction 2515/ ML20230A328.
 194, dated August 18, 2020.
NRC Response to Supplemental Information for      ML19182A206.
 Bulletin 2012-01, Vogtle 3 and 4 (052-25 and 52-
 026), dated July 5, 2019.
Vogtle, Units 3 and 4, Supplement to Response to  ML18242A012.
 NRC Bulletin 2012-01, Design Vulnerability in
 Electric Power System, dated August 29, 2018.
Arkansas Nuclear 1 Closure Letter, dated March    ML21049A307.
 5, 2021.
Arkansas Nuclear 2 Closure Letter, dated March    ML21049A307.
 5, 2021.
Beaver Valley 1 Closure Letter, dated July 15,    ML22189A184.
 2022.
Beaver Valley 2 Closure Letter, dated July 15,    ML22189A184.
 2022.
Braidwood 1 Closure Letter, dated April 27, 2021  ML21102A182.
Braidwood 2 Closure Letter, dated April 27, 2021  ML21102A182.
Browns Ferry 1 Closure Letter, dated May 1, 2020  ML20104A192.
Browns Ferry 2 Closure Letter, dated May 1, 2020  ML20104A192.
Browns Ferry 3 Closure Letter, dated May 1, 2020  ML20104A192.
Brunswick 1 Closure Letter, dated October 12,     ML21278A002.
 2021.
Brunswick 2 Closure Letter, dated October 12,     ML21278A002.
 2021.
Byron 1 Closure Letter, dated April 27, 2021....  ML21102A182.
Byron 2 Closure Letter, dated April 27, 2021....  ML21102A182.
Callaway Closure Letter, dated July 27, 2021....  ML21201A105.
Calvert Cliffs 1 Closure Letter, dated September  ML21225A432.
 7, 2021.
Calvert Cliffs 2 Closure Letter, dated September  ML21225A432.
 7, 2021.
Catawba 1 Closure Letter, dated October 19, 2021  ML21272A183.
Catawba 2 Closure Letter, dated October 19, 2021  ML21272A183.
Clinton Closure Letter, dated July 8, 2022......  ML22186A150.
Columbia Closure Letter, dated June 29, 2021....  ML21165A344.
Comanche Peak 1 Closure Letter, dated July 26,    ML23025A353.
 2023.
Comanche Peak 2 Closure Letter, dated July 26,    ML23025A353.
 2023.
Cooper Closure Letter, dated November 22, 2021..  ML21323A074.
D.C. Cook 1 Closure Letter, dated May 26, 2021..  ML22146A113.
D.C. Cook 2 Closure Letter, dated May 26, 2021..  ML22146A113.
Davis-Besse Closure Letter, dated July 21, 2022.  ML22195A223.
Diablo Canyon 1 Closure Letter, dated April 29,   ML22108A286.
 2022.
Diablo Canyon 2 Closure Letter, dated April 29,   ML22108A286.
 2022.
Dresden 2 Closure Letter, dated April 27, 2021..  ML21102A182.
Dresden 3 Closure Letter, dated April 27, 2021..  ML21102A182.
Farley 1 Closure Letter, dated August 23, 2021..  ML21216A316.
Farley 2 Closure Letter, dated August 23, 2021..  ML21216A316.
Fermi 2 Closure Letter, dated July 21, 2022.....  ML22188A089.
FitzPatrick Closure Letter, November 16, 2021...  ML21300A006.
Ginna Closure Letter, dated September 20, 2021..  ML21245A098.
Grand Gulf Closure Letter, dated March 5, 2021..  ML21049A307.
Harris 1 Closure Letter, dated September 29,      ML21252A389.
 2021.
Hatch 1 Closure Letter, dated September 20, 2021  ML21253A113.
Hatch 2 Closure Letter, dated September 20, 2021  ML21253A113.
Hope Creek 1 Closure Letter, dated March 11,      ML22060A057.
 2022.
Indian Point 3 Closure Letter, dated March 5,     ML21049A307.
 2021.
La Salle 1 Closure Letter, dated April 27, 2021.  ML21102A182.
La Salle 2 Closure Letter, dated April 27, 2021.  ML21102A182.
Limerick 1 Closure Letter, dated September 13,    ML21245A084.
 2021.
Limerick 2 Closure Letter, dated September 13,    ML21245A084.
 2021.
McGuire 1 Closure Letter, dated October 27, 2021  ML21293A026.
McGuire 2 Closure Letter, dated October 27, 2021  ML21293A026.
Millstone 2 Closure Letter, dated November 15,    ML21295A412.
 2021.
Millstone 3 Closure Letter, dated November 15,    ML21295A412.
 2021.
Monticello Closure Letter, dated July 29, 2022..  ML22189A019.
Nine Mile Point 1 Closure Letter, dated           ML21239A052.
 September 7, 2021.
Nine Mile Point 2 Closure Letter, dated           ML21239A052.
 September 7, 2021.
North Anna 1 Closure Letter, dated May 5, 2020..  ML20065L173.

[[Page 13859]]

 
North Anna 2 Closure Letter, dated May 5, 2020..  ML20065L173.
Oconee 1 Closure Letter, dated February 17, 2022  ML22045A024.
Oconee 2 Closure Letter, dated February 17, 2022  ML22045A024.
Oconee 3 Closure Letter, dated February 17, 2022  ML22045A024.
Palo Verde 1 Closure Letter, April 20, 2022.....  ML22102A262.
Palo Verde 2 Closure Letter, April 20, 2022.....  ML22102A262.
Palo Verde 3 Closure Letter, April 20, 2022.....  ML22102A262.
Peach Bottom 2 Closure Letter, dated September    ML21196A010.
 7, 2021.
Peach Bottom 3 Closure Letter dated September 7,  ML21196A010.
 2021.
Perry 1 Closure Letter, dated July 13, 2022.....  ML22189A177.
Point Beach 1 Closure Letter, dated July 13,      ML21187A153.
 2021.
Point Beach 2 Closure Letter, dated July 13,      ML21187A153.
 2021.
Prairie Island 1 Closure Letter, dated May 26,    ML22145A020.
 2022.
Prairie Island 2 Closure Letter, dated May 26,    ML22145A020.
 2022.
Quad Cities 1 Closure Letter, dated April 27,     ML21102A182.
 2021.
Quad Cities 2 Closure Letter, dated April 27,     ML21102A182.
 2021.
River Bend 1 Closure Letter, dated March 5, 2021  ML21049A307.
Robinson 2 Closure Letter, dated March 29, 2022.  ML22083A003.
Saint Lucie 1 Closure Letter, dated October 28,   ML21281A012.
 2021.
Saint Lucie 2 Closure Letter, dated October 28,   ML21281A012.
 2021.
Salem 1 Closure Letter, dated November 19, 2021.  ML21320A204.
Salem 2 Closure Letter, dated November 19, 2021.  ML21320A204.
Seabrook 1 Closure Letter, dated March 24, 2020.  ML20071C899.
Sequoyah 1 Closure Letter, dated May 1, 2020....  ML20104A192.
Sequoyah 2 Closure Letter, dated May 1, 2020....  ML20104A192.
South Texas 1 Closure Letter, dated August 5,     ML20206L260.
 2020.
South Texas 2 Closure Letter, dated August 5,     ML20206L260.
 2020.
Surry 1 Closure Letter, dated May 5, 2020.......  ML20065L173.
Surry 2 Closure Letter, dated May 5, 2020.......  ML20065L173.
Susquehanna 1 Closure Letter, dated December 6,   ML21335A422.
 2021.
Susquehanna 2 Closure Letter, dated December 6,   ML21335A422.
 2021.
Turkey Point 3 Closure Letter, dated July 19,     ML22187A277.
 2022.
Turkey Point 4 Closure Letter, dated July 19,     ML22187A277.
 2022.
VC Summer Closure Letter, dated September 14,     ML21242A330.
 2021.
Vogtle 1 Closure Letter, dated October 22, 2021.  ML21279A167.
Vogtle 2 Closure Letter, dated October 22, 2021.  ML21279A167.
Waterford 3 Closure Letter, dated June 22, 2020.  ML20171A366.
Watts Bar 1 Closure Letter, dated May 1, 2020...  ML20104A192.
Watts Bar 2 Closure Letter, dated May 1, 2020...  ML20104A192.
Wolf Creek 1 Closure Letter, dated February 10,   ML22040A158.
 2022.
------------------------------------------------------------------------


    Dated: March 1, 2023.

    For the Nuclear Regulatory Commission.
Lisa M. Regner,
Chief, Generic Communication and Operating Experience Branch, Division 
of Reactor Oversight, Office of Nuclear Reactor Regulation.
[FR Doc. 2023-04501 Filed 3-3-23; 8:45 am]
BILLING CODE 7590-01-P