Earth Sciences Commons^™

Geostatistical And Stochastic Study Of Flow And Tracer Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Feng Pan, Xiaolong Bill Hu, Jianting Zhu, Amy J. Smiecinski

Publications (YM)

Yucca Mountain has been proposed by the U.S. Department of Energy as the nation’s long-term, permanent geologic repository for spent nuclear fuel or high-level radioactive waste. The potential repository would be located in Yucca Mountain’s unsaturated zone (UZ), which acts as a critical natural barrier delaying arrival of radionuclides to the water table. Since radionuclide transport in groundwater can pose serious threats to human health and the environment, it is important to understand how much and how fast water and radionuclides travel through the UZ to groundwater. The UZ system consists of multiple hydrogeologic units whose hydraulic and geochemical properties …

Influence Of Lithophysal Geometry On The Uniaxial Compression Of Tuff-Like Rock, Douglas B. Rigby, Moses Karakouzian, Amy J. Smiecinski

Publications (YM)

The purpose of this report is to summarize the work and present conclusions of Project Activity Task ORD-FY04-013 conducted under Cooperative Agreement No. DEFC28- 04RW12232 between the U.S. Department of Energy and the Nevada System of Higher Education (NSHE). This document describes results of laboratory testing on analog lithophysal tuff (Hydro-StoneTB®) conducted in the Department of Civil and Environmental Engineering of the University of Nevada at Las Vegas (UNLV) from 2004 to 2006.

Basic Research Needs For Geosciences: Facilitating 21st Century Energy Systems, U.S. Department Of Energy, Office Of Basic Energy Sciences, Donald J. Depaolo, Franklin M. Orr Jr.

Publications (YM)

Executive Summary

Serious challenges must be faced in this century as the world seeks to meet global energy needs and at the same time reduce emissions of greenhouse gases to the atmosphere. Even with a growing energy supply from alternative sources, fossil carbon resources will remain in heavy use and will generate large volumes of carbon dioxide (CO₂). To reduce the atmospheric impact of this fossil energy use, it is necessary to capture and sequester a substantial fraction of the produced CO₂. Subsurface geologic formations offer a potential location for long-term storage of the requisite large …

Longbase Laser Strainmeter Measurements At Yucca Mountain, James N. Brune

Publications (YM)

Why Operate a Strainmeter? To monitor strain over a broader bandwidth and with much higher sensitivity than GPS (or other instruments):
– Measure strain from seismic, earth-tide, temperature and air pressure inputs--gives local rock properties, and changes in them.
– Independently constrains GPS results.

To directly measure in the Yucca Mountain Block:
– Sensitive to potential very local tectonic events, (including any triggered slip), or volcanic events.

To establish a baseline for future strain changes:
– E.g., events developing from loading and heating of the repository

Southern Great Basin Seismic Network Operations, John G. Anderson, Glenn Biasi, Ken Smith, Nevada Seismological Laboratory, University Of Nevada, Reno

Publications (YM)

Subtasks 1. Record and archive data from the permanent seismic network.
2. Process seismic data into a preliminary earthquake bulletin.
3. Maintain the seismic stations, the strong-motion stations, the telemetry network, and the computing lab.
4. Prepare and submit a seismicity report on a yearly basis
5. Maintain and collect data from 3 north-portal boreholes.
6. Report on borehole accelerometers.
7. Estimate Kappa at network stations.
8. Implement a recording system at borehole UZ16.
9. Prepare and submit high-quality papers to peer-reviewed journals on seismic data and interpretations in the YM region.
10. Perform a multi-year telemetry and station upgrade.

Influence Of Lithophysae Geometry On Mechanical Properties Of Hydro-Stone®, Moses Karakouzian, Doug Rigby

Publications (YM)

85 percent of YM drift tunnels will be constructed in lithophysal volcanic tuff.

Rock behavior depends on porosity.

Limited experimental data exists to characterize rock porosity and dependencies on properties such as σc , E, and n.

Precarious Rock Methodology For Seismic Hazard: Physical Testing, Numerical Modeling, And Coherence Studies, Rasool Anooshehpoor, James N. Brune, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The precarious rock methodology used for seismic hazard assessment includes location, age dating, field measurements of the quasi-static toppling acceleration of balanced rocks, and study of their dynamic response to realistic strong motion seismograms using numerical modeling. The work scope is contained in the task description issued by the DOE to the Seismology Laboratory of the University of Nevada, Reno and is itemized in section 2.3 below. In addition, measurement of the coherence of seismic energy at high frequencies, critical to the understanding of the variability of high frequency ground motions at the repository level, will be estimated based on …

Geostatistical And Stochastic Study Of Radio Nuclide Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The U.S. Nuclear Waste Technical Review Board [Cohon et al. 1998] evaluated the technical and scientific validity of activities undertaken by the Secretary of Energy to characterize Yucca Mountain, Nevada, for its suitability as an underground repository in which to store high-level radioactive waste and spent nuclear fuel. In the report, the Board pinpointed that the study on groundwater flow and radionuclide transport in the saturated and unsaturated zones below Yucca Mountain should, over the next several years, focus on reducing prediction uncertainty. In its 2002, the Board repeated this concern by stating, “… hydrogeologic processes that affect radionuclide transport …

Long-Term Mechanical Behavior Of Yucca Mountain Tuff And Its Variability, Jaak J.K. Daemen, Lumin Ma, Guohua Zhao

Publications (YM)

The study of the long term mechanical behavior of Yucca Mountain tuffs is important for several reasons. Long term stability of excavations will affect accessibility (e.g. for inspection purposes), and retrievability. Long term instabilities may induce loading of drip shields and/or emplaced waste, thus affecting drip shield and/or waste package corrosion. Failure of excavations will affect airflow, may affect water flow, and may affect temperature distributions.

The long term mechanical behavior of “hard” rocks remains an elusive topic, loaded with uncertainties. A variety of approaches have been used to improve the understanding of this complex subject, but it is doubtful …

Results Of Chemical Analyses For Alcove 8/ Niche 3 Tracer Studies, Jeanette Daniels, Amy J. Smiecinski

Publications (YM)

This is the final report detailing the analyses performed under ORD-FY04-011 "Chemical Analyses for Alcove 8/Niche 3 Tracer Studies," The work was performed under The University and Community College System of Nevada (UCCSN) and the Department of Energy (DOE) Cooperative Agreement DE-FC28-04RW12232, This task provided method development and analytical support for the Alcove 8/Niche 3 Tracer Studies in the Exploratory Studies Facility (ESF). Concentrations of tracers as well as major anions and cations were reported for samples provided by Lawrence Berkeley National Laboratory (LBNL) and the US Geological Survey (USGS). Samples were analyzed using High Performance Liquid Chromatography (HPLC) and …

Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

We propose to continue the investigation of the long term strength of Yucca Mountain tuffs, with particular emphasis on tuffs from and near the emplacement horizon. We propose to also continue and expand the investigation of the spatial variability of rock strength and stiffness. An intrinsic component of this planned rock testing is the testing of rock joints. Although the emphasis is on tests aimed at determining long term strength, as part of the testing measurements of stiffness also are collected, and will be collected, reported, and analyzed.

Influence Of Lithophysae Geometry And Distribution On Mechanical Properties Of Topopah Spring Tuff, Mohammad Shahidul Islam, Justin Fenton, Moses Karakouzian, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The current Site Recommendation study for the proposed high level nuclear waste repository at Yucca Mountain locates the repository emplacement drifts approximately 81% within the lower lithophysal unit of the Topopah Springs Formation (Tptpll), 4% within the upper lithophysal unit of the Topopah Springs Formation (Tptpul), and roughly 15% within the middle, non-lithophysal unit (Tptpmn) of the same formation. A major geomechanical issue facing the Yucca Mountain Project is to understand the thermomechanical behavior of lithophysal tuff, which comprises roughly 85% of the repository host rock.

Experimental Investigation Of Time Dependent Behavior Of Welded Topopah Spring Tuff, Lumin Ma

Publications (YM)

Four types of laboratory tests have been performed. Specimens were attained from four lithophysal zones of the welded Topopah Spring Tuff unit at Yucca Mountain, Nevada: upper lithophysal, middle nonlithophysal, lower lithophysal and lower nonlithophysal zones. Two types of tests are conducted to study time-dependent behavior: constant strain rate and creep tests. Sixty five specimens from the middle nonlithophysal zone were tested at six strain rates: 10 , 10 , 10 , 10 , 10 , and 10 . Test durations range from 2 seconds to 7 days. Fourteen specimens from middle nonlithophysal, lower lithophysal and lower nonlithophysal zones are …

Point Load Strength Testing Of Irregular Rock Fragments Of Welded Tuff, Jaak J.K. Daemen, George Danko, Amy J. Smiecinski

Publications (YM)

Yucca Mountain is composed of a thick sequence of variably welded and nonwelded ashflow tuffs (Rautman and Engstrom, 1996). The understanding of the rock mechanical properties is useful for characterizing the mechanical stability of the potential repository and for estimating the amount of ground support needed in underground construction (Sweetkind et al, 2003). According to Brook (1993), knowledge of lump point load strength is helpful because it can help in estimating the compressive strength. Lump point load testing is one basic mechanical characterization test to support the study of long term drift stability at the potential High Level Waste repository …

Drift Scale Test: Analyze And Report, George Danko, Davood Bahrami, Amy J. Smiecinski

Publications (YM)

This report summarizes the results of the in situ thermophysical properties measurements as part of the Drift Scale Test (DST) measurement program at Yucca Mountain, Nevada. Thermophysical measurements have been performed with three built-in thermal probes since November 13, 1997 and were expected to continue for three more years until the end of the DST cooling period. The Department of Energy (DOE), under Cooperative Agreement, Number DEFC28- 98NV12081, has funded a research project at the University of Nevada, Reno since November, 1999 titled: "Continuing site characterization and performance verification applications with the REKA method at Yucca Mountain, Task 13." This …

Stress Corrosion Cracking Studies, K. S. Raja, S. Namjoshi, Amy J. Smiecinski

Publications (YM)

This document reports on the activities for Task 17 of the U.S. DOE/UCCSN Cooperative Agreement Number DE-FC28-98NV12081. There are three subtasks in this Task, the experimental results, discussions, and conclusions of which are presented in the following sections. Data Sources and Electronic Data Control The Data Identification numbers for the data, graphs, and tables in this report, as submitted to the Data Management Database, are tabulated below. The table also includes the source files for the said data as well as the corresponding scientific notebooks where the data can be found. All data in the Q section of the report …

Experimental Determination Of Stiffness Of Joints In Welded Tuff, Jaak J.K. Daemen, George Danko, Amy J. Smiecinski

Publications (YM)

Fourteen uniaxial joint compression tests were run to determine the normal and shear stiffnesses of type 1 fracture joints (healed joints filled with vapor-phase mineral deposits) obtained from the Yucca Mountain site. The uniaxial joint compression results show that these joints behave linearly up to over 85% of their loading history. They are stiff with strengths very close to the strength of the intact rock. Five direct shear tests were run on open, separated, joints. Results obtained from the direct shear testing show that the normal stiffness increases with increasing normal stress. Shearing through asperities gives high joint shear stiffness …

Longbase Laser Strainmeter Measurements From The South Ramp Of The Yucca Mountain Facility, Frank K. Wyatt, Duncan C. Agnew, James N. Brune, Amy J. Smiecinski

Publications (YM)

Under subcontract (DOE/UCCSN DE-FC28-98NV12081, Task 7) from the Seismological Laboratory of the University of Nevada-Reno, the University of California, San Diego (UCSD), has designed, installed, and operated a laser strainmeter (LSM) in the Exploratory Studies Facility (ESF) at Yucca Mountain, Nevada. This instrument provides precise deformation monitoring of the (proposed) repository block. This document describes the history of the installation, outlines the principles of operation of the system, documents the integral recording and control system and file formats used, and provides information on how QA has been implemented, with the aim of being a self-contained description which could be used …

The Influence Of Lithophysal Porosity On The In-Situ Stress-Strain Properties Of Topopah Spring Tuff, Bahri B. Avar, Moses Karakouzian, Amy J. Smiecinski

Publications (YM)

Numerical analysis and a laboratory testing program were conducted in order to investigate the effect of lithophysal porosity on the elastic stress-strain properties of the lithophysae-rich tuff specimens and to find the locations of cavities in both analog and tuff specimens. In the first part of the study, a finite difference mesh containing circular holes was modeled for varying porosity ranges between 5 and 40% using commercially available software FLAG20' version 3.5. Elastic (Young's) modulus and Poisson's ratio were calculated for each setup and normalized with respect to matrix elastic modulus and Poisson's ratio. The moduli calculated through numerical analysis …

Thermochronological Evolution Of Calcite Formation At The Potential Yucca Mountain Repository Site, Nevada: Part 2 Fluid Inclusion Analyses And Upb Dating, Jean S. Cline, Amy J. Smiecinski, Robert Bodnar

Publications (YM)

The presence of two-phase fluid inclusions in thin secondary mineral crusts at the potential Yucca Mountain nuclear waste repository has raised questions regarding the origin, timing, and temperature of past fluid flow through the repository horizon. The geologically recent passage of fluids with high temperatures would call into question the suitability of the site for the storage of high level nuclear waste. This study determined the thermal history of fluid flow through the site using fluid inclusion analyses and constrained the timing of thermal fluids by dating silica minerals spatially associated with the fluid inclusions using U-Pb techniques. Results provide …

Influence Of Lithophysal Porosity On Stress-Strain Properties Of Topopah Spring Tuff - Numerical Analysis, Nick Hudyma, Moses Karakouzian, Amy J. Smiecinski

Publications (YM)

The purpose of the numerical analysis effort of Task 27 of cooperative agreement DE-FC08-98NV12081 was to investigate the effect of lithophysal porosity on the elastic stress-strain properties of the tuff rock mass. Rock mass properties without lithophysal cavities are designated matrix properties. Rock mass properties with lithophysal cavities are designated effective properties. The analysis will be performed for a 6" by 6" square cross-section with a uniform distribution of lithophysal cavities for a variety of porosities. The analyses will be performed using FLAG 2D version 3.5, a Department of Energy qualified software. The analyses will compare the matrix properties to …