SECTION 1 – EXECUTIVE SUMMARY
The 24th semiannual progress report of the Yucca Mountain Site Characterization Project summarizes site characterization activities from October 1, 2000, through March 31, 2001. These activities are focused on evaluating the suitability of Yucca Mountain, Nevada, as a potential site for permanent geologic disposal of high-level radioactive wastes (HLW) and other nuclear materials, in accordance with the Nuclear Waste Policy Act of 1982 (NWPA), as amended2. This progress report documents the Project site characterization and other activities that contributed to completing the near-term programmatic and statutory objectives, which are:1.1 PROGRESS TOWARD NEAR-TERM OBJECTIVES
1.1.1 Site Recommendation
The NWPA requires the Secretary to make available to the public, and submit to the President, a comprehensive statement of the basis for his recommendation of the Yucca Mountain site, including the following documents:1.1.2 Environmental Impact Statement
The U.S. Department of Energy (DOE) is preparing a supplement to update the information in the Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada (see Section 6 and Appendix B). The supplement will evaluate the environmental impacts that could occur based on a flexible repository design that will function over the thermal operating range (see Section 4.2.1 and Appendix C in this document). The flexible repository design provides operational and control features that allow the repository to accommodate various heat loading scenarios by adjusting heat removal ventilation rates and duration to limit the maximum postclosure surface temperatures of the waste packages and the temperatures in the emplacement drift walls.1.1.3 Process Model Reports
Nine process model reports (PMRs) provide summary technical descriptions of models and submodels of the various total system performance assessment (TSPA) process models. These PMRs are synthesis reports that serve as primary references citing supporting analysis and model reports (AMRs), documents developed outside the Project, and other key documents (e.g., topical reports). These PMRs continue to be updated to incorporate new information, as it becomes available.1.1.4 Regulatory Framework
Interactions with the NRC continued to focus on addressing the NRC’s key technical issues (KTIs). By the end of the reporting period, nine technical exchange meetings had been held with the NRC on eight of the ten KTIs. Substantial progress has been made toward reaching an agreement on the work necessary to close each subissue and to obtain a "closed" or "closed-pending" status ("closed-pending" means that upon completion of the identified agreement items the subissues will be closed). For the eight KTIs discussed with the NRC through the end of this reporting period, only one subissue (Igneous Activity Consequences) has an "open" status, all the other subissues have a "closed" or "closed-pending" status. Two KTI meetings, one on the Igneous Activity subissue and one on the ninth KTI on Total System Performance Assessment and Integration, are scheduled for June and August 2001, respectively. The NRC’s tenth KTI is related to the Commission’s activities associated with development of the U.S. Environmental Protection Agency’s (EPA’s) Environmental Radiation Protection Standards for Yucca Mountain, Nevada (64 FR 46976 to be codified as 40 CFR 197), and does not involve interactions with the DOE.1.1.5 Repository Safety Strategy
The latest revision (REV 04 Interim Change Notice [ICN] 01) of the Repository Safety Strategy: Plan to Prepare the Safety Case to Support Yucca Mountain Site Recommendation and Licensing Considerations was issued in November 2000, but the strategy for moving forward to the LA is evolving. The repository safety strategy may be revised and separated into two parts:1.1.6 Nuclear Waste Technical Review Board
The Nuclear Waste Technical Review Board (NWTRB) issued a letter on September 20, 2000, to the Director of DOE’s Office of Civilian Radioactive Waste Management (OCRWM) recommending additional technical work to improve the existing technical basis for a possible SR decision. One of the NWTRB recommendations is the need for a "meaningful quantification of conservatisms and uncertainties in DOE’s performance assessments." An assessment was begun to improve the identification and communication of key uncertainties and to improve the transparency of the conservatisms that affect the calculated doses used to show compliance with the regulatory standard. An uncertainty and sensitivity analysis is being performed to develop an understanding of the overall effect of those uncertainties on repository performance. The NWTRB also recommended the need for:1.2 SITE CHARACTERIZATION
1.2.1 Geological Investigations
The Integrated Site Model provides a three-dimensional portrayal of site geologic features and includes the Geologic Framework Model, the Rock Properties Model, and the Mineralogic Model. Revisions of the Geologic Framework Model AMR and Rock Properties AMR were initiated during the reporting period. Natural analogs offer one of the multiple lines of evidence that provide a means, independent from TSPA, to build confidence in the ability of the Yucca Mountain site to isolate waste for thousands of years. A natural analog meeting was held on January 26, 2001, to present the results of ongoing natural analog studies and to elicit ideas for additional analog studies. Quantitative natural and anthropogenic analog studies continued in FY 2001 to provide confidence in the radionuclide transport and coupled process models. Increased emphasis was placed on analogs for coupled processes.1.2.2 Near-Field Environment
Near-field environment work concentrated on updating AMRs that support the Near-Field Environment PMR and documentation of thermal tests that validate conceptual models of coupled thermal-mechanical-hydrological-chemical processes. One field thermal test remained active during the reporting period. The Drift Scale Test, which is in its fourth year of heating, continued with collection of thermal-mechanical-hydrological-chemical response data. The thermal-hydrological processes observed in the test agreed with the conceptual model of heating a partially saturated rock mass. Both temperature and moisture content measured in the test agreed with model predictions. The Large Block Test showed that a well-defined dry-out zone was generated at the heater plane, as expected. The water in the block moved away from the heater plane, and water that moved downward from the heater zone drained away. Temperature measurements showed that condensate could reflux. The Large Block Test also showed that percolation of water that infiltrated from rainfall could penetrate the boiling zone, such that temperatures below the boiling zone were affected. Based on post-test analyses of core, the Large Block Test showed that heating had negligible effects on the mechanical and mineralogical properties of the rock matrix. Preliminary information from the Large Block Test indicated that thermal-hydrological processes observed in the test agreed with the conceptual model of heating a partially saturated rock mass.1.2.3 Site Unsaturated Zone Flow and Transport
Site unsaturated zone (UZ) flow and transport studies focused on improving the understanding of infiltration, flow and seepage, and further evaluation of chlorine-36 (36Cl) results that seem to indicate the possible existence of fast pathways for water to move from the surface and the repository horizon. Other investigations examined the origin of secondary calcite and silica deposits and fluid inclusions in secondary minerals as indicators of past groundwater movement. The Busted Butte UZ transport test continued to quantify the effects of hydrogeologic conditions that are expected at the proposed Yucca Mountain repository site. Preliminary UZ flow modeling of radionuclide transport data showed a close match between modeled results and data for a large-scale infiltration test. Modeling of tracer tests is ongoing. The Enhanced Characterization of the Repository Block (ECRB) "cross drift" testing focused on characterizing moisture movement and included seepage rate, relative humidity, and evaporation tests. The interpretation of results and planning of additional tests is continuing. Mineral precipitation is consistent with water vapor and carbon dioxide loss from films at very slow rates. Data collectively indicate that the mineral coatings were formed in a UZ setting that has been hydrologically stable over million-year time scales. After a two-year study, scientists at University of Nevada Las Vegas (UNLV) have concluded that hot water has not invaded the rocks of Yucca Mountain in 2 million years. The UNLV study has concluded that mineral precipitation at the site has been stable for at least the last 2 to 3 million years and is consistent with formation from low temperature, surficial fluids rather than saturation of the site by upwelling hydrothermal fluids.1.2.4 Site Saturated Zone Flow and Transport
Compilation of lithologic descriptions and stratigraphic correlations of the Phase II boreholes of the Nye County Early Warning Drilling Program (EWDP) was completed. Preparatory work was initiated for construction of new geologic cross sections along U.S. Highway 95 in support of revisions to the site-scale saturated zone (SZ) model. Samples were collected by UNLV from the Phase II EWDP wells for analysis of major anions, major cations, trace elements; and for the oxidation states of arsenic, selenium, and antimony. These analyses were completed and data are awaiting verification. The last three of four interval hydraulic tests, at the Alluvial Testing Complex, were conducted and drawdown measurements were made. Preliminary results indicate that there was very little diffusion of tracers into non-flowing porosity, but the tracers did drift during injection rest periods. Radionuclide batch sorption and column transport experiments in alluvium were initiated to complement experiments conducted in FY 2000. The interpretation of these tests is in progress and will be reported in the next reporting period. Saturated alluvium column experiments are studying the transport behavior of Plutonium-239 (239Pu) colloids. These tests will be completed and interpreted during the next reporting period. Water level monitoring activities continued with emphasis on closing out U.S. Geological Survey (USGS) efforts and transitioning the work to UNLV. Flow paths in the upper SZ downgradient from Yucca Mountain have been delineated using concentrations and relative proportions of major cations and anions in groundwater samples along with isotopic ratios. Groundwater beneath Yucca Mountain flows southeastward to the Fortymile Wash system where it mixes with recharge through alluvium in the wash. The chemical and isotopic data do not support discharge of the Yucca Mountain-Fortymile Wash system into Death Valley as previously suggested. Interpretation and refinement of SZ flow paths downgradient from Yucca Mountain are important because flow paths are a critical input to TSPA. Documentation of the Death Valley regional flow-system modeling study reports are expected to be submitted for technical review during the next reporting period.1.2.5 Disruptive Events
The Disruptive Events PMR and its supporting AMRs and calculations were updated to address a flexible approach to repository design and other issues.1.2.6 Seismic Hazards and Design
Several meetings with the NRC staff during the first half of FY 2001 addressed seismic issues related to effects on the engineered barrier system (EBS) and rockfall. Most work on the development of seismic design inputs has been suspended pending completion of geotechnical site investigations that will provide an enhanced set of site-specific inputs to the seismic design analyses. From June to December 2000, geotechnical field investigations and laboratory tests were focused on characterizing the potential site of the Waste Handling Building. Completion of a report documenting the results of the geotechnical investigations is planned for the first half of FY 2002.1.3 DESIGN AND CONSTRUCTION
During this reporting period, the project continued to develop repository design requirements, continued the waste form testing program, enhanced the materials testing program, continued to evolve the repository and waste package designs, and continued to construct sites for testing activities in the Exploratory Studies Facility (ESF). Advances in these areas are described in the following sections.1.3.1 Design Requirements
The Project continued to develop and revise the documents that establish the repository design requirements, and support the SR and the LA. These documents include:1.3.2 Repository
Evaluation continues for a flexible repository design that will function over a thermal operating range. The primary change is an expanded repository layout, relative to the layout for a warmer repository, which will support the flexible design concepts. Several ventilation and natural circulation tests have been completed and others are underway to validate ventilation system and other repository performance models. Tests are also underway to provide data on which minerals and salts in tuff can be dissolved and redeposited in the repository environment, and to confirm the thermal conductivity and specific heat of the host rock. The upgrade of the underground lighting system for the ESF is underway and projected to be complete during FY 2002. The upgrade of the underground portion of the communication system designs for the ESF Switchgear Building redesign and for the Busted Butte Mineback were completed.1.3.3 Waste Form Testing and Analysis/Modeling
During this reporting period, thirteen AMRs (see Section 4.3) and five calculations were issued. These AMRs significantly extended the range of calculated in-package chemistries and account for a wide range of potential waste forms. They also provide the documentation for the model abstractions to be used for cladding degradation, waste form degradation, waste form inventory, colloid concentrations, and solubility limits.1.3.4 Waste Package
The update of the Disposal Criticality Analysis Methodology Topical Report, Revision 01, was completed and submitted to the NRC for review. It addresses the open items identified in the NRC Safety Evaluation Report for Disposal Criticality Analysis Methodology Topical Report, Revision 0. The following reports and evaluations were completed during the reporting period:1.4 REPOSITORY PERFORMANCE
During this reporting period, the Project accomplished several advances in preclosure radiological safety assessment, postclosure performance assessment, and performance confirmation. These advances are described in the following sections.1.4.1 Preclosure Radiological Safety Assessment
The Preliminary Preclosure Safety Assessment for Monitored Geologic Repository Site Recommendation was revised to include the calculated dose to the lens of the eye. This safety assessment identifies facility hazards and their potential for initiating hazardous events, identifies Monitored Geologic Repository (MGR) design basis events (DBEs), evaluates DBE occurrence frequencies and consequences, and identifies those systems, structures, and components (SSCs) important to safety. This report also provides the MGR strategies for preclosure criticality safety, radiation protection, fire protection, and for the management of low-level radioactive waste. Six classification analyses were revised to document the quality assurance (QA) classification of the MGR SSCs. An analysis titled Plutonium/High-Level Vitrified Waste BDBE Dose Calculation was also issued during the reporting period. This analysis of a beyond DBE provides the dose consequence analysis for plutonium immobilized in vitrified HLW and showed that the unmitigated dose (i.e., no high-efficiency particulate air filtration) was below regulatory limits.1.4.2 Postclosure Performance Assessment
Performance Assessment–A significant milestone was achieved this reporting period in the area of postclosure performance assessment with the issuance of the Total System Performance Assessment (TSPA) Model for Site Recommendation document, which describes the integration of different aspects of the repository into one comprehensive model. The Total System Performance Assessment for the Site Recommendation (TSPA-SR) was also revised during this reporting period. This document provides a description of the TSPA-SR model, as well as the results for the model and multiple sensitivity analyses. This version of the TSPA-SR document incorporates updated climate for 1,000,000-year simulations and additional analyses of the effects of secondary phases on performance. Near Field Environment–Presentations were made to the NRC at the technical exchange meeting in January 2001, which addressed thermal-hydrological and coupled processes on seepage and near-field environment. Presentations were also made to the NRC at the technical exchange meeting in February 2001 (on the EBS), including thermal-hydrological-mechanical methodology, results, and validation. The Near Field Environment Process Model Report and two supporting AMRs were updated during this reporting period. EBS–Presentations were made to the NRC at the technical exchange meeting in January 2001 that addressed thermal effects on flow. Presentations were also made to the NRC at the technical exchange meeting in February 2001 that addressed repository design and thermal mechanical effects. Ten AMRs were updated during this period. Unsaturated Zone Flow and Transport–A presentation was made on UZ flow and transport to the NWTRB during the Winter 2001 Board Meeting on January 30 and 31, 2001. Six AMRs were updated during this period and the revision of the UZ Features, Events, and Processes AMR (Rev 01) is expected to be completed in mid-April. The USGS has revised the climate model and the infiltration model for the post-10,000-year climatic conditions during this reporting period. Saturated Zone Flow and Transport–The Saturated Zone Flow and Transport Process Model Report and five supporting AMRs were updated during this reporting period (see Section 5.2.5). The AMRs updated the models/analyses for hydrogeologic framework model for site-scale flow and transport; sub-gridblock scale dispersion in heterogeneous fracture media; geochemical and isotropic constraints on groundwater flow direction, mixing, and recharge; probability distribution for following interval spacing; and features, events, and processes in saturated zone flow and transport. Biosphere–Nine AMRs were updated during this reporting period. Analyses were provided to quantify some additional uncertainties inherent in the biosphere modeling. The biosphere model was presented with its sub-models, data, and findings to an International Biosphere Peer Review conducted under the auspices of the International Atomic Energy Agency (IAEA). The IAEA review resulted in 37 specific suggestions for further work on improving the basis of and extending the application of the modeling of the biosphere. The review will be followed with a response, and with a work plan to implement the suggestions that are appropriate for the Yucca Mountain Project. Disruptive Events–The Disruptive Events Process Model Report and four related AMRs were updated during this reporting period (see Section 5.2.7). The AMRs addressed the modeling for characterizing framework for igneous activity; dike propagation near drifts; igneous consequences modeling; and features, events, and processes. Waste Form–In this reporting period, the Project revised thirteen AMRs and one calculation. It also completed one new AMR, In-Package Chemistry for Waste Forms, and four new calculations. The new AMR significantly extends the range of calculated in-package chemistries, and accounts for a wide range of potential waste forms proposed for disposal in waste packages. Waste Package–The Waste Package Degradation Process Model Report and six supporting AMRs were updated during this reporting period (see Section 5.2.8). The Disposal Criticality Analysis Methodology Topical Report, Revision 01, was updated and sent to the NRC for review. The Waste Package Operations Fabrication Process Report and the Waste Package FY-00 Closure Methods Report were also issued. Other waste package reports and calculations issued during this reporting period are described in Sections 4.4.1 and 4.4.2. During this reporting period, a process for conducting peer review of waste package materials performance was initiated. Objectives for the peer review were developed and a chairman for the review panel was selected. The peer review is scheduled to begin in the third quarter of FY 2001.1.4.3 Performance Confirmation
The Performance Confirmation Plan and the Monitored Geologic Repository Test & Evaluation Plan are being updated during this reporting period to address KTI resolution agreements with the NRC, comments from the NWTRB, and the evolution of the MGR design.SECTION 2 – PROGRESS TOWARD NEAR-TERM OBJECTIVES
During this reporting period, Project activities continued to support major near-term objectives of preparing the final EIS and the documents necessary to enable the Secretary of Energy to determine whether Yucca Mountain will be recommended as the site of a geologic repository. Before the final EIS is issued, the technical analyses supporting the document will be updated, as appropriate, to reflect the ongoing progress of site studies and the response to public comments on the Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada, Volumes I and II ([105155]3 DOE 1999) and a supplement to the draft EIS (in progress, see Appendix B) . At the time of this reporting period, these activities are, or will be, integrated with Project work in site testing, design, performance assessment, and preparation of the SR decision materials. Work also continued during this reporting period on those technical activities necessary to support a possible SR. Before deciding whether to recommend to the President that the site be approved for development of a repository, the Secretary of Energy will consider the information presented in the SR decision materials, which includes the final EIS with comments received from the public, states, and Indian tribes; the NRC comments on sufficiency; and other information deemed appropriate. The NRC sufficiency comments are the Commission’s preliminary comments concerning the extent to which the at-depth site characterization analysis and the waste form proposal for the Yucca Mountain site seem to be sufficient for inclusion in any application to be submitted by the Secretary for licensing of the site as a repository (NWPA Section 114(a)(1)(E)). The SR and a comprehensive statement of the basis for the recommendation would be part of the documentation submitted to the President, as required by the NWPA Section 114(a)(1) [101681], supporting the Secretary’s decision. The latest revision of the repository safety strategy ([154951] CRWMS M&O 2001) was issued in November 2000. This revision reflects Project developments and information learned since previous revisions and includes a discussion of preclosure activities and strategies that were not addressed earlier. The revision is based on the work supporting SR decision materials and workshops conducted from February through June 2000. The various AMRs have been summarized in nine PMRs, which are synthesis reports that reference supporting analyses and modeling documentation, documents developed outside the Project, and other key documents (e.g., topical reports and other PMRs). The PMRs bring together the technical basis information for the various TSPA process models. The detailed technical information is contained in the supporting AMRs. Updating of PMRs continued throughout the reporting period. Each PMR addresses the following aspects related to a model:2.1 SITE RECOMMENDATION
The NWPA [101681] (42 U.S.C. 10134(a)(1)) requires the Secretary of Energy to determine the suitability of the Yucca Mountain site as a nuclear waste repository. To support the decision-making process, a suite of documents intended to provide sufficient information to allow the Secretary to make the required decision was defined. The documents that will be provided to the Secretary include:2.2 ENVIRONMENTAL IMPACT STATEMENT
The NWPA (Section 114(f)(1)) requires that a final EIS serve as one of the supporting elements for a decision on the SR and that the EIS accompany any Secretarial recommendation to the President. DOE will issue a supplement updating information in the Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada ([105155] DOE 1999). The supplement (in progress, see Section 6 and Appendix B) will evaluate environmental impacts that could occur based on the design and range of possible operating modes presented in the Yucca Mountain Science and Engineering Report (in progress, see Section 6 and Appendix B). The supplement will address only changes to the repository design and operating modes discussed in the draft EIS ([105155] DOE 1999). As described in the draft EIS ([105155] DOE 1999), the repository design has continued to evolve, reflecting evaluations of design options and ways in which to operate the repository (operating modes) that would reduce uncertainties and improve long-term performance and operational safety and efficiency. While aspects of the design have continued to evolve, the basic elements of the proposed action to construct, operate and monitor, and eventually close a geologic repository at Yucca Mountain, remain unchanged from the design discussed in the draft EIS. In the final EIS, DOE will consider the comments made during the public comment periods on the draft EIS ([105155] DOE 1999) and on the EIS supplement (in progress, see Appendix B).2.3 REGULATORY FRAMEWORK
The Energy Policy Act of 1992 [100017] directed a site-specific regulatory framework for evaluation of and decision-making about a repository at Yucca Mountain. Finalizing this regulatory framework is central to determining the suitability of the Yucca Mountain site for development as a repository in a manner that would protect public health and safety and protect the environment. The NRC proposed a regulation specific to the Yucca Mountain site (10 CFR Part 63 [101680] (64 FR 8640)) on February 22, 1999, and DOE submitted comments on the proposal on June 30, 1999. EPA proposed a regulation specific to the Yucca Mountain site (40 CFR Part 197 [105065] (64 FR 46976)) on August 27, 1999, and DOE submitted comments on the proposed regulation on November 26, 1999. The DOE comments emphasized that the technical aspects of the EPA rule should not only protect public health and safety and protect the environment, but conditions should also demonstrable in a rigorous licensing proceeding. DOE issued a revised proposal to amend its site suitability guidelines for Yucca Mountain on November 30, 1999 (10 CFR Part 963 [124754] (64 FR 67054)). The proposed regulations would appear as a new 10 CFR 963. DOE modified its 1996 proposal (10 CFR Part 960 [100211] [61 FR 66158]) to amend the guidelines in response to public comments and in light of Yucca Mountain site-specific regulations proposed by the NRC and EPA. DOE held two public hearings in Nevada on the proposed suitability guidelines (10 CFR Part 963): one on February 2, 2000, in Pahrump; and one on February 3, 2000, in Las Vegas. The public comment period opened on November 30, 1999, and ended March 20, 2000. DOE submitted a draft final rule for NRC concurrence on May 4, 2000. The final rules of DOE, NRC, and the EPA have not been issued as of the end of this reporting period. Although near-term work will continue to focus on activities necessary to enable the Secretary to make a decision regarding the suitability of the Yucca Mountain site as a repository, the DOE continues to interact with the NRC to ensure that Project activities are consistent with NRC expectations for submittal of a high-quality repository LA, should the Yucca Mountain site be recommended. On February 22, 1999, the NRC published its proposed licensing criteria specific to Yucca Mountain. The final rule has not been published as of end of this reporting period. The proposed regulations are risk-informed (focus licensing and regulatory attention on design and other issues, commensurate with their importance to public health and safety) and performance-based (rely on measurable outcomes). They also require use of multiple barriers to provide defense-in-depth against releases of radioactive materials and to enhance confidence that repository performance objectives will be met. Defense-in-depth means utilization of multiple natural and engineered barriers to ensure that system performance does not rely unduly on any single barrier while the NRC would leave in place its existing generic regulations for geologic repositories ([103540] 10 CFR 60), it would indicate that those regulations neither apply nor may be the subject of litigation in any NRC licensing proceedings for a repository at Yucca Mountain. The NRC has identified ten KTIs, topics that the NRC considers most important to evaluating performance of a repository at Yucca Mountain. DOE interactions with the NRC continue to focus on the KTIs and on the nine associated NRC issue resolution status reports that provide a framework for addressing the KTIs. DOE and the NRC conducted public meetings on KTIs including structural deformation and seismicity, criticality (a subissue contained in three KTIs), SZ flow, radionuclide transport, thermal effects on flow, evolution of the near-field environment, TSPA for SR, repository design and thermal mechanical effects, and data qualification. Each technical exchange meeting on the NRC KTIs has resulted in identifying those issues and subissues that can be considered "open" or "closed," or identifying the items of additional information that DOE must provide to the NRC and must be accepted by the NRC to close the "closed-pending" issues. For the KTI meetings held to date with the NRC, all of the associated KTI subissues have a "closed" or "closed-pending" status, except for one. Subissue 2 of the Igneous Activity KTI is considered "open." DOE is working with the NRC to identify any remaining actions necessary to achieve a "closed" or "closed-pending" status for this open subissue. DOE will continue to work to fulfill the agreements made at KTI technical exchanges by developing the documents identified in the agreements and providing them to the NRC for review. In addition, interactions will continue to be held to update the NRC on new information that relates to the KTIs. In addition to nine technical exchanges, quarterly QA and management meetings were conducted in December 2000. Interactions with the Advisory Committee on Nuclear Waste and the NWTRB continued to provide the status of Project activities and address issues raised by these two panels. The meetings provided multiple opportunities for DOE to explain the bases for Project positions and decisions and gain greater understanding of the concerns of these panels. The DOE is taking an active role in implementing the Licensing Support Network Rule ([103537] 10 CFR 2, Subpart J). The Licensing Support Network is a web-based system that makes documentary material available electronically to the public and to participants in any proceedings associated with an application for a license to receive and possess HLW at a geologic repository, if such an application is submitted. DOE comments regarding the NRC Proposed Rulemaking on 10 CFR 2, Subpart J; and DOE comments regarding the Licensing Support Network basic design standards, authority of the administrator, and timing of participant compliance certifications (which had been developed over the summer) were provided to the NRC on October 6, 2000. Work will continue to focus on overall Project implementation strategy and plans for development of the electronic system and procedures to ensure compliance with the final rule. The OCRWM Licensing Support Network Management & Operating Contractor Program Plan ([154682] CRWMS M&O 2000) was developed in support of this work. The program plan provides an overview of the OCRWM Licensing Support Network program and is integrated with the plan that describes the Information Technology activities associated with loading, validating, and testing the functionality of the OCRWM portion of the Licensing Support Network.2.4 REPOSITORY SAFETY STRATEGY
A key issue for the SR and NRC licensing decisions for a HLW repository at Yucca Mountain is the ability of the site to protect the public from any undue risk during operations and after permanent closure. The DOE is preparing preclosure and postclosure safety cases for the potential repository system. The latest revision of the repository safety strategy ([154951] CRWMS M&O 2001) was issued in November 2000. This revision provides a status of activities designed to support the defensibility and credibility of the safety cases. It also identifies a strategy for preparing an LA if the Yucca Mountain site is approved. Since November 2000, the set of activities has been replanned and the strategy for moving forward to the LA is changing. The repository safety strategy ([154951] CRWMS M&O 2001) will be revised and separated into two parts:2.4.1 Preclosure Safety Strategy
The elements of the repository safety case for the preclosure operational period are currently:2.4.2 Postclosure Safety Strategy
The latest revision of the repository safety strategy ([154951] CRWMS M&O 2001) addresses postclosure performance of the repository system, the principal factors of postclosure safety, the postclosure safety case for SR considerations, and the plans to complete the postclosure safety case for a potential LA. This revision is the basis for the postclosure safety case for the SR, although some replanning has occurred in response to the comments by the NWTRB ([152574] Cohon 2000). This replanning will evolve into a revised strategy for preparing a defensible and credible safety case for the LA. Consequently, the strategy discussed in the most recent repository safety strategy will change. The revised safety strategy, which will include preclosure and postclosure strategies, will be separated from a status discussion of the preclosure and postclosure safety cases. Postclosure Performance–In describing the status of the safety case, the repository safety strategy ([154951] CRWMS M&O 2001) emphasizes the attributes of the postclosure system that would determine its capability to isolate waste. Yucca Mountain provides physically and chemically stable rock well below the surface. Consequently, current analyses indicate that waste can be emplaced deep underground and isolated from the surface. In the underground environments, temperature, humidity, and chemistry change slowly. Current calculations indicate waste packages and drip shields maintain their integrity for tens of thousands of years. The waste packages alone are predicted to prevent any release of radionuclides for more than 10,000 years, at the time of this reporting period. The drip shield and drift invert provides additional barriers to limit release of radionuclides, even if the waste packages were to fail prematurely. However, a repository system at the Yucca Mountain site would provide more than stable environments for the engineered barriers. It would include multiple natural and engineered barriers that could provide safety margin and defense-in-depth. The site is arid; analyses indicate the combination of processes at the surface and the characteristics of the mountain limit the amount of seepage that can enter the emplacement drifts. Chemical conditions limit the concentrations of radionuclides in the water; analyses indicate that the combination of low seepage rates and these low concentrations constrains the amount of radionuclides that can be released from the engineered barriers, even if they are breached. The repository system also includes barriers to retard radionuclide migration away from the repository. The UZ at this site is sufficiently thick that waste can be emplaced more than 200 m below the surface and more than 100 m above the water table. In addition, the site is located approximately 20 km from inhabited areas. Most radionuclides are immobile in the rock at Yucca Mountain and cannot migrate through this rock to inhabited areas. Current analyses indicate that the combination of the limited ability of radionuclides to be mobilized in the EBS, and the delay of radionuclides that migrate to inhabited areas, limits the mean annual dose over the period of regulatory concern to levels not significantly greater than those from natural background radiation. Thus, the multiple natural and engineered barriers provide defense-in-depth; they combine to restrict mean annual dose well below either the NRC’s or the EPA’s proposed radiological exposure limit for greater than 10,000 years. Yucca Mountain is geologically stable and has changed little in the last several million years. Analyses have shown that disruptive events and processes that could affect long-term repository performance are extremely unlikely. The effect of igneous (volcanic) disruption has been included in the performance assessment using two separate models: one model for volcanic eruptions that intersect drifts and bring waste to the surface, and one model for underground igneous intrusions that damage waste packages and expose radionuclides for transport by groundwater. The probability of igneous disruption is extremely low (the mean annual probability is about one chance in 70 million per year). At the time of this report, the overall probability-weighted mean dose rate due to igneous disruption builds to a peak of approximately 0.08 mrem per year at 10,000 years (Yucca Mountain Science and Engineering Report [in progress see Appendix B]). Current Postclosure Safety Case–The postclosure safety case for the SR considerations continues to focus on the following elements:2.4.3 Nuclear Waste Technical Review Board
On September 20, 2000, the NWTRB issued a letter to the Director of DOE OCRWM ([152574] Cohon 2000) recommending additional technical work to improve the existing technical basis for a possible SR decision. One of the NWTRB recommendations is a "meaningful quantification of conservatisms and uncertainties in DOE’s performance assessments." The Project decided to address identified uncertainties by using a strategy that focused on treating uncertainties in a defensible, conservative manner. Sometimes conservative assumptions were made or parameter values were bounded. The design of the engineered barriers was enhanced to provide additional defense-in-depth, and natural analogs were investigated to provide additional information to support the performance model representations. The result is that the Project has used a mix of probabilistic representations and single-valued conservative estimates to characterize parameter uncertainties. There also are cases where more than one conceptual model may be consistent with available data and observations. In the absence of definitive data sets or compelling technical arguments for any specific conceptual, process, or abstraction model, a conservative representation was chosen. This approach has been used in other projects to demonstrate compliance with a regulatory standard, but it does not permit quantification of the degree of conservatism associated with the projected margin relative to the regulatory standard. In addition, the mixing of varying degrees of conservatism in models and parameter representations reduces the transparency of the analysis and makes difficult the development of coherent and consistent probability statements about projected repository performance. Accompanying the recognition of the inherent uncertainties and need for transparency is the responsibility to identify and communicate the uncertainties as clearly and meaningfully as possible. An assessment of the treatment of uncertainties was begun to improve this identification and communication. The key unquantified uncertainties were identified and are being quantified. An uncertainty and sensitivity analysis is being performed to develop an understanding of the implications to the overall effect on performance of those uncertainties. The following are the goals of ongoing efforts related to the treatment of uncertainty:SECTION 3 – SITE CHARACTERIZATION
This section summarizes progress on site characterization activities for the reporting period.3.1 GEOLOGIC INVESTIGATIONS
Geologic investigation work focused on updating model reports that support the Integrated Site Model, natural analog studies to improve confidence in conceptual models, and field investigations to support the design of the Waste Handling Building.3.1.1 Integrated Site Model
The Integrated Site Model provides a three-dimensional portrayal of site geologic features and includes the Geologic Framework Model, the Rock Properties Model, and the Mineralogic Model. Revisions of the Geologic Framework Model AMR ([138860] CRWMS M&O 2000) and Rock Properties Model (RPM3.1) Analysis Model Report ([113224] CRWMS M&O 1999) were initiated during the reporting period. The revisions are scheduled for completion in time to support downstream process models. The plan to qualify the mineralogical data ([154796] CRWMS M&O 2001) was completed, and at the end of the reporting period the qualification report was nearly complete. Once the report is finalized, changes in qualification status will be incorporated in a future update of the Mineralogical Model AMR ([138960] CRWMS M&O 2000). The NRC has acknowledged the Geologic Framework Model as an adequate tool for various site-scale analyses, and they intend to use the model to conduct independent analyses of various DOE models that incorporate the Geologic Framework Model ([135621] NRC 1999, p. 125).3.1.2 Natural Analogs
Natural analogs offer one of the multiple lines of evidence that support the understanding of conceptual models and provide a means, independent of TSPA, to build confidence in the ability of the Yucca Mountain site to isolate waste for thousands of years. A natural analog meeting was held on January 26, 2001, to provide a closer link between process modelers and the natural analog community. At the meeting, the results of ongoing natural analog studies were presented and ideas were elicited for potential additional analogs from four working groups (Flow and Transport in the Unsaturated and Saturated Zones, Waste Form/Waste Package/Engineered Barriers, Thermally Coupled Processes, and Disruptive Events). The results of these and subsequent discussions support arguments for multiple lines of evidence in every process-model related chapter of the FY01 Supplemental Science and Performance Analyses: Vol. 1 (in progress, see Appendix B). Some of the analog lines of evidence are being developed as part of the Natural Analog Synthesis Report due in FY 2002, which will include the results of ongoing quantitative natural analog studies. Quantitative natural and anthropogenic analog studies continued in FY 2001 to support confidence building in radionuclide transport and coupled process models. Increased emphasis was placed on analogs for coupled processes because of programmatic direction to explore a range of repository operating modes that would include a range of operating temperatures. Preliminary UZ flow modeling of radionuclide transport data from the Idaho National Environmental and Engineering Laboratory showed a close match between modeled results and data collected for a large-scale infiltration test. The model was able to account for perched water in the UZ at the interface between fractured basalt flows and sedimentary interbeds. Modeling of tracer tests is ongoing. Other continuing analogue studies included:3.1.3 Geologic Field Investigations
A collection of 13 abstracts of papers ([153982] USGS 2000) on geologic and geophysical characterization studies of Yucca Mountain was published. The summary papers describe results of studies to characterize the tectonic setting, fault behavior, and seismicity of the Yucca Mountain area and to provide essential data for assessment of possible risks posed by future seismic and fault activity. To support the Waste Handling Building design effort, compilation of geotechnical field data from trenches and boreholes at the ESF North Portal pad (Figure 3-1) continued. Development of geologic logs from geotechnical drilling and preparation of logs for technical review and checking continued. Final adjustments were made to the Sample Management Facility logs for the boreholes. Work on the interpretive report on geotechnical data from Waste Handling Building investigations progressed with development of an outline and compilation of reference citations for the geological interpretation chapter. The geotechnical field investigations of the Waste Handling Building site are described in Section 3.6.2.3.2 NEAR-FIELD ENVIRONMENT
Near-field environment work concentrated on updating AMRs that support the Near-Field Environment PMR and documentation of thermal tests that provide the data to be used in the validation process for the conceptual models of coupled thermal, mechanical, hydrological, and/or chemical processes.3.2.1 Near-Field Environment
The Near Field Environment Process Model Report update ([153363] CRWMS M&O 2000), was issued. Three supporting AMRs were updated to incorporate the no-backfill design as well as responses to technical and legal comments (see Section 5). Drafts of the near-field environment sections of the FY01 Supplemental Science and Performance Analyses: Vol. 1 (in progress, see Appendix B), are being developed to address the coupled effects of thermal-hydrological, thermal-hydrological-mechanical, and thermal-hydrological-chemical processes on seepage rates and on in-drift conditions. Information about effects on in-drift conditions and seepage rates is key to the development of process models that are abstracted into the TSPA model.3.2.2 Thermal Tests
Large-scale, field thermal tests are integral parts of the program to characterize Yucca Mountain. The thermal tests validate conceptual models of coupled thermal, mechanical, hydrological, and/or chemical processes that result from the heat produced by decaying radioactive waste. Only one field thermal test remained active during the reporting period. The Drift Scale Test, which is in its fourth year of heating, continued with collection of thermal, mechanical, hydrological, and chemical response data. As of March 31, 2001, problems have been identified with about 7.5 percent of the original test sensors and about 13 percent of the original borehole packers have failed. The number of problems in measurement devices is considered acceptable given the long-term nature and elevated temperatures of the Drift Scale Test. During November 2000, six rock samples were collected to investigate the mineralogic and petrologic response to the thermal-hydrological environment near the boiling zone. The DOE-NRC Technical Exchanges on Thermal Effects on Flow and Evolution of the Near Field Environment Key Technical Issues were conducted January 8-12, 2001, in Pleasanton, California. The associated NRC KTI subissue acceptance criteria were listed as "closed pending." One agreement reached during the NRC/DOE Technical Exchange on Thermal Effects on Flow involved the preparation of a white paper to address heat and mass loss through the bulkhead of the Drift Scale Test. The draft paper includes background discussion of prior related activities such as measurements, simulations, and analyses. The draft paper also discusses recent analyses that support assumptions, including the boundary condition for the bulkhead, used to simulate the thermal-hydrological response of the Drift Scale Test. A draft report on the Large Block Test analyses was prepared and will be submitted for review. Preliminary information from the Large Block Test indicated that, generally, the test performed as intended. The thermal-hydrological processes observed in the test agreed with the conceptual model of heating a partially saturated rock mass. Both temperature and moisture content measured in the test agreed with model predictions. The Large Block Test showed that a well-defined dry-out zone was generated at the heater plane, as expected. The water in the block moved away from the heater plane, and water that moved downward from the heater zone drained away. Temperature measurements showed that condensate could reflux, and the test also showed that percolating rainfall (similar to high percolation flux event) could penetrate the boiling zone, causing temperatures below the boiling zone to be affected. Post-test analyses of core samples from the Large Block Test showed that heating had negligible effect on the mechanical and mineralogical properties of the rock matrix. Fracture deformations were affected by heating, as was the moisture distribution in the block; the moisture distribution appeared to be related to the fracture heterogeneity. A heat pipe may have developed in the test, but additional analyses will be necessary to confirm the feature. Finally, observations indicate that microbes survived in the thermal environment and migrated from heater holes toward observation holes during the test. The microbe migration could have been assisted by drainage of water.3.3 SITE UNSATURATED ZONE FLOW AND TRANSPORT
Site UZ flow and transport studies focused on improving the understanding of infiltration, flow and seepage, and on further investigation of 36Cl results that seem to indicate existence of fast pathways between the surface and the repository horizon. Other investigations examined the origin of secondary calcite and silica deposits and fluid inclusions in secondary minerals as indicators of past groundwater movement. The Busted Butte UZ transport test continued to quantify the effects of hydrogeologic conditions that are expected at the potential Yucca Mountain repository site.3.3.1 ESF Alcove and Niche Studies
Studies in ESF niches and alcoves focused on seepage rate studies to validate the seepage calibration model, develop empirical relationships between relative humidity and evaporation, validate the results of the 36Cl study, and describe the origin of calcite-silica deposits. Niche Seepage Study–Data from the series of seepage rate threshold tests, which were conducted at three niches along the ESF main drift, were compared and used for the development, calibration, and validation of the Seepage Calibration Model. Revision 1 of the AMR on Seepage Calibration Model and Seepage Testing Data ([153045] CRWMS M&O 2001) was issued. To address the uncertainties associated with evaporation, an evaporation pan containing water was set up inside Niche 4788 to monitor the evaporation rate. The relative humidity and temperature of the air inside the niche are also being monitored. Results are pending, but the data will be used to develop an empirical relation between relative humidity and evaporation rate. 36Cl Validation Study–Participants in the 36Cl validation study met in Las Vegas in January 2001 to discuss and exchange information on leaching experiments conducted on a reference sample. Data from sample agitation experiments were used to develop time-dependent release curves for total chlorine, and the results were similar. The data indicate that a large fraction of chlorine is released early in the active methods that involved agitation of the sample in the water. Additional 36Cl analyses of the leachates obtained in experiments will be conducted on a reference sample to determine the ratio of meteoric chloride to rock chloride released as a function of time. When those analyses are completed, a standard protocol will be established, and analyses of core samples from the validation drilling will be resumed. As part of the 36Cl validation study, measurements of low-levels of tritium in pore water distilled from rock-core samples from the ESF were interpreted to indicate the presence or absence of fast pathways from the surface to the potential repository horizon ([154827] Patterson 2000). Tritium analyses for eight samples from the Bow Ridge Fault Alcove (Alcove 2; Figure 3-1) and six samples from along the ESF North Ramp indicate that detectable post-weapons-testing tritium occurs only within the Tiva Canyon Tuff at shallow depths in the Bow Ridge fault. No tritium has yet been detected deeper in the UZ system or lower stratigraphically within the nonwelded units of the PTn or within the underlying Topopah Spring Tuff along the North Ramp. Tritium analyses for pore water from the Topopah Spring Tuff, within the Sundance fault and the Ghost Dance fault in the ESF main drift, indicate that only two samples (one from the Sundance fault and one from the Ghost Dance fault) contained at least 1 tritium unit (TU, defined as one 3H atom in 1018 hydrogen atoms). This indicates that although fast percolation of young water into the Topopah Spring Tuff does occur, fast percolation appears to be extremely isolated in the northern part of the ESF. Along the ESF South Ramp, where the PTn is offset by numerous faults, 14 of 22 samples contained tritium concentrations greater than 1 TU, and several samples had concentrations in excess of 10 TU. The increased number of samples with greater concentrations of tritium indicates that fast percolation through the PTn and into the Topopah Spring Tuff is far more common in the southern part of the ESF. These results from tritium analyses generally are contrary to results for 36Cl analyses documented in the Analysis of Geochemical Data for the Unsaturated Zone, which indicated that fast pathways are more prevalent in the northern part of the ESF than in the southern part ([144986] CRWMS M&O 2000, pp. 66-67). The uranium-disequilibrium analysis conducted for the 36Cl validation study by AECL [Atomic Energy of Canada, Ltd] indicates that, on the basis of the lack of observed disequilibrium between uranium species (for samples taken from the Sundance and Drill Hole Wash fault zones), there is no evidence that these faults are preferred pathways for groundwater flowing through the Topopah Spring Tuff. By implication, rapid flow, within 50 years, from the surface to the level of the ESF is improbable. Based on a simple mass balance model, the results are consistent with an infiltration rate of about 1-mm per year (Gascoyne et al., in progress). Origin of Secondary Calcite and Silica Deposits–All available data on secondary calcite and silica deposits in the UZ have been re-evaluated to determine whether the water, from which the minerals were deposited, originated from the land surface or upwelled from deep in the subsurface. Geological, mineralogical, chemical, and isotopic evidence from coatings of calcite and silica on open fractures and lithophysal cavities within welded tuffs at Yucca Mountain, indicate an origin from meteoric water percolating through a thick (500 to 700 m) UZ rather than from pulses of upwelling groundwater ([154412] Paces et al. 2000). Geologic evidence of the nature of the UZ depositional environment includes the presence of coatings in only a small percentage of cavities, the restriction of coatings to fracture footwalls and cavity floors, and absence of mineral high-water marks indicative of water ponding. Systematic mineral sequences (early calcite, followed by chalcedony with minor quartz and fluorite, and finally calcite with intercalated opal forming the bulk of the coatings) indicate progressive changes in UZ conditions through time, rather than repeated saturation by flooding. Micrometer-scale growth banding in both calcite and opal reflects slow average growth rates over millions of years rather than a few growth episodes featuring rapid deposition. Isotopic compositions of carbon, oxygen, strontium, and uranium from calcite and opal indicate a percolation-modified meteoric water source, and collectively refute a deeper groundwater source. Chemical and isotopic variations in coatings also indicate long-term evolution of water compositions. Although some compositional changes are related to shifts in climate, growth rates in the deeper UZ are buffered from large changes in meteoric input. Isotopic and geologic evidence indicates that coatings of calcite and silica most likely formed from films of water flowing down connected fracture pathways. Mineral precipitation is consistent with water vapor and carbon dioxide loss from films at very slow rates. Data collectively indicate that the mineral coatings were formed in a UZ setting that has been hydrologically stable over million-year time scales ([154412] Paces et al. 2000). Fluid Inclusions in Secondary Mineral Deposits–Fluid inclusions are small voids in minerals that contain remnants of material from which the minerals crystallized. The remnants can be solids, liquids, or gases or any combination of these phases. Project scientists determined that calcite deposition in fractures and voids in the UZ likely began during cooling of the tuffs and continued to the present ([154414] Whelan et al. 2000). The paragenetic sequence of calcite and silica deposition in the UZ is: early-stage calcite followed by chalcedony and quartz, then calcite, locally with opal, during middle and late stages. Four types of fluid inclusions have been found in calcite assemblages: all liquid, all vapor, two-phase with large and variable vapor/liquid ratios, and a few two-phase inclusions with small and consistent vapor/liquid ratios. Inclusions of the fourth type are restricted to the early and possible middle calcite stages that developed during cooling of the tuffs or when regional magmatism was a possible heat source. In early calcite, the temperature of the fluid inclusions ranges from ~ 104° to ~ 185°F (~ 40° to ~ 85°C). Sub-boiling temperatures are compatible with deposition in the UZ and are supported by oxygen isotope data in early calcite. If the second and third types of fluid inclusions record heterogeneous trapping in the UZ, the observed fluid inclusions are inconsistent with water saturated conditions. Thus, at present, there is no evidence of upwelling water as a source for calcite and silica deposits nor do fluid inclusions in late calcite indicate elevated depositional temperatures. In closely related work, Project scientists analyzed strontium and oxygen isotopic data from surface-based boreholes to deduce the thermal history associated with the formation of fluid inclusions in calcite at greater than ambient temperatures ([154415] Marshall and Whelan 2000). These analyses indicate a gradual cooling of the tuffs over millions of years, in agreement with thermal modeling of magma beneath the 12-million year old Timber Mountain caldera just north of Yucca Mountain. This model predicts that temperatures significantly exceeding current geothermal values occurred prior to 6 million years ago. Furthermore, there is no evidence of Quaternary or recent thermal perturbations to the cooling of the tuffs. After a two-year study, scientists at UNLV have concluded that hot water has not invaded the rocks of Yucca Mountain in 2 million years ([155426] Wilson and Cline 2001). In the study, fluid inclusions in minerals in roughly half of the 155 rock samples collected throughout Yucca Mountain were formed at temperatures ranging from 113° to 141°F (45° to 60°C) more than 2 million years ago. These temperatures are well below the boiling point of water, 212°F (100°C); temperatures below the boiling point indicate that calcite in fractures and voids was not the result of deposition from the upwelling of geothermal water. Extensive petrography, paragenetic studies, and micro-probe mapping indicated that the early secondary minerals were heterogeneously distributed across the site and consist of variable amounts of calcite, opal, chalcedony, fluorite, and quartz ([154416] Wilson et al. 2001). Two-phase (gas and liquid) fluid inclusions with formation temperatures of 95° to 178°F (35° to 81°C) were identified in 50 percent of the samples in paragenetically early to earliest intermediate calcite, fluorite, and quartz. Two-phase fluid inclusions in calcite across the majority of the site trapped fluids between 113° and 141°F (45° to 60°C). Uranium-lead dating indicates that the two-phase fluid inclusions are older than a minimum age of 1.9 million years. More precise age constraints on the two-phase fluid inclusions (based on associated dateable material) indicated that the two-phase fluid inclusions were older than 4.0 to 5.3 million years. The UNLV study concluded that mineral precipitation at the site has been stable for at least the last 2 to 3 million years and is consistent with formation from low temperature, surficial fluids rather than saturation of the site by upwelling hydrothermal fluids.3.3.2 Enhanced Characterization of the Repository Block
The ECRB is more commonly referred to as the cross drift. Testing in the cross drift during the reporting period focused on characterizing moisture movement and included seepage rate tests and relative humidity and evaporation testing. Cross Drift Niche 1620 Test–Similar to middle nonlithophysal niches in the ESF main drift, the cross drift Niche 1620 test was designed to measure seepage and seepage thresholds in the lower nonlithophysal tuff unit, which has abundant cavities and, likely, high capillary strength. Seepage test #1 was started on February 21, 2001, and ended on April 1, 2001. During the test, approximately 300 liters of water were introduced into a borehole located above the niche within 1.5 to 2 m of the ceiling. The wetting front did not arrive at the niche ceiling, nor did water seep into the excavation during the test. The interpretation of results and planning of additional tests continued. Systematic Hydrological Characterization–Analysis of seepage data collected in borehole ECRB-SYBT-LA#2 during May and June of 2000 indicated that not all water that seeped into the drift was recorded by the data acquisition system due to evaporation losses. To resolve this uncertainty, measurements were made of relative humidity and water evaporation rate from an open pan in the tunnel space between the drift crown and the seepage collection curtain enclosure. Seepage tests in the same borehole (ECRB-SYBT-LA#2) were repeated in October 2000 with the evaporative rate corrections. Preliminary data from the modified testing system indicate that perhaps 10 to 20 percent of seepage water could have been lost due to evaporation in the evenings and weekends when the active ventilation was not in operation. Liquid-release tests in ECRB-SYBT-LA#1 were interrupted in January 2001 because of other field activities, but resumed in early March 2001 and are ongoing. Alcove 8/Niche 3 Test–In the infiltration experiment, designed to evaluate seepage from the ECRB Crossover Alcove (Alcove #8; Figure 3-1) into Niche 3, application of water to the small-plot test continued. Through December 14, 2000, when water applications to the small-plot test were terminated, no water had dripped into Niche 3. Planning continued for the large-plot, trench experiment, including development of permeameters that will replace the small-plot test. The trench experiment will provide data regarding flow characteristics of the fault in Alcove #8. Trench construction along the fault began on December 18, 2000, and was completed in January 2001. In preparation for the water application phase of the large-plot trench test, air-permeability testing was conducted in Alcove #8. Four permeameters were installed on the trench during February 2001, and water application began in early March 2001. Cross Drift Bulkhead and Moisture-Monitoring Studies–The cross drift bulkhead studies were initiated to evaluate flow and seepage processes in the rocks of the potential repository horizon and in the Solitario Canyon fault zone in support of UZ flow and seepage models. Data from the heat dissipation probes and the water content profiles indicated rewetting of rock behind the bulkheads after ventilation was turned off. Numerical model simulations, which assumed that the cross drift had returned to undisturbed moisture conditions, predicted a 50 percent chance that one or more seeps would occur behind the bulkheads. The most likely locations for seeps are in the western part of the cross drift, where the PTn is absent and surficial infiltration rates are highest. On January 22, 2001, the bulkheads were opened, ventilation was restored, and the cross drift was inspected and photographed for evidence of seepage. The walls were dry for the first 137 m (from the first bulkhead at 17+63 m to about 19+00 m). However, photographs from the initial entry showed condensation on the metallic surfaces of the vent line, utility lines, and conveyor belt. Most of the condensation evident in the initial photographs evaporated quickly but left behind patches of rust on metallic surfaces. The drip cloths between stations 24+75 m and 24+95 m were mottled blue (indicating that high pH moisture had contacted the cloth), had numerous drip marks, and showed an increase in the intensity of the mottling toward the second bulkhead. Moisture was most evident in the middle nonventilated zone between the second and third bulkheads where the cross drift intersects a major splay of the Solitario Canyon fault. All drip cloths hung in this zone were wet with some areas noticeably wetter. Ubiquitous moisture in the cross drift (indicated by rust spots, drip marks, and streaks) suggests that much of the moisture was from condensation rather than point-source seepage. Puddled water was observed in low spots on the drip cloths, where rock debris had fallen, and in low spots on the conveyer belt. Drier conditions were observed near the third bulkhead, and the nonventilated zone beyond the third bulkhead (26+00 m to 27+04 m) was dry. The moisture observed in the cross drift may have been condensation caused by warmer, moist air moving away from the tunnel boring machine heat source into cooler zones or possibly by cool air moving down the Solitario Canyon fault. Temperature and relative humidity data from the three nonventilated zones show that the temperature ranged between 77° and 90°F (25° and 32°C) and the relative humidity ranged from ~ 85 percent to near saturation. Although barometric pressure in the cross drift varied with time, the pressure appeared to be the same throughout the cross drift. An analysis is currently underway to compare fluctuations in cross drift temperature, relative humidity, and pneumatic pressure with variations in atmospheric pressure and variations in barometric pressure in the ventilated zone of the cross drift. Additional data collection and numerical modeling will be conducted during the next reporting period to determine whether any portion of the moisture observed in the cross drift was from seepage.3.3.3 Field-Scale Busted Butte UZ Transport Test Facility
The Busted Butte UZ transport test is an integrated field, laboratory, and modeling effort to quantify the effects of hydrogeologic conditions that are expected at the potential Yucca Mountain repository site. The test is designed to address solute and colloid movement through tuff layers that underlie the potential repository horizon. Busted Butte (Figure 3-2) was selected as the test location because the geologic layers that underlie the potential repository have been faulted up to the surface at Busted Butte. Thus, Busted Butte is a good analog site because it is a distal extension of both the vitric Calico Hills Formation and the Topopah Spring Tuff units as they exist beneath the potential repository horizon west of the Ghost Dance fault. Field Results–Phase 2, originally scheduled for injection termination on January 31, 2000, was extended through October 31, 2000. Nonreactive tracer breakthrough has occurred in 11 of 15 boreholes, and lithium (Li) breakthrough has occurred in 9 of 15 boreholes. Cores and rock samples from three new holes, as well as older cores, were used to identify and examine faults that crossed the test block and were intersected by the cores. The rock samples from the new cores were analyzed for both nonreactive and reactive metals as a means to understand the movement, or lack of movement, of metals through the test block. During January and February 2001, five overcores were taken around injection holes. The overcore locations were selected to examine near-injection transport at each of the injection rates. These samples were specifically intended to examine transport of metals. None of the metals (except Li) broke through at any of the collection holes. Analyses of the rock samples from the overcores are underway. Transport Computational Model–The transport computational model uses an unstructured grid that accurately represents the size and location of each borehole and injection point, unit boundaries, and faults. Simulations were run using parameters most representative of the Busted Butte transport test. Simulations used the computational code FEHM (finite element heat mass), which is being used for TSPA. Preliminary results show excellent qualitative agreement and strong quantitative agreement between model and analysis results. The modeling captures the breakthrough, overall shape of the tracer fronts in time, and the extent of mixing of tagged tracers. Simulations on grids incorporating greater amounts of site geology and stratigraphy have resulted in increasingly accurate results. Phase 1B tracer data and modeling incorporated explicit representation of fractures in the TSw and indicated that fractures do not play a significant role in flow and transport at the test location. Explicit representation in the model of the two faults in the Phase 2 block allowed testing of model sensitivity to variations in fault permeability. It is too early to make definite statements about the role of the faults in radionuclide transport, but information on the role of the faults will be obtained during the mineback of the Phase 2 block. Scaling/Travel Distance–Collection holes were placed at different distances from the injection holes to assess the influence of travel distance. Differing travel distances also provide a range of scales for studying transport, from tens of centimeters to meters. Preliminary results indicate that breakthrough times at the different distances scale approximately linearly with travel distance. Qualitative agreement is very good between model results and observational data, with the model representing borehole effects and layering, even though the actual injection rate appears to be 10 to 20 percent less than the planned rate. Preliminary results indicate the quantitative goodness of fit is reduced for the actual injection rate versus the designed rate simulations. The fact that the quality of fit uniformly decreases with change in injection rate suggests the possibility that scaling effects are significant. Heterogeneity–Tests in four boreholes, located along a line equidistant from the upper injection boreholes, indicate that differences in breakthrough pattern between these boreholes in the same rock unit are the result of heterogeneities in the test block. Analyses of collection pads from these boreholes demonstrate noticeable variability in both bromide breakthrough times and concentrations. A significant delay between breakthrough in borehole 12 versus boreholes 13 and 15 is possibly due to the presence of a fault or crack that runs through the back of the block. This fault appears to cut between the injection boreholes and borehole 12. Confirmation of the location of the fault is expected during the mineback of the Phase 2 block. AECL Radionuclide Transport Laboratory Experiments–A radionuclide migration experiment has been initiated at AECL’s Whiteshell Laboratories in a ~1 m3 block of tuff excavated from the Calico Hills Formation in the Busted Butte UZ Transport Test Facility. Injection of a mixture of conservative tracers (Na-fluorescein and 3H2O) and chemically reactive tracers (sodium-22 (22Na), cobalt-60 (60Co), technetium-99 (99Tc), cesium-137 (137Cs), and neptunium-237 (237Np)) was started in late March 2001. Within seven days, the Na-fluorescein had traveled between 10 and 20 cm through the tuff as determined from the chemical analysis of small aqueous samples taken along the flow path. No data are yet available for the radionuclides. The reduction-oxidation (redox) potential of the groundwater, extracted from the block, is being monitored. Initial data suggest that the environment in the block is becoming less oxidizing. This observation is supported by the presence of sulfate-reducing bacteria, as indicated by microbial analysis of the extracted water. The AECL Laboratory program to study radionuclide migration under unsaturated and saturated conditions is designed to provide experimental information on the transport behavior of radionuclides in nonwelded tuff. The results will be compared with the behavior observed for nonradioactive tracers during in situ experiments at the Busted Butte UZ Test Facility and those predicted based on laboratory sorption data. Spectrophotometric and radiometric analyses of pore water samples extracted from the unsaturated trial block have now been completed. Autoradiographs of the upper surface of the trial block indicate that the highest concentration of the radionuclide tracers is directly underneath the outlet of the delivery tube. This is consistent with the expectation that some of the tracers (60Co and 137Cs) would not migrate very far into the block but would be retained near the surface. Saturated block experiments have begun and results are expected during the next reporting period.3.3.4 Other Unsaturated Zone Field Investigations
Monitoring of in situ pneumatic pressure, temperature, and water potential continued in boreholes UE-25 UZ#4, UE-25 UZ#5, and USW NRG-7a. The data from UE-25 UZ#4 and UE-25 UZ#5 are presently being analyzed to provide infiltration estimates associated with the winter 1997-98 El Niño rainfall and runoff events. Boreholes UE-25 UZ#4 and UE-25 UZ#5 are located in Pagany Wash, about 1,100 feet northeast of the ESF North Ramp. The data from borehole USW NRG-7a are being collected and analyzed to ascertain any effects of ESF tests, such as those being conducted in the thermal alcove. Monitoring in these remaining surface-based UZ boreholes is scheduled to cease during the next reporting period. Opal and chalcedony in calcite and silica coatings of fractures and cavities, both above and below the modern water table, have been dated using uranium-lead series ([154828] Neymark et al. 2000). In the UZ, calcite and silica were deposited on the footwalls of some fractures and on the floors of lithophysal cavities; whereas, in the SZ, calcite and silica deposits typically fill fractures completely. Opal and chalcedony are common in UZ secondary mineral coatings but rare in the SZ. In the UZ, ages of secondary opal and chalcedony range from about 200,000 years to about 10 million years. Although only two samples have been analyzed, ages of secondary opal and chalcedony in the SZ (~11.2 and ~12.4 million years) are significantly older than the oldest ages determined for the UZ. Chemical, morphologic, and isotopic data indicate that the calcite and silica deposits within the modern UZ and SZ at Yucca Mountain formed from different processes and water sources. The uranium-lead age data also indicate that these deposits formed at different times. The processes of mineral deposition have been effective within the UZ throughout the past 10 million years; whereas, below the water table, they may have terminated in the mid-to-late Miocene epoch (5 to 23 million years ago).3.4 SITE SATURATED ZONE FLOW AND TRANSPORT
SZ work included compilation of borehole logs and geochemical analyses for major anions, major cations, trace elements, and the oxidation states of arsenic, selenium, and antimony for samples from the Nye County drill holes. At the Alluvial Testing Complex, hydraulic and tracer testing and radionuclide transport testing in alluvium continued. Locations of the Nye County holes and the Alluvial Testing Complex are shown in Figure 3-3.3.4.1 Nye County Early Warning Drilling Program
Compilation of lithologic descriptions and stratigraphic correlations, including interpretation of geophysical logs, for the Phase II Nye County EWDP boreholes was completed. Preparatory work, including the assembly of relevant surface geophysical and geologic data, was initiated for construction of new geologic cross sections along U.S. Highway 95 in support of revisions to the site-scale SZ model. Samples were collected by UNLV from the Phase II EWDP wells for the analysis of major anions, major cations, trace elements, and the oxidation states of arsenic, selenium, and antimony. These analyses were completed and data are awaiting verification. This information supports the Project efforts to conduct dissolved ion and isotope analyses including radiocarbon measurements of dissolved organic carbon to evaluate flow paths and travel times downgradient from the potential repository. The new data will be entered into the hydrochemistry database. Project scientists intend to develop a report describing the hydrochemistry database and how it can be used. Preliminary evaluation of geochemical data from different zones of five new EWDP wells suggests that the rare earth element concentrations in some of the samples are similar to those of the volcanic perched water in the Topopah Spring Tuff, while others are similar to water from a carbonate aquifer. Some patterns suggest a different facies than observed near Yucca Mountain or from the carbonate aquifer, but, overall, the patterns are unclear until additional new wells are drilled ([154829] Zhou et al. 2000).3.4.2 Alluvial Testing Complex: Hydraulic and Single Well Tracer Testing
At the Alluvial Testing Complex, the last three of the four interval hydraulic tests in borehole NC-EWDP-19D1 were conducted:3.4.3 Radionuclide Sorption and Transport Studies in the Alluvium
Radionuclide batch sorption and column transport experiments were initiated to complement experiments conducted in FY 2000. The studies focus on the radionuclides iodine-129 (129I), 99Tc, 237Np, and uranium (various isotopes). The tests feature the use of alluvium material and groundwater collected from NC-EWDP-19D and -19P. In contrast, last year’s studies did not include uranium and focused on using groundwater from EWDP-03S and alluvium material from EWDP-03S, -02D, and -09SX. Material and groundwater from NC-EWDP-19D and -19P are being used because these wells are considered to be in a primary SZ flow pathway from Yucca Mountain and the same materials are being used for the nonradioactive tracer sorption and column transport studies (see Section 3.4.1). The use of the same materials and water in the radionuclide and non-radionuclide tests will allow direct comparisons between the transport behavior of the radionuclides and nonradioactive surrogates. To date, batch measurements of 129I, 99Tc, and 237Np sorption onto crushed rock from several different alluvium intervals have been completed, and column transport tests (using the same material that is being used for Li column studies) have been conducted for each of these radionuclides. Column tests for 237Np have been conducted at three different flow rates to allow sorption kinetics and transport mechanisms to be deduced. The interpretation of all of these tests is in progress and will be reported in the next reporting period. Batch and column tests involving uranium-233 (233U) will be initiated as soon as this isotope is received. More laboratory studies are planned to obtain direct comparisons of the sorption and transport mechanisms of Li and 237Np, so that the conditions under which Li+ serves as a good surrogate for 237Np can be established. In addition to the radionuclide transport studies described above, saturated alluvium column experiments involving injections of 239Pu sorbed onto montmorillonite colloids (co-injected with tritiated water to serve as a nonsorbing solute for comparison) were initiated during the reporting period. Two columns were packed with the same alluvium material from NC-EWDP-19D that was used for the Li and radionuclide column transport studies (see above). However, one of the columns was packed after removing the smallest grain size fraction (by sieving) from the material so that the column would have a greater hydraulic conductivity and be representative of a more transmissive interval in the alluvium. The column effluents are being analyzed for tritium, 239Pu, and the montmorillonite colloids. The use of different alluvium size fractions in the two columns may allow colloid attachment and detachment rate constants to be estimated as a function of grain size from the colloid breakthrough curves. Preliminary results indicate that both the colloids and the 239Pu are being transported more efficiently through the column with the larger size fraction and the greater hydraulic conductivity. These tests will be completed and interpreted during the next reporting period.3.4.4 Other Saturated Zone Field Investigations
Water level monitoring activities continued with emphasis on closing out USGS efforts and transitioning the work to UNLV. Transition activities include preparations for demobilization of the water level monitoring equipment, review of UNLV technical plans, equipment calibration, and processing of quarterly data packages for FY 2000 and FY 2001. Preparation and review of the calendar year 1999 water-level data report continued. Flow paths in the upper SZ downgradient from Yucca Mountain have been delineated using concentrations and relative proportions of major cations and anions in groundwater samples along with isotopic ratios of hydrogen, oxygen, strontium, uranium, and carbon. The chemical data indicate that groundwater in the volcanic aquifers north of Yucca Mountain flows eastward toward the upper part of the Fortymile Wash flow system and westward into the Oasis Valley flow system ([155153] Peterman and Patterson 2000). Groundwater beneath Yucca Mountain flows southeastward to the Fortymile Wash system where it mixes with recharge through alluvium in the wash. (Groundwater sampled along Fortymile Wash is characterized by relatively large ratios of calcium plus magnesium to sodium plus potassium and oxygen-18 to oxygen-16 ratios similar to modern precipitation.) The chemical attributes of the mixed Fortymile Wash-Yucca Mountain groundwater remain essentially unchanged from Yucca Mountain south into the Amargosa Farms area indicating only minimal water/rock interaction along this flow path. Groundwater in the Oasis Valley system flows westward and merges with the Amargosa River flow system near Beatty. Water in the Amargosa River flow system mixes with higher sulfate water from Precambrian clastic rocks in the Funeral Mountains. Water from the Amargosa River flow system to the west and the Fortymile Wash flow system to the east do not mix until just north of Franklin Lake Playa, a major groundwater discharge area. The chemical and isotopic data do not support discharge of the Yucca Mountain-Fortymile Wash system into Death Valley as previously suggested. Interpretation and refinement of SZ flow paths downgradient from Yucca Mountain are important because flow paths are a critical input to TSPA. Numerous efforts in the Death Valley regional flow system modeling continued, with emphasis on software development, hydrogeologic framework model construction and refinement, and numerical groundwater flow modeling. Software to retrieve hydrogeologic data from various available databases for model input was modified, debugged, and installed, with emphasis on straightforward installation on diverse computer systems. Compilation of borehole lithologic information also continued and data were incorporated from the southwestern Nevada volcanic field database, the YMP geologic framework-model database, and the Nye County EWDP database. Hydrogeologic framework-model units and confidence rankings were assigned to all lithologic data. Borehole locations were coded and used to determine areas of duplicated data and areas of confidence. In parallel with these efforts, construction of the hydrogeologic framework model progressed with incorporation of recently developed geologic cross sections. Cross-section constructors relayed details of cross-section units to the modelers and a list of sections to be used in the new model was compiled. Staff began construction of cross-section templates to be used in processing of cross-section data for the transient model, including digitization of horizon information and merging of digitized information. In related work, a map titled Hydrostructural Map of the Death Valley Region (scale 1:350,000) was submitted for technical review. Preliminary regional groundwater-flow simulations were conducted throughout the reporting period and final parameter values and statistics were calculated. Several errors in the code used to calculate the statistical treatments were discovered and corrected. Evaluation of the final calibrated model also continued. Significant revisions to the sensitivity analysis package in the MODFLOW2000 ([155197] Harbaugh et al. 2000) modeling code pre-processor were completed, providing additional functionality for loading data files and simplifying manual data input. Development continued on modeling post-processors for the parameter estimation package. Documentation of the Death Valley regional flow system modeling study is progressing with work on preparation of two major draft reports. The first draft report, currently titled A Three-Dimensional Hydrogeologic Framework Model For Use With a Steady-State Numerical Ground-Water Flow Model of the Death Valley Regional Flow System, Nevada and California, describes the details of work on the hydrogeologic framework model. This report contains descriptions of the technical approaches used to calculate evapotranspiration and groundwater discharge and contains the hydrogeologic unit map used to produce the hydraulic properties report. Work on draft figures continues. The second report, currently titled A Three-Dimensional Numerical Model of Predevelopment Conditions in the Death Valley Regional Ground-Water Flow System, Nevada and California, describes work conducted in development of the steady-state groundwater flow model. The draft of this report is nearing completion; drafts of four out of the five chapters have been completed. Work continues on the draft of the chapter that describes model evaluation. Both reports are expected to be submitted for technical review during the next reporting period.3.5 DISRUPTIVE EVENTS
The Disruptive Events PMR ([151968] CRWMS M&O 2000) and a number of its supporting AMRs and calculations were updated to address a flexible approach to repository design and other issues. In addition to the potential design considered in earlier versions of the PMR and supporting documents, the current versions consider a case in which backfill is not used. In addition to changes related to a "no-backfill" design, the Characterize Framework for Igneous Activity at Yucca Mountain, Nevada ([151551] CRWMS M&O 2000) AMR reflects a change in the way the number of eruptive centers occurring within the potential repository footprint are calculated. The Number of Waste Packages Hit by Igneous Intrusion ([153097] CRWMS M&O 2000) calculation incorporated revised inputs on the number of dikes in a swarm and eruptive conduit diameter and used an areal calculation method instead of a linear approach. The Igneous Consequence Modeling for the TSPA-SR ([151560] CRWMS M&O 2000) AMR integrated the results of all the changes in supporting AMRs to describe inputs for the TSPA-SR document ([153246] CRWMS M&O 2000). These changes were also incorporated into the Features, Events, and Processes: Disruptive Events ([151553] CRWMS M&O 2000) AMR, which was updated to strengthen screening evaluations and to better document how secondary features, events, and processes were addressed. The Dike Propagation Near Drifts ([151552] CRWMS M&O 2000) AMR examined the generation of dikes in an environment featuring excavated drifts that remained open. Finally, the new Comparison of ASHPLUME Model Results to Representative Tephra Fall Deposits ([152998] CRWMS M&O 2000) calculation was completed to enhance confidence that the ASHPLUME software provides appropriate results.3.6 SEISMIC HAZARDS AND DESIGN
Several meetings with the NRC staff during the first half of FY 2001 focused on seismic issues related to seismic effects on the EBS, especially seismically induced rockfall. The discussions at these meetings helped to clarify the mutual understanding of the original Structural Deformation and Seismicity KTI agreement items.3.6.1 Seismic Design Inputs
Most work on the development of seismic design inputs was suspended pending completion of geotechnical site investigations that will provide an enhanced set of site-specific data to use as inputs to the analysis. Geotechnical site investigations and laboratory testing focused on characterizing the potential site of the Waste Handling Building to support development of seismic design ground motions and foundation design parameters. Preliminary results of the geotechnical investigations were reviewed and software qualification efforts were initiated.3.6.2 Geotechnical Site Investigations
From June to December 2000, a series of geotechnical field investigations and laboratory tests were performed to characterize the potential site of the Waste Handling Building for the purpose of developing seismic design ground motions and foundation design parameters. A limited program was also carried out at the crest of Yucca Mountain. One objective of these investigations was to characterize the seismic wave velocity structure beneath the Waste Handling Building and between the mountain crest and the emplacement area. In addition, the investigations were designed to characterize the dynamic and static material properties of the underlying geology. The dynamic parameters are required as input into the site response analysis for calculating the design ground motions at the emplacement area, at the Yucca Mountain crest, and at the Waste Handling Building. A particular focus of the Waste Handling Building studies was to quantify the variability in velocity structure across the site. The field program consisted of:SECTION 4 – DESIGN AND CONSTRUCTION
During this reporting period, the Project continued to develop repository design requirements, evolve the surface and subsurface repository design, evolve the waste package design, and construct sites for testing activities in the ESF. Advances in these areas are described in the following sections.4.1 DESIGN REQUIREMENTS
The Project continued to develop and revise the following documents that establish the repository design requirements and support the SR and the LA:4.2 REPOSITORY
4.2.1 Flexible Repository Design
Evaluation continued for a flexible repository design that will function over a thermal operating range. To support this design approach for the SR, an ICN was processed to the Site Recommendation Subsurface Layout ([154803] CRWMS M&O 2001). The primary change addressed by the ICN is to show an expanded repository layout that will support investigation into flexible design concepts. The most recent concepts for the overall ventilation system are described in Overall Subsurface Ventilation System ([146023] CRWMS M&O 2000) and Emplacement Ventilation System ([146103] CRWMS M&O 2000). These documents provide a basis for ventilation analysis being performed to evaluate higher airflow rates to support flexible thermal operating range concepts. An analysis is in progress to evaluate the behavior of ground support systems under both low temperature and longer ventilation periods. This analysis will be documented as an ICN to Ground Control for Emplacement Drifts for SR ([146022] CRWMS M&O 2000). The analysis includes an evaluation of steel sets and rock bolts as ground support systems and presents a sensitivity evaluation of the design parameters of the ground support system. Also in progress is an evaluation of the longevity of ground support materials to account for both low temperature and longer ventilation periods. The evaluation results will be documented as an ICN to Longevity of Emplacement Drift Ground Support Materials ([150202] CRWMS M&O 2000).4.2.2 Subsurface Design
Work continued on refining gantry concepts presented in Bottom/Side Lift Gantry Conceptual Design ([145672] CRWMS M&O 2000). An analysis is in progress to describe gantry operations in handling waste packages and emplacement pallets in and near the emplacement drifts. Subsurface Transporter Safety Systems Analysis ([149105] CRWMS M&O 2000) supports the SR and concluded that currently available technology can be incorporated into the electronic controls and mechanical systems to ensure that a runaway event can be regarded as a "beyond design basis" event. A summary of this document and an evaluation of external events will be included in an ongoing analysis that will focus on transporter reliability and preclosure safety.4.2.3 ESF and Construction
Site Services and Field Support provided operations and maintenance of the ESF and Busted Butte UZ Test Facility in support of continuing testing activities. The upgrade of the underground portion of the communications systems is complete. The upgrade of the underground lighting system is underway and projected to be complete during FY 2002. Designs for the ESF Switchgear Building redesign and Busted Butte Mineback, were completed during this reporting period. ESF Subsurface Power Distribution and Lighting upgrade drawings were also issued. Operation and maintenance of the ESF and Busted Butte UZ Test Facility will continue in support of testing activities. Facility system upgrades will continue through the remainder of FY 2001. Commencement of pre-construction setup activities for the Thermal Test Alcove (Alcove #10) is anticipated in FY 2001. Excavation of the Thermal Test Alcove is scheduled for the second quarter of FY 2002.4.2.4 EBS Testing
4.2.4.1 Ventilation Testing
Forced ventilation will be used to control host rock and waste package temperatures in emplacement drifts. Ventilation system design will be based on calculations of how much heat can be removed by the ventilation system under a range of conditions. These calculations will be based on ventilation system models. A one-quarter scale test at the DOE Atlas Facility is providing data to validate these ventilation system models and other repository performance models. Data from this test are needed to support design of an effective ventilation system for the potential Yucca Mountain repository. Simulated waste packages are heated, and ventilation is forced through the test pipe at various velocities and temperatures. Heat removed from the simulated waste packages is measured by monitoring the temperature and quantity of air entering and leaving the system. Six tests have been completed in this test system (referred to as Phase 1). The results from Phase 1 are in agreement with the pre-test predictions for temperatures of various test components. Heat removal efficiencies of more than 80 percent were measured at ventilation flow rates greater than or equal to one cubic meter per second, which, when scaled to repository conditions, is consistent with design plans. The one-quarter scale test was reconfigured to enable better control of the inlet air conditions. The reconfiguration will provide data to support validation of numerical models of emplacement drifts at mid-length positions (several hundred meters into an emplacement drift). Three tests with the new configuration have been conducted using different inlet air temperatures. The results are in agreement with the pre-test predictions.4.2.4.2 Column Testing
Thermal-hydrological-chemical crushed tuff column tests were conducted to provide data for geochemical model validation. These tests evaluated the processes by which minerals and salts in tuff can be dissolved and redeposited in an elevated temperature environment. The potential for mineral redistribution is important because it could inhibit drainage from emplacement drifts. Data obtained during the tests were the temperature distribution throughout the column, water inflow, permeability of the crushed tuff before and after the test, the water chemistry in the boiling zone, and the changes in the mineralogy of the tuff particles at different locations in the column. The test program was started in November 1999 at the DOE North Las Vegas facility, and the final test was completed in early 2001. Final geochemical data is currently being obtained for inclusion in the test report.4.2.4.3 Natural Convection Testing
Evaluations of repository postclosure performance will be based partially on natural convection models that predict the distribution of heat and temperatures in the emplacement drifts. The Natural Convection Test series consists of two tests, one at 25-percent scale and one at 44-percent scale, intended to measure the distribution of heat in simulated emplacement drifts. The simulated drifts will contain waste packages and drip shields in potential repository configurations. The objective of these postclosure tests is to provide data for validation of models that predict the heat and mass transfer in the EBS environment, in the absence of active ventilation. Of particular interest is the magnitude of the thermal gradient that could result because of non-uniform thermal loading with the current waste package emplacement design, which could create conditions that induce condensation zones in the drift. During this reporting period, preparatory work for the testing was completed, including development of the test configuration and implementation plan, establishment of a budget, initiation of procurement for test equipment, selection of a test location, and pretest analyses. This preparatory work is necessary to ensure that the test can be implemented on schedule.4.2.4.4 Thermal Conductivity Testing
Repository thermal loading design is dependent on the thermal analysis prediction of temperatures of waste packages and the rock surrounding emplacement drifts. Thermal analysis indicates that predicted temperatures are sensitive to thermal conductivity and specific heat of the host rock. A field program is under way to collect thermal properties data from the Topopah Spring Tuff lower lithophysal unit. Three tests are planned from boreholes that are nominally 10 to 12 m in length. The smallest test consists of two boreholes in the cross drift wall that are oriented 90° relative to each other, and which cross each other about 5 m into the wall. Core samples to support laboratory testing were collected from the two test boreholes. A video log of the boreholes was performed to provide the basis for an estimate of lithophysal content. The boreholes were also logged with an instrument that estimates moisture content.4.3 WASTE FORM
Several members of the Project participated in the DOE-NRC Technical Exchange Meeting, "Thermal Effects on Flow and Evolution of the Near-Field Environment: Key Technical Issues," held January 8-12, 2001, in Pleasanton, California. Revisions to four AMRs are currently in progress. Also, the Project will provide contributions to the FY01 Supplemental Science and Performance Analyses: Vol. 1 (in progress, see Appendix B), the preliminary site suitability evaluation (in progress, see Appendix B), and will work to resolve issues arising out of Rev. 3 of the NRC’s issue resolution status reports. Lesser objectives and tasks are listed in the Technical Work Plan for Waste Form Degradation Process Model Report for SR ([153295] CRWMS M&O 2000, Sections 2 and 3). During this reporting period the Project issued 13 AMRs and five calculations. The In-Package Chemistry for Waste Forms ([153724] BSC 2001) AMR significantly extends the range of calculated in-package chemistries, and accounts for a wide range of potential waste forms proposed for inclusion in the packages. The following AMRs were issued during this reporting period:4.4 WASTE PACKAGE
4.4.1 Reports
The following reports were completed during this reporting period: Disposal Criticality Analysis Methodology Topical Report, Revision 01 ([151986] YMP 2000)–This report was updated and sent to the NRC for review. It addresses the open items from the NRC issued "Safety Evaluation Report for Disposal Criticality Analysis Methodology Topical Report, Revision 0" ([150765] Reamer 2000) for the Disposal Criticality Analysis Methodology Topical Report Revision 0 ([104441] YMP 1998). Waste Package FY-00 Closure Methods Report ([152753] CRWMS M&O 2000)–The objective of the FY 2000 waste package closure weld development task was to develop fabrication techniques and closure weld techniques for the SR waste package design. Residual stresses, as a result of welding, are measured to determine that the annealing methods are acceptable. In addition, two tasks started in FY 1999 were completed. These tasks included alternate method ultrasonic testing and a plasma arc welding method strain study comparison. Alternate techniques for liquid penetrant testing were investigated, as well as construction of three configurations to support the induction heating study. The mockup produced as part of this program will be used as proof of the ongoing induction annealing study. Waste Package Operations Fabrication Process Report ([152104] CRWMS M&O 2000)–The revision to this report documents the changes in the design and the lessons learned from the FY 2000 Closure Weld Program. The report incorporates the SR waste package, drip shield, and emplacement pallet designs; it also details the fabrication and inspection methods that are expected to be used in building the disposal container, if the repository is authorized. Waste Package Degradation Process Model Report ([153802] CRWMS M&O 2000)–This report is a crucial element of the long-term postclosure safety strategy for the potential HLW repository at Yucca Mountain. It describes how the slow degradation processes that attack the waste package are modeled. The waste package degradation PMR is one of nine PMRs developed to address the technical basis supporting the TSPA model. The nine PMRs are supported by AMRs that contain more detailed technical information. The waste package is a major component of the EBS and contributes to isolation of HLW during the preclosure and postclosure periods. It also reduces the uncertainties associated with performance of the repository. Therefore, the integrity of the waste package and the drip shield has been designated a principal factor important to the repository safety strategy. The waste package, protected by a drip shield, will be subjected to fewer and slower degradation processes, which will result in enhanced postclosure performance. Important conditions that contribute to the slow but inevitable degradation of the waste package include humidity and temperature in the emplacement drift, chemistry of the dripping water, and the corrosion susceptibility of the waste package materials. Eight process-level models or analyses, four abstraction models, and two engineering calculations were developed and documented in individual AMRs or calculations. The Waste Package Degradation PMR ([153802] CRWMS M&O 2000) provides a summary of process-level and abstraction models, as well as a summary of their utilization in the integrated waste package degradation model which is embedded in the WAPDEG code. External Criticality Risk of Immobilized Plutonium Waste Form in a Geologic Repository ([154317] McClure and Alsaed 2001)–This technical report provides an updated summary of the waste package external criticality-related risk of the Pu disposition in a ceramic waste form, which is being developed and evaluated by DOE’s Office of Fissile Materials Disposition. The ceramic waste form consists of Pu immobilized in ceramic disks, which would be sealed in cans and embedded in HLW glass and sealed in the HLW glass disposal canisters. This approach is known as the can-in-canister concept, which yields canisters externally identical to standard HLW canisters. The cans containing the ceramic disks would occupy approximately 12 percent of the HLW canister volume, while most of the remaining 88 percent of the volume would be occupied by HLW glass. Waste Package Design Sensitivity Report ([154624] Macheret 2001)–The purpose of this technical report is to present the current designs for waste packages and to aid in determining which designs will be evaluated for the SR considerations or the possible LA. The report will also demonstrate how the waste package design will be shown to comply with the applicable design criteria. The evaluations to support SR considerations or the possible LA are based on system description document criteria. The report objective is to determine those system description document criteria for which compliance is to be demonstrated for SR considerations, and to refer to the documents that show compliance. In addition, those system description document criteria for which compliance will be addressed in the possible LA are identified, with a distinction made between the LA Construction Authorization phase and the LA Receive and Possess phase. The scope of this work encompasses the Waste Package Project disciplines for criticality, shielding, structural, and thermal analysis. The Project completed the Evaluation of Codisposal Viability for U-Metal (N-Reactor) DOE-Owned Fuel ([154194] CRWMS M&O 2001)–The report supports the demonstration that DOE SNF from N-Reactor can be viably disposed of in the potential repository. Six of the nine groups of DOE SNF have been evaluated to date.4.4.2 Calculations
The following calculations and input transmittals have been completed to support various reports during this reporting period: Expected Number of Key Blocks throughout the Emplacement Drift ([154797] CRWMS M&O 2000)–The objective of this calculation is to project the number of rocks greater than a specific mass that might be available to fall from the emplacement drift ceiling onto waste packages or drip shields. The calculation is focused directly on the existence of key blocks, that is, large rocks that might fall under certain conditions. Rock fall events and the effectiveness of the ground control structures were not within the scope of this evaluation. The calculation uses the SR layout of the emplacement drifts. Dose Rate Calculations for the 2-MCO/2-DHLW Waste Package ([153040] CRWMS M&O 2000)–The objective of this calculation is to determine the dose rates at the external surfaces of the waste package containing two Hanford DHLW glass canisters and two Hanford MCOs. Each MCO is loaded with the N-Reactor SNF. The information provided by the sketches attached to this calculation is that of the potential design for the waste package type considered in this calculation. The scope of this calculation is limited to reporting dose rates averaged over segments of the waste package radial and axial surfaces and at distances of 1 and 2 m from the waste package surface. The results of this calculation will be used to assess the shielding performance of the waste package engineering design. ANSYS Benchmark of the Single Heater Test ([154801] CRWMS M&O 2000)–The Single Heater Test is the first of three in situ thermal tests included in the site characterization program for the potential nuclear waste repository at Yucca Mountain. The heating phase of the Single Heater Test started in August 1996 and was concluded in May 1997 after nine months of heating. Cooling continued until January 1998, at which time post-test characterization of the test block commenced. Numerous thermal-hydrological-mechanical-chemical sensors monitored the coupled processes in the unsaturated fractured rock mass around the heater. The objective of this calculation was to benchmark a three-dimensional numerical simulation of the thermal behavior of the Single Heater Test and surrounding rock mass against the extensive data set that is available from the test. This calculation supports the waste package thermal design methodology. Two-Dimensional Repository Thermal Design Calculations ([154278] CRWMS M&O 2001)–The objective of this calculation is to determine the temperature field of a two-dimensional slice of a repository under various design parameters to attain drift wall, rock, and waste package surface temperatures, both with and without backfill. The adjusted input parameters are initial heat-generation rate, ventilation efficiency, ventilation duration, backfill thermal conductivity, and ballast/invert thermal conductivity. In addition to these cases, corresponding to normal operating conditions, a range of ventilation-interruption cases, as well as partial drift blockage cases, is investigated. The computation of the operating curves of the repository is then performed for a range of temperature operations. Verification of Energy Balance in the ANSYS V5.4 Thermal Calculations ([154804] CRWMS M&O 2001)–The objective of this calculation is to verify the energy balance of the thermal calculations analyzed by ANSYS V5.4 solver. The scope of this calculation is limited to calculating the energy balance of a two-dimensional repository thermal representation using the temperatures obtained from ANSYS V5.4. The associated activity is the development of engineering evaluations to support the LA design activities. EQ6 Calculation for Chemical Degradation of Pu-Ceramic Waste Packages: Effects of Updated Waste Package and Rates ([154055] CRWMS M&O 2001)–This study presents calculations of the long-term geochemical behavior of waste packages containing Pu-ceramic disks arranged according to the can-in-canister concept; i.e., the cans containing Pu-ceramic disks are embedded in canisters filled with HLW glass. Description of Fracture Systems for External Criticality Reports ([153656] CRWMS M&O 2001)–The objective of this input transmittal is to describe, probabilistically, the main features of the geometry of the fracture system in the vicinity of the repository. This information will be used to determine the quantity of fissile material that could accumulate in the fractured rock underneath a waste package as it degrades. External Accumulation of Fissile Material from Waste Packages Containing Plutonium Ceramics: Updated Model ([154056] BSC 2001)–The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures and lithophysae in the rock beneath waste packages containing Pu ceramics as they degrade in the potential repository at Yucca Mountain. Thermal Loading Study of 21-PWR Waste Package ([154754] BSC 2001)–The objective of this calculation is to evaluate the thermal response of the 21-PWR (pressurized water reactor) uncanistered fuel waste package subject to differing fuel assembly loading arrangements. The scope of this calculation is limited to a two-dimensional representation of the waste package interior region over an emplacement period of 10,000 years. Waste Package Tip-Over of 5-DHLW/DOE SNF Short ([154755] BSC 2001)–The objective of this calculation was to determine the structural response of the 5-DHLW/DOE SNF short waste package loaded with five, 10-foot long DHLW canisters and one DOE SNF canister and subjected to tip-over onto an unyielding surface. The scope of this calculation was limited to reporting the calculation results in terms of maximum stress intensities. External Criticality Evaluation of the Plutonium Disposition Ceramic Waste Form ([153962] BSC 2001)–The principal objective of this input transmittal is to evaluate the possibility of criticality of those configurations having significant accumulation of fissile material external to the waste package containing Pu ceramic waste forms. For those configurations found to be critical, the probability of a criticality occurrence was found to be extremely low (one event in 230 billion years).4.4.3 Materials Testing
The container materials testing effort is continuing to generate data and analyses relevant to the performance of the waste package and drip shield materials under expected Yucca Mountain repository conditions. In September 2000, a meeting was held between the Project and the NRC technical staff to review and discuss the list of KTIs. During this meeting, a plan for the path forward to LA was advanced. This resulted in changes in priorities among the different activities in the container materials testing effort, and necessitated re-planning the testing effort, which has been a major activity in the past six months. Another factor in the re-planning effort is the impact of a flexible repository design on the performance of these materials. The path forward and re-planning of testing activities were also discussed at the NWTRB meeting in January 2001. Progress in the last six months includes fabrication of four new vessels for the long-term corrosion test facility. These vessels are being installed and will be used for testing in new test environments and for a number of different types of self-loaded specimens for determining SCC susceptibility. Work is underway in evaluating the environments that will contact the drip shield and waste package outer barrier. These environments result from evaporative concentration and deliquescence effects of concentrated ionic salts and dust components on the surfaces of these metal components. Microbiological activity in these types of environments is being investigated, as is how this activity may influence metal corrosion. The role of minor components in the repository environment is under investigation; some of these components may accelerate corrosion, while others may inhibit it. Work continued on evaluation of effects of water-rock interaction on engineered barrier system materials. Project scientists and engineers collaborated on the design of protocols for the collection and analysis of dust in the ESF. The ESF dust study was prompted by a request from the Subsurface Performance Modeling Section for geochemical and mineralogical characterization of ESF dust that could be analogous to dust that might collect on waste packages or drip shields in a potential repository. Approximately 30 to 50 samples of dust will be collected along the ESF from horizontal or near horizontal surfaces. Characterization will include determination of total organic components, measurement of major and minor ionic species, and particle analyses using petrographic and scanning-electron microscopes. Stress corrosion tests have been conducted in some test solutions on Alloy 22 with additions of lead; however, no accelerating effect of Pb (iron) on SCC has been observed to date. The open-circuit corrosion potential has been measured on Alloy 22 test specimens that have been in test (in the long-term test facility) for four years, and on freshly exposed specimens. The purpose is to determine if there are changes, and particularly if the corrosion potential approaches one of the critical potentials for localized corrosion initiation. A comfortably safe margin exists between the corrosion potential measured and the critical potential. A demonstration of the efficacy of laser peening in mitigating residual stresses around welds has shown that a peened region does not undergo SCC, while an adjacent unpeened region shows extensive crack formation. Specimens of 316L stainless steel (which are highly susceptible to SCC), in boiling concentrated MgCl2 solution, were used for the demonstration. A first-time demonstration of the induction annealing process for mitigating stress on a prototype Alloy 22 container weldment was conducted at a vendor site, but indicated that more developmental work is needed. Evaluation of nickel-iron rich Josephenite as a natural analogue for Alloy 22 indicates that the prolonged existence of the metallic state in the deposits may be explained by protection provided by the magnesium silicate layer that is co-deposited along with the metal during geological events. The following AMRs were updated during this reporting period:SECTION 5 – REPOSITORY PERFORMANCE
During this reporting period the Project accomplished several advances in developing the topics of preclosure radiological safety assessment, postclosure performance assessment, and performance confirmation. These advances are described in the following sections.5.1 PRECLOSURE RADIOLOGICAL SAFETY ASSESSMENT
A revision was made to the Preliminary Preclosure Safety Assessment for Monitored Geologic Repository Site Recommendation ([152153] CRWMS M&O 2000) to include the calculated dose to the lens of the eye. This safety assessment identifies facility hazards and their potential for initiating events, identifies MGR DBEs, evaluates DBE occurrence frequencies and consequences, and identifies those SSCs important to safety. This report also provides the MGR strategies for criticality safety, radiation protection, and fire protection, along with a description of the provisions for the control and management of low-level radioactive waste. Descriptions of the MGR site characteristics and facility design are provided to support the identification of hazards and the evaluation of DBEs. This report supports SR activities. Six classification analyses were revised during the reporting period as a result of changes to the proposed design or architecture of the respective systems. The purpose of classification analyses is to document the QA classification of the MGR SSCs, and provide the basis for the revision of the Q-List ([149733] YMP 2000). The analyses are based on an iterative design classification process. The best available system design and the preliminary DBE analyses are considered when determining which SSCs require design control under the QA program. Features required to meet radiological safety (preclosure) or waste isolation (postclosure) functions are considered in these analyses. The following classification analyses were revised:5.2 POSTCLOSURE PERFORMANCE ASSESSMENT
5.2.1 Performance Assessment
A significant milestone was achieved this reporting period in the area of postclosure performance assessment with the issuance of the Total System Performance Assessment (TSPA) Model for Site Recommendation ([148384] CRWMS M&O 2000). The model document describes the integration of information that represents different aspects of the repository into one comprehensive model. The Yucca Mountain system has been divided into individual parts (process areas) to make the overall system analyses manageable. The model uses a qualified version of the total system simulator, GoldSim (V6.04 STN: 10344-6.04.007-00) ([151202] Golder Associates), to integrate the individual process area models. The TSPA-SR document ([153246] CRWMS M&O 2000) was also revised during this reporting period. This technical document reports the results of the TSPA-SR model presented in the Total System Performance Assessment (TSPA) Model for Site Recommendation ([148384] CRWMS M&O 2000). In addition, the technical document addresses sensitivity studies for each of the TSPA components to understand how uncertainty in various parameters within a component affect the TSPA results. This version of the TSPA-SR document ([153246] CRWMS M&O 2000) incorporated an updated climate model for 1,000,000-year simulations and additional analyses on the effect of secondary mineral phases on radionuclide solubility. A multimedia compact disc presenting a summary of the TSPA-SR document ([153246] CRWMS M&O 2000) was produced. The compact disc has been demonstrated at various conferences and international meetings and the contents made available on the DOE information bridge maintained by the Office of Scientific and Technical Information.5.2.2 Near-Field Environment
Presentations were made to the NRC at the technical exchange meeting in January 2001, which addressed thermal-hydrological and coupled processes on seepage and near-field environment. Presentations were also made to the NRC at the technical exchange meeting in February 2001 (on EBS), including thermal-hydrological-mechanical methodology, results, and validation. The Near Field Environment Process Model Report ([153363] CRWMS M&O 2000) was updated during this period. The following AMRs were issued during this period:5.2.3 Engineered Barrier System
Presentations were made to the NRC at the technical exchange meeting in February 2001, which addressed repository design and thermal-mechanical effects. Presentations were also made to the NRC at the technical exchange meeting in January 2001, which addressed thermal effects on flow. The following AMRs were updated during this period:5.2.4 Unsaturated Zone Flow and Transport
5.2.4.1 Revision of UZ AMRs
The following AMRs were updated during this period:5.2.4.2 UZ Support to FY01 Supplemental Science and Performance Analyses
The focus of the UZ flow and transport modeling investigations has been redirected to the preparation of relevant sections of FY01 Supplemental Science and Performance Analyses: Vol. 1 (in progress, see Section 6 and Appendix B). A number of new models have been set up and numerous simulations performed to support sensitivity analyses of unquantified uncertainties and the flexible operating mode. The results of the numerical simulations have been or are being summarized in Sections 3 (UZ Flow), 4 (Seepage), and 11 (UZ Transport) of FY01 Supplemental Science and Performance Analyses: Vol. 1. Subsections dealing with the flow and transport issues under ambient conditions have been completed. Thermal studies to support the low-temperature design are scheduled for completion by April. Major technical UZ flow and transport issues described and analyzed in the FY01 Supplemental Science and Performance Analyses: Vol. 1 include:5.2.4.3 Interactions with NRC and NWTRB
Several KTI agreement items were completed during the reporting period, including Structural Deformation and Seismicity Subissue 3, Agreement 2; and Radionuclide Transport Subissue 3, Agreement 7. Presentations were made to the NRC at the technical exchange meetings in October, November, and December 2000, and January 2001, which addressed, respectively:5.2.5 Saturated Zone Flow and Transport
Presentations were made to the NRC at the technical exchange meetings in October, November, and December 2000, which addressed, respectively:5.2.6 Biosphere
The following AMRs were updated during this reporting period:5.2.7 Disruptive Events
Presentations were made to the NRC at the technical exchange meetings in October 2000 and February 2001, which addressed, respectively:5.2.8 Waste Package
Presentations were made to the NRC at the technical exchange meetings in January 2001 on the Evolution of Near-Field Environment, and in February 2001 on Repository Design and Thermal-Mechanical Effects. In addition, a presentation was made to the NWTRB on the waste package performance issues. The Waste Package Degradation Process Model Report ([153802] CRWMS M&O 2000) was issued during this period. The following AMRs were issued during this reporting period:5.3 PERFORMANCE CONFIRMATION
The performance confirmation program, which began during site characterization and continues until permanent closure, includes activities to collect and analyze repository performance data to ensure that conditions encountered, and changes in those conditions, are within the limits to be stated in the LA. The performance confirmation program will determine whether the natural systems, engineered systems, and system components function as intended and anticipated. The Performance Confirmation Plan ([150657] CRWMS M&O 2000) and the Monitored Geologic Repository Test & Evaluation Plan ([151965] CRWMS M&O 2000) are being updated. This work will evaluate possible changes in the testing program due to KTI resolution agreements with the NRC, comments from the NWTRB, and from the evolution of the design.SECTION 6 – EPILOGUE
Several important developments, shown here chronologically, have occurred on the Project since the close of the reporting period on March 31, 2001. As of November 21, 2001, these developments include the following:SECTION 7 – REFERENCES
7.1 DOCUMENTS CITED
NOTE: References are cited in text by DIRS number and numerically sorted by DIRS number in this list. The unique DIRS number is placed in the text before the author-date callout (e.g., ([151553] CRWMS M&O 2000), and is shown in the first column of this list.| 104441 | YMP 1998. Disposal Criticality Analysis Methodology Topical Report. YMP/TR-004Q, Rev. 0. Las Vegas, Nevada: Yucca Mountain Site Characterization Office. ACC: MOL.19990210.0236. |
| 105155 | DOE (U.S. Department of Energy) 1999. Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada. DOE/EIS-0250D. Summary, Volumes I and II. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.19990816.0240. |
| 105655 | Dyer, J.R. 1999. "Revised Interim Guidance Pending Issuance of New U.S. Nuclear Regulatory Commission (NRC) Regulations (Revision 01, July 22, 1999), for Yucca Mountain, Nevada." Letter from J.R. Dyer (DOE/YMSCO) to D.R. Wilkins (CRWMS M&O), September 3, 1999, OL&RC:SB-1714, with enclosure, "Interim Guidance Pending Issuance of New NRC Regulations for Yucca Mountain (Revision 01)." ACC: MOL.19990910.0079. |
| 113224 | CRWMS M&O 1999. Rock Properties Model (RPM3.1) Analysis Model Report. MDL-NBS-GS-000004 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.19991027.0207. |
| 130982 | CRWMS M&O 2000. Probability Distribution for Flowing Interval Spacing. ANL-NBS-MD-000003 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000602.0052. |
| 135621 | NRC (U.S. Nuclear Regulatory Commission) 1999. Issue Resolution Status Report Key Technical Issue: Structural Deformation and Seismicity. Rev. 2. Washington, D.C.: U.S. Nuclear Regulatory Commission. ACC: MOL.19991214.0623. |
| 138860 | CRWMS M&O 2000. Geologic Framework Model (GFM3.1). MDL-NBS-GS-000002 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000121.0115. |
| 138960 | CRWMS M&O 2000. Mineralogical Model (MM3.0). MDL-NBS-GS-000003 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000120.0477. |
| 141130 | CRWMS M&O [Civilian Radioactive Waste Management System Management & Operating Contractor] 1999. Report to Update Total System Life Cycle Cost Estimate for Site Recommendation/License Application. TDR-CRW-SE-000001 REV 01. Washington, D.C.: CRWMS M&O. ACC: MOV.19991208.0001. |
| 141399 | CRWMS M&O 2000. Geochemical and Isotopic Constraints on Groundwater Flow Directions, Mixing, and Recharge at Yucca Mountain, Nevada. ANL-NBS-HS-000021 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000918.0287. |
| 144986 | CRWMS M&O 2000. Analysis of Geochemical Data for the Unsaturated Zone. ANL-NBS-HS-000017 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000725.0453. |
| 145560 | YMP 2001. Yucca Mountain Site Characterization Project Requirements Document (YMP-RD). YMP/CM-0025, Rev. 4. Las Vegas, Nevada: Yucca Mountain Site Characterization Office. ACC: MOL.20010322.0491. |
| 145672 | CRWMS M&O 2000. Bottom/Side Lift Gantry Conceptual Design. ANL-WES-ME-000003 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000420.0399. |
| 146022 | CRWMS M&O 2000. Ground Control for Emplacement Drifts for SR. ANL-EBS-GE-000002 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000414.0875. |
| 146023 | CRWMS M&O 2000. Overall Subsurface Ventilation System. ANL-SVS-HV-000002 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000413.0689. |
| 146103 | CRWMS M&O 2000. Emplacement Ventilation System. ANL-SVS-HV-000003 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000413.0688. |
| 146835 | USGS (U.S. Geological Survey) 2000. Hydrogeologic Framework Model for the Saturated-Zone Site-Scale Flow and Transport Model. ANL-NBS-HS-000033 REV 00. Denver, Colorado: U.S. Geological Survey. ACC: MOL.20000802.0010. |
| 148384 | CRWMS M&O 2000. Total System Performance Assessment (TSPA) Model for Site Recommendation. MDL-WIS-PA-000002 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001226.0003. |
| 149105 | CRWMS M&O 2000. Subsurface Transporter Safety Systems Analysis. ANL-WER-ME-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000829.0005. |
| 149733 | YMP 2000. Q-List. YMP/90-55Q, REV 6. Las Vegas, Nevada: Yucca Mountain Site Characterization Office. ACC: MOL.20000510.0177. |
| 149860 | CRWMS M&O 2000. Abstraction of NFE Drift Thermodynamic Environment and Percolation Flux. ANL-EBS-HS-000003 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001206.0143. |
| 149862 | CRWMS M&O 2000. Multiscale Thermohydrologic Model. ANL-EBS-MD-000049 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001208.0062. |
| 150202 | CRWMS M&O 2000. Longevity of Emplacement Drift Ground Support Materials. ANL-EBS-GE-000003 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000414.0874. |
| 150561 | CRWMS M&O 2000. Inventory Abstraction. ANL-WIS-MD-000006 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001130.0002. |
| 150657 | CRWMS M&O 2000. Performance Confirmation Plan. TDR-PCS-SE-000001 REV 01 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000601.0196. |
| 150765 | Reamer, C.W. 2000. "Safety Evaluation Report for Disposal Criticality Analysis Methodology Topical Report, Revision 0." Letter from C.W. Reamer (NRC) to S.J. Brocoum (DOE/OCRWM), June 26, 2000, with enclosure. ACC: MOL.20000919.0157. |
| 151202 | Golder Associates 2000. Software Code: GoldSim. 6.04.007. 10344-6.04.007-00. |
| 151549 | CRWMS M&O 2000. Abstraction of Models of Stress Corrosion Cracking of Drip Shield and Waste Package Outer Barrier and Hydrogen Induced Corrosion of Drip Shield. ANL-EBS-PA-000004 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001213.0065. |
| 151551 | CRWMS M&O 2000. Characterize Framework for Igneous Activity at Yucca Mountain, Nevada. ANL-MGR-GS-000001 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001221.0001. |
| 151552 | CRWMS M&O 2000. Dike Propagation Near Drifts. ANL-WIS-MD-000015 REV 00 ICN 1. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001213.0061. |
| 151553 | CRWMS M&O 2000. Features, Events, and Processes: Disruptive Events. ANL-WIS-MD-000005 REV 00 ICN 1. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001218.0007. |
| 151559 | CRWMS M&O 2000. Hydrogen Induced Cracking of Drip Shield. ANL-EBS-MD-000006 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001025.0100. |
| 151560 | CRWMS M&O 2000. Igneous Consequence Modeling for the TSPA-SR. ANL-WIS-MD-000017 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001204.0022. |
| 151561 | CRWMS M&O 2000. In-Drift Microbial Communities. ANL-EBS-MD-000038 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001213.0066. |
| 151563 | CRWMS M&O 2000. Physical and Chemical Environmental Abstraction Model. ANL-EBS-MD-000046 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001204.0023. |
| 151564 | CRWMS M&O 2000. Stress Corrosion Cracking of the Drip Shield, the Waste Package Outer Barrier, and the Stainless Steel Structural Material. ANL-EBS-MD-000005 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001102.0340. |
| 151566 | CRWMS M&O 2000. WAPDEG Analysis of Waste Package and Drip Shield Degradation. ANL-EBS-PA-000001 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001208.0063. |
| 151568 | CRWMS M&O 2000. Environment on the Surfaces of the Drip Shield and Waste Package Outer Barrier. ANL-EBS-MD-000001 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001219.0080. |
| 151635 | CRWMS M&O 2000. Drift Degradation Analysis. ANL-EBS-MD-000027 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001206.0006. |
| 151662 | CRWMS M&O 2001. Clad Degradation – Summary and Abstraction. ANL-WIS-MD-000007 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010214.0229. |
| 151951 | CRWMS M&O 2000. Engineered Barrier System: Physical and Chemical Environment Model. ANL-EBS-MD-000033 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001228.0081. |
| 151964 | CRWMS M&O 2000. Thermal Tests Thermal-Hydrological Analyses/Model Report. ANL-NBS-TH-000001 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010109.0004. |
| 151965 | CRWMS M&O 2000. Monitored Geologic Repository Test & Evaluation Plan. TDR-MGR-SE-000010 REV 03. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20000926.0296. |
| 151968 | CRWMS M&O 2000. Disruptive Events Process Model Report. TDR-NBS-MD-000002 REV 00 ICN 02. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001220.0047. |
| 151986 | YMP 2000. Disposal Criticality Analysis Methodology Topical Report. YMP/TR-004Q, Rev. 01. Las Vegas, Nevada: Yucca Mountain Site Characterization Office. ACC: MOL.20001214.0001. |
| 152016 | CRWMS M&O 2001. Water Distribution and Removal Model. ANL-EBS-MD-000032 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010214.0031. |
| 152076 | CRWMS M&O 1999. Report on Assessment of Fee Adequacy Based on FY 1999 TSLCC Update. TDR-CRW-SE-000003 REV 01. Washington, D.C.: CRWMS M&O. ACC: MOV.19991221.0011. |
| 152104 | CRWMS M&O 2000. Waste Package Operations Fabrication Process Report, TDR-EBS-ND-000003 REV 01. Las Vegas Nevada: CRWMS M&O. ACC: MOL.20000927.0002. |
| 152128 | CRWMS M&O 2000. DSNF and Other Waste Form Degradation Abstraction. ANL-WIS-MD-000004 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001201.0023. |
| 152153 | CRWMS M&O 2000. Preliminary Preclosure Safety Assessment for Monitored Geologic Repository Site Recommendation. TDR-MGR-SE-000009 REV 00 ICN 02. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001113.0307. |
| 152259 | CRWMS M&O 2000. Modeling Sub Gridblock Scale Dispersion in Three-Dimensional Heterogeneous Fractured Media (S0015). ANL-NBS-HS-000022 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001107.0376. |
| 152434 | CRWMS M&O 2001. Environmental Transport Parameter Analysis. ANL-MGR-MD-000007 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010208.0001. |
| 152438 | CRWMS M&O 2000. Input Parameter Values for External and Inhalation Radiation Exposure Analysis. ANL-MGR-MD-000001 REV 01 ICN 00 ICN 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001122.0005. |
| 152517 | CRWMS M&O 2001. Evaluate Soil/Radionuclide Removal by Erosion and Leaching. ANL-NBS-MD-000009 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010214.0032. |
| 152536 | CRWMS M&O 2001. Disruptive Event Biosphere Dose Conversion Factor Analysis. ANL-MGR-MD-000003 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010125.0233. |
| 152539 | CRWMS M&O 2001. Nominal Performance Biosphere Dose Conversion Factor Analysis. ANL-MGR-MD-000009 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010123.0123. |
| 152574 | Cohon, J.L. 2000. Comments of Nuclear Waste Technical Review Board on Meeting of August 1 and 2, 2000, in Carson City, Nevada. Letter from J.L. Cohon (NWTRB) to I. Itkin (DOE/OCRWM), September 20, 2000, with attachments. ACC: MOL.20001019.0136. |
| 152753 | CRWMS M&O 2000. Waste Package FY-00 Closure Methods Report. TDR-EBS-ND-000005 REV 00. Las Vegas Nevada: CRWMS M&O. ACC: MOL.20001002.0149. |
| 152985 | DOE (U.S. Department of Energy) 2001. Supplement to the Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada. DOE/EIS-0250D-S. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20010524.0184. |
| 152998 | CRWMS M&O 2000. Comparison of ASHPLUME Model Results to Representative Tephra Fall Deposits. CAL-WIS-MD-000011 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001204.0032. |
| 153001 | CRWMS M&O 2001. Engineered Barrier System Features, Events, and Processes. ANL-WIS-PA-000002 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010312.0024. |
| 153040 | CRWMS M&O 2000. Dose Rate Calculations for the 2-MCO/2-DHLW Waste Package. CAL-DDC-NU-000012 REV 00. Las Vegas, NV: CRWMS M&O. ACC: MOL.20001016.0006. |
| 153045 | CRWMS M&O 2001. Seepage Calibration Model and Seepage Testing Data. MDL-NBS-HS-000004 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010122.0093. |
| 153097 | CRWMS M&O 2000. Number of Waste Packages Hit by Igneous Intrusion. CAL-WIS-PA-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001220.0041. |
| 153104 | CRWMS M&O 2000. Abstraction of Flow Fields for TSPA. ANL-NBS-HS-000023 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001208.0060. |
| 153168 | CRWMS M&O 2000. Saturated Zone Flow and Transport Process Model Report. TDR-NBS-HS-000001 REV 00 ICN 02. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001102.0067. |
| 153206 | CRWMS M&O 2001. Abstraction of BDCF Distributions for Irrigation Periods. ANL-NBS-MD-000007 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010201.0027. |
| 153207 | CRWMS M&O 2001. Distribution Fitting to the Stochastic BDCF Data. ANL-NBS-MD-000008 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010221.0148. |
| 153246 | CRWMS M&O 2000. Total System Performance Assessment for the Site Recommendation. TDR-WIS-PA-000001 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001220.0045. |
| 153255 | DOE 2001. Analysis of the Total System Life Cycle Cost of the Civilian Radioactive Waste Management Program. DOE/RW-0533. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20010802.0217. |
| 153257 | DOE 2001. Nuclear Waste Fund Fee Adequacy: An Assessment. DOE/RW-0534. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOV.20010607.0015. |
| 153265 | CRWMS M&O 2001. In-Drift Precipitates/Salts Analysis. ANL-EBS-MD-000045 REV 00 ICN 02. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010220.0008. |
| 153271 | CRWMS M&O 2001. Classification of the MGR Waste Emplacement/Retrieval System. ANL-WES-SE-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010227.0016. |
| 153295 | CRWMS M&O 2000. Technical Work Plan for Waste Form Degradation Process Model Report for SR. TWP-EBS-MD-000006 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001204.0036. |
| 153314 | CRWMS M&O 2000. Seepage Model for PA Including Drift Collapse. MDL-NBS-HS-000002 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010221.0147. |
| 153342 | CRWMS M&O 2001. Identification of the Critical Group (Consumption of Locally Produced Food and Tap Water). ANL-MGR-MD-000005 REV 01 ICN 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010119.0109. |
| 153363 | CRWMS M&O 2000. Near Field Environment Process Model Report. TDR-NBS-MD-000001 REV 00 ICN 03. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001121.0041. |
| 153656 | CRWMS M&O 2001. Description of Fracture Systems for External Criticality Reports. Input Transmittal 00416.T. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010117.0017. |
| 153681 | CRWMS M&O 2001. Monitored Geologic Repository Project Description Document. TDR-MGR-SE-000004 REV 02 ICN 01. Las Vegas, NV: CRWMS M&O. ACC: MOL.20010212.0296. |
| 153724 | BSC 2001a. In-Package Chemistry for Waste Forms. ANL-EBS-MD-000056 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010322.0490. |
| 153802 | CRWMS M&O 2000. Waste Package Degradation Process Model Report. TDR-WIS-MD-000002, REV 00 ICN 02. Las Vegas Nevada: CRWMS M&O. ACC: MOL.20001228.0229. |
| 153846 | CRWMS M&O 2001. Defense High Level Waste Glass Degradation. ANL-EBS-MD-000016 REV 00 ICN 1. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010130.0004. |
| 153849 | DOE 2001. Yucca Mountain Science and Engineering Report. DOE/RW-0539. [Washington, D.C.]: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20010524.0272. |
| 153921 | BSC 2001. Evaluation of the Applicability of Biosphere-Related Features, Events, and Processes (FEP). ANL-MGR-MD-000011 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010226.0003. |
| 153931 | CRWMS M&O 2001. Features, Events, and Processes in SZ Flow and Transport. ANL-NBS-MD-000002 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010214.0230. |
| 153933 | CRWMS M&O 2001. Waste Form Colloid-Associated Concentrations Limits: Abstraction and Summary. ANL-WIS-MD-000012 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010130.0002. |
| 153935 | CRWMS M&O 2001. Features, Events, and Processes in Thermal Hydrology and Coupled Processes. ANL-NBS-MD-000004 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010220.0007. |
| 153937 | CRWMS M&O 2001. FEPs Screening of Processes and Issues in Drip Shield and Waste Package Degradation. ANL-EBS-PA-000002 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010216.0004. |
| 153938 | CRWMS M&O 2001. Miscellaneous Waste-Form FEPs. ANL-WIS-MD-000009 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010216.0006 |
| 153940 | CRWMS M&O 2000. EBS Radionuclide Transport Abstraction. ANL-WIS-PA-000001 REV 00 ICN 02. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001204.0029. |
| 153947 | CRWMS M&O 2000. Clad Degradation – FEPs Screening Arguments. ANL-WIS-MD-000008 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001208.0061. |
| 153962 | BSC 2001. External Criticality Evaluation of the Plutonium Disposition Ceramic Waste Form. Input Transmittal 00437.T. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010308.0198. |
| 153982 | USGS (Geological Society of America) 2000. Geologic and Geophysical Characterization Studies of Yucca Mountain, Nevada, A Potential High-Level Radioactive-Waste Repository. Version 1.0. DDS-058. [Denver, Colorado]: U.S. Geological Survey. TIC: 249438. |
| 154024 | CRWMS M&O 2001. Unsaturated Zone and Saturated Zone Transport Properties (U0100). ANL-NBS-HS-000019 REV 00 ICN 1. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010201.0026. |
| 154055 | CRWMS M&O 2001. EQ6 Calculation for Chemical Degradation of Pu-Ceramic Waste Packages: Effects of Updated Waste Package and Rates. Input Transmittal 00434.T. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010302.0005. |
| 154056 | BSC 2001. External Accumulation of Fissile Material from Waste Packages Containing Plutonium Ceramics: Updated Model. Input Transmittal 00433.T. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010302.0006. |
| 154071 | CRWMS M&O 2001. Colloid-Associated Radionuclide Concentration Limits: ANL. ANL-EBS-MD-000020 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010216.0003. |
| 154194 | CRWMS M&O 2001. Evaluation of Codisposal Viability for U-Metal (N-Reactor) DOE-Owned Fuel. TDR-EDC-NU-000004 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010314.0004. |
| 154227 | DOE 2000. Civilian Radioactive Waste Management System Requirements Document. DOE/RW-0406, Rev. 05, DCN 02. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20010117.0341. |
| 154268 | CRWMS-M&O 2001. Classification of the MGR Emplacement Drift System. ANL-EDS-SE-000001 REV 01. Las Vegas, Nevada: CRWMS-M&O. ACC: MOL.20010227.0043. |
| 154278 | CRWMS M&O 2001. Two-dimensional Repository Thermal Design Calculations. CAL-WIS-TH-000001 REV 01. Las Vegas Nevada: CRWMS M&O. ACC: MOL.20010302.0003. |
| 154286 | CRWMS M&O 2001. Summary of Dissolved Concentration Limits. ANL-WIS-MD-000010 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010223.0061. |
| 154291 | CRWMS M&O 2001. Abstraction of Drift Seepage. ANL-NBS-MD-000005 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010309.0019. |
| 154317 | McClure, J.A. and Alsaed, A.A. 2001. External Criticality Risk of Immobilized Plutonium Waste Form in a Geologic Repository. TDR-EBS-MD-000019 REV 00. Las Vegas, Nevada: Bechtel SAIC Company. ACC: MOL.20010314.0001. |
| 154412 | Paces, J.B.; Whelan, J.F.; Peterman, Z.E.; Marshall, B.D.; and Neymark, L.A. 2000. "Formation of Calcite and Silica from Percolation in a Hydrologically Unsaturated Setting, Yucca Mountain, Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-259. Boulder, Colorado: Geological Society of America. TIC: 249113. |
| 154414 | Whelan, J.F.; Paces, J.; Neymark, L.; Marshall, B.; Peterman, Z.; Moscati, R.; and Roedder, E. 2000. "Calcite Fluid Inclusion, Paragenetic, and Oxygen Isotopic Records of Thermal Event(s) at Yucca Mountain, Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-259. Boulder, Colorado: Geological Society of America. TIC: 249113. |
| 154415 | Marshall, B.D. and Whelan, J.F. 2000. "Isotope Geochemistry of Calcite Coatings and the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-259. Boulder, Colorado: Geological Society of America. TIC: 249113. |
| 154416 | Wilson, N.S.F.; Cline, J.S.; and Amelin, Y.V. 2001. "Fluid Inclusion Microthermometry and U-Pb Dating Constraints to Fluid Movement Through the Potential Yucca Mountain Nuclear Waste Repository." Preliminary Program and Abstracts, Eleventh Annual V.M. Goldschmidt Conference, May 20-24, 2001, Hot Springs, Virginia, USA. Houston, Texas: Lunar and Planetary Institute. Accessed April 3, 2001. TIC: 249671. http://www.lpi.usra.edu/meetings/gold2001/pdf/3724.pdf. |
| 154426 | CRWMS M&O 2001. Drift-Scale Coupled Processes (DST and THC Seepage) Models. MDL-NBS-HS-000001 REV 01. Las Vegas, Nevada: Bechtel SAIC Company. ACC: MOL.20010314.0003. |
| 154594 | CRWMS M&O 2001. Abstraction of NFE Drift Thermodynamic Environment and Percolation Flux. ANL-EBS-HS-000003 REV 00 ICN 02. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010221.0160. |
| 154620 | BSC 2001. In-Package Chemistry Abstraction. ANL-EBS-MD-000037 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010315.0053. |
| 154624 | Macheret, P. 2001. Waste Package Design Sensitivity Report. TDR-EBS-MD-000008 REV 01. Las Vegas, Nevada: Bechtel SAIC Company. ACC: MOL.20010313.0506. |
| 154627 | CRWMS M&O 2001. Hydride-Related Degradation of SNF Cladding Under Repository Conditions. ANL-EBS-MD-000011 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010117.0019. |
| 154629 | CRWMS M&O 2001. Pure Phase Solubility Limits - LANL. ANL-EBS-MD-000017 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010126.0005. |
| 154659 | BSC (Bechtel SAIC Company) 2001. FY01 Supplemental Science and Performance Analyses, Volume 2: Performance Analyses. TDR-MGR-PA-000001 REV 00. Las Vegas, Nevada: Bechtel SAIC Company. ACC: MOL.20010724.0110. |
| 154682 | CRWMS M&O 2000. OCRWM Licensing Support Network Management & Operating Contractor Program Plan. PLN-ADS-MD-000001 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010404.0300. |
| 154754 | BSC 2001. Thermal Loading Study of 21-PWR Waste Package. CAL-UDC-TH-000003 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010409.0177. |
| 154755 | BSC 2001. Waste Package Tip-Over of 5-DHLW/DOE SNF Short. CAL-DDC-ME-000004 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010405.0015. |
| 154771 | DOE (U.S. Department of Energy) 2001. Reference Design Description for a Geologic Repository. TDR-MGR-SE-000008 Rev 03 ICN 02 [North Las Vegas, Nevada]: Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20010206.0156. |
| 154796 | CRWMS M&O 2001. Data Qualification Plan for X-Ray Diffraction Mineral Abundance Data for Use on the Yucca Mountain Project. DQP-NBS-HS-000003 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010212.0294. |
| 154797 | CRWMS M&O 2000. Expected Number of Key Blocks throughout the Emplacement Drift. CAL-EBS-MD-000012 REV 00. Las Vegas, NV: CRWMS M&O. ACC: MOL.20001102.0064. |
| 154801 | CRWMS M&O 2000. ANSYS Benchmark of the Single Heater Test. CAL-WIS-TH-000003 REV 00. Las Vegas, NV: CRWMS M&O. ACC: MOL.20010308.0155. |
| 154803 | CRWMS M&O 2001. Site Recommendation Subsurface Layout. ANL-SFS-MG-000001 REV 00 ICN 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010319.0015. |
| 154804 | CRWMS M&O 2001. Verification of Energy Balance in the ANSYS V5.4 Thermal Calculations. CAL-WIS-TH-000009 REV 00. Las Vegas Nevada: CRWMS M&O. ACC: MOL.20010223.0062. |
| 154805 | DOE 2001. Civilian Radioactive Waste Management System Requirements Document. DOE/RW-0406, Rev. 05, DCN 03. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20010409.0176. |
| 154809 | CRWMS M&O 2000. Plutonium/High-Level Vitrified Waste BDBE Dose Calculation. CAL-WPS-SE-000005 REV 00. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20001222.0268. |
| 154810 | CRWMS M&O 2001. Classification of the MGR Waste Package Remediation System. ANL-WPR-SE-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010227.0117. |
| 154811 | CRWMS M&O 2001. Classification of the MGR Waste Handling Building Ventilation System. ANL-HBV-SE-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010227.0044. |
| 154812 | CRWMS M&O 2001. Classification of the MGR Carrier/Cask Handling System. ANL-CCH-SE-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010227.0041. |
| 154813 | CRWMS M&O 2001. Classification of the MGR Carrier Preparation Building Materials Handling System. ANL-CMH-SE-000001 REV 01. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010227.0042. |
| 154827 | Patterson, G.L. 2000. "Low-Level Measurements of Tritium in the Unsaturated Zone from the Exploratory Studies Facility Beneath Yucca Mountain, Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-479-A-480. Boulder, Colorado: Geological Society of America, Inc. TIC: 249113. |
| 154828 | Neymark, L.A.; Amelin, Y.V.; Paces, J.B.; Whelan, J.F.; and Peterman, Z.E. 2000. "U-Pb Dating of Opal and Chalcedony Above and Below the Modern Water Table at Yucca Mountain, Southern Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-259. Boulder, Colorado: Geological Society of America, Inc. TIC: 249113. |
| 154829 | Zhou, X; Stetzenbach, K.J.; Farnham, I.M.; Guo, C.; Lindley, K. 2000. "Trace Element and REE Geochemistry of Groundwaters from Nye County Wells, Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-188. Boulder, Colorado: Geological Society of America. TIC: 249113. |
| 154951 | CRWMS M&O 2001. Repository Safety Strategy: Plan to Prepare the Safety Case to Support Yucca Mountain Site Recommendation and Licensing Considerations. TDR-WIS-RL-000001 REV 04 ICN 01. Two volumes. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.20010329.0825. |
| 155153 | Peterman, Z.E. and Patterson, G.L., 2000. "Saturated Zone Flowpaths Based on Hydrochemical and Isotopic Data From Ground Water in the Yucca Mountain Area, Nevada." Abstracts with Programs - Geological Society of America, 32, (7), A-520. Boulder, Colorado: Geological Society of America, Inc. TIC: 249113. |
| 155188 | IAEA (International Atomic Energy Agency) 2001. An International Peer Review of the Biosphere Modelling Programme of the U.S. Department of Energy’s Yucca Mountain Site Characterization Project: Report of the IAEA International Review Team. Vienna, Austria: International Atomic Energy Agency. TIC: 250092. |
| 155197 | Harbaugh, A.W.; Banta, E.R.; Hill, M.C.; and McDonald, M.G. 2000. MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model—User Guide to Modularization Concepts and the Ground-Water Flow Process. Open-File Report 00-92. Reston, Virginia: U.S. Geological Survey. On Order Library Tracking Number-250197. |
| 155426 | Wilson, N.S.F. and Cline, J.S. 2001. "Paragenesis, Temperature and Timing of Secondary Minerals at Yucca Mountain." "BACK TO THE FUTURE - Managing the Back End of the Nuclear Fuel Cycle to Create a More Secure Energy Future," Proceedings of the 9th International High-Level Radioactive Waste Management Conference (IHLRWM), April 29 - May 3, 2001, Las Vegas, Nevada. La Grange Park, Illinois: American Nuclear Society. TIC: 247873. |
| 155734 | DOE (U.S. Department of Energy) 2001. Yucca Mountain Preliminary Site Suitability Evaluation. DOE/RW-0540. Washington, D.C.: U.S. Department of Energy, Office of Civilian Radioactive Waste Management. ACC: MOL.20011101.0082. |
| 155950 | BSC (Bechtel SAIC Company) 2001. FY 01 Supplemental Science and Performance Analyses, Volume 1: Scientific Bases and Analyses. TDR-MGR-MD-000007 REV 00 ICN 01. Las Vegas, Nevada: Bechtel SAIC Company. ACC: MOL.20010801.0404; MOL.20010712.0062; MOL.20010815.0001. |
| 156406 | Beavers, J.A.; Devine, T.M., Jr.; Frankel, G.S.; Jones, R.H.; Kelly R.G.; Latanision, R.M.; and Payer, J.H. 2001. Interim Report, Waste Package Materials Performance Peer Review Panel, September 4, 2001. [Las Vegas, Nevada]: Waste Package Materials Performance Peer Review Panel. ACC: MOL.20011003.0369. |
| 156976 | 66 FR 57049. Office of Civilian Radioactive Waste Management; Site Recommendation Consideration Process-Announcement of Supplemental Public Comment Period. TIC: Readily Available. |
| 157061 | 66 FR 49372. Site Recommendation Consideration Hearings; Yucca Mountain-Announcement of Changes in Public Hearings. TIC: Readily available. |
| 157062 | 66 FR 58460. Office of Civilian Radioactive Waste Management; Site Recommendation Consideration Process-Announcement of Public Hearings on Supplemental Information. TIC: Readily available. |
7.2 CODES, STANDARDS, AND REGULATIONS
| 100017 | Energy Policy Act of 1992. Public Law No. 102–486. 106 Stat. 2776. Readily available. |
| 100211 | 61 FR [Federal Register] 66158. General Guidelines for the Recommendation of Sites for Nuclear Waste Repositories. Proposed rule 10 CFR Part 963. Readily available. |
| 101680 | 64 FR 8640. Disposal of High-Level Radioactive Wastes in a Proposed Geologic Repository at Yucca Mountain, Nevada. Proposed rule 10 CFR 63. Readily available. |
| 101681 | Nuclear Waste Policy Act of 1982. 42 U.S.C. 10101 et seq. Readily available. |
| 103537 | 10 CFR [Code of Federal Regulations] 2. Energy: Rules of Practice for Domestic Licensing Proceedings and Issuance of Orders. Readily available. |
| 103540 | 10 CFR 60. Energy: Disposal of High-Level Radioactive Wastes in Geologic Repositories. Readily available. |
| 105065 | 64 FR 46976. Environmental Radiation Protection Standards for Yucca Mountain, Nevada. Proposed 40 CFR 197. Readily available. |
| 124754 | 64 FR 67054. Office of Civilian Radioactive Waste Management; General Guidelines for the Recommendation of Sites for Nuclear Waste Repositories; Yucca Mountain Site Suitability. |
| 155009 | 66 FR 23013. Office of Civilian Radioactive Waste Management; Yucca Mountain Science and Engineering Report; Site Recommendation Consideration and Request for Comment. Readily available. |
| 155238 | 40 CFR 197. Protection of Environment: Public Health and Environmental Radiation Protection Standards for Yucca Mountain, Nevada. Readily available. |
7.3 PROCEDURES
AP-IST-004, Public Release Review, Approval and Distribution of Technical and Non-Technical Products. Readily available.