# 60 FR 9634: Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors

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URL: https://www.frixlaw.com/law-library/statutes/FR_PRORULE_95-4167

## Section

- **Citation:** 60 FR 9634
- **Heading:** Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Federal Register / Vol. 60 / 60 FR 9634

## Text

NUCLEAR REGULATORY COMMISSION
10 CFR Part 50

RIN 3150-AF00

Primary Reactor Containment Leakage Testing for Water-Cooled
Power Reactors

AGENCY: Nuclear Regulatory Commission.

ACTION: Proposed rule.

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SUMMARY: The Nuclear Regulatory Commission is proposing to amend its
regulations to provide a performance-based option for leakage rate
testing of containments of light-water-cooled nuclear power plants.
This option will be available for voluntary adoption by licensees, in
lieu of compliance with the current prescriptive requirements contained
in the current regulation. This action is aimed at improving the focus
of the regulations by eliminating prescriptive requirements that are
marginal to safety. The proposed rule would allow test intervals to be
based on system and component performance, and provide licensees
greater flexibility for cost-effective implementation methods of
regulatory safety objectives.

DATES: Submit comments by May 8, 1995. Comments received after this
date will be considered if it is practical to do so, but the Commission
is able to assure consideration only for comments received on or before
this date.

ADDRESSES: Send comments to: Secretary, U.S. Nuclear Regulatory
Commission, Washington, DC 20555. ATTN: Docketing and Service Branch.
Hand deliver comments to: 11555 Rockville Pike, Rockville,
Maryland, between 7:45 a.m. and 4:15 p.m. Federal workdays.
Comments may be submitted electronically, in either ASCII text or
Wordperfect format (version 5.1 or later), by calling the NRC
Electronic Bulletin Board on FedWorld. The bulletin board may be
accessed using a personal computer, a modem, and one of the commonly
available communications software packages, or directly via Internet.
Background documents on the rulemaking are also available for
downloading and viewing on the bulletin board
either ASCII text or
Wordperfect format (version 5.1 or later), by calling the NRC
Electronic Bulletin Board on FedWorld. The bulletin board may be
accessed using a personal computer, a modem, and one of the commonly
available communications software packages, or directly via Internet.
Background documents on the rulemaking are also available for
downloading and viewing on the bulletin board.
If using a personal computer and modem, the NRC subsystem on
FedWorld can be accessed directly by dialing the toll free number: 1-
800-303-9672. Communication software parameters should be set as
follows: Parity to none, data bits to 8, and stop bits to 1 (N,8,1).
Using ANSI or VT-100 terminal emulation, the NRC rulemaking subsystems
can then be accessed by selecting the ``Rules Menu'' option from the
``NRC Main Menu.'' For further information about options available for
NRC at FedWorld consult the ``Help/Information Center'' from the ``NRC
Main Menu.'' Users will find the ``FedWorld Online User's Guides''
particularly helpful. Many NRC subsystems and databases also have a
``Help/Information Center'' option that is tailored to the particular
subsystem.
The NRC subsystem on FedWorld can also be accessed by a direct dial
phone number for the main FedWorld BBS: 703-321-8020; Telnet via
Internet: fedworld.gov (192.239.93.3); File Transfer Protocol (FTP) via
Internet: ftp.fedworld.gov (192.239.92.205); and World Wide Web using:
http:// www.fedworld.gov (this is the Uniform Resource
Locator (URL)).
If using a method other than the toll free number to contact
FedWorld, then the NRC subsystem will be accessed from the main
FedWorld menu by selecting the ``F--Regulatory, Government
Administration and State Systems,'' then selecting ``A--Regulatory
Information Mall''. At that point, a menu will be displayed that has an
option ``A--U.S. Nuclear Regulatory Commission'' that will take you to
the NRC Online main menu
than the toll free number to contact
FedWorld, then the NRC subsystem will be accessed from the main
FedWorld menu by selecting the ``F--Regulatory, Government
Administration and State Systems,'' then selecting ``A--Regulatory
Information Mall''. At that point, a menu will be displayed that has an
option ``A--U.S. Nuclear Regulatory Commission'' that will take you to
the NRC Online main menu. You can also go directly to the NRC Online
area by typing ``/go nrc'' at a FedWorld command line. If you access
NRC from FedWorld's main menu, then you may return to FedWorld by
selecting the ``Return to FedWorld'' option from the NRC Online Main
Menu. However, if you access NRC at FedWorld by using NRC's toll-free
number, then you will have full access to all NRC systems, but you will
not have access to the main FedWorld system. For more information on
NRC bulletin boards call Mr. Arthur Davis, Systems Integration and
Development Branch, U.S. Nuclear Regulatory Commission, Washington, DC
20555, telephone (301) 415-5780; e-mail AXD[email protected].
Examine comments received, the draft environmental assessment and
findings of no significant impact, and the draft regulatory analysis
at: The NRC Public Document Room, 2120 L Street NW. (Lower Level),
Washington, DC; the PDR's mailing address is Mail Stop LL-6,
Washington, DC 20555; phone (202) 634-3273; fax (202) 634-3343. Copies
of the documents may be obtained from the PDR for a fee. These
documents may also be viewed and downloaded electronically via the
Electronic Bulletin Board established by NRC for this rulemaking.
The NRC also requests public comment on Draft NUREG-1493,
``Performance-Based Containment Leak Test Program.'' A free single copy
of draft NUREG-1493 may be requested by written request to the U.S.
Nuclear Regulatory Commission, ATTN: Distribution Section, Room P1-37,
Washington, DC 20555; fax (301) 504-2260
tronically via the
Electronic Bulletin Board established by NRC for this rulemaking.
The NRC also requests public comment on Draft NUREG-1493,
``Performance-Based Containment Leak Test Program.'' A free single copy
of draft NUREG-1493 may be requested by written request to the U.S.
Nuclear Regulatory Commission, ATTN: Distribution Section, Room P1-37,
Washington, DC 20555; fax (301) 504-2260. Comments on draft NUREG-1493
may be submitted to: Chief, Rules Review and Directives Branch,
Division of Freedom of Information and Publication Services, Mail Stop
T-6D59, U.S. Nuclear Regulatory Commission, Washington, DC 20555. Hand
deliver comments on draft NUREG-1493 to 11545 Rockville Pike, Maryland
between 7:45 a.m. and 4:15 p.m. on Federal workdays. Comments on draft
NUREG-1493 may be submitted electronically as indicated above under the
ADDRESSES heading.

FOR FURTHER INFORMATION CONTACT: Dr. Moni Dey, Office of Nuclear
Regulatory Research, U.S. Nuclear Regulatory Commission, Washington, DC
20555, telephone (301) 415-6443, e-mail [email protected]

SUPPLEMENTARY INFORMATION:
Background

The NRC is proposing to amend 10 CFR part 50, appendix J in an
effort to relax and allow alternatives to those requirements that are
prescriptive and marginal to safety and yet impose a significant
regulatory burden on licensees. NRC reactor licensees are required
currently to conduct periodic primary reactor containment leakage
testing in accordance with 10 CFR part 50, appendix J, ``Primary
Reactor Containment Leakage Testing for Water-Cooled Power Reactors.''
Appendix J is currently prescriptive in that it specifies leak test
frequencies, pretest requirements, test methods, and reporting
requirements.

NRC's Marginal to Safety/Regulatory Improvement Program
y to conduct periodic primary reactor containment leakage
testing in accordance with 10 CFR part 50, appendix J, ``Primary
Reactor Containment Leakage Testing for Water-Cooled Power Reactors.''
Appendix J is currently prescriptive in that it specifies leak test
frequencies, pretest requirements, test methods, and reporting
requirements.

NRC's Marginal to Safety/Regulatory Improvement Program

In 1984, the NRC staff initiated a program to make regulatory
requirements more efficient by eliminating those with marginal impact
on safety. The NRC's initiative to eliminate requirements marginal to
safety recognizes both the dynamic nature of the regulatory process and
that the importance and safety contribution of some existing regulatory
requirements may not have been accurately predicted when adopted or may
have diminished with time. The availability of new technical
information and methods justify a review and modification of existing
requirements.
The NRC solicited comments from industry on specific regulatory
requirements and associated regulatory positions that needed
reevaluation. The Atomic Industrial Forum conducted a survey providing
most of industry's input, published for the NRC as NUREG/CR-43301,
``Review of Light Water Reactor Regulatory Requirements,'' Vol. 1,
April 1986. A list of 45 candidates for potential regulatory
modification were identified. The NRC's review of the list selected
Appendix J as one of seven areas requiring further analysis (NUREG/CR-
4330, Vols. 2 and 3, dated June 1986 and May 1987). The NRC also
conducted a survey of its staff concerning their expertise in a
particular area, experience in regulation, and knowledge of regulatory
requirements. The NRC staff survey identified 54 candidates, a number
of which were previously identified in the earlier survey. The NRC's
assessment of this list also selected appendix J as a potential
candidate for modification.
and May 1987). The NRC also
conducted a survey of its staff concerning their expertise in a
particular area, experience in regulation, and knowledge of regulatory
requirements. The NRC staff survey identified 54 candidates, a number
of which were previously identified in the earlier survey. The NRC's
assessment of this list also selected appendix J as a potential
candidate for modification.

\1\Copies of NUREGs may be purchased from the Superintendent of
Documents, U.S. Government Printing Office, P.O. Box 37082,
Washington, DC 20013/7082. Copies are also available from the
National Technical Information Service, 5285 Port Royal Road,
Springfield, VA 22161. A copy is available for inspection and/or
copying in the NRC Public Document Room, 2120 L Street, NW. (Lower
Level), Washington, DC.
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The NRC published in the Federal Register, for comment, a proposed
revision to appendix J on October 29, 1986 (51 FR 39538) to update
acceptance criteria and test methods based on experience in applying
the existing requirements and advances in containment leak testing
methods, resolve interpretive questions, and reduce the number of
exemption requests. The October 29, 1986, proposed rule is being
withdrawn from further consideration and a more comprehensive proposed
rule that accounts for the latest technical information and regulatory
framework is being proposed.
The NRC's Marginal-to-Safety initiative is part of a broader NRC
initiative for regulatory improvement. Through its Program for
Regulatory Improvement, the NRC has institutionalized an ongoing effort
to eliminate requirements marginal to safety and to reduce regulatory
burden. The NRC staff's plan in SECY-94-090, dated March 31, 1994,
which satisfies the recent requirement for a periodic review of
existing regulations in Executive Order 12866 of September 30, 1993,
was approved by the Commission on May 18, 1994
m for
Regulatory Improvement, the NRC has institutionalized an ongoing effort
to eliminate requirements marginal to safety and to reduce regulatory
burden. The NRC staff's plan in SECY-94-090, dated March 31, 1994,
which satisfies the recent requirement for a periodic review of
existing regulations in Executive Order 12866 of September 30, 1993,
was approved by the Commission on May 18, 1994. The Regulatory
Improvement Program is aimed at the fundamental principle adopted by
the Commission that all regulatory burdens must be justified and that
its regulatory process must be efficient. In practice, this means the
elimination or modification of requirements where burdens are not
commensurate with their safety significance. The activities of the
Regulatory Improvement Program should result in enhanced regulatory
focus in areas that are more safety significant. As a result, an
overall net increase in safety is expected from the program.
The Regulatory Improvement Program will include, whenever feasible
and appropriate, the consideration of performance-oriented and risk-
based approaches. The program will review requirements or license
conditions that are identified as a significant burden on
licensees. If review and analysis find that the
requirements are marginal to safety, they would be eliminated or
relaxed. By performance-oriented, the NRC means establishing regulatory
objectives without prescribing the methods or hardware necessary to
accomplish the objective, and allowing licensees the flexibility to
propose cost-effective methods for implementation. By risk-based, the
NRC means regulatory approaches that use probability risk analysis
(PRA) as the systematic framework for developing or modifying
requirements.
The present rulemaking is part of this overall effort and
initiative for eliminating requirements that are marginal to safety and
is guided by the policies, framework and criteria for the program
ffective methods for implementation. By risk-based, the
NRC means regulatory approaches that use probability risk analysis
(PRA) as the systematic framework for developing or modifying
requirements.
The present rulemaking is part of this overall effort and
initiative for eliminating requirements that are marginal to safety and
is guided by the policies, framework and criteria for the program.
The NRC published a notice in the Federal Register on February 4,
1992 (57 FR 4166), presenting its conclusion that appendix J was a
candidate whose requirements may be relaxed or eliminated based on
cost-benefit considerations. On the basis of NRC staff analyses of
public comments on the proposal, the Commission approved and announced
on November 24, 1992 (57 FR 55156) its plans to initiate rulemaking for
developing a performance-oriented and risk-based regulation for
containment testing requirements. On January 27, 1993, (58 FR 6196) the
NRC staff published a general framework for developing performance-
oriented and risk-based regulations and, at a public workshop on April
27 and 28, 1993, invited discussions of specific proposals for
modifying containment testing requirements. Industry and public
comments on the proposals, and other recommendations and innovative
ideas raised at the public workshop, were documented in the proceedings
of the workshop (NUREG/CP-0129, September 1993). Specifically, the NRC
concluded that the allowable containment leakage rate utilized in
containment testing may be increased and other Appendix J requirements
need not be as prescriptive as the current requirements. To increase
flexibility, the detailed and prescriptive technical requirements
contained in appendix J regulations could be improved and replaced with
performance-based requirements and supporting regulatory guides. The
regulatory guides would allow alternative approaches, although
compliance with current existing regulatory requirements would continue
to be acceptable
e current requirements. To increase
flexibility, the detailed and prescriptive technical requirements
contained in appendix J regulations could be improved and replaced with
performance-based requirements and supporting regulatory guides. The
regulatory guides would allow alternative approaches, although
compliance with current existing regulatory requirements would continue
to be acceptable. The performance-based requirements would reward
superior operating practices.

Performance-Based Regulatory Approach

In institutionalizing the Regulatory Improvement program and
adopting a performance-based regulatory approach, the NRC has
formulated the following framework for revisions to its regulations:
(1) The new performance-based regulation will be less prescriptive
and allow licensees flexibility to adopt cost-effective methods for
implementing the safety objectives of the original rule.
(2) The regulatory safety objectives will be derived, to the extent
feasible and practical, from risk considerations with appropriate
consideration of uncertainties, and will be consistent with the NRC's
Safety Goals.
(3) Detailed technical methods for measuring or judging the
acceptability of a licensee's performance relative to the regulatory
safety objectives will be, to the extent practical, provided in
industry standards and guidance documents which are endorsed in NRC
regulatory guides.
(4) The new regulation will be optional for current licensees so
that licensees can decide to remain in compliance with current
regulations.
(5) The regulation will be supported by necessary modifications to,
or development of, the full body of regulatory practice including, for
example, standard review plans, inspection procedures, guides, and
other regulatory documents.
regulatory guides.
(4) The new regulation will be optional for current licensees so
that licensees can decide to remain in compliance with current
regulations.
(5) The regulation will be supported by necessary modifications to,
or development of, the full body of regulatory practice including, for
example, standard review plans, inspection procedures, guides, and
other regulatory documents.
(6) The new regulation will be formulated to provide incentives for
innovations leading to improvements in safety through better design,
construction, operating, or maintenance practices.

Current Appendix J Requirements

Appendix J to 10 CFR part 50, ``Primary Reactor Containment Leakage
Testing for Water-Cooled Power Reactors,'' became effective on March
16, 1973. The regulatory safety objective of reactor containment design
is stated in 10 CFR part 50, appendix A, ``General Design Criteria for
Nuclear Power Plants,'' Criterion No. 16, ``Containment Design.'' GDC
Criterion 16 mandates ``an essentially leak-tight barrier against the
uncontrolled release of radioactivity to the environment * * *'' for
postulated accidents. Appendix J to 10 CFR part 50 implements, in part,
General Design Criterion No. 16 and specifies containment leakage
testing requirements, including the types of tests required. For each
type of test required, Appendix J specifies how the tests should be
conducted, the frequency of testing, and reporting requirements.
Appendix J requires the following types of containment leak tests:
(1) Measurement of the containment integrated leak-rate (Type A
tests, often referred to as ILRTs).
(2) Measurement of the leak-rate across each pressure-containing or
leakage-limiting boundary for various primary reactor containment
penetrations (Type B tests).
conducted, the frequency of testing, and reporting requirements.
Appendix J requires the following types of containment leak tests:
(1) Measurement of the containment integrated leak-rate (Type A
tests, often referred to as ILRTs).
(2) Measurement of the leak-rate across each pressure-containing or
leakage-limiting boundary for various primary reactor containment
penetrations (Type B tests).
(3) Measurement of the containment isolation valves leak-rates
(Type C tests).
Type B and C tests are referred to as local leak-rate tests
(LLRTs).

Leak-Tightness Requirements

Compliance with 10 CFR part 50, appendix J, requirements is
determined by comparing the measured containment leak-rate with the
maximum allowable leak rate. Maximum allowable leak-rates are
calculated in accordance with 10 CFR Part 100, ``Reactor Site
Criteria,'' and are incorporated into the technical specifications.
Typical allowable leak-rates are 0.1 percent of containment volume per
day for pressurized water reactors (PWRs) and one volume percent per
day for boiling water reactors (BWRs).

Test Frequency Requirements

Schedules for conducting containment leak-rate tests are specified
in appendix J for both preoperational and periodic tests. Periodic
leak-rate tests schedules are as follows:
Type A Tests. (1) After the preoperational leak-rate test, a set of
three Type A tests must be performed at approximately equal intervals
during each 10-year service period. The third test of each set must be
conducted when the plant is shutdown for the 10-year plant in-service
inspection.
(2) The performance of Type A tests must be limited to periods when
the plant facility is nonoperational and secured in the shutdown
condition under the administrative control and in accordance with the
safety procedures defined in the license.
ing each 10-year service period. The third test of each set must be
conducted when the plant is shutdown for the 10-year plant in-service
inspection.
(2) The performance of Type A tests must be limited to periods when
the plant facility is nonoperational and secured in the shutdown
condition under the administrative control and in accordance with the
safety procedures defined in the license.
(3) If any periodic Type A test fails to meet the applicable
acceptance criteria, the test schedule applicable to subsequent Type A
tests will be reviewed and approved by the Commission. If two
consecutive periodic Type A tests fail to meet the applicable
acceptance criteria, a Type A test must be performed at each plant
shutdown for refueling or approximately every 18 months, whichever
occurs first, until two consecutive Type A tests meet the acceptance
criteria, after which time the regular retest schedule may be resumed.

Type B Tests. (1) Except for airlocks, Type B tests must be
performed during reactor shutdown for refueling, or other convenient
intervals, but in no case at intervals greater than 2 years. If opened
following a Type A or B test, containment penetrations subject to Type
B testing must be tested prior to returning the reactor to an operating
mode requiring containment integrity. For primary reactor containment
penetrations employing a continuous leakage monitoring system, Type B
tests, except for tests of airlocks, may be performed every other
reactor shutdown for refueling but in no case at intervals greater than
3 years.
inment penetrations subject to Type
B testing must be tested prior to returning the reactor to an operating
mode requiring containment integrity. For primary reactor containment
penetrations employing a continuous leakage monitoring system, Type B
tests, except for tests of airlocks, may be performed every other
reactor shutdown for refueling but in no case at intervals greater than
3 years.
(2) Airlocks must be tested prior to initial fuel loading and at 6-
month intervals thereafter. Airlocks opened during periods when
containment integrity is not required by the plant's technical
specifications must be tested at the end of such periods. Airlocks
opened during periods when containment integrity is required by the
plant's technical specifications must be tested within 3 days after
being opened. For airlock doors opened more frequently than once every
3 days, the airlock must be tested at least once every 3 days during
the period of frequent openings. For airlock doors having testable
seals, testing the seals fulfills the 3-day test requirement. Airlock
door seal testing must not be substituted for the 6-month test of the
entire airlock at not less than Pa, the calculated peak
containment pressure related to the design basis accident.
Type C Tests. Type C tests must be performed during each reactor
shutdown for refueling but in no case at intervals greater than 2
years.
There have been two amendments to this appendix since 1973. The
first amendment published September 22, 1980 (45 FR 62789), modified
the Type B penetration test requirements to conform to what had become
accepted practice through the granting of exemptions. The second
amendment published November 15, 1988 (53 FR 45890) incorporated the
Mass Point statistical analysis technique as a permissible alternative
to the Total Time and Point-to-Point techniques specified in appendix
J.

European Experience
(45 FR 62789), modified
the Type B penetration test requirements to conform to what had become
accepted practice through the granting of exemptions. The second
amendment published November 15, 1988 (53 FR 45890) incorporated the
Mass Point statistical analysis technique as a permissible alternative
to the Total Time and Point-to-Point techniques specified in appendix
J.

European Experience

A combination of Type A tests and an on-line monitoring (OLM)
capability is being actively pursued in Europe, notably in France and
Belgium, and is currently being considered in Sweden. OLM is used to
identify a ``normal'' containment pressurization pattern and to detect
deviations from that pattern. The Belgians conduct a leak test using
OLM during reactor operation after each cold shutdown longer than 15
days with the objective of detecting gross leaks. The objective of the
Belgian approach to Type A testing is to reduce the frequency and
duration of the tests. The Type A test is conducted at a containment
pressure (Pt) not less than half of the peak pressure (0.5
Pa). It is performed once every 10 years.
In France, containment leaktightness is being continuously
monitored during reactor operation in all of the French PWR plants
using the SEXTEN system. It is also being evaluated by the Swedes for
their PWR units. Leaks may be detected during the positive or negative
pressure periods in the containment by evaluating the air mass balance
in the containment. Type A tests are conducted at containment peak
pressure (loss-of-coolant accident pressure) before initial plant
startup, during the first refueling, and thereafter every 10 years
unless a degradation in containment leak-tightness is detected. In that
case, tests are conducted more frequently.
Further details of European approaches to containment testing is
provided in Draft NUREG-1493.

Advance Notices for Rulemaking and Public Comments
pressure (loss-of-coolant accident pressure) before initial plant
startup, during the first refueling, and thereafter every 10 years
unless a degradation in containment leak-tightness is detected. In that
case, tests are conducted more frequently.
Further details of European approaches to containment testing is
provided in Draft NUREG-1493.

Advance Notices for Rulemaking and Public Comments

Over time, it has become apparent that variations in plant design
and operation frequently make it difficult to meet some of the
requirements contained in appendix J because of its prescriptive
nature. Economic and occupational exposure costs are directly related
to the frequency of containment testing. Containment integrated leak
rate tests (Type A) preclude any other reactor maintenance activities
and thus are on the critical path for return to service from reactor
outages. In addition to the costs of the tests, integrated leak tests
impose the added burden of the cost of replacement power. Containment
penetration leak tests (Type B and C) can be conducted during reactor
shutdowns in parallel with other activities and thus tend to be less
costly; however, the large number of penetrations impose a significant
burden on the utilities. Additionally, risk assessments performed to
date indicate that the allowable leak rate from containments can be
increased, and that control of containment leakage at the current low
rates is not as risk significant as previously assumed.2 3
in parallel with other activities and thus tend to be less
costly; however, the large number of penetrations impose a significant
burden on the utilities. Additionally, risk assessments performed to
date indicate that the allowable leak rate from containments can be
increased, and that control of containment leakage at the current low
rates is not as risk significant as previously assumed.2 3

\2\Severe Accident Risks: An assessment for five U.S. Nuclear
Power Plants, Final Summary Report.'' NUREG-1150, December 1990.
Copies of NUREGs may be purchased from the Superintendent of
Documents, U.S. Government Printing Office, P.O. Box 37082,
Washington, DC 20013/7082. Copies are also available from the
National Technical Information Service, 5285 Port Royal Road,
Springfield, VA 22161. A copy is available for inspection and/or
copying in the NRC Public Document Room, 2120 L Street, NW. (Lower
Level), Washington, DC.
\3\Performance-Based Containment Leak Test Program,'' Draft
NUREG-1493, January 1995. A free single copy of draft-1493 may be
requested by those considering public comment by writing to the U.
S. Nuclear Regulatory Commission, ATTN: Distribution Section, Room
P1-37, Washington, DC 20555. A copy is also available for inspection
and/or copying in the NRC Public Document Room, 2120 L Street, NW.
(Lower Level), Washington, DC 20555.
---------------------------------------------------------------------------

Initial NRC Proposal

In August of 1992, the Commission initiated a rulemaking to modify
appendix J to make it less prescriptive and more performance-oriented.
The Commission also initiated a plan to relax the allowable containment
leak-rate utilized to define performance standards for containment
tests. In the Federal Register published on January 27, 1993 (58 FR
6196), the NRC indicated the following potential modifications to
appendix J of 10 CFR part 50 would be considered:
appendix J to make it less prescriptive and more performance-oriented.
The Commission also initiated a plan to relax the allowable containment
leak-rate utilized to define performance standards for containment
tests. In the Federal Register published on January 27, 1993 (58 FR
6196), the NRC indicated the following potential modifications to
appendix J of 10 CFR part 50 would be considered:
(1) Increase allowable containment leak-rates based on Safety Goals
and PRA technology (i.e., define a new performance standard).
(2) Modify appendix J to be a performance-based regulation:
A Limit the revised rule to a new regulatory objective: In order
to ensure the availability of the containment during postulated
accidents, licensees should either:
(i) Test overall containment leakage at intervals not longer than
every 10 years, and test pressure-containing or leakage-limiting
boundaries and containment isolation valves on an interval based on the
performance history of the equipment; or
(ii) Provide on-line (i.e., continuous) monitoring of containment
isolation status.
B Remove prescriptive requirements from appendix J and preserve
useful portions as guidance in a NRC regulatory guide.
C Endorse industry standards on:
(i) Guidance for calculating plant-specific allowable leak-rates
based on new NRC performance standard;
(ii) Guidance on the conduct of containment tests; and
(iii) Guidance for on-line monitoring of containment isolation
status.
D Continue to accept compliance with the current detailed
requirements in appendix J (i.e., licensees presently in compliance
with Appendix J will not need to do anything if they do not wish to
change their practice).
A public workshop on the subject was held by the NRC on April 27
and 28, 1993.4

\4\``Workshop on Program for Elimination of Requirements
Marginal to Safety.'' NUREG/CP-0129, September 1994.
---------------------------------------------------------------------------

Public Comments and Issues
pliance
with Appendix J will not need to do anything if they do not wish to
change their practice).
A public workshop on the subject was held by the NRC on April 27
and 28, 1993.4

\4\``Workshop on Program for Elimination of Requirements
Marginal to Safety.'' NUREG/CP-0129, September 1994.
---------------------------------------------------------------------------

Public Comments and Issues

Listed below are the categories of relevant issues identified by
the public, the nuclear industry, and the NRC at the public workshop
and in response to earlier solicitations for comments on this
rulemaking, and a summary of interests expressed. Summaries of
individual comments earlier solicitations were published on November
1992 (57 FR 55156). The comments at the public workshop are documented
in NUREG/CP-0129, September 1993. The comments are available for
inspection in the NRC Public Document Room.
1. Is there a continuing need for this regulation?
Most commenters agree that there is a continuing need for a
regulation on containment leak testing. While some commenters believe
the regulation should be tightened, most commenters believe appendix J
requirements should be relaxed. Industry representatives presented a
wealth of data on the cost and benefits of containment leak testing.
2. Should the NRC replace appendix J to 10 CFR part 50, ``Primary
Reactor Containment Leak Testing for Water-Cooled Power Reactors,''
with a non-prescriptive, performance-based rule?
One commenter believed that using conservatism that may far exceed
performance-based regulations is in the public's interest. Some
misallocation of resources does exist that could be corrected, although
there may be varying opinions concerning where they are. One commenter
believed that, from a public perception viewpoint, there would be
dissatisfaction with changing to performance-based regulation. It
appears to represent a streamlining or deregulation of standards
nce-based regulations is in the public's interest. Some
misallocation of resources does exist that could be corrected, although
there may be varying opinions concerning where they are. One commenter
believed that, from a public perception viewpoint, there would be
dissatisfaction with changing to performance-based regulation. It
appears to represent a streamlining or deregulation of standards.
Another view held that because there is no consistent regulatory basis,
there are inconsistencies in regulation. Performance-based regulations
would get rid of these inconsistencies. A move to performance-based
regulations would uncover marginal requirements. Performance-based
requirements would depend on the functional importance of a component
and might include deterministic performance standards for components. A
component that did not meet the performance standard would be rejected.
Another view was that the industry can use increased knowledge about
reactors and regulations within the existing technology to improve the
regulations and reduce risk, without relying on risk assessments. This
approach might result in earlier benefits. Industry generally
encouraged the NRC to proceed with its initiative to decrease the
prescriptiveness of its regulations and adopt more performance-based
approaches.
3. Should the NRC increase allowable containment leakage rates?
Some commenters believe that the existing appendix J requirements
for allowable leakage should not be relaxed and, based on their
interpretation of NUREG/CR-5747, ``Estimate of Radionuclide Releases
Characteristics into Containment Under Severe Accident Conditions,''
suggests that more stringent leakage limits, not relaxation of these
requirements, is appropriate. Because the current leakage rates
specified in plant technical specifications are based on relatively
conservative assumptions, the majority of commenters believe that a
more realistic representation of loss-of-coolant accidents should be
used to calculate dose to the public
ident Conditions,''
suggests that more stringent leakage limits, not relaxation of these
requirements, is appropriate. Because the current leakage rates
specified in plant technical specifications are based on relatively
conservative assumptions, the majority of commenters believe that a
more realistic representation of loss-of-coolant accidents should be
used to calculate dose to the public. These commenters believe that
more realistic accident scenarios would support a relaxation in the
containment leak-rate.
4. Should the NRC decrease Type A, B, and C test frequencies?
While some commenters had opinions on proper test frequencies, and
most believed that test frequencies could be relaxed, overall, the
technical community believed that examination of the technical data and
the objectives of the test should be used to determine the appropriate
test frequency. One commenter believed that both increased and
decreased frequencies might be appropriate. For example, tests might be
increased in frequency for valves that play a risk-significant role,
and test interval or allowable leak-rate could be increased for less
important components.
5. Can the new rule and its implementation yield an equivalent
level of, or only have a marginal impact on, safety?
Most commenters believe that a move to performance-based
regulations would uncover marginal requirements. Some believe that by
conserving resources in areas where safety is not a significant issue,
more resources can be devoted to more risk-significant areas with a net
increase in the overall safety margin.
6
mentation yield an equivalent
level of, or only have a marginal impact on, safety?
Most commenters believe that a move to performance-based
regulations would uncover marginal requirements. Some believe that by
conserving resources in areas where safety is not a significant issue,
more resources can be devoted to more risk-significant areas with a net
increase in the overall safety margin.
6. Can the regulatory/safety objective (qualitative or
quantitative) be established in an objective manner to allow a common
understanding between licensees and the NRC on how the performance or
results will be measured or judged?
Several commenters believe that the regulatory process should
integrate deterministic, risk-based, and performance-based regulation
and allow for case-specific evaluation, with a goal of protecting the
health and safety of the public and at the same time minimizing the
cost to the licensee. Others believe that the opinions of public
interest groups should also be sought in deriving safety goals/
objectives. Overall, no comments were presented that would suggest that
a common understanding could not be achieved on goals and performance
measurements.
7. Can the regulation and implementation documents be developed in
such a manner that they can be objectively and consistently inspected
and enforced against?
Several commenters believe that the regulations should be
performance-based and the associated guidance documents should be
prescriptive so that only the guidance documents not the regulations
will need to be changed as more information is gained on compliance
issues. Many commenters believe that PRAs should not be the sole basis
for regulatory decisions due to the uncertainty in their results;
however, if the results indicate that a particular requirement has a
contribution to risk significantly below the Safety Goal thresholds,
the PRA information should be considered sufficient to justify
elimination of the requirement as marginal to safety.

Proposed Revision
mmenters believe that PRAs should not be the sole basis
for regulatory decisions due to the uncertainty in their results;
however, if the results indicate that a particular requirement has a
contribution to risk significantly below the Safety Goal thresholds,
the PRA information should be considered sufficient to justify
elimination of the requirement as marginal to safety.

Proposed Revision

Based on several advance notices for rulemaking and significant
public comment and discussion, risks and costs evaluated, and
consideration of which modifications are feasible and practical at this
time, the NRC proposes two phases for modifications of requirements to
containment leakage testing. The first phase, for which modifications
are proposed in this notice, will allow leak-rate testing intervals to
be based on the performance of the containment system structures and
components. The second phase will further examine the needed
requirements of the containment function (i.e. structural and leak-
tight integrity of containment system structures and components, and
prevention of inadvertent bypass), and include consideration of the
potential of on-line monitoring of containment integrity
to verify certain functions. Solicitation of public comments to guide
this future work is included later in this notice.
The rule proposed in this notice would apply to all NRC licensees
who operate light water power reactors. The proposed rule would allow
licensees the option of continuing to comply with the current appendix
J or to adopt the new performance-based standards.
The NRC's analyses are based upon the insight gained through the
use of probability risk assessment techniques and the significant data
base of practical, hands-on operating experience gained since appendix
J was promulgated in 1973. This operating experience provides hard
evidence of the activities necessary to conduct appendix J testing, and
the costs of those activities both in monetary terms and occupational
radiation exposure
sight gained through the
use of probability risk assessment techniques and the significant data
base of practical, hands-on operating experience gained since appendix
J was promulgated in 1973. This operating experience provides hard
evidence of the activities necessary to conduct appendix J testing, and
the costs of those activities both in monetary terms and occupational
radiation exposure.
The results of the present effort documented in draft NUREG-1493,
which are based on NUREG-1150, confirm previous observations of
insensitivity of population risks from severe reactor accidents to
containment leak-rates.
The current appendix J requirements have achieved the regulatory
criteria of assuring an essentially leak-tight boundary between the
power reactor system and the external environment (GDC Criterion 16).
Costs associated with complying with current appendix J requirements
are estimated to be $165,000 for a complete battery of Type B/C tests
and $1,890,000 for Type A tests. Over the average reactor's remaining
lifetime of 20 years, the present value of all remaining leak testing
at a five percent discount rate is about $7 million per reactor.
Estimates of the remaining industry-wide costs of implementing current
appendix J requirements range from $720 to $1,080 million,
approximately 75 percent of which could be averted with a performance-
based rule.
The present study found that by allowing requirements with marginal
effect on safety, but which impose a significant cost on licensees, to
remain in effect is to essentially misallocate a portion of the NRC's
and the industry's resources on activities for which there is no
commensurate return in safety. The real cost then may be in a missed
opportunity to focus NRC and licensee efforts to areas where the return
in terms of added public safety is higher.
Specific alternatives for modifying the current appendix J were
identified by the public in response to the NRC's Federal Register
notice published on January 27, 1993 (58 FR 6196)
ivities for which there is no
commensurate return in safety. The real cost then may be in a missed
opportunity to focus NRC and licensee efforts to areas where the return
in terms of added public safety is higher.
Specific alternatives for modifying the current appendix J were
identified by the public in response to the NRC's Federal Register
notice published on January 27, 1993 (58 FR 6196). Those whose
characteristics matched the NRC's established criteria for the marginal
to safety program were selected for further review.
Modifications of Initial Proposals

Allowable Leakage Rate

The NRC had initially planned to establish, by rulemaking, a risk-
based allowable leak-rate commensurate with its significance to total
public risk. Specific findings from draft NUREG-1493 on the allowable
leakage rate include:
1. Allowable leakage can be increased approximately two orders of
magnitude (100-200 fold) with marginal impact on population dose
estimates from reactor accidents.
2. Calculated mean population risks are several orders of magnitude
below the NRC's Safety Goals for all reactors considered, but the tail
of the distribution can approach Safety Goals.
3. Increases in the allowable leak-rate is estimated to have a
negligible impact on occupational exposure.
Relaxing the allowable leak-rate is estimated to reduce future
industry testing costs by $50 to $110 million, a ten percent decrease
in overall leak-rate testing costs.
A risk-based allowable leakage rate would be based on an
evaluation, using PRA, of the sensitivity and significance of
containment leakage to risk, and determining an appropriate containment
leakage limit commensurate with its significance to the risk to the
public and plant control room operators
esting costs by $50 to $110 million, a ten percent decrease
in overall leak-rate testing costs.
A risk-based allowable leakage rate would be based on an
evaluation, using PRA, of the sensitivity and significance of
containment leakage to risk, and determining an appropriate containment
leakage limit commensurate with its significance to the risk to the
public and plant control room operators. However, this would entail a
major change in policy and restructuring of the current licensing basis
and a more complete understanding of the uncertainties associated with
the threat of severe accidents to the containment, and therefore, the
NRC plans to consider a modification of the performance standard
(allowable leakage level) in the second phase separate from
modifications of testing requirements. This modification will be part
of a broader effort to further examine the risk significance of various
attributes of containment performance, i.e. structural and leak-tight
integrity of containment system structures and components, and
inadvertent bypass.

On-Line Monitoring (OLM) Systems

Currently, there is no requirement for OLM systems which monitor
the containment to detect unintentional breaches of containment
integrity.
Studies discussed in draft NUREG-1493, ``Performance-Based
Containment Leak Test Program,'' find that, based on operating
experience, OLM would not significantly reduce the risk to the public
from nuclear plant operation and, thus, cannot be justified solely on
risk-based considerations. Specific findings include:
1. Continuous monitoring methods that exist appear technically
capable of detecting leaks in reactor containments within 1 day to
several weeks. OLM systems are in use or planned in several European
countries.
2. OLM systems are only capable of detecting leaks in systems that
are open to the containment atmosphere during normal operation
(approximately ten percent of the mechanical penetrations).
3
nuous monitoring methods that exist appear technically
capable of detecting leaks in reactor containments within 1 day to
several weeks. OLM systems are in use or planned in several European
countries.
2. OLM systems are only capable of detecting leaks in systems that
are open to the containment atmosphere during normal operation
(approximately ten percent of the mechanical penetrations).
3. The technical and administrative objectives of OLM systems and
Type A tests are different.
4. OLM cannot be considered as a complete replacement for Type A
tests because it cannot challenge the structural and leak-tight
integrity of the containment system at elevated pressures.
5. Analysis of the history of operating experience indicates
limited need for, and benefit of, OLM in the U.S.
Although OLM cannot be justified solely based on risk
considerations, a plant already possessing such a system has greater
assurance of achieving certain attributes of containment integrity.
Therefore, OLM systems could contribute towards an overall leakage
monitoring scheme. Some capability for on-line monitoring already
exists as a byproduct of specific containment designs. For example,
licensees with inerted BWR containments, or subatmospheric PWR
containments, would readily detect gross leakages that develop during
normal operation.
Given that the application of on-line monitoring is specific to
containment design, and generic application cannot be justified solely
on risk considerations, the NRC does not propose a requirement for
OLMs. However, licensees which already have such a capability (e.g.
inerted BWR containments, and subatmospheric PWR containments) are
encouraged to propose plant-specific application of such a capability,
including credit for any added assurance for certain attributes of
containment integrity provided by such a system compared to other
testing methods. The NRC will reconsider the role of OLM in the second
phase of modifications in this area along with the allowable leakage
rate
nts, and subatmospheric PWR containments) are
encouraged to propose plant-specific application of such a capability,
including credit for any added assurance for certain attributes of
containment integrity provided by such a system compared to other
testing methods. The NRC will reconsider the role of OLM in the second
phase of modifications in this area along with the allowable leakage
rate.

Proposed Modification of Type A, B, C Test Intervals

The NRC proposes at this time, for the first phase of
modifications, to define a new risk-based regulation by utilizing the
performance history of components (containment,
penetrations, valves) as the means to justify an increase in the
testing interval for Type A, B, and C tests. The revised regulation
would require tests to be conducted on an interval based on the
performance of the containment structure, penetration or valves without
specifying the interval in the regulation. Currently, three Type A
tests are conducted in every 10 year period. Type B (except airlocks,
which are tested more frequently) and C tests are conducted on a
frequency not to exceed 2 years.
The NRC proposes to base the frequency of Type A tests (ILRTs) on
the historical performance of the overall containment system. Specific
findings documented in draft NUREG-1493 that justify the proposal
include:
1. The fraction of leakages detected only by ILRTs is small, on the
order of a few percent.
2. Reducing the frequency of ILRT testing from three per 10 years
to one per 10 years leads to a marginal increase in risk.
3. ILRTs also test the strength of the containment structure. No
alternative to ILRTs have been identified to provide assurance that the
containment structure will meet allowable leakage rates during design-
basis accidents.
4. At a frequency of one test per 10 years, industry-wide
occupational exposure would be reduced by 0.087 person-sievert (8.7
person-rem) per year
inal increase in risk.
3. ILRTs also test the strength of the containment structure. No
alternative to ILRTs have been identified to provide assurance that the
containment structure will meet allowable leakage rates during design-
basis accidents.
4. At a frequency of one test per 10 years, industry-wide
occupational exposure would be reduced by 0.087 person-sievert (8.7
person-rem) per year.
Based on specific, detailed analyses of data from the North Anna
and Grand Gulf plants and data from twenty-two nuclear plants (see
draft NUREG-1493), performance-based alternatives to current LLRT
methods are feasible with marginal impact on risk. Specific findings
that justify the proposal include:
1. Type B and C tests detect a very large fraction, over 97 percent
of containment leakages.
2. Of the 97%, virtually all leakages are identified by LLRTs of
containment isolation valves (Type C tests).
3. Based on the detailed evaluation of the experience of a single
2-unit station, no correlation of failures with type of valve or plant
service could be found.
4. For the 20 years of remaining operations, changing the Type B/C
test frequency alone is estimated to reduce industry-wide occupational
exposure by 0.72 person-sievert (72 person-rem) per year. If 20-year
license extension is assumed, the estimate is 0.75 person-sievert (75
person-rem) per year.
Reducing the frequency of ILRTs will reduce future industry testing
costs by approximately $330 to $660 million if tests are conducted once
per 10 years versus the current three per ten years. These savings
represent about 65 percent of the remaining costs of current appendix J
requirements. Performance-based LLRT alternatives are estimated to
reduce future industry testing costs by $40 million to $55 million.
These savings represent about five percent of the total remaining costs
of appendix J testing
f tests are conducted once
per 10 years versus the current three per ten years. These savings
represent about 65 percent of the remaining costs of current appendix J
requirements. Performance-based LLRT alternatives are estimated to
reduce future industry testing costs by $40 million to $55 million.
These savings represent about five percent of the total remaining costs
of appendix J testing.
Therefore, based on the risks and costs evaluated, and other
considerations discussed above, a performance-based appendix J which
encompasses the following principles which differ moderately from those
first described in the Federal Register (January 27, 1993 58 FR 6197)
is proposed:
General. (1) Make appendix J less prescriptive and more
performance- oriented; (2) Move details of appendix J tests to a
regulatory guide as guidance; (3) Endorse approved industry guideline
(NEI 94-01) on guidance on the conduct of containment tests in a
regulatory guide. The methods for testing are contained in an industry
standard (ANSI/ANS 56.8-1994) which is referenced in the NEI guideline;
(4) Allow voluntary adoption of the new regulation, i.e., current
detailed requirements in appendix J will continue to be acceptable for
compliance with the modified rule.
Leakage Limits. Acknowledge the less risk-significant nature of
allowable containment leakage (La) but pursue its modification as
a separate action.
Type A Test Interval
6.8-1994) which is referenced in the NEI guideline;
(4) Allow voluntary adoption of the new regulation, i.e., current
detailed requirements in appendix J will continue to be acceptable for
compliance with the modified rule.
Leakage Limits. Acknowledge the less risk-significant nature of
allowable containment leakage (La) but pursue its modification as
a separate action.
Type A Test Interval. (1) Based on the limited value of integrated
leak-rate tests (ILRTs) in detecting significant leakages from
penetrations and isolation valves, establish the test interval based on
the performance of the containment system structure; (2) The
performance criterion of the test will continue to be the allowable
leakage rate (La); (3) The industry guideline allows extension of the
Type A test interval to once every 10 years based on satisfactory
performance of two previous tests; (4) In the regulatory guide, the NRC
has included an exception for the extension of the interval of the
general visual inspection of the containment system, and limited the
interval to three times every 10 years as is current practice.
Type B & C Test Interval. (1) Allow local leak-rate test (LLRTs)
intervals to be established based on the experience history of each
component; (2) The performance criterion for the tests will continue to
be the allowable leakage rate (La); (3) Specific performance criteria
and factors for establishing extended test intervals (up to 10 years
for Type B components, and 5 years for Type C components) are contained
in the regulatory guide and industry guideline. In the regulatory
guide, the NRC has included an exception to the extension of Type C
test intervals up to 10 years that is proposed in the NEI industry
guideline, and limited such extensions to 5-years.
Specific Areas for Public Comment
tended test intervals (up to 10 years
for Type B components, and 5 years for Type C components) are contained
in the regulatory guide and industry guideline. In the regulatory
guide, the NRC has included an exception to the extension of Type C
test intervals up to 10 years that is proposed in the NEI industry
guideline, and limited such extensions to 5-years.
Specific Areas for Public Comment

In its preliminary criteria for developing performance-based
regulations, the NRC identified three issues to be addressed by the
rulemaking process as a measure of the viability of the revised rule.
These issues have been addressed in the rulemaking package and the NRC
is seeking further public input on them.
1. Can the new rule and its implementation yield an equivalent
level of, or would it only have a marginal impact on, safety?
The present study analyzed risks to the population and to workers
from changes in appendix J requirements. The results of the present
analysis confirm that population risks from severe reactor accidents
are not sensitive to containment leak-rates. The calculated risks are
well below the Safety Goals for all of the reactors considered even at
assumed containment leak-rates 100-fold above current requirements. A
change in the allowable leak-rate is estimated to have a negligible
impact on occupational exposure. Results also show that relaxing the
frequency of Type A, B, and C tests leads to an increase in overall
reactor risk of approximately two percent. This increase is considered
to be marginal to safety. Due to limitations of available plant data,
the uncertainties of the risk impact of extending Type C test intervals
beyond sixty months needs to be addressed.
Costs associated with complying with current appendix J
requirements are estimated to be $165,000 for a complete battery of
Type B/C tests, and $1,890,000 for Type A tests
e based objectively upon
the performance history of components as analyzed by established
methods.
To assist in the common understanding of new methods of
establishing Type A, B and C test frequencies between the NRC and power
reactor licensees, the NRC has had ongoing discussions with licensees.
These discussions included participation in workshops designed to
elicit a common understanding. From these efforts, the NRC is proposing
to endorse a guidance document from industry which specifies acceptable
methods for achieving compliance with Appendix J.
Further, the NRC proposes to require that plant technical
specifications provide a general reference to the regulatory guide or
other implementation document to ensure the prior review and approval
by the NRC of licensee deviations from approved methods. This will help
maintain a common understanding in the implementation of the
performance-based rule, and ensure adequate basis for licensee
deviations.
The NRC expects that its activities to date, the review and
endorsement of a industry guideline in a regulatory guide, and the
general reference of the regulatory guide in plant technical
specifications, will establish regulatory safety objectives in an
objective manner, and provide a common understanding on the measures of
compliance.
3. Can the regulation and implementation documents be developed in
such a manner that they can be objectively and consistently inspected
and enforced against?
A guidance document developed by industry and approved for use by
the NRC helps to ensure consistent interpretation and application of
compliance requirements. As experience is gained under the new rule,
adjustments may be reasonably anticipated to the industry's guidance
document which will be reviewed and approved by the NRC through the
regulatory guide revision process. The NRC's regulatory and inspection
personnel shall be trained in the interpretation and use of all
relevant implementation documents to assure consistent enforcement
equirements. As experience is gained under the new rule,
adjustments may be reasonably anticipated to the industry's guidance
document which will be reviewed and approved by the NRC through the
regulatory guide revision process. The NRC's regulatory and inspection
personnel shall be trained in the interpretation and use of all
relevant implementation documents to assure consistent enforcement.
In addition to the above, the NRC solicits comments on the
following two issues.
4. Should the proposed revision be made even less prescriptive?
The proposed rule is less prescriptive than existing requirements
and provides licensees with greater flexibility in the implementation
of safety objectives established by NRC. This action is proposed based
on substantive technical analyses presented in draft NUREG-1493.
Regulatory positions were developed by the NRC through insights from
probabilistic risk analyses, operating data, and deterministic
engineering considerations. The NRC solicits public comment on whether
this revision should make the rule even less prescriptive than proposed
in this notice; and if so, how?
Specifically, comments are solicited on the potential alternative
of further relaxing the test frequency requirements for the Integrated
Leak Rate Tests (ILRT) by establishing a fixed ten-year interval based
on generic industry data, or perhaps eliminating the tests beyond the
first pre-operational test. Analyses of historical test data and risk
analyses presented in draft NUREG-1493 indicate that the ILRT interval
could be extended beyond the proposed ten-year interval, and perhaps
eliminated after the first pre-operational test with marginal impact on
safety. Leakages detected by an ILRT are rare and random, and not
generally related to previous performance at a plant. However, the NRC
considers that a ten-year testing interval, based on satisfactory
previous plant-specific performance, is appropriate at this time
nded beyond the proposed ten-year interval, and perhaps
eliminated after the first pre-operational test with marginal impact on
safety. Leakages detected by an ILRT are rare and random, and not
generally related to previous performance at a plant. However, the NRC
considers that a ten-year testing interval, based on satisfactory
previous plant-specific performance, is appropriate at this time. It is
consistent with current industry practice for testing of pressure
vessels, and should detect the potential for aging mechanisms that
could affect containment leaktightness. Historical test data have not
yet shown evidence of such aging mechanisms but they might develop late
in life where little data exists. Comments are solicited on other
benefits provided by the ILRT, in addition to determining the leakage
rate, that would need to be addressed to justify further relaxations or
elimination of the test. NRC's current position is guided by the desire
to maintain some conservatism to address uncertainties and adopt an
evolutionary approach in the modification of its requirements. However,
the NRC does not wish to maintain undue conservatism in its
regulations, and therefore, will consider comments received to
determine the degree of prescriptiveness, and any further relaxation of
the ILRT requirements included in the final rule.
5. Should the proposed revisions be made mandatory?
The NRC is considering whether the proposed rule, which as
currently proposed would provide licensees with a non-mandatory
alternative to their existing appendix J containment leak testing
program, should instead be adopted as a mandatory requirement for all
licensees
further relaxation of
the ILRT requirements included in the final rule.
5. Should the proposed revisions be made mandatory?
The NRC is considering whether the proposed rule, which as
currently proposed would provide licensees with a non-mandatory
alternative to their existing appendix J containment leak testing
program, should instead be adopted as a mandatory requirement for all
licensees.
The proposed rule is drafted as a non-mandatory alternative to
current appendix J requirements because the Staff recognized that some
licensees may have technical programs which they may not wish to modify
at this time, even though a proposed modification would constitute a
``relaxation'' from current requirements or provide other regulatory or
economic benefit. For these reasons, the Commission earlier approved a
Staff policy whereby any proposed revisions to existing NRC
requirements developed by the Regulatory Improvement Program (See SECY-
94-090, ``Institutionalization of Continuing Program for Regulatory
Improvement,'' March 31, 1994) would not be mandatory, but would be
proposed as alternatives (options) to existing requirements which may
be voluntarily adopted by licensees. Given the history of difficulty
and low success rate for attempts to resolve new safety issues
simultaneously with improvements to regulatory efficiency, the
Commission also approved a Staff policy for separating regulatory
actions for new safety issues from those for improving regulatory
efficiency. Therefore, this proposed rule does not address any new
safety issues beyond the scope of the current appendix J requirements
and is not aimed at improving safety.
The NRC is interested in the public's view as to whether the
proposed rule should be made mandatory, in light of the overall long-
term reduction in regulatory burden on licensees and the marginal
impact on safety which would be entailed in the relaxation (see
previous discussion in ``Proposed Modification of Type A, B, C Test
Intervals)
x J requirements
and is not aimed at improving safety.
The NRC is interested in the public's view as to whether the
proposed rule should be made mandatory, in light of the overall long-
term reduction in regulatory burden on licensees and the marginal
impact on safety which would be entailed in the relaxation (see
previous discussion in ``Proposed Modification of Type A, B, C Test
Intervals). The NRC is interested in the public's views on using the
increase in regulatory efficiency as a potential rationale for making
the proposed rule mandatory for all licensees. The NRC also requests
public comment on the underlying policy discussed above that NRC
rulemakings which are not intended to increase safety, but are only
intended to increase regulatory efficiency and reduce the regulatory
burden imposed by the NRC's rules, should be adopted as
alternatives to existing requirements which may be voluntarily adopted
by the regulated entity.
The NRC recognizes that if the proposed rule were made mandatory,
that several backfitting issues are raised. These backfitting concerns
are discussed in more detail in the next section on the ``Backfit
Rule.''
Backfit Rule

As discussed above, the Commission is considering whether the
proposed rule, which is currently drafted as providing licensees with a
non-mandatory alternative relaxing the requirements for and frequency
of containment leakage testing, should be adopted as a mandatory
requirement (that is, the requirements of the rule would be imposed on
all nuclear power plant licensees). If the alternative is made
mandatory, the Commission acknowledges the potential relevance of the
Backfit Rule. The Commission believes that the Backfit Rule was
intended to constrain the Commission's adoption of mandatory
relaxations of Commission requirements, if the mandated change imposed
costs upon the licensee and that such mandatory relaxations are
``backfits'' as defined in Sec. 50.109(a)(1)
alternative is made
mandatory, the Commission acknowledges the potential relevance of the
Backfit Rule. The Commission believes that the Backfit Rule was
intended to constrain the Commission's adoption of mandatory
relaxations of Commission requirements, if the mandated change imposed
costs upon the licensee and that such mandatory relaxations are
``backfits'' as defined in Sec. 50.109(a)(1). However, the Commission
believes that it has the authority and basis for ``waiving'' the
application of the Backfit Rule to the adoption of this rulemaking. The
Commission requests public comments on each of these points.

1. The Proposed Rule Constitutes a ``Backfit''

The current version of the Backfit Rule, 10 CFR 50.109, was adopted
in substantially its current form in 1985.5 50 FR 38097 (September
20, 1985). Based upon a review of the rulemaking record which led to
the final 1985 rule, the Commission's objective in adopting the Backfit
Rule was to prevent the imposition of new requirements, not otherwise
needed to assure adequate protection or compliance, which were of
marginal overall safety benefit or involved implementation costs which
were out of proportion to the safety benefits. The SOC explained that
under the new backfitting standard ``the Commission would not
ordinarily expect that safety improvements would be required as
backfits which result in an insignificant or small benefit to the
public health and safety or common defense and security, regardless of
the implementation costs'' (50 FR at 38102). Thus, the aim of the
Backfit Rule was to instill into the regulatory process the need for
disciplined analysis of proposed new requirements and regulatory
initiatives (See generally 50 FR at 38101-38102).
ired as
backfits which result in an insignificant or small benefit to the
public health and safety or common defense and security, regardless of
the implementation costs'' (50 FR at 38102). Thus, the aim of the
Backfit Rule was to instill into the regulatory process the need for
disciplined analysis of proposed new requirements and regulatory
initiatives (See generally 50 FR at 38101-38102).

\5\The Backfit Rule was subsequently amended in 1988 (53 FR
20603, June 6, 1988) in response to a decision of the U.S. Court of
Appeals for the D.C. Circuit Union of Concerned Scientists et al. v.
U.S. Nuclear Regulatory Commission, 824 F.2d 103) which remanded the
1985 rule to the NRC because the rule failed to clearly indicate
that costs may not be a consideration in determining whether there
is adequate protection to the public health and safety.
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The proposed revision relaxes and modifies existing requirements
where the Commission believes that the burdens are not commensurate
with their safety significance. Furthermore, the proposed rule does not
contain any new requirements to address new safety issues not addressed
in the original Appendix J rulemaking. However, if imposed as a
mandatory requirement the proposed rule would mandate changes in a
licensee's program for conducting containment leak rate tests, and
would impose short-term costs on the licensee in order to reduce the
long-term regulatory burden. However desirable such an imposition may
be over the long term, it would nonetheless constitute a ``backfit'' as
defined in Sec. 50.109(a)(1). However, the Commission requests public
comment on whether the definition of ``backfit'' in Sec. 50.109(a)(1)
was intended to encompass rulemakings of the type represented by this
proposed rule.

2. Waiving the Applicability of the Backfit Rule
burden. However desirable such an imposition may
be over the long term, it would nonetheless constitute a ``backfit'' as
defined in Sec. 50.109(a)(1). However, the Commission requests public
comment on whether the definition of ``backfit'' in Sec. 50.109(a)(1)
was intended to encompass rulemakings of the type represented by this
proposed rule.

2. Waiving the Applicability of the Backfit Rule

The Commission adopted the Backfit Rule as a self-imposed
limitation on its rulemaking authority, and under the appropriate
circumstances the Commission may ``waive'' its applicability, subject
to the Administrative Procedure Act's requirement in rulemaking for
notice and opportunity for public comment. The Commission believes that
it is appropriate to ``waive'' the applicability of the Backfit Rule to
the proposed rule if its requirements were made mandatory. The purpose
of the rule is to relax and modify existing containment leak rate
testing requirements where burdens are not commensurate with their
safety significance. It does not contain any new requirements to
address new safety issues not addressed in the original appendix J
rulemaking. The proposed revision would relax existing marginal-to-
safety requirements in order to reduce regulatory burden on nuclear
power plant licensees and increase regulatory efficiency. This type of
rulemaking complements the objectives of the Backfit Rule by
eliminating requirements with little or no positive impact on safety,
but whose regulatory burden is substantial. Therefore, if the
Commission determines to impose the proposed rule's requirements, the
Commission proposes to ``waive'' this rule from the requirements of the
Backfit Rule.
The Commission requests public comment on the proposed rationale
for ``waiving'' the application of the Backfit Rule to this rulemaking.

Regulatory Guide; Issuance, Availability
ut whose regulatory burden is substantial. Therefore, if the
Commission determines to impose the proposed rule's requirements, the
Commission proposes to ``waive'' this rule from the requirements of the
Backfit Rule.
The Commission requests public comment on the proposed rationale
for ``waiving'' the application of the Backfit Rule to this rulemaking.

Regulatory Guide; Issuance, Availability

A draft regulatory guide, temporarily identified by its task number
DG-1037, (on the same subject) ``Performance-Based Containment Leak-
Test Program'' is also being published for comment. The regulatory
guide endorses an industry standard which contains guidance on an
acceptable performance-based leak-test program, leakage rate test
methods, procedures, and analyses that may be used to implement these
requirements and criteria.
This draft guide is being issued to involve the public in the early
stages of the development of a regulatory position in this area. It has
not received complete staff review and does not represent an official
NRC staff position.
Public comments are being solicited on the draft guide. Comments
should be accompanied by supporting data. Specific comments are
solicited on whether the regulatory guide and the industry guideline it
endorses will result in a common understanding between licensees and
the NRC on how performance will be measured and judged, and can be
objectively inspected against. Written comments may be submitted to the
Rules Review and Directives Branch, Division of Freedom of Information
and Publications Services, Office of Administration, U.S. Nuclear
Regulatory Commission, Washington, DC 20555. Comments will be most
helpful if received by May 8, 1995. Comments on the draft regulatory
guide may be submitted electronically as indicated elsewhere under the
ADDRESSES heading
comments may be submitted to the
Rules Review and Directives Branch, Division of Freedom of Information
and Publications Services, Office of Administration, U.S. Nuclear
Regulatory Commission, Washington, DC 20555. Comments will be most
helpful if received by May 8, 1995. Comments on the draft regulatory
guide may be submitted electronically as indicated elsewhere under the
ADDRESSES heading.
Although a time limit is given for comments on these drafts,
comments and suggestions in connection with (1) items for inclusion in
guides currently being developed or (2) improvements in all published
guides are encouraged at any time.
Regulatory guides are available for inspection at the Commission's
Public Document Room, 2120 L Street NW., Washington, DC. Requests for
single copies of draft guides (which may be reproduced and are
available free to the extent of supply) or for placement on an
automatic distribution list for single copies of future draft guides in
specific divisions should be made in writing to the
Office of Administration, Printing and Mail Services Section, U.S.
Nuclear Regulatory Commission, Washington, DC 20555-0001. Telephone
requests cannot be accommodated. Regulatory guides are not copyrighted,
and Commission approval is not required to reproduce them. The draft
regulatory guide may also be viewed and downloaded electronically via
the Electronic Bulletin Board established by NRC for this rulemaking.

Implementation
nd Mail Services Section, U.S.
Nuclear Regulatory Commission, Washington, DC 20555-0001. Telephone
requests cannot be accommodated. Regulatory guides are not copyrighted,
and Commission approval is not required to reproduce them. The draft
regulatory guide may also be viewed and downloaded electronically via
the Electronic Bulletin Board established by NRC for this rulemaking.

Implementation

The proposed Option B to Appendix J specifies that the rule will
become effective 30 days after publication. At any time thereafter, a
licensee or applicant would notify the NRC of its desire to perform
containment leakage rate testing according to Option B. Accompanying
this notification, a licensee would submit proposed technical
specifications changes which would eliminate those technical
specifications which implement the current rule and propose a new
technical specification referencing the NRC regulatory guide or, if the
licensee desires, an alternative implementation guidance.
Implementation must await staff review and approval of the licensee's
proposal. The staff anticipates that a generic communication will be
issued which will provide the implementation procedure to all power
reactor licensees.

Solicitation of Comments for Future Revisions

As indicated earlier in this notice, the NRC plans a second phase
of modifications to requirements for containment leakage rate testing
to further adopt risk-based methods, and to broadly examine the type of
performance-based rule needed to ensure the adequacy of the containment
function. This will include increasing the allowable leakage rate based
on risk considerations, further examination of the risk significance of
various attributes of containment performance (structural and leaktight
integrity of containment structures and components, and inadvertent
bypass), and consideration of the potential of on-line monitoring of
containment integrity to address certain attributes
This will include increasing the allowable leakage rate based
on risk considerations, further examination of the risk significance of
various attributes of containment performance (structural and leaktight
integrity of containment structures and components, and inadvertent
bypass), and consideration of the potential of on-line monitoring of
containment integrity to address certain attributes. In order to guide
this future effort, the NRC has formulated the following questions and
solicits public comments on them:
1. Should NRC pursue a fundamental modification of its regulations
in this area by establishing an allowable leakage rate based on risk
analysis (as presented in draft NUREG-1493, Chapter 5), as compared to
the current practice of using deterministic design basis accidents and
dose guidelines contained in 10 CFR part 100; or should the NRC modify
the allowable leakage rate within the current licensing basis by
revising source terms and updating regulatory guides (R.G.s 1.3 and
1.4)6 for calculating doses to the public? What are the advantages
and disadvantages of the two approaches? What are some other
considerations than risk to public, e.g. plant control room
habitability, that might limit the allowable leakage rate?

\6\Copies may be purchased at current rates from the
Superintendent of Documents, U. S. Government Printing Office, Mail
Stop SSOP, Washington, DC 20402-9328 (telephone 202 512-2249 or 202
512-2171); or from the National Technical Information Service by
writing NTIS at Port Royal Road, Springfield, VA 22161.
---------------------------------------------------------------------------
ge rate?

\6\Copies may be purchased at current rates from the
Superintendent of Documents, U. S. Government Printing Office, Mail
Stop SSOP, Washington, DC 20402-9328 (telephone 202 512-2249 or 202
512-2171); or from the National Technical Information Service by
writing NTIS at Port Royal Road, Springfield, VA 22161.
---------------------------------------------------------------------------

2. If the allowable leakage rate is increased, could on-line
monitoring of containment integrity replace other current containment
tests? Could the results of the on-line monitoring be used to establish
a new performance basis for containment integrity involving less
stringent reporting requirements if there is high assurance there are
no large leakage paths in containment (> 1 in. diameter).
3. Are there any other regulatory approaches and technical methods
by which the NRC can adopt a complete performance and risk basis to its
regulations for containment leaktight integrity? What are some of the
attributes for performance, and what risk-based methods can be used to
analyze these attributes?

Finding of No Significant Environmental Impact: Availability

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. There will be no radiological environmental impact offsite,
and the occupational exposure onsite is expected to decrease by about
0.8 person rem per year of plant operation for plant personnel if
licensees adopt the performance-based testing scheme provided in the
revised regulation. Alternatives to issuing this revision of the
regulation were considered and found not acceptable
ot
required. There will be no radiological environmental impact offsite,
and the occupational exposure onsite is expected to decrease by about
0.8 person rem per year of plant operation for plant personnel if
licensees adopt the performance-based testing scheme provided in the
revised regulation. Alternatives to issuing this revision of the
regulation were considered and found not acceptable. Single copies of
the environmental assessment and finding of no significant impact can
be obtained by submitting a written request to: Dr. Moni Dey, U.S.
Nuclear Regulatory Commission, Washington, DC 20555.

Paperwork Reduction Act Statement

This proposed rule amends information collection requirements that
are subject to the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et
seq.). This rule has been submitted to the Office of Management and
Budget for review and approval of the paperwork requirements.
Because the rule will relax existing information collection
requirements by providing an option to the existing requirements, the
public burden for this collection of information is expected to be
reduced by as much as 4583 hours per year, including the time required
for reviewing instructions, searching existing data sources, gathering
and maintaining the data needed and completing and reviewing the
collection of information. Send comments regarding the estimated burden
reduction or any other aspect of this collection of information to the
Information and Records Management Branch, T-6F33, U.S. Nuclear
Regulatory Commission, Washington, DC 20555-0001; and to the Desk
Officer, Office of Information and Regulatory Affairs, NEOB-10202,
(3150-0011), Office of Management and Budget, Washington, DC 20503.
Regulatory Analysis
comments regarding the estimated burden
reduction or any other aspect of this collection of information to the
Information and Records Management Branch, T-6F33, U.S. Nuclear
Regulatory Commission, Washington, DC 20555-0001; and to the Desk
Officer, Office of Information and Regulatory Affairs, NEOB-10202,
(3150-0011), Office of Management and Budget, Washington, DC 20503.
Regulatory Analysis

The Commission has prepared a draft regulatory analysis on this
proposed regulation. The analysis examines the costs and benefits of
the alternatives considered by the Commission. The draft analysis is
available for inspection or copying for a fee in the NRC Public
Document Room, 2120 L Street NW (Lower Level), Washington, DC; the
PDR's mailing address is Mail Stop LL-6, Washington, DC 20555; phone
(202) 634-3273; fax (202) 634-3343.
The Commission requests public comment on the draft 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 rule will not, if
promulgated, have a significant economic impact on a substantial number
of small entities. This proposed rule affects only the licensing and
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 Small Business Size
Standards set out in regulations issued by the Small
Business Administration in 13 CFR part 121.

Backfit Analysis

This proposed revision to a current regulation by the inclusion of
an option that may be voluntarily adopted by licensees, and which
relaxes current requirements, is not considered a backfit under 10 CFR
50.109(a). Therefore, a backfit analysis is not necessary.

List of Subjects in 10 CFR Part 50
n regulations issued by the Small
Business Administration in 13 CFR part 121.

Backfit Analysis

This proposed revision to a current regulation by the inclusion of
an option that may be voluntarily adopted by licensees, and which
relaxes current requirements, is not considered a backfit under 10 CFR
50.109(a). Therefore, a backfit analysis is not necessary.

List of Subjects in 10 CFR Part 50

Antitrust, Classified information, Criminal penalties, Fire
protection, Incorporation by reference, Intergovernmental relations,
Nuclear power plants 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 is revised 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. 1244, 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, as amended by Pub. L. 102-486, sec. 2902, 106 Stat. 3123, (42
U.S.C. 5851). Sections 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)
.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, 68 Stat. 955 (42 U.S.C. 2237).

2. Appendix J to 10 CFR Part 50 is amended by adding the following
language between the heading and the Table of Contents and adding the
language for Option B after Section V.B3.

Appendix J--Primary Reactor Containment Leakage Testing for Water-
Cooled Power Reactors.

This appendix includes two options, A and B, either of which can
be chosen for meeting the requirements of this appendix.

Options A--Prescriptive Requirements

* * * * *
Option B--Performance-Based Requirements

Table of Contents

I. Introduction.
II. Definitions.
III. Performance-based leakage test requirements.
A. Type A test.
B. Type B and C tests.
IV. Recordkeeping.
V. Implementation.

I. Introduction
x includes two options, A and B, either of which can
be chosen for meeting the requirements of this appendix.

Options A--Prescriptive Requirements

* * * * *
Option B--Performance-Based Requirements

Table of Contents

I. Introduction.
II. Definitions.
III. Performance-based leakage test requirements.
A. Type A test.
B. Type B and C tests.
IV. Recordkeeping.
V. Implementation.

I. Introduction

One of the conditions required of all operating licenses for
light-water-cooled power reactors as specified in Sec. 50.54(o) is
that primary reactor containments meet the leakage rate test
requirements in either Option A or B of this appendix. These test
requirements ensure that (a) leakage through these containments or
systems and components penetrating these containments does not
exceed allowable leakage rates specified in the Technical
Specifications and (b) integrity of the containment structure is
maintained during its service life. Option B of this appendix
identifies the performance-based requirements and acceptance
criteria for preoperational and subsequent periodic leakage rate
testing.7

\7\Specific guidance concerning a performance-based leak test
program, acceptable leakage rate test methods, procedures, and
analyses that may be used to implement these requirements and
criteria are provided in draft Regulatory Guide DG-1037,
``Performance-Based Containment System Leakage Testing.''
---------------------------------------------------------------------------

II. Definitions
\7\Specific guidance concerning a performance-based leak test
program, acceptable leakage rate test methods, procedures, and
analyses that may be used to implement these requirements and
criteria are provided in draft Regulatory Guide DG-1037,
``Performance-Based Containment System Leakage Testing.''
---------------------------------------------------------------------------

II. Definitions

Acceptance criteria means the performance standards against
which test results are to be compared for establishing the
acceptability of the containment system as a leakage limiting
boundary.
Containment system means the principal barrier, after the
reactor coolant pressure boundary, to prevent the release of
quantities of radioactive material that would have a significant
radiological effect on the health of the public.
Overall integrated leakage rate means the total leakage rate
through all tested leakage paths, including containment welds,
valves, fittings, and components that penetrate the containment
system.
La (percent/24 hours) means the maximum allowable leakage rate
at pressure Pa as specified in the Technical Specifications.
Pa (p.s.i.g) means the calculated peak containment internal
pressure related to the design basis loss-of-coolant accident as
specified in the Technical Specifications.

III. Performance-Based Leakage Test Requirements

A. Type A Test

Type A tests to measure the containment system overall
integrated leakage rate must be conducted under conditions
representing design basis loss-of-coolant accident containment peak
pressure. A Type A test must be conducted (1) after the containment
system has been completed and is ready for operation and (2) at a
periodic interval based on the historical performance of the overall
containment system as a barrier to fission product releases to
reduce the risk from reactor accidents
cted under conditions
representing design basis loss-of-coolant accident containment peak
pressure. A Type A test must be conducted (1) after the containment
system has been completed and is ready for operation and (2) at a
periodic interval based on the historical performance of the overall
containment system as a barrier to fission product releases to
reduce the risk from reactor accidents. A general visual inspection
of the accessible interior and exterior surfaces of the containment
system for structural deterioration which may affect the containment
leaktight integrity must be conducted prior to each test, and at a
periodic interval between tests based on the performance of the
containment system. The leakage rate must not exceed the allowable
leakage rate (La) with margin as specified in the Technical
Specifications. The test results must be compared with previous
results to examine the performance history of the overall
containment system to limit leakage.

B. Type B and C Tests

Type B pneumatic tests to detect and measure local leakage rates
across pressure retaining, leakage limiting boundaries, and Type C
pneumatic tests to measure containment isolation valve leakage
rates, must be conducted (a) prior to initial criticality, and (b)
periodically thereafter at intervals based on the safety
significance and historical performance of each boundary and
isolation valve to ensure the integrity of the overall containment
system as a barrier to fission product release to reduce the risk
from reactor accidents. The performance-based testing program must
contain performance goals and acceptance criteria, consideration of
factors that affect performance when establishing test intervals,
evaluations of performance of containment system components, and
comparison to previous test results to examine the performance
history of the overall containment system to limit leakage
e risk
from reactor accidents. The performance-based testing program must
contain performance goals and acceptance criteria, consideration of
factors that affect performance when establishing test intervals,
evaluations of performance of containment system components, and
comparison to previous test results to examine the performance
history of the overall containment system to limit leakage. The
tests must demonstrate that (1) the sum of the leakage rates at
accident pressure of Type B tests, and pathway leakage rates from
Type C tests, is less than the total allowable leakage rate (La)
specified in the Technical Specification with margin; and (2) the
performance goal for the reliability of the overall containment
system to limit leakage during reactor accidents is not exceeded.

IV. Recordkeeping

The results of the preoperational and periodic Type A, B, and C
tests must be documented to show that acceptance criteria for
leakage have been met. The comparison to previous results of the
performance of the overall containment system and of individual
components within it must be documented to show that the test
intervals established for the containment system and components
within it are adequate. These records must be available for
inspection at plant sites.
If any Type A, B, or C tests fail to meet their leakage rate
acceptance criteria as defined in the plant Technical
Specifications those failures must be assessed for Emergency
Notification System reporting under Secs. 50.72(b)(1)(ii) and
50.72(b)(2)(i), and for a Licensee Event Report under
Secs. 50.73(a)(2)(ii).
V. Implementation

A. Applicability
e available for
inspection at plant sites.
If any Type A, B, or C tests fail to meet their leakage rate
acceptance criteria as defined in the plant Technical
Specifications those failures must be assessed for Emergency
Notification System reporting under Secs. 50.72(b)(1)(ii) and
50.72(b)(2)(i), and for a Licensee Event Report under
Secs. 50.73(a)(2)(ii).
V. Implementation

A. Applicability

The requirements in either or both Option B, III.A for Type A
tests, and Option B, III.B for Type B and C tests, may be adopted on
a voluntary basis by an operating nuclear power reactor licensee as
specified in Sec. 50.54 in substitution of the requirements for
those tests contained in Option A of this appendix. If the
requirements for tests in Option B, III.A or Option B, III.B are
implemented, the recordkeeping requirements in Option B, IV for
these tests must be substituted for the reporting requirements of
these tests contained in Option A of this appendix.

B. Effective Date

1. Specific exemptions to Option A of this appendix that have
been formally approved by the AEC or NRC, according to 10 CFR 50.12,
are still applicable to Option B of this appendix if necessary,
unless specifically revoked by the NRC.
2. This amendment to this appendix, by inclusion of an
additional option for meeting the requirements of the appendix, is
effective (30 days after the publication of the final rule). At any
time hereafter a licensee or applicant for an operating license can
adopt Option B, or parts thereof, as specified in Section V.A of
this appendix, by submitting a notification of its implementation
plan and request for revision to technical specifications to the
Director of the Office of Nuclear Reactor Regulation.
The regulatory guide or other implementation document used by a
licensee, or applicant for an operating license, to develop a
performance-based leakage testing program must be included, by
general reference, in the plant's technical specifications
ation of its implementation
plan and request for revision to technical specifications to the
Director of the Office of Nuclear Reactor Regulation.
The regulatory guide or other implementation document used by a
licensee, or applicant for an operating license, to develop a
performance-based leakage testing program must be included, by
general reference, in the plant's technical specifications. The
detailed licensee programs must be available at the plant site for
inspection thereafter. The programs must contain justification,
including supporting analyses, if they deviate from methods approved
by the Commission and endorsed in a regulatory guide. The deviations
and their justifications must be described in the notification
provided by the licensee of its implementation plan and the
submittal for revision of plant technical specifications.

Dated at Rockville, MD, this 14th day of February, 1995.

For the Nuclear Regulatory Commission.
John C. Hoyle,
Acting Secretary of the Commission.
[FR Doc. 95-4167 Filed 2-17-95; 8:45 am]
BILLING CODE 7590-01-P

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/FR_PRORULE_95-4167. Check the current official text before relying on it. Not legal advice.