Compliance With Order EA-13-109, Order Modifying Licenses With Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions, 70356-70358 [2013-28226]

Download as PDF 70356 Federal Register / Vol. 78, No. 227 / Monday, November 25, 2013 / Notices Section III (9) Is the purpose and goal of the proposed conceptual policy statement clear? If not, where is clarification needed? (10) Is the proposed conceptual RMRF policy statement useful in clarifying the Commission’s intent to use a riskinformed and performance-based defense-in-depth approach in performing its regulatory function? If not, what needs to be clarified? Section II (11) Should the current PRA policy statement (60 FR 42622, August 16, 1995) be replaced or subsumed/ incorporated into this policy statement? (12) What would be the benefit? What would be the detriment? Section III.B (13) If subsumed, is the proposed manner of incorporating the PRA statement reasonable? If not, why not? (14) Should the policy statement establish a Commission expectation that for all program areas, licensees and/or certificate holders are expected to have a risk analysis that is commensurate with the activity and technology? Section III.A (15) Do the proposed key elements in the RMRF process represent a complete and reasonable set? a. If not, what modifications should be made? b. Are other elements needed to cover the full spectrum of regulated activities? c. Are the elements sufficient to develop a consistent decisionmaking approach across all regulated activities? sroberts on DSK5SPTVN1PROD with NOTICES Section III.C (16) Should defense-in-depth be a key aspect of a RMRF? If not, why not? (17) Will such proposed draft policy statement be useful in determining the extent of defense-in-depth needed in each program area? (18) Is the approach proposed for characterizing defense-in-depth clear? If not, where is clarification needed? Is the strategy reasonable? If not, why not? (19) Is the definition provided for defense-in-depth clear? If not, why not? (20) Are the key attributes identified reasonable and complete? If not, why not? (21) Are the basic levels of prevention and mitigation reasonable? If not, why not? (22) Are the definitions of prevention and mitigation clear and reasonable? If not, why not? a. Are they sufficiently flexible to support all program areas? If not, where not? VerDate Mar<15>2010 17:53 Nov 22, 2013 Jkt 232001 b. Should and can these levels be further detailed (i.e., more specific) and still be sufficiently flexible to support all program areas? (23) Is it reasonable to expect the levels of defense to be independent such that failure of one level does not lead to failure of subsequent levels? If not, why not? a. Should the NRC accept different levels of rigor, or different levels of confidence, in demonstrating that there is independence between levels? Could the level of rigor vary depending upon the nature of the activity and the risks associate with loss of independence? b. Are there any other considerations that should be taken into account in determining the acceptable level of rigor or confidence in demonstrating independence between layers? (24) Is it reasonable to expect the following with regards to defense-indepth: a. Ensure appropriate barriers, controls, and personnel are available to prevent and mitigate exposure to radioactive material according to the hazard present, the credible scenarios, and the associated uncertainties; and b. Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low consistent with the applicable acceptance guidelines. c. Overall, ensure that each regulated activity has appropriate defense-indepth measures for prevention and mitigation of adverse events and accidents. d. If the expectations of a, b, or c are not reasonable, why not? (25) Are the proposed defense-indepth principles and decision criteria complete? Are they useful in deciding the extent of defense-in-depth needed in a program area? If not, how should they be improved? Section III.D (26) Are the proposed program area specific policy considerations clear and complete? If not, what modifications should be made? Are others needed to cover the full spectrum of regulated activities? Dated at Rockville, Maryland, this 4th day of November, 2013. For the Nuclear Regulatory Commission. Richard P. Correia, Director, Division of Risk Analysis, Office of Nuclear Regulatory Research. [FR Doc. 2013–28065 Filed 11–22–13; 8:45 am] BILLING CODE 7590–01–P PO 00000 Frm 00100 Fmt 4703 Sfmt 4703 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 Nuclear Regulatory Commission. ACTION: Interim Staff Guidance; Issuance. AGENCY: 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). SUMMARY: 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 https://www.regulations.gov and search for Docket ID NRC–2013–0215. Address questions about NRC dockets to Carol Gallagher; telephone: 301–287–3422; email: Carol.Gallagher@nrc.gov. 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 https://www.nrc.gov/readingrm/adams.html. To begin the search, select ‘‘ADAMS Public Documents’’ and then select ‘‘Begin Web-based ADAMS Search.’’ For problems with ADAMS, ADDRESSES: E:\FR\FM\25NON1.SGM 25NON1 Federal Register / Vol. 78, No. 227 / Monday, November 25, 2013 / Notices please contact the NRC’s Public Document Room (PDR) reference staff at 1–800–397–4209, 301–415–4737, or by email to pdr.resource@nrc.gov. 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 https:// www.nrc.gov/reading-rm/doccollections/#int. FOR FURTHER INFORMATION CONTACT: Dr. Rajender Auluck, Japan LessonsLearned Project Directorate, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555–0001; telephone: 301–415–1025; email: Rajender.Auluck@nrc.gov. SUPPLEMENTARY INFORMATION: sroberts on DSK5SPTVN1PROD with NOTICES 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 VerDate Mar<15>2010 17:53 Nov 22, 2013 Jkt 232001 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-indepth 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 1 ‘‘Order Modifying Licenses With Regard To Reliable Hardened Containment Vents (Effective Immediately),’’ EA–12–050 (March 12, 2012) (ADAMS Accession No. ML12056A043). PO 00000 Frm 00101 Fmt 4703 Sfmt 4703 70357 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. 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 E:\FR\FM\25NON1.SGM 25NON1 70358 Federal Register / Vol. 78, No. 227 / Monday, November 25, 2013 / Notices 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. Offices of the Corporation, Twelfth Floor Board Room, 1100 New York Avenue NW., Washington, DC STATUS: Meeting OPEN to the Public from 2 p.m. to 2:15 p.m. Closed portion will commence at 2:15 p.m. (approx.) MATTERS TO BE CONSIDERED: 1. President’s Report ´ 2. Tribute—Francisco J. Sanchez 3. Tribute—Lael Brainard 4. Minutes of the Open Session of the September 19, 2013 Board of Directors Meeting FURTHER MATTERS TO BE CONSIDERED: (Closed to the Public 2:15 p.m.): 1. Office of Accountability 2. Enterprise Risk Management 3. Minutes of the Closed Session of the September 19, 2013 Board of Directors Meeting 4. Reports 5. Pending Projects CONTACT PERSON FOR INFORMATION: Information on the meeting may be obtained from Connie M. Downs at (202) 336–8438. PLACE: Dated: November 22, 2013. Connie M. Downs, Corporate Secretary, Overseas Private Investment Corporation. [FR Doc. 2013–28305 Filed 11–21–13; 11:15 am] BILLING CODE 3210–01–P RAILROAD RETIREMENT BOARD [FR Doc. 2013–28226 Filed 11–22–13; 8:45 am] Proposed Collection; Comment Request BILLING CODE 7590–01–P OVERSEAS PRIVATE INVESTMENT CORPORATION Sunshine Act Meeting Notice— December 12, 2013 Board of Directors Meeting Thursday, December 12, 2013, 2 p.m. (OPEN Portion), 2:15 p.m. (CLOSED Portion). TIME AND DATE: necessary for the proper performance of the functions of the agency, including whether the information has practical utility; (b) the accuracy of the RRB’s estimate of the burden of the collection of the information; (c) ways to enhance the quality, utility, and clarity of the information to be collected; and (d) ways to minimize the burden related to the collection of information on respondents, including the use of automated collection techniques or other forms of information technology. 1. Title and purpose of information collection: Certification Regarding Rights to Unemployment Benefits; OMB 3220–0079. Under Section 4 of the Railroad Unemployment Insurance Act (RUIA), an employee who leaves work voluntarily is disqualified for unemployment benefits unless the employee left work for good cause and is not qualified for unemployment benefits under any other law. RRB Form UI–45, Claimant’s Statement— Voluntary Leaving of Work, is used by the RRB to obtain the claimant’s statement when the claimant, the claimant’s employer, or another source indicates that the claimant has voluntarily left work. Completion of Form UI–45 is required to obtain or retain benefits. One response is received from each respondent. The RRB proposes no changes to Form UI–45. Summary: In accordance with the requirement of Section 3506(c)(2)(A) of the Paperwork Reduction Act of 1995 which provides opportunity for public comment on new or revised data collections, the Railroad Retirement Board (RRB) will publish periodic summaries of proposed data collections. Comments are invited on: (a) Whether the proposed information collection is ESTIMATE OF ANNUAL RESPONDENT BURDEN [The estimated annual respondent burden is as follows] Annual responses Form No. Time (minutes) Burden (hours) 200 15 50 Total ...................................................................................................................................... sroberts on DSK5SPTVN1PROD with NOTICES UI–45 ........................................................................................................................................... 200 ........................ 50 2. Title and purpose of information collection: Railroad Separation Allowance or Severance Pay Report; OMB 3220–0173. Section 6 of the Railroad Retirement Act provides for a lump-sum payment to an employee or the employee’s VerDate Mar<15>2010 17:53 Nov 22, 2013 Jkt 232001 survivors equal to the Tier II taxes paid by the employee on a separation allowance or severance payment for which the employee did not receive credits toward retirement. The lumpsum is not payable until retirement benefits begin to accrue or the employee PO 00000 Frm 00102 Fmt 4703 Sfmt 4703 dies. Also, Section 4(a–1)(iii) of the Railroad Unemployment Insurance Act provides that a railroad employee who is paid a separation allowance is disqualified for unemployment and sickness benefits for the period of time the employee would have to work to E:\FR\FM\25NON1.SGM 25NON1

Agencies

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


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

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.

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

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 https://www.regulations.gov and search for Docket ID NRC-2013-0215. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-287-
3422; email: Carol.Gallagher@nrc.gov. 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 https://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 pdr.resource@nrc.gov. 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 https://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: Rajender.Auluck@nrc.gov.

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.
---------------------------------------------------------------------------

    \1\ ``Order Modifying Licenses With Regard To Reliable Hardened 
Containment Vents (Effective Immediately),'' EA-12-050 (March 12, 
2012) (ADAMS Accession No. ML12056A043).
---------------------------------------------------------------------------

    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

[[Page 70358]]

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
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