[Federal Register Volume 77, Number 63 (Monday, April 2, 2012)]
[Notices]
[Pages 19740-19741]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-7805]


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NUCLEAR REGULATORY COMMISSION

[NRC-2010-0249]


Water Sources for Long-Term Recirculation Cooling Following a 
Loss-of-Coolant Accident

AGENCY: Nuclear Regulatory Commission.

ACTION: Regulatory guide; issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC or the Commission) 
is issuing a revision to Regulatory Guide (RG) 1.82, ``Water Sources 
for Long-Term Recirculation Cooling Following a Loss-of-Coolant 
Accident.'' RG 1.82 describes methods that the NRC staff considers 
acceptable to implement requirements regarding the sumps and 
suppression pools that provide water sources for emergency core 
cooling, containment heat removal, or containment atmosphere cleanup 
systems. RG 1.82 provides guidelines for evaluating the adequacy and 
the availability of the sump or suppression pool for long-term 
recirculation cooling following a loss-of-coolant accident.

ADDRESSES: Please refer to Docket ID NRC-2010-0249 when contacting the 
NRC about the availability of information regarding this document. You 
may access information related to this document, which the NRC 
possesses and is publicly available, using the following methods:
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2010-0249. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-492-
3668; email: Carol.Gallagher@nrc.gov.
     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 pdr.resource@nrc.gov. Revision 4 of Regulatory 
Guide 1.82 is available

[[Page 19741]]

in ADAMS under Accession No. ML111330278. The regulatory analysis may 
be found in ADAMS under Accession No. ML111330285.
     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: John Burke, Mechanical and Electrical 
Engineering Branch or Richard Jervey, Regulatory Guide Development 
Branch, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, telephone (301) 251-7628 and 
(301) 251-7404 or email: John.Burke@nrc.gov and Richard.Jervey@nrc.gov.

SUPPLEMENTARY INFORMATION:

I. Introduction

    The NRC is issuing a revision to an existing guide in the agency's 
``Regulatory Guide'' series. This series was developed to describe and 
make available to the public information such as methods that are 
acceptable to the NRC staff for implementing specific parts of the 
agency's regulations, techniques that the staff uses in evaluating 
specific problems or postulated accidents, and data that the staff 
needs in its review of applications for permits and licenses.
    Revision 4 of Regulatory Guide (RG) 1.82, ``Water Sources for Long-
Term Recirculation Cooling Following a Loss-of-Coolant Accident,'' was 
issued with a temporary identification as Draft Regulatory Guide, DG-
1234. RG 1.82 describes methods that the NRC staff considers acceptable 
to implement requirements regarding the sumps and suppression pools 
that provide water sources for emergency core cooling, containment heat 
removal, or containment atmosphere cleanup systems. RG 1.82 provides 
guidelines for evaluating the adequacy and the availability of the sump 
or suppression pool for long-term recirculation cooling following a 
loss-of-coolant accident.

II. Further Information

    DG-1234 was published in the Federal Register on July 15 2010, (75 
FR 41241) for a 60-day public comment period. The public comment period 
closed on September 10, 2010. RG. 1.82, was first issued in June 1974. 
The NRC issued revisions to RG 1.82 in November 1985, May 1996, and 
November 2003 to incorporate gains in the understanding of containment 
sump performance, particularly debris blockage on the Emergency Core 
Cooling System (ECCS) strainers, and provide guidance in determining 
net positive suction head margin for the ECCS and the containment heat 
removal system. Since the November 2003 revision, (Revision 3), was 
issued supplemental information has been accumulated pertaining to ECCS 
performance accounting for in-plant considerations such as generation 
of debris and chemical effects associated with the debris circulating 
in the ECCS systems. Additionally, the NRC issued GL 2008-01, 
``Managing Gas Accumulation in Emergency Core Cooling, Decay Heat 
Removal, and Containment Spray Systems,'' in January 2008, to address 
gas accumulation in safety systems. The NRC obtained significant 
testing and analysis methodology information relative to pump 
characteristics affected by fluid voiding and gas transport as a 
function of system flow conditions which are germane to RG 1.82. This 
revision of RG 1.82 includes the latest information, and incorporates 
revised staff regulatory positions reflected in several safety 
evaluations performed upon ECCS performance testing results since the 
RG 1.82 Revision 3 was issued. Public comments on DG-1234 and the staff 
responses to the public comments are available in ADAMS under Accession 
No. ML111330292.

    Dated at Rockville, Maryland, this 16th day of March 2012.

    For the Nuclear Regulatory Commission.
Richard A. Jervey,
Acting Chief, Regulatory Guide Development Branch, Division of 
Engineering, Office of Nuclear Regulatory Research.
[FR Doc. 2012-7805 Filed 3-30-12; 8:45 am]
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