Energy Department,

Federal Register: November 14, 2001 (Volume 66, Number 220)Rules and RegulationsPage 57297-57340From the Federal Register Online via GPO Access [wais.access.gpo.gov]

DOCID:fr14no01-17

[Page 57297]

Part V

Department of Energy

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

[Page 57298]

DEPARTMENT OF ENERGY

10 CFR Parts 960 and 963

Docket No. RW-RM-99-963RIN 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.

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

[Page 57300]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 cons