[Federal Register Volume 78, Number 227 (Monday, November 25, 2013)]
[Notices]
[Pages 70356-70358]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-28226]


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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: Interim Staff Guidance; Issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing 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.'' Agencywide Documents and 
Management System (ADAMS) Accession No. ML13130A067). This ISG provides 
guidance and clarifies the requirements in the order to assist the 
licensees that have Boiling Water Reactors with Mark I and Mark II 
Containments in the design and implementation of a containment venting 
system that is capable of a operation under severe accident conditions. 
This ISG also endorses, with clarifications, the industry guidance 
contained in Nuclear Energy Institute (NEI) 13-02, ``Industry Guidance 
for Compliance with Order EA-13-109,'' Revision 0 (ADAMS Accession No. 
ML13316A853).

ADDRESSES: 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. 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.
     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,

[[Page 70357]]

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 JLD-ISG-2013-02 is available in ADAMS under 
Accession No. ML13304B836.
     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.

FOR FURTHER INFORMATION CONTACT: Dr. 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:

Background Information

    The NRC staff developed 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). This ISG is 
not a substitute for the requirements in Order EA-13-109, and 
compliance with the ISG is not a requirement.
    On September 18, 2013 (78 FR 57418), the NRC staff issued a Federal 
Register notice (to request public comments on draft JLD-ISG-2013-02 
(ADAMS Accession No. ML13247A417)). In response, the NRC received 
comments from the Pilgrim Watch by letter dated October 18, 2013 (ADAMS 
Accession No. ML13294A461), Beyond Nuclear by letter dated October 18, 
2013 (ADAMS Accession No. ML13295A225), and Nuclear Energy Institute by 
letter dated October 18, 2013 (ADAMS Accession No. ML13295A494). 
Several of these comments have been previously submitted to the NRC for 
staff's consideration. The resolution of these comments is documented 
and publicly available (ADAMS Accession No. ML13310B299).
    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 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 
Order 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

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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 over pressurization that would 
hamper accident management (e.g., continuing efforts to cool core 
debris) and ultimately result in larger, uncontrolled releases of 
radioactive material.
    On November 7, 2013, NEI submitted NEI 13-02, ``Industry Guidance 
for Compliance with Order EA-13-109,'' Revision 0 (ADAMS Accession No. 
ML13316A853) 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, the methodologies described in the industry guidance 
document NEI 13-02.

    For the Nuclear Regulatory Commission.

    Dated at Rockville, Maryland, this 14th day of November 2013.
David L. Skeen,
Director, Japan Lessons-Learned Project Directorate, Office of Nuclear 
Reactor Regulation.
[FR Doc. 2013-28226 Filed 11-22-13; 8:45 am]
BILLING CODE 7590-01-P