[Federal Register Volume 59, Number 38 (Friday, February 25, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4297]
[[Page Unknown]]
[Federal Register: February 25, 1994]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-352]
Philadelphia Electric Company (Limerick Generating Station, Unit
1)
Exemption
I
Philadelphia Electric Company (the licensee), is the holder of
Facility Operating License No. NPF-39, which authorizes operation of
the Limerick Generating Station (LGS), Unit 1. The license provides,
among other things, that the licensee is subject to all rules,
regulations, and orders of the Nuclear Regulatory Commission (the
Commission) now and hereafter in effect.
The LGS, Unit 1 facility consists of a boiling water reactor
located in Chester and Montgomery Counties, Pennsylvania.
II
In its letter dated November 30, 1993, the licensee requested an
exemption from the Commission's regulations. The subject exemption is
from a requirement in appendix J to 10 CFR part 50 that a set of three
Type A tests (Containment Integrated Leakage Rate Tests, or CILRTs) be
performed, at approximately equal intervals, during each 10-year
service period. The exemption applies to the first 10-year service
period; subsequent service periods are not changed. In the same letter,
the licensee applied for an amendment to Operating License No. NPF-39
to change certain provisions of the LGS Technical Specifications (TSs).
The type A test is defined in 10 CFR part 50, appendix J, section
II.F, as ``tests intended to measure the primary reactor containment
overall integrated leakage rate (1) after the containment has been
completed and is ready for operation, and (2) at periodic intervals
thereafter.'' The 10-year service period begins with the inservice
date. The first CILRT testing interval was 36 months, and the second
was 39 months. The time interval between CILRTs should be about 40
months based on performing three such tests at approximately equal
intervals during each 10-year service period.
The request for a one-time exemption would allow the third Type A
CILRT within the first 10-year service period to be conducted during
the sixth refueling outage. This requested exemption is a one-time
schedular extension of the third interval to 65 months. It does not
affect the second 10-year service period.
With respect to the subject exemption request, the NRC staff notes
that the first and second CILRTs of the set of three tests for the
first 10-year service period for LGS were conducted in August 1987 and
November 1990. The third of the first set of three CILRTs will be
scheduled for Refueling Outage 6, projected to start in January 1996,
pending approval of the exemption request. The current third test
period in the first 10-year service period will actually be exceeded by
approximately 15 months.
Data from the first August 1989 and second November 1990 CILRT at
LGS, Unit 1 indicates that most of the measured leakage is from the
containment penetrations and not from the containment barrier. The
``as-left'' leakage rate was well below the 10 CFR part 50 Appendix J
limit. Both Appendix J and the TS require that the leakage rate be less
than 75% of La to allow for deterioration in leakage paths between
tests. The allowable leakage rate, La, is 0.5 wt.%/day. Therefore,
the established acceptable limit is <0.375 wt.%/day. The ``as-left''
leakage rates for the first two CILRTs were 0.178 and 0.334 wt.%/day,
which is below the acceptance limit. The Type B and C test (Local
Leakage Rate test or LLRT) program also provides assurance that
containment integrity has been maintained. LLRTs demonstrate
operability of components and penetrations by measuring penetration and
valve leakage. Additionally, there have been no modifications made to
the plant that could adversely affect the test results.
The licensee further notes that the performance of a fourth test in
the first 10-year service period to meet the requirements of the TSs
and Appendix J would result in additional radiation exposure to
personnel. Omitting the test will result in additional dose savings by
eliminating contamination and by reducing exposure from venting and
draining and from setups and restorations of instrumentation required
to perform the test. These factors and the costs associated with a
fourth test for a 15-month difference in interval time are not offset
by the benefits of the fourth test.
For the reasons set forth above, the NRC staff concludes that this
deviation from the 10-year service period ending August 1994 is not
significant in terms of complying with the safety or scheduling
requirements of Section III.D.1.(a) of Appendix J. Accordingly, the
staff finds that the additional test would not provide substantially
different information and that the intent of Appendix J is met.
Therefore, the subject exemption request meets the special
circumstances of 10 CFR 50.12(a)(2)(ii), in that the fourth test is not
necessary to achieve the underlying purpose of the rule.
On this basis, the NRC staff finds that the licensee has
demonstrated that special circumstances are present as required by 10
CFR 50.12(a)(2). Further, the staff also finds that extending the
service period will not present an undue risk to the public health and
safety; since the licensee has justified the leaktight integrity of the
containment based on previous leakage test results, the staff concludes
that a one-time extension of approximately 15 months beyond the maximum
permitted third test interval within the first 10-year service period
will not have a significant safety impact.
III
Accordingly, the Commission has determined that, pursuant to 10 CFR
50.12, an exemption is authorized by law and will not endanger life or
property or the common defense and security and is otherwise in the
public interest and hereby grants the following exemption with respect
to a requirement of 10 CFR part 50, appendix J, Section III.D.1(a):
For the Limerick Generating Station, Unit 1, the current third test
period within the first 10-year service period may be extended by
approximately 15 months, so that the third periodic Type A test may be
performed during the Sixth refueling outage scheduled for January,
1996.
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 (59 FR 5785).
This exemption is effective upon issuance.
For the Nuclear Regulatory Commission.
Dated at Rockville, Maryland this 16 day of February 1994.
Gus C. Lainas,
Acting Director, Division of Reactor Projects - I/II, Office of Nuclear
Reactor Regulation.
[FR Doc. 94-4297 Filed 2-24-94; 8:45 am]
BILLING CODE 7590-01-M