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Physical and chemical characteristics of topographically affected airflow in an open borehole at Yucca Mountain, Nevada

Description: Borehole UZ6S, on the crest of Yucca Mountain, Nevada Test Site, has exhaled approximately 10{sup 6} m{sup 3} of gas annually during winter months for three successive years. The flow arises from thermal-topographic effects. The average composition of the exhausted gas is: N{sub 2} = 78%, O{sub 2} = 21%, Ar = 0.94%, CO{sub 2} = 0.125%, and CH{sub 4} = 0.2 ppMv. The CO{sub 2} has the following isotopic signature: {sup 14}C = 108.5 percent modern carbon (pmc), and {delta}{sup 13}C = 17.1 per mil. In the thirty-month observation period, there has been a net flux to the atmosphere of approximately 40 m{sup 3} of liquid water and 1150 kg of carbon. The gas flowing from UZ6S appears to originate in the soil and/or shallow unsaturated zone at Yucca Mountain crest. 25 refs., 6 figs., 4 tabs.
Date: December 31, 1989
Creator: Thorstenson, D.C.; Woodward, J.C.; Weeks, E.P. & Haas, H.
Partner: UNT Libraries Government Documents Department

Trace elements in coal: Modes of occurrence analysis. Technical progress report, October 5, 1995--March 31, 1996

Description: CQ, Inc. proposed to quantify the relationship between the modes of occurrence of twelve trace hazardous air pollutants (HAP`s) elements in coal and the degree that each element can be removed by existing and advanced physical and chemical coal cleaning processes. They also proposed to investigate new chemical and biological trace element removal processes, and estimate the concentration and stability of trace elements in coal preparation plant tailings. The ultimate goal of this effort is to produce a software tool that will predict the most amenable integration of processes for select trace element emissions control. In support of this effort, the USGS is performing trace element modes of occurrence analyses on coal samples provided by CQ, Inc. The objective of this work to determine the modes of occurrence of as many as twelve trace HAP`s elements in coal. The HAP`s elements can occur in coal in numerous forms. For example, antimony is generally thought to be present in pyrite, accessory sulfides such as stibnite, and possible organically bound; arsenic is primarily associated with late-stage (epigenetic) pyrite; cadmium with sphalerite; chromium may be organically bound, associated with clays, or contained in chromium-bearing mineral; mercury is thought to occur predominately in epigenetic pyrite; and selenium may be organically bound or associated with pyrite or accessory minerals such as clausthalite and galena. Phase I Characterization of four coals is progressing satisfactorily. One round of selective leaching has been completed, the second is underway. Four samples have been submitted for bulk chemical analysis. SEM and microprobe analysis have been started. Preliminary data are presented in this report.
Date: October 1, 1996
Creator: Palmer, C.A.; Findelman, R.B.; Belkin, H.E. & Crowley, S.S.
Partner: UNT Libraries Government Documents Department

Toxic substances from coal combustion - forms of occurrence analyses. Progress report, April 30, 1996 - November 1, 1996

Description: The Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 program coals have been examined to determine the mode of occurrence of selected trace elements using scanning electron microscopy, microprobe analysis, and experimental leaching procedures. Preliminary microprobe data indicates that the arsenic content of pyrite grains in the Illinois No. 6 and Pittsburgh coals is similar. Pyrite grains observed in the Elkhorn/Hazard coal generally have arsenic concentrations that are slightly higher than those of the Pittsburgh or Illinois No. 6 coals. One pyrite grain observed in the Elkhorn.Hazard coal contained much higher levels of arsenic. Preliminary microprobe analysis and data from leaching experiments indicate the association of arsenic with pyrite in the Pittsburgh and Illinois No. 6 coals. Leaching data fore arsenic in the Elkhorn/Hazard coal, in contrast, is inconclusive and additional data are needed before a definite determination can be made.
Date: December 1, 1996
Creator: Crowley, S.S.; Palmer, C.A.; Kolker, A.; Finkelman, R.B.; Kolb, K.C. & Belkin, H.E.
Partner: UNT Libraries Government Documents Department

Toxic substances from coal combustion - forms of occurrence analyses. Semi-annual report, April 30, 1996--November 1, 1996

Description: The overall objective of this project is to provide analytical support for the Physical Sciences, Inc. (PSI) effort being performed under DOE Contract No. DE-AC22-95101 and entitled `` Toxic Substances from Coal Combustion - A Comprehensive Assessment``. The Pittsburgh Elkhorn/Hazard, and Illinois No. 6 program coals have been examined to determine the mode of occurrence of selected trace elements using scanning electron microscopy, microprobe analysis, and experimental leaching procedures. Preliminary microprobe data indicates that the arsenic content of pyrite grains in the Illinois No. 6 (0.0-0.027 ppm As) and Pittsburgh (0.0-0.080 ppm As) coals is similar. Pyrite grains observed in the Elkhorn/Hazard coal generally have arsenic concentrations (0.0-0.272 wt. %As) that are slightly higher than those of the Pittsburgh or Illinois No. 6 coals. One pyrite grain observed in the Elkhorn/Hazard coal contained much higher levels of arsenic (approximately 2 wt. % As). Preliminary microprobe analyses and data from leaching experiments indicate the association of arsenic with pyrite in the Pittsburgh and Illinois No. 6 coals. Leaching data for arsenic in the Elkhorn/Hazard coal, in contrast, is inconclusive and additional data are needed before a definite determination can be made.
Date: December 1, 1996
Creator: Crowley, S.S.; Palmer, C.A.; Kolker, A.; Finkelman, R.B. & Kolb, K.C.
Partner: UNT Libraries Government Documents Department

Toxic substances from coal combustion -- Forms of occurrence analyses. Technical progress report, April 30--November 1, 1996

Description: The overall objective of this project is to provide analytical support for the Physical Sciences, Inc. (PSI) effort being performed under a DOE Contract. The Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 program coals have been examined to determine the mode of occurrence of selected trace elements using scanning electron microscopy, microprobe analysis, and experimental leaching procedures. Preliminary microprobe data indicates that the arsenic content of pyrite grains in the Illinois No. 6 (0.0--0.027 ppm As) and Pittsburgh (0.0--0.080 ppm As) coals is similar. Pyrite grains observed in the Elkhorn/Hazard coal generally have arsenic concentrations (0.0--0.272 wt.% As) that are slightly higher than those of the Pittsburgh or Illinois No. 6 coals. One pyrite grain observed in the Elkhorn/Hazard coal contained much higher levels of arsenic (approximately 2 wt.% As). Preliminary microprobe analyses and data from leaching experiments indicate the association of arsenic with pyrite in the Pittsburgh and Illinois No. 6 coals. Leaching data for arsenic in the Elkhorn/Hazard coal, in contrast, is inconclusive and additional data are needed before a definite determination can be made.
Date: December 6, 1996
Creator: Crowley, S.S.; Palmer, C.A.; Kolker, A.; Finkelman, R.B.; Kolb, K.C. & Belkin, H.E.
Partner: UNT Libraries Government Documents Department

[US Geological Survey research in radioactive waste disposal, fiscal year 1982:] Hydrology

Description: The objective is to determine present and past hydrologic regimes of the Nevada Test Site and vicinity in order to predict the potential for ground-water transport of radioactive waste from a proposed repository in Yucca Mountain to the accessible environment. Test drilling and hydraulic testing are being conducted in both the saturated and unsaturated zones to characterize in detail the hydrologic regimes of the Yucca Mountain area. Results will be used to interpret potential ground-water flow pathways and bulk hydrogeologic properties of unsaturated and saturated rocks, and to obtain information on the chemistry and age of the ground water. Progress is reported. 1 ref.
Date: January 1, 1984
Creator: Wilson, W.E.
Partner: UNT Libraries Government Documents Department

Miscellaneous investigations series: Bedrock geologic map of the Lone Mountain pluton area, Esmeralda County, Nevada

Description: The joint attitudes were measured in the field and plotted on aerial photos at a scale of 1:24,000. The pluton is intensely jointed, primarily as a result of cooling and movement of the magma within a northwest-trending stress field. Foliation, in general, is poorly developed, and quality varies from area to area, but it is best developed close to the contacts with the metasedimentary rocks. A prominent northwest foliation direction was observed that parallels the northwest elongation of the exposed pluton. Faults in the pluton are difficult to identify because of the homogeneity of the rock. Several faults were mapped in the northern part of the area where they have a northeast trend and intersect the northwest-trending lamprophyre dikes with little apparent displacement. A major fault that bounds the northern part of the pluton is downthrown to the north and strikes northeast. This fault offsets the alluvium, the metasedimentary rocks, and the pluton and forms fault scraps as high as 10 m. Aeromagnetic data (US Geological Survey, 1979) suggest the following: (1) the local magnetic highs in the central part of the Lone Mountain pluton are probably related to topographic highs (peaks) where the flight lines are closer to the pluton; (2) a magnetic low in the northeastern part of Lone Mountain coincides with the pluton-country rock contact, which may be very steep; (3) the contours for the southwestern part of the mapped area indicate that the pluton-country rock contact is not as steep as that in the northeastern part and that the pluton probably coalesces at depth with the Weepah pluton, a pluton exposed south of the mapped area; and (4) the contours for the area of the Lone Mountain pluton express a northwest-trending gradient that parallels the northwest elongation of the Lone Mountain pluton and the northwest-trending stress ...
Date: December 31, 1984
Creator: Maldonado, F.
Partner: UNT Libraries Government Documents Department

Late Tertiary and Quaternary geology of the Tecopa basin, southeastern California

Description: Stratigraphic units in the Tecopa basin, located in southeastern California, provide a framework for interpreting Quaternary climatic change and tectonism along the present Amargosa River. During the late Pliocene and early Pleistocene, a climate that was appreciably wetter than today`s sustained a moderately deep lake in the Tecopa basin. Deposits associated with Lake Tecopa consists of lacustrine mudstone, conglomerate, volcanic ash, and shoreline accumulations of tufa. Age control within the lake deposits is provided by air-fall tephra that are correlated with two ash falls from the Yellowstone caldera and one from the Long Valley caldera. Lake Tecopa occupied a closed basin during the latter part, if not all, of its 2.5-million-year history. Sometime after 0.5 m.y. ago, the lake developed an outlet across Tertiary fanglomerates of the China Ranch Beds leading to the development of a deep canyon at the south end of the basin and establishing a hydrologic link between the northern Amargosa basins and Death Valley. After a period of rapid erosion, the remaining lake beds were covered by alluvial fans that coalesced to form a pediment in the central part of the basin. Holocene deposits consist of unconsolidated sand and gravel in the Amargosa River bed and its deeply incised tributaries, a small playa near Tecopa, alluvial fans without pavements, and small sand dunes. The pavement-capped fan remnants and the Holocene deposits are not faulted or tilted significantly, although basins to the west, such as Death Valley, were tectonically active during the Quaternary. Subsidence of the western basins strongly influenced late Quaternary rates of deposition and erosion in the Tecopa basin.
Date: December 31, 1987
Creator: Hillhouse, J.W.
Partner: UNT Libraries Government Documents Department

Trench logs from a strand of the Rock Valley Fault System, Nevada Test Site, Nye County, Nevada

Description: The Rock Valley fault system trends northeasterly through the southeast corner of the Nevada Test Site. The system records left-lateral offset of Paleozoic and Tertiary rocks, although total offset amounts to only a few kilometers. Distinct scarps in alluvial deposits of Quaternary age and a concentration of seismicity, particularly at its north end, suggest that the Rock Valley fault system may be active. Two trenches were excavated by backhoe in 1978 across a 0.5-m-high scarp produced by a strand of the Rock Valley fault system. A detailed logging of the two Rock Valley fault trenches was undertaken during the spring of 1984. This report presents: (1) logs of both walls of the two trenches, (2) a general description of the lithologic units and the soils formed in these units that are exposed in and near the fault trenches, (3) observations of the clast fabric of unfaulted and faulted deposits exposed in the trench walls, and (4) a map of the surficial deposits in the vicinity of the trenches.
Date: December 31, 1987
Creator: Yount, J.C.; Shroba, R.R.; McMasters, C.R.; Huckins, H.E. & Rodriguez, E.A.
Partner: UNT Libraries Government Documents Department

Preliminary interpretation of thermal data from the Nevada Test Site

Description: Analysis of data from 60 wells in and around the Nevada Test Site, including 16 in the Yucca Mountain area, indicates a thermal regime characterized by large vertical and lateral gradients in heat flow. Estimates of heat flow indicate considerable variation on both regional and local scales. The variations are attributable primarily to hydrologic processes involving interbasin flow with a vertical component of (seepage) velocity (volume flux) of a few mm/yr. Apart from indicating a general downward movement of water at a few mm/yr, the reults from Yucca Mountain are as yet inconclusive. The purpose of the study was to determine the suitability of the area for proposed repository sites.
Date: January 1, 1982
Creator: Sass, J.H. & Lachenbruch, A.H.
Partner: UNT Libraries Government Documents Department

An estimate of the roughness length and displacement height of Sonoran Desert vegetation, south-central Arizona

Description: A somewhat unconventional technique using a tethered balloon was used to estimate the roughness length for momentum (z{sub m}) and displacement height (d) for typical Sonoran Desert vegetation. It has been suggested that measurements of the meteorological fluxes of momentum, sensible heat, and latent heat are best done at heights above ground level determined by either the roughness length (z{sub m}) or the size and shape of vegetation. Therefore, estimates of z{sub m} and vegetation characteristics are a desirable prerequisite to developing a flux-measurement protocol. Because the literature contains little information on z{sub m} for Sonoran Desert vegetation, it is desirable to measure z{sub m} and the displacement height (d) associated with Sonoran Desert vegetation.
Date: December 1, 1993
Creator: Claassen, H.C. & Riggs, A.C.
Partner: UNT Libraries Government Documents Department

Analysis of gaseous-phase stable and radioactive isotopes in the unsaturated zone, Yucca Mountain, Nevada

Description: The Nevada Nuclear Waste Storage Investigations Project of the US Department of Energy provides that agency with data for evaluating volcanic tuff beneath Yucca Mountain, Nevada, to determine its suitability for a potential repository of high-level radioactive waste. Thickness of the unsaturated zone, which consists of fractured, welded and nonwelded tuff, is about 1640 to 2460 feet (500 to 750 meters). One question to be resolved is an estimate of minimum ground-water traveltime from the disturbed zone of the potentail repository to the accessible environment. Another issue is the potential for diffusive or convective gaseous transport of radionuclides from an underground facility in the unsaturated zone to the accessible environment. Gas samples were collected at intervals to a depth of 1200 feet from the unsaturated zone at Yucca Mountain, Nevada. Samples were analyzed for major atmospheric gases; carbon dioxide in the samples was analyzed for carbon-14 activity and for {delta}2!{sup 3}C; water vapor in the samples was analyzed for deuterium and oxygen-18. These data could provide insight into the nature of unsaturated zone transport processes. 15 refs., 4 figs., 4 tabs.
Date: December 31, 1985
Creator: Yang, I.C.; Haas, H.H.; Weeks, E.P. & Thorstenson, D.C.
Partner: UNT Libraries Government Documents Department