[Federal Register Volume 60, Number 136 (Monday, July 17, 1995)]
[Notices]
[Pages 36447-36448]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-17446]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-278]
Exemption; Notice
In the matter of PECO Energy Company, Public Service Electric
and Gas Company, Delmarva Power and Light Company, Atlantic City
Electric Company (Peach Bottom Atomic Power Station, Unit 3)
I
PECO Energy Company, et al. (PECo, the licensee), is the holder of
Facility Operating License No. DPR-56, which authorizes operation of
the Peach Bottom Atomic Power Station (PBAPS), Unit 3. 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 PBAPS, Unit 3, facility consists of a boiling water reactor
located in York County, Pennsylvania.
II
Section 50.54(o) of 10 CFR Part 50 requires that primary reactor
containments for water cooled power reactors by subject to the
requirements of Appendix J to 10 CFR Part 50. Appendix J contains the
leakage test requirements, schedules, and acceptance criteria for tests
of the leak tight integrity of the primary reactor containment and
systems and components which penetrate the containment. Section III.D.1
of Appendix J to 10 CFR Part 50 requires that a set of three Type A
tests shall be performed, at approximately equal intervals during each
10-year service period. The third test of each set shall be conducted
when the plant is shut down for the 10-year plant inservice inspections
(ISI). 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.
III
In its letter dated November 21, 1994, 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 Leak Rate Tests (CILRTs)) be
performed, at approximately equal intervals, during each 10-year
service period. The exemption applies to the second 10-year service
period; subsequent service periods are not changed.
The request for a one-time exemption would allow an extension of
the second 10-year Type A test service period and would allow the
performance of the three Type A tests in the second 10-year service
period at intervals that are not approximately equal. It does not
affect the third 10-year service period.
In its submittal, the licensee provided a table of historical leak
test results for PBAPS Unit 3. Within the second 10-year service
period, satisfactory Type A tests were performed in January 1986 and
November 1989. In addition, an additional satisfactory Type A test was
performed in December 1991 following certain plant modifications.
Current Technical Specifications (TS) and 10 CFR Part 50, Appendix
J, would require the licensee to perform a Type A test during Unit 3
refueling outage 10 (3R010) scheduled for September 1995 in order to
comply with the requirements to perform three Type A tests within the
current service period at approximately equal intervals.
Furthermore, 10 CFR Part 50, Appendix J, also requires the licensee
to perform a type A test during the next refueling outage (Unit 3
refueling outage 11 (3R011) scheduled for September 1997) in order to
comply with the requirement of 10 CFR Part 50, Appendix J, Section
III.D.1, that the third test be performed when the plant is shut down
for the 10-year inservice inspections. The current 10-year ISI period
ends in November 1997 and ISI inspections are scheduled for September
1997. Therefore, to fully comply with Appendix J, the licensee would
have to perform CILRTs during the tenth and eleventh refueling outages
for Unit 3.
The licensee proposed to perform the next Unit 3 Type A test during
Unit 3 refueling outage 11 scheduled to start in September 1997. The
effect of this proposal would be to extend the current Appendix J 10-
year service period that would result in the interval between
successive Type A tests being extended to approximately 70 months.
Strict compliance with Section III.D.1 would require the interval
between successive Type A tests to be approximately 40 months.
The licensee performed a review of the history of the PBAPS Unit 3
Type A test results to evaluate the risk of activity-based and time-
based degradation. This review identified three activity-based
component failures detected during past Type A tests. The measured mass
point and total time leakage rates measured for the April 1977 CILRT
stabilized at approximately 1.1% wt/day, which failed to meet the
[[Page 36448]]
TS and 10 CFR Part 50, Appendix J criterion of less than 0.375% wt/day
(0.75 La). Following the completion of repairs of a leaking torus water
level instrument, the CILRT was repeated with an as-left leakage of
0.322% wt/day. After this failure, the licensee modified the plant
procedures so that a similar failure, in the future, would be detected
by a local leak rate test (LLRT). The measured mass point and total
time leakage rates measured for the September 1981 CILRT stabilized at
approximately .389% wt/day, which failed to meet the TS and 10 CFR Part
50, Appendix J criterion of less than 0.375% wt/day (0.75 La).
Following the completion of repairs to a missing instrument O-ring, the
CILRT was repeated with an as-left leakage of 0.185% wt/day. After this
failure, the licensee modified the plant procedures so that a similar
failure, in the future, would be detected by a leak rate test following
relevant instrument maintenance. The measured mass point and total time
leakage rates measured for the August 1983 CILRT stabilized at
approximately .784% wt/day, which failed to meet the TS and 10 CFR Part
50, Appendix J criterion of less than 0.375% wt/day (0.75 La).
Following the completion of repairs to a valve packing leak, the CILRT
was repealed with an as-left leakage of 0.058% wt/day. After this
failure, the licensee modified the plant procedures so that similar
valve packing is local leak rate tested and measured.
These failures were identified as activity based failures for which
the licensee implemented corrective action. The licensee did not
identify any time based failures.
The type B and C test (i.e., LLRT) program 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, since the last Type A test, that could adversely affect the
test results.
Current TS 4.7.A.2.h requires that the interior surfaces of the
drywell and torus shall be visually inspected each operating cycle for
evidence of deterioration. In addition, TS 4.7.A.2.h requires that the
external surfaces of the torus below the water level be inspected on a
routine basis for evidence of torus corrosion or leakage. TS 4.7.4
requires that a visual inspection of the suppression chamber interior
be conducted at each major refueling outage. These inspections provide
similar information as would be obtained to meet the requirement of
Section V.A of 10 CFR Part 50, Appendix J. The licensee is required to
perform these TS surveillances in the upcoming refueling outage 3R010.
The licensee further notes that the performance of consecutive Type
A tests in refueling outages 3R010 and 3R011, to meet the requirements
of the TS and Appendix J, would result in additional radiation exposure
to personnel. Performing the Type A test during two consecutive
refueling outages in order to comply with the TS and 10 CFR Part 50,
Appendix J, would result in an unnecessary increase in personnel
radiation exposure and an increase in cost by extending the length of
one of the affected refueling outages. 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 an additional test for a 24-month difference in
interval are not offset by the benefits of the additional test.
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 and
safety, and are consistent with the common defense and security; and
(2) when special circumstances are present. Special circumstances are
present whenever, according to 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 * * *.''
The licensee provided information regarding the requirements of 10
CFR 50.12(a)(2)(ii). The licensee stated that the underlying purpose of
10 CFR Part 50, Appendix J, Section III.D.1(a), is to establish and
maintain a level of confidence that any primary containment leakage,
during a hypothetical design basis accident, will remain less than or
equal to the maximum allowable value, La, established by Appendix J
through the performance of periodic Type A testing. The licensee stated
that, for the technical justification discussed above, performance of
Type A tests during the next two Unit 3 refueling outages was not
necessary to meet the underlying purpose of the rule.
The NRC staff has reviewed the licensee's proposed exemption,
including Type A test history, and concluded that the impact on safety
of this deviation from the scheduler requirements of Appendix J is not
significant. Accordingly, the staff finds that an additional test
(during the scheduled 1995 refueling outage) would not provide
substantially different information and that the intent of Appendix J
would be met. Therefore, the subject exemption request meets the
special circumstances of 10 CFR 50.12(a)(2)(ii), in that the additional
Type A test is not necessary to achieve the underlying purpose of the
rule.
The staff also finds, for the technical reasons discussed above,
that extending the service period and extending the interval between
Type A tests are acceptable.
V
Accordingly, the Commission has determined that, pursuant to 10 CFR
50.12(a)(1), this 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. The Commission further determined, as
discussed above, that there are special circumstances present, as
specified in 10 CFR 50.12(a)(2)(ii), such that application of 10 CFR
Part 50, Appendix J, Section III.D.1(a) is not necessary in order to
achieve the underlying purpose of this regulation. Therefore, the
Commission hereby grants a one-time scheduler exemption from the
requirements of 10 CFR Part 50, Appendix J, Section III.D.1.(a), to
extend the second 10-year Type A test service period for Peach Bottom
Atomic Power Station, Unit 3, such that the third periodic Type A test
may be performed during Unit 3 refueling outage 11, currently scheduled
for September 1997, and such that the three Type A tests in the second
10-year service period are performed at intervals that are not
approximately equal.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will have no significant effect on the
quality of the human environment (60 FR 35239).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 10th day of July 1995.
For the Nuclear Regulatory Commission.
Steven A. Varga,
Director, Division of Reactor Projects-I/II, Office of Nuclear Reactor
Regulation.
[FR Doc. 95-17446 Filed 7-14-95; 8:45 am]
BILLING CODE 7590-01-M
