[Federal Register Volume 69, Number 216 (Tuesday, November 9, 2004)]
[Notices]
[Pages 64982-64983]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-24888]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-219]
AmerGen Energy Company, LLC; Oyster Creek Nuclear Generating
Station; Exemption
1.0 Background
AmerGen Energy Company, LLC (the licensee), is the holder of
Facility Operating License No. DPR-16, which authorizes operation of
the Oyster Creek Nuclear Generating Station (OCNGS).
The facility consists of a boiling-water reactor (BWR), located in
Ocean County, New Jersey. The license provides, among other things,
that the facility is subject to all rules, regulations, and orders of
the Nuclear Regulatory Commission (NRC, the Commission) now or
hereafter in effect.
2.0 Request/Action
Title 10 of the Code of Federal Regulations (10 CFR) part 50,
Appendix J, Option B, Section III.B., ``Type B and C Tests,'' states,
in part, that containment leakage tests 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
Specifications (TSs). In this context, ``accident pressure,''
Pa, was previously analyzed to be 35 psig at OCNGS.
Accordingly, for main steam isolation valves (MSIVs), leakage rate
testing is to be done at this peak containment calculated pressure,
i.e., 35 psig.
By letter dated December 23, 2003, the licensee requested a
permanent exemption from the requirements of the subject provision of
Appendix J, such that the MSIVs may be tested at lower pressures but
not lower than 20 psig. By separate application also dated December 23,
2003, the licensee proposed to revise the OCNGS TSs, Section 4.5.D, to
specify the lower test pressure and leakage rate; the NRC staff will
communicate the results of its review of this proposed license
amendment by separate correspondence.
In summary, in order for the NRC staff to approve the lower leakage
rate test pressure for the TSs, the licensee first needs an exemption
from the subject regulation.
3.0 Discussion
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. These circumstances include
situations where the regulation would not serve the underlying purpose
of the rule.
OCNGS has two main steam lines, each having two MSIVs. The MSIVs
are 24-inch angled globe valves of ``Y'' configuration. The cup-shaped
poppet moves on a centerline that is 45 degrees upward from the
horizontal centerline of the piping run. Each MSIV is oriented to
provide effective sealing in the direction of post-accident containment
atmosphere leakage, i.e., the forward direction, as compared to the
between-the-valve Type C test which tends to unseat the inboard valve.
The design of the steam lines is such that the preferred method of Type
C testing is through the use of a between-the-valves test tap. Periodic
Type C testing verifies that the leakage assumed in the radiological
analysis is not exceeded. The licensee is requesting this exemption and
associated amendment to the TSs in order to reduce the probability of
lifting the inboard MSIVs during testing. Testing of the two MSIVs
simultaneously at Pa, by pressurizing between the valves
tends to lift the disc of the inboard valve. This results in test
results which may not accurately reflect the isolation capabilities of
the MSIVs. Therefore, testing the two MSIVs simultaneously at
Pa does not serve the underlying purpose of the rule.
In conjunction with the proposed exemption, the licensee proposed
an amendment to the TSs, specifying testing at a minimum of 20 psig
between the 2 MSIVs, and an acceptance pathway leakage rate of 11.9
standard cubic feet per hour. The proposed 20 psig pressure is greater
than one-half of Pa, and the licensee stated that it would
avoid lifting the disc of the inboard valve. As shown in the OCNGS
Updated Final Safety Analysis Report, Figure 6.2-3, the primary
containment pressure following a design-basis loss-of-coolant accident
reaches its peak within 2 to 3 seconds, and rapidly drops below 20
psig. The NRC staff has previously approved testing of MSIVs at reduced
pressure at many other BWR plants. Industry experience in testing these
valves at a pressure in the range of 20 psig and with an acceptance
criterion of approximately 11.9 standard cubic feet per hour has been
shown to be effective in determining the condition of these valves.
The underlying purpose of the requirements of 10 CFR part 50,
Appendix J, Option B, Section III.B is to demonstrate by periodic
testing that the primary reactor containment will be able to perform
its function of providing a leak-tight barrier against uncontrolled
release of radioactivity to the environment. As stated above, the NRC
staff examined the licensee's rationale to support the exemption and
concluded that MSIV leakage testing at accident pressure does not serve
the underlying purpose of the rule, and fulfillment of the proposed
alternative testing criteria would demonstrate leak-tightness of the
MSIVs. Thus, the underlying purpose of the subject regulation is
achieved and served by the licensee's proposed criteria.
Based upon a consideration of the information submitted by the
licensee, the NRC staff concludes that the licensee's proposed reduced
test pressure for Type C testing of MSIVs is justified.
Therefore, the NRC staff concludes that pursuant to 10 CFR
50.12(a)(2), special circumstances are present in that application of
the Appendix J
[[Page 64983]]
requirements does not serve the underlying purpose of the rule.
4.0 Conclusion
Accordingly, the Commission has determined that, pursuant to 10 CFR
50.12(a), 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 Commission hereby grants the licensee an exemption from
the requirements of 10 CFR part 50, Appendix J, Option B, Section III.B
for OCNGS. Specifically, this permanent exemption permits the licensee
to perform leakage testing of the MSIVs at reduced pressure, but not
lower than 20 psig.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will not have a significant effect on the
quality of the human environment (69 FR 63562).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 2nd day of November, 2004.
For the Nuclear Regulatory Commission.
Ledyard B. Marsh,
Director, Division of Licensing Project Management, Office of Nuclear
Reactor Regulation.
[FR Doc. 04-24888 Filed 11-8-04; 8:45 am]
BILLING CODE 7590-01-P