Monitoring the Effectiveness of Maintenance at Nuclear Power Plants

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

ry 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 [email protected].

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

ess 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

commended 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

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)

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

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

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

gnificance, 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

e 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

eterministic 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

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

ety 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

c, 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

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

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

ed, 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.

The Need for the Proposed Action

ify 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.

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

priate.

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

med 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

nt 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

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 [email protected].

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

ysis 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 [email protected].

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).

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

tional 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,

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

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)

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.