82 FR 28017 - Decoupling an Assumed Loss of Offsite Power From a Loss-of-Coolant Accident

NUCLEAR REGULATORY COMMISSION

Federal Register Volume 82, Issue 117 (June 20, 2017)

Page Range		28017-28020
FR Document		2017-12792
The U.S. Nuclear Regulatory Commission (NRC) is discontinuing the rulemaking activity, ``Decoupling an Assumed Loss of Offsite Power from a Loss-of-Coolant Accident'' (the LOOP/LOCA rulemaking), and denying the associated petition for rulemaking (PRM), PRM-50-77. The purpose of this action is to inform members of the public of the discontinuation of the rulemaking activity and the denial of the PRM, and to provide a brief discussion of the NRC's decision regarding the rulemaking activity and PRM. The rulemaking activity will no longer be reported in the NRC's portion of the Unified Agenda of Regulatory and Deregulatory Actions (the Unified Agenda).
Federal Register, Volume 82 Issue 117 (Tuesday, June 20, 2017)
[Federal Register Volume 82, Number 117 (Tuesday, June 20, 2017)]
[Proposed Rules]
[Pages 28017-28020]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2017-12792]


=======================================================================
-----------------------------------------------------------------------

NUCLEAR REGULATORY COMMISSION

10 CFR Part 50

[NRC-2008-0602, NRC-2002-0020]
RIN 3150-AH43


Decoupling an Assumed Loss of Offsite Power From a Loss-of-
Coolant Accident

AGENCY: Nuclear Regulatory Commission.

ACTION: Discontinuation of rulemaking activity and denial of petition 
for rulemaking.

-----------------------------------------------------------------------

SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is discontinuing 
the rulemaking activity, ``Decoupling an Assumed Loss of Offsite Power 
from a Loss-of-Coolant Accident'' (the LOOP/LOCA rulemaking), and 
denying the associated petition for rulemaking (PRM), PRM-50-77. The 
purpose of this action is to inform members of the public of the 
discontinuation of the rulemaking activity and the denial of the PRM, 
and to provide a brief discussion of the NRC's decision regarding the 
rulemaking activity and PRM. The rulemaking activity will no longer be 
reported in the NRC's portion of the Unified Agenda of Regulatory and 
Deregulatory Actions (the Unified Agenda).

DATES:  Effective June 20, 2017, the rulemaking activity discussed in 
this document is discontinued and PRM-50-77 is denied.

ADDRESSES: Please refer to Docket IDs NRC-2008-0602 (rulemaking 
activity) and NRC-2002-0020 (PRM) when contacting the NRC about the 
availability of information regarding this document. You may obtain 
publicly-available information related to this document using any of 
the following methods:
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket IDs NRC-2008-0602 (rulemaking 
activity) and NRC-2002-0020 (PRM). Address questions about NRC dockets 
to Carol Gallagher; telephone: 301-415-3463; email: 
[email protected]. For technical questions, contact the 
individual listed in the FOR FURTHER INFORMATION CONTACT section of 
this document.
     NRC's Agencywide Documents Access and Management System 
(ADAMS): You may obtain publicly-available documents online in the 
ADAMS Public Documents collection at http://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``ADAMS Public Documents'' and 
then select ``Begin Web-based ADAMS Search.'' For problems with ADAMS, 
please contact the NRC's Public Document Room (PDR) reference staff at 
1-800-397-4209, 301-415-4737, or by email to [email protected]. The 
ADAMS accession number for each document referenced in this document 
(if that document is available in ADAMS) is provided the first time 
that a document is referenced.
     NRC's PDR: You may examine and purchase copies of public 
documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555 
Rockville Pike, Rockville, Maryland 20852.

FOR FURTHER INFORMATION CONTACT: Robert Beall, Office of Nuclear 
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001; telephone: 301-415-3874; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Background

[[Page 28018]]

II. Process for Discontinuing Rulemaking Activities
III. Decoupling an Assumed Loss of Offsite Power From a Loss-of-
Coolant Accident
IV. Petition for Rulemaking (PRM-50-77)
V. Conclusion

I. Background

    In both SECY-01-0133, ``Status Report on Study of Risk-Informed 
Changes to the Technical Requirements of 10 CFR part 50 (Option 3) and 
Recommendations on Risk-Informed Changes to 10 CFR 50.46 (ECCS 
Acceptance Criteria),'' dated July 23, 2001 (ADAMS Accession No. 
ML011800492), and SECY-02-0057, ``Update to SECY-01-0133, 'Fourth 
Status Report on Study of Risk-Informed Changes to the Technical 
Requirements of 10 CFR part 50 (Option 3) and Recommendations on Risk-
Informed Changes to 10 CFR 50.46 (ECCS Acceptance Criteria)' '' (ADAMS 
Accession No. ML020660607), the NRC staff recommended developing a 
possible risk-informed alternative to reliability requirements in Sec.  
50.46 of title 10 of the Code of Federal Regulations (10 CFR) and 
General Design Criterion (GDC) 35, ``Emergency Core Cooling,'' of 
appendix A, ``General Design Criteria for Nuclear Power Plants,'' to 10 
CFR part 50, ``Domestic Licensing of Production and Utilization 
Facilities.'' On March 31, 2003, in the staff requirements memorandum 
(SRM) for SECY-02-0057, the Commission directed the NRC staff to 
proceed with a rulemaking to risk-inform the emergency core cooling 
system (ECCS) functional reliability requirements in GDC 35 (ADAMS 
Accession No. ML030910476). This proposed rulemaking would provide 
licensees an option to relax the current analysis requirements for 
considering a loss of offsite power (LOOP) to occur coincident with a 
large-break loss-of-coolant accident (LOCA) (the LOOP/LOCA rulemaking). 
The SRM also stated that the NRC staff should include relevant issues 
and uncertainties that can impact plant risk (e.g., delayed LOOP and 
``double sequencing'' \1\ of safety functions).
---------------------------------------------------------------------------

    \1\ Double sequencing is defined as a situation where 
electrically powered safety and accident mitigation equipment 
automatically start, shut down, and restart in rapid succession when 
called on to operate. Delayed LOOP and double sequencing were 
evaluated and dispositioned in GSI-171, ``ESF Failure from LOOP 
Subsequent to LOCA,'' for the current regulations (https://www.nrc.gov/sr0933/Section%203.%20New%20Generic%20Issues/171r1.html#). GSI-171 does not need to be reevaluated if the LOOP/
LOCA rulemaking is discontinued.
---------------------------------------------------------------------------

    In parallel with the LOOP/LOCA rulemaking, the NRC pursued a 
separate rulemaking for a risk-informed definition of large-break LOCA 
ECCS analysis requirements (the 50.46a ECCS rulemaking). The proposed 
regulations in the 50.46a ECCS rulemaking would have allowed both 
pressurized water reactors (PWRs) and boiling water reactors (BWRs) to 
decouple a LOOP from a LOCA for certain break sizes.

II. Process for Discontinuing Rulemaking Activities

    When the NRC staff identifies a rulemaking activity that can be 
discontinued, the staff requests approval from the Commission to 
discontinue it in a Commission paper. The Commission provides its 
decision in an SRM. If the Commission approves discontinuing a 
rulemaking activity, the NRC staff informs the public of the 
Commission's decision.
    A rulemaking activity may be discontinued at any stage in the 
rulemaking process. For a rulemaking activity that has received public 
comments, the NRC considers those comments before discontinuing the 
rulemaking activity; however, the NRC staff will not provide individual 
comment responses.
    After Commission approval to discontinue the rulemaking activity, 
the NRC staff updates the next edition of the Unified Agenda to 
indicate that the rulemaking is discontinued. The rulemaking activity 
will appear in the completed section of that edition of the Unified 
Agenda but will not appear in future editions.
    A rulemaking activity proposed for discontinuation may have been 
initiated in response to accepting one or more PRMs, or may include 
issues from one or more PRMs that were accepted and added to the 
ongoing related rulemaking activity. Therefore, discontinuation of the 
rulemaking activity also requires the NRC to take action to resolve the 
associated PRM(s) and to inform the petitioner(s) and the public of the 
NRC's action. The NRC's action to discontinue a rulemaking would 
normally result in NRC denial of the associated PRM for the same 
reasons.

III. Decoupling an Assumed Loss of Offsite Power From a Loss-of-Coolant 
Accident

    The Boiling Water Reactor Owners Group (BWROG) submitted for NRC 
review a licensing topical report NEDO-33148, ``Separation of Loss of 
Offsite Power from Large Break LOCA,'' dated April 27, 2004 (ADAMS 
Accession No. ML041210900). The BWROG stated that the licensing topical 
report would support plant-specific exemption requests to implement 
plant changes that are currently not possible with the existing 
regulatory requirements to consider a LOOP coincident with a large 
break LOCA. The NRC intended to derive some of the technical support 
for the proposed LOOP/LOCA rulemaking from NEDO-33148. The proposed 
rulemaking would allow BWR licensees to make specific design changes 
that otherwise could not be made without exemptions from the current 10 
CFR 50.46 requirements.
    The BWROG initially chose to pursue an approach that relied on a 
generic probabilistic risk assessment (PRA) and other published reports 
for justification of several important assumptions made in NEDO-33148 
(e.g., large-break LOCA probability, consequential/delayed LOOP, and 
double sequencing of electrical loads). The BWROG proposed to address 
these issues in Revision 2 of NEDO-33148, which was submitted on August 
25, 2006 (ADAMS Accession No. ML062480321). Revision 2 presented the 
risk analyses as risk assessment methodologies rather than a generic 
risk assessment. In a letter to the BWROG dated March 24, 2008 (ADAMS 
Accession No. ML080230696), the NRC detailed the conditions and 
limitations that were required for approval of NEDO-33148, Revision 2. 
Some of the outstanding technical issues included LOOP/LOCA frequency 
determinations, seismic contributions to break frequency, the 
maintenance of defense-in-depth, and the treatment of delayed LOOP and 
double sequencing issues. The NRC staff determined that these issues 
needed to be adequately addressed in order to complete a regulatory 
basis that could support a proposed LOOP/LOCA rulemaking.
    On June 12, 2008, the BWROG formally withdrew its licensing topical 
report, NEDO-33148, from further NRC review and discontinued its 
supporting effort. The BWROG's withdrawal letter (ADAMS Accession No. 
ML081680048) stated that further development of NEDO-33148 ``is no 
longer cost effective and, if ultimately approved in the form presently 
desired by NRC staff, adoption by licensees would most likely be 
prohibitively expensive.'' The withdrawal of NEDO-33148 and the 
discontinued effort by the BWROG demonstrated a potential loss of 
industry interest in this initiative.
    In SECY-09-0140, ``Rulemaking Related to Decoupling an Assumed Loss 
of Offsite Power From a Loss-of-Coolant Accident, 10 CFR part 50, 
Appendix A, General Design Criterion 35 (RIN 3150-AH43),'' dated 
September 28, 2009 (ADAMS Accession No. ML092151078), the NRC staff 
proposed three options for the Commission to consider as a path

[[Page 28019]]

forward on the LOOP/LOCA rulemaking: (1) Discontinue the LOOP/LOCA 
rulemaking, (2) proceed with the LOOP/LOCA rulemaking without the BWROG 
topical report, or (3) continue to defer the LOOP/LOCA rulemaking until 
implementation of the 50.46a ECCS rulemaking. The Commission approved 
the third option, to defer the LOOP/LOCA rulemaking, in the SRM for 
SECY-09-0140, dated July 2, 2010 (ADAMS Accession No. ML101830056).
    In SECY-16-0009, ``Recommendations Resulting from the Integrated 
Prioritization and Re-Baselining of Agency Activities,'' dated January 
31, 2016 (ADAMS Accession No. ML16028A189), the NRC staff recommended 
that the 50.46a ECCS rulemaking be discontinued. In the SRM for SECY-
16-0009, dated April 13, 2016 (ADAMS Accession No. ML16104A158), the 
Commission approved discontinuing the 50.46a ECCS rulemaking. A Federal 
Register notice, published on October 6, 2016 (81 FR 69446), informed 
the public of the NRC's decision to discontinue the 50.46a ECCS 
rulemaking.
    In support of the potential risk-informed alternative to 
reliability requirements in 10 CFR 50.46 and GDC 35, the NRC performed 
substantial work in a number of technical areas, including estimating 
LOCA frequencies and the conditional probability of a LOOP, given a 
LOCA (see memorandum from A. Thadani to S. Collins, ``Transmittal of 
Technical Work to Support Possible Rulemaking on a Risk-Informed 
Alternative to 10 CFR 50.46/GDC 35,'' dated July 31, 2002 (ADAMS 
Accession No. ML022120661)). As part of this work, the NRC identified a 
number of areas of uncertainty associated with estimating the 
conditional probability of a LOOP, given occurrence of a LOCA, 
including very limited data on major ECCS actuations and LOOPs after 
such actuations, incomplete knowledge about all of the factors that can 
impact the probability of consequential LOOP because of electrical 
transient factors,\2\ and the impact on offsite system voltage due to 
deregulation of the electric utility industry. To complete a fully 
developed regulatory basis for the LOOP/LOCA rulemaking, the NRC staff 
would need to ensure that these areas of uncertainty are adequately 
addressed as part of the rulemaking activity.
---------------------------------------------------------------------------

    \2\ As used here, transient factors include the electrical 
disturbance triggered by starting electrically powered safety and 
accident mitigation equipment as a result of the LOCA and the 
conditions of the offsite transmission system grid.
---------------------------------------------------------------------------

    On June 28, 2016, and October 26, 2016, the NRC held public 
meetings (ADAMS Accession Nos. ML16203A003 and ML16319A153, 
respectively) to receive external stakeholder feedback on the need for 
a LOOP/LOCA rulemaking. The NRC presented information on what would be 
required by the NRC and the industry to continue the proposed 
rulemaking activity. The NRC's position was similar to the March 24, 
2008, letter to the BWROG detailing the information that would be 
needed to complete review of licensing topical report NEDO-33148. 
Representatives from the Nuclear Energy Institute and the PWR and BWR 
Owners Groups also presented their perspectives on continuing the 
proposed LOOP/LOCA rulemaking effort. The industry re-stated its view 
from the 2008 withdrawal of the licensing topical report that the 
estimated implementation costs would be prohibitively expensive for the 
benefit received. In addition, industry representatives recommended 
that the NRC staff devote its resources to other risk-informed 
licensing activities that have significantly higher industry interest, 
such as applications to implement 10 CFR 50.69, ``Risk-informed 
categorization and treatment of structures, systems and components for 
nuclear power reactors,'' and risk-informed technical specifications.
    The NRC is discontinuing the LOOP/LOCA rulemaking activity. The 
current regulations provide adequate protection of public health and 
safety. This rulemaking would have provided licensees an option to 
relax the current analysis requirements for considering a LOOP to occur 
coincident with a LOCA. Based on the feedback from the industry, it is 
unlikely that any licensee would seek licensing basis changes that 
would rely on the proposed rulemaking. The issues that caused the 
industry to withdraw the BWROG topical report in 2008 are still 
applicable today and the industry has greater interest in the progress 
of other risk-informed initiatives. Therefore, pursuit of this effort 
would likely have minimal practical impact on safety. Based upon (1) 
the assessment that there is no current adequate protection issue with 
respect to compliance with the current ECCS rule, (2) the lack of 
significant safety benefits from the rulemaking, (3) the industry's 
representation that it would be unlikely for any licensee to 
voluntarily use the LOOP/LOCA rule because the estimated implementation 
costs would be prohibitively expensive for the benefit received, and 
(4) the industry's stated interest in pursuing other risk-informed 
licensing activities, the NRC is discontinuing the LOOP/LOCA 
rulemaking.

IV. Petition for Rulemaking (PRM-50-77)

    On May 2, 2002, the NRC received a PRM from Bob Christie, 
Performance Technology (ADAMS Accession No. ML082530041), related to 
the topics in the proposed LOOP/LOCA rulemaking. The PRM requested that 
the NRC amend its regulations in appendix A to 10 CFR part 50 to 
eliminate the requirement to assume a LOOP coincident with postulated 
accidents. The NRC docketed the petition and assigned it Docket No. 
PRM-50-77. The NRC published a notice of receipt and request for 
comment on the PRM on June 13, 2002 (67 FR 40622), and received one 
comment supporting the PRM from the Strategic Teaming and Resource 
Sharing organization (ADAMS Accession No. ML022490192). The petition 
was resolved by a decision to consider its issues within the LOOP/LOCA 
rulemaking, but the petition remained open because of the ongoing 
developments related to this rulemaking. However, in late 2007, the NRC 
Executive Director for Operations approved changes to the PRM process 
to enhance the efficiency and effectiveness of dispositioning a PRM. As 
a result of those enhancements, the NRC closed this petition on April 
13, 2009 (74 FR 16802), with a commitment to follow through with the 
original resolution to consider it within the LOOP/LOCA rulemaking.
    Because of the agency's decision to discontinue the LOOP/LOCA 
rulemaking, the associated petition, PRM-50-77, is denied for the 
reasons discussed above. As provided at Sec.  2.803(i)(2), the NRC has 
decided not to complete the rulemaking action and is documenting this 
denial of the PRM in the docket for the closed PRM.

V. Conclusion

    The NRC is no longer pursuing the LOOP/LOCA rulemaking and is 
denying PRM-50-77 for the reasons discussed in this document. In the 
next edition of the Unified Agenda, the NRC will update the entry for 
the rulemaking activity and reference this document to indicate that 
the rulemaking is no longer being pursued. The rulemaking activity will 
appear in the completed actions section of that edition of the Unified 
Agenda but will not appear in future editions. If the NRC decides to 
pursue a similar or related rulemaking activity in the future, it will 
inform the public through a new rulemaking entry in the Unified Agenda.

    Dated at Rockville, Maryland, this 14th day of June 2017.


[[Page 28020]]


    For the Nuclear Regulatory Commission.
Annette L. Vietti-Cook,
Secretary of the Commission.
[FR Doc. 2017-12792 Filed 6-19-17; 8:45 am]
 BILLING CODE 7590-01-P
28018 Federal Register / Vol. 82, No. 117 / Tuesday, June 20, 2017 / Proposed Rules

II. Process for Discontinuing Rulemaking rulemaking for a risk-informed that are currently not possible with the
Activities definition of large-break LOCA ECCS existing regulatory requirements to
III. Decoupling an Assumed Loss of Offsite analysis requirements (the 50.46a ECCS consider a LOOP coincident with a large
Power From a Loss-of-Coolant Accident
rulemaking). The proposed regulations break LOCA. The NRC intended to
IV. Petition for Rulemaking (PRM–50–77)
V. Conclusion in the 50.46a ECCS rulemaking would derive some of the technical support for
have allowed both pressurized water the proposed LOOP/LOCA rulemaking
I. Background reactors (PWRs) and boiling water from NEDO–33148. The proposed
In both SECY–01–0133, ‘‘Status reactors (BWRs) to decouple a LOOP rulemaking would allow BWR licensees
Report on Study of Risk-Informed from a LOCA for certain break sizes. to make specific design changes that
Changes to the Technical Requirements otherwise could not be made without
II. Process for Discontinuing
of 10 CFR part 50 (Option 3) and exemptions from the current 10 CFR
Rulemaking Activities
Recommendations on Risk-Informed 50.46 requirements.
Changes to 10 CFR 50.46 (ECCS When the NRC staff identifies a The BWROG initially chose to pursue
Acceptance Criteria),’’ dated July 23, rulemaking activity that can be an approach that relied on a generic
2001 (ADAMS Accession No. discontinued, the staff requests approval probabilistic risk assessment (PRA) and
ML011800492), and SECY–02–0057, from the Commission to discontinue it other published reports for justification
‘‘Update to SECY–01–0133, ’Fourth in a Commission paper. The of several important assumptions made
Status Report on Study of Risk-Informed Commission provides its decision in an in NEDO–33148 (e.g., large-break LOCA
Changes to the Technical Requirements SRM. If the Commission approves probability, consequential/delayed
of 10 CFR part 50 (Option 3) and discontinuing a rulemaking activity, the LOOP, and double sequencing of
Recommendations on Risk-Informed NRC staff informs the public of the electrical loads). The BWROG proposed
Changes to 10 CFR 50.46 (ECCS Commission’s decision. to address these issues in Revision 2 of
Acceptance Criteria)’ ’’ (ADAMS A rulemaking activity may be NEDO–33148, which was submitted on
Accession No. ML020660607), the NRC discontinued at any stage in the August 25, 2006 (ADAMS Accession
staff recommended developing a rulemaking process. For a rulemaking No. ML062480321). Revision 2
possible risk-informed alternative to activity that has received public presented the risk analyses as risk
reliability requirements in § 50.46 of comments, the NRC considers those assessment methodologies rather than a
title 10 of the Code of Federal comments before discontinuing the generic risk assessment. In a letter to the
Regulations (10 CFR) and General rulemaking activity; however, the NRC BWROG dated March 24, 2008 (ADAMS
Design Criterion (GDC) 35, ‘‘Emergency staff will not provide individual Accession No. ML080230696), the NRC
Core Cooling,’’ of appendix A, ‘‘General comment responses. detailed the conditions and limitations
Design Criteria for Nuclear Power After Commission approval to that were required for approval of
Plants,’’ to 10 CFR part 50, ‘‘Domestic discontinue the rulemaking activity, the NEDO–33148, Revision 2. Some of the
Licensing of Production and Utilization NRC staff updates the next edition of the outstanding technical issues included
Facilities.’’ On March 31, 2003, in the Unified Agenda to indicate that the LOOP/LOCA frequency determinations,
staff requirements memorandum (SRM) rulemaking is discontinued. The seismic contributions to break
for SECY–02–0057, the Commission rulemaking activity will appear in the frequency, the maintenance of defense-
directed the NRC staff to proceed with completed section of that edition of the in-depth, and the treatment of delayed
a rulemaking to risk-inform the Unified Agenda but will not appear in LOOP and double sequencing issues.
emergency core cooling system (ECCS) future editions. The NRC staff determined that these
functional reliability requirements in A rulemaking activity proposed for issues needed to be adequately
GDC 35 (ADAMS Accession No. discontinuation may have been initiated addressed in order to complete a
ML030910476). This proposed in response to accepting one or more regulatory basis that could support a
rulemaking would provide licensees an PRMs, or may include issues from one proposed LOOP/LOCA rulemaking.
option to relax the current analysis or more PRMs that were accepted and On June 12, 2008, the BWROG
requirements for considering a loss of added to the ongoing related rulemaking formally withdrew its licensing topical
offsite power (LOOP) to occur activity. Therefore, discontinuation of report, NEDO–33148, from further NRC
coincident with a large-break loss-of- the rulemaking activity also requires the review and discontinued its supporting
coolant accident (LOCA) (the LOOP/ NRC to take action to resolve the effort. The BWROG’s withdrawal letter
LOCA rulemaking). The SRM also stated associated PRM(s) and to inform the (ADAMS Accession No. ML081680048)
that the NRC staff should include petitioner(s) and the public of the NRC’s stated that further development of
relevant issues and uncertainties that action. The NRC’s action to discontinue NEDO–33148 ‘‘is no longer cost
can impact plant risk (e.g., delayed a rulemaking would normally result in effective and, if ultimately approved in
LOOP and ‘‘double sequencing’’ 1 of NRC denial of the associated PRM for the form presently desired by NRC staff,
safety functions). the same reasons. adoption by licensees would most likely
In parallel with the LOOP/LOCA be prohibitively expensive.’’ The
III. Decoupling an Assumed Loss of withdrawal of NEDO–33148 and the
rulemaking, the NRC pursued a separate Offsite Power From a Loss-of-Coolant discontinued effort by the BWROG
Accident demonstrated a potential loss of
1 Double sequencing is defined as a situation
The Boiling Water Reactor Owners industry interest in this initiative.
asabaliauskas on DSKBBXCHB2PROD with PROPOSALS

where electrically powered safety and accident
mitigation equipment automatically start, shut Group (BWROG) submitted for NRC In SECY–09–0140, ‘‘Rulemaking
down, and restart in rapid succession when called review a licensing topical report NEDO– Related to Decoupling an Assumed Loss
on to operate. Delayed LOOP and double
sequencing were evaluated and dispositioned in
33148, ‘‘Separation of Loss of Offsite of Offsite Power From a Loss-of-Coolant
GSI–171, ‘‘ESF Failure from LOOP Subsequent to Power from Large Break LOCA,’’ dated Accident, 10 CFR part 50, Appendix A,
LOCA,’’ for the current regulations (https:// April 27, 2004 (ADAMS Accession No. General Design Criterion 35 (RIN 3150–
www.nrc.gov/sr0933/ ML041210900). The BWROG stated that AH43),’’ dated September 28, 2009
Section%203.%20New%20Generic%20Issues/
171r1.html#). GSI–171 does not need to be
the licensing topical report would (ADAMS Accession No. ML092151078),
reevaluated if the LOOP/LOCA rulemaking is support plant-specific exemption the NRC staff proposed three options for
discontinued. requests to implement plant changes the Commission to consider as a path

VerDate Sep<11>2014 17:28 Jun 19, 2017 Jkt 241001 PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 E:\FR\FM\20JNP1.SGM 20JNP1
Federal Register / Vol. 82, No. 117 / Tuesday, June 20, 2017 / Proposed Rules 28019

forward on the LOOP/LOCA (ADAMS Accession Nos. ML16203A003 IV. Petition for Rulemaking
rulemaking: (1) Discontinue the LOOP/ and ML16319A153, respectively) to (PRM–50–77)
LOCA rulemaking, (2) proceed with the receive external stakeholder feedback on
LOOP/LOCA rulemaking without the the need for a LOOP/LOCA rulemaking. On May 2, 2002, the NRC received a
BWROG topical report, or (3) continue The NRC presented information on what PRM from Bob Christie, Performance
to defer the LOOP/LOCA rulemaking would be required by the NRC and the Technology (ADAMS Accession No.
until implementation of the 50.46a industry to continue the proposed ML082530041), related to the topics in
ECCS rulemaking. The Commission rulemaking activity. The NRC’s position the proposed LOOP/LOCA rulemaking.
approved the third option, to defer the was similar to the March 24, 2008, letter The PRM requested that the NRC amend
LOOP/LOCA rulemaking, in the SRM to the BWROG detailing the information its regulations in appendix A to 10 CFR
for SECY–09–0140, dated July 2, 2010 that would be needed to complete part 50 to eliminate the requirement to
(ADAMS Accession No. ML101830056). review of licensing topical report assume a LOOP coincident with
In SECY–16–0009, NEDO–33148. Representatives from the postulated accidents. The NRC docketed
‘‘Recommendations Resulting from the Nuclear Energy Institute and the PWR the petition and assigned it Docket No.
Integrated Prioritization and Re- and BWR Owners Groups also presented PRM–50–77. The NRC published a
Baselining of Agency Activities,’’ dated their perspectives on continuing the notice of receipt and request for
January 31, 2016 (ADAMS Accession proposed LOOP/LOCA rulemaking comment on the PRM on June 13, 2002
No. ML16028A189), the NRC staff effort. The industry re-stated its view (67 FR 40622), and received one
recommended that the 50.46a ECCS from the 2008 withdrawal of the comment supporting the PRM from the
rulemaking be discontinued. In the SRM licensing topical report that the Strategic Teaming and Resource Sharing
for SECY–16–0009, dated April 13, 2016 estimated implementation costs would organization (ADAMS Accession No.
(ADAMS Accession No. ML16104A158), be prohibitively expensive for the ML022490192). The petition was
the Commission approved benefit received. In addition, industry resolved by a decision to consider its
discontinuing the 50.46a ECCS representatives recommended that the issues within the LOOP/LOCA
rulemaking. A Federal Register notice, NRC staff devote its resources to other rulemaking, but the petition remained
published on October 6, 2016 (81 FR risk-informed licensing activities that open because of the ongoing
69446), informed the public of the have significantly higher industry developments related to this
NRC’s decision to discontinue the interest, such as applications to rulemaking. However, in late 2007, the
50.46a ECCS rulemaking. implement 10 CFR 50.69, ‘‘Risk- NRC Executive Director for Operations
In support of the potential risk- informed categorization and treatment approved changes to the PRM process to
informed alternative to reliability of structures, systems and components enhance the efficiency and effectiveness
requirements in 10 CFR 50.46 and GDC for nuclear power reactors,’’ and risk- of dispositioning a PRM. As a result of
35, the NRC performed substantial work
informed technical specifications. those enhancements, the NRC closed
in a number of technical areas,
The NRC is discontinuing the LOOP/ this petition on April 13, 2009 (74 FR
including estimating LOCA frequencies
LOCA rulemaking activity. The current 16802), with a commitment to follow
and the conditional probability of a
regulations provide adequate protection through with the original resolution to
LOOP, given a LOCA (see memorandum
from A. Thadani to S. Collins, of public health and safety. This consider it within the LOOP/LOCA
‘‘Transmittal of Technical Work to rulemaking would have provided rulemaking.
Support Possible Rulemaking on a Risk- licensees an option to relax the current Because of the agency’s decision to
Informed Alternative to 10 CFR 50.46/ analysis requirements for considering a discontinue the LOOP/LOCA
GDC 35,’’ dated July 31, 2002 (ADAMS LOOP to occur coincident with a LOCA. rulemaking, the associated petition,
Accession No. ML022120661)). As part Based on the feedback from the PRM–50–77, is denied for the reasons
of this work, the NRC identified a industry, it is unlikely that any licensee discussed above. As provided at
number of areas of uncertainty would seek licensing basis changes that § 2.803(i)(2), the NRC has decided not to
associated with estimating the would rely on the proposed rulemaking. complete the rulemaking action and is
conditional probability of a LOOP, given The issues that caused the industry to documenting this denial of the PRM in
occurrence of a LOCA, including very withdraw the BWROG topical report in the docket for the closed PRM.
limited data on major ECCS actuations 2008 are still applicable today and the
and LOOPs after such actuations, industry has greater interest in the V. Conclusion
incomplete knowledge about all of the progress of other risk-informed
initiatives. Therefore, pursuit of this The NRC is no longer pursuing the
factors that can impact the probability of LOOP/LOCA rulemaking and is denying
consequential LOOP because of effort would likely have minimal
practical impact on safety. Based upon PRM–50–77 for the reasons discussed in
electrical transient factors,2 and the
(1) the assessment that there is no this document. In the next edition of the
impact on offsite system voltage due to
current adequate protection issue with Unified Agenda, the NRC will update
deregulation of the electric utility
respect to compliance with the current the entry for the rulemaking activity and
industry. To complete a fully developed
ECCS rule, (2) the lack of significant reference this document to indicate that
regulatory basis for the LOOP/LOCA
safety benefits from the rulemaking, (3) the rulemaking is no longer being
rulemaking, the NRC staff would need
to ensure that these areas of uncertainty the industry’s representation that it pursued. The rulemaking activity will
asabaliauskas on DSKBBXCHB2PROD with PROPOSALS

are adequately addressed as part of the would be unlikely for any licensee to appear in the completed actions section
rulemaking activity. voluntarily use the LOOP/LOCA rule of that edition of the Unified Agenda
On June 28, 2016, and October 26, because the estimated implementation but will not appear in future editions. If
2016, the NRC held public meetings costs would be prohibitively expensive the NRC decides to pursue a similar or
for the benefit received, and (4) the related rulemaking activity in the future,
2 As used here, transient factors include the
industry’s stated interest in pursuing it will inform the public through a new
electrical disturbance triggered by starting other risk-informed licensing activities, rulemaking entry in the Unified Agenda.
electrically powered safety and accident mitigation
equipment as a result of the LOCA and the the NRC is discontinuing the LOOP/ Dated at Rockville, Maryland, this 14th day
conditions of the offsite transmission system grid. LOCA rulemaking. of June 2017.

VerDate Sep<11>2014 17:28 Jun 19, 2017 Jkt 241001 PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 E:\FR\FM\20JNP1.SGM 20JNP1
28020 Federal Register / Vol. 82, No. 117 / Tuesday, June 20, 2017 / Proposed Rules

For the Nuclear Regulatory Commission. • Hand Delivery: Deliver to Mail Discussion
Annette L. Vietti-Cook, address above between 9 a.m. and 5
p.m., Monday through Friday, except On July 26, 2001, we issued AD 2001–
Secretary of the Commission.
Federal holidays. 16–01, Amendment 39–12369 (66 FR
[FR Doc. 2017–12792 Filed 6–19–17; 8:45 am]
40874, August 6, 2001) (‘‘AD 2001–16–
BILLING CODE 7590–01–P For service information identified in 01’’), for certain Airbus Model A330–
this NPRM, contact Airbus SAS, 301, –321, –322, –341, and –342
Airworthiness Office—EAL, 1 Rond airplanes, and certain Model A340
DEPARTMENT OF TRANSPORTATION Point Maurice Bellonte, 31707 Blagnac series airplanes. AD 2001–16–01 was
Cedex, France; telephone +33 5 61 93 36 prompted by reports of cracking in
Federal Aviation Administration 96; fax +33 5 61 93 45 80; email several structural parts of the aft cargo
airworthiness.A330-A340@airbus.com; compartment door. AD 2001–16–01
14 CFR Part 39 Internet http://www.airbus.com. You requires repetitive inspections to detect
may view this referenced service cracking of the aft cargo compartment
[Docket No. FAA–2017–0561; Directorate
Identifier 2016–NM–141–AD] information at the FAA, Transport door, and corrective action if necessary;
Airplane Directorate, 1601 Lind Avenue and also provides optional terminating
RIN 2120–AA64 SW., Renton, WA. For information on action for the repetitive inspections. We
the availability of this material at the issued AD 2001–16–01 to detect and
Airworthiness Directives; Airbus FAA, call 425–227–1221.
Airplanes correct cracking of the aft cargo
Examining the AD Docket compartment door, which could result
AGENCY: Federal Aviation in reduced structural integrity of the
Administration (FAA), DOT. You may examine the AD docket on airplane.
ACTION: Notice of proposed rulemaking the Internet at http://
www.regulations.gov by searching for On August 15, 2014, we issued AD
(NPRM). 2014–17–06, Amendment 39–17959 (79
and locating Docket No. FAA–2017–
SUMMARY: We propose to supersede 0561; or in person at the Docket FR 52181, September 3, 2014) (‘‘AD
Airworthiness Directive (AD) 2001–16– Management Facility between 9 a.m. 2014–17–06’’), for all Airbus Model
01, which applies to certain Airbus and 5 p.m., Monday through Friday, A330–200 series airplanes, Model
Model A330–301, –321, –322, –341, and except Federal holidays. The AD docket A330–200 Freighter series airplanes,
–342 airplanes, and certain Model A340 contains this proposed AD, the and Model A330–300 series airplanes.
series airplanes; and AD 2014–17–06, regulatory evaluation, any comments AD 2014–17–06 superseded AD 2011–
which applies to all Airbus Model received, and other information. The 17–08, Amendment 39–16772 (76 FR
A330–200 series airplanes, Model street address for the Docket Operations 53303, August 26, 2011). AD 2014–17–
A330–200 Freighter series airplanes, office (telephone 800–647–5527) is in 06 was prompted by a revision of
and Model A330–300 series airplanes. the ADDRESSES section. Comments will certain airworthiness limitations items
AD 2001–16–01 requires inspections for be available in the AD docket shortly documents, which specifies more
cracking of the aft cargo compartment after receipt. restrictive instructions and/or
door, and corrective action if necessary. airworthiness limitations. AD 2014–17–
FOR FURTHER INFORMATION CONTACT: 06 requires a revision to the
AD 2014–17–06 requires revising the
Vladimir Ulyanov, Aerospace Engineer, maintenance or inspection program, as
maintenance or inspection program, as
International Branch, ANM–116, applicable, to incorporate new or
applicable, to incorporate structural
Transport Airplane Directorate, FAA, revised structural inspection
inspection requirements. Since we
1601 Lind Avenue SW., Renton, WA requirements. We issued AD 2014–17–
issued AD 2001–16–01 and AD 2014–
98057–3356; telephone 425–227–1138; 06 to detect and correct fatigue cracking,
17–06, we have determined that more
fax 425–227–1149. damage, and corrosion in certain
restrictive maintenance instructions and
airworthiness limitations are necessary. SUPPLEMENTARY INFORMATION: structure, which could result in reduced
This proposed AD would require structural integrity of the airplane.
Comments Invited
revising the maintenance or inspection Since we issued AD 2001–16–01 and
program, as applicable, to incorporate We invite you to send any written AD 2014–17–06, we have determined
new or revised airworthiness limitation relevant data, views, or arguments about that more restrictive maintenance
requirements; and remove airplanes this proposed AD. Send your comments instructions and airworthiness
from the applicability. We are proposing to an address listed under the limitations are necessary, and that
this AD to address the unsafe condition ADDRESSES section. Include ‘‘Docket No. Model A340 series airplanes should be
on these products. FAA–2017–0561; Directorate Identifier removed from the applicability as there
DATES: We must receive comments on 2016–NM–141–AD’’ at the beginning of are currently no Model A340 series
this proposed AD by August 4, 2017. your comments. We specifically invite airplanes on the U.S. register.
ADDRESSES: You may send comments, comments on the overall regulatory, The European Aviation Safety Agency
using the procedures found in 14 CFR economic, environmental, and energy (EASA), which is the Technical Agent
11.43 and 11.45, by any of the following aspects of this proposed AD. We will for the Member States of the European
consider all comments received by the Union, has issued EASA Airworthiness
asabaliauskas on DSKBBXCHB2PROD with PROPOSALS

methods:
• Federal eRulemaking Portal: Go to closing date and may amend this Directive 2016–0152, dated July 27,
http://www.regulations.gov. Follow the proposed AD based on those comments. 2016 (referred to after this as the
instructions for submitting comments. We will post all comments we Mandatory Continuing Airworthiness
• Fax: 202–493–2251. receive, without change, to http:// Information, or ‘‘the MCAI’’), to correct
• Mail: U.S. Department of www.regulations.gov, including any an unsafe condition for all Airbus
Transportation, Docket Operations, M– personal information you provide. We Model A330–200 Freighter, –200, and
30, West Building Ground Floor, Room will also post a report summarizing each –300 series airplanes; and Model A340–
W12–140, 1200 New Jersey Avenue SE., substantive verbal contact we receive 200, –300, –500, and –600 series
Washington, DC 20590. about this proposed AD. airplanes. The MCAI states:

VerDate Sep<11>2014 17:28 Jun 19, 2017 Jkt 241001 PO 00000 Frm 00006 Fmt 4702 Sfmt 4702 E:\FR\FM\20JNP1.SGM 20JNP1
Document Created: 2017-06-20 02:20:32
Document Modified: 2017-06-20 02:20:32
Category		Regulatory Information
Collection		Federal Register
sudoc Class		AE 2.7: GS 4.107: AE 2.106:
Publisher		Office of the Federal Register, National Archives and Records Administration
Section		Proposed Rules
Action		Discontinuation of rulemaking activity and denial of petition for rulemaking.
Dates		Effective June 20, 2017, the rulemaking activity discussed in this document is discontinued and PRM-50-77 is denied.
Contact		Robert Beall, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; telephone: 301-415-3874; email: [email protected]
FR Citation		82 FR 28017
RIN Number		3150-AH43