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Proposed Rule

Risk-Informed Changes to Loss-of-Coolant Accident Technical Requirements

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Information about this document as published in the Federal Register.

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Nuclear Regulatory Commission.


Supplemental proposed rule: Extension of comment period.


On August 10, 2009, the Nuclear Regulatory Commission (NRC) published for public comment a supplemental proposed rule that would amend the requirements that govern domestic licensing of production and utilization facilities and licenses, certifications, and approvals for nuclear power plants to allow current and certain future power reactor licensees and applicants to choose to implement a risk-informed alternative to the current requirements for analyzing the performance of emergency core cooling systems (ECCS) during loss-of-coolant accidents (LOCA). The proposed amendments would also establish procedures and acceptance criteria for evaluating certain changes in plant design and operation based upon the results of the new analyses of ECCS performance.

The public comment period for this supplemental proposed rule is scheduled to close on September 24, 2009. The NRC has received a request to extend the comment period by 120 days. The NRC is granting this request and is also extending the comment period for the information collection aspects of this supplemental proposed rule by 60 days.


The comment period for the supplemental proposed rule, published August 10, 2009, (74 FR 40006), is extended by 120 days and now expires on January 22, 2010. The comment period for the information collection aspects of this proposed rulemaking is extended by 60 days and now expires on November 9, 2009. Comments received after these dates will be considered if it is practical to do so, but the Commission is able to ensure consideration only for comments received before these dates.


You may submit comments by any one of the following methods. Comments submitted in writing or in electronic form will be posted on the NRC Web site and on the Federal rulemaking Web site Because your comments will not be edited to remove any identifying or contact information, the NRC cautions you against including any information in your submission that you do not want to be publicly disclosed. The NRC requests that any party soliciting or aggregating comments received from other persons for submission to the NRC inform those persons that the NRC will not edit their comments to remove any identifying or contact information, and therefore, they should not include any information in their comments that they do not want publicly disclosed.

Federal e-Rulemaking Portal: Go to and search for documents filed under Docket ID [NRC-2004-0006]. Address questions about NRC dockets to Carol Gallagher, telephone (301) 492-3668; e-mail

Mail comments to: Secretary, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, ATTN: Rulemakings and Adjudications Staff.

E-mail comments to: If you do not receive a reply e-mail confirming that we have received your comments, contact us directly at (301) 415-1677.

Fax comments to: Secretary, U.S. Nuclear Regulatory Commission at (301) 492-3446.

You can access publicly available documents related to this document using the following methods:

NRC's Public Document Room (PDR): The public may examine and have copied for a fee publicly available documents at the NRC's PDR, Public File Area O-1F21, One White Flint North, 11555 Rockville Pike, Rockville, Maryland.

NRC's Agencywide Documents Access and Management System (ADAMS): Publicly available documents created or received at the NRC are available electronically at the NRC's Electronic Reading Room at​reading-rm/​adams.html. From this page, the public can gain entry into ADAMS, which provides text and image files of NRC's public documents. If you do not have access to ADAMS or if there are problems in accessing the documents located in ADAMS, contact the NRC's PDR reference staff at 1-800-397-4209, or (301) 415-4737, or by e-mail to

Federal Rulemaking Web site: Public comments and supporting materials related to this proposed rule can be found at by searching on Docket ID: NRC-2004-0006.

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Richard Dudley, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone (301) 415-1116, e-mail

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In a letter dated August 18, 2009 (ADAMS Accession No. ML092320126), the Nuclear Energy Institute (NEI) requested that the NRC extend the public comment period for the risk-informed ECCS rule by an additional 120 days. In its letter, NEI stated:

[I]mplementation of the rule as currently drafted would require technical analyses in a wide variety of areas. It is therefore necessary to solicit input from numerous sources in developing comments on the draft supplemental proposed rule, and NEI is coordinating industry comments with the NSSS owners groups, vendors, and licensees to ensure that the comments submitted by industry are of high quality and that they reflect a consensus industry perspective. However, the comment period provided in the August 10th Federal Register Notice is insufficient given the volume and breadth of material that requires a thorough technical review. Extending the comment period would provide the time necessary to fully assess the impact of the draft supplemental proposed rule and arrive at a set of comments that are of highest value to the NRC staff in considering this important rulemaking.

In view of the NRC's desire to receive high quality comments from external stakeholders who would be directly affected by the supplemental proposed rule and recognizing the quantity of information to be analyzed and the Start Printed Page 48668coordination efforts needed by and among those stakeholders, the comment period for the proposed rulemaking will be extended for all stakeholders for an additional 120 days. The comment period for the information collection aspects of this proposed rulemaking will be extended by 60 days. The NRC believes that these extensions will allow sufficient time for all stakeholders to develop and provide meaningful comments on the proposed rule.

The comment submittal deadline for the proposed rule is extended from the original September 24, 2009, deadline to January 22, 2010, and the information collection analysis comment deadline is extended from the original September 9, 2009, deadline to November 9, 2009.

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Dated at Rockville, Maryland, this 18th day of September 2009.

For the Nuclear Regulatory Commission.

Bruce S. Mallett,

Acting Executive Director for Operations.

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[FR Doc. E9-23043 Filed 9-23-09; 8:45 am]