[Federal Register Volume 78, Number 181 (Wednesday, September 18, 2013)]
[Notices]
[Pages 57418-57419]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-22688]
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NUCLEAR REGULATORY COMMISSION
[NRC-2013-0215]
Compliance With Order EA-13-109, Order Modifying Licenses With
Regard to Reliable Hardened Containment Vents Capable of Operation
Under Severe Accident Conditions
AGENCY: Nuclear Regulatory Commission.
ACTION: Draft Japan Lessons-Learned Project Directorate guidance;
request for comment.
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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing this
draft Japan Lessons-Learned Project Directorate Interim Staff Guidance
(JLD-ISG), JLD-ISG-2013-02, ``Compliance with Order EA-13-109, Order
Modifying Licenses with Regard to Reliable Hardened Containment Vents
Capable of Operation under Severe Accident Conditions.'' (ADAMS
Accession No. ML13247A417) This draft JLD-ISG provides guidance and
clarification to assist nuclear power reactors applicants and licensees
with the identification of measures needed to comply with requirements
to mitigate challenges to key safety functions.
DATES: Comments must be filed no later than October 18, 2013. Comments
received after this date will be considered, if it is practical to do
so, but the NRC staff is able to ensure consideration only for comments
received on or before this date.
ADDRESSES: You may submit comment by any of the following methods
(unless this document describes a different method for submitting
comments on a specific subject):
Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2013-0215. Address
questions about NRC dockets to Carol Gallagher; telephone: 301-287-
3422; email: [email protected]. For technical questions, contact
the individual(s) listed in the FOR FURTHER INFORMATION CONTACT section
of this document.
Mail comments to: Cindy Bladey, Chief, Rules,
Announcements, and Directives Branch (RADB), Office of Administration,
Mail Stop: 3WFN, 06-44M, U.S. Nuclear Regulatory Commission,
Washington, DC 20555-0001.
For additional direction on accessing information and submitting
comments, see ``Accessing Information and Submitting Comments'' in the
SUPPLEMENTARY INFORMATION section of this document.
FOR FURTHER INFORMATION CONTACT: Rajender Auluck, Japan Lessons-Learned
Project Directorate, Office of Nuclear Reactor Regulation, U.S. Nuclear
Regulatory Commission, Washington, DC 20555-0001; telephone: 301-415-
1025; email: [email protected].
SUPPLEMENTARY INFORMATION:
I. Accessing Information and Submitting Comments
A. Accessing Information
Please refer to Docket ID NRC-2013-0215 when contacting the NRC
about the availability of information regarding this document. You may
access publicly-available information related to this action by the
following methods:
Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2013-0215.
NRC's Agencywide Documents Access and Management System
(ADAMS): You may access publicly-available documents online in the NRC
Library 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 notice (if that document is
available in ADAMS) is provided the first time that a document is
referenced. The draft JLD-ISG-2013-02 is available in ADAMS under
Accession No. ML13247A417.
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.
NRC's Interim Staff Guidance Web site: JLD-ISG documents
are also available online under the ``Japan Lessons Learned'' heading
at http://www.nrc.gov/reading-rm/doc-collections/#int.
B. Submitting Comments
Please include Docket ID NRC-2013-0215 in the subject line of your
comment submission, in order to ensure that the NRC is able to make
your comment submission available to the public in this docket.
The NRC cautions you not to include identifying or contact
information that you do not want to be publicly disclosed in your
comment submission. The NRC posts all comment submissions at http://www.regulations.gov as well as entering the comment submissions into
ADAMS. The NRC does not routinely edit comment submissions to remove
identifying or contact information.
If you are requesting or aggregating comments from other persons
for submission to the NRC, then you should inform those persons not to
include identifying or contact information that they do not want to be
publicly disclosed in their comment submission. Your request should
state that the NRC does not routinely edit comment submissions to
remove such information before making the comment submissions available
to the public or entering the comment submissions into ADAMS.
II. Background Information
The NRC staff developed this draft JLD-ISG-2013-02 to provide
guidance and clarification to assist nuclear power reactor applicants
and licensees with the identification of methods needed to comply with
requirements to mitigate challenges to key safety functions. These
requirements are contained in Order EA-13-109, ``Order Modifying
Licenses with Regard to Reliable Hardened Containment Vents Capable of
Operation under Severe Accident Conditions'' (ADAMS Accession No.
ML13130A067). The draft ISG is not a substitute for the requirements in
Order EA-13-109, and compliance with the ISG is not a requirement. This
ISG is being issued in draft form for public comment to involve the
public in development of the implementing guidance.
The events at the Fukushima Dai-ichi nuclear power plant following
the March 2011, earthquake and tsunami highlight the possibility that
events such as rare natural phenomena could challenge the traditional
defense-in-depth protections related to preventing accidents,
mitigating accidents to prevent the release of radioactive materials,
and taking actions to protect the public should a release occur. At
Fukushima Dai-ichi, limitations in time and unpredictable conditions
associated with the accident significantly hindered attempts by the
operators to prevent core damage and containment failure. In
particular, the operators were unable to successfully operate the
containment venting system. These problems, along with venting the
containments under challenging conditions following the tsunami,
contributed to the progression of the accident from inadequate cooling
of the core leading to core damage, to compromising containment
functions from overpressure and over-temperature conditions, and to the
hydrogen explosions that destroyed the reactor
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buildings (secondary containments) of three of the Fukushima Dai-ichi
units. The loss of the various barriers led to the release of
radioactive materials, which further hampered operator efforts to
arrest the accidents and ultimately led to the contamination of large
areas surrounding the plant. Fortunately, the evacuation of local
populations minimized the immediate danger to public health and safety
from the loss of control of the large amount of radioactive materials
within the reactor cores.
The events at Fukushima reinforced the importance of reliable
operation of hardened containment vents during emergency conditions,
particularly, for small containments such as the Mark I and Mark II
designs. On March 12, 2012, the NRC issued Order EA-12-050 \1\
requiring the Licensees identified in Attachment 1 to this order to
implement requirements for a reliable hardened containment venting
system (HCVS) for Mark I and Mark II containments. Order EA-12-050
required licensees of BWR facilities with Mark I and Mark II
containments to install a reliable HCVS to support strategies for
controlling containment pressure and preventing core damage following
an event that causes a loss of heat removal systems (e.g., an extended
loss of electrical power). The NRC determined that the issuance of EA-
12-050 and implementation of the requirements of that order were
necessary to provide reasonable assurance of adequate protection of the
public health and safety.
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\1\ ``Order Modifying Licenses With Regard To Reliable Hardened
Containment Vents (Effective Immediately),'' EA-12-050 (March 12,
2012) (ADAMS Accession No. ML12056A043).
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While developing the requirements for a reliable HCVS in Order EA-
12-050, the NRC acknowledged that questions remained about maintaining
containment integrity and limiting the release of radioactive materials
if the venting systems were used during severe accident conditions. The
NRC staff presented options to address these issues, including the
possible use of engineered filters to control releases, for Commission
consideration in SECY-12-0157, ``Consideration of Additional
Requirements for Containment Venting Systems for Boiling Water Reactors
With Mark I and Mark II Containments'' (issued November 26, 2012).
Option 2 in SECY-12-0157 was to modify EA-12-050 to require severe
accident capable vents (i.e., a reliable HCVS capable of operating
under severe accident conditions). Other options discussed in SECY-12-
0157 included the installation of engineered filtered containment
venting systems (Option 3) and the development of a severe accident
confinement strategy (Option 4). In the Staff Requirements Memorandum
(SRM) for SECY-12-0157, dated March 19, 2013, the Commission approved
Option 2 and directed the staff to issue a modification to Order EA-12-
050 requiring licensees subject to that order to ``upgrade or replace
the reliable hardened vents required by Order EA-12-050 with a
containment venting system designed and installed to remain functional
during severe accident conditions.''
The requirements in this order, in addition to providing a reliable
HCVS to assist in preventing core damage when heat removal capability
is lost (the purpose of EA-12-050), will ensure that venting functions
are also available during severe accident conditions. Severe accident
conditions include the elevated temperatures, pressures, radiation
levels, and combustible gas concentrations, such as hydrogen and carbon
monoxide, associated with accidents involving extensive core damage,
including accidents involving a breach of the reactor vessel by molten
core debris. This order requires installation of reliable hardened
vents that will not only assist in preventing core damage when heat
removal capability is lost, but will also function in severe accident
conditions (i.e., when core damage has occurred). The safety
improvements to Mark I and Mark II containment venting systems required
by this order are intended to increase confidence in maintaining the
containment function following core damage events. Although venting the
containment during severe accident conditions could result in the
release of radioactive materials, venting could also prevent
containment structural and gross penetration leakage failures due to
overpressurization that would hamper accident management (e.g.,
continuing efforts to cool core debris) and ultimately result in
larger, uncontrolled releases of radioactive material.
On August 28, 2013, NEI submitted NEI 13-02, ``Industry Guidance
for Compliance with Order EA-13-109,'' Revision C2 (ADAMS Accession No.
ML13247A403), to provide specification for the development,
implementation, and maintenance of guidance in response to the order
regarding reliable hardened containment vents capable of operation
under severe accident conditions. This ISG endorses, with
clarifications and exceptions, the methodologies described in the
industry guidance document NEI 13-02.
Proposed Action
By this action, the NRC is requesting public comments on draft JLD-
ISG-2013-02. This draft JLD-ISG proposes guidance related to
requirements contained in Order EA-13-109, ``Order Modifying Licenses
With Regard to Reliable Hardened Containment Vents Capable of Operation
Under Severe Accident Conditions''. The NRC staff will make a final
determination regarding issuance of the JLD-ISG after it considers any
public comments received in response to this request.
Dated at Rockville, Maryland, this 11th day of September 2013.
For the Nuclear Regulatory Commission.
David L. Skeen,
Director, Japan Lessons-Learned Project Directorate, Office of Nuclear
Reactor Regulation.
[FR Doc. 2013-22688 Filed 9-17-13; 8:45 am]
BILLING CODE 7590-01-P