ML22024A253

Rev. 0, Federal Register Notice

ML22024A253
Person / Time
Issue date:	08/16/2023
From:	Michael Eudy NRC/RES/DE/RGDB
To:
Karagiannis H
Shared Package
ML22024A165	List: ML22024A241 ML22024A245 ML22024A253 ML22159A226
References
DG-4030, NRC-2021-0133 RG-1.249, Rev 0
Download: ML22024A253 (5)

Text

[7590-01-P]

NUCLEAR REGULATORY COMMISSION

10 CFR Parts 50, 52 and 100

[NRC-2021-0133]

Regulatory Guide: Use of ARCON Methodology for Calculation of A ccident-

Related Offsite Atmospheric Dispersion Factors

AGENCY: Nuclear Regulatory Commission.

ACTION: Final guide; issuance.

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) is issuing a new

Regulatory Guide (RG) 1.249 (Revision 0), Use of ARCON Methodo logy for Calculation

of Accident-Related Offsite Atmospheric Dispersion Factors. Th is new RG describes an

approach for reactor applicants and licensees for determining a tmospheric relative

concentration (/Q) values in support of modeling onsite releases to offsite bounda ries

from a design-basis accident. Also, this RG implements the meth odology in RG 1.194,

Atmospheric Relative Concentrations for Control Room Radiologi cal Habitability

Assessments at Nuclear Power Plants, for offsite dose location s at boundaries.

DATES: Revision 0 to RG 1.249 is available on August 21, 2023.

ADDRESSES: Please refer to Docket ID NRC-2021- 0133 when contacting the NRC

about the availability of information regarding this document. You may obtain publicly

available information related to this document using any of the following methods:

• Federal Rulemaking Web Site: Go to https://www.regulations.gov and

search for Docket ID NRC-2021- 0133. Address questions about Dockets IDs in

Regulations.gov to Stacy Schumann; telephone: 301-415-0624; e-m ail:

Stacy.Schumann@nrc.gov. For technical questions, contact the in dividuals listed in the

FOR FURTHER INFORMATION CONTACT section of this document.

• NRCs Agencywide Documents Access and Management System

(ADAMS): You may obtain publicly available documents online in the ADAM S Public

Documents collection at https://www.nrc.gov/reading-rm/adams.html. To begin the

search, select Begin Web-based ADAMS Search. For problems wit h ADAMS, please

contact the NRCs Public Document Room (PDR) reference staff at 1-800-397-4209,

301-415-4737, or by e-mail to PDR.Resource@nrc.gov.

• NRCs PDR: You may examine and purchase copies of public documents,

by appointment, at the NRCs PDR, Room P1 B35, One White Flint North, 11555

Rockville Pike, Rockville, Maryland 20852. To make an appointm ent to visit the PDR,

please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-

4737, between 8 a.m. and 4 p.m. eastern time (ET), Monday throu gh Friday, except

Federal holidays.

Revision 0 to RG 1.249 and the regulatory analysis may be foun d in ADAMS

under Accession Nos. ML22024A241 and ML21165A007, respectively.

Regulatory guides are not copyrighted, and NRC approval is not required to

reproduce them.

FOR FURTHER INFORMATION CONTACT: Kevin Quinlan, Office of Nuclear Reactor

Regulation, telephone: 301-415-6809, email: Kevin.Quinlan@nrc. gov, or Jason White,

Office of Nuclear Reactor Regulation, telephone: 301-415-3212, email:

Jason.White@nrc.gov, or Harriet Karagiannis, Office of Nuclear Regulatory Research,

telephone: 301-415-2493, email: Harriet.Karagiannis@nrc.gov. A ll are staff of the U.S.

Nuclear Regulatory Commission, Washington, DC 20555-0001.

2 SUPPLEMENTARY INFORMATION:

I. Discussion

The NRC is issuing a new guide in the NRCs Regulatory Guide series.

This series was developed to describe methods that are acceptab le to the NRC staff for

implementing specific parts of the agencys regulations, to exp lain techniques that the

staff uses in evaluating specific issues or postulated events, and to describe information

that the staff needs in its review of applications for permits and licenses.

For clarification, Revision 0 of RG 1.249 was issued for publi c comment with a

temporary identification of Draft Regulatory Guide, DG-4030, to RG 4.28, titled, Use of

ARCON Methodology for Calculation of Accident-Related Offsite A tmospheric

Dispersion Factors. After further consideration of the applica bility of this RG the staff

decided that it is more suitable to be listed under the RGs of Division 1, titled, Power

Reactors. As a result, the RG number was changed to RG 1.249 u sing the same RG

title, instead of being listed under Division 4, titled, Envir onmental and Siting, as RG

4.28. The content of the RG did not change due to it being iss ued under Division 1 and

Division 4.

II. Additional Information

The NRC published a notice of the availability of DG-4030 (ML21165A005), in

the Federal Register on August 17, 2021 (86 FR 46024), for a 30-day public comment

period. The public comment period closed on September 16, 2021. The staff received

five comment submissions and a total of 30 public comments. Pub lic comments on DG-

4030 and the staff responses to the public comments are availab le under ADAMS under

Accession No. ML22024A245

This new RG provides guidance to industry for complying with an d implementing

the NRC requirements by endorsing the use of the ARCON computer code to calculate 3

offsite dispersion values out to distances of 1,200 m (3937 ft) that could include the

exclusion area boundary and/or low-population zone.

RG 1.194 (ML031530505) endorses the use of the ARCON96 computer code for

calculating accident-related onsite (control room and technical support center)

atmospheric dispersion values which are direct inputs to habita bility dose assessments.

In addition, RG 1.145 (ML12216A014) provides the present method ology incorporated

into the PAVAN computer code, as reviewed by the staff using NUREG-0800 at

https://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0 800/index.html

(ML070810350), Standard Review Plan (SRP) Section 2.3.4 for cal culating accident-

related related, offsite atmospheric dispersion values.

RG 1.249 will provide new guidance for applicants and licensees subject to Part

50 of title 10 of the Code of Federal Regulations (10 CFR), Domestic Licensing of

Production and Utilization Facilities; 10 CFR part 52, Licens es, Certifications, and

Approvals for Nuclear Power Plants; and 10 CFR part 100, Reac tor site criteria.

As noted in the Federal Register on December 9, 2022 (87 FR 75671), this

document is being published in the Rules section of the Federal Register to comply

with publication requirements under 1 CFR chapter I.

III. Congressional Review Act

This RG is a rule as defined in the Congressional Review Act (5 U.S.C. 801-808).

However, the Office of Management and Budget has not found it t o be a major rule as

defined in the Congressional Review Act.

IV. Backfitting, Forward Fitting, and Issue Finality

Issuance of RG 1.249, Revision 0, does not constitute backfitti ng as that term is

defined in 10 CFR 50.109, Backfitting and as described in NRC Management Directive

(MD) 8.4, Management of Backfitting, Forward Fitting, Issue Fi nality, and Information 4

Requests 8.4, Management of Backfitting, Forward Fitting, Issue Finality, an d

Information Requests (ML18093B087) ; constitute forward fitting as that term is defined

and described in MD 8.4; or affect issue finality of any approv al issued under 10 CFR

part 52. As explained in RG 1.249, applicants and licensees are not required to comply

with the positions set forth in this regulatory guide.

V. Submitting Suggestions for Improvement of Regulatory Guides

A member of the public may, at any time, submit suggestions to the NRC for

improvement of existing RGs or for the development of new RGs. Suggestions can be

submitted on the NRCs public website at https://www.nrc.gov/re ading-rm/doc-

collections/reg-guides/contactus.html. Suggestions will be con sidered in future updates

and enhancements to the Regulatory Guide series.

Dated: August 16, 2023.

For the Nuclear Regulatory Commission.

/RA/

Michael A. Eudy, Acting Chief, Regulatory Guide and Programs Management Branch, Division of Engineering, Office of Nuclear Regulatory Research.

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