[Federal Register Volume 90, Number 87 (Wednesday, May 7, 2025)]
[Notices]
[Pages 19322-19325]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-07960]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-613; NRC-2024-0078]


US SFR Owner, LLC.; Kemmerer Power Station, Unit 1; Environmental 
Assessment and Finding of No Significant Impact

AGENCY: Nuclear Regulatory Commission.

ACTION: Notice; issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) staff is making a 
finding of no significant impact (FONSI) for a proposed issuance of an 
exemption in response to a February 28, 2025 request, as supplemented 
by letters dated April 7, and April 29, 2025, for the proposed Kemmerer 
Power Station Unit 1 (Kemmerer 1) facility. Specifically, TerraPower, 
LLC (TerraPower), on behalf of its wholly-owned subsidiary US SFR 
Owner, LLC (USO), requested an exemption that would modify a portion of 
the definition of construction applicable to the prohibition on 
construction of production and utilization facilities without an NRC 
license for the proposed Kemmerer 1. If granted, this exemption would 
allow the driving of piles, subsurface preparation, placement of 
backfill, concrete, or permanent retaining walls within an excavation, 
installation of foundations, or in-place assembly, erection, 
fabrication or testing, which are for structures, systems, and 
components (SSCs) classified as non-safety-related with no special 
treatment (NST) the failure of which could cause a reactor scram or 
actuation of a safety-related system that are located on the proposed 
Kemmerer 1 energy island prior to receipt of a construction permit (CP) 
and without a limited work authorization. The NRC staff is issuing a 
final Environmental Assessment (EA) and FONSI associated with the 
proposed exemption request.

DATES: The EA and FONSI referenced in this document are available on 
May 7, 2025.

ADDRESSES: Please refer to Docket ID NRC-2024-0078 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 Docket ID NRC-2024-0078. Address 
questions about Docket IDs in Regulations.gov to Bridget Curran; 
telephone: 301-415-1003; 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, at 301-415-4737, 
or by email to [email protected]. For the convenience of the reader, 
instructions about obtaining materials referenced in this document are 
provided in the ``Availability of Documents'' section.
     NRC's PDR: The PDR, where you may examine and order copies 
of publicly available documents, is open by appointment. 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: Mallecia Sutton, Office of Nuclear 
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001; telephone: 301-415-0673; email: [email protected].

SUPPLEMENTARY INFORMATION:

I. Introduction

    By letter dated March 28, 2024, TerraPower, LLC (TerraPower), on 
behalf of its wholly-owned subsidiary

[[Page 19323]]

US SFR Owner, LLC (USO), submitted a construction permit (CP) 
application, including an environmental report to the NRC staff for a 
reactor facility pursuant to part 50 of title 10 of the Code of Federal 
Regulations (10 CFR), ``Domestic Licensing of Production and 
Utilization Facilities,'' and section 103 of the Atomic Energy Act of 
1954, as amended. The proposed facility, referred to as Kemmerer Power 
Station Unit 1 (Kemmerer 1), if approved, would be built in Lincoln 
County, Wyoming and utilize TerraPower and General Electric-Hitachi 
Natrium sodium fast reactor technology. Supplements to the application 
were submitted on May 2, 2024, and May 9, 2024. On May 21, 2024, the 
NRC staff accepted the CP application for docketing (89 FR 47997). This 
CP application is undergoing a separate review by the NRC staff. As 
part of that review, the NRC is preparing a detailed review of the 
environmental impact associated with the CP application, which proposes 
to construct a non-light water Natrium reactor for Kemmerer 1, in an 
environmental impact statement.
    By letter dated September 9, 2024, TerraPower submitted, on behalf 
of USO, an exemption request for the proposed Kemmerer 1. The requested 
exemptions were from the definitions of construction in 10 CFR 
50.10(a), ``Definitions,'' and 10 CFR 51.4, ``Definitions,'' and would 
have excluded all non-safety-related with no special treatment (NST) 
structures, systems, and components (SSCs) located on the energy island 
(EI) from the scope of construction as defined in these regulations. By 
letter dated February 28, 2025, TerraPower submitted, on behalf of USO, 
a new request that superseded the September 9, 2024 request and 
requested an exemption with a more limited scope. TerraPower, on behalf 
of USO, supplemented this request with letters dated April 7, and April 
29, 2025. In particular, the supplement dated April 29, 2025, withdrew 
the requested exemption from 10 CFR 51.4.
    As modified by the superseding exemption request and subsequent 
supplements, the NRC is considering issuance of an exemption that would 
modify the definition of construction in 10 CFR 50.10(a)(1)(iv) from 
``SSCs whose failure could cause a reactor scram or actuation of a 
safety-related system'' to ``SSCs whose failure could cause a reactor 
scram or actuation of a safety-related system, excluding Natrium EI 
SSCs classified as non-safety-related with no special treatment 
(NST).'' This specific exemption would allow USO to proceed with the 
driving of piles, subsurface preparation, placement of backfill, 
concrete, or permanent retaining walls within an excavation, 
installation of foundations, or the in-place assembly, erection, 
fabrication, or testing of SSCs classified as NST the failure of which 
could cause the reactor to scram or actuation of a safety-related 
system that are located on the proposed energy island (EI) without a 
limited work authorization while the NRC staff continues its review of 
the Kemmerer 1 CP application. If the NRC determines that approval of 
the exemption request is appropriate, the exemption would be issued to 
USO for the proposed Kemmerer 1.
    In accordance with 10 CFR 51.21, the NRC has prepared an EA that 
analyzes the environmental effects of the proposed action. Based on the 
results of the EA and in accordance with 10 CFR 51.31(a), the NRC has 
prepared a FONSI for the proposed exemption. Consistent with 10 CFR 
51.33, ``Draft finding of no significant impact; distribution,'' the 
NRC staff did not prepare a draft finding of no significant impact in 
this instance.

II. Environmental Assessment

Description of the Proposed Action

    The proposed action would modify the definition of construction in 
10 CFR 50.10(a)(1)(iv) from ``SSCs whose failure could cause a reactor 
scram or actuation of a safety-related system'' to ``SSCs whose failure 
could cause a reactor scram or actuation of a safety-related system, 
excluding Natrium EI SSCs classified as non-safety-related with no 
special treatment (NST).'' This specific exemption would allow USO to 
proceed with the driving of piles, subsurface preparation, placement of 
backfill, concrete, or permanent retaining walls within an excavation, 
installation of foundations, or the in-place assembly, erection, 
fabrication, or testing of SSCs classified as NST the failure of which 
could cause the reactor to scram or actuation of a safety-related 
system that are located on the proposed EI without a limited work 
authorization while the NRC staff continues its review of the Kemmerer 
1 CP application.
    Separate from this EA, the NRC staff is evaluating the proposed 
action against the relevant exemption criteria in 10 CFR 50.12, 
``Specific exemptions.'' The results of this review will be documented 
in a separate Federal Register notice. The NRC staff's review will 
determine whether the criteria in 10 CFR 50.12 are met. Further, the 
NRC staff is separately reviewing the submitted CP application and the 
environmental effects associated with approval, if appropriate, of the 
CP application. Issuing this exemption, if appropriate, would not 
constitute a commitment by the NRC to issue a CP for Kemmerer 1. If 
approved, USO would install the SSCs assuming the risk that its CP 
application may later be denied.

Need for the Proposed Action

    Issuance of the exemption would allow USO to begin the driving of 
piles, subsurface preparation, placement of backfill, concrete, or 
permanent retaining walls within an excavation, installation of 
foundations, or the in-place assembly, erection, fabrication, or 
testing of SSCs classified as NST the failure of which could cause the 
reactor to scram or actuation of a safety-related system that are 
located on the proposed EI without a limited work authorization while 
the NRC staff continues its review of the Kemmerer 1 CP application. As 
that work falls under the definition of construction in 10 CFR 
50.10(a), without this exemption, 10 CFR 50.10(c) would prohibit USO 
from performing that work under until the NRC staff issued it a CP or a 
limited work authorization, should that be appropriate.
    TerraPower, on behalf of USO, has indicated that if this work is 
delayed until issuance of the CP, it would result in substantial 
schedule delays for the proposed Kemmerer 1. TerraPower, on behalf of 
USO, also stated that, although the exact costs of delayed operation of 
Kemmerer 1 would depend on a number of uncertain factors, they are 
expected to be substantial.

Environmental Impacts of the Proposed Action

    In February 2025, the Department of Energy (DOE) Office of Clean 
Energy Demonstrations issued DOE/EA-2264, ``Final Environmental 
Assessment Kemmerer Power Station Unit 1 Preliminary Activities 
Kemmerer, Lincoln County, Wyoming,'' \1\ for the proposed action of 
authorizing the expenditure of Federal funding to conduct preliminary 
activities for the proposed Kemmerer 1. According to the DOE EA, the 
proposed action addresses preliminary activities that would occur prior 
to the NRC issuance of a CP for the Kemmerer 1 site. These preliminary 
activities are described in section 2.1, ``Proposed Action,'' of the 
DOE EA and include, among other things, the following:
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    \1\ https://www.energy.gov/sites/default/files/2025-02/final-ea-fonsi-appendices-2264-terrapower-kemmerer-unit-1-2024-10_1.pdf.
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     Earthwork activities, including site clearing and grubbing 
to remove the top layer of topsoil and organic material and

[[Page 19324]]

store it in a stockpile area for possible use as backfill.
     Dewatering activities, including establishing temporary 
dewatering systems to maintain dry working conditions for preliminary 
activities.
     Excavation and backfill activities, including the 
importation and placement of common and structural backfill, general 
excavation of the site, general backfill, development of spoil and 
laydown areas, placement of common fill, and construction of stormwater 
management ponds.
     Supporting infrastructure activities, including 
construction of buildings, temporary utilities, plant roads and 
parking, walkways, and storm drainage. Preliminary activities include 
the erection of buildings on the EI. Section 2.1.4.4, ``Buildings on 
the Energy Island,'' of the DOE EA states ``[t]hese activities would 
consist of excavation and backfill of the foundations, installation of 
mud mats, formwork, rebar and embeds, and placement of concrete. 
Embedded pipes and electrical conduit and grounding would be installed 
during foundation construction. Steel and superstructure would be 
installed after completion of the foundations.''
    The DOE EA determined that the environmental impacts of these 
activities on ecological resources; cultural resources; hydrology; 
socioeconomics; geological resources; and infrastructure, traffic, and 
transportation are minor. Based on this conclusion, DOE issued a 
finding of no significant impact.\2\ Although the DOE EA stated that it 
was considering activities that would occur before the NRC's issuance 
of the construction permit, it captured certain activities which 
require NRC authorization. Issuance of this exemption would allow the 
construction of buildings on the EI, which as described in section 
2.1.4.4 of the DOE EA, was included in the activities DOE considered. 
This includes the subsurface preparation, placement of backfill, and 
concrete, within an excavation, installation of foundations, and the 
in-place assembly or erection or fabrication of buildings classified as 
NST the failure of which could result in a reactor scram or actuation 
of a safety-related system located on the proposed Kemmerer 1 EI. The 
NRC staff reviewed the analysis in the DOE EA and determined that, 
because it already considered work that this exemption would approve, 
despite the different proposed actions, the DOE EA bounds those aspects 
of the work. Therefore, the NRC incorporates the DOE EA by reference 
into this EA.
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    \2\ https://www.energy.gov/sites/default/files/2025-02/final-ea-fonsi-2264-terrapower-kemmerer-unit-1-2024-10_0.pdf.
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    The NRC staff then considered the work that was not covered by the 
DOE EA. This work consists of the in-place assembly, erection, 
fabrication or testing of SSCs, apart from the buildings, classified as 
NST that are located within buildings on the proposed EI the failure of 
which could cause the reactor to scram or actuation of a safety-related 
system. As an initial matter, neither TerraPower nor USO are licensed 
to possess or use radiological materials. Since the proposed action 
does not involve operating the facility and there are no radiological 
materials on site, it would result in no significant changes in the 
types or amounts of radiological effluents that may be released 
offsite.
    Further, the work authorized by this exemption would occur in the 
same area of the site as the work considered by the DOE EA. Thus, the 
environment in that area will have already been disturbed by the pre-
construction work the DOE EA considered, which is not part of the NRC 
proposed action, and by the work requiring NRC authorization but that 
the DOE EA considered. Some of the work encompassed by the NRC proposed 
action is not considered by the DOE EA, but the staff finds is similar 
in nature to work considered by the DOE EA. To the extent that the 
nature of the work is similar to the work considered in the DOE EA, the 
NRC staff determined that the effects determination from the DOE EA 
would bound this work. With regard to the work not considered by the 
DOE EA which is dissimilar to work the DOE EA considered (e.g. the 
installation of an SSC within a building as opposed to the construction 
of the building), the NRC staff determined that this work would not 
involve any ground disturbing activities. Further, any impacts from 
hydrologic alteration of groundwater or surface water during the 
authorized activities would be short-term and minor because the major 
hydrological impacts would be expected during the conduct of earthwork, 
dewatering, excavation and backfill, and supporting infrastructure 
activities analyzed in the DOE EA, not the installation components 
within buildings. Therefore, due to the nature of the work and the fact 
that the area would be previously disturbed by the work considered in 
the DOE EA, the NRC staff finds the effects on the environment by the 
work that would be authorized by this exemption, if approved, bounded 
by the analysis in the DOE EA and, therefore, minor.
    In conclusion, the NRC staff has determined that the impacts of the 
proposed exemption on the environment would be minor. Finally, the NRC 
staff notes that although the DOE EA sometimes describes what it 
analyzed using different words than the NRC typically uses, its 
analysis captured the resource areas that the NRC usually considers in 
its EAs. Therefore, there are no significant non-radiologic 
environmental impacts associated with the proposed action.

Environmental Impacts of the Alternatives to the Proposed Action

    As an alternative to the proposed action, the NRC staff considered 
denial of the proposed action (i.e., the ``no-action'' alternative). If 
the NRC were to deny the exemption request, USO would not be allowed to 
perform the activities covered by this exemption before the CP is 
issued, if appropriate. TerraPower, on behalf of USO, has already 
submitted a CP application for the proposed Kemmerer 1 facility. Should 
the NRC staff approve the CP, this work would still occur, just later 
in the future.

Alternative Use of Resources

    There are no unresolved conflicts concerning alternative uses of 
available resources under the proposed action.

Agencies and Persons Consulted

    The NRC staff did not enter into consultation with any Federal 
agency or with the State of Wyoming regarding the environmental impact 
of the proposed action. The NRC and DOE have a Memorandum of 
Understanding (MOU) related to implementation of the National 
Environmental Policy Act (NEPA) for reactor demonstration projects, 
including the proposed Kemmerer 1. Although the MOU lays out certain 
roles and responsibilities for NRC and DOE, it also acknowledges that 
circumstances may arise where both agencies would be better served by a 
different form of coordination and notes that it does not preclude such 
arrangements. In this instance, DOE has already consulted with relevant 
entities. As discussed in this notice, the NRC staff determined that 
the effects considered in the DOE EA bound the effects of this proposed 
action. The NRC staff independently reviewed the DOE's consultation of 
Federal and state agencies for the proposed action. Based on that 
review and the determination that the DOE EA bounds this proposed 
action, the NRC staff determined there was no need for additional 
consultation. Therefore, the NRC staff relied on the consultation 
activities conducted by DOE documented in its EA, which it

[[Page 19325]]

incorporated by reference earlier in this EA.

III. Finding of No Significant Impact

    TerraPower, on behalf of USO, has requested an exemption that, if 
granted, would modify the definition of construction in 10 CFR 
50.10(a)(1)(iv) to allow USO to proceed with the driving of piles, 
subsurface preparation, placement of backfill, concrete, or permanent 
retaining walls within an excavation, installation of foundations, or 
the in-place assembly, erection, fabrication, or testing of NST SSCs 
the failure of which could cause a reactor scram or actuation of a 
safety-related system that are located on the proposed EI without a 
limited work authorization while the NRC staff continues its review of 
the Kemmerer 1 CP application. The proposed action would not have 
significant adverse radiological or non-radiological impacts. This 
FONSI incorporates by reference the EA in Section II of this notice. 
Based on the EA, the NRC concludes that the proposed action will not 
have a significant effect on the quality of the human environment. 
Accordingly, the NRC has determined not to prepare an environmental 
impact statement for the proposed action.

IV. Availability of Documents

    The documents identified in the following table are available to 
interested persons through ADAMS, as indicated.

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            Document description                 ADAMS Accession No.
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Submittal of the Construction Permit         ML24088A059 (package).
 Application for the Natrium Reactor Plant,
 Kemmerer Power Staton Unit 1, dated March
 28, 2024.
Supplement to Construction Permit            ML24123A242.
 Application for the Natrium Reactor Plant,
 Kemmerer Power Staton Unit 1 Regarding
 Agreement between US SFR Owner, LLC and
 TerraPower, LLC, dated May 2, 2024.
Supplement to Construction Permit            ML24123A243.
 Application for the Natrium Reactor Plant,
 Kemmerer Power Staton Unit 1 Regarding
 Fitness-for-Duty and Security Clarifying
 Information, dated May 2, 2024.
Supplement to Construction Permit            ML24130A181.
 Application for the Natrium Reactor Plant,
 Kemmerer Power Staton Unit 1 Regarding
 Materials of Construction Clarifying
 Information, dated May 9, 2024.
Acceptance for Docketing of Kemmerer Power   ML24135A109.
 Station Unit 1 Construction Permit
 Application by US SFR Owner, LLC, dated
 May 21, 2024.
Exemption Request Associated with            ML24253A023.
 Construction of the Natrium Energy Island
 dated, September 9, 2024.
Exemption Request and Application of         ML25059A093.
 Topical Report NATD-LIC-RPRT-0001-A for
 Construction of the Natrium Energy Island
 at Kemmerer Unit 1, dated February 28,
 2025.
Supplement to Exemption Request and          ML25097A132.
 Application of Topical Report NATD-LIC-
 RPRT-0001-A for Construction of the
 Natrium Energy Island at Kemmerer Unit 1,
 dated April 7, 2025.
Withdrawal of Exemption Request from 10 CFR  ML25119A205.
 51.4 Definition of Construction for
 Construction of the Natrium Energy Island
 at Kemmerer Unit 1, dated April 29, 2025.
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    Dated: May 2, 2025.

    For the Nuclear Regulatory Commission.
Jeremy Bowen,
Director, Division of Advanced Reactors and Non-power Production and 
Utilization Facilities, Office of Nuclear Reactor Regulation.
[FR Doc. 2025-07960 Filed 5-6-25; 8:45 am]
BILLING CODE 7590-01-P