[Federal Register Volume 63, Number 189 (Wednesday, September 30, 1998)]
[Proposed Rules]
[Pages 52201-52206]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-26204]
[[Page 52201]]
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NUCLEAR REGULATORY COMMISSION
10 CFR Part 50
RIN 3150-AF95
Monitoring the Effectiveness of Maintenance at Nuclear Power
Plants
AGENCY: Nuclear Regulatory Commission.
ACTION: Proposed rule.
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SUMMARY: The Nuclear Regulatory Commission (NRC) is proposing to amend
its power reactor safety regulations to require that licensees assess
the cumulative effect of out-of-service equipment on the plant's
capability to perform safety functions before beginning any maintenance
activity on structures, systems, or components within the scope of the
maintenance rule. The amendments would also clarify that the proposed
rule applies under all conditions of operation including normal
shutdown, that the safety assessments include both the plant conditions
before and those expected during planned maintenance activities, and
that the safety assessments are to be used to ensure that the plant is
not placed in a condition of significant risk or a condition that would
degrade the performance of safety functions to an unacceptable level.
DATES: Submit comments by December 14, 1998. Comments received after
this date will be considered if it is practical to do so, but the
Commission is able to ensure consideration only for comments received
on or before this date.
ADDRESSES: Mail comments to: The Secretary of the Commission, U.S.
Nuclear Regulatory Commission, Washington, DC 20555-0001. Attention:
Rulemakings and Adjudications Staff.
Deliver comments to: 11555 Rockville Pike, Rockville, Maryland,
between 7:30 a.m. and 4:15 p.m. on Federal workdays.
You may also provide comments via the NRC's interactive rulemaking
web site through the NRC home page (http://www.nrc.gov). From the NRC
home page, select ``Rulemaking'' from the tool bar. The interactive
rulemaking website may then be accessed by selecting ``Rulemaking
Forum.'' This site possesses the ability of uploading comments as files
(any format) if your web browser supports that function. For
information about the interactive rulemaking site, contact Ms. Carol
Gallagher, 301-415-5905, e-mail [email protected]
Certain documents related to this rulemaking, including comments
received, may be examined at the NRC Public Document Room, 2120 L
Street NW. (Lower Level), Washington, DC. These same documents also may
be viewed and downloaded electronically via the interactive rulemaking
website established by NRC for this rulemaking.
FOR FURTHER INFORMATION CONTACT: Richard P. Correia, Office of Nuclear
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC
20555, 301-415-1009, e-mail rpc@nrc.gov.
SUPPLEMENTARY INFORMATION:
Background
The NRC's Maintenance Team Inspections of all nuclear power plant
licensees in the late 1980s found the lack of consideration of plant
risk in prioritizing, planning, and scheduling maintenance activities
to be a common weakness. To address that weakness, paragraph (a)(3) of
10 CFR 50.65, the maintenance rule, currently includes the provision
that ``(I)n performing monitoring and preventive maintenance
activities, an assessment of the total plant equipment that is out of
service should be taken into account to determine the overall effect on
performance of safety functions.'' The maintenance rule was issued on
July 10, 1991.
During plant visits in mid-1994, several NRC senior managers
expressed concerns that licensees were increasing both the amount and
frequency of maintenance performed during power operation without
adequately evaluating safety when planning and scheduling these
maintenance activities. The NRC Executive Director for Operations (EDO)
addressed these concerns regarding the safety implications with
performing maintenance while at power to the president of the Institute
of Nuclear Power Operations (INPO) in a letter dated October 6, 1994.
In this letter, the EDO noted that it appeared that some licensees were
either not following INPO guidelines for the conduct of maintenance and
management of outages or had adopted only portions of the guidance. The
EDO also recommended that INPO support NEI and appropriate utility
managers during meetings with NRC senior managers to discuss the
concerns they raised during the site visits.
The growing amount of on-line maintenance (i.e., maintenance
performed during power operations) being performed by licensees and the
inadequate pre-maintenance safety evaluations have raised the
Commission's concern.
Discussion
The nuclear power industry has changed since the 1991 issuance of
the maintenance rule. Rate deregulation of the electric utility
industry will likely cause all nuclear power plants to seek ways to
operate more efficiently. One mechanism for increasing efficiency is
shortening refueling and maintenance outages. Licensees have come to
realize that performing more maintenance at power can lead to shorter
refueling outages and the reduction or elimination of mid-cycle
maintenance outages.
Licensees have relied upon their individual plant technical
specifications to help assure safe operation of the plant when
equipment is out of service. However, the removal of multiple pieces of
equipment, especially safety-related equipment, from service can
undermine the fundamental premise of the technical specifications for a
plant, which is to provide adequate protection against random failures.
During plant visits in mid-1994, several NRC senior managers had
concerns with the fact that licensees were increasing both the amount
and frequency of maintenance performed during power operations. Some
licensees were limiting the planned maintenance to a single train of a
system while others would allow multiple equipment in other systems
within a single train to be out of service as long as it did not
violate the plant's technical specifications. However, allowable outage
times specified in technical specifications are based upon a random
single failure in a system and a judgement of a reasonable time to
effect repairs before plant shutdown is required. Technical
specifications were not intended to address allowable outage times for
multiple equipment being out of service at the same time. Further, it
can not be implied that it is acceptable to voluntarily remove
equipment from service to perform on-line maintenance on the assumption
that such actions are bounded by a worst case single failure which is a
plant specific design requirement that is contained in a number of the
general design criteria (GDC) in 10 CFR 50, Appendix A. The NRC senior
managers also had concerns with the fact that on-shift personnel,
planning and scheduling personnel, and licensee management lacked an
understanding of the relative safety importance of safety systems or
combinations of equipment that would have risk significance if taken
out of service. It appeared that risk insights from plant specific
Individual Plant Examination (IPE)
[[Page 52202]]
results, whose purpose was to improve licensee understanding of the
plant's safety and to address potential vulnerabilities, were not fully
utilized in the plant's operational and maintenance decision process.
These concerns were addressed in a letter dated October 6, 1994, from
the Director of the Office of Nuclear Reactor Regulation to the
Executive Vice-President of the Nuclear Energy Institute. The growing
amount of maintenance performed during power operations and the
underutilization of risk insights in plant operations and maintenance
activities have raised the Commission's concern.
In determining the need for the maintenance rule a decade ago, one
factor the Commission considered was its belief that there existed ``a
need to broaden its capability to take timely enforcement action where
maintenance activities fail to provide reasonable assurance that
safety-significant SSCs [structures, systems, and components] are
capable of performing their intended function.'' Now, the Commission
desires to act to help ensure that there is reasonable assurance such
that maintenance activities will not place a plant in (1) a
configuration that would degrade unacceptably a SSC's capability to
perform its intended safety functions or (2) a risk-significant
configuration, i.e., a configuration for which the incremental
contribution to the annual risk associated with accidents that result
in damage to the reactor fuel or the release of fission products to the
environment is not insignificant.
The first 50 NRC maintenance rule baseline inspections (MRBIs) for
which inspection reports had been issued as of April 20, 1998, found
that all licensees had developed programs to implement the safety
assessment provision of paragraph (a)(3). However, at 5 sites,
instances were found in which the licensee did not assess the impact on
safety of total plant equipment out of service before it entered one or
more specific plant configurations for maintenance purposes. At 19
other sites, weaknesses--the term reserved for situations in which the
overall assessment of a licensee program has found the program, or
significant aspects of that program, to be particularly ineffective or
for individual findings that have either high safety significance or
programmatic implications--were found, among which were paragraph
(a)(3) safety assessment tools that did not include all high-safety-
significant SSCs.
Although the safety significance of the unassessed plant
configurations at the 5 sites was not quantitatively determined during
the inspection in all cases, it appears that some of the unassessed
configurations had resulted in plants that were in a state of
substantially greater risk than was realized by the licensees. Given
the concerns raised by NRC senior managers during site visits in 1994,
the increased amount of on-line maintenance, the number of missed
assessments and their apparent risk significance, in addition to the
weaknesses found with the paragraph (a)(3) safety assessment programs,
the Commission considers this to be a safety concern. The Commission,
therefore, believes it is necessary to explicitly require licensees to
perform safety assessments prior to removing equipment from service for
maintenance during all conditions of plant operations including normal
shutdown.
With regard to the operating conditions under which the proposed
rule would apply, extensive interaction among the NRC, the industry,
and the public has taken place over the need for regulations governing
activities during shutdown conditions (i.e., shutdown as may be defined
in each plant's individual technical specifications, but generally
considered as a time when all control rods are inserted and the average
reactor coolant temperature is below 200 deg.F). The question of
whether 10 CFR 50.65 applies during shutdown conditions became an
issue. The Commission desires to clarify that the rule does apply
during shutdown conditions.
Regarding which activities would be preceded by a safety
assessment, the Commission has recognized that, although definitions
regarding maintenance activities are fairly consistent from
organization to organization, there is some variation in the definition
of corrective maintenance. For example, some definitions bring a time
dependency while some others consider the urgency of the repair. To
eliminate inconsistency, and to cause more prudent use of the safety
assessments, the Commission desires the regulation to cover all planned
maintenance activities, rather than only the recommended monitoring and
preventive maintenance in the current rule. Each planned non-emergency
maintenance activity would now include a safety assessment prior to its
being authorized to begin. In fact, many licensees have followed the
guidance contained in Regulatory Guide 1.160 and NUMARC 93-01 and have
already voluntarily included all planned maintenance activities in the
scope of their safety assessment programs.
With regard to the safety assessments themselves, licensee
implementation has been inconsistent. The Commission desires to specify
that an appropriate safety assessment would include a review the
current condition of the plant and the plant condition expected during
the planned maintenance activity. Assessing the current plant
configuration as well as expected changes to plant configuration that
will result from the proposed maintenance activities, as would be
called for under paragraph (a)(4) of the proposed rule, is intended to
ensure that the plant is not placed in risk-significant configurations,
i.e., a configuration for which the incremental contribution to the
annual risk is not insignificant, or a configuration that would degrade
safety functions to an unacceptable level. These assessments do not
necessarily require that a quantitative assessment of probabilistic
risk be performed. The licensee would have the flexibility to perform a
probabilistic and/or deterministic assessment, as appropriate. The
level of sophistication with which such assessments are performed is
expected to vary, based on the circumstances involved. It should be
understood, however, that the contribution to risk of a specific plant
configuration depends on both the degree of degradation of the safety
functions and the duration for which the plant is in that
configuration. Further, assessing the degree of safety function
degradation requires that there be an understanding of the impact of
removal of the equipment on the capability of the plant to prevent or
mitigate accidents and transients. The assessments may range from
deterministic judgements to the use of an on-line, living probabilistic
risk assessment (PRA).
Additional guidance will be developed and promulgated in Regulatory
Guide 1.160, Revision 3 (proposed), to assist licensees in implementing
this provision of the proposed rule. The guidance will contain
information regarding risk-significant configurations and unacceptable
levels of safety function degradation.
Proposed Rule
This proposed rule would make five changes to 10 CFR 50.65:
1. Add an introductory paragraph to 10 CFR 50.65 clarifying that
the proposed rule applies under all conditions of operation, including
normal shutdown.
Prior to paragraph (a)(1), add the following wording: ``The
requirements of this section are applicable during all
[[Page 52203]]
conditions of plant operation, including normal shutdown operations.''
The intent of this paragraph is to ensure that safety assessments are
performed before maintenance activities when the plants are shut down
as well as when the plants are at power. The shutdown condition may be
defined in a plant's technical specifications, but the intent of this
paragraph is that shutdown is generally considered as a time when all
control rods are inserted and the average reactor coolant temperature
is below 200 deg. F.
2. Delete the last sentence of paragraph (a)(3) and create a new
paragraph, (a)(4), that requires the performance of safety assessments.
The proposed rule would remove the last sentence of paragraph
(a)(3) and would add a new paragraph, (a)(4), as follows in its
entirety: ``Before performing maintenance activities on structures,
systems, or components within the scope of this section (including, but
not limited to, surveillance testing, post-maintenance testing,
corrective maintenance, performance/condition monitoring, and
preventive maintenance), an assessment of the current plant
configuration as well as expected changes to plant configuration that
will result from the proposed maintenance activities shall be conducted
to determine the overall effect on performance of safety functions. The
results of this assessment shall be used to ensure that the plant is
not placed in risk-significant configurations or configurations that
would degrade the performance of safety functions to an unacceptable
level.'' Deleting the current last sentence in paragraph (a)(3) will
remove the recommendation for performing safety assessments from the
paragraph that contains the periodic, programmatic, long-term review
considerations of the rule. Creating a new paragraph, (a)(4),
specifically for the safety assessment requirements would cause the
assessment concept to stand as a separate entity within the maintenance
rule.
3. Define in paragraph (a)(4) the scope of the requirement for
performing those assessments to be all conditions of operation
including normal shutdown.
The proposed rule would add the following in paragraph (a)(4) to
define the scope of pre-maintenance safety assessments: ``Before
performing maintenance activities on structures, systems, or components
within the scope of this section (including, but not limited to,
surveillance testing, post-maintenance testing, corrective maintenance,
performance/condition monitoring, and preventive maintenance), an
assessment * * * shall be conducted * * * .'' The NRC's intent is that
licensees perform safety assessments before all planned maintenance
activities that require removing from service equipment that is within
the scope of the maintenance rule, as defined in 10 CFR 50.65(b) and
(a)(1). The safety assessments required in this paragraph need not be
sophisticated probabilistic risk assessment analyses in all cases.
Licensees would have the flexibility to use probabilistic and/or
deterministic methods, as appropriate, when performing the safety
assessments required by paragraph (a)(4).
4. Specify in paragraph (a)(4) that the safety assessments are to
examine the extant plant condition and the condition expected during
the planned maintenance activity.
The proposed rule would include the following wording in paragraph
(a)(4): ``* * * an assessment of the current plant configuration as
well as expected changes to the plant configuration that will result
from the proposed maintenance activities * * * .'' The NRC's intent is
that a reasonable safety assessment be performed. The assessment may
range from simple and straightforward to complex. However,
notwithstanding the degree of sophistication required for the
assessment, the NRC intends that the assessment will examine the plant
condition existing prior to the commencement of the maintenance
activity and examine the changes expected by the proposed maintenance
activity.
5. Specify in paragraph (a)(4) that the objective of performing the
safety assessments is to ensure that the plant is not placed in risk-
significant configurations or configurations that would degrade the
performance of safety functions to an unacceptable level.
The proposed rule would add in paragraph (a)(4) the wording to
specify the NRC's expectations regarding the use of each safety
assessment, as follows: ``The results of this assessment shall be used
to ensure that the plant is not placed in risk-significant
configurations or configurations that would degrade the performance of
safety functions to an unacceptable level.'' The NRC's intent is to
require that each licensee perform a safety assessment before
undertaking each planned maintenance activity and be aware of the risk
issues associated with that maintenance activity. The guidance to be
developed for licensees and promulgated in Regulatory Guide 1.160,
Revision 3 (proposed), is expected to assist the industry in
implementing this provision of the proposed rule, providing guidance
regarding risk-significant configurations and unacceptable levels of
safety function degradation.
The Commission requests public comment on these proposed rule
provisions. The Commission also requests public comment on the
explanatory language in item 3 pertaining to licensee flexibility to
use probabilistic and/or deterministic methods to perform the safety
assessments. Specifically, should there be further clarification of
this point in the final rule?
Finding of No Significant Environmental Impact: Environmental
Assessment
The Commission has determined under the National Environmental
Policy Act of 1969, as amended, and the Commission's regulations in
Subpart A of 10 CFR Part 51 that this rule, if adopted, would not be a
major Federal action significantly affecting the quality of the human
environment and, therefore, an environmental impact statement is not
required. The draft environmental assessment that forms the basis for
this determination reads as follows.
Identification of the Proposed Action
The Commission is proposing to amend its regulations to require
commercial nuclear power plant licensees to perform assessments of the
plant's status before performing maintenance activities on structures,
systems, and components (SSCs) within the scope of 10 CFR 50.65, the
maintenance rule. The rule would be modified by adding an introductory
sentence to clarify that the proposed rule would apply under all
conditions of operation, including normal shutdown; deleting the last
sentence of paragraph (a)(3); and creating a new paragraph, (a)(4). The
new paragraph (a)(4) would change ``should'' to ``shall'' regarding the
performance of safety assessments; define the scope of the requirement
for performing those assessments to include all planned maintenance
activities; specify that the safety assessments are to examine the
extant plant condition and the condition expected during the
maintenance activity; and specify that the safety assessments are to be
used to ensure that, by the conduct of maintenance, the plant is not
placed in risk-significant conditions or safety system performance is
not degraded to an unacceptable level.
[[Page 52204]]
The Need for the Proposed Action
Paragraph (a)(3) of the maintenance rule, in part, currently
recommends that, ``(I)n performing monitoring and preventive
maintenance activities, an assessment of the total plant equipment that
is out of service should be taken into account to determine the overall
effect on performance of safety functions.'' The Commission believes
the performance of this type of assessment is prudent. The maintenance
rule baseline inspections, being performed at each commercial nuclear
power plant site, have found that all inspected licensees have
implemented programs to perform the assessments, but about half of the
sites inspected had programs with discernable weaknesses in this area,
including instances in which, in accordance with the licensee's own
programs, safety assessments should have been made but were not.
Because of the hortatory nature of the safety assessment provision in
Sec. 50.65(a)(3), the Commission cannot ensure that licensees perform
the assessments. Moreover, licensees are free to remove the performance
of the assessments from their programs as they so desire. This proposed
change to the Commission's regulations will permit the Commission to
ensure that licensees perform the assessments, as appropriate.
The other changes are clarifications regarding applicability of the
rule. During preliminary discussions prior to potential development of
a rule on shutdown plant operations, a major question arose regarding
whether 10 CFR 50.65 requirements apply during the time a plant is shut
down. The Commission concluded that inclusion of a statement to the
affirmative would eliminate the doubt.
Removing the provision regarding safety assessments from paragraph
(a)(3) and creating for it a new, separate paragraph, (a)(4), would
disassociate that new requirement from the more time-dependent
requirement for evaluating of the program and the program's
effectiveness at maintaining an appropriate balance between reliability
and availability for each SSC. In the new paragraph, the requirement
for safety assessment performance is stipulated to ensure licensees
will perform those assessments. Because there were questions regarding
when the assessments were to be performed, what plant conditions are to
be evaluated and how they were to be used, the proposed new paragraph
(a)(4) describes that the assessments are to be performed before all
planned maintenance activities, are to examine pre-maintenance plant
conditions and expected changes due to the proposed maintenance
activity, and are to be used to ensure that the plant is not placed in
risk-significant configurations or configurations that would degrade
the performance of safety functions to an unacceptable level.
Environmental Impacts of the Proposed Action
The proposed rule would require that commercial nuclear power plant
licensees perform certain assessments of plant equipment status prior
to performing all planned maintenance activities. The purpose of the
proposed rule is to increase the effectiveness of the maintenance rule
by requiring licensees to perform an assessment of plant conditions
prior to planned maintenance and changes expected to result from the
planned maintenance activity, to ensure that licensees understand the
assessments are to be performed when the plant is shut down as well as
at power, and to improve licensees' understanding of what conditions to
assess and to what use to put the completed assessment. Accordingly,
implementation of this proposed rule would not have any significant
adverse impact on the quality of the human environment. The Commission
believes that proper implementation of the proposed rule will reduce
the likelihood of an accidental release of radioactive material caused
by imprudently prioritized, planned, or scheduled maintenance.
The determination of this environmental assessment is that there
will be no significant offsite impact to the public from this action.
The NRC has also committed to complying with Executive Order (EO)
12898, ``Federal Actions to Address Environmental Justice in Minority
Populations and Low-Income Populations,'' dated February 11, 1994, in
all its actions. The NRC has determined that there are no
disproportionate, high, or adverse impacts on minority or low-income
populations. In the letter and spirit of EO 12898, the NRC is
requesting public comment on any environmental justice considerations
or questions that the public thinks may be related to this proposed
rule but somehow were not addressed. Comments on any aspect of the
Environmental Assessment, including environmental justice, may be
submitted to the NRC as indicated under the ADDRESSES heading.
States Consulted and Sources Used
The NRC has sent a copy of this proposed rule to every State
Liaison Officer and requested his or her comments on the Environmental
Assessment.
Paperwork Reduction Act Statement
This proposed rule does not contain a new or an amended information
collection requirement subject to the requirements of the Paperwork
Reduction Act of 1995 (44 U.S.C. 3501 et seq.). Existing requirements
were approved by the Office of Management and Budget, approval number
3150-0011.
Public Protection Notification
If an information collection requirement does not display a
currently valid OMB control number, the NRC may not conduct or sponsor,
and a person is not required to respond to, the information collection.
Regulatory Analysis
The Commission has prepared a draft regulatory analysis on this
proposed regulation. The analysis examined the costs and benefits of
the alternatives considered by the Commission for revising 10 CFR
50.65, the maintenance rule. Those alternatives were to (1) make no
change to the rule, (2) require the safety assessments currently
recommended in paragraph (a)(3) of the rule, and (3) make comprehensive
revisions to paragraph (a)(3) of the rule. The analysis selected
Alternative 2 as the preferred course of action. Details of the
alternative selection are contained in the draft analysis, which is
available for inspection in the NRC Public Document Room, 2120 L Street
NW (Lower Level), Washington, D.C. Single copies of the analysis may be
obtained from Richard P. Correia, Office of Nuclear Reactor Regulation,
U.S. Nuclear Regulatory Commission, Washington, DC 20555, 301-415-1009,
e-mail rpc@nrc.gov.
The Commission requests public comments on the draft regulatory
analysis. Comments on the draft analysis may be submitted to the NRC as
indicated under the ADDRESSES heading.
Regulatory Flexibility Certification
In accordance with the Regulatory Flexibility Act of 1980 (5 U.S.C.
605(b)), the Commission certifies that this proposed rule will not, if
adopted, have a significant economic impact on a substantial number of
small entities. This proposed rule affects only the operation of
nuclear power plants. The companies that own these plants do not fall
within the scope of the definition of small entities set forth in the
Regulatory Flexibility Act or the size standards adopted by the NRC (10
CFR 2.810).
[[Page 52205]]
Backfit Analysis
As required by 10 CFR 50.109, the Commission has completed a
backfit analysis for this proposed rule. The Commission has determined,
on the basis of this analysis, that backfitting to comply with the
requirements of this proposed rule provides a substantial increase in
protection to the public health and safety or the common defense and
security at a cost that is justified by the increased protection.
When the maintenance rule was first promulgated in 1991, the NRC
staff did not foresee the significant changes licensees would be making
in maintenance practices. To enhance operational efficiency brought
about by the rate deregulation of the electric utility industry,
licensees are shortening their refueling outages by performing more
maintenance while the plant is at power. At-power maintenance practices
have evolved to the point that not only are major systems and
components taken off line, but also multiple systems and components are
taken off line simultaneously. Taking systems and components off line
for maintenance could result in an increased likelihood of an accident
or transient, compared to risk that occurs from expected random
equipment failures.
The objective of this proposed rule is to make mandatory that
licensees assess the cumulative impact of out-of-service equipment on
the capability of the plant to perform safety functions and that
licensees consider the results of the assessment before undertaking
maintenance activities at operating nuclear power plants in order to
ensure that the plants are not placed in risk-significant
configurations or configurations that would degrade the performance of
safety functions to an unacceptable level. Thus, the proposed rule
would state that licensees must perform safety assessments before
removing SSCs from service for planned maintenance.
In addition, this proposed rule would (1) add an introductory
sentence to 10 CFR 50.65 clarifying that the rule applies under all
conditions of operation, including normal shutdown; (2) delete the last
sentence of paragraph (a)(3) of the rule and create a new paragraph,
(a)(4), that requires the performance of safety assessments; (3)
specify that the scope of the requirement for performing those
assessments covers all planned maintenance activities; (4) specify that
the safety assessments are to examine the extant plant condition and
the condition expected during the maintenance activity; and (5) specify
that the results of the safety assessments are to be used to help the
licensee ensure that the plant is not placed in risk-significant
configurations or configurations that would degrade safety functions to
an unacceptable level.
The pre-maintenance assessments, along with the clarifications
regarding their scope and their use, which the Commission proposes to
require are intended to cause licensees to manage this risk and ensure
their plants are not placed in risk-significant conditions or
conditions in which the performance of safety functions is not degraded
to unacceptable levels.
The details of this backfit analysis have been incorporated in the
regulatory analysis.
For the reasons elaborated in the regulatory analysis, which also
contains cost information, the Commission concludes that the proposed
modification to the maintenance rule will result in a level of safety
beyond that currently provided by the Commission's regulations, a
substantial increase in the overall protection of public health and
safety, and that the net costs of the rule are justified in view of
this increased level of safety.
List of Subjects in 10 CFR Part 50
Antitrust, Classified information, Criminal penalties, Fire
protection, Intergovernmental relations, Nuclear power plant and
reactors, Radiation protection, Reactor siting criteria, Reporting and
recordkeeping requirements.
For the reasons set out in the preamble and under the authority of
the Atomic Energy Act of 1954, as amended; the Energy Reorganization
Act of 1974, as amended; and 5 U.S.C. 553, the NRC is proposing to
adopt the following amendments to 10 CFR Part 50:
PART 50--DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION
FACILITIES
1. The authority citation for part 50 continues to read as follows:
Authority: Secs. 102, 103, 104, 105, 161, 182, 183, 186, 189, 68
Stat. 936, 937, 938, 948, 953, 954, 955, 956, as amended, sec. 234,
83 Stat. 444, as amended (42 U.S.C. 2132, 2133, 2134, 2135, 2201,
2232, 2233, 2236, 2239, 2282); secs. 201, as amended, 202, 206, 88
Stat. 1242, as amended, 1244, 1246, (42 U.S.C. 5841, 5842, 5846).
Section 50.7 also issued under Pub. L. 95-601, sec. 10, 92 Stat.
2951 (42 U.S.C. 5851). Section 50.10 also issued under secs. 101,
185, 68 Stat. 936, 955, as amended (42 U.S.C. 2131, 2235); sec. 102,
Pub. L. 91-190, 83 Stat. 853 (42 U.S.C. 4332). Sections 50.13,
50.54(dd), and 50.103 also issued under sec. 108, 68 Stat. 939, as
amended (42 U.S.C. 2138). Sections 50.23, 50.35, 50.55, and 50.56
also issued under sec. 185, 68 Stat. 955 (42 U.S.C. 2235). Sections
50.33a, 50.55a, and Appendix Q also issued under sec. 102, Pub. L.
91-190, 83 Stat. 853 (42 U.S.C. 4332). Sections 50.34 and 50.54 also
issued under sec. 204, 88 Stat. 1245 (42 U.S.C. 5844). Sections
50.58, 50.91, and 50.92 also issued under Pub. L. 97-415, 96 Stat.
2073 (42 U.S.C. 2239). Section 50.78 also issued under sec. 122, 68
Stat. 939 (42 U.S.C. 2152). Sections 50.80-50.81 also issued under
sec. 184, 68 Stat. 954, as amended (42 U.S.C. 2234). Appendix F also
issued under sec. 187, 66 Stat. 955 (42 U.S.C. 2237).
2. In Sec. 50.65, an introductory paragraph is added, paragraph
(a)(3) is revised, and a new paragraph (a)(4) is added, to read as
follows:
Sec. 50.65 Requirements for monitoring the effectiveness of
maintenance at nuclear power plants.
The requirements of this section are applicable during all
conditions of plant operation, including normal shutdown operations.
(a) * * *
(3) Performance and condition monitoring activities and associated
goals and preventive maintenance activities shall be evaluated at least
every refueling cycle provided the interval between evaluations does
not exceed 24 months. The evaluations shall be conducted taking into
account, where practical, industry-wide operating experience.
Adjustments shall be made where necessary to ensure that the objective
of preventing failures of structures, systems, and components through
maintenance is appropriately balanced against the objective of
minimizing unavailability of structures, systems, and components due to
monitoring or preventive maintenance.
(4) Before performing maintenance activities on structures,
systems, or components within the scope of this section (including, but
not limited to, surveillance testing, post-maintenance testing,
corrective maintenance, performance/condition monitoring, and
preventive maintenance), an assessment of the current plant
configuration as well as expected changes to plant configuration that
will result from the proposed maintenance activities shall be conducted
to determine the overall effect on performance of safety functions. The
results of this assessment shall be used to ensure that the plant is
not placed in risk-significant configurations or configurations that
would degrade the performance of safety functions to an unacceptable
level.
* * * * *
Dated at Rockville, Maryland, this 24th day of September, 1998.
[[Page 52206]]
For the Nuclear Regulatory Commission.
John C. Hoyle,
Secretary of the Commission.
[FR Doc. 98-26204 Filed 9-29-98; 8:45 am]
BILLING CODE 7590-01-P
