[Federal Register Volume 64, Number 250 (Thursday, December 30, 1999)]
[Notices]
[Pages 73593-73594]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-33970]
[[Page 73593]]
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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-269, 50-270, and 50-287]
In the Matter of Duke Energy Corporation (Oconee Nuclear Station,
Units 1, 2, and 3); Exemption
I
The Duke Energy Corporation (Duke/the licensee) is the holder of
Facility Operating License Nos. DPR-38, DPR-47, and DPR-55, that
authorize operation of the Oconee Nuclear Station, Units 1, 2, and 3
(Oconee), respectively. The licenses provide, among other things, that
the facilities are subject to all rules, regulations, and orders of the
U.S. Nuclear Regulatory Commission (the Commission) now or hereafter in
effect.
The facilities consist of three pressurized water reactors located
on Duke's Oconee site in Seneca, Oconee County, South Carolina.
II
Title 10 of the Code of Federal Regulations (10 CFR) Part 50,
Appendix J, contains the following requirements:
a. Section III.D.2(b)(i) requires that air locks be tested prior to
initial fuel loading and at 6-month intervals thereafter at an internal
pressure not less than Pa (the calculated peak containment
internal pressure related to the design basis accident).
b. Section III.D.2(b)(ii) requires that air locks opened during
periods when containment integrity is not required shall be tested at
the end of such periods at Pa.
c. Section III.D.2(b)(iii) requires that air locks opened during
periods when containment integrity is required shall be tested within 3
days after being opened. For air locks opened more frequently than once
every 3 days, the air lock shall be tested at least once every 3 days
during the period of frequent openings. For air lock doors having
testable seals, testing the seals fulfills the 3-day test requirement.
III
The proposed action is in accordance with the licensee's
application for exemption contained in a submittal dated October 5,
1999.
Whenever the plant is in cold shutdown (Mode 5) or refueling (Mode
6), containment integrity is not required. However, if an airlock is
opened when in Modes 5 or 6 (which is usually the case), 10 CFR 50,
Appendix J, Section III.D.2(b)(ii) requires that an overall air lock
leakage test at not less than Pa be performed before plant
heatup and startup (i.e., before Mode 4 is entered). The licensee has
requested an exemption that would allow this test requirement to be met
by performing an air lock door seal leakage test per 10 CFR 50,
Appendix J, Section III.D.(b)(iii) during plant startup prior to
entering Mode 4 if no maintenance has been performed on the air lock
that could affect its sealing capability. If maintenance has been
performed that could affect its sealing capability, an overall air lock
leakage test per 10 CFR 50, Appendix J, Section III.D.2(b)(ii) would be
necessary prior to establishing containment integrity.
The existing air lock doors are designed so that the air lock
pressure test can only be performed after a strongback (structural
bracing) has been installed on the inner door, since the pressure used
to perform the test is opposite that of accident pressure and would
tend to unseat the door. Performing the full air lock test in
accordance with the present requirements takes approximately 12 hours,
since it requires installation of the strongback, performing the test,
and removing the strongback. During the test, access through the air
lock is prohibited, which, therefore, requires evacuation of personnel
from the containment or the personnel must remain inside the
containment during the test until Mode 4 is reached. The licensee has
determined that pressurizing the volume between the seals to 60 pounds
per square inch gauge pressure after each opening, and prior to
establishing containment integrity, provides the necessary surveillance
to ensure the sealing capability of the door seals.
If the periodic 6-month test of 10 CFR 50, Appendix J, Section
III.D.(b)(i) and the test required by 10 CFR 50, Appendix J, Section
III.D.(b)(iii) are current, no maintenance has been performed on the
air lock that could affect its sealing capability, and the air lock is
properly sealed as determined by the seal test, there is no reason to
expect that the air lock will leak just because it has been opened in
Modes 5 or 6. Therefore, there is no impact on plant operation or
safety. In addition, due to the design of the air lock, the 6-month
test should detect air lock deterioration.
IV
Pursuant to 10 CFR 50.12, 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 public health or
safety, and are consistent with the common defense and security; and
(2) when special circumstances are present. This is also consistent
with the determination that the staff has reached for other licensees
under similar conditions based on the same considerations.
Accordingly, the staff concludes that the licensee's proposed
approach of substituting the 3-day seal leakage test requirements of 10
CFR 50, Appendix J, Section III.D.(b)(iii) for the full pressure test
of 10 CFR 50, Appendix J, Section III.D.(b)(ii) is acceptable when no
maintenance that could affect the sealing capability has been performed
on the air lock. Whenever maintenance that could affect the sealing
capability has been performed on the air lock, the full pressure test
requirements of 10 CFR 50, Appendix J, Section III.D.(b)(ii) must still
be met.
Therefore, the staff concludes that requesting the exemption under
the special circumstances of 10 CFR 50.12(a)(2)(ii) is appropriate and
that application of the regulation is not necessary to serve the
underlying purpose of the rule. The underlying purpose of the rule is
to ensure that: (a) leakage through the primary containment, and
systems and components penetrating the primary containment, does not
exceed the allowable leakage rate values specified in the Technical
Specifications or associated Bases; and (b) periodic surveillance of
containment penetrations and isolation valves, and systems and
components penetrating the containment, is performed so that proper
maintenance and repairs are made during the service life of the
containment.
V
Accordingly, the Commission has determined that, pursuant to 10 CFR
50.12(a), the exemption is authorized by law, will not endanger life or
property or common defense and security, and is, otherwise, in the
public interest. Therefore, the Commission hereby grants Duke an
exemption from the requirements of 10 CFR Part 50, Appendix J, Section
III.D.2(b)(ii) for containment air lock tests as described above, for
the Oconee Nuclear Station, Units 1, 2, and 3.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will not result in any significant effect on
the quality of the human environment (64 FR 70072).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 23rd day of December 1999.
[[Page 73594]]
For the Nuclear Regulatory Commission.
John A. Zwolinski,
Director, Division of Licensing Project Management, Office of Nuclear
Reactor Regulation.
[FR Doc. 99-33970 Filed 12-29-99; 8:45 am]
BILLING CODE 7590-01-P