[Federal Register Volume 91, Number 28 (Wednesday, February 11, 2026)]
[Notices]
[Pages 6269-6271]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2026-02770]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-410; NRC-2026-0199]
Constellation Energy Generation, LLC; Nine Mile Point Nuclear
Station, Unit 2; Exemption
AGENCY: Nuclear Regulatory Commission.
ACTION: Notice; issuance.
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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) issued an
exemption in response to a request dated January 29, 2025, as
supplemented on June 9, 2025, from Constellation Energy Generation,
LLC, that authorizes leak rate testing of the main steam isolation
valves at a pressure lower than the calculated peak containment
internal pressure related to the Nine Mile Point, Unit 2, design basis
accident loss-of-coolant accident as specified in the Technical
Specifications.
DATES: The exemption was issued on February 3, 2026.
ADDRESSES: Please refer to Docket ID NRC-2026-0199 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-2026-0199. 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 ADAMS Public 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
at [email protected]. The exemption request, dated January 29, 2025,
is available in ADAMS under Accession No. ML25029A181.
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: Richard V. Guzman, Office of Nuclear
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC
20555-0001; telephone: 301-415-1030; email: [email protected].
SUPPLEMENTARY INFORMATION: The text of the exemption is attached.
Dated: February 9, 2026.
For the Nuclear Regulatory Commission.
Richard Guzman,
Senior Project Manager, Plant Licensing Branch I, Division of Operating
Reactor Licensing, Office of Nuclear Reactor Regulation.
Attachment--Exemption
NUCLEAR REGULATORY COMMISSION
Docket No. 50-410
Constellation Energy Generation, LLC
Nine Mile Point Nuclear Station, Unit 2
Exemption
I. Background
Constellation Energy Generation, LLC (CEG, the licensee), is the
holder of Renewed Facility Operating License No. NPF-69, which
authorizes operation of the Nine Mile Point Nuclear Station (Nine
Mile Point), Unit 2, a boiling-water reactor located in Scriba, New
York (6 miles northeast of Oswego, New York). The license provides,
among other things, that the facility is subject to all rules,
regulations, and orders of the U.S. Nuclear Regulatory Commission
(NRC, Commission) now or hereafter in effect.
[[Page 6270]]
II. Request/Action
By application dated January 29, 2025 (ML25029A181), as
supplemented on June 9, 2025 (ML25155B825), the licensee, pursuant
to 10 CFR 50.12, ``Specific exemptions,'' requested an exemption
from the requirements of Title 10 of the Code of Federal Regulations
(10 CFR), Part 50, Appendix J, Paragraph III.C.2 to allow leak rate
testing of the main steam isolation valves (MSIVs) at a reduced test
pressure for Nine Mile Point, Unit 2. The licensee stated that
continued compliance results in undue costs, and increased dose and
industrial hazards that are significantly more than those incurred
by other similarly situated plants. The application also requested a
license amendment to revise Technical Specification (TS) 3.6.1.3,
``Primary Containment Isolation Valves (PCIVs),'' Surveillance
Requirement (SR) 3.6.1.3.12, to reduce the MSIV test pressure and
the associated maximum allowable leakage limit for Nine Mile Point,
Unit 2. The license amendment request is addressed separately.
The regulation at 10 CFR 50.54(o) requires primary reactor
containments for water-cooled power reactors, other than those for
which the certifications required under 10 CFR 50.82(a)(1) or
52.110(a)(1) have been submitted, to meet the requirements of
Appendix J to 10 CFR part 50, ``Leakage Rate Testing of Containment
of Water-Cooled Nuclear Power Plants.'' Appendix J establishes
containment leakage test requirements, schedules, and acceptance
criteria for verifying the leak-tight integrity of the primary
reactor containment and systems and components that penetrate the
containment. Appendix J provides two options for meeting this
requirement: Option A and Option B. In 1996 the NRC staff approved a
request for the then-licensee to follow Option B. (ML011140067).
As an initial matter, the NRC staff notes that the licensee
requested an exemption from Paragraph III.C.2 but that Option B does
not have a Paragraph III.C.2. Option A, however, does have a
Paragraph III.C.2. The equivalent Option B requirement is found in
Option B, Paragraph III.B. As the licensee follows Option B, the NRC
staff cannot grant the licensee an exemption from an Option A
requirement. Consequently, the NRC staff is, on its own initiative,
considering granting the licensee an exemption from Option B,
Paragraph III.B. Given that the two provisions require the same test
and the exemption does not affect the portions of the provisions
that are different, the NRC staff further notes that this exemption
is substantively identical to the requested exemption. This change
does not change the underlying analysis; it only affects provision
from which the exemption is granted. As such, the NRC staff is
relying on the analysis the licensee submitted to support the
original exemption request.
As described in Option B, Paragraph I, the purposes of these
tests are to ensure that (1) leakage through these containments or
systems and components penetrating these containments does not
exceed allowable leakage rates specified in the technical
specifications, and (2) integrity of the containment structure is
maintained during its service life. Option B, Paragraph III.B of 10
CFR part 50, Appendix J, requires licensees to perform Type C
pneumatic tests to measure containment isolation valve leakage rates
to ensure the integrity of the overall containment system as a
barrier to fission product release to reduce the risk from reactor
accidents. The MSIVs are a type of containment isolation valve. The
tests required by Option B, Paragraph III.B must demonstrate that
the sum of the leakage rates at accident pressure of Type B tests,
and pathway leakage rates from Type C tests, is less than the
performance criterion (La) with margin, as specified in the
Technical Specification. Option B, Paragraph II defines La as the
maximum allowable leakage rate at pressure Pa as specified in the
Technical Specifications. Option B, Paragraph II, defines Pa as the
calculated peak containment internal pressure related to the design
basis loss-of-coolant accident as specified in the Technical
Specifications. This exemption, if granted, would, in effect, allow
the licensee to perform the Type C tests for the MSIVs at the
requested reduced pressure rather than at Pa. According to the
licensee, testing at the reduced pressure allows the test conditions
to be reliably established while maintaining conservatism in the
measurement of valve leakage.
The technical analysis necessary to support the proposed change
to associated surveillance requirement (TS SR 3.6.1.3.12) and the
associated maximum allowable leakage limit for Nine Mile Point, Unit
2 is documented in a separate safety evaluation for the related
license amendment request (ML26008A004).
III. Discussion
Pursuant to 10 CFR 50.12(a), the Commission may, upon
application by any interested person or upon its own initiative,
grant exemptions from the requirements of 10 CFR part 50 when (1)
the exemptions are authorized by law, will not present an undue risk
to the public health and safety, and are consistent with the common
defense and security and (2) special circumstances are present.
Under 10 CFR 50.12(a)(2), special circumstances are present when at
least one of the following six conditions are met:
(i) Application of the regulation in the particular
circumstances conflicts with other rules or requirements of the
Commission; or
(ii) Application of the regulation in the particular
circumstances would not serve the underlying purpose of the rule or
is not necessary to achieve the underlying purpose of the rule; or
(iii) Compliance would result in undue hardship or other costs
that are significantly in excess of those contemplated when the
regulation was adopted, or that are significantly in excess of those
incurred by others similarly situated; or
(iv) The exemption would result in benefit to the public health
and safety that compensates for any decrease in safety that may
result from the grant of the exemption; or
(v) The exemption would provide only temporary relief from the
applicable regulation and the licensee or applicant has made good
faith efforts to comply with the regulation; or
(vi) There is present any other material circumstance not
considered when the regulation was adopted for which it would be in
the public interest to grant an exemption. If such condition is
relied on exclusively for satisfying the special circumstances
requirement, the exemption may not be granted under the Executive
Director for Operations has consulted with the Commission.
A. The Exemption Is Authorized by Law
If granted, the exemption would authorize leak testing of the
MSIVs at a pressure lower than the calculated peak containment
internal pressure related to Nine Mile Point, Unit 2's design basis
accident loss-of-coolant accident as specified in the Technical
Specifications (Pa). Pursuant to 10 CFR 50.12(a), the NRC may grant
exemptions from the requirements of 10 CFR part 50, including
Appendix J, when the exemptions are authorized by law. An exemption
is authorized by law when it is not expressly prohibited by statute
or regulation. The NRC staff has determined that no provisions in
law expressly prohibit or otherwise restrict the NRC staff from
granting the exemption. Accordingly, the NRC staff concludes that
the exemption is authorized by law.
B. The Exemption Presents No Undue Risk to Public Health and Safety
Type C pneumatic tests used to measure containment isolation
valve leakage rates, including MSIVs, are performed to verify the
integrity of the overall containment system as a barrier to fission
product release and to reduce the risk associated with postulated
reactor accidents. The Nine Mile Point, Unit 2 MSIVs are designed
with an angled orientation in the main steam lines to enhance
sealing capability in the direction of postulated accident
conditions. Testing between the MSIVs is an NRC-acceptable testing
method and provides conservative results. Testing the inboard valve
in the reverse direction is conservative because the direction of
pressurization applies a force opposite to the valve seating forces.
In addition, due to the orientation of the MSIVs, testing the
outboard valves in the direction of postulated accident conditions
results in pressurization forces that act in the direction of the
valve seating forces and, therefore, provide enhanced sealing. These
are the directions in which the Nine Mile Point, Unit 2 inboard and
outboard MSIVs are tested.
As seen in non-public operating experience, testing of the
inboard and outboard MSIVs by pressurizing the volume between the
valves at full test pressure lifts the disc of the inboard valve,
due to the orientation of the inboard MSIV, resulting in a
meaningless test. By pressurizing the volume between the valves at a
reduced pressure of greater than or equal to 25 psig, lifting the
disc of the inboard valve is avoided. Based on the above-mentioned
operating experience, this approach ensures a satisfactory test of
the outboard MSIV in the same direction as under LOCA conditions to
confirm that the leak rate is within the maximum pathway leakage
conditions. Based on its technical judgement, the NRC staff
determined that this operating experience is
[[Page 6271]]
relevant here because it involves the same types of valves with this
orientation. In its exemption request, the licensee stated that when
leak rate testing is performed at a reduced pressure, it would
conservatively assign the total measured leakage through both valves
to the penetration. This is conservative because it means the
licensee will assign the combined leakage value to each valve,
leading to a higher measured leakage than if both valves were
measured separately and had their individual leakages assigned to
them. Further, this procedure is consistent with the TS surveillance
requirement, which the NRC staff reviewed in the related license
amendment request mentioned above.
Therefore, based on the above, the proposed exemption to allow
MSIV leak rate testing at a reduced pressure enables the licensee to
obtain valid and reliable test results while maintaining a
conservative determination of leakage through the valves. Therefore,
the NRC staff finds that conducting MSIV leak rate testing at a
reduced test pressure of greater than or equal to 25 psig ensures
the operability of the MSIVs and their capability to maintain
containment isolation integrity under postulated accident
conditions. Accordingly, based on the considerations discussed
above, the NRC staff concludes that the proposed exemption would not
result in an undue risk to the public health and safety.
C. The Exemption Is Consistent With the Common Defense and Security
As discussed above, the exemption would permit leak testing of
the MSIVs at a pressure lower than the calculated peak containment
pressure. This change in MSIV test pressure is not related to
security considerations. The exemption would not alter any site
security features, procedures, staffing, or other security-related
matters. Therefore, the exemption does not affect the common defense
and security, and the NRC staff concludes that the exemption is
consistent with the common defense and security.
D. Special Circumstances
The regulation under 10 CFR 50.12(a)(2) states, in part, that
``[t]he Commission will not consider granting an exemption unless
special circumstances are present,'' and describes, in 10 CFR
50.12(a)(i) through (vi), the conditions under which special
circumstances exist. In Section II of the licensee's exemption
request, the licensee stated that two of the six special
circumstances listed in 10 CFR 50.12(a)(2) are applicable to the
exemption, as follows:
10 CFR 50.12(a)(2)(ii): Application of the regulation
in the particular circumstances would not serve the underlying
purpose of the rule or is not necessary to achieve the underlying
purpose of the rule.
10 CFR 50.12(a)(2)(iv): The exemption would result in
benefit to the public health and safety that compensates for any
decrease in safety that may result from the grant of the exemption;
The underlying purpose of 10 CFR part 50, Appendix J, Option B
is to ensure that (a) leakage through these containments or systems
and components penetrating these containments does not exceed
allowable leakage rates specified in the technical specifications;
and (b) integrity of the containment structure is maintained during
its service life.
Operating experience has shown that, due to the orientation of
the MSIVs, testing at the inboard and outboard valves simultaneously
at Pa by pressurizing the volume between the valves does not
accurately reflect the isolation capabilities of the valves. The
inability to achieve proper testing conditions when pressurizing
between the inboard and outboard valves at Pa necessitates
reperforming the leak rate testing. This is done by conducting the
tests in the accident direction at Pa to accurately evaluate
individual valve performance which leads to additional occupational
radiation exposure.
In contrast, non-public industry operating experience, discussed
when assessing whether there is an undue risk to public health and
safety, has demonstrated that simultaneous testing of the inboard
and outboard MSIVs by pressurizing the volume between the valves at
a reduced pressure of 25 psig is effective in establishing proper
test conditions. This means that testing at 25 psig is sufficient to
ensure that (a) leakage through these containments or systems and
components penetrating these containments does not exceed allowable
leakage rates specified in the technical specifications; and (b)
integrity of the containment structure is maintained during its
service life. Therefore, requiring the MSIV test pressure at Pa is
not necessary to achieve the underlying purpose of the 10 CFR part
50, Appendix J.
Because compliance with the requirement to perform MSIV leak
rate testing at the peak calculated containment internal pressure is
not necessary to achieve the underlying purpose of the rule, the NRC
staff finds that the special circumstances specified in 10 CFR
50.12(a)(2)(ii) are present. Accordingly, the NRC staff concludes
that special circumstances exist to support the granting of the
exemption. Since the presence of one special circumstance is
sufficient to support the granting of an exemption under 10 CFR
50.12(a)(2), the NRC staff did not further evaluate whether the
special circumstances described in 10 CFR 50.12(a)(2)(iv) are
present.
E. Environmental Considerations
A categorical exclusion for inspection and surveillance
requirements is provided in 10 CFR 51.22(c)(25)(vi)(C), provided
that the criteria in 10 CFR 51.22(c)(25)(i) through (v) are
satisfied. In its review of the exemption request, and for the
reasons discussed when concluding that there would be no undue risk
to the public health and safety, the NRC staff determined that,
pursuant to 10 CFR 51.22(c)(25), granting the exemption: (i) does
not involve a significant hazards consideration because it does not
result in a significant reduction in a margin of safety, create the
possibility of a new or different kind of accident from any accident
previously evaluated, or involve a significant increase in the
probability or consequences of an accident previously evaluated;
(ii) would not result in a significant change in the types or
significant increase in the amounts of effluents that may be
released offsite, because the exemption does not alter or create
additional pathways for effluent release; (iii) would not result in
a significant increase in individual or cumulative occupational or
public radiation exposure, because the exemption does not introduce
new or increased radiological hazards; (iv) would not result in
significant construction impacts, because the exemption does not
involve construction activities; and (v) would not increase the
potential for or consequences of radiological accidents. Based on
the above, NRC determined that the exemption meets the eligibility
criteria for the categorical exclusion set forth in 10 CFR
51.22(c)(25). Therefore, in accordance with 10 CFR 51.22(b), no
environmental impact statement or environmental assessment need be
prepared in connection with this exemption request.
IV. Conclusions
Accordingly, the NRC staff has determined that, pursuant to 10
CFR 50.12, the exemption is authorized by law, will not present an
undue risk to the public health and safety, and is consistent with
the common defense and security. Also, special circumstances are
present. Therefore, the NRC staff hereby grants CEG an exemption
from the requirement of 10 CFR part 50, Appendix J, Option B,
Paragraph III.B to allow leak rate testing of the MSIVs at a reduced
test pressure at Nine Mile Point, Unit 2.
This exemption is effective upon issuance.
Dated: February 3, 2026.
For the Nuclear Regulatory Commission.
/RA/
Aida Rivera-Varona, Acting Director, Division of Operating Reactor
Licensing, Office of Nuclear Reactor Regulation.
[FR Doc. 2026-02770 Filed 2-10-26; 8:45 am]
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