[Federal Register Volume 66, Number 220 (Wednesday, November 14, 2001)]
[Rules and Regulations]
[Pages 57298-57340]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-28506]
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Part V
Department of Energy
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10 CFR Parts 960 and 963
Office of Civilian Radioactive Waste Management; General Guidelines for
the Recommnedation of Sites for Nuclear Waste Repositories; Yucca
Mountain Site Suitability Guidelines; Final Rule
Federal Register / Vol. 66, No. 220 / Wednesday, November 14, 2001 /
Rules and Regulations
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DEPARTMENT OF ENERGY
10 CFR Parts 960 and 963
[Docket No. RW-RM-99-963]
RIN 1901-AA72
Office of Civilian Radioactive Waste Management; General
Guidelines for the Recommendation of Sites for Nuclear Waste
Repositories; Yucca Mountain Site Suitability Guidelines
AGENCY: Office of Civilian Radioactive Waste Management, Department of
Energy (DOE).
ACTION: Final rule.
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SUMMARY: DOE hereby amends the policies under the Nuclear Waste Policy
Act of 1982 for evaluating the suitability of Yucca Mountain, Nevada,
as a site for development of a nuclear waste repository. Today's final
rule focuses on the criteria and methodology to be used for evaluating
relevant geological and other related aspects of the Yucca Mountain
site. Consistent with longstanding policy to conform DOE suitability
guidelines for its nuclear waste repository program to corresponding
regulations of the Nuclear Regulatory Commission, DOE's criteria and
methodology are based on the Nuclear Regulatory Commission's recently
final regulations for licensing a nuclear waste repository at Yucca
Mountain.
EFFECTIVE DATE: December 14, 2001.
FOR FURTHER INFORMATION CONTACT: Dr. William J. Boyle, U.S. Department
of Energy, Office of Civilian Radioactive Waste Management, Yucca
Mountain Site Characterization Office, P.O. Box 364629, North Las
Vegas, Nevada 89036-8629.
SUPPLEMENTARY INFORMATION:
I. Introduction
II. Background
A. Enactment of the Nuclear Waste Policy Act of 1982
1. Development of the Nuclear Waste Policy Act
2. Overview of the Nuclear Waste Policy Act
B. DOE Promulgation of the General Guidelines at 10 CFR Part 960
1. Overview of the General Guidelines
2. Structure of the General Guidelines
3. Bases for the Structure of the General Guidelines
4. Consistency with NRC Technical and Procedural Conditions
C. DOE Application of the Guidelines
D. 1987 Amendments to NWPA
E. Yucca Mountain Site Characterization Plan
1. Statutory Requirements
2. Structure of the Site Characterization Plan
F. Energy Policy Act of 1992
G. Evolution of the Site Characterization Program
H. The 1993-1995 Public Dialogue on the Guidelines
I. The 1996 Notice of Proposed Rulemaking
J. Proposed NRC Regulation, 10 CFR Part 63
1. Background
2. Structure of Proposed Part 63
K. Proposed EPA Regulation, 40 CFR Part 197
1. Background
2. Structure of Proposed Part 197
L. DOE's 1999 Notice of Proposed Rulemaking
M. Final EPA and NRC Regulations
N. NRC Concurrence
III. Basis for Final Rule
A. Legal Authority and Necessity to Amend the Guidelines and
Criteria
1. Overview
2. Section 112
3. Section 113
B. Events Necessitating Amendment of the Guidelines and Criteria
1. Congressional Redirection of the Program
2. Consistency Between DOE and NRC Regulations
3. Improvements in Analytical Methods
IV. Response to Public Comments on the 1999 Proposal
V. Description of Final Rule--10 CFR Part 960
A. Subpart A--General Provisions
B. Subpart B--Implementation Guidelines
C. Appendix III
VI. Description of Final Rule--10 CFR Part 963
A. Subpart A--General Provisions
B. Subpart B--Site Suitability Determination, Methods and
Criteria
VII. Regulatory Review
A. Review for Compliance with the National Environmental Policy
Act (NEPA)
B. Review under the Regulatory Flexibility Act
C. Review under the Paperwork Reduction Act
D. Review under the Unfunded Mandates Reform Act
E. Review under the Treasury and General Government
Appropriations Act, 1999
F. Review under Executive Order 12866
G. Review under Executive Order 12875
H. Review under Executive Order 12898
I. Review under Executive Order 12988
J. Review under Executive Order 13084
K. Review under Executive Order 13132
L. Review under Executive Order 13211
M. Congressional Notification
I. Introduction
Pursuant to the Nuclear Waste Policy Act of 1982, as amended,
(NWPA), (42 U.S.C. 10101, et seq.), DOE today concludes a rulemaking
which accomplishes two major purposes: (1) Revision of 10 CFR part 960
(``General Guidelines for the Recommendation of Sites for Nuclear Waste
Repositories''); and (2) promulgation of new part 963 (``Yucca Mountain
Site Suitability Guidelines''). The NWPA provides for a multi-stage
siting process including preliminary site screening, site
characterization, DOE site recommendation to the President, and
Presidential approval of a site for the location of nuclear waste
repositories. As originally promulgated in 1984, part 960 governed DOE
activities for comparing and selecting sites from preliminary site
screening to site recommendation. As revised, part 960 is now limited
to preliminary site screening to identify candidates for site
characterization activities (i.e., physical site investigation
activities). Consistent with 1987 amendments to the NWPA, part 963
deals with the criteria for evaluating the suitability of the potential
site at Yucca Mountain, Nevada, based on site characterization
activities, as part of the material that will be considered by the
Secretary in any site recommendation to the President. This rulemaking,
by identifying the types of sound scientific information and methods
that will be used in assessing the likely performance of a repository
at the Yucca Mountain site, sets forth guidance to assist the Secretary
in reaching a judgment on the suitability of that site for a geologic
repository.
DOE began this rulemaking by publishing a notice of proposed
rulemaking on December 16, 1996 (61 FR 66158). That notice attracted
critical comments from members of the public, State and local officials
of Nevada, the U.S. Environmental Protection Agency (EPA), and the U.S.
Nuclear Waste Technical Review Board (NWTRB). In substance, some
comments criticized the omission from the proposed regulations of
essential details of the criteria for determining site suitability.
Other comments questioned the legal basis for the proposal, disputing
DOE's interpretation of sections 112 and 113 of the NWPA. They also
disputed the scientific and technical basis for the proposed
regulations.
On November 30, 1999, DOE published a supplemental notice of
proposed rulemaking that revised the terms of, and its explanation of
the legal and technical basis for, amending its site suitability
criteria to tailor them, as required by law, to the conditions at Yucca
Mountain (64 FR 67054). In explaining its reasons for reproposing, DOE
acknowledged there was enough merit in the comments on its 1996
proposal to warrant issuance of a revised and more detailed proposal
with an expanded explanation of the legal and technical basis for the
proposal. DOE also relied on the implications of its December, 1998,
``Viability
[[Page 57299]]
Assessment of a Repository at Yucca Mountain'' (DOE/RW-0508) (Viability
Assessment), on the EPA's 1999 notice of proposed rulemaking to
establish public health and safety standards for a repository at Yucca
Mountain at new 40 CFR part 197, and on the U.S. Nuclear Regulatory
Commission's (NRC's) 1999 notice of proposed regulatory amendments to
limit its general licensing regulations in 10 CFR part 60 by excluding
the Yucca Mountain site and to promulgate a new part 63 to establish
licensing regulations exclusively for the Yucca Mountain site. On June
13, 2001, the EPA finalized its rulemaking on Yucca Mountain public
health and safety standards (66 FR 32074-32135), followed by the NRC
final rulemaking on November 2, 2001 (66 FR 55732-55816). Neither the
EPA or NRC changed their respective rules from proposed to final form
in any way that materially affects this rulemaking.
In the introductory section of the Supplementary Information
portion of the November 30, 1999, supplemental notice of proposed
rulemaking, DOE stated that it was seeking to improve its policies for
determining site suitability based on site characterization activities
by enhancing their transparency, validity, and verifiability. By
enhancing transparency, DOE means providing informative and readable
regulations, an explanation of the legal and technical basis for the
regulatory amendments, and explanations of complex calculations and
computer modeling that are suitable for non-technical audiences. By
enhancing validity, DOE means providing an explanation of basis and
purpose that clearly shows how the regulatory conclusions followed from
DOE's legal and technical premises. By enhancing verifiability, DOE
means being forthcoming about documented empirical results of
experiments and computer analyses of relevant data so as to allow
verification of conclusions that DOE may eventually draw from known
facts in a supporting statement for a site recommendation to the
President under section 114 of the NWPA.
In response to the supplemental notice of proposed rulemaking, DOE
received a variety of written and oral comments from State and local
officials of Nevada, other Federal agencies, industry sources,
regulatory and oversight organizations, Native American organizations,
and assorted private citizens and citizen groups. While supportive of
much of the content of the proposed regulations, industry sources
argued that the NWPA did not require this rulemaking. Although some
Nevada local officials supported some features of the supplemental
proposal, Nevada State and other local officials continued to take
issue with proposed regulatory provisions and the legal and technical
bases for them. Especially useful were comments about appropriate
arguments to help assess the validity of computer-generated performance
assessment calculations, comments which provided the opportunity for
DOE to underscore provisions in part 963 requiring multiple lines of
argument in backup documentation (eventually to be made available for
public comment) on subjects such as uncertainty, variability of
parameter values, the technical basis for including or excluding
certain features, events, and processes, and the capability of natural
and engineered barriers to isolate radioactive waste.
In DOE's view, this rulemaking is necessary in order to correct the
nonconformity of DOE's prior suitability guidelines to the EPA's and
NRC's current regulatory framework for the licensing of the Yucca
Mountain repository, modified from the prior framework by reason of a
Congressional direction. It has also provided opportunities for State
and local officials and other members of the public to have an impact
on DOE's policymaking process. DOE has provided responses below to the
relevant major issues that emerged from the comments. These responses
appear after sections that substantially repeat portions of the
supplemental notice of proposed rulemaking stating the background,
basis, and purpose of the supplemental proposal. (These sections are
repeated to assist readers who otherwise would have to look back at a
copy of the supplemental notice of proposed rulemaking.) DOE has also
made conforming changes to the rule consistent with final regulations
of the NRC and EPA, and NRC concurrence comments on part 963.
II. Background
This section provides an overview of the developments which have
led DOE to propose to revise certain sections of the existing General
Guidelines for the Recommendation of Sites for Nuclear Waste
Repositories and to adopt a new rule setting out the site suitability
criteria for the Yucca Mountain site.
A. Enactment of the Nuclear Waste Policy Act of 1982
1. Development of the Nuclear Waste Policy Act
The NWPA was enacted to provide for the siting, construction, and
operation of repositories for which there is a reasonable assurance
that the public and the environment will be adequately protected from
the hazards posed by spent nuclear fuel and high-level radioactive
waste (hereinafter referred to as ``spent fuel'' or ``high-level
waste'' or both). The NWPA established the Federal responsibility and
defined Federal policy for the disposal of spent fuel and high-level
waste. Because this waste remains radioactive for many thousands of
years, Congress recognized that disposal involved many complex and
novel technical and societal issues. To develop an appropriate
framework for the resolution of these issues, several years of intense
legislative effort were required before a political consensus emerged
to support enactment of the NWPA.
To meet the well-recognized reluctance of communities to host such
facilities, the NWPA included a national site selection process that
was designed to ensure fairness and objectivity in the identification
of potential candidate sites for a repository. To ensure that the DOE
would consider only candidate sites that had good potential for being
licensed by the NRC, the NWPA required the DOE to obtain NRC
concurrence on the DOE's General Siting Guidelines. And to ensure that
the regulatory requirements for a repository would be set independently
of any responsibility assigned to the DOE to develop that repository,
the EPA was authorized to promulgate generally applicable standards for
the protection of the environment. The NRC was authorized to establish
repository licensing requirements and criteria, although these
requirements and criteria could not be inconsistent with any relevant
public health standards promulgated by the EPA.
2. Overview of the Nuclear Waste Policy Act
As originally enacted in 1982, the NWPA set forth requirements for
selecting sites for the disposal of spent fuel and high-level waste in
a geological repository (42 U.S.C. 10101, et seq.). Several stages were
established for the evaluation of potential sites, and these stages
were defined in section 112, Recommendation of Candidate Sites for Site
Characterization; section 113, Site Characterization; and section 114,
Site Approval and Construction Authorization.
Section 112 of the NWPA addresses the initial stage of the site
selection process, and includes four distinct steps: (1) DOE
preliminary site screening (42 U.S.C. 10132(a)); (2) DOE nomination of
at least five sites as suitable for characterization (42 U.S.C.
10132(b)(1)(A)); (3) DOE
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recommendation to the President of three of the five nominated sites as
candidates for characterization (42 U.S.C. 10132(b)(1)(B)); and (4)
Presidential approval of nominated sites for characterization (42
U.S.C. 10132(c)). Specifically, section 112(a) directed the DOE to
issue General Guidelines for the recommendation of candidate sites for
repositories, and to use the Guidelines in considering sites for site
characterization. Section 112 also directed DOE to consult with several
federal agencies and obtain NRC concurrence on these Guidelines.
Under section 112(a), DOE was required to specify in the
Guidelines: (1) Detailed geologic considerations that were to be the
primary criteria for the selection of sites for characterization in
various geologic media; (2) certain factors (e.g., hydrology,
geophysics, seismic activity) that would either qualify or disqualify a
site from characterization; and (3) population density and distribution
factors that would disqualify any site for characterization (42 U.S.C.
10132(a)). Section 112(a) also required DOE to include certain factors
related to the comparative advantages among candidate sites. DOE was
directed to use the Guidelines to consider candidate sites for
recommendation as candidates for characterization. Section 112(a)
explicitly authorized DOE to modify the Guidelines consistent with the
provisions of section 112(a).
Furthermore, section 112(a) directed DOE to develop certain
qualifying or disqualifying factors for the preliminary site screening
stage of the site selection process. Except for population density, the
specific content of the qualifying or disqualifying factors was left to
DOE's discretion. Because these factors are part of the Guidelines,
their specific content could be modified in accordance with the
authority in section 112(a).
Section 112(b) of the NWPA addressed DOE's recommendation to the
President of sites for site characterization, that is, for intensive
investigation of geologically related characteristics through surface
and subsurface testing, among other investigative techniques. DOE was
to nominate at least five sites as suitable for characterization. Each
nominated site was to be accompanied by an environmental assessment. Of
the five sites, DOE was to recommend three to the President for
characterization. Section 112(c) of the NWPA addressed the President's
review and approval of candidate sites for characterization.
Section 113 of the NWPA addresses site characterization, which
involves activities that could proceed only after the section 112
actions had been completed. Section 113(a) authorizes DOE to conduct
site characterization activities at the sites that had been approved by
the President for characterization. Section 113(b) establishes the
scope of DOE's site characterization activities, and directs the
publication of a general plan for these activities (42 U.S.C.
10133(b)(1)(A)). DOE is to report semiannually on its ongoing and
planned site characterization activities and the information derived
therefrom (42 U.S.C. 10133(b)(3)). Section 113(b) also directs DOE to
include in the site characterization plan criteria to be used to
determine the suitability of a site for the location of a repository,
developed pursuant to section 112(a) (42 U.S.C. 10133(b)(1)(A)(iv)).
Section 113(c) limits DOE's site characterization activities to those
the Secretary considers necessary to provide the data required to
evaluate a site's suitability for an application for a construction
authorization as a repository and to comply with NEPA. It also provides
direction on how DOE is to proceed if at any time it determines that a
site would be unsuitable for development as a repository.
Section 114 addresses site approval and construction authorization.
Four distinct steps are defined in this section: (1) DOE recommendation
of a site to the President for approval to develop as a repository (42
U.S.C. 10134(a)); (2) recommendation of a site by the President to
Congress (42 U.S.C. 10134(a)(2)); (3) Congressional designation of the
site (42 U.S.C. 10135(b)); and (4) conduct of a licensing proceeding by
the NRC (42 U.S.C. 10134(c)). Further, under section 115, after the
President recommends a site to Congress, the Governor and the
legislature of the host State may submit a notice of disapproval. If
the State disapproves, Congress must enact a resolution of siting
approval in order to designate the site (42 U.S.C. 10135(b)). If the
designation takes effect, DOE is to submit an application to the NRC
for a construction authorization within 90 days of the designation's
taking effect. (42 U.S.C. 10134(b)).
Section 114(a) provides for DOE activities preceding the
Secretary's preparation of a recommendation to the President for
Presidential approval of a site for development as a repository. These
activities include public hearings in the vicinity of the site to
inform residents of the area and receive their comments, and the
completion of site characterization. Upon completion of these hearings
and site characterization, the Secretary may decide to recommend the
site to the President. A comprehensive statement of the basis for this
recommendation is to accompany the recommendation, and be made
available to the public (42 U.S.C. 10134(a)(1)). If the President
recommends a site to the Congress and that recommendation is permitted
to take effect, section 114(b) then directs DOE to apply to the NRC for
construction authorization. Sections 114(c)-(e) direct the NRC and DOE
on certain aspects of the construction authorization process. Section
114(f) requires that a final Environmental Impact Statement (EIS)
accompany the Secretary's recommendation of a site to the President.
B. DOE Promulgation of General Guidelines at 10 CFR Part 960
1. Overview of the General Guidelines
Section 112(a) of the NWPA directed DOE to issue General Guidelines
for use in considering and recommending sites for site
characterization, in consultation with certain Federal agencies and
interested Governors, and with the concurrence of the NRC. These
General Guidelines were to be comparative in nature, as DOE was
required to consider various geologic media and such considerations as
proximity to where spent fuel and high-level waste were stored. The
General Guidelines were also to consider non-geologic factors, such as
population density and distribution, that would not be examined in site
characterization. No other requirements were imposed on the issuance of
these Guidelines.
DOE promulgated the section 112(a) Guidelines by notice and comment
rulemaking, in addition to the consultation and concurrence process
specified in the NWPA. The DOE also conducted several public meetings
on the Guidelines. These additional activities, although not required
by the NWPA, enabled DOE to receive comments from interested members of
the public. The General Guidelines were promulgated on December 6,
1984, and codified in the Code of Federal Regulations at 10 CFR part
960, General Guidelines for the Recommendation of Sites for the Nuclear
Waste Repositories. 49 FR 47714.
2. Structure of the General Guidelines
The Guidelines promulgated by DOE defined the basic technical
requirements that candidate sites would be expected to meet, and
specified how DOE would implement its site-selection process. The
Guidelines were structured according to three categories:
Implementation guidelines, preclosure guidelines and postclosure
guidelines.
[[Page 57301]]
The implementation guidelines addressed general application of all the
Guidelines, and established the methodology for applying the Guidelines
during the various stages of the siting process: Site screening and
nomination, recommendation for characterization, and recommendation for
repository development. The preclosure guidelines governed the siting
considerations that dealt with the operation of a geologic repository
before it is closed. The postclosure guidelines governed the siting
considerations that dealt with the long-term behavior of a geologic
repository after waste emplacement and closure.
Both the preclosure and postclosure guidelines were organized under
general categories of interest, for example, geohydrology and
geochemistry. Each category was further divided into system guidelines
and corresponding technical guidelines. The system guidelines addressed
broad requirements for a geologic repository under preclosure and
postclosure conditions; the corresponding technical guidelines
specified conditions that would qualify or disqualify a site, and
conditions that would be considered favorable or potentially adverse.
49 FR 47724. In effect, the technical guidelines and the associated
qualifying and disqualifying conditions imposed specific ``subsystem''
performance requirements; each subsystem requirement would be used to
evaluate the merits of a site, independent of the other requirements.
Section 112 of the NWPA described the minimum steps that DOE was to
take during site screening and prior to site characterization. When
promulgating the Guidelines in 1984, DOE determined that application of
the Guidelines should extend beyond preliminary site screening to
encompass site characterization activities and site recommendation to
the President. Appendix III to the Guidelines explained how certain of
the Guidelines would be applied at the principal decision points of the
siting process: (1) Identification of a site as being potentially
acceptable under section 112(b); (2) nomination and recommendation of
sites as suitable for characterization under sections 112(b) and (c);
and (3) recommendation of a site for development as a repository
(sections 113 and 114). 49 FR 47729-47730. With respect to the third
decision point, which would be reached only after completion of site
characterization activities and non-geologic data gathering activities,
DOE did not promulgate separate guidelines. Instead, DOE indicated that
the preclosure and postclosure guidelines would be applied to this
decision, and appropriate findings issued, in the manner prescribed in
Appendix III. Appendix III specified the types of findings that were to
be issued from the application of the disqualifying and the qualifying
conditions at each of the three decision points. The types of findings
corresponded with the level of confidence required to make a finding;
that is, a lower level finding required one degree of confidence in the
finding, and a higher level finding required an increased level of
confidence in the finding over the lower level. 49 FR 47728-47729.
Appendix III included a table summarizing the level of the finding
required at each of the three decision points.
Appendix III represented the analytical process DOE would follow to
issue findings relative to the disqualifying and qualifying conditions
of a site, and use in its decision-making on site selection. This
analytical process specified a higher-level of confidence in the
findings of qualifying or disqualifying conditions at the last stage of
the siting process, site selection for repository development, compared
to the initial stage of the siting process, site nomination for site
characterization. DOE anticipated that the higher-level of confidence
in its technical findings would be obtained through the site
characterization process undertaken at the later stages of the
selection process.
3. Bases for the Structure of the General Guidelines
The structure and development of the Guidelines were based on four
primary sources of information and considerations: (1) The direction in
the NWPA, as originally enacted; (2) the extant understanding of
geologic disposal in the scientific and technical community; (3)
applicable regulations proposed by the NRC and the EPA governing the
disposal of spent nuclear fuel and high-level radioactive waste in
geologic repositories; and (4) public comments.
DOE initiated the rulemaking process by assembling a task force of
program experts. 49 FR 47718. The task force developed draft Guidelines
based on criteria used earlier in the National Waste Terminal Storage
Program, including program objectives, system performance criteria, and
site performance criteria. At the time, the task force reviewed other
criteria defined for geologic repositories by the National Academy of
Sciences and the International Atomic Energy Agency.
The task force also sought consistency with NRC regulations and
proposed EPA regulations related to geologic repositories. 49 FR 47718.
NRC is the statutory agency responsible for licensing the construction
and operation of a geologic repository; EPA is the statutory agency
responsible for setting public health and safety standards for a
geologic repository. Consistency of the DOE Guidelines with these
regulatory standards was essential, since any potential site would be
evaluated based on its ability to meet applicable regulatory
requirements. 49 FR 47721.
In sum, the structure and content of the Guidelines was based on
the state of knowledge in the late-1970s and early-1980s in the
regulatory community, as well as the national and international
scientific community, regarding the development of geologic
repositories and the regulations promulgated by NRC and EPA to govern
the licensing of a repository.
DOE sought and received extensive public comments on a draft of the
Guidelines before submitting them to the NRC for concurrence. On
February 7, 1983, the proposed Guidelines were published in the Federal
Register (48 FR 5670) for public review and comment. In addition, DOE
published a separate notice soliciting comment from the Governors of
the six States with potentially acceptable sites, and then met
individually with officials from each of these States. DOE also held a
series of regional public hearings. After considering the comments
received, DOE drafted a set of revised guidelines to address the
comments. The revised guidelines and public comments were made
available in a second notice on June 7, 1983 (48 FR 26441), followed by
a second public comment period. Further regional meetings and
consultations with Federal agencies were held before DOE submitted the
final version of the Guidelines to NRC for concurrence on November 22,
1983. 49 FR 47718-47719.
4. Consistency With NRC Technical and Procedural Conditions
Of particular importance to DOE's formulation of the Guidelines was
consistency with NRC licensing regulations for the disposal of waste in
a geologic repository. 49 FR 47718. In June 1983, NRC amended its
licensing regulations at 10 CFR part 60 with respect to subpart E,
technical criteria addressing siting, design and performance objectives
of a geologic repository. 48 FR 28194. NRC concurred in the Guidelines
subject to conditions that would satisfy the overall need to maintain
consistency between NRC regulations and the DOE Guidelines. Among the
NRC conditions were: (1)
[[Page 57302]]
DOE clarifications and deletions of certain limiting terms such as
``permanent'' and ``significant'; (2) DOE modifications for consistency
with NRC criteria regarding anticipated processes and events,
potentially adverse conditions, and the role of engineered barriers
during the process for screening candidate sites for characterization;
and (3) DOE revisions and additions to disqualifying conditions to
ensure that unacceptable sites would be eliminated as early as
practicable. 49 FR 47719-47722.
NRC concurrence conditions also addressed general, procedural
aspects of how the DOE was to apply the Guidelines. For example, NRC
concurrence was conditioned on a lack of conflict between NRC
regulations at 10 CFR part 60 and the Guidelines, recognition by DOE
that NRC regulations were controlling in the event of any differences,
and a commitment that DOE would obtain NRC concurrence on any future
revisions to the Guidelines. 49 FR 47719-47720. NRC also requested DOE
to specify in greater detail how the Guidelines would be applied at
each siting stage. This specificity was provided by the addition of
Appendix III to the Guidelines. Appendix III indicated how the
Guidelines would be applied at all of the site selection stages,
including the recommendations to the President for site
characterization and for the development of a site as a repository.
The NRC required additional changes after it met publicly with
representatives of several interested states, Indian tribes, and DOE.
After DOE committed to making those changes, the NRC voted to concur in
the Guidelines. 49 FR 47720. Thus, the part 960 Guidelines took account
of the substantial input provided by the NRC in 1984 through the
statutory concurrence process.
C. DOE Application of the Guidelines
Consistent with section 112(b) of the NWPA, DOE applied the
Guidelines to: (1) nominate five sites as suitable for
characterization; and (2) recommend to the President three of those
five nominated sites for characterization as candidate sites for the
first repository. On May 27, 1986, the President approved each of the
sites that had been recommended for characterization. Yucca Mountain
was one of the three sites that DOE recommended. The recommendation to
the President was documented in a DOE report, Recommendation by the
Secretary of Energy for Site Characterization for the First
Radioactive-Waste Repository (May 1986; DOE/S-0048). In addition, a
draft environmental assessment was prepared for each of the five sites
and final environmental assessments were prepared for each of the three
sites that were recommended.
This action concluded the process that had been established by the
NWPA for identifying sites for characterization. The Guidelines' role
of structuring DOE's process for identifying sites for characterization
was completed in accordance with the Congressional directives to DOE.
Under DOE's formulation of the Guidelines at that time, however, the
Guidelines would remain relevant and applicable through the third
principal siting decision point, the selection of a site to be
recommended for the development of a repository.
D. 1987 Amendments to NWPA
In 1987, Congress amended the NWPA to mandate Yucca Mountain as the
sole site to be characterized (42 U.S.C. 10172 (Supp. V 1987)). The
processes for site characterization under section 113 and site approval
under section 114 were made applicable to only Yucca Mountain. Under
sections 113(a) and (b), Yucca Mountain was designated as the site for
which site characterization activities would take place, and a site
characterization plan would be issued, respectively. Under section
113(c), Congress amended the statute to name Yucca Mountain as the site
for which the restrictions on site characterization activities would be
applicable. That is, DOE was directed to conduct only such activities
at Yucca Mountain that are necessary to evaluate the suitability of the
site for an application to the NRC for a construction authorization,
and to comply with requirements under the National Environmental Policy
Act (NEPA). Section 114 was amended to excuse DOE from analysis of
alternative sites in any environmental impact statement (EIS) that may
be prepared for the Yucca Mountain site under NEPA. Any such EIS would
analyze the Yucca Mountain site, and no other sites, for potential
development of a geologic repository. Further, section 160(b) directed
DOE to ``terminate all site specific activities (other than reclamation
activities) at all candidate sites, other than the Yucca Mountain
site.'' (42 U.S.C. 10172(a)(2)).
In sum, Congress made clear its intent for DOE to focus its
resources on investigating only Yucca Mountain as a potential site for
a high-level radioactive waste repository.
E. Yucca Mountain Site Characterization Plan
1. Statutory Requirements
Under sections 113 and 160 of the NWPA, as amended, DOE was
directed to conduct site characterization activities at the Yucca
Mountain site. Prior to initiating site characterization under section
113, DOE was required to prepare a general plan for site
characterization activities at the Yucca Mountain site. DOE was
required to submit the plan to the NRC and the State of Nevada for
their review and comment (42 U.S.C. 10133(b)(1)), as well as to members
of the public in the vicinity of Yucca Mountain (42 U.S.C.
10133(b)(2)). Certain contents of the plan were mandated by section
113(b), including, among other things, a description of planned
excavation and other testing activities, a description of the possible
form or packaging of the high-level waste, and the criteria to be used
to determine the suitability of the site for the location of a
repository, developed pursuant to section 112(a). Section 113(b)(3)
also required DOE to report every six months on the progress of site
characterization activities at Yucca Mountain, and to provide the
reports to the NRC, and the Governor and the legislature of the State
of Nevada.
DOE prepared the site characterization plan in draft form in
January 1988. In preparing the plan, DOE generally followed NRC
guidance, as specified in the document, Standard Format and Content of
Site Characterization Plans for High Level Waste Geologic Repositories,
Regulatory Guide 4.17 (NRC 1987). After review and comment by NRC, the
State of Nevada, and interested members of the public, DOE finalized
the Site Characterization Plan: Yucca Mountain Site, Nevada Research
and Development Area, Nevada (December 1988; DOE/RW-0198) (hereinafter
also the SCP), in December 1988.
2. Structure of the Site Characterization Plan
``Site characterization'' is defined in the NWPA to include
research activities undertaken to establish the geologic condition of a
site, for example, borings and surface excavations, and in situ testing
necessary to evaluate the suitability of a candidate site for the
location of a repository (42 U.S.C. 10101(21)). In the SCP, DOE
described the purpose of its site characterization program at Yucca
Mountain as to obtain the information necessary to determine whether or
not the site is suitable for a repository, and could satisfy NRC
[[Page 57303]]
licensing requirements (which must be consistent with EPA public health
and safety standards). DOE also explained there that the information
obtained from site characterization, such as the geologic,
geoengineering, hydrologic, and climatological conditions at a site,
would be used to develop and optimize repository design and to evaluate
the performance of the site and the engineered barriers as an
integrated system.
The purpose of the SCP was threefold: (1) To describe the site, and
the preliminary designs for the repository and the waste packages in
sufficient detail to form the basis for the site characterization
program; (2) to identify issues to be resolved during site
characterization and present the strategy for resolving the issues; and
(3) to describe the plans for the work needed to obtain the information
deemed necessary and to resolve outstanding issues. The SCP was
organized along two lines: (1) An issues hierarchy, which embodied the
DOE, NRC and EPA regulations governing the repository system; and (2)
an issue-resolution strategy.
The issues hierarchy was a three-tiered framework laying out what
must be known before the Yucca Mountain site could be selected and
licensed. ``Issues'' were defined as questions related to performance
of the repository that must be resolved to demonstrate compliance with
applicable regulations of DOE, NRC and EPA. DOE identified four key
issues to be addressed, based on regulatory requirements and the four
system guidelines in part 960: (1) Postclosure performance; (2)
preclosure performance; (3) environment, socioeconomic, and
transportation impacts of a repository; and (4) ease and cost of
repository siting, construction, operation and closure. DOE also
explained that only the first, second, and part of the fourth key issue
would be addressed in the site characterization program, since
resolution of these other key issues (that is, key issue 3 and part of
key issue 4) were not dependent on information from site
characterization activities. The issue-resolution strategy consisted of
four parts: issue identification, performance allocation, data
collection and analysis, and documentation of issue resolution. This
framework was used to develop test programs and explain why the test
programs were adequate and necessary. The object was to collect
information to be used in a concluding set of analyses to resolve the
issues, and to document resolution of the issues.
As required by section 113(b)(1)(A)(iv), the SCP included criteria
to determine the suitability of the site for development of a
repository. Those ``criteria'' were the provisions within the
Guidelines pertinent to site characterization activities, namely, the
postclosure guidelines, and the preclosure guidelines related to
radiological safety and technical feasibility of repository siting,
construction and operation, to be applied in the manner described in
Appendix III. Appendix III set out the level of findings DOE would make
relative to the system and technical requirements found in the
postclosure guidelines (subpart C) and preclosure guidelines (subpart
D) at the final decision point of recommending a site for development
as a repository. DOE believed that the information gained through site
characterization and the issue resolution process would form the basis
for these findings.
DOE also explained in the SCP that not all of the Guidelines would
be addressed as part of site characterization activities. The SCP would
not address the environmental, socioeconomic and transportation
guidelines, or certain guidelines related to ease and cost of
repository siting, construction, operation, and closure, since DOE
would not develop information related to those guidelines through site
characterization activities. Those Guidelines would be addressed in
other investigations and plans to be conducted concurrently with the
site characterization program. Also, in light of the 1987 amendments to
the NWPA permitting site characterization to proceed only at Yucca
Mountain, DOE stated in the SCP that the comparative portions of the
Guidelines would not be applied in the site suitability determination
to be made under section 113(b).
In accordance with section 113(b)(3), approximately every six
months DOE has issued a report updating information on the conduct of
site characterization activities at the Yucca Mountain site. Those
reports briefly summarize the characterization activities undertaken at
the site, the technical and scientific issues of key interest and their
resolution, and issues that remain for further characterization and
resolution. In addition, the semiannual reports provide references and
a bibliography of other reports and documents containing more detailed
information regarding site characterization activities. DOE has been
providing the reports to the NRC, the Governor of Nevada, and the
legislature of the State of Nevada.
The progress reports also reflect DOE's ongoing interaction with
the NRC. In July 1986, the NRC amended its regulations at 10 CFR part
60 (51 FR 27158) to establish the method of interaction between DOE and
the NRC on the development and implementation of the site
characterization plan. NRC established a system for DOE to report on
the results of site characterization, identify issues, plan for
additional studies, eliminate planned studies no longer necessary, and
identify decision points reached. In this manner, the NRC established a
clear pathway to interact with DOE in the management and direction of
the site characterization program.
Site characterization activities have continued up to and including
the present, and are described in greater detail below in section II.G.
F. Energy Policy Act of 1992
In 1992, Congress enacted certain provisions in the Energy Policy
Act of 1992 (Pub. L. No. 102-486) affecting the nation's nuclear waste
repository program. In section 801(a) of the Energy Policy Act of 1992
(EPACT), Congress directed EPA to promulgate a new, health-based
standard to ensure protection of the public health from high-level
radioactive waste that may be disposed in a geologic repository located
at Yucca Mountain. The new standard could depart from the generic EPA
standards promulgated at 40 CFR part 191, and would be specific to
Yucca Mountain. In section 801(b), Congress also directed the NRC,
within one year of EPA's adopting a new standard, to modify its
technical requirements and criteria under section 121(b) of the NWPA
(42 U.S.C. 10141(b)) (i.e., 10 CFR part 60), as necessary, to be
consistent with the new EPA standard.
Before setting the new standard, however, EPA was required to
contract with the National Academy of Sciences (NAS) to conduct a study
to provide findings and recommendations on reasonable standards for
protection of the public health and safety. Under section 801(a) of the
EPACT, EPA was required to promulgate its new standards based on, and
consistent with, the NAS findings and recommendations. Under the EPACT
and accompanying congressional instruction, NAS's charge was to answer
three specific questions embodied in section 801(a)(2), and to advise
EPA on the technical basis for the health-based standards it was
mandated to prepare. The three questions posed in section 801(a)(2)
addressed: (1) Whether or not a health-based standard based on doses to
individual members of the public would provide a reasonable basis for
[[Page 57304]]
protecting public health and safety; (2) whether or not it is
reasonable to assume that a system for postclosure oversight of the
repository, using active institutional controls, will prevent an
unreasonable risk of breaching the repository's engineered or natural
barriers, or of increasing the exposure of individual members of the
public to radiation beyond allowable limits; and (3) whether or not it
is possible to make scientifically supportable predictions of the
probability that the repository's engineered or natural barriers will
be breached as a result of human intrusion over a period of 10,000
years.
In August 1995, NAS published the statutorily mandated report,
entitled Technical Bases for Yucca Mountain Standards. In sum, NAS
issued findings that: (1) A health standard for Yucca Mountain based on
risk to individuals of adverse health effects from releases from the
repository (rather than EPA's generic standards which contain both
individual dose and release limits) was an appropriate standard that
would adequately protect the health and safety of the general public;
(2) it is not reasonable to assume that a system for postclosure
oversight can be developed, based on active institutional controls,
which will itself prevent an unreasonable risk of breaching the
repository's engineered barriers or of increasing the exposure of
individual members of the public to radiation beyond allowable limits;
and (3) it is not possible to make scientifically supportable
predictions of the probability that a repository's engineered or
geologic barriers will be breached as a result of human intrusion over
a period of 10,000 years. Notwithstanding the latter two findings, the
NAS recommended EPA include in its standards a stylized human intrusion
event. The NAS reasoned that such an analysis may provide useful
insight into the degree to which the ability of a repository to protect
the public health and safety would be degraded by an intrusion.
In reaching its findings and recommendations, the NAS consulted
with numerous entities, including local, state and federal government
agencies, private organizations, and scientists and engineers, both
national and international, familiar with the technical issues under
study, and held five open technical meetings to ensure a thorough
review of the scientific literature on the subject. In the Technical
Bases for Yucca Mountain Standards, the NAS provided a detailed
explanation of the assumptions and analyses underlying the study, and
the reasons for NAS's findings and recommendations. Among the more
important of these is the NAS assumption, confirmed by its technical
review, that it is possible to conduct scientifically justifiable
analyses of repository behavior over thousands of years in order to
assess whether or not a repository can comply with the applicable
public health standard. In addition, based on its analyses, the NAS
concluded that the proper way to evaluate the risks of adverse health
effects, and to compare those risks to the proposed standard, is to
assess the estimated potential future behavior of the entire repository
system and its potential effect on humans. The procedure used to
perform this analysis is called total system performance assessment
(alternately called performance assessment).
In discussing the possible implications of its conclusions, the NAS
noted that, if EPA issued standards based on individual risk (as
recommended by the NAS), then the NRC would be required to revise its
regulations embodied in 10 CFR part 60 to be consistent with EPA. This
is because NRC's 10 CFR part 60 is directed in part to subsystem
technical requirements, whereas the NAS concluded that it is the
performance of the total system, rather than that of its individual
elements in isolation, that is crucial in the context of a risk-based
standard. Under a risk-based standard, imposing subsystem performance
requirements might result in a deficient repository design even if each
subsystem element meets or exceeds a certain performance standard. The
NAS also observed that its recommendations, if adopted, implied the
development by EPA of different regulatory and analytical approaches
from those employed in the past, and that the process of establishing
the new standards would require significant time and opportunity for
public comment and review. Nevertheless, NAS noted that these potential
changes should not impede site characterization work by DOE at Yucca
Mountain.
G. Evolution of the Site Characterization Program
Since publication of the SCP in 1988, DOE's site characterization
program at Yucca Mountain has made substantial progress in developing
information and data about the site and resolving outstanding technical
issues. Over time, the site characterization program has evolved and
been driven by advances in science and technology, as well as
legislative and managerial changes. The following summarizes the
evolution and status of the site characterization program.
Technical Components of the Site Characterization Program. The
three main technical components of the site characterization program
are testing, design, and performance assessment. Testing encompasses
the investigation of natural features and processes at the site through
field testing, conducted above and below ground, and laboratory testing
of rock and water samples. Design refers to work on development of the
description of a repository and waste packages tailored to the site
features, supported by laboratory testing of candidate materials for
waste packages and design-related testing in underground tunnels
similar to those in which waste would be emplaced. Performance
assessment refers to the quantitative estimates of the performance of
the total repository system, over a range of possible conditions and
for different repository configurations, by means of computer modeling
techniques that are based on site and materials testing data and
accepted principles of physics and chemistry.
Through the testing program, DOE has learned a great deal about the
geologic conditions of the site. The single largest effort undertaken
in this regard has been construction of the Exploratory Studies
Facility (ESF). Construction of this facility began in 1992 and was
completed in 1998. The ESF, a 4.9 mile long underground tunnel, has
enabled DOE to conduct testing and exploration activities in Yucca
Mountain at the depth of the proposed repository. Utilization of this
facility has formed the basis for increased knowledge and understanding
of the mechanical and hydrologic characteristics of the geologic
formation in which the repository would be constructed. Ongoing work at
this facility will focus primarily on thermal and hydrologic testing in
the cross drift to extend and, where necessary, modify this
understanding of the properties of the host rock.
The design component of the site characterization program comprises
those activities aimed at developing concepts for the engineered
components of the geologic repository. Design activities use
information about the site gained through the testing program, and
information about the engineered barrier system gained through other
scientific investigations, to generate and develop design concepts that
can meet the requirements placed on the engineered components of the
repository. Site characterization activities are structured to acquire
data needed to support the
[[Page 57305]]
design. For example, a number of the site characterization program
tests focus on the hydrological, geomechanical and thermal properties
of Yucca Mountain. These tests are significant because they provide the
fundamental information needed to specify the approach to be used in
developing the geologic repository thermal loading and underground
support schemes. Also, under the design program, DOE examines various
approaches to meeting engineered facility requirements, and conducts
comparative evaluations of the costs and benefits of different
approaches to developing design concepts.
The performance assessment component of site characterization
represents the analytical method (i.e., computer modeling) DOE uses to
forecast the performance of the repository within the Yucca Mountain
setting and assess that performance against regulatory standards. Put
in simplified terms, performance assessment uses the information and
data collected under the testing and design programs to feed computer
models that describe how the site would behave in the presence of a
repository and how the engineered system would behave within the
environmental setting of the mountain. Each model, called a process
model, is designed to describe the behavior of individual and coupled
physical and chemical processes. A total system performance assessment
(TSPA) links the results of individual process models to construct a
computer model of the repository system and surrounding environment
that are important to assessment of overall repository performance.
With the TSPA model, DOE can estimate releases of radionuclides from a
repository under a range of conditions, over thousands of years, and
forecast the consequent probable doses to persons.
Performance assessment (or TSPA), as described above, is an
accepted method to assess the performance of a repository at Yucca
Mountain. DOE's use of performance assessment models began even before
issuance of the SCP in 1988. Since that time, however, significant
advancements have been made in the technical capability, acceptance,
and use of this analytical tool. In 1991, the Nuclear Energy Agency
Radioactive Waste Management Committee and the International Atomic
Energy Agency International Radioactive Waste Management Advisory
Committee confirmed that TSPA provides an adequate means to evaluate
long-term radiological impacts of a waste disposal system. On a
national level, the NRC, the NAS and the Nuclear Waste Technical Review
Board (``NWTRB'') (a Congressionally mandated committee of experts
chartered to evaluate the technical and scientific validity of
activities undertaken by DOE to characterize Yucca Mountain to
determine its suitability as a location for a repository) have
acknowledged the value of this method for evaluating postclosure
performance for a repository at Yucca Mountain.
A significant portion of the DOE site characterization program has
been aimed at developing the scientific bases that serve as the
foundation for the process models used in performance assessment. DOE
developed performance assessment models and conducted benchmark
performance assessments of the total repository system in 1991, 1993
and 1995. Between these benchmark assessments, DOE conducted many
performance assessments to evaluate selected features of the site and
the evolving design. DOE used these total system and subsystem
performance assessments to evaluate design options and to determine
further data needed from site investigations. Another TSPA was
conducted in 1998, the results of which are contained in the Viability
Assessment.
Redirection of the Site Characterization Program. In 1994, DOE
conducted extensive internal and external reviews of the program. As a
result of those reviews, documented in the Civilian Radioactive Waste
Management Program Plan (December 1994; DOE/RW-0458) (Program Plan),
DOE identified cost-cutting measures to reduce the cost of completing
site characterization. In response to Congressional concern about the
1994 Program Plan, DOE submitted a revised Program Plan to Congress
that was designed to maintain scientific investigations at the site and
retain target dates for determining site suitability and recommendation
for construction authorization. Civilian Radioactive Waste Management
Program Plan, Revision 1 (May 1996; DOE/RW-0458). As part of the
revised strategy, DOE redirected project efforts to address the major
unresolved technical questions and to complete an assessment of the
viability of licensing and constructing a repository at Yucca Mountain.
Congress indicated its approval of the revised Program Plan in the
Conference Report on the Energy and Water Development Appropriations
Act, 1997, H.R. Rep. No. 782, 104th Cong., 2d Sess. 82 (1996), by
directing that the appropriated funds be used in accordance with the
revised Program Plan issued by DOE in May 1996.
In the Fiscal Year 1997 Energy and Water Development Appropriations
Act (Pub. L. No. 104-206) (referenced above), Congress directed DOE to
provide the viability assessment of the Yucca Mountain site, referenced
in DOE's revised Program Plan, to Congress and the President as a basis
for making future decisions on program funding and direction. DOE
issued the Viability Assessment in December 1998. Drawing on 15 years
of scientific investigation and design work, the Viability Assessment
summarized a large technical basis of field investigations, laboratory
tests, models, analyses and engineering. The Viability Assessment also
identified major uncertainties relevant to the technical defensibility
of DOE's analyses and designs, the approach to managing these
uncertainties, and the status of work relative to the target dates of
2001 for a determination on recommendation of Yucca Mountain and 2002
for submittal of a license application to NRC. The Viability Assessment
also included an iteration of the TSPA conducted in 1998, and the
results of that process.
Coordination with NRC. DOE's implementation of its site
characterization program and the issue resolution strategy embodied in
the SCP has been conducted in close coordination with the NRC. In 1995,
the NRC revised its prelicensing repository program as a result of
changes in the DOE civilian radioactive waste management program, the
findings of the NAS committee recommending changes to the public health
standard for a potential Yucca Mountain repository, and budgetary
constraints imposed by Congress. The NRC adjusted the scope of its
program to focus only on those topics most critical to repository
performance, termed ``key technical issues.'' These issues were
intended to be a vehicle to communicate to DOE those technical matters
for which the NRC had remaining unanswered questions regarding the
performance of the Yucca Mountain site, or the data needed to assess
that performance. DOE's management of the site characterization program
has included activities to obtain information to address the NRC key
technical issues. DOE has structured the site characterization program
in such a manner that one of its goals is for DOE and NRC to reach
consensus that the remaining key technical issues have been addressed
adequately, or that adequate plans are in place to address the issues.
[[Page 57306]]
H. The 1993-1995 Public Dialogue on the Guidelines
In the SCP, issued in December 1988, DOE described how it would
apply the part 960 Guidelines as part of the site characterization
program to evaluate the suitability of the site. DOE indicated in the
SCP that the Guidelines related to site characterization activities
would be applied as the suitability criteria. DOE also indicated there
that the comparative provisions of those requirements would not be
applied in light of the 1987 amendments to the NWPA limiting site
characterization activities to Yucca Mountain. Notwithstanding this
explanation, a number of interested parties suggested it remained
unclear how DOE would apply the Guidelines in the future. Because of
this continuing stated uncertainty, the DOE instituted an ongoing
dialogue with external parties on the Guidelines.
In October 1993, DOE briefed the representatives of the affected
units of local government and the State of Nevada on its plans for
activities related to site suitability evaluation. DOE followed this
briefing with a Notice of Inquiry in the Federal Register (59 FR
19680), dated April 25, 1994, eliciting the views of the public on the
appropriate role of the Guidelines. A public meeting was held on May
21, 1994 in Las Vegas, Nevada. The purposes of the meeting were to
follow-up on a previous public meeting held in August 1993; to update
the public on site characterization activities; and to provide an
opportunity to discuss the development of a process to evaluate site
suitability. DOE then published a second Federal Register notice (59 FR
39766) on August 4, 1994, announcing that it intended to use the
Guidelines as currently written, subject to the programmatic
reconfiguration directed in the 1987 NWPA amendments. Through that
notice, DOE also announced the availability of a draft description of
the proposed process and its intention to hold two additional public
meetings to discuss the matter. Although several options were
discussed, DOE discerned no clearly preferred option from this public
comment process. In response to public comments at the meetings, DOE
committed to provide background information and its rationale for
maintaining the use of the Guidelines as originally promulgated, with
modification to eliminate application of the comparative portions of
the Guidelines. In September 1995, DOE published in the Federal
Register the background information and its rationale, as committed to
in previous public meetings. 60 FR 47737.
In the September 1995 public notice, DOE explained that amending
the Guidelines, either to remove those portions that are primarily used
for comparative purposes or to develop Guidelines tailored to
evaluation of the suitability of the Yucca Mountain site, was not
required at that time. DOE recognized then that the Guidelines might
have to be amended at some future date to be consistent with any
changes to EPA or NRC requirements. 60 FR 47740. Among the options
considered in the 1993-1995 public dialogue was abandonment of the
Guidelines and adoption of the NRC siting criteria in 10 CFR 60.122.
DOE noted that the Guidelines were expressly derived from, and tied to,
the part 60 siting criteria. In addition, DOE noted that, should any
differences between 10 CFR part 960 and 10 CFR part 60 be identified,
10 CFR part 60 would prevail in the licensing process. While
recognizing that much of 10 CFR part 960 subpart B, the implementation
guidelines, was no longer applicable, DOE concluded that the Guidelines
could be selectively interpreted to avoid the comparative aspects while
applying the relevant provisions of subparts C and D, the postclosure
and preclosure guidelines.
I. The 1996 Notice of Proposed Rulemaking
For many of the reasons described earlier in this notice, including
changes in congressional direction of the repository program and
advancements in site characterization, on December 16, 1996, DOE
published in the Federal Register a notice of proposed rulemaking for
10 CFR 960.61 FR 66158. In that notice, DOE proposed to clarify and
focus the Guidelines and to add a new, site-specific subpart E to the
Guidelines. Subpart E would apply only to the Yucca Mountain site, and
would contain preclosure and postclosure system guidelines, each with a
single qualifying condition. 61 FR 66163. In each of the periods, the
qualifying condition would be that a repository at Yucca Mountain be
capable of limiting radiological releases within applicable standards
to be set by EPA and implemented by the NRC through the repository
licensing process. DOE would demonstrate this capability through
performance assessments. 61 FR 66164. These performance assessments
would forecast the performance of a proposed geologic repository at
Yucca Mountain and compare the results of the assessments to the
applicable regulatory standards to determine whether or not the site
would be suitable for development as a repository.
The 1996 proposal was consistent with the system-level evaluation
originally envisioned for the conclusion of site characterization. DOE
recognized in 1984 in the Guidelines that, only after the entire
process of narrowing the number of potentially acceptable sites to one
and after site characterization, would it be possible to conduct
complete performance assessments. Such assessments require detailed
information that can be obtained only during site characterization. 49
FR 47717. In addition, the 1996 proposal was consistent with DOE's
longstanding position that the Guidelines must complement and not
conflict with EPA and NRC regulations, since the ability to meet
applicable public health and safety standards and develop information
adequate to support a license application has always been central to
the site suitability determination.
The 1996 proposal attracted a wide variety of comments from members
of the public, the NRC, the EPA, and the Nuclear Waste Technical Review
Board. The major issues that emerged from the public comment process
were discussed in detail in the Supplementary Information to the
supplemental notice of proposed rulemaking, issued on November 30, 1999
(discussed below at section L).
J. Proposed NRC Regulation, 10 CFR Part 63
1. Background
On February 22, 1999, the NRC published in the Federal Register a
proposed new rule, 10 CFR part 63, containing licensing criteria for
disposal of spent nuclear fuel and high-level radioactive waste in the
proposed geologic repository at Yucca Mountain, along with proposed
revisions to 10 CFR part 60 and other related regulations. 64 FR 8640.
The proposed licensing criteria at part 63 apply exclusively to Yucca
Mountain; part 60 is revised to limit its applicability to geologic
repositories other than one at Yucca Mountain. NRC's proposal seeks to
establish a new system of risk-informed, performance-based regulation.
Under this approach, risk insights, engineering analysis and judgment,
and performance history are used to: (1) Focus attention on the most
important activities; (2) establish objective criteria based upon risk
insights for evaluating performance; (3) develop measurable or
calculable parameters for monitoring system and licensee performance;
(4) provide flexibility to determine how
[[Page 57307]]
performance criteria are met; and (5) focus on results as the primary
basis for regulatory decision-making. 64 FR 8643.
The NRC's rationale for proposing part 63 stemmed from the
requirements of the EPACT. 64 FR 8641-8643. Section 801(b) of EPACT
required that, within one year after EPA promulgates its new standards
for protection of public health and safety, the NRC modify its
technical requirements and criteria for repository licensing (i.e.,
part 60) to be consistent with the new EPA standards. In addition, the
EPACT requires NRC to include in its modifications, consistent with the
NAS findings and recommendations, certain assumptions that are
specified in the EPACT with regard to the effectiveness of DOE's
postclosure oversight of the repository.
As noted above, the NAS issued its findings and recommendations in
the report, Technical Bases for Yucca Mountain Standards, August 1995.
The NAS findings and recommendations reported there, along with
consultation NRC had with EPA, provided the basis for NRC's proposed
modifications. 64 FR 8641, 8643. The NAS' recommended approach to
setting a public health and safety standard has a different objective
from the NRC approach reflected in the pre-existing part 60
requirements and criteria. 64 FR 8643. Accordingly, the modifications
proposed by the NRC, based on the NAS report, and the subsequently
proposed EPA rule marked a change in methodology and licensing
philosophy.
The NRC has now promulgated part 63 in final form. The final
version closely resembles the proposed rule, however the final rule and
changes made by the NRC to the proposed rule are discussed below at
section II. M. Accordingly, we retain the discussion of the proposed
version here, in order to facilitate an understanding of the
development of part 963 by adhering to the chronological narrative of
relevant events.
2. Structure of Proposed Part 63
Preclosure Requirements. In order to obtain a license to construct,
operate and close a repository at Yucca Mountain, proposed part 63
would require DOE to demonstrate compliance with the applicable
preclosure regulatory standards by the use of an integrated safety
analysis. 64 FR 8652. An integrated safety analysis is a systematic
examination of the geologic repository operations area's hazards and
their potential for initiating events (for example, accidents), the
potential consequences of the events, and the site, structures,
systems, components, equipment and activities of personnel. The
analysis would be conducted to ensure that all relevant hazards that
could result in unacceptable consequences have been adequately
evaluated and appropriate protective measures have been identified.
``Integrated'' means joint consideration of safety measures that
otherwise might conflict, including such measures as fire protection,
radiation safety, criticality safety, and chemical safety. The results
of the analysis would be used to support a finding of compliance with a
performance objective for the preclosure period of limiting radiation
exposures and releases within a dose limit of 25 millirem (mrem) to any
member of the public beyond the site boundary.
Postclosure Requirements. In order to obtain a license to
construct, operate and close a repository at Yucca Mountain, proposed
part 63 would require DOE to demonstrate compliance with the applicable
postclosure regulatory standards by the use of a performance assessment
of the potential repository. It should be noted that, in this regard,
while certain parts of proposed part 63 are similar to part 60, in
particular with respect to many procedural and administrative
regulations, this part of the proposed rule, that is, the regulations
governing postclosure performance objectives, is fundamentally
different. The part 60 technical criteria for postclosure relied on
several quantitative, subsystem performance objectives. In 1983-4, NRC
believed this approach was best suited to meet its statutory
requirement under section 121(b)(1)(B) of the NWPA to prescribe
criteria that would involve use of a system of multiple barriers in the
design of the repository. 64 FR 8648. At the time part 60 was written,
NRC's technical opinion was that compliance with this requirement could
be best demonstrated by specifying subsystem technical requirements,
thereby assuring multiple, independent and redundant systems and
barriers. Given advancements in technical understanding and analytical
capability, and information acquired through site-characterization at
Yucca Mountain, the NRC no longer believes this approach is an optimal
and reliable approach to assure compliance with public health and
safety standards. 64 FR 8648-8649.
Accordingly, in its criteria for postclosure system performance and
method for evaluating compliance with those criteria, part 63 does not
contain subsystem performance requirements, or analogs for those
requirements, as found in part 60. The part 63 requirements are based
on only one quantitative standard--demonstrating compliance with an
individual dose limit. The part 63 technical criteria are compatible
with the NRC's current philosophy of risk-informed, performance-based
regulation. This approach is consistent with NAS recommendations that
would require compliance with a health-based standard as the only
quantitative standard for postclosure repository performance. 64 FR
8643. NRC's final rule conforms its approach on this question to EPA's,
and DOE's final guidelines accordingly do likewise.
This approach is also consistent with the NWPA's directive to NRC
in section 121(b)(1)(B) to provide use of a multiple barrier system
(i.e., consisting of both natural and engineered barriers) in the
design of the repository. This objective is attained by requiring DOE
to demonstrate that the natural barriers and the engineered barriers
will work in combination to enhance overall performance of the
repository.
Proposed part 63 would require DOE to demonstrate compliance with
the applicable postclosure regulatory standard by the use of
performance assessment. 64 FR 8650. Performance assessment is a
systematic analysis that identifies the features, events, and processes
that might affect performance of the geologic repository, examines
their effects on performance, and estimates the resulting expected
annual dose. Demonstrating compliance with the postclosure performance
of 10 CFR part 63 would require a performance assessment to
quantitatively estimate the expected annual dose, over the compliance
period, to the average member of a critical group. The critical group
would be a hypothetical group of individuals reasonably expected to
receive the greatest exposure to radioactive materials released from
the geologic repository. Consistent with the EPACT and the 1995 NAS
report, the NRC proposed that the results of the performance assessment
be the sole quantitative measure used to demonstrate compliance with
the individual dose limit. 64 FR 8650.
Because of the importance of the performance assessment, proposed
part 63 was structured to establish certain minimum requirements
governing the content and validation methods for the performance
assessment. 64 FR 8650-8651. For example, DOE would be required to
include in the performance assessment data related to the geology,
hydrology and geochemistry of Yucca Mountain, as well as data related
to the design of the engineered barrier system; to account for
uncertainties and variabilities in the data used to model performance
of the repository; to provide the technical basis for either
[[Page 57308]]
inclusion or exclusion of specific features, events, and processes of
the geologic setting; and to provide the technical basis for the models
used in the overall performance assessment by providing, for example,
comparisons of the output of detailed process-level models and
empirical observations. In addition, proposed part 63 would prescribe
the characteristics of the reference biosphere and receptor to be used
in the performance assessment. DOE also would be required to conduct a
separate performance assessment based on a limited human intrusion
scenario prescribed by the NRC.
K. Proposed EPA Regulation, 40 CFR Part 197
1. Background
On August 27, 1999, the EPA published in the Federal Register a
proposed new rule, 40 CFR part 197, to establish public health and
safety standards governing the storage and disposal of spent nuclear
fuel and high level waste in a potential repository at Yucca Mountain,
Nevada. 64 FR 46975. EPA promulgated this rulemaking pursuant to
section 801(a) of the EPACT. As explained earlier in this preamble
(section I.F.), in section 801(a)(1) of the EPACT Congress directed EPA
to promulgate a health-based standard for the protection of the public
from releases from radioactive materials stored or disposed of in a
repository at the Yucca Mountain site. Also under EPACT, Congress
directed that the EPA standard was to be the only standard applicable
to the Yucca Mountain site, and that the EPA standard must be based
upon and consistent with NAS'' findings and recommendations. 64 FR
46977.
As directed by Congress in the EPACT, it is EPA's role to establish
the public health and safety standard, and NRC's role to implement that
standard in any licensing process NRC may conduct for a repository at
Yucca Mountain. It was therefore anticipated that NRC would conform its
proposed licensing regulation at 10 CFR part 63 to the final EPA
radiation protection standards, as necessary and appropriate. EPA has
now promulgated its final standards as is discussed below in section
II. M. 66 FR 32074. NRC's final part 63 contains modifications from its
proposal necessary to make conforming changes. The NRC final rule and
EPA's final standards closely resemble the standards as proposed.
Changes are discussed at section II. M. below, but as in the case of
the NRC rule, we likewise retain our discussion of the proposed EPA
rule here on the ground that this chronological approach best advances
understanding of the development of DOE's guidelines.
2. Structure of Proposed part 197
The proposed EPA part 197 was structured in two subparts. Subpart A
of the rule would establish the public health and safety standards for
storage of spent nuclear fuel and high level waste at Yucca Mountain;
subpart B would establish the public health and safety standards for
disposal of spent nuclear fuel and high level waste at Yucca Mountain.
64 FR 47013-47016. The following is an overview of the main components
of EPA's proposed rule; in many areas of the rule EPA proposed
alternative language and requirements for public review and
consideration. For simplicity, not all of those alternative
possibilities are presented here.
For storage of spent nuclear fuel and high level waste, EPA
proposed a standard limiting the annual committed effective dose
equivalent (CEDE) to no more than 150 microsieverts (15 millirems
(mrem)) to any member of the public in the general environment. 64 FR
47013. This limit would apply to releases from the combination of
management and storage of spent nuclear fuel and high level waste that
is within the Yucca Mountain repository (below ground) and outside the
Yucca Mountain repository but within the Yucca Mountain site
(aboveground). EPA proposed this standard to be consistent with the
risk level set in its generic standards for management and storage of
spent nuclear fuel, high level waste, and transuranic waste, codified
at subpart A of 40 CFR 191 and with its interpretation of section 801
of EPACT requiring it to set site-specific standards for storage of
waste at Yucca Mountain. 64 FR 46983-46984. In EPA's view, storage of
waste, whether inside the Yucca Mountain repository or outside the
Yucca Mountain repository but within the Yucca Mountain site, presents
the same technical situation and is analogous to the storage of
radioactive waste at other facilities covered by 40 CFR part 191.
Accordingly, EPA proposed the storage standard for Yucca Mountain be
essentially the same as the standard applicable to other facilities
subject to subpart A of 40 CFR part 191.
For disposal of spent nuclear fuel and high level waste, EPA
proposed three standards--an individual protection standard, a human
intrusion standard, and a ground water standard--compliance with which
DOE would need to demonstrate to the satisfaction of the NRC to ensure
protection of public health and safety. 64 FR 47013-47016. Under the
individual protection standard, DOE would be required to demonstrate
that there is a reasonable expectation that for 10,000 years following
disposal a hypothetical reasonably maximally exposed individual (RMEI)
receives no more than an annual committed effective dose equivalent
(CEDE) of 150 microsieverts (15 millirems (mrem)) from releases from
the undisturbed Yucca Mountain disposal system. All potential pathways
must be included in this analysis. In proposing this individual
protection standard, EPA concluded that radiation containment
requirements, such as those embodied in 40 CFR part 191, were not
necessary in order to protect members of the general public from
releases from a repository at Yucca Mountain.
For the proposed human intrusion standard, EPA proposed two
alternative rules, one of which would impose an annual CEDE limit of
150 microsieverts (15 mrem) to a RMEI based on an assumed human
intrusion event, while the alternative rule would impose the dose limit
if complete waste package penetration can be shown to occur before
10,000 years after disposal. EPA also proposed a rule outlining the
elements of the human intrusion scenario to be used in the analysis. 64
FR 47015.
Under the proposed ground water protection standard, EPA would
require DOE to provide in its license application a reasonable
expectation that for 10,000 years of undisturbed performance after
disposal, releases of radionuclides from radioactive material in the
Yucca Mountain disposal system will not cause the level of
radioactivity in the representative volume of ground water at the point
of compliance to exceed certain limits (e.g., combined beta and photon
emitting radionuclides cannot exceed a limit of 40 microsieverts (4
millirems) per year to the whole body or any organ). EPA presented for
public review and comment several alternatives for the selection of the
representative volume of water and for the location of the point of
compliance. 64 FR 47015-47016.
EPA's proposed approach to setting public health and safety
standards for a repository at Yucca Mountain followed the NAS
recommendations and findings. Although EPA proposed some requirements
in its rulemaking that differ from certain NAS findings and
recommendations (for example, EPA proposed use of a dose standard
instead of a risk standard, and use of the RMEI concept instead of
critical group), EPA's proposed rule is consistent with the
[[Page 57309]]
primary NAS findings and recommendations that a public health standard
based on risk or dose to an individual member of the public can be
protective of general public health and safety, and that the Yucca
Mountain-related physical and geologic processes are sufficiently
quantifiable and the related uncertainties sufficiently boundable that
the performance can be assessed over certain time frames. 64 FR 46980-
46983.
In the case of the individual protection standard, EPA would
expressly require DOE to use performance assessment to calculate the
dose limits established in its proposed radiation protection standards
for disposal. 64 FR 47014. Although EPA generally would not prescribe
requirements on how the performance assessments would be conducted, it
would impose certain limitations. For example, proposed section 197.40
would not require consideration by DOE in its performance assessments
of events that are estimated to have less than one chance in 10,000 of
occurring within 10,000 years of disposal. 64 FR 47016. In addition,
EPA acknowledged certain inherent limitations in DOE's ability to
demonstrate compliance with the public health and safety standard
through use of performance assessment, but nevertheless mandated the
use of that method of assessment. EPA's proposed rule recognized,
through the concept of reasonable expectation, that, among other
things, there are inherent uncertainties in making long-term
projections of the performance of the Yucca Mountain disposal system,
that performance assessments and analyses should be focused upon the
full range of defensible and reasonable parameter distributions, and
that assessments should not exclude important parameters simply because
they are difficult to quantify precisely to a high degree of
confidence. 64 FR 46997-46998; 64 FR 47014.
L. DOE's 1999 Notice of Proposed Rulemaking
On November 30, 1999, DOE published a revised notice of proposed
rulemaking (64 FR 67054) in order to revise its December 16, 1996,
proposal (61 FR 66158) to amend 10 CFR part 960, the ``General
Guidelines for the Recommendation of Sites for Nuclear Waste
Repositories'' and to issue proposed Yucca Mountain Site Suitability
Guidelines under a new part 963.
In its December 16, 1996, proposal, DOE had published proposed
regulatory amendments to the Guidelines to reflect the prevailing
scientific view on how to evaluate the suitability of the Yucca
Mountain site for the development of a nuclear waste repository.
Because the preliminary site screening stage was complete and Congress
had required DOE to focus on Yucca Mountain, Nevada, DOE's proposed
regulatory amendments dealt with provisions of the Guidelines
applicable to the site recommendation stage. In its November 30, 1999,
revised proposal, DOE revised the terms of its proposal for three
reasons.
First, during the comment period on the December 16, 1996,
proposal, DOE received comments from members of the public, State and
local officials of Nevada, the EPA, and the NWTRB, that in substance
criticized the omission from the proposed regulatory amendments of
essential details of the criteria and methodology for evaluating the
suitability of the Yucca Mountain site for the location of a nuclear
waste repository. Some of the comments made pointed recommendations for
Guidelines at a more definitive level of specificity than the proposed
regulatory text provided. Also, there were comments critical of the
legal basis for DOE's proposal and its consistency with what those
commenters viewed as DOE's past position on the meaning of sections
112(a) and 113(b) of the Act. As explained in detail later in this
notice, DOE concluded that there was enough merit in these comments to
warrant revision of the proposed regulatory amendments and expansion of
the explanation of the factual and legal bases for them.
Second, in December, 1998, DOE issued, pursuant to Congressional
direction, the Viability Assessment. This document, which is available
through the Internet on the web site (www.ymp.gov) or in hard copy upon
request (see FOR FURTHER INFORMATION CONTACT) set forth the bases for
the site suitability criteria DOE is proposing to use and the
methodology for applying the criteria to a design for a proposed
repository at the Yucca Mountain site. DOE can now assist commenters in
responding to DOE's proposal with appropriate descriptions of, and
references to, key portions of the Viability Assessment in the
Supplementary Information.
Third, after the close of the comment period, as noted above, the
NRC, consistent with Congressional direction to the EPA to develop a
site-specific radiation protection standard for the Yucca Mountain
site, proposed site-specific licensing requirements for that site in a
new 10 CFR part 63 and to eliminate the site from coverage under 10 CFR
part 60. Thereafter, EPA issued the Congressionally-mandated proposal
for site-specific public health and safety standards for a repository
at Yucca Mountain, to be codified at 40 CFR part 197. Section 113(c) of
the NWPA provides that a determination of site suitability for
development as a repository is largely an estimate that an application
to the NRC for a construction authorization would be successful (42
U.S.C. 10133(c)). Thus, the details of the EPA and NRC proposals, which
were not available when DOE formulated its December 16, 1996, proposal,
affected the likely continuing usefulness of existing 10 CFR part 960,
the text of DOE's proposed regulatory amendments, and the bases for
those proposed amendments in performing the analysis required by
section 113. For reasons explained in detail in its 1999 revised
proposal, DOE presented the view that the proposed part 63, if
finalized without significant change, would make it illogical to apply
the existing provisions of 10 CFR part 960, which are explicitly linked
to provisions of the NRC's part 60. Moreover, the details of the NRC's
proposal suggested the need for making conforming changes to the
December 16, 1996, proposal to set forth the requirements for carrying
out a total system performance assessment as the method for applying
the site suitability criteria to the data developed during site
characterization of the Yucca Mountain site.
Consistent with EPA's proposal for site-specific public health
standards and NRC's proposal to limit part 60 and to establish a new
part 63 for the Yucca Mountain site, DOE proposed regulations to: (1)
Limit 10 CFR part 960 to preliminary site screening for repositories
located elsewhere than Yucca Mountain; and (2) establish a new part 963
to set out the site suitability criteria and the methods for
considering the potential of the Yucca Mountain site for a nuclear
waste repository under those criteria. Although closely linked to the
NRC's proposed part 63 licensing criteria and requirements, as is
necessary and appropriate, DOE's proposed regulations in part 963 in no
way determined that the site necessarily will or will not meet all
requirements to obtain a license from the NRC, or to be recommended by
the Secretary for development as a geologic repository. Rather, DOE
issued the proposed rule to better define policies and criteria to
guide the determination of the suitability of the Yucca Mountain site
in terms of, and based on, the information and data developed through
the program of site characterization
[[Page 57310]]
activities DOE has conducted over the years at Yucca Mountain under
section 113(b) of the NWPA.
In issuing the revised notice, DOE sought to improve its policies
for determining site suitability by enhancing their transparency,
validity, and verifiability. In terms of enhancing transparency, DOE
aimed at regulations that are easier to read and understand. In terms
of enhancing validity, DOE aimed at an explanation of the legal and
scientific basis for the regulations that shows how DOE's policies
logically follow from scientifically supportable and legally sound
premises. In terms of enhancing verifiability, DOE aimed at showing
that the scientific conclusions underlying its policies are based on
documented empirical results of experiments, and computer analyses of
relevant data so as to allow verification of the conclusions DOE might
eventually draw from known facts in evaluating the suitability of Yucca
Mountain as a potential repository site.
DOE followed the consultation procedures set forth in section
112(a) of the NWPA for promulgation of the Guidelines in seeking review
and comment on this revised proposal.
M. Final EPA and NRC Regulations
On June 13, 2001, EPA issued 40 CFR part 197 (66 FR 32074-32135),
establishing public health and environmental radiation protection
standards for a geologic repository at the Yucca Mountain site. The
final standards are consistent with the proposed standards, and reflect
changes largely associated with the selection, from among proposed
alternatives, of certain implementing assumptions and conditions.
Consistent with the EPA proposed rule, final 40 CFR part 197 subpart A
prescribes a standard for storage limiting the annual committed
effective dose equivalent to no more than 15 millirems (mrem) to any
member of the public in the general environment from the management and
storage of spent nuclear fuel and high-level waste that is within the
Yucca Mountain repository (below ground) and outside the Yucca Mountain
repository but within the Yucca Mountain site (above ground).
Similarly, consistent with the EPA proposed rule, final 40 CFR part 197
subpart B prescribes three public health and environmental standards
for disposal--an individual protection standard, a groundwater
standard, and a human intrusion standard--governing the disposal of
spent nuclear fuel and high level waste at a Yucca Mountain repository.
The numerical radiation limits associated with each of the three
standards are the same as in EPA's proposal. For the individual
protection standard, the dose limit is 15 mrem annual committed
effective dose to the reasonably maximally exposed individual. 40 CFR
part 197.20. For the human intrusion standard, the dose limit is 15
mrem in the case where a stylized human intrusion event is projected to
occur before 10,000 years without recognition by the driller. 40 CFR
part 197.25. For the ground water protection standard, the limit for
radionuclide concentrations in the representative volume of water is 4
mrem per year to the whole body or any organ, and radionuclide
concentration limits of 5 and 15 picocuries per liter, respectively,
for radium-226 and radium-228, and gross alpha activity. 40 CFR part
197.30. Consistent with the EPA proposed rule, the final rule requires
that DOE demonstrate compliance with the individual protection standard
by means of performance assessment. 40 CFR part 197.20.
In finalizing the rule, EPA selected and refined the requirements
for certain implementing assumptions and conditions for which EPA
sought public comment on the draft rule. For example, the location of
the reasonably maximally exposed individual was selected to be the
point above the highest concentration of radionuclides in the plume of
contamination (40 CFR part 197.21), but not further from the repository
than the southernmost boundary of the Nevada Test Site, that is, line
of latitude 36 deg. 40' 13.6661" North. 66 FR 32093. With respect to
the ground water standard, EPA defined the size of the representative
volume of water to be used in the compliance calculation to be 3,000
acre-feet based on a cautious but reasonable estimate of the size of
the ground water resources in the area of compliance and the current
and projected uses of that resource. 66 FR 32113. In determining
compliance with the human intrusion standard, EPA selected a standard
that requires DOE to determine the earliest time after disposal that a
waste package would degrade to such an extent that a driller would not
recognize the waste package. 40 CFR part 197.25. If this could occur at
or before 10,000 years after disposal, then DOE must demonstrate the
dose to the RMEI does not exceed 15 millirem; otherwise, the results of
the analysis must be included in the Yucca Mountain environmental
impact statement as an indicator of long-term performance. 40 CFR part
197.25.
Following promulgation of 40 CFR part 197, the NRC promulgated 10
CFR part 63 on November 2, 2001. In finalizing part 63, the NRC made
changes to its technical requirements and criteria necessary to be
consistent with the final environmental standards for Yucca Mountain
promulgated by EPA. The NRC identified three categories of changes to
incorporate the EPA standards into its rule: (1) the addition of two
subparts--Subpart K for storage and Subpart L for disposal--
corresponding to Subparts A and B of part 197, respectively; (2) the
adoption of provisions (e.g., EPA definitions) precisely as they appear
in part 197 and nonsubstantive changes to conform to the regulatory
style of the NRC; and (3) the adoption of additional specifications and
requirements where necessary to carry out the NRC's responsibilities as
the implementing agency for the standards. 66 FR 55733.
Accordingly, in final form, 10 CFR part 63 incorporates the public
health and environmental standards for the preclosure (management and
storage) and postclosure (disposal) periods as defined in 40 CFR part
197, along with many of the assumptions and requirements to be met in
demonstrating compliance with those standards. With respect to
demonstrating compliance with preclosure management and storage
requirements, the NRC adopted the standard set forth in 40 CFR 197.4,
and made clarifying changes to the titles and descriptions of the
requirements for the analysis of preclosure operations and safety. With
respect to demonstrating compliance with postclosure requirements, NRC
adopted the standards in 40 CFR part 197, Subpart B, added some
implementing provisions, and clarified language in the rule. For
example, NRC adopted the reasonably maximally exposed individual,
instead of the average member of the critical group, as the
hypothetical person for whom radiation dose limits are to be calculated
to demonstrate compliance with the individual protection and human
intrusion standards. 10 CFR 63.311, 63.312. In addition, the NRC added
standards for ground water protection, and the associated requirements
for calculating radionuclide releases to the ground water, which were
not addressed in proposed part 63. 10 CFR 63.331. NRC also revised its
human intrusion standard to conform to 40 CFR part 197 requirements
that require DOE to estimate when a waste package will be fully
breached within 10,000 years after disposal to such an extent that the
driller would not recognize the package, and, based on this analysis,
determine whether the 15 millirem dose limits
[[Page 57311]]
would apply or whether the analysis need only be incorporated into the
Yucca Mountain environmental impact statement. 10 CFR 63.321. Other
prescribed assumptions, such as the characteristics of the RMEI and the
reference biosphere (10 CFR 63.312 and 63.305, respectively), and the
definition of representative volume of water for calculating the
radionuclide releases to the ground water (10 CFR 63.332), were adopted
by the NRC as promulgated by the EPA.
As explained in section VI of this SUPPLEMENTARY INFORMATION, DOE
has modified part 963 as necessary to conform to the changes made in
final part 63. These changes to part 963 do not require a reopening of
the public comment period on part 963, as they consist of minor
clarifications and non-discretionary, conforming changes to make part
963 consistent with final part 63, as it implements final part 197.
N. NRC Concurrence
DOE provided a draft final version of the part 963 rule to the NRC
for its concurrence. NRC's concurrence on this rule was obtained by DOE
on October 19, 2001; a notice of this decision was published in the
Federal Register on October 26, 2001. 66 FR 54303. NRC concurrence was
contingent on a final part 963 rule that was not substantively
different from the draft final version reviewed by the NRC for
concurrence. As explained above and in section VI of this SUPPLEMENTARY
INFORMATION, DOE has made only minor clarifications and non-
discretionary, conforming changes to part 963 to make it consistent
with final NRC and EPA regulations.
III. Basis for Final Rule
A. Legal Authority and Necessity to Amend the Guidelines and Criteria
1. Overview
Section 112(a) of the NWPA explicitly establishes DOE authority to
``issue general guidelines for the recommendation of sites for
repositories'' and to ``use [the] guidelines established under this
subsection in considering candidate sites for recommendation under
subsection (b).'' Subsection (b) of section 112 provides for a process,
to be conducted following promulgation of the Guidelines that would
result in: (1) The nomination of 5 potential sites for
characterization; and (2) the selection of 3 of those 5 sites for
recommendation to the President as suitable for site characterization
activities. Section 112(a) also includes explicit authority to revise
the Guidelines, from time to time, consistent with the provisions of
112(a).
Shortly after the enactment of the NWPA, DOE promulgated Guidelines
(codified at 10 CFR part 960) to implement section 112. The approach
taken at that time was to structure the Guidelines to provide a
framework not only for the section 112 decisions (for which it was
statutorily required) but also for subsequent steps in the site
selection process. Consistent with this approach, the Guidelines as
originally promulgated also addressed actions to be taken under
sections 113 and 114. Section 113(b) provided that DOE should include
in its site characterization plan ``criteria to be used to determine
the suitability of [a] site for the location of a repository, developed
pursuant to section 112(a).'' 49 FR 47730. DOE did not need to decide
whether this meant that it had to use the same Guidelines it had
previously developed under section 112(a) or whether it was free to use
other criteria provided it developed them pursuant to the procedures
set out in 112(a). It rejected the alternative suggested, that it use
the NRC licensing standards, because (1) the Guidelines had been
written to be consistent with the licensing standards, and (2) the
Guidelines were more relevant than the licensing standards to the
particular decision at issue, that is, they were ``intended to be used
in deciding which among the characterized sites is to be recommended to
the President, the Congress, and finally to the NRC for appropriate
approvals.'' 49 FR 47730. (emphasis added) That approach was
understandable in 1984 when DOE anticipated the need to evaluate by
comparison multiple characterized sites, a comparison similar to the
choosing of sites for characterization for which the Guidelines were
required by section 112(a) of the NWPA. After the 1987 amendments to
the NWPA designated Yucca Mountain as the only site to be
characterized, DOE indicated that it nevertheless need not revise the
Guidelines because it could apply some, but not all, of the Guideline
provisions in the Site Characterization Plan prepared under section
113(b) of the NWPA as criteria to determine site suitability. DOE/RW-
0199 (1988). DOE reiterated that conclusion in 1995 when it
reconsidered the Guidelines in the context of evaluating the
suitability of the Yucca Mountain site under the Site Characterization
Plan. DOE decided then that ``[b]ecause DOE need apply only the
relevant provisions'' of the Guidelines, amending or supplanting them
with ``Guidelines specifically tailored'' to evaluating the suitability
of the Yucca Mountain site was ``not required at this time.'' 60 FR
47737, 47740 (1995).
As discussed in greater detail below, DOE has now determined that a
new approach is called for in light of the cumulative effect of the
intervening legislative, regulatory, and technical developments that
have occurred since 1984. As a result of these developments, neither
explanation that DOE gave in 1984 for using the part 960 Guidelines--
that they were consistent with the NRC's licensing criteria and that
they were an appropriate tool because they were developed to assist in
making comparative judgements about sites--remains valid in today's
circumstances. Congress and the regulatory agencies acting pursuant to
Congressional directive have changed the regulatory landscape in such a
way that the part 960 Guidelines no longer fit comfortably within that
framework. And the 1987 amendments to the NWPA have eliminated any
obligation on DOE's part to make comparative judgements about sites in
the course of making the suitability determination. Accordingly, DOE
has now developed criteria, using section 112(a) procedures in the
development of these criteria, but not adopting the particular section
112(a) Guidelines as these criteria, to form the basis for a
determination of the suitability of the Yucca Mountain site for the
location of a repository. The rationale for this approach stems from
the combination of the 1987 amendments' directive to DOE to focus on
Yucca Mountain alone, the basic analysis for assessing repository
performance recommended by the National Academy of Sciences, which
differs from that embedded in the 1984 Guidelines, and the adoption by
the NRC of new regulations for licensing repositories which, under the
NWPA's structure, must define the areas and methodology of DOE's
inquiries into Yucca Mountain's suitability.
Accordingly, DOE today issues final revisions to the existing
Guidelines at 10 CFR part 960 to limit their application to only the
initial site selection process set forth in section 112. DOE may make
additional revisions to these Guidelines if, in the future,
circumstances were to change and DOE were to reinitiate a preliminary
site screening process under section 112. Further, DOE today
promulgates a new rule, consistent with section 113(b)(1)(A)(iv), to
establish criteria to be used in determining the suitability of Yucca
Mountain for the location of a geologic repository. The criteria
identified in this new rule allow for consideration of the impact of
the geologic factors and considerations
[[Page 57312]]
referenced in section 112(a), as they relate to DOE's current
scientific understanding and methodology for assessing the suitability
of the Yucca Mountain site as a location for a repository.
2. Section 112
DOE's approach in today's final rule is consistent with the text of
section 112(a) and the basic structure of the NWPA, as originally
enacted and as amended. As originally enacted, the NWPA set up a
sequential process for selecting, comparing, and evaluating potential
sites for the development of a geologic repository for high-level
waste. The 1987 amendments eliminated any continued comparison of
sites; only Yucca Mountain is authorized for site characterization
activities leading to possible recommendation as a repository site.
Beyond the first step in the process, recommendation of multiple sites
for site characterization (section 112), there is no explicit direction
in the Act (in its original enactment or amendment) whether or how to
utilize the Section 112(a) Guidelines in the succeeding site selection
processes (sections 113 and 114). Instead, section 112(a) specifies the
intended use of the Guidelines: ``[t]he Secretary shall use guidelines
established under this subsection in considering sites to be
recommended for site characterization under section 112(b).'' Likewise,
the environmental assessment of the various sites nominated for
characterization pursuant to section 112 is to include ``evaluation''
of each nominated site under each Guideline not requiring
characterization for its application and all the Guidelines pertinent
to whether or not a site is ``suitable for site characterization'' (42
U.S.C. 10132(b)(1)(D)(I)&(ii)). Nowhere in its text does section 112
require any additional use of the Guidelines.
In sum, the text of section 112 and its relation to other
provisions in the NWPA indicate that the Guidelines are to govern the
process of selecting and comparing among potential sites to determine
which sites are appropriate to proceed to the next, more detailed
evaluation stage, site characterization. In contrast, nothing in the
text of section 112 specifies that the Guidelines it requires are also
to govern the process for determining site suitability and site
recommendation under sections 113 and 114.
3. Section 113
Section 113 of the NWPA requires DOE to prepare a site
characterization plan for a candidate site selected under section 112
for site characterization activities. A required element of a site
characterization plan is ``criteria to be used to determine the
suitability of such candidate site for the location of a repository,
developed pursuant to section 112(a)'' (42 U.S.C. 10133(b)(1)(A)(iv)
(emphasis added)). The NWPA does not define the term ``criteria,''
thereby suggesting the Secretary has broad discretion to determine the
scope and content of the criteria in question.
Section 113(b) requires that the ``criteria'' to be included in the
Site Characterization Plan be ``developed pursuant to section 112(a)''
of the NWPA. Because section 112(a) of the NWPA is devoted to the
``Guidelines'' for selecting candidate sites while section 113(b) is
devoted to the ``criteria'' under which selected candidate sites
subsequently are to be characterized, it is necessary to consider what
section 113's requirement that the criteria be ``developed pursuant to
section 112(a)'' means in terms of any required correspondence or other
relationship between the Guidelines and the 113(b) criteria.
It is unlikely that the Congress intended to require the
``criteria'' to be the Guidelines themselves. It would have been simple
enough for Congress to have legislated that policy in section 113(b) by
a straightforward requirement that the Site Characterization Plan
specify that the ``Guidelines developed pursuant to section 112(a)''
would be used ``to determine the suitability of each candidate site''
(Compare 42 U.S.C. 10133(b)(1)(A)(iv)). Had Congress intended this
policy result it is unlikely that it would have chosen such an
elliptical and opaque way of expressing it as the actual statutory text
that does not use the term ``Guidelines'' at all. And a construction of
section 113(b) requiring the suitability ``criteria'' to be the same as
the section 112 Guidelines would risk tension with section 113(c)'s
restriction that limits DOE to conducting ``only'' characterization
activities ``necessary to provide the data required'' to prepare an NRC
license application. The NRC, of course, is not required to base its
licensing standards on the Guidelines adopted by DOE under section
112(a) of the NWPA (although it was required to concur in them), nor
does section 112 afford the NRC the ability to compel DOE to
reformulate the Guidelines should the NRC determine to amend or
supplant its licensing standards.
On the other hand, section 112(a) contains specific procedural
mandates required to be employed by DOE in issuing or revising the
Guidelines. Before DOE may promulgate the Guidelines, DOE must consult
with several specified federal agencies and with ``interested
Governors'' (42 U.S.C. 10132(a)). In addition, the NRC must
``concur[]'' in the issuance of the Guidelines. Id. These distinctive
procedural requirements obviously are tailored to the particular
circumstances of site decision-making under the NWPA and specify
procedural requirements that would not otherwise obtain under the
rulemaking provisions of the Administrative Procedure Act or the
rulemaking provisions of the Department of Energy Organization Act that
were in force when the NWPA was adopted. It would therefore make sense
that Congress would want these procedures used for developing the
section 113 ``criteria'' as well as the section 112 ``guidelines.''
The requirement of section 113(b) that the SCP's ``criteria'' for
characterizing sites be ``developed pursuant to section 112(a)''
therefore is best understood as mandating observance of the special
procedural requirements of section 112(a) in formulating or altering
the section 113(b) ``criteria.'' This understanding of the statutory
text seems the most faithful to its explicit terms and the larger
statutory context in which it occurs. Moreover, it seems the only
understanding of section 113(b) that is consistent with the 1987
changes to the NWPA (which mandated exclusive characterization work for
the Yucca Mountain site without amending section 113(b) despite
amending the statute elsewhere to remove the element of comparing
sites, to which the Guidelines of section 112(a) were devoted). This
understanding of the requirements of section 113(b) also comports with
DOE's prior understanding, as was described in the 1995 notice, that
not all the original Guideline elements need be applied in site
characterization under section 113 of the NWPA. To the extent the
statutory provisions are ambiguous, this interpretation seems best
designed to result in the establishment of ``criteria'' that comport
with what DOE believes to be the better policy approach to determining
site suitability.
B. Events Necessitating Amendment of the Guidelines and Criteria
1. Congressional Redirection of the Program
Since the NWPA was enacted in 1982 and the Guidelines promulgated
in 1984, Congress has made major changes to the framework for
developing a geologic repository. These changes are described below
and, in part, form the basis for the revisions to 10 CFR part
[[Page 57313]]
960 and the promulgation of a new 10 CFR part 963 as presented in this
notice of final rulemaking.
1987 Amendments to the NWPA. Congress amended the NWPA in 1987 to
select Yucca Mountain as the only site to be characterized. Congress,
accordingly, directed DOE to terminate site-specific activities at the
two other sites that had been recommended for site characterization in
1986 (42 U.S.C. 10172). Further, Congress restricted DOE's
characterization activities at Yucca Mountain to only those the
Secretary considers necessary to provide the data required for
evaluation of the suitability of the site for NRC construction
authorization (i.e., license application), and for compliance with the
National Environmental Policy Act of 1969, as modified to excuse DOE
from conducting analyses of alternatives that NEPA would otherwise
require. A provision was added to the NWPA to provide for termination
of site characterization activities at Yucca Mountain if at any time
the Secretary determines that Yucca Mountain is unsuitable for
development as a repository.
Although the 1987 amendments to the Act were decisive in focusing
the repository program and DOE's efforts on one specific site, for many
years DOE maintained that these changes were not so significant as to
warrant amendment of the Guidelines. Instead, DOE believed the
Guidelines, for the most part, could be applied to Yucca Mountain for
purposes of determining the suitability of the site (because Yucca
Mountain already had been found suitable for characterization under
other provisions of the Guidelines) in support of a possible site
recommendation by the Secretary. DOE believed that the only changes to
the Guidelines necessitated by the 1987 amendments were to eliminate
consideration of those parts of the Guidelines related to comparative
analysis. Similarly, the NRC had not made significant modifications to
its technical requirements and criteria in 10 CFR part 60 as a result
of the 1987 amendments to the Act.
1992 Energy Policy Act. In the 1992 Energy Policy Act, Congress
reinforced its directive that Yucca Mountain was to be the exclusive
focus of the nation's repository program, by explicitly extending that
directive not only to DOE activities, but also to activities of EPA and
NRC, the other federal agencies with authority and responsibility over
the repository program. Section 801 of the EPACT directed the EPA to
promulgate, by rule, new public health and safety standards for the
protection of the public from releases from radioactive materials
stored or disposed of in a repository at the Yucca Mountain site.
Unlike EPA's previous standard, which applied generally to geologic
repositories and included limits on radioactive releases to the
environment, the new standards were required to prescribe the maximum
annual effective dose equivalent to individual members of the public
from releases to the accessible environment from radioactive materials
stored or disposed of at Yucca Mountain. To aid EPA in this process,
Congress directed a National Academy of Sciences (NAS) study to provide
findings and recommendations on reasonable standards for protection of
the public health and safety. EPA was required to base its new
standards on the findings and recommendations of the NAS. For Yucca
Mountain, these standards would replace the generally applicable
standards for the protection of the general environment that the EPA
had promulgated at 40 CFR part 191 pursuant to section 121 of the NWPA.
The EPACT also directed the NRC to modify its technical
requirements and criteria, as necessary, to be consistent with the
EPA's new standards. In addition, NRC was directed to ensure that,
consistent with the NAS findings and recommendations, its requirements
and criteria for postclosure oversight of a Yucca Mountain repository
would be sufficient to prevent any activities at the site from posing
an unreasonable risk of breaching the engineered and natural barriers
of the site, and to prevent any increase in exposure of individual
members of the public beyond allowable limits.
These changes were significant because they set the stage for
future regulatory changes governing the standards a Yucca Mountain
repository must meet to ensure public health and safety, and to obtain
a license for construction. The ability to meet regulatory standards
has always been a dominant factor in the site selection process. This
requirement is reflected in the structure of the Guidelines, is
reinforced by the 1987 amendments to the Act, and is a prime focus of
DOE's site characterization program. Thus, the Congressional mandate in
the EPACT directing new and revised regulations governing geologic
disposal at Yucca Mountain necessarily affected DOE's formulation of
the criteria that will be used to determine the suitability of Yucca
Mountain as a site for development of a repository. Until recently,
however, the full extent and nature of those impacts had not been
defined. The NRC's proposal to amend 10 CFR part 60, its technical
requirements and criteria for licensing a repository to exclude Yucca
Mountain from their scope, to add a new part 63 specific to Yucca
Mountain, provided DOE with an outline of anticipated regulatory
changes, and signaled for DOE how and why it must conform its
Guidelines and criteria for determining the suitability of the Yucca
Mountain site for the location of a repository.
Fiscal Years 1996 and 1997 Appropriations Acts and the Viability
Assessment. Finally, in response to budgetary concerns, the Conference
Report on the Energy and Water Development Appropriations Act, 1996
(Pub. L. No. 104-46) (H.R. Rep. No. 293, 104th Cong., 1st Sess. 68
(1995)) directed the DOE to focus on only those activities necessary to
assess the performance of a repository at the Yucca Mountain site and
to collect the scientific information needed to determine the site's
suitability. DOE responded by revising its Program Plan for 1996 in
which it indicated that, among other changes, DOE would complete a
viability assessment of the Yucca Mountain site in 1998, and would
develop a proposal to amend the Guidelines and develop new regulations
specific to the Yucca Mountain site. Congress indicated its approval of
the changes by directing that appropriated funds be used in accordance
with the revised program plan. Congress reinforced this direction in
the Fiscal Year 1997 Energy and Water Appropriations Act, where it
mandated that DOE provide to the Congress and the President a viability
assessment of the Yucca Mountain site in 1998.
These changes in budget for DOE's civilian radioactive waste
management program indicate congressional intent for DOE to focus site
characterization activities on assessing the viability and suitability
of Yucca Mountain, and to complete those activities in the near term.
In light of this congressional direction, it is reasonable for DOE to
amend the Guidelines in a manner that acknowledges Yucca Mountain as
the only site at which site characterization has occurred and for which
DOE would need to conduct a suitability evaluation under section
113(b).
2. Consistency Between DOE and NRC Regulations
Procedural Consistency. The DOE's site characterization suitability
criteria must be consistent with the NRC's licensing criteria if the
DOE is to present a potentially successful license application to the
NRC. Such consistency originally was attained in the Guidelines through
the NRC's concurrence process, as required by section 112(a) of the
NWPA. DOE stated
[[Page 57314]]
in proposed part 963 that it would preserve this consistency in the
final suitability criteria by ensuring that they reflect the changes to
the licensing criteria in NRC's new rule 10 CFR part 63, and by
soliciting NRC concurrence on DOE's final amendments to the guidelines
and the promulgation of a new regulation at 10 CFR part 963.
Substantive Consistency. NRC's proposed new rule establishing the
technical requirements and criteria for repository licensing at Yucca
Mountain, proposed 10 CFR part 63, was different from its prior general
rule on repository licensing, 10 CFR part 60. DOE accordingly had
little choice but to propose site suitability criteria that would be
consistent with the NRC's proposed licensing requirements. The
suitability of a site for the location of a repository is a function of
the DOE's ability to demonstrate the site can meet applicable
regulatory requirements. Section 113 makes clear that the evaluation of
``suitability'' is an evaluation of the ``suitability of [the Yucca
Mountain] site for an application to be submitted to the [NRC] for a
construction authorization for a repository at such site'' and that the
function of site characterization is to generate the data to evaluate
whether a site can meet that standard. DOE has conducted the site
characterization program at Yucca Mountain with that statutory
objective of evaluating its ability to obtain construction
authorization from the NRC for a repository at that site (i.e., to meet
NRC licensing requirements and EPA health and safety standards, as
implemented by NRC through the license). DOE could not scientifically
and technically arrive at a suitability determination, without
conforming its criteria for suitability to the proposed NRC technical
requirements and criteria for a repository license. Such conforming
criteria are finalized in this notice.
The NRC proposed rule part 63 was a departure from the philosophy
and technical requirements of 10 CFR part 60. It was based on the 1995
NAS report recommending a risk-limit standard for a repository at Yucca
Mountain. The NRC timed publication of its proposal to ensure NRC would
have sufficient time, once EPA issued its new standard, to put the new
licensing standards in effect. The proposed rule embodied a new
approach of risk-informed, performance-based regulation, and was
specific to Yucca Mountain. The old rule relied on subsystem
performance objectives and a release limit standard. Under the proposed
rule, the performance of a Yucca Mountain repository would be evaluated
against a health-based standard in consideration of risk to a
hypothetical critical group and this standard would be the only
quantitative standard for the postclosure performance of the
repository. The new rule would require DOE to demonstrate compliance
with postclosure technical criteria through performance assessments,
and preclosure criteria through an integrated safety analysis. The new
approach embodied in the proposed rule would eliminate current part 60
design and siting criteria, as well as quantitative subsystem
requirements, but would add specific requirements for the content of
performance assessments to ensure their sufficiency and adequacy. In
other words, a proposed Yucca Mountain repository would be evaluated as
an entire system, not by assessing its individual parts in isolation,
in order to determine whether or not it meets applicable standards to
protect public health and safety.
It was clear that if this proposal was finalized in substantially
the same form as proposed the current structure of DOE's part 960
guidelines, which is premised on a demonstration of system and
subsystem technical requirements, would no longer be consistent with,
and in some cases might conflict with, the NRC technical requirements
to support a license application. For example, several of DOE's part
960 guidelines require compliance with the siting and design
requirements set forth in 10 CFR 60.113, 60.122 and 60.133. Those
requirements did not exist in proposed part 63 and would not be
applicable to Yucca Mountain under proposed amendments to part 60.
Those requirements are subsystem performance requirements that are
inconsistent with the NRC's new approach of evaluating the technical
merits of a potential site based on the performance of the repository
system as an integrated whole, and not on the performance of each part
independent of the other parts.
A good example of this is the geohydrology guideline at part 960.4-
2-1. Under this guideline, DOE set qualifying and disqualifying
conditions for the geohydrology of a site. The qualifying condition for
geohydrology requires that a site be capable of compliance with
radionuclide release limits set by EPA in 40 CFR part 191, and by NRC
in 10 CFR 60.112, as well as compliance with DOE subsystem performance
requirements that mirror NRC requirements in 60.113. The Yucca Mountain
site has been exempted by the EPACT from compliance with the
containment limits set by EPA under 40 CFR part 191, and the NRC's
proposed amendments to 10 CFR part 60 nullified the applicability of
60.113 to Yucca Mountain and create a new part 63 for which there is no
analogous release limit or subsystem performance objective for
geohydrology. Accordingly, it was clear that it would be illogical for
DOE to reach a finding relative to this qualifying condition, as
required by Appendix III, based on regulatory requirements that no
longer would be applicable to the Yucca Mountain site and therefore
could not support a determination regarding site suitability for the
Yucca Mountain site.
The DOE Guideline 960.4-2-1 also contains a disqualifying
condition. Under this condition, DOE would disqualify a site if the
pre-waste emplacement ground water travel time from the disturbed zone
to the accessible environment is expected to be less than 1,000 years
along any pathway of likely and significant radionuclide travel. Under
the analogous NRC provision, 60.113, there is a performance objective
directing that the pre-waste emplacement ground water travel time along
the fastest path of likely radionuclide travel from the disturbed zone
to the accessible environment must be at least 1,000 years or such
other travel time as approved by the NRC. Under NRC's proposed
revisions to its regulations, this subsystem performance requirement
would no longer apply to a repository at Yucca Mountain under part 60,
and it would not exist, nor would there be any requirement similar to
it, under new part 63. Accordingly, it would be illogical for DOE to
reach a finding relative to this disqualifying condition, as required
by Appendix III, based on regulatory requirements that no longer would
be applicable to the Yucca Mountain site and therefore could not
support a determination regarding the site suitability of the Yucca
Mountain site.
Below is a table further illustrating the inconsistencies between
the current Guidelines and the proposed part 63. Table 1 provides a
cross walk between the technical guidelines to be applied as the
criteria under section 113(b), their analog in existing part 60, and
their analog, if any, in proposed part 63.
[[Page 57315]]
Table 1
----------------------------------------------------------------------------------------------------------------
New 10 CFR part
Section Guideline Condition 10 CFR part 60 63
----------------------------------------------------------------------------------------------------------------
4-1(a)........................ System................ Qualifying........ 60.112........... 63.113
4-2-1(a)...................... Geohydrology.......... Qualifying........ 60.112/113....... 63.113/None
4-2-1(d)...................... ......do.............. Disqualifying..... 60.113(a)(2)..... None
4-2-2(a)...................... Geochemistry.......... Qualifying........ 60.112/113....... 63.113/None
4-2-3(a)...................... Rock Characteristics.. Qualifying........ 60.112/113....... 63.113/None
4-2-4(a)...................... Climatic Changes...... Qualifying........ 60.112........... None
4-2-5(a)...................... Erosion............... Qualifying........ 60.112........... None
4-2-5(d)...................... ......do.............. Disqualifying..... 60.122(b)(5)..... None
4-2-6(a)...................... Dissolution........... Qualifying........ 60.112........... None
4-2-6(d)...................... ......do.............. Disqualifying..... 60.112........... None
4-2-7(a)...................... Tectonics............. Qualifying........ 60.112........... None
4-2-7(d)...................... ......do.............. Disqualifying..... 60.112........... None
4-2-8(a)...................... Natural Resources..... Qualifying........ 60.122(c)(1)..... None
4-2-8(d)(1)................... ......do.............. Disqualifying..... 60.122(c)(1)..... None
4-2-8(d)(2)................... ......do.............. Disqualifying..... 60.122(c)(1)..... None
4-2-9 (a)..................... Site Ownership and Qualifying........ 60.121........... 63.121
Control.
5-1(a)(1)..................... System................ Qualifying........ 60.111........... 63.111
5-1(a)(3)..................... System................ Qualifying........ None............. None
5-2-1(a)...................... Population Density and Qualifying........ 60.111........... 63.111
Distribution.
5-2-1(a)(1)................... ......do.............. Disqualifying..... 60.122(6)........ None
5-2-1(a)(2)................... ......do.............. Disqualifying..... 60.122(6)........ None
5-2-1(a)(3)................... ......do.............. Disqualifying..... None............. None
5-2-2(a)...................... Site Ownership and Qualifying........ 60.121........... 63.121
Control.
5-2-3(a)...................... Meteorology........... Qualifying........ 60.111........... 63.111
5-2-4(a)...................... Offsite Installations Qualifying........ None............. None
and Operations.
5-2-4(d)...................... ......do.............. Disqualifying..... None............. None
5-2-8(a)...................... Surface Qualifying........ 60.122(c)(1)..... None
Characteristics.
5-2-9(a)...................... Rock Characteristics.. Qualifying........ 60.133(a)(1)..... None
5-2-9(d)...................... ......do.............. Disqualifying..... None............. None
5-2-10(a)..................... Hydrology............. Qualifying........ 60.111........... None
5-2-10(d)..................... ......do.............. Disqualifying..... None............. None
5-2-11(a)..................... Tectonics............. Qualifying........ 60.122(b)(1)..... None
5-2-11(d)..................... ......do.............. Disqualifying..... None............. None
----------------------------------------------------------------------------------------------------------------
As demonstrated in the above table, in most cases there is no
analog between the DOE Guidelines and NRC's proposed part 63. In
addition, the Guidelines could not continue to reference and rely on
revised part 60, since NRC's proposed revisions to part 60 would make
them inapplicable to a repository at Yucca Mountain. Under the
circumstances, it would be irrational and difficult, if not impossible,
for DOE to apply the Guidelines in their current form.
Under these changed circumstances, DOE felt it had to act to amend
its outdated Guidelines and conform its site suitability criteria to
the NRC rule for licensing a Yucca Mountain repository.
3. Improvements in Analytical Methods
DOE's final changes will also serve to conform the rules for
assessing the suitability of a site with the current scientific and
technical methods developed and utilized by DOE in its site
characterization program. The final changes in the regulatory scheme
reflect the advances in the scientific and technological understanding
of the processes relevant to assessing the long-term performance of a
geologic repository. The regulatory revisions issued by EPA, NRC and
DOE, mark a change from generic regulations based on limited
information about geologic disposal developed early in the Nation's
quest for sites for geologic disposal, to regulations promulgated
specifically for the Yucca Mountain site that reflect over 20 years of
data collection and intensive site characterization activities at the
Yucca Mountain site. It would be irrational for DOE to ignore these
changes, and continue to rely on technical requirements that are not
aligned with, and are not supported by, the prevailing scientific
knowledge and understanding.
As recognized by the NRC in its proposed part 63, during the more
than 15 years since the NRC promulgated its initial technical criteria
at 10 CFR part 60 (and DOE promulgated matching technical requirements
in 10 CFR part 960), there has been considerable evolution in the
capability of technical methods for assessing the performance of a
geologic repository at Yucca Mountain. 64 FR 8640-8641. These advances
result from both improved computer capability and better analytical
methods. Indeed, these changes for the first time enable the vast
quantities of data that have been collected through site
characterization to all be used in models that more accurately model
site performance. NRC stated that these new methods were not envisioned
when the part 60 criteria were established, and that their
implementation allows for the use of more effective and efficient
methods of analysis for evaluating conditions at Yucca Mountain than
the NRC generic criteria in part 60. 64 FR 8641. Moreover, NRC believes
that implementation of these new analytical methods for evaluating
Yucca Mountain will avoid the imposition of unnecessary, ambiguous, or
potentially conflicting criteria that could result from the application
of some of the generic requirements of 10 CFR part 60. 64 FR 8641.
The evolution in performance assessment methodology formed the
[[Page 57316]]
basis for DOE's 1996 proposal to amend the Guidelines. In that
proposal, DOE explained that only by assessing how specific design
concepts will work within the natural system at Yucca Mountain and
comparing the results of these assessments to the applicable regulatory
standards, can DOE reach a meaningful conclusion regarding the site's
suitability for development as a repository. The 1996 proposed
amendments to the Guidelines would have required a comprehensive
evaluation focused on whether or not a geologic repository at Yucca
Mountain would adequately protect the public and the environment from
the hazards posed by high-level radioactive waste and spent nuclear
fuel (61 FR 66160). DOE explained that recent results in four major
areas have advanced the ability to evaluate the Yucca Mountain site,
and geologic disposal, to the point that a system approach is now
appropriate. These four areas are: (1) Analysis and integration of data
collected from surface-based testing and regional studies; (2)
examination of the potential repository horizon made possible by the
excavation of the Exploratory Studies Facility; (3) the site-specific
conceptual design of the engineered facilities; and (4) performance
assessment analyses (61 FR 66161).
Like the NRC, DOE recognized that this improved understanding
counseled in favor of reexamining General Guidelines that may be
unnecessary or ambiguous, or that may present conflicting requirements
for Yucca Mountain. Based on the DOE's accumulated knowledge, and
significantly enhanced understanding, DOE has determined that a system
performance approach provides the most meaningful method for evaluating
whether or not the Yucca Mountain site is suitable for development as a
repository. In today's final rule, DOE expands on its 1996 and 1999
proposals to modify the Guidelines and incorporates performance
assessment as the appropriate approach to assess the forecasted
performance of a repository. This final rule provides greater detail,
comprehension and transparency of information describing the
performance assessment methodology, and how it serves as a foundation
for site characterization suitability criteria.
IV. Response to Public Comments on the 1999 Proposal
DOE published the supplemental notice of proposed rulemaking on
November 30, 1999, in the Federal Register (64 FR 67054), and posted it
on the Internet that same day. The public comment period on the
supplemental notice extended from the date of publication until
February 28, 2000. Public hearings were held on the supplemental
notice: two sessions in Pahrump, Nevada and two sessions in Las Vegas,
Nevada.
DOE received numerous comments on the supplemental notice, both
oral and written, from members of the public, State and local
officials, Native Americans, regulatory and oversight organizations,
and representatives of various non-governmental organizations, and the
nuclear power industry. Opinions about the supplemental notice were
divided. Some comments were critical of DOE's conduct of this
rulemaking. In particular, several commenters expressed a desire for
greater dialogue on the rulemaking, additional time to review the
proposed rulemaking, and frustration regarding the overlapping public
comment periods on this rulemaking and DOE's draft Environmental Impact
Statement for a Geologic Repository for the Disposal of Spent Nuclear
Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County,
Nevada (hereafter ``Yucca Mountain EIS''). DOE acknowledges the
comments, questions, and concerns raised by members of the public
during this rulemaking, and has considered them in preparing this
notice of final rulemaking. However, DOE believes that the comment
period on this rulemaking, lasting 89 days, and the comprehensive
background and description of the proposed rulemaking contained in the
supplemental notice, provided the public with sufficient time and
information to review the supplemental notice and provide meaningful
comments. In addition, the public hearings on this rulemaking, although
they coincided with some other public hearings on the Yucca Mountain
EIS outside the State of Nevada, did not deprive the public of a full
and fair opportunity to comment on both proceedings. The public comment
period on the Yucca Mountain EIS was initiated in July of 1999, lasted
for 199 days, and included 21 public hearings, 10 of which were held
within Nevada.
Several comments received by DOE did not directly address this
notice of proposed rulemaking, but dealt with other aspects of DOE's
civilian radioactive waste program. For example, several commenters
expressed dissatisfaction with the disposal of spent fuel and high-
level waste in a geologic repository, raised claims of limited federal
authority over Yucca Mountain, criticized the nation's dependence on
nuclear power, and raised concerns about the transportation of high-
level waste and spent nuclear fuel to a repository. Many of these
comments were similar to those raised during the public comment period
on the 1996 proposal to amend the guidelines. As explained in response
to public comments on that, many of these comments are outside the
scope of this rulemaking. DOE recognizes that there are strong
differences of opinion on these matters of public policy. But DOE's
responsibility in this proceeding is to determine how best to carry out
Congress' directive in section 113(b) of the NWPA to develop criteria
for evaluating the suitability of Yucca Mountain as a potential site
for a repository for nuclear waste, not to reexamine disputes whose
resolution Congress has specified--as would be required were DOE to
respond to the broader public policy comments. Accordingly, presented
below is DOE's response to the major issues emerging from the public
comments and questions directly related to the supplemental notice.
A. The Statutory Basis and Regulatory Need for Part 963
Several commenters, including representatives of the State of
Nevada, asserted that DOE's legal rationale for revising the guidelines
was flawed and in violation of the NWPA, and that there is no statutory
or legal basis for the proposed amendments. In support of this
position, many commenters noted, among other things, that section
112(a) of the NWPA directs DOE to promulgate guidelines for the
recommendation of sites for a repository, not merely for site
characterization; that the substantive requirements of section 112(a),
such as the use of qualifying and disqualifying factors and
consideration of transportation impacts, must be part of any site
suitability criteria proposed by DOE; that Congress' failure to direct
DOE to revise its guidelines in the 1987 Amendments Act and the 1992
Energy Policy Act is an indication that Congress did not believe the
guidelines required modification; and that the intent of section 112(a)
was to require DOE to evaluate sites based on geology (e.g., natural
barriers), and not engineered barriers (e.g., waste package design).
Several commenters also noted that it was premature to revise the
guidelines since the EPA and NRC have not yet finalized their
regulations regarding a repository at Yucca Mountain and that, in any
event, there is no requirement that the guidelines closely conform to
the EPA and NRC regulations.
DOE also received comments in support of the statutory and
regulatory need for the revisions to part 960 and
[[Page 57317]]
the establishment of Yucca Mountain-specific-suitability criteria.
Those comments noted that the proposed revisions to the guidelines are
legally appropriate and timely under the NWPA; that there is no
statutory connection between the content of the section 112(a)
guideline requirements and the content of the section 113(b)
suitability criteria; that there is no need to establish site
suitability criteria in a rulemaking proceeding; and that DOE
appropriately is updating its site suitability criteria to comport with
current scientific understanding and regulatory revisions proposed by
the EPA and NRC.
As explained in detail in the SUPPLEMENTARY INFORMATION under the
section III. A, entitled, ``Legal Authority and Necessity to Amend the
Guidelines and Criteria,'' and in section III. B, above, DOE believes
that there is a sound statutory and regulatory basis upon which to
revise part 960 and promulgate part 963. DOE believes that this
rulemaking effectively harmonizes the statutory language and purposes
of relevant sections of the NWPA and the 1992 Energy Policy Act with
the current state of scientific and technical understanding of how best
to evaluate the performance of a geologic repository, as well as with
the revised regulatory framework governing the public health and safety
and licensing of a repository at Yucca Mountain. While DOE does not
believe there was any misrepresentation of the statutory language of
section 112(a) of the NWPA, as some commenters asserted, minor
modifications were made in the background section and section III above
of the Supplemental Information to avoid any confusion.
As previously stated, the approach DOE elected to take in 1984 to
implement section 112(a) and formulate the 960 guidelines was
understandable at that time, when DOE anticipated the need to evaluate,
by comparison, multiple characterized sites under section 113 leading
to the selection of one site under section 114, and the NRC licensing
regulations were premised on a demonstration of both system and
subsystem performance requirements. In the supplemental notice of
proposed rulemaking and in this notice, DOE has discussed in detail the
numerous intervening events, of a regulatory, technical and legislative
nature, that necessitated DOE's revisions to the 960 guidelines and the
need to add a new part 963 to establish the site suitability criteria
and methodology to be used in assessing the suitability of the Yucca
Mountain site.
Several commenters correctly note that Congress has not changed the
language of the NWPA in section 112(a), despite opportunities for such
change in the 1987 Amendments and the 1992 Energy Policy Act.
Congressional silence on this point is hardly dispositive, however. As
previously noted, there is no explicit language or direction in section
112 that requires or directs DOE to use the 112(a) guidelines as the
criteria to assess the suitability of a characterized site under
section 113(b). Therefore, the failure of Congress to revise section
112 has no particular bearing here.
Other commenters stated that it seems specious to argue that
Congress meant the 112(a) guidelines, including the requirement of
qualifying and disqualifying factors, to be abandoned once a site was
designated for site characterization, and that any suitability
guidelines must include qualifying and disqualifying factors. But that
is not the argument DOE has advanced. Rather, DOE's view is that
Congress did not legislate at all regarding whether DOE should or
should not use the section 112(a) guidelines for site suitability, but
did require DOE's suitability evaluation to revolve around the
potential licensability of the site. Hence, when the NRC modified its
licensing criteria in such a way as to focus on system rather than
subsystem performance, DOE could no longer use guidelines that were
inconsistent with that approach.
We also note that in this final rule, DOE is not abandoning the
concept embodied in section 112(a) that a site should be evaluated
based on such criteria as the geology, hydrology and geophysics of the
site. Nor is DOE inappropriately accounting for engineered barriers in
setting site suitability criteria under the NWPA. Table 2, VI. B of
this SUPPLEMENTARY INFORMATION provides a crosswalk between the section
112(a) geologic considerations and the criteria for evaluating site
suitability in part 963. In addition, section 113 directs DOE to engage
in activities related to developing waste form and packaging designs
and describing the relationship between the waste form and the geologic
medium. Thus, those barriers are also appropriately included in the
criteria for assessing the suitability of a repository at Yucca
Mountain. As is necessary, DOE has articulated the site suitability
criteria in a manner that is consistent with the technical and
analytical approach in the applicable EPA and NRC regulations for a
geologic repository at Yucca Mountain.
Moreover, as explained above, DOE interprets the language in
section 113(b)(1)(A)(iv), referring to section 112(a), to mean that
only the procedural requirements of section 112(a) should be followed
in setting the criteria for site suitability under section 113(b). The
inclusion of qualifying and disqualifying factors is in the nature of a
substantive requirement of the guidelines promulgated under section
112(a); it is not a statutory requirement for the establishment of
suitability criteria under section 113(b)(1)(A)(iv). In addition, DOE
does not believe that it is reasonable or necessary to retain explicit
qualifying and disqualifying conditions in the present site suitability
guidelines. Such conditions do not comport with either the revised
regulatory framework established for a repository at Yucca Mountain,
nor the current state of scientific and technical understanding of how
best to evaluate the performance of a repository. Accordingly, DOE has
established site suitability guidelines that are reasonable and fully
consistent with the mandates of the NWPA.
In response to other comments regarding the allegedly premature
nature of this rulemaking, DOE believes that the rulemaking is timely
and not premature. Although the NRC and EPA regulations were in
proposed and not final form at the issuance of the proposed rulemaking
on part 963, DOE deemed it necessary and appropriate to initiate the
process for promulgating this rule in advance of the finalization of
the EPA and NRC regulations. It was necessary to initiate the
rulemaking process in order to allow sufficient time to obtain public
review and comment, and NRC concurrence on the rule, prior to the time
of a possible DOE site recommendation then planned for mid-2001. In
addition, it was appropriate to initiate the process since the EPA and
NRC proposed regulations provided sufficient substance to enable DOE to
formulate its proposed rulemaking and solicit public comment on that
rulemaking. By initiating the process in this manner, DOE did not
intend, nor did it preclude, the option that DOE might reopen the
comment period for this rulemaking as necessary to accommodate changes
from the proposed to final rules of the EPA and NRC. DOE has reviewed
the final rules of EPA and NRC, and determined that reopening the
comment period on part 963 is not necessary. As explained in the
description of the final rule (section VI of this SUPPLEMENTARY
INFORMATION), the changes made to 963 from the draft to final stage
have been made for purposes of clarity and conformance with final 63;
the changes are not
[[Page 57318]]
substantive and do not change the basic structure, intent or analyses
performed pursuant to the rule.
Furthermore, DOE has fully explained in the supplemental notice and
this notice the reasons why it is necessary and reasonable for DOE to
conform its suitability criteria and methodology with the NRC licensing
criteria and EPA standard, in accordance with the NWPA. As illustrated
in Table 1 of this notice of final rulemaking, DOE does not believe
that the 960 guidelines are substantively consistent with the newly
developed EPA and NRC rules, thereby necessitating the amendments
promulgated today.
B. The Proposed Rules Use (or Allow the Use of) Engineered Barriers To
Compensate for the Inadequacies of the Site
Several commenters stated that the proposed rule inappropriately
allows the use of engineered barriers to compensate for inadequacies in
the performance of the natural system. Certain of these commenters
suggested that the NWPA, in particular section 112(a), prohibits
reliance on the performance of engineered barriers in evaluating the
suitability of a site for a repository system, reasoning that the
performance of the repository must rely solely on the performance of
the natural barriers.
As explained above, DOE does not believe that the provisions of the
NWPA limit or prohibit DOE's investigation and use of engineered
barriers to assess the suitability of siting a geologic repository at
Yucca Mountain. Section 113(b)(1)(B) of the NWPA directs DOE to
describe the waste packages and waste forms to be used and their
relation to the geology of the site; section 113(c) restricts DOE
activities conducted under section 113 to those necessary to provide
data required for a repository construction authorization application
to the NRC (and to comply with NEPA). In turn, section 121(b)(1)(B)
requires the NRC, in setting licensing criteria for a repository, to
provide for the use of a system of multiple barriers in the design of
the repository. In this context, multiple barriers means engineered and
natural barriers. Thus, DOE believes that the NWPA, as originally
enacted and as amended, contemplates that any site undergoing
characterization for possible development as a repository would include
investigation of, and reliance on, multiple barriers--natural and
engineered barriers.
Indeed, the NRC's original repository licensing requirements, 10
CFR part 60, made clear that the use of both natural and engineered
barriers would be required for repository licensing. Nevertheless, the
NRC was also concerned, at the time of the promulgation of part 960 in
1984, that DOE not use engineering barriers to compensate for
deficiencies in any comparison of candidate sites. The NRC, through its
concurrence process on the original part 960 guidelines, required DOE
to make clear that engineered barriers would not constitute a
compensating measure for deficiencies in the geologic media during site
screening. This was accommodated by provisions at 10 CFR 960.3-1-5 that
address comparisons of the sites in the basis for site evaluations.
That provision states that comparisons of sites shall be structured so
that engineered barriers are not relied upon to compensate for
deficiencies in the geologic media. Furthermore, it states that
engineered barriers shall not be used to compensate for an inadequate
site; mask the innate deficiencies of a site; disguise the strengths
and weaknesses of a site and the overall system; and mask differences
between sites when they are compared. (emphasis added). In its final
decision to concur in 10 CFR part 960, the NRC noted that the revisions
made to 960.3-1-5 showed that DOE would not select sites where
engineered barriers must be used to compensate for deficiencies in the
geologic media (49 FR 28136).
At present, DOE is not in a situation of comparing multiple sites
for possible development as a repository. Part 963 applies only to a
determination of the suitability of the Yucca Mountain site for
possible development as a repository. Importantly, absent in NRC's
current requirements for licensing, 10 CFR part 63, and in NRC's
concurrence on this rule, are any requirements that DOE demonstrate
repository performance based solely on natural barriers.
The NRC expects that, in any licensing proceeding for a repository
at Yucca Mountain, DOE will demonstrate that the natural barriers and
the engineered barrier system will work in combination to enhance the
overall performance of the geologic repository. NRC regulations require
an engineered barrier system in addition to the natural barriers
provided by the geologic setting, and that natural barriers and the
engineered barrier system work in combination to enhance the resiliency
of the geologic repository and increase confidence that the postclosure
performance objective at 10 CFR 63.113(b) will be achieved.
NRC's expectation is shared by the EPA, and other oversight
entities. In 40 CFR part 197, EPA defines the Yucca Mountain disposal
system as the combination of underground engineered and natural
barriers at the Yucca Mountain site that prevents or substantially
reduces releases from the disposed radioactive material, and emphasizes
the importance of engineered barriers as a method, within human
control, to delay the release of radionuclides from the repository.
Oversight entities, such as the NWTRB and the NRC's Advisory Committee
on Nuclear Waste, have been consistent in their recommendations to
pursue robust, long lived waste packages to protect the health and
safety of the public.
In consideration of this information, DOE incorporated in its
proposal specific criteria to address the performance of the engineered
components of the repository system. The Department believes that the
criteria are consistent with the Congressional intent in the NWPA, and
the regulatory expectations of the EPA and the NRC, that there be
performance contributions from both the natural and engineered
barriers. DOE does not believe that reliance on such barriers would
mask or compensate for inadequacies in the natural system, but rather,
such barriers enhance and prolong the ability of the natural system to
contain, and mitigate the rate of release of, individual radionuclides.
C. The Rules Should Not Be Changed To Fit the Site
1. The Site Would Be Disqualified Under Existing Guidelines
Several commenters stated their belief that Yucca Mountain would be
disqualified under the existing guidelines and, on that basis, DOE is
attempting to change the rules to fit the site. This same comment was
made in response to DOE's 1996 proposal to amend part 960. The primary
reason for this comment, then as now, is the argument that the site
cannot meet the disqualifying condition in 960.4-2-1(d) pertaining to
groundwater travel time. Many commenters also questioned what condition
would disqualify the site under part 963, and how far contaminated
groundwater may travel under part 963.
As stated in the preamble to the supplemental notice of proposed
rulemaking (64 FR 67071), DOE's reasons for amending the guidelines are
not based on a belief or finding that the Yucca Mountain site would be
disqualified if the 960 guidelines were applied without amendment. With
respect to groundwater travel time, the Department continues to
evaluate
[[Page 57319]]
groundwater movement and other hydrological properties of the site to
assess the performance of a repository at Yucca Mountain. Based on the
results of the 1998 Viability Assessment and ongoing evaluations, the
Department believes there is no basis at this time to find that
conditions that would disqualify the site if 10 CFR part 960 were
applied, exist at Yucca Mountain.
With regard to the question of what condition would disqualify the
Yucca Mountain site, part 963 requires the Secretary of Energy to
evaluate the suitability of the site based on the likelihood that a
repository at the site could meet the applicable radiation protection
standard. Accordingly, if the Secretary determines this requirement
cannot be met, the site may not be determined suitable by the Secretary
and thus would be ``disqualified'' for consideration for further
development. With regard to the question of how groundwater travel time
will be assessed under part 963, groundwater flow and transport will be
analyzed as suitability criteria, section 963.17(a)(7), unsaturated
zone flow and transport, and section 963.17(a)(8), saturated zone flow
and transport. Accordingly, groundwater flow and transport will
continue to be studied for their role in repository performance and the
ability of the site to meet applicable radiation protection standards.
2. DOE Is Changing the Rules in the Middle of the Game
Several commenters claimed that DOE is inappropriately establishing
suitability guidelines as a result of ongoing site characterization
work, instead of setting the guidelines in advance of that work. In
that regard, one commenter questioned whether the guidelines would
affect the design of the repository. Stated otherwise, DOE understands
the concern to be that it is perceived as setting guidelines to meet a
specific repository design or other site characteristic, rather than
setting guidelines based on predetermined criteria for repository
design or other site characteristics.
DOE has explained previously, however, that the reason it is
issuing these guidelines now is based on events beyond its control that
have made its prior guidelines an inappropriate tool for evaluating
suitability. Under the NWPA, suitability is linked to licensability.
Congress's decisions to change the NWPA to focus on Yucca Mountain and
to direct the EPA and NRC to revise their standards bearing on
licensability set in motion a chain of regulatory changes to the
licensing rules that in turn necessitated this rulemaking.
DOE also notes that the fact that the final site suitability
guidelines are being issued now, instead of earlier in the site
characterization process, is to the public's advantage, since they
reflect the most recent developments in regulatory requirements and
standards and technical understanding. For example, the guidelines are
structured to evaluate repository performance against a set of criteria
potentially important to waste isolation. The repository design,
although not directly affected by the guidelines, will be structured to
take advantage of the features of the natural and engineered barriers
that are important to waste isolation.
Moreover, DOE's current approach is consistent with earlier
opinions expressed by the National Academy of Sciences, Board on
Radioactive Waste Management (Board). In its report, Rethinking High-
Level Radioactive Waste Disposal (1990), the Board addressed this issue
and discussed the relative merits of an approach that presets technical
criteria for evaluation of a repository site versus an approach that
remains flexible and responsive to data and information as it is
developed. In that report, the Board criticized the U.S. high-level
waste program for its approach, at that time, of defining in advance
the technical requirements for every part of the multi-barrier system,
and in its emphasis on the geologic component of the barrier. The Board
opined that the better approach, consistent with geologic and mining
practice, is to remain flexible instead of setting rigid predefined
goals. The Board observed that, instead of trying to anticipate all the
complexities of a natural geologic environment, the better approach
would be to define the goal broadly in ultimate performance terms,
rather than anticipatory requirements, so that increased knowledge can
be incorporated in the design at a specific site.
D. The Part 963 Guidelines Would (a) Mask the Degree of Safety, Which
Can Lower or Eliminate Public Confidence, and (b) Lower, or Eliminate
the Degree of Safety
(a) Some commenters believed that the proposed revisions, that is,
the use of a total system performance assessment instead of individual,
subsystem requirements, mask the degree of safety of the site. These
commenters felt that the TSPA method, with its heavy reliance on
computer modeling, is too uncertain and subject to mishandling to form
the basis for assessing the safety of the site and ensuring public
confidence in the resulting assessment. Other commenters expressed the
view that use of the TSPA method is appropriate. One commenter, Nye
County, Nevada, commented that the criteria provide for greater
transparency and verifiability than DOE's initial proposed amendments
to part 960 in 1996, and that the TSPA approach is preferred to DOE's
previous consideration of site-specific revisions to the 960
guidelines.
As explained in other sections of this notice of final rulemaking,
the prevailing view in the relevant scientific community supports use
of the TSPA method to assess and evaluate expected performance of a
geologic repository over thousands of years. This is the evaluation
method required by the NRC and the EPA in assessing repository
performance for licensing purposes. It would be unreasonable for DOE to
establish criteria to determine the suitability of the Yucca Mountain
site that are not based on the prevailing scientific and regulatory
view of performance assessment.
Over the past several years, DOE and other entities involved in
oversight and regulation of high level waste programs have undertaken
significant efforts to make the results of total system performance
assessment calculations more transparent to non-technical audiences.
This is in response to the type of concerns expressed by the commenters
here, that the complex calculations are difficult to visualize and
verify, and, hence, may mask the degree of safety provided. While DOE
acknowledges the difficulty in comprehending TSPA for the lay person,
DOE has attempted, through this rulemaking and in other public forums,
to enhance transparency in presenting the results of TSPA and
associated complex technical calculations and modeling. For example, in
the Viability Assessment, DOE provided a detailed explanation of the
TSPA method and the computer models and technical data and information
supporting those modes. This explanation has been augmented by
presentations and other briefings provided by DOE to oversight agencies
and other members of the public.
One of DOE's primary considerations in drafting and finalizing this
rulemaking was to make the TSPA process and method more transparent and
verifiable. As explained in the Viability Assessment, transparency is
manifested through the ease of a reader in understanding the process by
which a study was carried out, which assumptions are driving the
results, how they were arrived at, and the rigor of the
[[Page 57320]]
analyses leading to the results. Transparency is achieved when a reader
can understand what was done in the analyses, what the outcome was, and
why. Part 963, at sections 963.16(b)(1), (5), (6), (7), and (9),
provides a framework for the listed system performance assessment that
should assist in accomplishing this end.
Additionally, confidence in the results of the performance
assessment calculations can be enhanced if the presentation
illustrates: (1) The system's expected evolution, as defined by the
spatial and temporal response of the system to waste emplacement; and
(2) the uncertainty in the system's expected evolution and the
significance of that uncertainty to the system performance goals. Part
963 incorporates these kind of considerations under 963.16(b)(2), (3),
(8), (9), (10), and (12).
Further, section 963.17 lists criteria that reflect both the
processes and the models that are important to the total system
performance. Those criteria are expressly identifiable and traceable
components of the TSPA, thereby increasing transparency and
traceability of the results. In addition, DOE intends to make available
to the public the documentation underlying any TSPA analyses and
results. With this material, the public will have an opportunity to
review the technical information and data underlying the analyses
supporting the postclosure performance assessment.
(b) Some commenters expressed the view that the use of TSPA, and
the lack of qualifying or disqualifying subsystem requirements, would
lower or eliminate the degree of safety.
Part 963 is structured to align DOE's site suitability
determination with the EPA public health and safety standard, as
implemented by the NRC regulations, and to base a suitability
determination on the likelihood that the site could meet applicable
radiation protection standards. Through Congressional direction, EPA
modified the basis for a public health and safety standard from a
release-based standard to a health-effects standard. In turn, Congress
directed the NRC to conform its licensing regulations to the EPA
standard and implement that standard. Both regulators predicate a
demonstration that the standard can be met on the use of performance
assessment.
DOE is in agreement with the Congress, the National Academy of
Sciences, the EPA and the NRC that a dose-based standard, that
explicitly limits the risk of adverse health effects and considers
health effects to the potentially affected public, is an appropriate
basis upon which to assess public health and safety. Further, DOE
believes that the risk or dose approach provides additional and better
protection to the health and safety of the public in the vicinity of
Yucca Mountain than the release based approach reflected in the 960
guidelines. The part 963 guidelines explicitly require DOE to consider
health effects to the public in the vicinity of the Yucca Mountain
site. Under the part 960 guidelines, the DOE would only have been
required to calculate releases from the repository, not the potential
health effects. Hence, the part 963 guidelines enhance the degree of
safety provided to the public in the vicinity of the Yucca Mountain
site, rather than lowering it.
E. The Appropriateness of the Proposed Criteria
One commenter questioned the postclosure criteria proposed by DOE
stating that the criteria were simply a list of physical
characteristics with no bases for the discrimination that would be
necessary for a suitability determination, while other commenters
supported the Department's proposal indicating that the proposed
postclosure criteria were appropriate for decisionmaking.
As DOE noted in its supplemental notice of proposed rulemaking, we
believe we may properly opt to use one dictionary definition of
criteria as ``characterizing traits'' rather than the other possible
definition ``benchmarks'' or ``pass-fail standards.'' This is because,
among other reasons, section 112(a) of the NWPA uses the term ``primary
criteria'' synonymously with the term ``detailed geologic
considerations,'' a term that is more naturally understood as
``characterizing traits'' than ``benchmarks.'' Although the specific
section 113 criteria addressed herein are different from the specific
``primary criteria'' referred to in section 112(a), it seems likely
that Congress used the word ``criteria'' in both places to have the
same general meaning, i.e., ``considerations'' rather than
``benchmarks.'' In addition, we believe the ``characterizing traits''
definition is more plausible where what is at issue are criteria that
are part of a site characterization effort, as 113(b) specifies.
In discussing this definition of criteria in the proposed rule, DOE
noted that criteria are not necessarily quantitative. To illustrate
this point, DOE pointed to NRC's Quality Assurance criteria, found then
in Appendix B of 10 CFR part 50 (now incorporated into final part 63,
subpart G). NRC was concerned that this may have mischaracterized the
importance and nature of the NRC requirements by noting that they are
not expressed as quantitative, pass-fail standards. We agree that our
discussion on this point was confused at best. This is partly because
the two definitions of criteria, ``benchmark'' versus ``characterizing
trait,'' represent a continuum as well as a dichotomy. NRC's Appendix B
QA criteria and the suitability criteria of sections 963.14 and 963.17
resemble each other in that they are non-quantitative. But NRC's QA
criteria are also benchmarks, in that a QA plan must have them and
describe how they will be satisfied to pass muster. In that respect
they differ from the part 963 criteria.
Accordingly, the sentence in the Supplementary Information
describing the suitability criteria should have read as follows: ``For
example, in 10 CFR part 63, Subpart G, the NRC sets forth quality
assurance ``criteria'' that are factors that must be present, including
a description of how they will be satisfied, for DOE's QA program to be
judged adequate. However, although these QA criteria are required
factors, they are not, nor do they contain, quantitative, pass-fail,
benchmark standards.''
F. DOE Should Consider Preclosure Issues, Including Environmental,
Socioeconomic, and Transportation Issues
Several commenters objected to DOE's exclusion in part 963 of
certain 960 preclosure guidelines such as environmental quality,
socioeconomics and transportation, on the basis that section 112(a) of
the NWPA requires consideration of those factors, along with qualifying
or disqualifying conditions for those factors. Additionally, several
commenters questioned where such topics would be addressed, and
expressed their belief that the draft Yucca Mountain EIS did not fully
or adequately address those topics.
As previously explained, DOE does not agree that the site
suitability criteria established under section 113(b) must be the same
as the guidelines promulgated under section 112(a). Part 963
establishes the criteria and methodology for determining the
suitability of the site under section 113(b)(1)(A)(iv) as part of DOE's
site characterization activities and site characterization plan. Since
1988 and the publication of the Site Characterization Plan, DOE has
indicated that information relative to socioeconomics, transportation
and environmental quality guidelines referred to in part 960 would be
[[Page 57321]]
obtained through means other than site characterization activities.
Accordingly, DOE does not agree that socioeconomics, transportation and
environmental quality must be included in part 963 as criteria to
determine the suitability of the site under section 113(b).
DOE agrees that socioeconomics, environmental quality and
transportation are appropriate factors for the Secretary to consider in
determining whether to recommend the Yucca Mountain site for
development. As stated in the rule and in this notice, those factors
and other relevant information that will be considered in any
Secretarial recommendation under section 114 of the NWPA will be
addressed by DOE through other mechanisms in which the public will also
have the opportunity to participate, such as the Yucca Mountain EIS
process. While some commenters may be critical of the adequacy of the
Yucca Mountain EIS analysis, or the extent of coverage, DOE believes
that the 960 guidelines on socioeconomics, transportation and
environmental quality are appropriately addressed in the Yucca Mountain
EIS. DOE is in the process of evaluating public comments on the draft
Yucca Mountain EIS, including those comments submitted under this
rulemaking. Upon completion of the EIS, DOE believes that coverage of
these factors will be fully adequate for consideration in any
Secretarial site recommendation.
G. DOE Should Define the Margin by Which it Will Meet the Radiation
Protection Standard, or the Way in Which it Will Meet the Standard
At least one commenter suggested that DOE should be more definitive
or restrictive for the determinations to be made in section 963.12,
preclosure suitability, and section 963.15, postclosure suitability.
Specifically, it was suggested that DOE be more definitive or clarify
what is meant by the phrase ``likely to meet'' in those sections, such
as specifying the mean result of the TSPA calculation as the basis for
a determination of postclosure suitability.
DOE does not believe it is useful to be more definitive or
restrictive regarding the phrase ``likely to meet.'' By this phrase DOE
is indicating, as it must, that site suitability is largely a DOE
judgment call as to the likelihood that the site will qualify for a
license from the NRC for repository construction. This determination is
not the equivalent of a license application by DOE, nor is it the
equivalent of an NRC determination that a license application will be
successful. Under the circumstances, DOE believes this phrase
accurately captures the level of information and confidence required by
the Secretary to make a suitability determination. With regard to the
comment that DOE should use only the mean result of the TSPA to judge
the likelihood of meeting the standard, DOE believes more than the mean
result would be appropriate in estimating the ability to meet licensing
regulations. Under NRC regulations, 10 CFR subpart 63.101, DOE must
demonstrate, at the time of licensing, reasonable assurance (for the
preclosure period) and reasonable expectation (for the postclosure
period) that the performance objectives can be met. This requirement
necessitates that DOE develop and provide more than just the mean
result in demonstrating compliance with the standard. Therefore, the
use of ``results'' is appropriate for the suitability assessment under
sections 963.12 and 963.15, instead of something more singular, such as
a mean or expected result only.
In addition, some commenters noted that the rule should require
performance in excess of the standard; stated otherwise, that DOE
should specify a margin or level of confidence regarding performance
results. This same comment was made in response to the 1996 proposed
rulemaking. DOE has reconsidered this comment here, but nevertheless
maintains the same response as provided in response to comments on the
1996 proposal. That is, DOE does not believe it is appropriate or most
effective to specify or quantify a level of confidence or margin of
safety as part of the rule. The public, as well as the Secretary of
Energy, will have access to data and information underlying the TSPA
analyses and supporting analyses. This information will include the
probabilistic distribution of values around the expected value, in
order to assess the level of confidence in the performance calculation.
H. Whether DOE Should Revoke the Guidelines in 10 CFR Part 960 in
Making the Site Suitability Determination for the Yucca Mountain Site
or Continue To Use Them in Addition to Part 963
DOE proposed amendments to modify part 960 so that it would apply
only to competitive site selection for the purpose of nominating sites
for site characterization activities. Opinion about this part of the
November 30, 1999, proposal was divided. Some commenters argued for
complete revocation of part 960 because it embodies a methodology for
site comparisons that is: (1) obsolete; (2) inconsistent with
internationally accepted practice; and (3) inconsistent with currently
proposed NRC and EPA rules for the Yucca Mountain site. Other
commenters disagreed, arguing that the sub-system approach in part 960
can and should be applied in addition to the rules for total system
performance assessments in part 963. They viewed the provisions of part
960 as a viable and better method than proposed part 963 for assessing
the suitability of the Yucca Mountain site for the location of a
nuclear waste repository.
With regard to the comments favoring complete revocation of part
960, DOE does not think that reaching final conclusions on their
continued utility for competitive selection of sites for site
characterization is appropriate for two reasons. First, the 1987
amendments to the Nuclear Waste Policy Act of 1982 require DOE to focus
its efforts exclusively on evaluation of Yucca Mountain. Second, if
there is ever a need to return to competitive selection of sites for
site characterization, that would be the time to replace part 960 with
a methodology that reflects scientific advances since part 960 became
effective in 1984, as well as then applicable statutory and regulatory
requirements.
With regard to commenters who favored application of the subsystem
requirements of part 960 in addition to part 963, DOE thinks that this
approach is scientifically unsound and impossible to carry out. As
explained at length above, the subsystem methodology of part 960 is
scientifically unsound because it largely ignores the crucial
interactions of various features, events, and processes that should be
determinative. In DOE's view, reliance on the methodology of part 960
would result in conclusions that are too likely to be erroneous. Even
if the subsystem methodology of part 960 were a scientifically sound
basis for evaluating site suitability, DOE could not use it in
evaluating suitability for licensing because of the NRC's revisions to
its licensing regulations. In the notice of supplemental proposed
rulemaking, DOE included a table, reproduced above (Table 1), which
sets forth the cross references in part 960 to the NRC's part 60 and
demonstrates the lack of any substitutable cross reference to the NRC's
part 63. The table was accompanied by a narrative exploring the
groundwater guidelines in particular to show the impossibility of
applying them after the NRC substituted part 63 for part 60. None of
the commenters
[[Page 57322]]
disputed this table, and in DOE's view, it shows continued use of part
960 in the evaluation of the Yucca Mountain site is not a viable
option.
I. Response to NRC Comments
a. Coordination With NRC
NRC made the comment that proposed part 963 did not address the
potential matter of a conflict between the proposed DOE regulation and
the applicable NRC regulations. NRC recommended that DOE explain how it
would address this matter in this statement of consideration.
NRC correctly noted that proposed part 963 did not contain a
provision expressly requiring NRC regulations to take precedence in the
event of a conflict or inconsistency between the DOE regulations and
NRC regulations. DOE does not believe such a provision is necessary,
given the nature and structure of part 963. Moreover, DOE believes this
provision could create confusion in the implementation of the DOE
regulation, since it suggests that in certain circumstances not
presently identified DOE would need to substitute an NRC regulation for
its own.
DOE recognizes that its site suitability guidelines must assist the
Secretary in judging the ability of the Yucca Mountain site to meet
licensing requirements, pursuant to section 113(c) of the NWPA, but
that the license application process, over which NRC has jurisdiction,
is distinct and separate from the Secretary's judgment regarding site
suitability. Accordingly, part 963, which is specific to the Yucca
Mountain site, is carefully crafted to conform to pertinent parts of
the NRC's part 63, the NRC's licensing requirements specific to the
Yucca Mountain site, that serve DOE's need for assessing the
suitability of the site as a basis for a possible site recommendation.
Under this structure, the necessary consistency between the DOE and NRC
regulations is obtained during the drafting of the DOE regulation. Any
conflicts between the DOE and NRC regulations have been resolved
through the NRC concurrence process on the regulation.
b. Quality Assurance
The NRC also commented that DOE should recognize in the preamble to
part 963 the importance and role of quality assurance in DOE site
characterization activities, and the expected pedigree of the technical
information and data underlying the suitability determination.
As the NRC acknowledges in its comments, the Department expects to
use essentially the same data for both its site suitability
determination and any potential license application, even though the
site suitability determination is not the equivalent of a determination
that the site will meet all the requirements needed to obtain a
construction authorization under NRC regulations. DOE acknowledges that
the site suitability determination must be based on credible and
verifiable data and information, and that assurance of the quality of
that data and information is a factor in that determination. Therefore,
due consideration will be given by the Department to any outstanding
quality assurance issues that may affect the pedigree of technical
information underlying the part 963 suitability determination.
c. Definition of Cladding
In response to a comment from the NRC that the proposed definition
of cladding found at 10 CFR subpart 963.2 conveyed an inaccurate notion
that all cladding is corrosion resistant, the Department has modified
the proposed definition as follows: cladding is the metallic outer
sheath of a fuel rod element; it is generally made of a corrosion
resistant zirconium alloy or stainless steel, and is intended to
isolate the fuel from the external environment. Also, the Department
has clarified the use of the term cladding in section VI(B)(h)(2) of
this SUPPLEMENTARY INFORMATION, and in the rule at section
963.17(a)(5)(i).
J. Response to Nuclear Waste Technical Review Board Comments
The NWTRB provided comments on the 963 rulemaking, noting several
considerations for DOE to address in its suitability guidelines. The
NWTRB endorsed the use of performance assessment in support of a site
suitability determination, but also noted that additional lines of
argument and evidence should be used. In particular, the NWTRB
supported use of other lines of evidence such as safety margins,
defense-in-depth, performance confirmation, consideration of disruptive
process and events, and reference to insights from natural and man-made
analogs noting that such topics were addressed in revision 3 of the
report, ``Repository Safety Strategy: Plan to Prepare the Postclosure
Safety Case to Support Yucca Mountain site Recommendation and Licensing
Considerations'' (``Repository Safety Strategy'') (TRW-WIS-RL-000001,
January 2000). The NWTRB emphasized that understanding uncertainties in
the performance assessment analysis is a critical component to attain
technical credibility and sound decisionmaking. In that regard, the
NWTRB recommended that DOE include in its representation of performance
uncertainty: (a) A description of critical assumptions; (b) an
explanation of why particular parameter ranges were chosen; (c) a
discussion of possible data limitations; (d) an explanation of the
basis and justification for using expert judgments; (e) an assessment
of confidence in the conceptual models used; and (f) identification and
quantification of uncertainties associated with the performance
estimates.
DOE agrees with much of the NWTRB's comments and recommendations.
In fact, part 963, in its proposed and final form, is addressed to
eliciting much of the information and analysis the NWTRB recommends and
that was identified in revision 3 of the Repository Safety Strategy.
Under section 963.16(b), DOE will conduct TSPAs in a manner to satisfy
twelve enumerated conditions. Those conditions correspond to a large
degree with the specific recommendations of the NWTRB repeated above,
and provide the additional lines of evidence and argument beyond the
performance assessment calculations. DOE structured this section of the
rule to correspond to NRC's licensing regulation, particularly sections
63.114 and 63.115. To clarify this point, DOE added language to the
description of this rule, in section VI of this SUPPLEMENTARY
INFORMATION, to better articulate how the additional lines of evidence
and other recommendations will be accounted for in the suitability
determination. Presented below is additional explanation of how the
NWTRB's comments are addressed in part 963.
The additional lines of evidence and argument recommended by the
NWTRB are addressed in section 963.16(b), except for performance
confirmation. DOE believes that performance confirmation is important,
and will develop a performance confirmation plan in conjunction with
the licensing process. DOE will provide in the underlying documentation
of the TSPA calculation, performed in accordance with section
963.16(b), the ``margin'' by which the expected performance of the
repository exceeds the applicable radiation protection standards.
Although DOE does not agree that it is necessary to quantify or specify
the margin of safety as part of the rule, information and data about
the margin will be available to decision-makers for review and
consideration in reaching a suitability determination. Under sections
963.16(b)(8), (9), and (10), DOE
[[Page 57323]]
will identify and evaluate multiple and independent barriers to waste
isolation, thereby providing information on defense-in-depth.
Disruptive processes and events are analyzed and included in the TSPA
under sections 963.16(b)(4) and (5), and are express criteria of
suitability in section 963.17(b). Insights from natural and man-made
analogs are also analyzed and included in the TSPA under section
963.16(b)(7), which requires DOE to provide the technical basis for the
TSPA models, including comparisons made with empirical observations,
such as natural analogs.
The other specific NWTRB recommendations, described above, are also
addressed in part 963. NWTRB recommendation (a), describe critical
assumptions, is addressed by section 963.16(b)(2), regarding accounting
for uncertainties and variabilities in parameter values; section
963.16(b)(3), regarding consideration of alternative models of features
and processes and evaluation of the effects of the alternative models;
and section 963.16(b)(12), regarding conduct of appropriate sensitivity
analyses. In addition, the analyses and documentation underlying the
TSPA will contain an explanation of assumptions to assure the quality
of the information.
NWTRB recommendation (b), explain why particular parameter ranges
are chosen, is addressed by section 963.16(b)(1), regarding data
related to the postclosure suitability criteria, and section
963.16(b)(2), regarding an accounting of uncertainties and
variabilities in parameter values and identification of the technical
basis for parameter ranges, probability distributions, and bounding
values.
NWTRB recommendation (c), include a discussion of possible data
limitations, is addressed by section 963.16(b), regarding explanation
of the technical bases of the data and models (e.g., sections
963.16(b)(2), (3), (5), (6), (7), and (10)). For example, section
963.16(b)(6) states that DOE will provide the technical basis for
either inclusion or exclusion of degradation, deterioration, or
alteration processes of engineered barriers. This will entail a
discussion of possible data limitations.
NWTRB recommendation (d), provide an explanation of the basis and
justification for using expert judgment, is included in the portions of
section 963.16(b) regarding explanations of technical bases (e.g.,
sections 963.16(b)(2), (5), (6), (7), and (10)). In those explanations,
DOE will explain where expert judgment has been used.
NWTRB recommendation (e), provide an assessment of confidence in
the conceptual models used, is addressed by sections 963.16(b)(3) and
(5). Under those sections of the rule, DOE will consider alternative
models of features and processes and their effects on performance, and
provide the technical basis for either inclusion or exclusion of
specific features, events and processes (FEPs) of the geologic setting.
In essence, these analyses will help DOE and others to assess the
validity of the conceptual models and estimates of the significance of
those models to repository performance.
NWTRB recommendation (f), identify and quantify the uncertainties
associated with the performance estimates, is addressed by sections
963.16(b)(2), (3), (5), (6), (7), (9) and (10). Under these provisions,
DOE will identify and quantify uncertainties associated with the
performance estimates.
V. Description of Final Rule--10 CFR Part 960
A. Subpart A--General Provisions
This section of the Guidelines contains the statement of
applicability and definitions. The final revisions to section 960.1,
Applicability, limit the application of the Guidelines to evaluations
of the suitability of sites for site characterization under section
112(b) of the NWPA. The revisions eliminate the applicability of the
Guidelines to determinations of suitability of a site at the site
characterization stage under section 113, or the site recommendation
stage under section 114. These revisions clarify that the applicability
of the Guidelines is limited to the preliminary site screening stage,
which entails a comparative analysis process. The final revisions to
the third and fourth sentences update the reference to other regulatory
requirements of the NRC and EPA, in light of the current status of
applicable NRC and EPA regulations relative to high-level waste
geologic repositories. The fifth through seventh sentences remain
unchanged.
The final revisions to the definitions section make the terms
consistent with the NWPA and with the other revisions to the Guidelines
limiting applicability of subparts B, C, and D of the Guidelines to
determinations of site suitability for site characterization under
section 112 of the NWPA.
B. Subpart B--Implementation Guidelines
The final revisions to the implementation guidelines limit the
procedures and basis for application of the postclosure and preclosure
guidelines of subparts C and D, respectively, to evaluations of the
suitability of sites for site characterization.
Section 960.3, entitled implementation guidelines, is revised to
eliminate the sentences in that section setting forth the procedures
and basis for application of subparts C and D in evaluations and
determinations of the suitability of a site under section 113 and
section 114 of the NWPA. These revisions remove section 960.3-1-4-4,
Site Recommendation for Repository Development, in its entirety. That
section pertained to procedure and evidence for making a site
recommendation decision under section 113 and 114. The part 960
guidelines are no longer relevant to those decisions and therefore
reference to them is removed. Section 960.3-1-5, entitled Basis for
Site Evaluation, is revised to eliminate all references to Appendix III
in making suitability determinations at the site characterization or
site recommendation stages. Only the last sentence of section 960.3-2,
Siting Process, is revised. This revision limits the applicability of
the siting process to the recommendation of sites for site
characterization. Section 960.3-2-4, Recommendation of Sites For the
Development of Repositories, is removed in its entirety. These
paragraphs pertain to the comparison of characterized sites, leading to
a recommendation by the Secretary to the President of a site for
development as a repository. The final revisions eliminate that
decision process from evaluation under the Guidelines, and the section
in its entirety is removed.
C. Appendix III
The final revisions to Appendix III remove and eliminate the
applicability of this Appendix to decisions for repository site
selection and siting decisions. The qualifying and disqualifying
conditions of the technical guidelines in subparts C and D now apply
only to the decision point for selecting sites for site
characterization. All references to the site selection and site
recommendation decisions under sections 113 and 114 are removed,
including the tabular column in Appendix III referencing the repository
site selection siting decision.
With respect to the Guidelines listed in Appendix III that apply to
environmental quality, socioeconomics and transportation
considerations, DOE considered whether to continue to require their
applicability to a Yucca Mountain site recommendation under section 114
of the NWPA. DOE decided not to do so because the issues
[[Page 57324]]
addressed by these Guidelines will be substantially covered in the
environmental impact statement for the Yucca Mountain site, and section
114(a)(1)(D) requires that the final environmental impact statement be
part of the comprehensive statement of the basis for a site
recommendation to the President (42 U.S.C. 10134(a)(1)(D)).
Opportunities for public comment on the analysis of environmental
quality, socioeconomics and transportation issues have been provided as
part of the public review and comment process on the draft
environmental impact statement. In sum, DOE believes that the
environmental quality, socioeconomics and transportation guideline
requirements are substantially and unnecessarily duplicative of
requirements under the procedures for developing an environmental
impact statement and for formulating and informing a site
recommendation under section 114.
VI. Description of Final Rule--10 CFR Part 963
The purpose of this part of the Supplementary Information is to
explain the meaning and basis for those provisions of the final part
963 that are not self-explanatory and to identify and explain the main
changes in the rule from proposed to final. The following is a section
by section analysis of the final rule.
A. Subpart A--General Provisions
Subpart A comprises two parts, the statement of Purpose, section
963.1, and Definitions, section 963.2.
(a) Purpose--section 963.1. The purpose of the final rule is as
stated in this section: to establish the methods and criteria to help
guide DOE's determination regarding the suitability of the Yucca
Mountain site for the location of a geologic repository. The
suitability evaluation methods in question are consistent with the
methods the NRC has promulgated for assessing whether a geologic
repository at the Yucca Mountain site meets licensing criteria and
requirements. The suitability criteria allow for evaluation of the
geologic considerations derived from section 112(a) and reflect the
current scientific understanding and regulatory expectations (both NRC
and EPA) regarding the performance and safety of a geologic repository
during the preclosure and postclosure periods of operation. Because the
suitability criteria are part of the site characterization program,
these criteria relate to site characterization activities. Site
characterization activities relate to scientific and technical
investigations of the site to determine its natural properties and
features, for example, studying the geohydrology and geochemistry of
the site, as distinct from consideration of other factors, such as
cost, socioeconomics and transportation of waste to the repository. An
explanation of how the suitability criteria were derived is provided
below.
It should be noted that the final rule does not address the site
recommendation process in its entirety. Suitability is only one aspect
of the Secretary's recommendation. Section 114(a)(1) of the NWPA sets
out other information not addressed by this rule that the Secretary
must consider, some of which the Secretary must submit to the President
and make available to the public if the Secretary recommends the site
for development as a geologic repository. Section 114(a)(1)(G) also
indicates that the Secretary has discretion to base his recommendation
on ``such other information as the Secretary considers appropriate.''
Finally, we note that the guidelines established by this rule are
just that: guidelines. Their function is to assist the Secretary in
reaching a conclusion concerning a question that is quintessentially
predictive and requires the exercise of judgment: how a repository that
has not yet been built will function thousands of year in the future.
The purpose of these guidelines is to make tools and information
available to the Secretary to assist him in reaching this judgment, not
to cabin his discretion in doing so.
(b) Definitions--section 963.2. The final rule includes definitions
of certain words and terms. The definitions clarify DOE's intent and
meaning in the context of this rule. The definitions are also intended
to make the terms consistent with the NRC regulations governing the
construction and licensing of a repository at the Yucca Mountain site.
Several of the terms are important to understanding the suitability
evaluation process, and are addressed here.
Applicable radiation protection standard has been added to the
definitions section to clarify use of the phrase in the rule. By
applicable radiation protection standard, DOE means the numerical
radiation dose or concentration limits contained within 10 CFR part 63,
specifically identified in our definition. Those NRC-regulatory
provisions in turn incorporate the public health and environmental
standards promulgated by the EPA in 40 CFR part 197. These are the same
standards compliance with which DOE will have to demonstrate during
licensing.
The numeric radiation dose limits applicable in the preclosure
period refer to the numerical dose limits in 10 CFR 63.111(a) and (b)
and 63.204. Subpart K of 10 CFR part 63 contains the preclosure public
health and environmental standards, adopted from 40 CFR part 197. The
preclosure standard will require DOE to demonstrate at licensing that
there is reasonable assurance no member of the public in the general
environment (i.e., outside the Yucca Mountain site, the Nellis Air
Force Range and the Nevada Test Site) will receive more than an annual
dose of 15 mrem from the management and storage of radioactive material
inside the Yucca Mountain repository and outside the repository but
within the site (10 CFR part 63.204).
In addition, the preclosure performance objectives contained in
part 63.111(a)(2) will require DOE to demonstrate at licensing that
there is a reasonable assurance that during normal operations any
radiation exposures and releases of radioactive materials to any real
member of the public outside the Yucca Mountain site are within the
numerical radiation dose limits contained in part 63.204 and a related
NRC regulation, 10 CFR part 20, specifying radiation protection
standards for workers and the public involving NRC licensees. The
performance objectives also include numerical guides for design of the
geologic operations area (10 CFR part 63.111(b). The numerical guides
will require DOE to demonstrate at licensing that it has designed the
geologic repository operations area in such a manner that there is
reasonable assurance that aggregate radiation exposures and aggregate
releases of radioactive material will be within prescribed dose limits
during Category 1 event sequences and that any single Category 2 event
sequence will be within prescribed limits.
The numeric radiation limits applicable in the postclosure period
refer to the numerical dose limits in 10 CFR 63.311 and 63.321, and the
numeric radionuclide concentration limits in 10 CFR 63.331. The
postclosure public health and environment standards are contained in
Subpart L of 10 CFR 63, and are comprised of three separate standards.
First, the individual protection standard, at 10 CFR 63.311, requires
DOE to demonstrate at licensing, using performance assessment, that
there is a reasonable expectation that for 10,000 years following
disposal, the reasonably maximally exposed individual receives no more
than an annual dose (total effective dose equivalent) of 15 mrem
[[Page 57325]]
from releases from the undisturbed Yucca Mountain disposal system.
Second, the human intrusion standard, at 10 CFR 63.321, requires DOE to
determine the earliest time that the waste package would degrade
sufficiently that a human intrusion could occur without recognition by
the drillers. If DOE determines that complete waste package penetration
will occur at or before 10,000 years, then DOE will have to demonstrate
at licensing, using performance assessment, that there is a reasonable
expectation that the repository will meet the individual protection
standard of no more than an annual dose of 15 mrem to the reasonably
maximally exposed individual 10,000 years following disposal. If
complete waste package failure occurs after 10,000 years, then DOE must
include the results of the analysis indicating the exposures to the
reasonably maximally exposed individual at the time it occurs in the
environmental impact statement for Yucca Mountain as an indicator of
long-term disposal system performance. Third, the ground water
standard, at 10 CFR 63.331, requires DOE to demonstrate at licensing
that there is a reasonable expectation that for 10,000 years of
undisturbed performance after disposal, releases of specified
radionuclides from waste in the Yucca Mountain disposal system into the
accessible environment will not cause the level of radioactivity in the
representative volume of ground water to exceed certain limits. The
limits for radionuclide concentrations in the representative volume of
ground water are provided in Table 1 of part 63.331, and specify a
limit of 4 mrem per year to the whole body or any organ from combined
beta and photon emitting radionuclides, and limits of 5 picocuries per
liter for combined radium-226 and radium-228 (including natural
background) and 15 picocuries per liter of gross alpha activity
(excluding radon and uranium).
Barriers are defined as any material, structure or feature that
prevents or substantially reduces the rate of movement of water or
radionuclides from the Yucca Mountain repository to the accessible
environment, or prevents the release or substantially reduces the
release rate of radionuclides from the waste. Several examples of a
barrier are provided, e.g., a geologic feature and engineered
structure, or a waste form with physical and chemical characteristics
that significantly decrease the mobility of radionuclides. This
definition of barrier is slightly different from the definition in
proposed part 963, which was based on the definition in proposed part
63. The NRC modified its definition in final part 63.2 to be consistent
with EPA's definition of barrier in 40 CFR 197.12. DOE is now modifying
its definition of barrier to be consistent with the final NRC
definition at part 63.2.
The definition adopted here differs from the NRC definition only in
regard to the phrase ``for a period to be determined by the NRC.'' This
phrase is in the final NRC definition, but has not been included in
part 963. The NRC clarified this aspect of the definition stating the
description of each barrier includes the information on the time period
over which each barrier will perform its intended function including
any changes during the compliance period. Under part 963.16(b), DOE's
performance assessment analyses will include descriptions of barriers,
both natural and engineered, that are important to isolating
radioactive waste. Those descriptions will include information on the
time period over which the barriers will perform their intended
functions, including any changes during the compliance period.
Therefore, DOE believes it is not necessary to adopt this phrase in its
definition of barrier for purposes of DOE's assessment of the
suitability of the Yucca Mountain site.
Criteria are defined as those characterizing traits that are
relevant to assessing the performance of a geologic repository at the
Yucca Mountain site. The criteria will allow for evaluation of the
impact of those geologic considerations identified in section 112(a) of
the NWPA that are relevant to the assessment of the performance of a
geologic repository at the Yucca Mountain site. The geologic repository
includes the natural barriers of the geologic setting and the
engineered barriers of the repository design. The suitability criteria
of the final rule are specific characterizing traits of the Yucca
Mountain site that, through the site characterization process, DOE has
identified as important indicators of the performance of the total
repository system (that is, the integrated natural and engineered
barrier systems).
Consistent with varying definitions in standard dictionaries, DOE
considered defining the term ``criteria'' as benchmark, pass-fail
standards rather than as ``characterizing traits.'' DOE decided not to
adopt the ``pass-fail'' definition for two reasons. First, in section
112(a) of the NWPA, the term ``primary criteria'' is used synonymously
with the term ``detailed geologic considerations,'' which are more
naturally understood as ``characterizing traits'' than as
``benchmarks.'' Although, as explained above, the section 113 criteria
are not the same as the section 112 criteria, it seems likely Congress
used the same words in a similar general sense to mean ``characterizing
traits'' in both places (rather than ``characterizing traits'' in
section 112 and ``benchmarks'' in section 113). Second, under section
113(b), the suitability criteria are to be included in the site
characterization plan. This further suggests they are better understood
as ``characterizing traits.'' If a point be made of it, however, the
proposed and final part 963 rule also contain a benchmark for the
site's suitability. Section 963.11 states that the Secretary may find
the site suitable if he concludes, using the evaluation methods set out
in other portions of the rule, that it is likely to meet the applicable
radiation protection standards set by the EPA and contained in the
NRC's licensing rules. Hence even if section 113(b) is read to require
the Secretary to establish benchmarks that the site must meet to be
found suitable, he has done that as well.
DOE's proposed rule contained a somewhat confused discussion of the
relationship of NRC's use of the word ``criteria'' in its QA program to
the interpretation we give it here. That discussion was confused
because it conflated ``benchmark'' and ``quantitative,'' thereby
suggesting that NRC's non-quantitative criteria were therefore also not
benchmarks. We clarify that confusion in our response to comments in
section IV of this SUPPLEMENTARY INFORMATION, and reiterate here that
our prior statement should have read as we state it there.
During the postclosure period, DOE will evaluate the performance of
the total system using a computer modeling tool called total system
performance assessment. For clarity and consistency with the NRC's
final rules, the definition of total system performance assessment has
been changed to match the definition of performance assessment in 10
CFR 63.2. DOE views the change in definition as a clarifying,
nonsubstantive change, as the series of analyses that are encompassed
within DOE's definition of total system performance assessment, or
performance assessment as defined by the NRC, are the same. Total
system performance assessment identifies the features, events and
processes that might affect the performance of the Yucca Mountain
disposal system, as well as their probabilities and significance. Total
system performance assessment examines the effects of those features,
events and processes on that
[[Page 57326]]
performance by estimating the mean annual dose to the reasonably
maximally exposed individual, including associated uncertainties, as a
result of releases from the Yucca Mountain disposal system.
DOE has added or modified other definitions associated with
analyses conducted for the postclosure period either to conform 963 to
10 CFR 63 or to make nonsubstantive clarifications. The definitions of
engineered barrier system and reference biosphere have been modified to
be consistent with the NRC's definitions in part 63.2. Some new
definitions have been also added to conform to part 63. For example,
the terms Yucca Mountain disposal system, reasonably maximally exposed
individual, and human intrusion have been added to the definition
section of part 963 and are the same definitions as provided in 10 CFR
63.2. Other parts of the 963 rule which reference these terms, e.g.,
the definition of total system performance assessment (963.2) and the
postclosure suitability evaluation method (963.16), have been updated
to reflect these new terms.
For the preclosure period, DOE will evaluate suitability using a
preclosure safety evaluation method. The preclosure safety evaluation
will consider site characteristics and preliminary engineering
specifications to assess the adequacy of the repository facilities to
perform their intended functions and to mitigate the effects of
initiating events and event sequences that could affect the ability of
the geologic repository operations area to operate safely.
In part 63, the NRC clarified certain titles and descriptions of
the analyses to be performed for the preclosure period. The preclosure
objectives and performance analysis requirements in parts 63.111(a) and
(b) and 63.112 are stated in terms of analyzing ``initiating events and
event sequences,'' rather than ``design basis events,'' to determine
radiation exposures and releases in the preclosure time period within
the geologic repository operations area. Accordingly, DOE has deleted
the definition of design basis event in part 963.2 and added
definitions of design bases, event sequence, initiating event, and
geologic repository operations area. These definitions track those used
by the NRC in its final rule, and therefore, DOE considers these
changes to be conforming, nonsubstantive changes to part 963 that leave
the analytical requirements for the preclosure safety evaluation the
same in substance.
Under these new definitions, the geologic repository operations
area refers to the high-level radioactive waste facility that is part
of a geologic repository, including both surface and subsurface areas,
where waste handling activities are conducted. To add clarity to the
rule, DOE has deleted the term repository support facilities and
incorporated it into the term surface facilities, to match the usage of
the term surface facilities within part 963.13, the preclosure
suitability evaluation method.
Event sequence is defined as a series of actions and/or occurrences
within the natural and engineered components of a geologic operations
area that could potentially lead to exposure of individuals to
radiation. Event sequences include one or more initiating events, and
are categorized in two ways: (1) Those events, both natural and human-
induced, that are expected to occur one or more times before permanent
closure (i.e., Category 1 event sequences); or (2) those events, both
natural and human-induced, that have at least one chance in 10,000 of
occurring before permanent closure (i.e., Category 2 event sequences).
The preclosure safety evaluation will assess the ability of the
geologic repository operations area to meet the applicable radiation
protection standard for the preclosure period under both categories of
event sequences.
DOE's evaluation of the suitability of a geologic repository at the
Yucca Mountain site will be based on consideration of a preliminary
design for the geologic repository. The design is the description of
the potential geologic repository, which includes multiple barriers to
the release and transport of radionuclides. These multiple barriers
consist of both the natural barriers and an engineered barrier system.
The geologic repository includes not only the facilities and areas
where radioactive wastes are handled, but also that portion of the
geologic setting that provides isolation of the radioactive wastes. As
used in the final rule, and in NRC's part 63, isolation means
inhibiting the movement of radioactive material from the repository to
the location where the reasonably maximally exposed individual resides,
so that postclosure radiation doses and radiation concentrations will
not exceed the limits prescribed in NRC's regulation.
B. Subpart B--Site Suitability Determination, Methods and Criteria
(a) Scope--section 963.10. Subpart B describes, for both the
preclosure and postclosure periods, various facets of DOE's suitability
determination for the Yucca Mountain site. There are separate sections
of the final rule for the preclosure and postclosure time periods.
These sections also describe the site suitability criteria DOE will
apply in accordance with section 113(b) of the NWPA, the methods it
will use in applying the criteria and evaluating suitability, and the
way it will reach the resulting suitability determination.
The final rule is divided into two sections corresponding to the
preclosure and postclosure periods, and within each period, three
subsections. The subsections present for each period: (1) The
suitability determination; (2) the suitability evaluation method; and
(3) the criteria to be used for the evaluation. The preclosure and the
postclosure periods are addressed separately because DOE will use
different approaches to each arising out of the different
considerations relevant to the suitability of a geologic repository
during these two periods. This separation is consistent with the
structure of DOE's prior Guidelines, and the structure of the original
and revised NRC licensing regulations, which also have separate
performance objectives for the preclosure and the postclosure periods.
The preclosure method and criteria will guide DOE's evaluation of the
suitability considerations that deal with the operation of the
repository before it is closed, while waste is being received, stored
and emplaced. They also allow for the possibility of retrieval. These
are the considerations important in protecting the public and
repository workers from exposures to radiation during repository
operations, especially if an accident should occur. The postclosure
method and criteria will guide DOE's evaluation of the suitability
considerations that deal with the long-term behavior of the repository.
The behavior of interest here is after waste emplacement and repository
closure.
(b) Suitability determination--section 963.11. This section
describes how DOE will determine the suitability of the site based on
the information and data developed through the program of site
characterization activities at Yucca Mountain. DOE may find the Yucca
Mountain site suitable for the location of a repository based on its
determinations relative to the preclosure and postclosure suitability
evaluations under sections 963.12 and 963.15. Those determinations, in
turn, entail assessment of preclosure and postclosure suitability using
the designated evaluation method and criteria for each time period. The
overall suitability determination, if affirmative, will be one part of
the Secretary's decision, under section 114 of the NWPA, whether or not
to recommend the Yucca Mountain site to the
[[Page 57327]]
President for development of a repository.
(c) Preclosure suitability determination--section 963.12. The
suitability evaluation of the Yucca Mountain site will consider the
safety of the geologic repository during the operational or preclosure
time period. The preclosure criteria to evaluate the suitability of a
geologic repository operations area at Yucca Mountain will be
considerations that are important to determining safety during
construction and active operation and to demonstrating compliance with
the applicable radiation protection standard.
(d) Preclosure suitability evaluation method--section 963.13. The
preclosure suitability criteria will be applied through a preclosure
safety evaluation method. The preclosure safety evaluation will guide
the evaluation of the suitability of the site with respect to
preclosure operations. The NRC provides a framework indicating how to
conduct this type of evaluation in 10 CFR part 63.112. DOE designed the
preclosure safety evaluation method in this final rule based on this
NRC framework and a DOE assessment of what information would be useful
to determine, at the site suitability stage, whether or not a proposed
geologic repository at Yucca Mountain is likely to meet the applicable
radiation protection standards for the preclosure period.
The preclosure safety evaluation method, using preliminary
engineering specifications, will assess the adequacy of the repository
facilities to perform their intended functions and prevent or mitigate
the effects of postulated event sequences. The preclosure safety
evaluation will consider: a preliminary description of the site
characteristics, the surface facilities, and the underground
facilities; a preliminary description of the design for the operating
facilities and a preliminary description of any associated limits on
operation; a preliminary description of potential hazards (for example,
seismic activity, flooding and severe winds), event sequences, and
their consequences; and a preliminary description of the structures,
systems, components, equipment, and operator actions intended to
mitigate or prevent accidents. The purpose of the preclosure safety
evaluation is to help assess whether relevant hazards that could result
in unacceptable consequences have been adequately evaluated and
appropriate protective measures have been identified, so as to help
determine whether the geologic repository operations area is likely to
comply with the preclosure requirements for protection against
radiation exposures and releases of radioactive material.
The preclosure safety evaluation will emphasize performance
requirements, analytical bases and technical justifications, and
evaluations that show how safety functions will be accomplished. The
adequacy of the facility design will be evaluated by consideration of
postulated event sequences viewed as sufficiently credible that the
facility should be designed to prevent or mitigate their effects. Event
sequences are those natural and human-induced events that are either
expected to occur before closure, or have one chance in 10,000 of
occurring before permanent closure.
(e) Preclosure suitability criteria--section 963.14. DOE will
evaluate the suitability of the Yucca Mountain site during the
preclosure period using the following criteria: (a) Ability to contain
and limit releases of radioactive materials; (b) ability to implement
control and emergency systems to limit exposures to radiation; (c)
ability to maintain a system and components that perform their intended
safety functions; and (d) ability to preserve the option to retrieve
wastes during the preclosure period. These criteria are considerations
important to determining the performance of a potential repository at
Yucca Mountain during this preclosure period. For example, the first
criterion will help assess whether repository facilities are capable of
keeping the radioactive materials confined in order to limit releases
of radioactive material. The second and third criteria help assess
whether emergency controls and procedures have been developed that are
adequate to limit releases should an accident occur, and whether the
system and its components will perform their safety function as
intended. The fourth criterion, the capability to retrieve or recover
the wastes from the repository should conditions warrant, is also
plainly relevant to the safe functioning of a repository.
These criteria will allow for evaluation of the impact of those
geologic considerations derived from section 112(a) of the NWPA that
are relevant to the preclosure period. These considerations are
hydrology, geophysics, seismic activity, atomic energy defense
activities, proximity to water supplies and proximity to populations.
These considerations are relevant to the evaluation of preclosure
suitability because they bear on the evaluation of repository system
safety during the preclosure period. The hydrology and geophysics of
the site are important to preclosure safety because they are indicators
of possible initiating events for accidents. Seismic activity is also
important in this regard, as it is an indication of the potential for
earthquake activity to disrupt normal functioning of a repository
surface facility. The location of atomic energy defense activities in
relation to the Yucca Mountain site is important to preclosure safety
and would be considered to the extent these activities exist and may
impact operations of the repository facility. Proximity to water
supplies and proximity to populations are important to preclosure
safety because they relate to potential locations where people could
eventually be exposed to radionuclides either through airborne
transport or through a water pathway.
(f) Postclosure suitability determination--section 963.15. The
postclosure suitability evaluation of the Yucca Mountain site will
consider the safety of the geologic repository during the time after
operations cease, the postclosure period. DOE will determine the
suitability of the Yucca Mountain site for the postclosure period by
examining the results of a TSPA conducted under section 963.16. If the
results indicate a repository at Yucca Mountain is likely to meet the
applicable radiation protection standard, then DOE may determine, on
the basis of site characterization activities, that the site is
suitable for the postclosure period.
(g) Postclosure suitability evaluation method--section 963.16. DOE
will evaluate the suitability of a potential repository at the Yucca
Mountain site using the TSPA method (described in greater detail
below). Using the TSPA method, DOE will estimate quantitatively the
mean annual dose to the reasonably maximally exposed individual and the
level of radioactivity in the representative volume of ground water
over the compliance period (10,000 years). With these estimates, DOE
will evaluate the performance of the repository and its ability to
limit radiological exposures within the applicable radiation protection
standard.
(1) Section 963.16(a). Section 963.16(a) describes how DOE will
conduct separate performance assessments in order to evaluate the
postclosure performance of a geologic repository at Yucca Mountain. One
TSPA will be conducted in accordance with the method described in
963.16(b), using the criteria identified in section 963.17, and
assuming no human intrusion into the repository (i.e., an undisturbed
Yucca Mountain disposal system). A separate TSPA will be
[[Page 57328]]
conducted in accordance with the method described in part 963.16(b)
(except not all engineered and natural barriers will be considered),
using the criteria in section 963.17, and assuming a human intrusion
into the repository in accordance with the scenario specified in 10 CFR
63.322 and the conditions of the human intrusion standard specified in
10 CFR part 63.321. This section of 963.16(a) has been modified from
its proposed form to add clarity to the evaluation process in light of
changes in the NRC regulations governing the human intrusion standard
and associated analyses. The results of each performance assessment
will be examined by DOE to determine the suitability of the site for
the postclosure period.
The conduct of separate assessments is consistent with 40 CFR part
197 and 10 CFR part 63. The EPA and NRC regulations, in turn, are based
on NAS recommendations in the report, Technical Bases for Yucca
Mountain Standards, on how best to assess the performance and
resilience of a potential repository. Because the manner and likelihood
of human intrusion occurring many hundreds or thousands of years into
the future cannot be estimated reliably by examining either the
historic or geologic record, the NAS recommended an approach that will
assess how resilient the geologic repository would be against a
postulated intrusion. The consequences of the assumed human intrusion
event will be addressed in a ``stylized'' manner, that is, by assuming
a particular human intrusion event occurs in a certain way. DOE will
conduct the human intrusion analysis, and use the results of the
performance assessment, in the manner set out in the NRC regulations
(e.g., parts 63.321 and 63.322).
(2) Section 963.16(b). Section 963.16(b) provides an outline of the
contents and manner in which DOE will conduct its performance
assessments. As described previously in this notice, and briefly
summarized here, performance assessment in this context is a method of
forecasting how a system or parts of a system designed to contain
radioactive waste will behave over time. Its goal is to aid in
determining whether or not the system can meet established performance
requirements. A TSPA is a type of performance assessment analysis in
which the components of a system are integrated or linked into a single
analysis.
The TSPA addresses both the engineered and natural system
components. The engineered system is to some extent controllable, but
the natural system generally is not. The responses of the total system
extend over periods beyond those for which data have been or can be
obtained. The relationship of the components of a TSPA is often
described as a pyramid. The lowest level of the pyramid represents the
complete suite of process and design data and information (that is,
field and laboratory studies that are the first step in understanding
the system). The next higher level indicates how the data feed into
conceptual models that portray the operation of the individual system
components. The next higher level represents the synthesis of
information from the lower levels of the pyramid into computer models.
The term abstraction often is used to indicate the extraction of
essential information from large quantities of data. The TSPA models
are usually referred to as abstracted models. At this point, the
subsystem behavior may be described by linking models together into
representations; this is the point at which performance assessment
modeling is usually thought to begin. This is also the basis for the
identification of the Yucca Mountain specific suitability criteria
contained in the final rule.
The upper level is the final level of distillation of information
into the most significant aspects to represent the total system. At
this point, the models are linked together. These are the models used
to forecast system performance and estimate the likelihood that the
performance will comply with regulations and ensure long-term safety.
As information flows up the pyramid, it generally is distilled into
progressively more simplified or essential forms, or becomes more
abstracted. However, abstraction is not synonymous with simplification.
If a particular component model cannot be simplified without losing
essential aspects of the model, then the model becomes part of the TSPA
calculation tool. Thus, an abstracted model in a TSPA may take the form
of something as simple as a table of values that were calculated using
a complex computer model, or the abstraction may take the form of a
fully three dimensional computer simulation.
The TSPA method described in section 963.16(b) is a systematic
analysis that identifies the features, events, and processes (i.e.,
specific conditions or attributes of the geologic setting, degradation,
deterioration, or alteration processes of engineered barriers, and
interactions between the natural and engineered barriers) that might
affect performance of the Yucca Mountain disposal system; examines
their effects on performance; and estimates the mean annual dose to the
reasonably maximally exposed individual and the radionuclide
concentrations in the representative volume of water. The features,
events, and processes considered in the TSPA will represent a wide
range of effects on system performance. According to EPA and NRC
regulations, those features, events, and processes expected to affect
compliance significantly or be potentially adverse to performance are
included, while events of very low probability (less than one chance in
10,000 of occurring within 10,000 years of disposal) should be excluded
from the analysis. The annual dose to the reasonably maximally exposed
individual is estimated using the selected features, events, and
processes, and incorporating the probability that the estimated dose
will occur.
The TSPA that will be used to assess the postclosure performance of
the Yucca Mountain repository will be conducted in the manner described
in section 963.16(b). It will synthesize data and information into a
set of models that simulate the behavior of the individual system
components. DOE will abstract essential information from its initial
models and refine them into linked models, including computer models,
that represent important aspects of system performance. DOE will use
these models to forecast system behavior and the likelihood of system
compliance with the applicable radiation protection standard.
The TSPA method described in section 963.16(b) contains twelve
enumerated conditions DOE will satisfy in conducting the TSPA for the
postclosure suitability determination. Those conditions will provide
DOE with multiple lines of argument and evidence in support of the
resultant TSPA calculation. For example, as part of the TSPA
calculation, DOE will consider disruptive processes and events,
identify and evaluate multiple barriers to waste isolation, produce
information relative to the margin by which the site will meet the
applicable radiation protection standard, and include analysis of
insights from man-made analogs. Development of this information will
build confidence in the TSPA result and aid decision-makers in reaching
a suitability determination. Through documentation of the technical
basis for much of the analysis, DOE will identify and quantify
uncertainties associated with the performance estimates, explain and
describe the critical assumptions used and possible data limitations,
and identify the areas
[[Page 57329]]
where expert judgment and natural analogs were used in the analyses.
The TSPA calculations will be used to address conditions in the
natural and engineered components of a Yucca Mountain disposal system
over the time that the standards apply. The TSPA calculations will also
be used to consider disruptive events that are improbable, but that are
important to understanding the repository behavior in the future. To
prepare the TSPA, DOE will identify those natural features of the
geologic setting and the design features of the engineered barrier
system that are considered barriers important to waste isolation. TSPA
will be used to assess the capability of the barriers identified as
important to waste isolation to isolate waste, taking into account
uncertainties in characterizing and modeling the barriers. By
conducting these analyses and documenting the technical basis for them,
DOE will account for multiple and independent barriers to waste
isolation. DOE notes that in final 10 CFR part 63, the NRC reorganized
its requirements pertaining to analysis of multiple barriers by
creating a new section, part 63.115, to reflect these requirements.
These requirements, although presented in a new section, are not
substantively different from proposed part 63 and do not require a
change to part 963. The TSPA will also include and consider information
derived from the performance of various sensitivity studies.
Sensitivity studies and the regulatory definition of very unlikely
events will provide the technical basis for inclusion or exclusion of
specific features, events, and processes of the geologic setting in the
TSPA.
Specific features, events, and processes of the geologic setting
will be evaluated through sensitivity analyses to determine if the
magnitude and time of the resulting annual dose would be significantly
changed by their omission. Sensitivity analysis is a technique that is
used to examine how a system responds if one of its components is
changed. Systems are said to be sensitive to such a component if the
results of the calculation are changed significantly in response to
changes in that component's values. The sensitivity calculations will
also provide the technical basis for either inclusion or exclusion of
degradation or alteration processes of engineered barriers in the TSPA.
Degradation or alteration processes will be evaluated further if the
magnitude and timing of the resulting expected annual dose would be
significantly changed by their omission.
Using the TSPA results, DOE can examine the sensitivity of one or
more components of the calculations in the assessment. DOE can examine
the response of the geologic repository system with regard to
sensitivities of the system to the suitability criteria, in order to
evaluate whether or not the geologic repository meets the applicable
radiation protection standard.
As part of the TSPA, DOE will account for uncertainties and
variabilities in both calculations and data, and provide the technical
bases for parameter ranges, probability distributions, and bounding
values. This accounting will enable DOE to identify critical
assumptions, address uncertainties in those assumptions, and understand
possible data limitations. The reason for this accounting is that it is
recognized, by the NRC and others, that there are inherent
uncertainties in the understanding of the evolution of the geologic
setting, biosphere, and engineered barrier system. DOE will evaluate
compliance and the performance of the potential repository using
sophisticated, complex predictive models that are supported by data
from field and laboratory tests, site-specific monitoring, and natural
analog studies that may be supplemented with expert judgment.
Another aspect of DOE's conduct of the TSPA is the analysis of
alternative models of features and processes. Under part 963.16(b)(3),
DOE will consider alternative models of features and processes that are
consistent with available data and current scientific understanding,
and evaluate the effects that alternative models would have on the
estimated performance of the geologic repository. These analyses will
help DOE and others assess the validity of the conceptual models and
estimates of the significance of those models to repository
performance. In this regard, if other interested persons suggest and
present to DOE alternative models that are consistent with available
data and current scientific understanding, DOE will evaluate those
other models. DOE does not believe, however, that it would be
scientifically or technically useful, and may be administratively
burdensome, to require that, in every case, DOE provide the bases for
not using an alternative model suggested by another party. However, DOE
may decide, on a case-by-case basis, to document consideration of
alternative models that were suggested by other interested persons, but
not used because, among other things, the model is not consistent with
available data and current scientific understanding.
(h) Postclosure suitability criteria--section 963.17. The
postclosure criteria to evaluate the suitability of a geologic
repository at Yucca Mountain will be considerations that reflect both
the processes that are important to the total system performance of the
geologic repository and the models used to simulate those processes.
These criteria are characterizing traits that are relevant and
important in the processes to be modeled in the TSPA that DOE will use
in evaluating the suitability of the Yucca Mountain site for the
postclosure period. These criteria also allow for evaluation of the
impact of those geologic considerations derived from section 112(a) of
the NWPA that are relevant to the postclosure period. Following is a
description of how the section 112(a) geologic considerations relate to
the postclosure suitability criteria, as well as a discussion of the
criteria as they relate to the processes and computer models to be used
in evaluating the performance of a geologic repository in the
postclosure period.
(1) Section 112(a) geologic considerations. The geologic
considerations derived from section 112(a) of the NWPA that are
relevant to the postclosure performance of a repository at Yucca
Mountain are: hydrology, geophysics, seismic activity, proximity to
water supplies, and proximity to populations. These considerations are
relevant to postclosure performance because they affect components and
processes of the repository system related to potential transport of
radionuclides via ground water to members of the public.
Hydrology- and geophysics-related conditions are relevant because
they describe some of the geologic features of the site that are
related to safety and the physical characteristics that are related to
potential transport of radionuclides to the biosphere. Seismic activity
is relevant to postclosure performance because it is related to the
potential for changes in geologic structures that could lead to
enhanced transport of radionuclides. Proximity to water supplies and
populations are relevant to postclosure performance because they are
related to potential locations where people could eventually be exposed
to radionuclides in their water.
Table 2 provides a cross-reference between the geologic
considerations derived from section 112(a), and the postclosure
suitability criteria. As previously stated, the postclosure suitability
criteria largely represent the process model components of the total
system performance assessment that DOE will use to evaluate the
performance of the repository during the
[[Page 57330]]
postclosure period. DOE has identified these processes as pertinent to
assessing the performance of a repository at Yucca Mountain through
information and data developed under its site characterization program.
One of the considerations found in section 112(a), location of
natural resources, is no longer addressed through a site suitability
criterion, and instead is addressed through the separate performance
assessment provision, part 963.16(a)(2). Proposed part 963 included a
criterion for inadvertent human intrusion, which was related to the
consideration under section 112(a) of the location of valuable natural
resources, because that is a factor that could lead to human intrusion
through exploratory drilling or excavation and a consequent breach of
the repository's safety barriers. Because this factor will be addressed
through a separate performance assessment provision, part 963.16(a)(2),
which requires assessment of potential human intrusion events in a
manner consistent with NRC regulations governing a human intrusion
standard and event scenario, DOE does not believe it is necessary to
retain this suitability criterion in final part 963.
Table 2
[Postclosure]
------------------------------------------------------------------------
NWPA Sec. 112(a) geologic considerations Suitability criteria
------------------------------------------------------------------------
(a) Processes pertinent to total system performance
------------------------------------------------------------------------
Hydrology, geophysics, seismic activity.. (1) Site characteristics
Hydrology, geophysics, seismic activity.. (2) Unsaturated-zone flow
characteristics
Hydrology, geophysics, seismic activity.. (3) Near-field environment
characteristics
Hydrology, geophysics seismic activity... (4) Engineered barrier system
degradation ,
characteristics
Hydrology, geophysics, seismic activity.. (5) Waste form degradation
characteristics
Hydrology, geophysics, seismic activity.. (6) Engineered barrier system
degradation, flow, and
transport characteristics
Hydrology, geophysics, seismic activity.. (7) Unsaturated-zone flow and
transport characteristics
Hydrology, geophysics, seismic activity.. (8) Saturated-zone flow and
transport characteristics
Hydrology, proximity to water supplies, (9) Biosphere characteristics
proximity to populations.
------------------------------------------------------------------------
(b) Disruptive processes and events
------------------------------------------------------------------------
Hydrology, geophysics.................... (1) Volcanism
Seismic activity, geophysics............. (2) Seismic events
Hydrology, geophysics, seismic activity.. (3) Nuclear criticality
------------------------------------------------------------------------
(2) Suitability criteria. DOE has developed its site
characterization program to address those processes of the repository
system that are pertinent to understanding how a repository at Yucca
Mountain would be evaluated for suitability using the applicable
radiation protection standard. The program also has been developed to
better understand these processes, and resolve or put in place methods
to resolve issues related to those processes. DOE has described these
processes, and the methods to resolve issues related to the processes,
in the SCP, in semi-annual progress reports on site characterization
program activities, and in several TSPAs conducted over the years,
including the Viability Assessment. These processes are simulated
through performance assessment models; those models are integrated and
refined to a point resulting in a representation of the performance of
the system in total.
Put in simple terms, the processes that are pertinent to
understanding the performance of a repository at Yucca Mountain, and
that form the basis for the numerical models in the TSPA and the
suitability criteria in section 963.17, are those physical processes of
water falling on Yucca Mountain as rain and snow, moving into the
mountain, down through the unsaturated zone to the potential repository
level, from the repository level to the saturated zone, and from there
to the accessible environment. At the repository level, the water would
be affected by the physical processes associated with the repository
and with the waste packages and the waste forms. Eventually, the water
could move out of the repository horizon and further downward through
the unsaturated zone. Subsequently, it could move into the saturated
zone where it could be transported to a point where humans could be
exposed to any radionuclides carried in the water. Disruptive events
could potentially affect these processes and, therefore, will be
considered. This set of physical processes is simulated in the
numerical modeling method of the TSPA that will be used to assess
quantitatively the radionuclide releases to the public and,
consequently, the safety and suitability of the Yucca mountain site.
The suitability criteria presented in this final rule are derived
from these pertinent physical processes. These criteria represent the
characteristic traits pertinent to assessing the performance of a
geologic repository at the Yucca Mountain site. They also allow for
evaluation of the impact of geologic considerations derived from
section 112(a) of the NWPA such as hydrology, geophysics, seismic
activity, and proximity to water supplies and populations.
The sequence in which the suitability criteria are presented in the
final rule generally corresponds to the process of water flow presented
above. In general, the criteria can be thought of as building blocks;
each criterion in the sequence is evaluated on its own, with the
results of that evaluation incorporated into the evaluation of the
succeeding criteria, and so on until the final analysis. DOE may refine
these process models to better reflect and assess the processes
pertinent to performance of a geologic repository at the Yucca Mountain
site. It is possible that the processes, as well as the design
selected, could dictate other ways to arrange the information included
under the individual criteria. While the individual components of the
process models may vary according to improvements in data and
information, DOE's suitability determination will be based on an
evaluation of each of the postclosure suitability criteria.
The criteria are separated into two categories. The first category,
presented in section 963.17(a), represents those criteria important to
the total system performance assessment without accounting for
disruptive processes and events that could impact that performance. The
second category, presented in section 963.17(b), are those criteria
representing disruptive processes and events that could adversely
affect the characteristics of the repository system, and consequently
release radionuclides to the human environment. Each criterion in the
first category is linked to a specific TSPA model component that will
be used to evaluate the performance of that criterion. Each criterion
in the second category is generally treated as an effect imposed on the
system at a time that reflects the probability of occurrence of the
disruptive event.
Under section 963.17(a), the first and a fundamental criterion that
will be modeled to assess performance of a repository at the Yucca
Mountain site is the representation of pertinent site
[[Page 57331]]
characteristics. The criterion of site characteristics includes: (a)
The geologic properties of the site--for example, stratigraphy, rock
type and physical properties, and structural characteristics; (b) the
hydrologic properties of the site--for example, porosity, permeability,
moisture content, saturation, and potentiometric characteristics; (c)
the geophysical properties of the site--for example, thermal
properties, densities, velocities and water contents, as measured or
deduced from geophysical logs, and (d) the geochemical properties of
the site--for example, precipitation, dissolution characteristics, and
sorption properties of mineral and rock surfaces. Together, as
reflected in the performance assessment, these characteristics enable a
representative simulation of the behavior of a geologic repository at
the Yucca Mountain site.
The second criterion, unsaturated zone flow characteristics,
relates to the processes affecting the limitations and amount of water
entering the unsaturated zone above the repository and contacting
wastes in the repository. The unsaturated zone flow characteristics
include: (a) Climate--for example, precipitation and postulated future
climatic conditions; (b) infiltration--for example, precipitation
entering the mountain in excess of water returned to the atmosphere by
evaporation and plant transpiration; (c) unsaturated-zone flux--for
example, water movement through the pore spaces, or flowing along
fractures or through perched water zones above the repository; and (d)
seepage--for example, water dripping into the underground repository
openings from the surrounding rock. Together, the first and second
criteria will be used to define the temporal and spatial distribution
of water flow through the unsaturated zone above the water table at
Yucca Mountain, and the temporal and spatial distribution of water
seepages into the underground openings of the repository.
The third criterion, near field environment characteristics, also
relates to processes important to limiting the amount of water that
could contact wastes. This criterion includes: (a) Thermal hydrology--
for example, effects of heat from the waste on water flow through the
site, and the temperature and humidity at the engineered barriers; and
(b) near-field geochemical environment--for example, the chemical
reactions and products resulting from water contacting the waste and
the engineered barriers materials. The thermal regime generated by the
decay of the radioactive wastes can mobilize water over the first
hundreds to thousands of years. For these reasons, the amount of water
flowing in the rock and seeping into drifts is expected to vary with
time.
The fourth criterion, engineered barrier system degradation
characteristics, relates to the processes important to long waste
package lifetimes. This criterion includes: (a) Engineered barrier
system component performance--for example, drip shields, backfill,
coatings, or chemical modifications; and (b) waste package
degradation--for example, the corrosion of the waste package materials
within the near-field repository environment. This criterion and the
first criterion, site characteristics, define the spatial and temporal
distribution of the time periods when waste packages are expected to
breach. The thermal, hydrologic, and geochemical processes acting on
the waste package surface are the most important environmental factors
affecting the waste package lifetime. In addition, the degradation
characteristics of the waste package materials significantly affect the
timing of waste package breaches.
The fifth criterion, waste form degradation characteristics,
addresses the initial aspects of low rate of release of radionuclides.
This criterion includes: (a) Cladding degradation--for example,
corrosion or break-down of the cladding on the spent fuel pellets; and,
(b) waste form dissolution--for example, the ability of individual
radionuclides to dissolve in water that penetrates breached waste
packages. This criterion is important to understanding how and in what
manner the waste forms could break down, permitting the release of
radionuclides to the immediately surrounding environment.
The sixth criterion, engineered barrier system degradation, flow,
and transport characteristics, addresses the processes important to the
manner in which radionuclides can begin to move outward once the
engineered barrier system has been degraded. This criterion includes :
(a) colloid formation and stability--for example, the formation of
colloidal particles and the ability of radionuclides to adhere to these
particles as they may be washed through the remaining barriers; and (b)
engineered barrier transport--for example, the movement of
radionuclides dissolved in water or adhering to colloidal particles to
be transported through the remaining engineered barriers and in the
underlying unsaturated zone. This criterion and the first criterion,
site characteristics, lead to a determination of the spatial and
temporal distribution of the mass of radioactive wastes released from
the waste packages. Each characteristic depends on the thermal,
hydrologic, and geochemical conditions inside the waste package, which
change with time.
The next two criteria--unsaturated zone flow and transport
characteristics (criterion seven), and saturated zone flow and
transport characteristics (criterion eight)--relate to processes
important to radionuclide concentration reduction during transport. To
assess the movement of radionuclides away from the degraded engineered
barrier system, the first important process to understand is the
unsaturated zone flow characteristics in combination with the
unsaturated zone transport characteristics. The unsaturated zone flow
and transport characteristics criterion includes: (a) unsaturated-zone
transport--for example, the movement of water with dissolved
radionuclides or colloidal particles through the unsaturated zone
underlying the repository, including retardation mechanisms such as
sorption on rock or mineral surfaces; and (b) thermal hydrology--for
example, effects of heat from the waste on water flow through the site.
The next criterion, saturated zone flow and transport characteristics,
addresses similar radionuclide transport processes, only in the
saturated zone. This criterion includes: (a) saturated zone transport--
for example, the movement of water with dissolved radionuclides or
colloidal particles through the saturated zone underlying and beyond
the repository, including retardation mechanisms such as sorption on
rock or mineral surfaces; and (b) dilution--for example, diffusion of
radionuclides into pore spaces, dispersion of radionuclides along flow
paths, and mixing with non-contaminated ground water.
The ninth criterion, biosphere characteristics, addresses the
characteristics that describe the lifestyle and habits of individuals
who potentially could be exposed to radioactive material at a future
time. Because of the difficulty in predicting the lifestyles and habits
of future generations, such assessments are to be based on
representative current conditions. Both the EPA and the NRC's final
rules require DOE to apply current conditions (with consideration of
climate evolution) in assessments of the reference biosphere. This
criterion includes: (a) A reference biosphere and reasonably maximally
exposed individual defined, for example, by considering pathways,
location and behavior ; and (b) biosphere transport
[[Page 57332]]
and uptake--for example, the consumption of ground or surface waters
through direct extraction or agriculture, including mixing with non-
contaminated waters and exposure to contaminated agricultural products.
Together, the criteria of unsaturated zone flow and transport
characteristics, saturated zone flow and transport characteristics, and
biosphere characteristics, address the spatial and temporal variations
of radionuclide concentrations in ground water. The ground water
concentration ultimately yields the mass of radionuclides that may be
ingested or inhaled by individuals exposed to that ground water, which
in turn leads to a level of radiological dose or risk associated with
that potential exposure. The concentration depends on both the mass
release rate of the radionuclides as well as the volumetric flux of
water along the different pathways in the different components.
We note that the NRC modified its definition of groundwater in its
final rule to be consistent with the EPA's definition of groundwater.
This new definition limits groundwater to water that is in the
saturated zone, for purposes of demonstrating compliance with
radionuclide concentration limits in groundwater that is within the
representative volume of water, i.e., water that is located within the
accessible environment. DOE did not have a definition of groundwater in
its proposed rule and has decided not to add one now. DOE's historical
groundwater evaluations include a comprehensive evaluation of water
characteristics above the drift in the unsaturated zone, below the
drift in the unsaturated and the saturated zones, to the repository
site boundary and into the accessible environment beyond the controlled
area of the site. Hence, these evaluations include, as they should,
evaluation of groundwater in both unsaturated and saturated zones. DOE
does not believe a conforming definition is necessary for purposes of
estimating likely compliance with NRC's groundwater standard. In
estimating likely compliance with the NRC groundwater protection
standard, DOE will evaluate radionuclide concentration limits in
groundwater in the saturated zone (in the representative volume of
water), in accordance with NRC's rule.
Section 963.17(b) presents three final criteria (separately
enumerated from section 963.17(a)) under the category of disruptive
processes and events. These criteria relate to disruptive processes and
events that could potentially release radionuclides directly to the
human environment, or otherwise adversely affect the characteristics of
the system. The criteria pertinent to assessing repository performance
that fall in this category include: (1) Volcanism--for example, the
probability and potential consequences of a volcanic eruption
intersecting the repository; (2) seismic events--for example, the
probability and potential consequences of an earthquake on the
underground facilities or hydrologic system; and (3) nuclear
criticality--for example, the probability and potential consequences of
a self-sustaining nuclear reaction as a result of chemical or physical
processes affecting the waste either in or after release from breached
waste packages.
In proposed part 963, DOE included a fourth disruptive process and
event criterion of inadvertent human intrusion. This criterion was not
included in final 963 because the treatment of a possible human
intrusion event for the postclosure period is dealt with through a
prescribed human intrusion standard, part 63.321, and a prescribed set
of assumptions for the human intrusion scenario, part 63.322. A
separate performance assessment analysis is required to assess the
impacts of the postulated human intrusion event to determine whether
the individual protection standard in the case of human intrusion is
applicable (i.e., if the human intrusion is determined by DOE to occur
at or before 10,000 years), or whether the information and analyses
relative to the exposures from the human intrusion event should be
included in the environmental impact statement for the Yucca Mountain
site as an indication of long-term performance. To make consistent the
NRC requirements for human intrusion analyses and the structure of
performance analyses required under part 963, DOE believes it
preferable not to retain an inadvertent human intrusion event as a
separate criterion. This change does not change the substance or
requirements for the human intrusion analysis, and therefore DOE views
this as a clarification of its rule.
VII. Regulatory Review
A. Review for Compliance With the National Environmental Policy Act
(NEPA)
One commenter questioned whether or not this rulemaking would
require compliance with NEPA. The issuance of these amendments to the
Guidelines is a preliminary decision-making activity pursuant to
subsections 112 (d) and 113(d) of the Act and therefore does not
require the preparation of an environmental impact statement pursuant
to subsection 102(2)(C) of the NEPA or any other environmental review
under subsection 102(2)(E) or (F) of the NEPA.
B. Review Under the Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) was enacted
by Congress to ensure that a substantial number of small entities do
not unnecessarily face significant negative economic impact as a result
of Government regulations. The DOE certifies that the rule amending the
Guidelines will not have a significant impact on a substantial number
of small entities. The final rule will not regulate or otherwise
economically burden anyone outside of the DOE. It merely articulates
considerations for the Secretary of Energy to use in determining
whether or not the Yucca Mountain site is suitable for development as a
repository. Moreover, in response to the revised notice of proposed
rulemaking, a few entities who commented were small entities, and none
of them identified economic burdens that the regulations would impose.
Accordingly, no regulatory flexibility analysis is required under the
Regulatory Flexibility Act.
C. Review Under the Paperwork Reduction Act
The DOE has determined that this final rule contains no new or
amended record keeping, reporting, or application requirements, or any
other type of information collection requirements subject to the
Paperwork Reduction Act (Pub. L. No. 96-511).
D. Review Under Unfunded Mandates Reform Act
The Unfunded Mandates Reform Act of 1995 (Pub. L. No. 104-4)
generally requires Federal agencies to closely examine the impacts of
regulatory actions on State, local, and tribal governments. Subsection
101(5) of Title I of that law defines a Federal intergovernmental
mandate to include any regulation that would impose an enforceable duty
upon State, local, or tribal governments, except, among other things, a
condition of Federal assistance or a duty arising from participating in
a voluntary federal program. Title II of that law requires each Federal
agency to assess the effects of Federal regulatory actions on State,
local, and tribal governments, in the aggregate, or to the private
sector, other than to the extent such actions merely incorporate
requirements specifically set forth in a statute. Section 202 of that
title requires
[[Page 57333]]
a Federal agency to perform a detailed assessment of the anticipated
costs and benefits of any rule that includes a Federal mandate which
may result in costs to State, local, or tribal governments, or to the
private sector, of $100 million or more. Section 204 of that title
requires each agency that proposes a rule containing a significant
Federal intergovernmental mandate to develop an effective process for
obtaining meaningful and timely input from elected officers of State,
local, and tribal governments.
This final rule is not likely to result in any Federal mandate that
may result in the expenditure by State, local, and tribal governments
in the aggregate, or by the private sector, of $100 million or more in
any one year. Further, the Guidelines in 10 CFR part 960, the final
amendments to part 960 and the final part 963 largely incorporate
requirements specifically provided in sections 112 and 113 of the Act.
Moreover, sections 112, 113 and 114 of the Act provide for meaningful
and timely input from elected officials of State, local and tribal
governments. Accordingly, no assessment or analysis is required under
the Unfunded Mandates Reform Act of 1995.
E. Review Under the Treasury and General Government Appropriations Act,
1999
Section 654 of the Treasury and General Government Appropriations
Act, 1999 (Public Law 105-277) requires Federal agencies to issue a
Family Policymaking Assessment for any final rule or policy that may
affect family well-being. Today's final rulemaking would not have any
impact on the autonomy or integrity of the family as an institution.
Accordingly, DOE has concluded that it is not necessary to prepare a
Family Policymaking Assessment.
F. Review Under Executive Order 12866
Section 1 of Executive Order 12866 (``Regulatory Planning and
Review''), 58 FR 51735, establishes a philosophy and principles for
Federal agencies to follow in promulgating regulations. Section 1(b)(9)
of that Order provides: ``Wherever feasible, agencies shall seek views
of appropriate State, local, and tribal officials before imposing
regulatory requirements that might significantly or uniquely affect
those governmental entities. Each agency shall assess the effects of
Federal regulations on State, local, and tribal governments, including
specifically the availability of resources to carry out those mandates,
and seek to minimize those burdens that uniquely or significantly
affect such governmental entities, consistent with achieving regulatory
objectives. In addition, agencies shall seek to harmonize Federal
regulatory actions with regulated State, local and tribal regulatory
and other governmental functions.''
Section 6 of Executive Order 12866 provides for a review by the
Office of Information and Regulatory Affairs (OIRA) of a ``significant
regulatory action,'' which is defined to include an action that may
have an effect on the economy of $100 million or more, or adversely
affect, in a material way, the economy, competition, jobs,
productivity, the environment, public health or safety, or State,
local, or tribal governments. The Department has concluded that this
final rule is a significant regulatory action that requires a review by
the OIRA. DOE submitted this rule for OIRA clearance, and OIRA has
completed its review.
One commenter suggested that, under Executive Order 12866, DOE
should assess the effects of this rulemaking on State, local, and
tribal governments including reasonable efforts to minimize any burdens
that uniquely or significantly affect such governmental entities. The
commenter argued that ongoing characterization and development of the
Yucca Mountain site affected the economy, jobs, the environment, and
public health and safety. While certain determinations in DOE's nuclear
waste repository program may have such effects that can be analyzed,
the decision to promulgate today's rule is not one of them. It will not
regulate anyone other than DOE officials. It will affect preliminary
decision-making in a way that does not have specific identifiable
economic, environmental, or health effects.
G. Review Under Executive Order 12875
Executive Order 12875 (Enhancing Intergovernmental Partnership),
provides for reduction or mitigation, to the extent allowed by law, of
the burden on State, local and tribal governments of unfunded Federal
mandates not required by statute. The analysis under the Unfunded
Mandates Reform Act of 1995, above, satisfies the requirements of
Executive Order 12875. Accordingly, no further analysis is required
under Executive Order 12875.
H. Review Under Executive Order 12898
Executive Order 12898 (Federal Actions to Address Environmental
Justice in Minority Populations and Low-Income Populations) requires
Federal agencies to achieve environmental justice by identifying and
addressing, as appropriate, disproportionately high and adverse human
health and environmental effects of its programs, policies, and
activities on minority and low-income populations. One commenter on the
proposed rule said that DOE should fully apply this Executive Order to
this rulemaking, but did not provide any supporting reasons. In DOE's
view, the requirements of Executive Order 12898 are not implicated by
this rulemaking. This rulemaking has direct effects or regulates only
DOE, and therefore will not have disproportionate and adverse human
health effects on minority and low-income populations.
I. Review Under Executive Order 12988
With respect to the review of existing regulations and the
promulgation of new regulations, section 3(a) of Executive Order 12988,
``Civil Justice Reform,'' 61 FR 4729 (February 7, 1996), imposes on
Executive agencies the general duty to adhere to the following
requirements: (1) Eliminate drafting errors and ambiguity; (2) write
regulations to minimize litigation; and (3) provide a clear legal
standard for affected conduct rather than a general standard and
promote simplification and burden reduction. With regard to the review
required by section 3(a), section 3(b) of Executive Order 12988
specifically requires that Executive agencies make every reasonable
effort to ensure that the regulation: (1) Clearly specifies the
preemptive effect, if any; (2) clearly specifies any effect on existing
Federal law or regulation; (3) provides a clear legal standard for
affected conduct while promoting simplification and burden reduction;
(4) specifies the retroactive effect, if any; (5) adequately defines
key terms; and (6) addresses other important issues affecting clarity
and general draftsmanship under any Guidelines issued by the Attorney
General. Section 3(c) of Executive Order 12988 requires Executive
agencies to review regulations in light of applicable standards in
section 3(a) and section 3(b) to determine whether they are met or it
is unreasonable to meet one or more of them. The DOE has completed the
required review and determined that, to the extent permitted by law,
the final rule meets the relevant standards of Executive Order 12988.
J. Review Under Executive Order 13084
Under Executive Order 13084, ``Consultation and Coordination with
Indian Tribal Governments,'' DOE may not issue a discretionary rule
that significantly or uniquely affects Indian tribal governments and
imposes substantial direct compliance costs.
[[Page 57334]]
This final rulemaking would not have such effects. Accordingly,
Executive Order 13084 does not apply to this rulemaking.
K. Review Under Executive Order 13132
Executive Order 13132 creates special requirements for preemption
and inter-governmental consultation with regard to rules that have
federalism implications. According to the Executive Order, a policy has
federalism implications if it has ``substantial direct effect on
States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government.''
One of the county governments in Nevada asserted that DOE should be
demonstrating consideration of the effects of the rule on State and
local governments, the relationship between the Federal government and
the States, or the distribution of power and responsibility among
various levels of government. The comment was conclusory and did not
identify any ``substantial direct'' effects that would warrant
consideration under the executive order. For a variety of reasons, DOE
is of the view that the special requirements of the Executive Order
13132 do not apply to this rule. First, the rule does not preempt State
law. Second, the rule applies directly only to DOE and deals with a
preliminary stage in a decision-making process about the Yucca Mountain
site that calls for additional inter-governmental consultation and
public hearings. Third, the rule does not regulate or alter the
relationship between the United States and State, local, and tribal
governments because the terms of that relationship are set forth in the
NWPA. Fourth, the rule has no impact on the distribution of power and
responsibilities among various levels of government.
L. Review Under Executive Order 13211
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355
(May 22, 2001) requires Federal agencies to prepare and submit to the
Office of Information and Regulatory Affairs (OIRA), Office of
Management and Budget, a Statement of Energy Effects for any proposed
significant energy action. A ``significant energy action'' is defined
as any action by an agency that promulgates or is expected to lead to
the promulgation of a final rule, and that: (1) Is a significant
regulatory action under Executive Order 12866, or any successor order;
and (2) is likely to have a significant adverse effect on the supply,
distribution, or use of energy; or (3) is designated by the
Administrator of OIRA, as a significant energy action. For any proposed
significant energy action, the agency must give a detailed statement of
any adverse effects on energy supply, distribution, or use should the
proposal be implemented, and of reasonable alternatives to the action
and their expected benefits to energy supply, distribution, and use.
Today's rule is not likely to have a significant adverse effect on
the supply, distribution, or use of energy, and has not been designated
by OIRA as a significant energy action. Accordingly, DOE has not
prepared a Statement of Energy Effects.
M. Congressional Notification
As required by 5 U.S.C. 801, DOE will submit to Congress a report
regarding the issuance of today's final rule prior to the effective
date set forth at the outset of this notice of final rulemaking. The
report will state that it has been determined that the rule is not a
``major rule'' as defined by 5 U.S.C. 801(2).
List of Subjects in 10 CFR Parts 960 and 963
Criteria, Environmental protection, Geologic repositories, Nuclear
energy, Nuclear materials, Radiation protection, Suitability, Waste
disposal.
Issued in Washington, DC, on November 8, 2001.
Lake H. Barrett,
Acting Director, Office of Civilian Radioactive Waste Management.
For the reasons stated in the preamble, DOE hereby amends part 960,
and adds a new part 963 to Chapter II of Title 10 of the Code of
Federal Regulations as follows:
PART 960--GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF
POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY
1. The authority citation for 10 CFR part 960 is revised to read as
follows:
Authority: 42 U.S.C. 2011 et seq., 42 U.S.C. 7101 et seq., 42
U.S.C. 10101 et seq.
2. The part heading for Part 960 is revised to read as set forth
above.
Sec. 960.1 [AMENDED]
3. Section 960.1 is amended by removing the phrase ``for the
development of repositories'' from the first sentence and removing the
phrase ``and any preliminary suitability determinations required by
Section 114(f)'' from the second sentence.
4. Section 960.2 is amended by revising the definitions of ``Act,''
``Application'' and ``Determination'' to read as follows:
Sec. 960.2 Definitions.
* * * * *
Act means the Nuclear Waste Policy Act of 1982, as amended.
* * * * *
Application means the act of making a finding of compliance or
noncompliance with the qualifying or disqualifying conditions specified
in the guidelines of subparts C and D of this part.
* * * * *
Determination means a decision by the Secretary that a site is
suitable for site characterization for the selection of a repository,
consistent with applications of the guidelines of subparts C and D of
this part in accordance with the provisions set forth in subpart B of
this part.
* * * * *
Subpart B--Implementation Guidelines
Sec. 960.3 [Amended]
5. Section 960.3 is amended by removing the phrase ``for the
development of repositories'' from the first sentence.
Sec. 960.3-1-4-4 [Removed]
6. Section 960.3-1-4-4 is removed.
7. Section 960.3-1-5 is revised to read as follows:
Sec. 960.3-1-5 Basis for site evaluations.
(a) Evaluations of individual sites and comparisons between and
among sites shall be based on the postclosure and preclosure guidelines
specified in subparts C and D of this part, respectively. Except for
screening for potentially acceptable sites as specified in Sec. 960.3-
2-1, such evaluations shall place primary significance on the
postclosure guidelines and secondary significance on the preclosure
guidelines, with each set of guidelines considered collectively for
such purposes. Both the postclosure and the preclosure guidelines
consist of a system guideline or guidelines and corresponding groups of
technical guidelines.
(b) The postclosure guidelines of subpart C of this part contain
eight technical guidelines in one group. The preclosure guidelines of
subpart D of this part contain eleven technical guidelines separated
into three groups that represent, in decreasing order of importance,
preclosure radiological safety; environment, socioeconomics, and
transportation; and ease and cost of siting, construction, operation,
and closure.
[[Page 57335]]
(c) The relative significance of any technical guideline to its
corresponding system guideline is site specific. Therefore, for each
technical guideline, an evaluation of compliance with the qualifying
condition shall be made in the context of the collection of system
elements and the evidence related to that guideline, considering on
balance the favorable conditions and the potentially adverse conditions
identified at a site. Similarly, for each system guideline, such
evaluation shall be made in the context of the group of technical
guidelines and the evidence related to that system guideline.
(d) For purposes of recommending sites for development as
repositories, such evidence shall include analyses of expected
repository performance to assess the likelihood of demonstrating
compliance with 40 CFR part 191 and 10 CFR part 60, in accordance with
Sec. 960.4-1. A site shall be disqualified at any time during the
siting process if the evidence supports a finding by the DOE that a
disqualifying condition exists or the qualifying condition of any
system or technical guideline cannot be met.
(e) Comparisons between and among sites shall be based on the
system guidelines, to the extent practicable and in accordance with the
levels of relative significance specified above for the postclosure and
the preclosure guidelines. Such comparisons are intended to allow
comparative evaluations of sites in terms of the capabilities of the
natural barriers for waste isolation and to identify innate
deficiencies that could jeopardize compliance with such requirements.
If the evidence for the sites is not adequate to substantiate such
comparisons, then the comparisons shall be based on the groups of
technical guidelines under the postclosure and the preclosure
guidelines, considering the levels of relative significance appropriate
to the postclosure and the preclosure guidelines and the order of
importance appropriate to the subordinate groups within the preclosure
guidelines. Comparative site evaluations shall place primary importance
on the natural barriers of the site. In such evaluations for the
postclosure guidelines of subpart C of this part, engineered barriers
shall be considered only to the extent necessary to obtain realistic
source terms for comparative site evaluations based on the sensitivity
of the natural barriers to such realistic engineered barriers. For a
better understanding of the potential effects of engineered barriers on
the overall performance of the repository system, these comparative
evaluations shall consider a range of levels in the performance of the
engineered barriers. That range of performance levels shall vary by at
least a factor of 10 above and below the engineered-barrier performance
requirements set forth in 10 CFR 60.113, and the range considered shall
be identical for all sites compared. The comparisons shall assume
equivalent engineered barrier performance for all sites compared and
shall be structured so that engineered barriers are not relied upon to
compensate for deficiencies in the geologic media. Furthermore,
engineered barriers shall not be used to compensate for an inadequate
site; mask the innate deficiencies of a site; disguise the strengths
and weaknesses of a site and the overall system; and mask differences
between sites when they are compared. Releases of different
radionuclides shall be combined by the methods specified in appendix A
of 40 CFR part 191.
(f) The comparisons specified in paragraph (e) of this section
shall consist of two comparative evaluations that predict radionuclide
releases for 100,000 years after repository closure and shall be
conducted as follows. First, the sites shall be compared by means of
evaluations that emphasize the performance of the natural barriers at
the site. Second, the sites shall be compared by means of evaluations
that emphasize the performance of the total repository system. These
second evaluations shall consider the expected performance of the
repository system; be based on the expected performance of waste
packages and waste forms, in compliance with the requirements of 10 CFR
60.113, and on the expected hydrological and geochemical conditions at
each site; and take credit for the expected performance of all other
engineered components of the repository system. The comparison of
isolation capability shall be one of the significant considerations in
the recommendation of sites for the development of repositories. The
first of the two comparative evaluations specified in the paragraph (e)
of this section shall take precedence unless the second comparative
evaluation would lead to substantially different recommendations. In
the latter case, the two comparative evaluations shall receive
comparable consideration. Sites with predicted isolation capabilities
that differ by less than a factor of 10, with similar uncertainties,
may be assumed to provide equivalent isolation.
8. In Sec. 960.3-2, the last sentence is revised to read as
follows:
Sec. 960.3-2 Siting process.
* * * The recommendation of sites as candidate sites for
characterization shall be accomplished in accordance with the
requirements specified in Sec. 960.3-2-3.
Sec. 960.3-2-4 [Removed]
9. Section 960.3-2-4 is removed.
Appendix III to Part 960--[Amended]
10. Appendix III to Part 960 is amended as follows:
a. In paragraph 1, introductory text, first sentence, revise the
phrase ``the principal'' to read ``certain''.
b. In paragraph 1, remove the definition for ``Repository site
selection''.
c. In paragraph 3, remove the definition for the numeral ``4'' and
paragraphs ``(a)'' and ``(b)'' which follow.
d. The table to Appendix III is revised to read as follows:
Findings Resulting From the Application of the Qualifying and Disqualifying Conditions of the Technical
Guidelines at Major Siting Decisions
----------------------------------------------------------------------------------------------------------------
Siting decision
-------------------------------
Section 960 Guideline Condition Potentially Nomination and
acceptable recommendation
----------------------------------------------------------------------------------------------------------------
4-1(a)............................ System............... Qualifying........... .............. 3
4-2-1(a).......................... Geohydrology......... ......do............. .............. 3
4-2-1(d).......................... ......do............. Disqualifying........ .............. 1
4-2-2(a).......................... Geochemistry......... Qualifying........... .............. 3
4-2-3(a).......................... Rock Characteristics. ......do............. .............. 3
4-2-4(a).......................... Climatic Changes..... ......do............. .............. 3
4-2-5(a).......................... Erosion.............. ......do............. .............. 3
[[Page 57336]]
4-2-5(d).......................... ......do............. Disqualifying........ 1 1
4-2-6(a).......................... Dissolution.......... Qualifying........... .............. 3
4-2-6(d).......................... ......do............. Disqualifying........ 1 1
4-2-7(a).......................... Tectonics............ Qualifying........... .............. 3
4-2-7(d).......................... ......do............. Disqualifying........ 1 1
4-2-8-1(a)........................ Natural Resources.... Qualifying........... .............. 3
4-2-8-1(d)(1)..................... ......do............. Disqualifying........ 1 1
4-2-8-1(d)(2)..................... ......do............. ......do............. .............. 1
4-2-8-2(a)........................ Site Ownership and Qualifying........... .............. 3
Control.
5-1(a)(1)......................... System............... ......do............. .............. 3
5-1(a)(2)......................... ......do............. ......do............. .............. 3
5-1(a)(3)......................... ......do............. ......do............. .............. 3
5-2-1(a).......................... Population Density ......do............. .............. 3
and Distribution.
5-2-1(d)(1)....................... ......do............. Disqualifying........ 1 1
5-2-1(d)(2)....................... ......do............. ......do............. 1 1
5-2-1(d)(3)....................... ......do............. ......do............. .............. 1
5-2-2(a).......................... Site Ownership and Qualifying........... .............. 3
Control.
5-2-3(a).......................... Meteorology.......... ......do............. .............. 3
5-2-4(a).......................... Offsite Installations ......do............. .............. 3
and Operations.
5-2-4(d).......................... ......do............. Disqualifying........ 1 1
5-2-5(a).......................... Environmental Quality Qualifying........... .............. 3
5-2-5(d)(1)....................... ......do............. Disqualifying........ .............. 1
5-2-5(d)(2)....................... ......do............. ......do............. 1 1
5-2-5(d)(3)....................... ......do............. ......do............. 1 1
5-2-6(a).......................... Socioeconomic Impacts Qualifying........... .............. 3
5-2-6(d).......................... ......do............. Disqualifying........ .............. 1
5-2-7(a).......................... Transportation....... Qualifying........... .............. 3
5-2-8(a).......................... Surface ......do............. .............. 3
Characteristics.
5-2-9(a).......................... Rock Characteristics. ......do............. .............. 3
5-2-9(d).......................... ......do............. Disqualifying........ .............. 1
5-2-10(a)......................... Hydrology............ Qualifying........... .............. 3
5-2-10(d)......................... ......do............. Disqualifying........ .............. 1
5-2-11(a)......................... Tectonics............ Qualifying........... .............. 3
5-2-11(d)......................... ......do............. Disqualifying........ 1 1
----------------------------------------------------------------------------------------------------------------
11. New part 963 is added to read as follows:
PART 963--YUCCA MOUNTAIN SITE SUITABILITY GUIDELINES
Subpart A--General Provisions
963.1 Purpose.
963.2 Definitions.
Subpart B--Site Suitability Determination, Methods and Criteria
963.10 Scope.
963.11 Suitability determination.
963.12 Preclosure suitability determination.
963.13 Preclosure suitability evaluation method.
963.14 Preclosure suitability criteria.
963.15 Postclosure suitability determination.
963.16 Postclosure suitability evaluation method.
963.17--Postclosure suitability criteria.
Authority: 42 U.S.C. 2011 et seq.; 42 U.S.C. 7101 et seq.; 42
U.S.C. 10101, et seq.
Subpart A--General Provisions
Sec. 963.1 Purpose.
(a) The purpose of this part is to establish DOE methods and
criteria for determining the suitability of the Yucca Mountain site for
the location of a geologic repository. DOE will use these methods and
criteria in analyzing the data from the site characterization
activities required under section 113 of the Nuclear Waste Policy Act.
(b) This part does not address other information that must be
considered and submitted to the President, and made available to the
public, by the Secretary under section 114 of the Nuclear Waste Policy
Act if the Yucca Mountain site is recommended for development as a
geologic repository.
Sec. 963.2 Definitions.
For purposes of this part:
Applicable radiation protection standard means (1) For the
preclosure period, the preclosure numerical radiation dose limits in 10
CFR 63.111(a) and (b) and 63.204; and
(2) For the postclosure period, the postclosure numerical radiation
dose limits in 10 CFR 63.311 and 63.321 and radionuclide concentration
limits in 10 CFR 63.331.
Barrier means any material, structure or feature that prevents or
substantially reduces the rate of movement of water or radionuclides
from the Yucca Mountain repository to the accessible environment, or
prevents the release or substantially reduces the release rate of
radionuclides from the waste. For example, a barrier may be a geologic
feature, an engineered structure, a canister, a waste form with
physical and chemical characteristics that significantly decrease the
mobility of radionuclides, or a material placed over and around the
waste, provided that the material substantially delays movement of
water or radionuclides.
Cladding is the metallic outer sheath of a fuel rod element; it is
generally made of a corrosion resistant zirconium alloy or stainless
steel, and is intended
[[Page 57337]]
to isolate the fuel from the external environment.
Closure means the final closing of the remaining open operational
areas of the underground facility and boreholes after termination of
waste emplacement, culminating in the sealing of shafts and ramps,
except those openings that may be designed for ventilation or
monitoring.
Colloid means any fine-grained material in suspension, or any such
material that can be easily suspended.
Criteria means the characterizing traits relevant to assessing the
performance of a geologic repository, as defined by this section, at
the Yucca Mountain site.
Design means a description of the engineered structures, systems,
components and equipment of a geologic repository at Yucca Mountain
that includes the engineered barrier system.
Design bases means that information that identifies the specific
functions to be performed by a structure, system, or component of a
facility and the specific values or ranges of values chosen for
controlling parameters as reference bounds for design. These values may
be constraints derived from generally accepted ``state-of-the-art''
practices for achieving functional goals or requirements derived from
analysis (based on calculation or experiments) of the effects of a
postulated event under which a structure, system, or component must
meet its functional goals. The values for controlling parameters for
external events include:
(1) Estimates of severe natural events to be used for deriving
design bases that will be based on consideration of historical data on
the associated parameters, physical data, or analysis of upper limits
of the physical processes involved; and
(2) Estimates of severe external human-induced events to be used
for deriving design bases, that will be based on analysis of human
activity in the region, taking into account the site characteristics
and the risks associated with the event.
DOE means the U.S. Department of Energy, or its duly authorized
representatives.
Engineered barrier system means the waste packages, including
engineered components and systems other than the waste package (e.g.,
drip shields), and the underground facility.
Event sequence means a series of actions and/or occurrences within
the natural and engineered components of a geologic repository
operations area that could potentially lead to exposure of individuals
to radiation. An event sequence includes one or more initiating events
and associated combinations of repository system component failures,
including those produced by the action or inaction of operating
personnel. Those event sequences that are expected to occur one or more
times before permanent closure of the geologic repository operations
area are referred to as Category 1 event sequences. Other event
sequences that have at least one chance in 10,000 of occurring before
permanent closure are referred to as Category 2 event sequences.
Geologic repository means a system that is intended to be used for,
or may be used for, the disposal of radioactive wastes in excavated
geologic media. A geologic repository includes the engineered barrier
system and the portion of the geologic setting that provides isolation
of the radioactive waste.
Geologic repository operations area means a high-level radioactive
waste facility that is part of a geologic repository, including both
surface and subsurface areas, where waste handling activities are
conducted.
Geologic setting means geologic, hydrologic, and geochemical system
of the region in which a geologic repository is or may be located.
High-level radioactive waste means
(1) The highly radioactive material resulting from the reprocessing
of spent nuclear fuel, including liquid waste produced directly in
reprocessing and any solid material derived from such liquid waste that
contains fission products in sufficient concentration; and
(2) Other highly radioactive material that the Commission,
consistent with existing law, determines by rule requires permanent
isolation.
Human intrusion means breaching of any portion of the Yucca
Mountain disposal system within the repository footprint by any human
activity.
Infiltration means the flow of a fluid into a solid substance
through pores or small openings; specifically, the movement of water
into soil and fractured or porous rock.
Initiating event means a natural or human induced event that causes
an event sequence.
Near-field means the region where the adjacent natural
geohydrologic system has been significantly impacted by the excavation
of the repository and the emplacement of the waste.
NRC means the U.S. Nuclear Regulatory Commission or its duly
authorized representatives.
Perched water means ground water of limited lateral extent
separated from an underlying body of ground water by an unsaturated
zone.
Preclosure means the period of time before and during closure of
the geologic repository.
Preclosure safety evaluation means a preliminary assessment of the
adequacy of repository support facilities to prevent or mitigate the
effects of postulated initiating events and event sequences and their
consequences (including fire, radiation, criticality, and chemical
hazards), and the site, structures, systems, components, equipment, and
operator actions that would be relied on for safety.
Postclosure means the period of time after the closure of the
geologic repository.
Radioactive waste or waste means high-level radioactive waste and
other radioactive materials, including spent nuclear fuel, that are
received for emplacement in the geologic repository.
Reasonably maximally exposed individual means the hypothetical
person meeting the criteria specified at 10 CFR 63.312.
Reference biosphere means the description of the environment,
inhabited by the reasonably maximally exposed individual. The reference
biosphere comprises the set of specific biotic and abiotic
characteristics of the environment, including, but not limited to,
climate, topography, soils, flora, fauna, and human activities.
Seepage means the inflow of ground water moving in fractures or
pore spaces of permeable rock to an open space in the rock such as an
excavated drift.
Sensitivity study means an analytic or numerical technique for
examining the effects on model outcomes, such as radionuclide releases,
of varying specified parameters, such as the infiltration rate due to
precipitation.
Site characterization means activities, whether in the laboratory
or in the field, undertaken to establish the geologic conditions and
the ranges of the parameters of a candidate site relevant to the
location of a repository, including borings, surface excavations,
excavations of exploratory shafts, limited subsurface lateral
excavations and borings, and in situ testing needed to evaluate the
suitability of a candidate site for the location of a repository, but
not including preliminary borings and geophysical testing needed to
assess whether site characterization should be undertaken.
Surface facilities means all permanent facilities within the
restricted area constructed in support of site characterization
activities and repository construction, operation, and closure
activities, including surface
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structures, utility lines, roads, railroads, and similar facilities,
but excluding the underground facility.
System performance means the complete behavior of a geologic
repository system at Yucca Mountain in response to the features,
events, and processes that may affect it.
Total system performance assessment means a probabilistic analysis
that is used to:
(1) Identify the features, events and processes (except human
intrusion) that might affect the Yucca Mountain disposal system and
their probabilities of occurring during 10,000 years after disposal;
(2) Examine the effects of those features, events, processes, and
sequences of events and processes (except human intrusion) on the
performance of the Yucca Mountain disposal system; and
(3) Estimate the dose incurred by the reasonably maximally exposed
individual, including associated uncertainties, as a result of releases
caused by all significant features, events, processes, and sequences of
events and processes, weighted by their probability of occurrence.
Underground facility means the underground structure, backfill
materials, if any, and openings that penetrate the underground
structure (e.g., ramps, shafts and boreholes, including their seals).
Waste form means the radioactive waste materials and any
encapsulating or stabilizing matrix.
Waste package means the waste form and any containers, shielding,
packing, and other absorbent materials immediately surrounding an
individual waste container.
Yucca Mountain disposal system means the combination of underground
engineered and natural barriers within the controlled area that
prevents or substantially reduces releases from the waste.
Yucca Mountain site means the candidate site in the State of Nevada
recommended by the Secretary to the President under section
112(b)(1)(B) of the Nuclear Waste Policy Act of 1982 (NWPA) (42 U.S.C.
1032(b)(1)(B)) on May 27, 1986.
Subpart B--Site Suitability Determination, Methods, and Criteria
Sec. 963.10 Scope.
(a) The scope of this subpart includes the following for both the
preclosure and postclosure periods:
(1) The bases for the suitability determination for the Yucca
Mountain site as a location for a geologic repository;
(2) The suitability evaluation methods for applying the site
suitability criteria to a geologic repository at the Yucca Mountain
site; and
(3) The site suitability criteria that DOE will apply in accordance
with section 113(b)(1)(A)(iv) of the NWPA.
(b) DOE will seek NRC concurrence on any future revisions to this
subpart.
Sec. 963.11 Suitability determination.
DOE will evaluate whether the Yucca Mountain site is suitable for
the location of a geologic repository on the basis of the preclosure
and postclosure determinations described in Secs. 963.12 and 963.15. If
DOE's evaluation of the Yucca Mountain site for the location of a
geologic repository under Secs. 963.12 and 963.15 shows that the
geologic repository is likely to meet the applicable radiation
protection standards for the preclosure and postclosure periods, then
DOE may determine that the site is a suitable location for the
development of such a repository.
Sec. 963.12 Preclosure suitability determination.
DOE will apply the method and criteria described in Secs. 963.13
and 963.14 to evaluate the suitability of the Yucca Mountain site for
the preclosure period. If DOE finds that the results of the preclosure
safety evaluation conducted under Sec. 963.13 show that the Yucca
Mountain site is likely to meet the applicable radiation protection
standard, DOE may determine the site suitable for the preclosure
period.
Sec. 963.13 Preclosure suitability evaluation method.
(a) DOE will evaluate preclosure suitability using a preclosure
safety evaluation method. DOE will evaluate the performance of the
geologic repository at the Yucca Mountain site using the method
described in paragraph (b) of this section and the criteria in
Sec. 963.14. DOE will consider the performance of the system in terms
of the criteria to evaluate whether the geologic repository is likely
to comply with the applicable radiation protection standard.
(b) The preclosure safety evaluation method, using preliminary
engineering specifications, will assess the adequacy of the repository
facilities to perform their intended functions and prevent or mitigate
the effects of postulated Category 1 and 2 event sequences. The
preclosure safety evaluation will consider:
(1) A preliminary description of the site characteristics, the
surface facilities and the underground operating facilities;
(2) A preliminary description of the design bases for the operating
facilities and a preliminary description of any associated limits on
operation;
(3) A preliminary description of potential hazards, event
sequences, and their consequences; and
(4) A preliminary description of the structures, systems,
components, equipment, and operator actions intended to mitigate or
prevent accidents.
Sec. 963.14 Preclosure suitability criteria.
DOE will evaluate preclosure suitability using the following
criteria:
(a) Ability to contain radioactive material and to limit releases
of radioactive materials;
(b) Ability to implement control and emergency systems to limit
exposure to radiation;
(c) Ability to maintain a system and components that perform their
intended safety functions; and
(d) Ability to preserve the option to retrieve wastes during the
preclosure period.
Sec. 963.15 Postclosure suitability determination.
DOE will apply the method and criteria described in Secs. 963.16
and 963.17 to evaluate the suitability of the Yucca Mountain site for
the postclosure period. If DOE finds that the results of the total
system performance assessments conducted under Sec. 963.16 show that
the Yucca Mountain site is likely to meet the applicable radiation
protection standard, DOE may determine the site suitable for the
postclosure period.
Sec. 963.16 Postclosure suitability evaluation method.
(a) DOE will evaluate postclosure suitability using the total
system performance assessment method. DOE will conduct a total system
performance assessment to evaluate the ability of the geologic
repository to meet the applicable radiation protection standard under
the following circumstances:
(1) DOE will conduct a total system performance assessment to
evaluate the ability of the Yucca Mountain disposal system to limit
radiological doses and radionuclide concentrations in the case where
there is no human intrusion into the repository. DOE will model the
performance of the Yucca Mountain disposal system using the method
described in paragraph (b) of this section and the criteria in
Sec. 963.17. DOE will consider the performance of the system in terms
of the criteria to evaluate whether the Yucca Mountain disposal system
is likely to comply with
[[Page 57339]]
the applicable radiation protection standard.
(2) DOE will conduct a separate total system performance assessment
to evaluate the ability of the Yucca Mountain disposal system to limit
radiological doses in the case where there is a human intrusion as
specified by 10 CFR 63.322. DOE will model the performance of the Yucca
Mountain disposal system using the method described in paragraph (b) of
this section and the criteria in Sec. 963.17. If required by applicable
NRC regulations regarding a human intrusion standard, Sec. 63.321, DOE
will consider the performance of the system in terms of the criteria to
evaluate whether the Yucca Mountain disposal system is likely to comply
with the applicable radiation protection standard.
(b) In conducting a total system performance assessment under this
section, DOE will:
(1) Include data related to the suitability criteria in
Sec. 963.17;
(2) Account for uncertainties and variabilities in parameter values
and provide the technical basis for parameter ranges, probability
distributions, and bounding values;
(3) Consider alternative models of features and processes that are
consistent with available data and current scientific understanding,
and evaluate the effects that alternative models would have on the
estimated performance of the Yucca Mountain disposal system ;
(4) Consider only events that have at least one chance in 10,000 of
occurring over 10,000 years;
(5) Provide the technical basis for either inclusion or exclusion
of specific features, events, and processes of the geologic setting,
including appropriate details as to magnitude and timing regarding any
exclusions that would significantly change the dose to the reasonably
maximally exposed individual;
(6) Provide the technical basis for either inclusion or exclusion
of degradation, deterioration, or alteration processes of engineered
barriers, including those processes that would adversely affect natural
barriers, (such as degradation of concrete liners affecting the pH of
ground water or precipitation of minerals due to heat changing
hydrologic processes), including appropriate details as to magnitude
and timing regarding any exclusions that would significantly change the
dose to the reasonably maximally exposed individual;
(7) Provide the technical basis for models used in the total system
performance assessment such as comparisons made with outputs of
detailed process-level models and/or empirical observations (for
example, laboratory testing, field investigations, and natural
analogs);
(8) Identify natural features of the geologic setting and design
features of the engineered barrier system important to isolating
radioactive waste;
(9) Describe the capability of the natural and engineered barriers
important to isolating radioactive waste, taking into account
uncertainties in characterizing and modeling such barriers;
(10) Provide the technical basis for the description of the
capability of the natural and engineered barriers important to
isolating radioactive waste;
(11) Use the reference biosphere and reasonably maximally exposed
individual assumptions specified in applicable NRC regulations; and
(12) Conduct appropriate sensitivity studies.
Sec. 963.17 Postclosure suitability criteria.
(a) DOE will evaluate the postclosure suitability of a geologic
repository at the Yucca Mountain site through suitability criteria that
reflect both the processes and the models used to simulate those
processes that are important to the total system performance of the
geologic repository. The applicable criteria are:
(1) Site characteristics, which include:
(i) Geologic properties of the site--for example, stratigraphy,
rock type and physical properties, and structural characteristics;
(ii) Hydrologic properties of the site--for example, porosity,
permeability,moisture content, saturation, and potentiometric
characteristics;
(iii) Geophysical properties of the site--for example, densities,
velocities and water contents, as measured or deduced from geophysical
logs; and
(iv) Geochemical properties of the site--for example,
precipitation, dissolution characteristics, and sorption properties of
mineral and rock surfaces.
(2) Unsaturated zone flow characteristics, which include:
(i) Climate--for example, precipitation and postulated future
climatic conditions;
(ii) Infiltration--for example, precipitation entering the mountain
in excess of water returned to the atmosphere by evaporation and plant
transpiration;
(iii) Unsaturated zone flux--for example, water movement through
the pore spaces, or flowing along fractures or through perched water
zones above the repository;
(iv) Seepage--for example, water dripping into the underground
repository openings from the surrounding rock.
(3) Near field environment characteristics, which include:
(i) Thermal hydrology--for example, effects of heat from the waste
on water flow through the site, and the temperature and humidity at the
engineered barriers.
(ii) Near field geochemical environment--for example, the chemical
reactions and products resulting from water contacting the waste and
the engineered barrier materials.
(4) Engineered barrier system degradation characteristics, which
include:
(i) Engineered barrier system component performance--for example,
drip shields, backfill, coatings, or chemical modifications, and
(ii) Waste package degradation--for example, the corrosion of the
waste package materials within the near-field environment.
(5) Waste form degradation characteristics, which include:
(i) Cladding degradation--for example, corrosion or break-down of
the cladding on the spent fuel pellets;
(ii) Waste form dissolution--for example, the ability of individual
radionuclides to dissolve in water penetrating breached waste packages.
(6) Engineered barrier system degradation, flow, and transport
characteristics, which include:
(i) Colloid formation and stability--for example, the formation of
colloidal particles and the ability of radionuclides to adhere to these
particles as they may migrate through the remaining barriers; and
(ii) Engineered barrier transport--for example, the movement of
radionuclides dissolved in water or adhering to colloidal particles to
be transported through the remaining engineered barriers and in the
underlying unsaturated zone.
(7) Unsaturated zone flow and transport characteristics, which
include:
(i) Unsaturated zone transport--for example, the movement of water
with dissolved radionuclides or colloidal particles through the
unsaturated zone underlying the repository, including retardation
mechanisms such as sorption on rock or mineral surfaces;
(ii) Thermal hydrology--for example, effects of heat from the waste
on water flow through the site.
(8) Saturated zone flow and transport characteristics, which
include:
(i) Saturated zone transport--for example, the movement of water
with dissolved radionuclides or colloidal particles through the
saturated zone
[[Page 57340]]
underlying and beyond the repository, including retardation mechanisms
such as sorption on rock or mineral surfaces; and
(ii) Dilution--for example, diffusion of radionuclides into pore
spaces, dispersion of radionuclides along flow paths, and mixing with
non-contaminated ground water.
(9) Biosphere characteristics, which include:
(i) Reference biosphere and reasonably maximally exposed
individual--for example, biosphere water pathways, location and
behavior of reasonably maximally exposed individual; and
(ii) Biosphere transport and uptake--for example, the consumption
of ground or surface waters through direct extraction or agriculture,
including mixing with non-contaminated waters and exposure to
contaminated agricultural products.
(b) DOE will evaluate the postclosure suitability of the Yucca
Mountain disposal system using criteria that consider disruptive
processes and events important to the total system performance of the
geologic repository. The applicable criteria related to disruptive
processes and events include:
(1) Volcanism--for example, the probability and potential
consequences of a volcanic eruption intersecting the repository;
(2) Seismic events--for example, the probability and potential
consequences of an earthquake on the underground facilities or
hydrologic system; and
(3) Nuclear criticality--for example, the probability and potential
consequences of a self-sustaining nuclear reaction as a result of
chemical or physical processes affecting the waste either in or after
release from breached waste packages.
[FR Doc. 01-28506 Filed 11-13-01; 8:45 am]
BILLING CODE 6450-01-P