[Federal Register Volume 60, Number 85 (Wednesday, May 3, 1995)]
[Notices]
[Pages 21833-21835]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-10887]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-416]
Entergy Operations Inc., (Grand Gulf Nuclear Station, Unit No.
1); Exemption
I
Entergy Operations, Inc., (the licensee) is the holder of Facility
Operating License No. NPF-29, which authorizes operation of the Grand
Gulf Nuclear Station, Unit 1. The operating license provides, among
other things, that the licensee is subject to all rules, regulations,
and orders of the Commission now and hereafter in effect.
The facility consists of a boiling water reactor at the licensee's
site in Claiborne County, Mississippi.
II
By letter dated August 13, 1993, as supplemented by letters dated
April 15, May 11, June 24, and July 20, 1994, and April 18, 1995,
pursuant to 10 CFR 50.12(a), Entergy Operations Inc. requested an
exemption to Sections III.D.1(a), III.D.2, III.D.2(b)(i),
III.D.2.(b)(iii) and III.D.3 of 10 CFR Part 50, Appendix J, to permit
the selection of containment leakage rate testing intervals for
components on the basis of performance.
Although the staff had issued an Advanced Notice of Proposed Rule
Making to revise Appendix J on November 24, 1992 (57 FR 55156), the
licensee stated in the August 13, 1993, submittal that the ``plant
specific needs [[Page 21834]] of Grand Gulf'' would best be met by a
plant specific submittal. The staff agreed to review the licensee's
proposal in the context of the ongoing rulemaking activities. In SECY
94-036, dated February 17, 1994, the staff informed the Commission that
it would review the Grand Gulf proposal because of its potential
usefulness in the rulemaking process due to its scope and the technical
information it provides. Testing methods were not included in the scope
of the licensee's proposal. The licensee proposed changes to the
frequency of testing only. The staff has reviewed the licensee's
proposed exemption. The staff's safety evaluation is enclosed.
III
The licensee proposed changes to the frequency of performing Type
A, B, and C tests including changes to the frequency of leakage rate
testing of air locks. The test frequencies will be determined
individually for each component based on previous performance. The
licensee presented plant specific data and plant specific risk analyses
to support the proposed changes. In addition to information supplied by
the licensee, the staff, in reviewing this exemption request, utilized
technical information available from the on-going Appendix J
rulemaking, including NUREG-1493 ``Performance-Based Containment Leak-
Test Program'', dated December 1994. This rulemaking will also revise
the frequency of leakage rate testing so that the intervals between
tests is a function of individual component performance.
Because an Appendix J rulemaking is in progress, this exemption
shall be valid until startup following Refueling Outage 9.
IV
A Type A test assures that the overall or integrated leakage rate
from the whole containment is below the acceptance criterion specified
in Appendix J. This exemption does not change this value. Appendix J
presently specifies the test frequency for a Type A test as a set of
three tests, at approximately equal intervals during each 10-year
service period. The licensee proposes to change the test frequency to
one Type A test in 10 years. Both an analysis of the test results from
operating reactors over an extended period (NUREG-1493) and a risk
analysis (EPRI TR-104285, ``Risk Impact Assessment of Revised
Containment Leak Rate Testing Intervals'') support extending the Type A
test interval to once in 10 years.
The staff proposed that the exemption include a precondition before
extending the Type A test. Two consecutive Type A tests must be
successful before the interval is extended. This is included in the
exemption. By letter dated April 18, 1995, the licensee agreed to this
change. The following exemption is granted until startup from Refueling
Outage (RFO) 9, currently scheduled for Spring 1998.
Exemption From Section III.D.1(a)
Type A tests shall be performed on a 10-year interval provided that
the two previous consecutive Type A tests, performed on the test
interval specified in Appendix J (three tests, at approximately equal
intervals in a 10-year period), have been successful.
If a Type A test is failed, and the failure is not due to a Type B
or C component, acceptable performance must be reestablished by
performing a Type A test within 48 months of the unsuccessful Type A
test. Following a successful Type A test, the surveillance frequency
may be returned to once per 10 years.
In addition, the licensee must perform general inspections of the
accessible interior and exterior surfaces of the containment
structures, as specified in Section V.A of Appendix J, at the test
interval specified in Appendix J for Type A tests, even when no Type A
test is required during that outage. By letter dated April 18, 1995,
the licensee agreed to this change.
There is no relationship between Type A testing and the inservice
inspection (ISI) service period. This exemption will continue in effect
until startup from RFO 9.
V
The licensee proposed an exemption from Sections III.D.2(a) and
III.D.3 of Appendix J to permit Type B and C testing to be done based
on previous performance of a component. The licensee presented data and
analyses to show that the risk from using a performance-based approach
to Type B and C testing is negligible. This is in agreement with the
conclusions of NUREG-1493.
The licensee proposed that the test interval be determined as
follows: (1) One successful test or a failure would require maintaining
the present test interval of 2 years. (2) Two successful consecutive
tests would permit extending the test interval to five years. (3) Three
successful consecutive tests would result in increasing the test
interval to 10 years. The staff does not agree with a 10-year interval.
It is the staff's judgment that the licensee has not justified the 10-
year interval to the same degree of confidence as the 5-year interval.
By letter dated April 18, 1995, the licensee agreed to this change.
In addition, there are certain valves which the staff considers to
be so safety significant that the test interval for these valves should
not be extended without prior staff review and approval. The staff has
specified these valves in the exemption. By letter dated April 18,
1995, the licensee agreed to this change.
Exemption From Sections III.D.2(a) and III.D.3 of Appendix J
After two successful consecutive tests, performed at the present
Appendix J test interval of no more than 2 years, a Type B or C
component may be tested once every 5 years. If this test or a
subsequent test is a failure, the test interval for this component
shall revert to a 2-year interval until the component passes two
consecutive tests. The 5-year interval may then be resumed. By letter
dated April 18, 1995, the licensee agreed to this change.
Main steam isolation valves, feedwater valves and containment
system supply and exhaust isolation valves shall remain on a 2-year
test interval. Any change will require prior review and approval by the
NRC. This exemption will continue in effect until startup from RFO 9.
VI
The licensee proposed to increase the test intervals for air locks
based on the good performance of the air locks at Grand Gulf. The
licensee's August 13, 1993, submittal provides a summary of test data
which shows excellent performance in both air lock and air lock door
seal testing.
The staff proposed an addition to the requested exemption to
account for the contingency that the performance may not be maintained
at this high level. If an air lock fails a test, the extended interval
would revert to the Appendix J test intervals until two consecutive
successful's tests demonstrate that the problem has been resolved. By
letter dated April 18, 1995, the licensee agreed to this change.
Exemption From Section III.D.2(b)(i) and (b)(iii)
Air locks may be leakage rate tested at intervals of no more than 2
years. If an air lock fails a leakage rate test, the air lock shall
then be required to pass two consecutive leakage rate tests at a test
interval of 6 months prior to returning to the 2-year test interval.
During a period of frequent opening of air lock doors, the air locks
shall be tested at least every 30 days. If an air [[Page 21835]] lock
fails a leakage rate test during a period of frequent opening, the air
lock shall be required to pass two consecutive leakage rate tests at a
test interval of 72 hours prior to returning to the 30-day interval.
Since the Grand Gulf air lock doors have testable seals, testing the
seals fulfills the 30-day test requirement. This exemption will
continue in effect until startup from RFO 9.
VII
The staff's safety evaluation, which is enclosed and summarized
above, concludes that the licensee's proposed extension of Appendix J
test intervals is acceptable. This exemption will remain valid until
startup following Refueling Outage 9. This approval is based on the
assumption that all other aspects of Appendix J testing not explicitly
addressed will be conducted in accordance with Appendix J.
Section 50.12 of Title 10 of the Code of Federal Regulations,
``Specific Exemptions'', delineates the conditions which must be
satisfied in order for the Commission to grant an exemption from the
regulations of 10 CFR Part 50. The proposed exemption must not violate
applicable law, it must not ``present an undue risk to the public
health and safety'', and must be ``consistent with the common defense
and security''. The licensee states that it believes these conditions
are satisfied. The staff concurs.
In addition, 10 CFR 50.12 states that the Commission will not
consider granting an exemption unless special circumstances are
present. The licensee, in the August 13, 1993, submittal presented its
argument as to why this exemption request meets several of the special
circumstances specified in 10 CFR 50.12. It is the staff's opinion that
the licensee's proposal satisfies special circumstance 50.12(a)(2)(iv).
Special circumstance (iv) states that: 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.
It is the staff's judgment that there is a significant public
benefit to be derived from granting the licensee's exemption request to
10 CFR Part 50, Appendix J. The licensee's proposal was detailed and
well thought-out and thoroughly considered the effect on safety of the
proposed changes. Reviewing this exemption request was beneficial to
the staff's Appendix J rulemaking effort. Granting the exemption will
assist the staff in assessing the process of implementing a
performance-based containment leakage rate testing rule which, inturn,
is of a clear benefit to the public. The staff considers any decrease
in safety that may result from granting the exemption to be very small.
This was confirmed by the risk studies discussed in Section 3 of the
safety evaluation on this exemption request.
Accordingly, the Commission has determined, pursuant to 10 CFR
50.12(a), that this exemption is authorized by law and will not present
an undue risk to the public health and safety, and is consistent with
the common defense and security. In addition, the Commission has found
special circumstances in that granting of this exemption will result in
a benefit to public health and safety that compensates for any decrease
in safety that may result from the grant of the exemption. Therefore,
the Commission hereby grants the exemption from 10 CFR Part 50,
Appendix J, Sections III.D.1(a), III.D.2(a) and III.D.3 and Section
III.D.(b)(i) and III.D.2(b)(iii). The specific exemptions are stated as
in Sections IV, V, and VI above.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will have no significant impact on the
quality of the human environment (60 FR 19791). The exemption is
effective upon issuance.
Dated at Rockville, Maryland, this 26th day of April 1995.
For the Nuclear Regulatory Commission.
Elinor G. Adensam
Acting Director, Division of Reactor Projects-III/IV, Office of Nuclear
Reactor Regulation.
[FR Doc. 95-10887 Filed 5-2-95; 8:45 am]
BILLING CODE 7590-01-M
