[Federal Register Volume 62, Number 173 (Monday, September 8, 1997)]
[Rules and Regulations]
[Pages 47268-47271]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-23611]



[[Page 47267]]

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Part IV





Nuclear Regulatory Commission





_______________________________________________________________________



10 CFR Part 50



Definition of Safety-Related Structures, Systems, and Components; 
Technical Amendments; Final Rule and Proposed Rule

  Federal Register / Vol. 62, No. 173 / Monday, September 8, 1997 / 
Rules and Regulations  

[[Page 47268]]



NUCLEAR REGULATORY COMMISSION

10 CFR Part 50

RIN 3150-AF75


Definition of Safety-Related Structures, Systems, and Components; 
Technical Amendment

AGENCY: Nuclear Regulatory Commission.

ACTION: Direct final rule.

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SUMMARY: The Nuclear Regulatory Commission is amending its regulations 
to correct an error in the language of several sections in the 
regulations governing nuclear power plant licensing that define the 
term, ``safety-related structures, systems, and components.'' These 
definitions are inconsistent with the definition in regulations 
applicable to the siting of nuclear power plants and the Commission's 
longstanding practice and interpretation of that term.

EFFECTIVE DATE: This direct final rule is effective November 7, 1997, 
unless significant adverse comments are received by October 8, 1997. If 
significant adverse comments are received, the effective date will be 
delayed and timely notice will be published in the Federal Register.

ADDRESSES: Mail comments to: Secretary, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, Attention: Rulemakings and 
Adjudications Staff. Hand deliver comments to 11555 Rockville Pike, 
Maryland, between 7:30 am and 4:15 pm on Federal workdays.
    For information on submitting comments electronically, see the 
discussion under Electronic Access in the Supplementary Information 
Section.
    Copies of any comments received may be examined at the NRC Public 
Document Room, 2120 L Street NW (Lower Level), Washington, DC.

FOR FURTHER INFORMATION CONTACT: Geary S. Mizuno, Office of General 
Counsel, U.S. Nuclear Regulatory Commission, Washington DC 20555-0001, 
telephone (301) 415-1639,; e-mail [email protected], or Clark Prichard, 
Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, telephone (301) 415-6203; e-mail 
[email protected].

SUPPLEMENTARY INFORMATION: This direct final rule corrects an error in 
the language of several regulations in 10 CFR Part 50 defining the 
term, ``safety-related structures, systems, and components,'' which is 
inconsistent with the concept of ``safety-related structures, systems, 
and components'' in 10 CFR Part 100, Appendix A.
    Currently, ``safety-related structures, systems, and components'' 
in 10 CFR 50.2 (Definitions) and 10 CFR 50.65 (Maintenance Rule), and 
``safety-related electrical equipment'' in 10 CFR 50.49 (Environmental 
Qualifications Rule) are defined as those structures, systems and 
components that are relied upon to remain functional during and 
following design basis events to ensure:
    (1) The integrity of the reactor coolant pressure boundary,
    (2) The capability to shut down the reactor and maintain it in a 
safe shutdown condition, and
    (3) The capability to prevent or mitigate the consequences of 
accidents which could result in potential offsite exposures comparable 
to the applicable guideline exposures set forth in Sec. 50.34(a)(1) or 
Sec. 100.11 of this chapter, as applicable. (emphasis added)
    The corrections would replace the conjunctive word, ``and,'' by the 
disjunctive word, ``or,'' in these regulations, thereby clarifying that 
a structure, system, or component which falls into any one (or more) of 
the three categories set forth in the definition shall be regarded as 
``safety-related.'' The correction would also delete the word, 
``postulated,'' in the definition of safety-related structures, 
systems, and components' in 10 CFR 50.2. The corrections do not 
constitute a change in Commission policy with respect to the scope of 
structures, systems, and components to be regarded as ``safety-
related.'' Rather, the corrections will conform the language in 10 CFR 
50.2, 50.49 and 50.65 to the language in 10 CFR Part 100, Appendix A, 
where the concept of ``safety-related structures, systems and 
components'' was first incorporated into the Commission's regulations.
    In 10 CFR Part 100, Appendix A, which sets forth the seismic design 
requirements for nuclear power plants, the nuclear power plant 
applicant must determine the design basis for vibratory ground motion 
from the ``Safe Shutdown Earthquake'' (SSE). Once the SSE is 
determined, the nuclear power plant must be designed such that ``if a 
Safe Shutdown Earthquake occurs, certain structures, systems and 
components will remain functional.'' Id., Subparagraph VI.(a)(1). The 
regulation then defines these structures, systems and components which 
must be designed to withstand the SSE as those necessary to assure:
    (i) The integrity of the reactor coolant pressure boundary,
    (ii) The capability to shut down the reactor and maintain it in a 
safe shutdown condition, or
    (iii) The capability to prevent or mitigate the consequences of 
accidents which could result in potential offsite exposures comparable 
to the guideline exposures of this part.'' (emphasis added).
    Id., see also 10 CFR Part 100, Appendix A, Section III, definition 
of ``safe shutdown earthquake.'' The regulation then denotes these 
structures, systems and components as ``safety-related.'' 10 CFR Part 
100, Appendix A, Subparagraph VI.(a)(1)(second textual 
paragraph).1
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    \1\ See also 38 FR 31279 at 31280 (November 13, 1973) (middle 
column) noting that Paragraph VI(a)(1) of the final rule was changed 
to ``eliminate the requirement that safety-related structures, 
systems, and components also be designed to withstand the effects of 
vibratory motion of fifty percent of the Safe Shutdown Earthquake in 
combination with other appropriate loads well within elastic 
limits.'' (emphasis added).
---------------------------------------------------------------------------

    The first regulation in 10 CFR Part 50 utilizing the term, 
``safety-related'' was 10 CFR Part 50, Appendix B, the introduction of 
which stated that the requirements of the appendix applied to the 
``safety-related functions'' of structures, systems, and components 
which prevent or mitigate the consequences of postulated accidents. 
However, Appendix B did not actually include a definition of ``safety-
related''. The first regulation in 10 CFR Part 50 to include a 
definition of ``safety-related structures, systems, and components'' 
was 10 CFR 50.49. As originally promulgated, Sec. 50.49((b)(1) defined 
``safety-related equipment'' as those necessary ``to ensure:
    (i) The integrity of the reactor coolant pressure boundary,
    (ii) The capability to shut down the reactor and maintain it in a 
safe condition, and
    (iii) The capability to prevent or mitigate the consequences of 
accidents which could result in potential offsite exposures comparable 
to the 10 CFR Part 100 guidelines.'' (emphasis added) (48 FR 2729; 
January 21, 1983).
    Thus, the core definition of ``safety-related equipment'' in 10 CFR 
50.49 was essentially the same as the definition of ``safety-related 
structures, systems, and components'' in 10 CFR Part 100, Appendix A. 
However, nothing in the statements of considerations for the proposed 
or final 10 CFR 50.49 explains why the ``or'' in the core definition of 
``safety related'' was changed to ``and.'' See 47 FR 2876; January 20, 
1982--proposed rule and 48 FR 2729; January 21, 1983--final rule. Nor 
was there any discussion in the statements of

[[Page 47269]]

considerations which would suggest that the Commission intended to 
narrow the scope of structures, systems and components that would be 
considered ``safety-related.'' Indeed, language in Revision 1 to 
Regulatory Guide (RG) 1.89, ``Environmental Qualification of Certain 
Electrical Equipment Important to Safety for Nuclear Power Plants'' 
(June 1984) strongly suggests that the use of the conjunctive word, 
``and'' was an error and was not intended to change the fundamental 
scope of safety-related structures, systems and components. Appendix A 
to RG 1.89, ``Typical Safety-Related Electrical Equipment or System,'' 
purports to list systems and equipment that are ``safety-related.'' 
However, none of the equipment and systems actually listed as being 
``safety-related'' would meet the definition of safety-related 
structures, systems and components if the conjunctive ``and'' were 
interpreted to require all three criteria in the ``safety-related'' 
definition to be satisfied. Moreover, a footnote to Appendix A of RG 
1.89 states:

    Paragraph 50.49(b)(1) identifies safety-related electrical 
equipment as a subset of electrical equipment important to safety 
and defines it as the equipment that is relied upon to remain 
functional during and following design basis events to ensure (1) 
the integrity of the reactor coolant pressure boundary, (2) the 
capability to shut down the reactor and maintain it in a safe 
condition, or (3) the capability to prevent or mitigate the 
consequences of accidents which could result in potential offsite 
exposures comparable to the 10 CFR Part 100 guidelines. (emphasis 
added)

    That the RG uses the disjunctive ``or'' when describing the 
underlying regulatory requirement of 10 CFR 50.49 is a strong 
indication that the NRC did not intend to change the scope of 
structures, systems, and components deemed to be ``safety-related,'' 
and that the use of the conjunctive word, ``and,'' was a grammatical 
error.
    The conjunctive word, ``and,'' was subsequently used in the 
Maintenance Rule, 10 CFR 50.65, to describe the structures, systems, 
and components subject to the rule, as well as in the definition of 
``safety-related structures, systems, and components'' contained in 10 
CFR 50.2, which was added by a 1996 rulemaking amending Parts 50 and 
100. Because the statements of considerations for the proposed and 
final rules did not contain any discussion of the ``safety-related'' 
definition, the Commission concludes that the subsequent rules simply 
repeated the definition used in 10 CFR 50.49 without intending any 
change in the scope of safety-related structures, systems, and 
components. See 53 FR 47822 (November 28, 1988--proposed Maintenance 
Rule); 56 FR 31324 (July 10, 1991--final Maintenance Rule); 57 FR 47802 
(October 20, 1992--first proposed rule amending parts 50 and 100); 59 
FR 52255 (October 17, 1994--second proposed rule amending parts 50 and 
100); and 61 FR 65171 (December 11, 1996--final rule amending parts 50 
and 100).
    The final rule amending 10 CFR Parts 50 and 100, which inter alia 
added the definition of ``safety-related structures, systems, and 
components to 10 CFR 50.2, also added the word, ``postulated,'' to the 
term, ``design basis events,'' so that the term reads, ``design basis 
(postulated) events.'' Nothing in the statements of consideration for 
the first or second proposed rules, or the final rule, explains the 
addition of the word, ``postulated,'' in the Section 50.2 definition of 
``safety-related structures, systems, and components while leaving it 
out of the definitions of ``safety-related structures, systems, and 
components'' in 10 CFR 50.65 and 10 CFR Part 100, Appendix A, and 
``safety-related electrical equipment'' in 10 CFR 50.49. Therefore, the 
Commission also concludes that the addition of the word, ``postulated'' 
was an error and should be removed to conform the definition of 
``safety-related structures, systems, and components'' to the long-
standing wording of that term.
    For these reasons, the Commission has determined that the 
amendments to 10 CFR 50.2, 50.49, and 50.65 are of a corrective nature, 
and do not involve any change in existing policy or otherwise 
constitute a new policy with respect to the scope of structures, 
systems, and components considered to be ``safety-related.'' 
Furthermore, since these amendments clarify the original intent of the 
Commission, they can be considered to be an interpretation of existing 
regulations. Accordingly, the Commission finds that public notice and 
opportunity for comment are unnecessary pursuant to 10 U.S.C. 
553(b)(3)(A) and (B), and the Commission is publishing this rule in 
final form without first seeking public comments on the amendment in a 
proposed rule. However, if the NRC receives significant adverse comment 
by [30 days after publication], the NRC will publish a notice in the 
Federal Register that withdraws this action, and will address the 
comments received in response to this direct final rule as comments on 
a proposed rule (identical to this direct final rule) that is being 
concurrently published in the proposed rules section of this Federal 
Register. Any significant adverse comments will be deemed to be 
comments on the proposed rule and will be addressed in a subsequent 
final rule. The NRC will not initiate a second comment period on this 
action.

Criminal Penalties

    For purposes of Section 223 of the Atomic Energy Act of 1954, as 
amended (AEA), the Commission is issuing the direct final rule under 
one or more of sections 161b, 161i, or 161o of the AEA. Willful 
violations of the direct final rule are subject to criminal 
enforcement.

Electronic Access

    Comments may be submitted electronically, in either ASCII text or 
Word Perfect format (version 5.1), by calling the NRC Electronic 
Bulletin Board on FedWorld or connecting to the NRC interactive 
rulemaking web site, ``Rulemaking Forum.'' 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. Communications 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: 703-321-3339; 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, access the NRC subsystem from the main FedWorld menu by 
selecting ``F--Regulatory, Government Administration and State 
Systems,'' then selecting ``A--Regulatory Information Mall.'' At that 
point, a menu will be displayed that has

[[Page 47270]]

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.
    If you contact FedWorld using Telnet, you will see the NRC area and 
menus, including the Rules menu. Although you will be able to download 
documents and leave messages, you will not be able to write comments or 
upload files (comments). If you contact FedWorld using FTP, all files 
can be accessed and downloaded but uploads are not allowed; all you 
will see is a list of files without descriptions (normal Gopher look). 
An index file listing all files within a subdirectory, with 
descriptions, is included. There is a 15-minute time limit for FTP 
access.
    Although FedWorld can be accessed through the World Wide Web, like 
FTP that mode only provides access for downloading files and does not 
display the NRC Rules menu.
    You may also access the NRC's interactive rulemaking web site 
through the NRC home page (http://www.nrc.gov). This site provides the 
same access as the FedWorld bulletin board, including the facility to 
upload comments as files (any format), if your web browser supports 
that function.
    For more information on NRC bulletin boards, call Mr. Arthur Davis, 
Systems Integration and Development Branch, U.S. Nuclear Regulatory 
Commission, Telephone: 301-415-5780; e-mail: AXD[email protected]. For 
information about the interactive rulemaking site, contact Ms. Carol 
Gallagher, (301) 415-6215; e-mail [email protected].

Environmental Impact: Categorical Exclusion

    The Commission has determined that this direct final rule is the 
type of action described in categorical exclusion 10 CFR 51.22(c)(2), 
since this direct final rule makes amendments to the regulations which 
are corrective and nonpolicy in nature. Therefore, neither an 
environmental impact statement nor an environmental assessment has been 
prepared for this final rule.

Paperwork Reduction Act Statement

    This direct final rule does not contain a new or significantly 
amended information collection requirement subject to the Paperwork 
Reduction Act of 1995 (44 U.S.C. 3501, et seq.). Existing requirements 
were approved by the Office of Management and Budget, approval number 
3150-0011.

Public Protection Notification

    The NRC may not conduct or sponsor, and a person is not required to 
respond to, a collection of information unless it displays a currently 
valid OMB control number.

Regulatory Analysis

    The Commission has not prepared a regulatory analysis for this 
action because this direct final rule does not present new or revised 
positions, impose a new requirement, or recommend new action.

Regulatory Flexibility Certification

    As required by the Regulatory Flexibility Act of 1980 (5 U.S.C. 
605(b)), the Commission certifies that this rule will not have a 
significant economic impact on small entities. This rule affects only 
the operation of nuclear power plants. The companies that own these 
plants do not fall within the scope of the definition of ``small 
entities'' set forth in the Regulatory Flexibility Act or the small 
business size standards adopted by the NRC (10 CFR 2.810). Since these 
companies are dominant in their service areas, this rule does not fall 
within the purview of the Act.

Backfit Analysis

    The direct final rule does not impose any change on licensees with 
respect to the term, ``safety-related structures, systems and 
components.'' Rather, it provides a definition of ``safety-related 
structures, systems and components'' throughout 10 CFR Part 50 that is 
identical to the definition contained in 10 CFR Part 100, Appendix A, 
the NRC's first regulation defining ``safety-related structures, 
systems and components,'' which provides that ``safety-related'' 
structures, systems and components are those that possess any one of 
the three numbered attributes listed in the definition. This definition 
is consistent with both the NRC's and nuclear power plant licensees' 
longstanding understanding that the term, ``safety-related structures, 
systems and components'' includes those structures, systems and 
components that possess any one of the three listed attributes. 
Therefore, the NRC has determined that the Backfit Rule, 10 CFR 50.109, 
does not apply to this direct final rule because it does not impose any 
backfits as defined in 10 CFR 50.109(a)(1), and a backfit analysis has 
not been prepared for this direct final rule.

Small Business Regulatory Enforcement Fairness Act

    In accordance with the Small Business Regulatory Enforcement 
Fairness Act of 1996, the NRC has determined that this action is not a 
``major rule'' and has verified this determination with the Office of 
Information and Regulatory Affairs, Office of Management and Budget.

List of Subjects in 10 CFR Part 50

    Antitrust, Classified information, Criminal penalties, Fire 
protection, 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. 552 and 553, the NRC is adopting 
the following amendments to 10 CFR Part 50.

PART 50--DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION 
FACILITIES

    1. The authority citation for Part 50 continues to read as follows:

    Authority: Secs. 102, 103, 104, 105, 161, 182, 183, 186, 189, 68 
Stat. 936, 937, 938, 948, 953, 954, 955, 956, as amended, sec. 234, 
83 Stat. 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 (42 U.S.C. 5851). Section 50.10 also issued under secs. 101, 
185, 68 Stat. 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, and 
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. In Sec. 50.2, the definition of safety-related structures, 
systems and components is revised to read as follows:

[[Page 47271]]

Sec. 50.2  Definitions.

* * * * *
    Safety-related structures, systems and components means those 
structures, systems and components that are relied upon to remain 
functional during and following design basis events to assure:
    (1) The integrity of the reactor coolant pressure boundary
    (2) The capability to shut down the reactor and maintain it in a 
safe shutdown condition; or
    (3) The capability to prevent or mitigate the consequences of 
accidents which could result in potential offsite exposures comparable 
to the applicable guideline exposures set forth in Sec. 50.34(a)(1) or 
Sec. 100.11 of this chapter, as applicable.
* * * * *
    3. In Sec. 50.49, paragraph (b)(1)(i)(B) is revised to read as 
follows:


Sec. 50.49  Environmental qualification of electric equipment important 
to safety for nuclear power plants.

* * * * *
    (b) * * *
    (1) * * *
    (i) * * *
    (B) The capability to shut down the reactor and maintain it in a 
safe shutdown condition; or
* * * * *
    4. In Sec. 50.65, paragraph (b)(1) is revised to read as follows:


Sec. 50.65  Requirements for monitoring the effectiveness of 
maintenance at nuclear power plants.

* * * * *
    (b) * * *
    (1) Safety-related structures, systems and components that are 
relied upon to remain functional during and following design basis 
events to ensure the integrity of the reactor coolant pressure 
boundary, the capability to shut down the reactor and maintain it in a 
safe shutdown condition, or the capability to prevent or mitigate the 
consequences of accidents that could result in potential offsite 
exposure comparable to the guidelines in Sec. 50.34(a)(1) or 
Sec. 100.11 of this chapter, as applicable.
* * * * *
    Dated at Rockville, MD, this 5th day of August, 1997.

    For the Nuclear Regulatory Commission.
L. Joseph Callan,
Executive Director for Operations.
[FR Doc. 97-23611 Filed 9-5-97; 8:45 am]
BILLING CODE 7590-01-P