[Federal Register Volume 75, Number 186 (Monday, September 27, 2010)]
[Proposed Rules]
[Pages 59160-59167]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-24137]


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NUCLEAR REGULATORY COMMISSION

10 CFR Chapter I

[NRC-2009-0279]


Radiation Protection Regulations and Guidance; Public Meetings 
and Request for Comments

AGENCY: U.S. Nuclear Regulatory Commission (NRC).

ACTION: Notice of Public Meeting and Request for Comment.

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SUMMARY: The NRC is conducting a series of public meetings, in the 
format of facilitated roundtable workshops, to solicit early public 
input on major issues associated with potential updates to NRC's 
radiation protection regulations and guidance in light of 
recommendations presented in the International Commission on 
Radiological Protection (ICRP) Publication 103 (2007). To aid in that 
process, the NRC is requesting comments on the issues discussed in this 
notice. The NRC has not initiated rulemaking on this subject, and is 
seeking early input and views on the benefits and impacts of options to 
be considered before making any decision on whether to proceed with a 
rulemaking. Each meeting will include a panel of participants, selected 
in a convening process to represent the

[[Page 59161]]

diversity of stakeholders for these issues, including the various uses 
of radioactive materials licensed by the NRC. In addition to the panel, 
the NRC is encouraging observation and participation by all interested 
individuals. The meeting agenda will specifically include opportunities 
for viewpoints to be expressed from individuals in attendance who are 
not members of the panel. The NRC plans to transcribe the meetings.

DATES: Comments on this notice should be submitted by January 31, 2011. 
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.
    Public Meeting Dates: The NRC will take public comments on the 
issues raised in this notice at a series of three 2-day public meetings 
that will be held during the weeks of October 25, 2010 (Washington, 
DC); November 1, 2010 (Los Angeles, California) and November 8, 2010 
(Houston, Texas). The meeting in Washington DC will also include a 
third day of discussions, focused more specifically on the issues 
associated with power reactor licensees, as described in Section IV of 
this notice. Specific locations and dates will be announced on the NRC 
public Web site at http://www.nrc.gov/public-involve/public-meetings/index.cfm. Please refer to the SUPPLEMENTARY INFORMATION section for 
additional information.

ADDRESSES: Members of the public are invited and encouraged to submit 
comments by any of the following methods:
    1. Mail to Cindy Bladey, Chief, Rules, Announcements and Directives 
Branch, Office of Administration, Mail Stop 5B01M, U.S. Nuclear 
Regulatory Commission, Washington, DC 20555-0001; or
    2. Electronically at http://www.regulations.gov.
    Comments will be made available to the public in their entirety. 
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.
    You can access publicly available documents related to this notice 
using the following methods:
    Regulations.gov: Documents related to this notice, including public 
comments, are accessible at http://www.regulations.gov.
    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 Document Access and Management System (ADAMS): 
Publicly available documents created or received at the NRC after 
November 1, 1999, are available electronically at the NRC's Electronic 
Reading Room at http://www.nrc.gov/reading-rm/adams.html. From this 
site, 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 PDR Reference staff at 1-800-397-4209, 301-415-4737 
or by e-mail to [email protected].

FOR FURTHER INFORMATION CONTACT: Dr. Kimyata Morgan Butler, Office of 
Federal and State Materials and Environmental Management Programs, 
telephone (301) 415-0733, e-mail [email protected] or Dr. 
Donald Cool, Office of Federal and State Materials and Environmental 
Management Programs, telephone (301) 415-6347, e-mail 
[email protected].

SUPPLEMENTARY INFORMATION:

I. Background

    Regulations issued by the U.S. Nuclear Regulatory Commission (NRC) 
are found in Chapter I of Title 10, ``Energy,'' of the Code of Federal 
Regulations (10 CFR). Chapter I is divided into Parts 1 through 199, 
which contain requirements that are binding for all individuals and 
entities that possess, use, or store nuclear materials or operate 
nuclear facilities under the NRC's jurisdiction. Of these, the 
regulations that are most relevant to the subject of this notice are 
contained in 10 CFR Part 20, ``Standards for Protection Against 
Radiation,'' and 10 CFR Part 50, ``Domestic Licensing of Production, 
and Utilization Facilities.'' Through the existing compatibility 
criteria, the NRC Agreement States have certain requirements that are 
essentially identical to 10 CFR Part 20 for their licensees. Additional 
requirements, specific to particular uses or classes of facilities, are 
found in other portions of the regulations. For example, 10 CFR Part 
35, ``Medical Use of Byproduct Material,'' contains requirements 
related to medical use of radioactive material. Other portions of the 
regulations also may contain radiation protection criteria, and cross 
references to 10 CFR Part 20.
    ICRP Publication 103 contains the latest in a series of revised 
international recommendations for radiation protection. Earlier 
recommendations of the ICRP concerning radiation protection were 
contained in ICRP Publication 2 (1959), ICRP Publication 26 (1977), and 
ICRP Publication 60 (1990). On December 18, 2008, the NRC staff 
provided a Policy Issue Notation Vote Paper (SECY-08-0197) to the 
Commission which presented the regulatory options of moving, or not 
moving, towards a greater degree of alignment between NRC's current 
radiation protection regulatory framework and the recommendations 
contained in ICRP Publication 103. In a Staff Requirements Memorandum 
(SRM) dated April 2, 2009, the Commission approved the staff's 
recommendation to immediately begin engagement with stakeholders and 
interested parties to ascertain the benefits, burdens, and potential 
stakeholder impacts if updates are made to NRC's radiation protection 
regulations and guidance in order to achieve greater alignment with the 
recommendations in ICRP Publication 103. This notice and series of 
public meetings are part of the NRC staff's ongoing engagement process.

II. Request for Written and Electronic Comments and Plans for a Public 
Meeting

    The NRC is soliciting comments on the technical issues and options, 
as presented in Sections III and IV of this notice. Comments may be 
submitted either in writing or electronically as indicated under the 
ADDRESSES heading. In addition, the NRC is holding a series of three 
public meetings, in the format of facilitated roundtable workshops, to 
be held during the weeks of October 25, 2010 (Washington, DC); November 
1, 2010 (Los Angeles, California); and November 8, 2010 (Houston, 
Texas). Specific locations and dates will be announced on the NRC 
public Web site at http://www.nrc.gov/public-involve/public-meetings/index.cfm.
    Sections III and IV provide background and topics of discussion on 
the major issues that will be the subject of the public meetings. 
During the public meetings, the NRC will conduct roundtable panel 
discussions, with a panel of participants, selected in a convening 
process to represent the

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diversity of stakeholders for these issues, including the various uses 
of radioactive materials licensed by the NRC. The meeting agenda will 
specifically include opportunities for viewpoints to be expressed from 
individuals in attendance who are not members of the panel. While all 
roundtable meetings will feature a discussion of technical issues and 
options for all types of licensed use of radioactive materials, as 
described in Section III of this notice, each meeting will have some 
degree of focus on particular types of licensed activity. The 
Washington, DC roundtable meeting will include a power reactor-focused 
session on the third day of the workshop, which will focus on issues 
described in Section IV of this notice. The roundtable meeting to be 
held in Los Angeles, California is intended to have additional medical 
use participation and the roundtable meeting held in Houston, Texas is 
intended to have additional industrial applications-focused (industrial 
radiography, well logging, etc.) participation. However, all interested 
stakeholders are encouraged to attend and participate in any of the 
three workshops, including representatives from the university, 
research, manufacturer and distributors, and other sectors that use 
radioactive materials.
    In addition to inviting public comments on the issues presented in 
Sections III and IV of this notice, the NRC is also requesting specific 
comments from potentially impacted industries. In Section III, the NRC 
is soliciting comments related to: (1) Information on the projected 
costs and benefits resulting from consideration of the factors 
described in Sections III; (2) operational data on radiation exposures 
from various licensee groups; (3) whether the presented issues are 
addressed comprehensively; and (4) whether other options should be 
considered. In Section IV, the NRC is requesting comments from the 
nuclear power industry, and other stakeholders, specifically on 
operational considerations and costs and benefits to the industry 
increasing alignment of 10 CFR Part 50, Appendix I design objectives 
with the recommendations of ICRP Publication 103. The Commission 
believes that stakeholder comments will help to identify and quantify 
the potential impact of these proposed changes and will assist the NRC 
as potential regulatory action(s) are developed. Based on the comments 
received, the Commission will then be in a better position to evaluate 
whether to proceed with the development of a proposed rulemaking. If 
the Commission decides to proceed with a proposed rulemaking, 
additional information will be published in the Federal Register for 
public review and comment.

III. NRC Staff-Identified Technical Issues and Options Associated With 
the Potential Revision of NRC's Radiation Protection Regulations and 
Guidance

Introduction

    Section A of the following discussion presents background 
information and describes some general considerations concerning 
potential revisions to NRC's radiation protection regulations, as 
identified by NRC staff. Section B discusses the various issues and 
options that need to be assessed before commencing regulatory 
activities related to initiating rulemaking to change current radiation 
protection regulations. All public feedback will be used in developing 
an options paper for Commission consideration in late 2011.

A. Background

    The Commission believes that the current NRC regulatory framework 
continues to provide adequate protection of health and safety of 
workers, the public, and the environment. From a safety regulation 
perspective, ICRP Publication 103 proposes measures that may be seen as 
going beyond what is needed to provide adequate protection. In order to 
ensure that the NRC is well informed of all the benefits and burdens 
associated with further alignment of NRC's current radiation protection 
regulations with ICRP Publication 103, the NRC is actively soliciting 
stakeholders' input to further clarify the issues, options, benefits, 
impacts, and/or burdens associated with making changes to the current 
NRC radiation protection regulations. These efforts include 
interactions with the public, the nuclear industry, the medical 
community, the radioactive materials community, States, and other 
Federal agencies (i.e., EPA, DOE, OSHA, etc.). The staff wishes to 
continue these interactions with more detailed stakeholder discussions 
during this series of facilitated roundtable workshops. The agenda for 
each workshop will feature the list of NRC staff-identified technical 
options and issues (described below) that are potential areas for 
revision of 10 CFR Part 20 in light of the recommendations contained in 
ICRP Publication 103. In addition, stakeholders and interested parties 
may introduce other options, issues, and information for the NRC's 
consideration.
    The current NRC radiation protection framework, taken as a whole, 
is a collection based on three different generations of international 
radiation protection guidelines. 10 CFR Part 20 is based upon the 1977 
recommendations contained in ICRP Publication 26, and the scientific 
information contained in ICRP Publication 30. In addition, 10 CFR Part 
20 contains certain requirements based on recommendations and materials 
provided by the U.S. National Council on Radiation Protection and 
Measurements. Some other NRC requirements, including those for 10 CFR 
Part 50 Appendix I, are based on the older recommendations from 1959 
contained in ICRP Publication 2. Certain licensees, as provided in 
specific license conditions, are implementing the more recent 
recommendations from 1990 in ICRP Publication 60 and subsequent 
publications updating the scientific information. The situation in 
other agencies of the Federal Government is similarly diverse, with 
requirements and guidance values based on all three previous 
generations of ICRP recommendations.
    The recommendations in ICRP Publication 103 continue to be based on 
the fundamental principles of justification of exposures, optimization 
of protection, and limitation of dose. ICRP Publication 103 
consolidates recommendations from ICRP Publication 60 and subsequent 
publications using a better integrated approach to radiation protection 
and in dealing with various types of radiation exposures. Among others 
things, exposures are divided into three fundamental exposure 
situations, planned exposure situations, existing exposure situations, 
and emergency exposure situations. Planned exposure situations include 
licensed activities where planning and controls are in place before the 
exposure is permitted. In each exposure situation, ICRP has placed an 
increased emphasis on the optimization of protection for such types of 
exposure situations. NRC regulations in 10 CFR Parts 20 and 50 are part 
of requirements in the United States for planned exposure situations, 
as described by the ICRP.

B. Issues and Options for Discussion

    The following format is used in the presentation of the issues that 
follow. Each issue is assigned a number, a short title, regulatory 
options, and a list of questions. These issues, options, and questions 
are not meant to be a complete or final list, but are intended

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to initiate discussion. Interested stakeholders are welcome to 
recommend additions, deletions, or modifications of the key issues for 
consideration and propose implementation considerations. These issues 
and options will serve as the basis for discussion at the public 
meetings. Meeting participants, and those wishing to make comments, are 
strongly encouraged to read more about this effort at http://www.nrc.gov/about-nrc/regulatory/rulemaking/opt-revise.html.
Issue No. 1: Effective Dose and Numerical Values
    Currently, 10 CFR Part 20 expresses the sum of internal and 
external exposures to an individual as the total effective dose 
equivalent (TEDE). In particular, the Commission amended the 
definitions in 10 CFR 20.1003 and 50.2 (72 FR 68058; December 4, 2007) 
to clarify the definition of TEDE to mean the sum of the effective dose 
equivalent (for external exposures) and the committed effective dose 
equivalent (for internal exposures). This action was made effective on 
February 15, 2008 (72 FR 72233; December 20, 2007). The revised 
definition of TEDE allows a licensee to substitute ``effective dose 
equivalent'' for ``deep dose equivalent'' (DDE) for external exposures, 
when calculated using a method found satisfactory to the Commission. 
Regulatory Guide 8.40 ``Methods for Measuring Effective Dose Equivalent 
from External Exposure'' recently updated and consolidated the guidance 
available on acceptable methods for calculation of effective dose. A 
conforming change was made to 10 CFR 20.1201(c) to clarify the 
determination of occupational radiation dose for adults. The rule 
change is consistent with the current recommendations of the ICRP.
    The staff is considering whether it is appropriate to adopt current 
ICRP terminology and methodology throughout 10 CFR Part 20 and other 
portions of the regulations, by using the term TED instead of the term 
TEDE. ICRP publications no longer use the term TEDE or committed 
effective dose equivalent. The updated terminology has been associated 
with changes to various weighting factors within the calculation, but 
the underlying conceptual approach has remained the same.
    Another area of consideration is changing the radiation protection 
weighting factors and numerical values. The weighting factors for 
tissues (WT) and types of radiation (WR) are 
currently specified in 10 CFR Part 20 in the definitions section, and 
are based on the recommendations in ICRP Publication 26. ICRP 
Publication 103 recommendations provide new values for both quantities. 
Revising values for Annual Limits on Intake (ALI) and Derived Air 
Concentrations (DAC) is also an area of consideration. At this time, 
the ICRP is still in the process of developing a new set of dose 
coefficients, which will incorporate the revised radiation and tissue 
weighting factors and account for the latest biophysical models. The 
ICRP has indicated that the first volume of these new dose coefficients 
is expected in late 2011, although the publication of the complete set 
for occupational exposure and public exposure is not expected before 
2014.
    In considering Issue No. 1, the staff has identified two main 
issues and options that should be considered and discussed relative to 
effective dose and numerical values:
Issue No. 1.1: Clarifying Effective Dose Methodology and Assessing 
Implications for Licensee Compliance With Dose Limits and Changes to 
Terminology
    NRC staff wants to clarify, as stated above, that the revised 
definition of TEDE allows a licensee to substitute EDE for deep dose 
equivalent (DDE) for external exposures and that a conforming change 
was made to 10 CFR 20.1201(c) to clarify the determination of 
occupational radiation dose for adults. The issue of terminology goes 
beyond the simple introduction of a new term. Some of the NRC 
regulations continue to be based on older radiation protection 
approaches, and if these approaches are changed, then a question would 
be whether to make a change in the existing terminology of 10 CFR Part 
20, or to the current terminology used worldwide. See Section IV for 
particular considerations in the power reactor community.
    In consideration of the potential changes to terminology, the 
following three options should be considered:

    Options: 1.1a: No change in the current terminology (terminology 
remains TEDE).
    1.1b: Change the current regulation to align with the current 
ICRP Publication.
    103: Express as Total Effective Dose.
    1c: Allow use of either term.
    Questions: Q1.1-1: In terms of implementing the recently changed 
methodology for applying TEDE, are there any potential impacts on 
the ability to comply with the options for dose limits (DDE vs. 
TED)?
    Q1.1-2: What are the anticipated impacts on records and reports?
Issue No. 1.2: Numerical Values and Weighting Factors
    ICRP Publication 103 provided updated tissue and radiation 
weighting factors (WT, WR). In addition, the ICRP 
is in the process of revising the dose coefficients based on new 
values, models, and decay data. The weighting factors currently used in 
10 CFR Part 20 date from 1977, and the corresponding ALI and DAC values 
are presented in 10 CFR Part 20 Appendix B. The NRC staff also notes 
that the EPA is currently examining the values presented in Federal 
Guidance Reports 11 and 13, and is considering an update of these 
values. The difference between the ICRP values and the EPA values stems 
primarily from the use of a U.S. population cancer incidence and 
mortality analysis, instead of an average set of cancer incidence and 
mortality values for a worldwide population. In discussion with 
stakeholders to date, the majority have been generally in favor of 
updating the scientific information. However, no specific information 
related to potential impacts has been presented.
    The following are options and questions are related to this issue:

    Options: 1.2a: No change.
    1.2b: Change the current regulation to align with the current 
ICRP Publication.
    103: Update to new values, models, and radionuclide decay data.
    Questions: Q1.2-1: Are there any foreseen impacts of the timing 
(2014) of making changes to the current numerical values and 
weighting factors? Should NRC consider moving forward with a more 
limited set of radionuclides that would be available more quickly, 
and make subsequent amendments to add additional values as they are 
published by the ICRP?
    Q1.2-2: Should the NRC use the values developed by the EPA, 
which will be based on a US population, instead of the ICRP values, 
which are based on a more diverse world population?
Issue No. 2: Occupational Dose Limits
    The occupational dose limit of 10 rem (100 mSv) over 5 years, with 
a maximum of 5 rem (50 mSv) in any one year, recommended by ICRP in 
1990, was not incorporated into the last revision of 10 CFR Part 20 
because the recommendations were not available during the public 
comment period for the proposed rule. The ICRP recommendations have now 
been adopted, in some form, by the International Atomic Energy Agency 
in their International Basic Safety Standards (BSS), and by most of the 
other countries in the world. In some countries, the limits are as 
recommended by the ICRP. In other cases, the national authorities have

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chosen to require a single 2 rem (20 mSv) limit for occupational 
exposure. In the discussions with stakeholders that have already taken 
place, the occupational dose limits issue has also included discussion 
of the relationship between the limits, and any proposal related to 
establishing constraints for occupational exposure (see Issue No. 4).
    The NRC staff is aware from stakeholder interactions that there are 
significant global or trans-boundary considerations that are important 
to some licensees which would argue in favor of changes in the dose 
limits. The staff is also aware that many other licensees wish to leave 
the current NRC regulations as they are. Factors identified have 
included potential impacts to licensees who have occupationally exposed 
individuals who are currently receiving exposures in excess of 2 rem 
(20 mSv) in a year.
    The NRC staff has identified the following three options for 
changes to NRC's occupational dose limits:

    Options: 2.a: No change. Allow the dose limit to remain at 5 rem 
(50 mSv) per year.
    2.b: Change the current regulation to align with the current 
ICRP Publication 103: 10 rem (100 mSv) over 5 years, with a maximum 
of 5 rem (50 mSv) in any one year.
    2.c: Change the current regulation to align with the approach 
adopted by some other countries: yearly dose limit of 2 rem (20 
mSv).
    Questions: Q2-1: Are there any significant anticipated impacts 
in assessing and retaining dose histories for each individual in 
order to comply with a multi-year average?
    Q2-2: Are there any anticipated implementation impacts expected 
if the dose limit is decreased?
    Q2-3: Is there any information about the actual dose 
distributions for industrial and medical licensees? What are the 
trends for this data? Are the data available to share with the NRC?
    Q2-4: For the medical industry, are there any potential impacts 
on patient care?
Issue No. 3: Doses to Special Populations
Issue No. 3.1: Dose Limits for Embryo/Fetus of a Declared Pregnant 
Worker
    The limits for the embryo/fetus of a declared pregnant worker are 
specified in 10 CFR 20.1208. Currently, the dose limit to the embryo/
fetus of a declared pregnant worker is 0.5 rem (5 mSv) for the 
gestation period with 0.05 rem (0.5 mSv) additional dose during the 
gestation period if the dose to the embryo/fetus has already exceeded 
0.5 rem (5 mSv) at the time of declaration. The current requirements 
are based on the recommendations available in ICRP Publication 26. The 
ICRP recommendations now state that protection should be provided that 
is generally equivalent to that provided to a member of the public. 
Thus, the ICRP has now recommended a simplified approach, which is 100 
mrem (1 mSv) after the declaration of pregnancy.
    In the discussions with stakeholders that have already taken place, 
many stakeholders have indicated that the ICRP proposal would not cause 
any issues. However, the NRC staff is also aware of some licensee 
segments, such as Nuclear Pharmacy licensees, where the change could 
result in an impact. To date, specific information and supporting data 
on impacts have not been received.
    The NRC staff identified the following three options for the dose 
limit to an embryo/fetus of a declared pregnant worker:

    Options: 3.a: No change. Continue with the dose limit of 0.5 rem 
(5 mSv) per year.
    3.b: Change the current regulation to align with the current 
ICRP Publication 103: 100 mrem (1 mSv) after the declaration of 
pregnancy. 3.c: Change the current regulation to another single 
value after declaration: For example, 0.05 rem (.5 mSv) after 
declaration, the provision of the current rule if a dose of 0.5 rem 
(5 mSv) has already been exceeded at the time of declaration of the 
pregnancy.
    Questions: Q3-1: Are there any significant anticipated impacts 
associated with reducing the dose limit to the embryo/fetus of a 
declared pregnant woman, including operational impacts?
    Q3-2: Are there any anticipated implementation impacts on record 
keeping?
    Q3-3: Is there a reduction in burden in assessment and record 
keeping if the ICRP recommendation is considered for adoption?
    Q3-4: Are there technological implementation issues, such as 
limits of detection, which would make adoption of the ICRP 
recommendation difficult in certain circumstances?
    Q3-5: Is there data on actual dose distributions to the embryo/
fetus of a declared pregnant worker? What are the trends for this 
data? Is this data available to share with the NRC?
Issue No. 3.2: Dose Limits for Members of the Public, Alternative 
Provisions for 500 mrem (5 mSv)
    In addition to the dose to the embryo/fetus of a declared pregnant 
female, stakeholders have asked about the implementation of the ICRP 
recommendations to sensitive populations. In particular, stakeholders 
have noted that the ICRP recommendations have stated that, although the 
dose limits for members of the public continue to provide flexibility 
for doses greater than 100 mrem (1 mSv) in certain limited 
circumstances, sensitive populations such as young children should not 
be allowed to receive doses greater than the dose limits. This leads to 
an issue regarding the public dose limits that the NRC staff has not 
previously solicited comments.
    The current NRC public dose limits in 10 CFR 20.1301 contain a 
provision that allows for licensees to apply for a limited application 
of a dose limit up to 500 mrem (5 mSv). In consideration of the ICRP's 
latest set of recommendations, the following options have been 
identified:

    Options: 3.2-a: No change. Continue to allow a dose limit of 0.5 
rem (5 mSv) per year, applicable only upon specific approval of a 
licensee request.
    3.2-b: Change the current regulation to limit the applicability 
of the provision to situations in which sensitive populations are 
not receiving the exposure.
    3.2-c: Clarify in guidance that the NRC will require licensees 
to demonstrate that sensitive populations are not included in any 
proposals for alternative public dose limits.
    Questions: Q3.2-1: Are there any significant anticipated impacts 
associated with limiting the applicability of alternative public 
dose limits?
    Q3.2-2: Are these impacts the same for the options of a rule 
change, or for changes to guidance?
    Q3.2-3: Is there data available about the actual use of the 
alternative dose criteria? Is this data available to share with the 
NRC?
Issue No. 4: Incorporation of Dose Constraints
    One of the most significant recommendations made in ICRP 
Publication 103 was the increased emphasis on the use of constraints 
and reference levels as part of the process of optimization of 
protection for all exposure situations. Licensees are currently 
required by 10 CFR 20.1101 to use sound radiation protection principles 
to achieve occupational doses and doses to members of the public that 
are `As Low As Is Reasonably Achievable (ALARA). The term, 
``constraint,'' is already included in the definitions of 10 CFR Part 
20. A constraint, as currently defined, is a value at which licensee 
actions are required. Many licensees are generally familiar with the 
concept of constraints, although the term may be unfamiliar, because 
the concept is very similar to the use of various types of planning 
values (such as self-imposed administrative limits) in their programs 
to ensure that the dose limits are not exceeded. Thus, many established 
radiation protection programs already incorporate this concept, at 
least to some degree. The ICRP recommendations indicate that the 
constraint is the starting point for optimization, serving as an upper 
bound on the annual dose for members of the public, or an 
occupationally exposed individual, should receive from the

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planned operation of any controlled source of radiation. ICRP has 
stated that constraints are not to be considered as limits. In the 
discussions with stakeholders that have already taken place, many 
stakeholders have asked questions about the concept of constraints, the 
relationship of constraints to limits, and the relationship between 
possible changes to the limits and the use of constraints. In the 
current NRC regulatory structure, a constraint is defined as a level at 
which a licensee action is required. This provision is applied to 
airborne effluents from non-reactor facilities, and the actions are to 
evaluate the situation, develop actions to return effluents levels to 
less than the constraint, and provide a report to the NRC. Thus, as 
presently used in the regulations, an effluent release in excess of the 
numerical value of the constraint is not a violation. A violation only 
occurs if actions are not implemented in response to the situation. 
This approach is similar to the description presented by the ICRP, 
where a dose in excess of the constraint would not be seen as a 
violation, but as a point when reevaluation of the planning and 
implementation of the optimization ALARA program is needed.
    A number of stakeholders have expressed an interest in exploring 
the implications of using the mandatory application of constraints as a 
mechanism to achieve the same level of protection as a change in dose 
limits, while retaining some flexibility on the part of the licensee to 
examine and control their own programs. The NRC staff is interested in 
continuing to explore these proposals and their implications from 
various groups of licensees.
    NRC staff has identified three options for the incorporation of 
dose constraints to NRC's radiation protection framework:

    Options: 4.a: No change. Do not incorporate the use of 
constraints into NRC's radiation protection framework.
    4.b: Change the current regulation to specify that licensees 
establish and use constraints as part of their radiation protection 
program and the implementation of the ALARA requirement.
    4.c: In addition to requiring the establishment and use of 
constraints, require that the licensee use a numeric value that does 
not exceed some specified value. One such value for occupational 
exposure could be the 2 rem (20 mSv) per year level.
    Questions: Q4-1: Are there any significant anticipated benefits 
and impacts associated with imposing the use of constraints in a 
licensee's radiation protection program?
    Q4-2: Are there any anticipated implementation impacts on 
inspection, compliance, and reporting anticipated?
    Q4-3: What relationship should a constraint have to the dose 
limit, if any?
    Q4-4: Is a requirement to establish and use constraints an 
appropriate, or inappropriate, insertion of a regulatory 
requirement?
    Q4-5: How familiar are you with the use and implementation of 
constraints or planning values in a radiation protection program?
    Q4-6: Are constraints (planning values) used in your current 
licensed activities, and if so, can you share insights on the use of 
these constraints?

IV. NRC Staff-Identified Technical Issues and Options Associated With 
the Possible Revision of 10 CFR Part 50, Appendix I Regulations and 
Guidance

    Section A of the following discussion presents background 
information and describes general considerations concerning potential 
revisions to NRC regulations controlling radioactive liquid and gaseous 
effluent releases in the environment, as identified by NRC staff. The 
regulations are contained in Appendix I to 10 CFR Part 50, ``Numerical 
Guides for Design Objectives and Limiting Conditions for Operation to 
Meet the Criterion `As Low as is Reasonably Achievable' for Radioactive 
Material in Light-Water-Cooled Nuclear Power Reactor Effluents.'' 
Section B discusses the various issues and options that need to be 
assessed before initiating any regulatory activities leading to a 
rulemaking proposing to align the dosimetry basis, current dose 
terminology, and dose calculation methods of 10 CFR Part 50, Appendix I 
design objectives with the recommendations of ICRP Publication 103.

A. Background

    In 1975, the NRC adopted the ALARA principle in regulating 
radioactive liquid and gaseous effluent releases from nuclear power 
plants. Radioactive liquid and gaseous effluents are controlled under 
10 CFR Part 20, 10 CFR Parts 50.34a and 50.36a, and Appendix I to 10 
CFR Part 50. 10 CFR Part 50, Appendix I contains provisions to ensure 
that gaseous and liquid radioactive effluents released in unrestricted 
areas and doses to members of the public are ALARA. These requirements 
are based on dosimetry concepts issued in 1959 as ICRP Publication 2. 
This approach was consistent with the version of Part 20 in effect 
prior to 1991, but is no longer consistent with current 10 CFR Part 20.
    The revision under consideration may propose the adoption of the 
radiation protection framework recommended by ICRP Publication 103. 
This NRC staff is considering the approach in parallel with the 
consideration of changes to 10 CFR Part 20 so that the resulting 
requirements can be consistent.
    The Commission believes that the current NRC regulatory framework 
of 10 CFR Part 50, Appendix I, and reactor oversight program continues 
to ensure that gaseous and liquid radioactive effluents released in 
unrestricted areas and doses to members of the public are ALARA. The 
alignment of 10 CFR Part 50, Appendix I regulations and design 
objectives with ICRP Publication 103 recommendations would not be 
intended to change the design objective criteria and regulatory 
guidance used by the nuclear power industry in demonstrating compliance 
with these requirements.

B. Issues and Options for Discussion

Issue No. 1: Proposed Revision to the Basis of 10 CFR Part 50, Appendix 
I Design Objectives
    Currently, the design objectives of 10 CFR Part 50, Appendix I, and 
associated guidance documents, are still based on ICRP Publication 2 
dosimetry concepts, which include dose to the whole body and to 
critical organs. The ICRP Publication 26 and ICRP Publication 103 
recommendations moved to a more risk-based approach, and expressed the 
dose limits as TEDE, a sum of external and internal radiation 
exposures. Currently, nuclear power plant licensees must apply two 
different methodologies in calculating doses, one in determining 
compliance with the requirements of 10 CFR Part 50, Appendix I, and 
another in calculating doses to members of the public under 10 CFR Part 
20. The intent of a possible revision is to align and improve 10 CFR 
Part 50, Appendix I regulations and guidance by incorporating current 
developments in radiation protection principles and advances in 
radiation dosimetry that have occurred since the issuance of ICRP 
Publication 2, over 50 years ago, and promulgation of 10 CFR Part 50 
and Appendix I in 1975.
    The staff has identified three main issues and options that should 
be considered and discussed relative to alignment with more recent 
recommendation:

    Options: 1.a: Leave the basis of 10 CFR Part 50, Appendix I 
design objectives as is and continue to apply the requirement under 
existing NRC guidance and industry practices. This approach argues 
that there is no necessary connection between 10 CFR Part 50, 
Appendix I design objectives and 10 CFR Part 20 dose limits to the 
public, given that 10 CFR Part 50, Appendix I is not a

[[Page 59166]]

radiation protection standard under 10 CFR Parts 50.34a. The 10 CFR 
Part 50, Appendix I design objectives are an ``ALARA design basis'' 
requirement. If the numerical guides for design objectives and ALARA 
provisions of 10 CFR Part 50, Appendix I are met, it constitutes a 
demonstration that effluent releases and associated doses to the 
public are ALARA and no additional efforts are required to reduce 
radioactive effluent releases. As a result, it could be argued that 
there is no need to link the two. This approach would result in 
minor revisions to supporting NRC guidance. The revision would 
require that a few regulatory guides, currently as draft, be 
finalized and re-issued as final.
    1.b: Align dose definitions and quantities of 10 CFR Part 50, 
Appendix I criteria with the ICPR 103 recommendations, in parallel 
with any changes made to 10 CFR Part 20. This approach argues that 
there is a benefit in aligning the basis of 10 CFR Part 50, Appendix 
I design objectives with 10 CFR Part 20, as updated to ICRP 
Publication 103 recommendations. This approach would ensure a 
consistent application of regulatory criteria between 10 CFR Part 20 
and 10 CFR Part 50. Such a revision could offer the opportunity to 
standardize the process to a common regulatory basis in calculating 
doses. This approach would result in significant revisions to 
supporting NRC guidance, including key regulatory guides, NUREG 
documents, and computer codes.
    1.c: Align dose definitions and quantities of 10 CFR Part 50, 
Appendix I design objectives with the current framework of 10 CFR 
Part 20 based on ICRP Publication 26. This approach has the same 
goal as option 1.2, and is offered as an option if the NRC decides 
to not update 10 CFR Part 20. As before, this approach would ensure 
a consistent application of regulatory criteria between 10 CFR Part 
20 and 10 CFR Part 50. The revision would result in standardization 
to a common but still outdated regulatory dosimetry basis and method 
in calculating doses. This approach would result in significant 
revisions to supporting NRC guidance, including key regulatory 
guides, regulatory guides (NUREG) documents, and computer codes.
    Questions: Q1-1: What are the benefits and impacts of each 
option identified above? Is there a preferred ranking of the 
options?
    Q1-2: What is the scope of operational impacts and costs in 
updating programs and procedures given a revision of 10 CFR Part 50, 
Appendix I design objectives and NRC guidance? Identify specific 
types of impacts that the NRC should consider in implementing a 
revision of 10 CFR Part 50, Appendix I design objectives and NRC 
guidance to ICRP Publication 103 recommendations.
    Q1-3: Are there estimates available for the costs to revise 
operational programs, implementing procedures, computer codes, and 
personnel training for a typical pressurized water reactor (PWR) and 
boiling water reactor (BWR) power plant or for a generic power 
plant? Is there an estimate of the aggregate cost for the operating 
fleet of nuclear power reactors?
    Q1-4: Should the NRC combine both 10 CFR Part 20 and 10 CFR Part 
50, Appendix I updates into one rulemaking effort, or consider two 
parallel rulemaking efforts with the implementation of the revised 
rules synchronized to a common implementation date when all 
regulatory conforming changes and revisions of implementing guidance 
are completed for 10 CFR Part 20 and 10 CFR Part 50, Appendix I?
Issue No. 2: Voluntary or Required Implementation of Revised 10 CFR 
Part 50, Appendix I Regulations
    This issue examines the different possibilities for implementation 
of a possible revision for existing licensee facilities. Voluntary 
implementation should not pose any backfitting considerations under the 
Backfit Rule (10 CFR 50.109). However, the staff would need to address 
the potential impacts on the reactor inspection program for those 
plants and new applicants that would voluntarily implement the revised 
regulations.

    Options: 2.a: No change. Leave the current requirements and 
guidance intact for all currently licensed and operating plants 
under Parts 50 and 52.
    2.b. Make the implementation of new requirements voluntary for 
all currently licensed and operating plants under Parts 50 and 52 
using a separate set of revised 10 CFR Part 50, Appendix I 
regulations and guidance.
    2.c. Require the implementation of revised 10 CFR Part 50, 
Appendix I regulations and guidance for all operating plants and 
applicants over time with a mandated common implementation date.
    Questions: Q2-1: If 10 CFR Part 50, Appendix I was revised, 
should the NRC make the implementation of the revised requirements 
voluntary or mandatory on all nuclear power plant licensees?
    Q2-2: If 10 CFR Part 50, Appendix I were revised and became 
mandatory, what should be the duration of the implementation phase 
for power plant licensees, e.g., 2, 4, or 6 years?
Issue No. 3: Approaches and Considerations in Revising 10 CFR Part 50, 
Appendix Regulations
    In addition to the possible update of dosimetric concepts and 
methods, there are a number of additional areas within 10 CFR Part 50 
Appendix I which could be considered for possible revision and update. 
The staff is examining a tiered set of options, reflecting increasing 
levels of complexity of the update, with the scope of the revision 
ultimately depending on the chosen option on how to proceed with the 
revisions, whether the implementation is mandated or voluntary, and 
taking full considerations of impacts on regulations and guidance.

    Options: 3.a: Limited Scope Revision--Besides specific revisions 
to the regulations, target only those elements of the guidance 
dealing with dose conversion factors and, if necessary, directly 
supporting radiological parameters, such as specific adjustments to 
the basis of dose conversion factors, based on ICRP Publication 103 
or ICRP Publications 26 and 30. The balance of the technical 
guidance and default values of other parameters would remain as 
stated in current regulatory guides. The revision would identify 
changes to computer codes using new dose conversion factors based on 
ICRP Publication 103 or ICRP Publications 26 and 30 recommendations.
    3.b: Expanded Scope Revision--In addition to the above, the 
basis of specific parameters used in dose calculations would be 
evaluated, and an assessment would identify the need to update or 
retain specific default values. Such parameters, for example, would 
include human food or animal consumption rates, bio-accumulation 
factors, shore-line width factors, agricultural productivity rates, 
usage and time factors for exposed individuals, etc. The revision 
would also identify changes to computer codes using new dose 
conversion factors based on ICRP Publication 103 or ICRP 
Publications 26 and 30 recommendations.
    3.c: Full Scope Revision--This approach would consider a full 
review of the guidance, including a complete update of models 
addressing liquid and gaseous treatment options and development of 
radiological effluent source terms, atmospheric and aquatic 
dispersion, and environmental transport using the current literature 
and industry standards. The review would assess model assumptions, 
parameters (as partly described above), and their default values. 
The revision would identify changes to computer codes, modeling 
assumptions and parameters, and apply new dose conversion factors 
based on ICRP Publication 103 or ICRP Publications 26 and 30 
recommendations.
    Questions: Q3-1: Which option should the NRC apply in aligning 
10 CFR Part 50, Appendix I regulations with ICRP Publication 103 if 
10 CFR Part 20 were revised, or with ICRP Publications 26 and 30 if 
10 CFR Part 20 were not revised?
    Q3-2: What are the impacts and benefits in the implementation of 
revised 10 CFR Part 50, Appendix I regulations that the NRC should 
consider?
    Q3-3: If significant impacts in the implementation of revised 10 
CFR Part 50, Appendix I regulations are envisioned, what types of 
issues should the NRC evaluate and consider in revising 10 CFR Part 
50, Appendix I regulations?
Issue No. 4: Scope of Revisions to 10 CFR Part 50, Appendix I 
Regulations
    At this time, the NRC assumes that any proposed revision to 10 CFR 
Part 50, Appendix I will be multi-fold. One aspect involves conforming 
changes in ensuring that the nomenclature used in defining doses and 
dosimetric quantities, as described in Issue 1 above. The 
implementation of conforming changes in regulations and guidance is 
expected to be a relatively simple process, once all nomenclatures and 
definitions have been finalized and

[[Page 59167]]

integrated in a revised 10 CFR Part 20. However, some challenges are 
expected in modifying some of the regulatory provisions of Appendix I 
to 10 CFR Part 50. The following identifies specific provisions of 
Appendix I to 10 CFR Part 50 and 10 CFR Part 20 regulations that may 
need to be reviewed and updated, as warranted:

    Provisions: 4.1: Numerical design objectives of 10 CFR Part 50, 
Appendix I for liquid and gaseous effluents--The revision would 
retain the current numerical dose criteria, but would redefine doses 
as effective dose (ED) or TED for consistency with ICRP Publication 
103 dosimetry concepts in a revised 10 CFR Part 20, or as TEDE with 
the current 10 CFR Part 20 (ICRP Publications 26 and 30) if 10 CFR 
Part 20 were not realigned with ICRP Publication 103. The update 
would necessitate a revision of dose calculation methods described 
in Regulatory Guide 1.109 and associated computer codes.
    4.2: Organ numerical design objectives of 10 CFR Part 50, 
Appendix I for liquid and gaseous effluents--The revision would 
assess whether there is still a need to report doses separately for 
organs since this would not be necessary if ICRP Publication 103 or 
ICRP Publications 26 and 30 were adopted. The assessment would 
consider the provisions of Sections II and III of Appendix I to 10 
CFR Part 50 on doses associated with radioiodine in situations where 
releases might be dominated by the presence of noble gases and 
radioiodine, resulting in potentially significant skin and thyroid 
doses. The assessment would also consider the need to revise the 
scope of thyroid dose contributors to include radionuclides present 
as vapor (tritium) and gases (e.g., 14C in inorganic and organic 
forms) in addition to radioiodine and particulates.
    4.3: Annual gamma and beta air dose for gaseous effluents--The 
gamma and beta dose criteria characterize an absorbed dose rate in 
air, expressed in mrad/year, while the balance of the design 
objectives are expressed in mrem/year for the total body and organs. 
The revision would assess the need to still report gamma and beta 
absorbed air dose results based on a review of historical gaseous 
effluent releases and doses from operating PWR and BWR plants. The 
revision might consider dropping that requirement altogether, or 
alternatively, converting the design objective to an ED or TED dose 
for a receptor assumed to be located at the site boundary.
    4.4: Light-Water-Cooled Reactor Provisions of Appendix I to 10 
CFR Part 50--The revision would consider whether there is a need to 
expand current regulatory provisions for design certifications and 
new reactor applications involving other types of reactor 
technologies. Such new technologies might include new types of 
reactor fuels and modular reactor technologies, e.g., high 
temperature gas-cooled reactors, molten-salt or lead-cooled 
reactors, and breeder reactors.
    4.5: Compliance with Requirements for ``Licensed Operation'' 
under 10 CFR Part 20--The revision would consider the need to expand 
provisions describing compliance requirements for ``licensed 
operation'' for sites with two or more licensed entities 
contributing to and radiation exposures to a single offsite dose 
receptor under Parts 20.1301(a)(1) and 20.1302(a) and (b). The 
expanded provisions would identify acceptable methods in the 
regulation or guidance for apportioning radioactive effluent 
releases and doses between two or more licensed entities. The 
discussion would also consider compliance with EPA regulations of 40 
CFR Part 190 as implemented under 10 CFR Part 20.1301(e).
    Questions: Q4-1: Given the above summary descriptions of the 
provisions of 10 CFR Part 50, Appendix I that might be considered 
for possible revision, should the NRC evaluate all provisions 
described above, or focus instead only on those necessary to align 
10 CFR Part 50, Appendix I regulations with ICRP Publication 103 if 
10 CFR Part 20 were revised, or with ICRP Publication 26 and 30 if 
10 CFR Part 20 were not revised?
    Q4-2: Given the above, are there any significant impacts in the 
implementation of revised 10 CFR Part 50, Appendix I regulations 
that the NRC should consider if it were to proceed with a 
rulemaking?
    Q4-3: If significant impacts in the implementation of revised 10 
CFR Part 50, Appendix I regulations are envisioned, what types of 
issues should the NRC evaluate and consider in revising 10 CFR Part 
50, Appendix I regulations?

    Dated at Rockville, Maryland, this 20th day of September, 2010.

    For the Nuclear Regulatory Commission.
Mark Thaggard,
Deputy Director, Division of Intergovernmental Liaison and Rulemaking, 
Office of Federal and State Materials and Environmental Management 
Program.
[FR Doc. 2010-24137 Filed 9-24-10; 8:45 am]
BILLING CODE 7590-01-P