Accident Source Term Methodologies and Corresponding Release Fractions
| Published date | 24 August 2020 |
| Citation | 85 FR 52058 |
| Record Number | 2020-17645 |
| Section | Proposed rules |
| Court | Nuclear Regulatory Commission |
Federal Register, Volume 85 Issue 164 (Monday, August 24, 2020)
[Federal Register Volume 85, Number 164 (Monday, August 24, 2020)]
[Proposed Rules]
[Pages 52058-52059]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-17645]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 85, No. 164 / Monday, August 24, 2020 /
Proposed Rules
[[Page 52058]]
NUCLEAR REGULATORY COMMISSION
10 CFR Part 50
[Docket No. PRM-50-122; NRC-2020-0150]
Accident Source Term Methodologies and Corresponding Release
Fractions
AGENCY: Nuclear Regulatory Commission.
ACTION: Petition for rulemaking; notification of docketing and request
for comment.
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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) has received a
petition for rulemaking from Brian Magnuson dated May 31, 2020,
requesting that the NRC revise its regulations to codify the source
term methodologies and corresponding release fractions recommended in a
report issued by Sandia National Laboratories. The petition was
docketed by the NRC on June 18, 2020, and has been assigned Docket No.
PRM-50-122. The NRC is examining the issues raised in PRM-50-122 to
determine whether they should be considered in rulemaking. The NRC is
requesting public comment on this petition at this time.
DATES: Submit comments by November 9, 2020. Comments received after
this date will be considered if it is practical to do so, but the NRC
is able to assure consideration only for comments received on or before
this date.
ADDRESSES: You may submit comments by any of the following methods:
Federal Rulemaking website: Go to https://www.regulations.gov and search for Docket ID NRC-2020-0150. Address
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions contact
the individual listed in the FOR FURTHER INFORMATION CONTACT section of
this document.
Email comments to: [email protected]. If you do
not receive an automatic email reply confirming receipt, then contact
us at 301-415-1677.
Mail comments to: Secretary, U.S. Nuclear Regulatory
Commission, Washington, DC 20555-0001, ATTN: Rulemakings and
Adjudications Staff.
For additional direction on obtaining information and submitting
comments, see ``Obtaining Information and Submitting Comments'' in the
SUPPLEMENTARY INFORMATION section of this document.
FOR FURTHER INFORMATION CONTACT: Juan Lopez, Office of Nuclear Material
Safety and Safeguards, telephone: 301-415-2338, email:
[email protected], or Yanely Malave-Velez, Office of Nuclear Material
Safety and Safeguards, telephone: 301-415-1519, email: [email protected]. Both are staff of the U.S. Nuclear Regulatory
Commission, Washington, DC 20555-0001.
SUPPLEMENTARY INFORMATION:
I. Obtaining Information and Submitting Comments
A. Obtaining Information
Please refer to Docket ID NRC-2020-0150 when contacting the NRC
about the availability of information for this action. You may obtain
publicly-available information related to this action by any of the
following methods:
Federal Rulemaking website: Go to https://www.regulations.gov and search for Docket ID NRC-2020-0150.
NRC's Agencywide Documents Access and Management System
(ADAMS): You may obtain publicly-available documents online in the
ADAMS Public Documents collection at https://www.nrc.gov/reading-rm/pdr.html. To begin the search, 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
(if it is available in ADAMS) is provided the first time that it is
mentioned in this document.
Attention: The PDR where you may examine and order copies
of public documents, is currently closed. You may submit your request
to the PDR via email at [email protected] or call 1-800-397-4209
between 8:00 a.m. and 4:00 p.m. (EST), Monday through Friday, except
Federal holidays.
B. Submitting Comments
Please include Docket ID NRC-2020-0150 in your comment submission.
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 will post all comment submissions at
https://www.regulations.gov as well as enter 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 into ADAMS.
II. The Petitioner and Petition
The petition for rulemaking (PRM) was filed by Brian Magnuson. The
petition requests the NRC revise its regulations in Sec. 50.67 of
title 10 of the Code of Federal Regulations (10 CFR), ``Accident source
term,'' to codify the source term methodologies and corresponding
release fractions recommended in Sandia National Laboratories Report
SAND2008-6601, ``Analysis of Main Steam Isolation Valve Leakage in
Design Basis Accidents Using MELCOR 1.8.6 and RADTRAD,'' dated October
2008 (ADAMS Accession No. ML083180196). The petitioner states that the
revision would eliminate inconsistences obtained from the use of
different source term methodologies and release fractions and would
provide the requisite means to ensure compliance with the underlying
regulations. The petition may be found in ADAMS under Accession No.
ML20170B161.
III. Discussion of the Petition
The petition states that much of the past and present source term
methodologies, including release fractions, used by nuclear power
plants to perform accident dose calculations are inaccurate and
nonconservative. The
[[Page 52059]]
petition requests that the NRC revise Sec. 50.67 to codify the source
term methodologies and recommendations of Sandia National Laboratories
report SAND2008-6601 and update and finalize related NRC guidance,
Draft Regulatory Guide DG-1199 (Proposed Revision 1 of Regulatory Guide
1.183), ``Alternative Radiological Source Terms for Evaluating Design
Basis Accidents at Nuclear Power Reactors,'' dated October 2009 (ADAMS
Accession No. ML090960464).
The petition describes the current NRC guidance as ``conceptually
inaccurate'' and ``nonconservative'' for calculations of radiological
release doses, quoting from Sandia Report SAND2008-6601:
. . .these findings conclude that the current regulatory
guidelines permitting the use of the fission product concentration
in the drywell atmosphere during the first two hours prior to
assumed vessel reflood is non-conservative for the purposes of
evaluating the dose resulting from MSIV leakage, in addition to
being conceptually inaccurate.
The petition also states that, despite the NRC acknowledging the
safety significance of accident source terms, the NRC has not yet
approved Draft Regulatory Guide DG-1199. As a result, the petitioner
believes accident doses have been undercalculated for over 25 years.
The petition indicates this would account for the uncertainties that
high burnup fuel pellets could be reduced to a powder form and
dispersed outside of the fuel rod during clad failure accidents (with
or without fuel melt), used by the Radiological Assessment System for
Consequence Analysis (RASCAL) calculation described in NUREG-1940,
``RASCAL 4: Description of Models and Methods,'' available online at
https://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1940/.
IV. Conclusion
The NRC determined that the petition meets the requirements for
docketing a petition for rulemaking under Sec. 2.803, ``Petition for
rulemaking--NRC action.'' The NRC will examine the merits of the issues
raised in PRM-50-122 and any comments received on this document to
determine whether these issues should be considered in rulemaking.
Dated: August 7, 2020.
For the Nuclear Regulatory Commission.
Annette L. Vietti-Cook,
Secretary of the Commission.
[FR Doc. 2020-17645 Filed 8-21-20; 8:45 am]
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