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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Surface Water Impacts from Active Underground Mining

Kirby, Laura Rebecca 03 July 2013 (has links)
High extraction mining techniques have produced the need to mitigate and understand ground movements associated with this technology.  Tools such as the Surface Deformation Prediction System (SDPS) facilitate sound scientific decision making in the industry and has continually improved since its inception in 1987.  The capabilities of SDPS have expanded on an as-needed basis.  Currently, the regulatory climate has emphasized the need to understand the impact of underground mining on surface waters, physically and chemically. The SDPS program is used to conduct an analysis of ground movements to assess optimal barrier pillar size for stream protection.  Typical analytical and empirical methods used in mine planning were compared against SDPS methods to ensure the validity and advantage to the use of SDPS for this purpose. Finally, underground mining effects on stream chemistry and health were explored by studying the heavily mined and industrialized watershed of Dumps Creek located in Russell County, Virginia.  This watershed has been identified as being impaired since the Virginia 303(d) List of Impaired Waters was created in 1994.  Currently, there are two pumps staged in the headwaters region of Dumps Creek that help to maintain water levels in an inactive underground mine.  The pumping is necessary to control methane levels that rising water could force into an active underground mine that lies stratigraphically above the inactive mine.  Water is pumped on an as-needed basis and discharges directly into Dumps Creek.  Historic measurements of stream conductivity and benthic health scores were compared to assess whether a correlation exists between the two measurements.  These measurements were compared based on regulatory decisions that emphasized that conductivity is a direct indicator of stream health in all watersheds. Scientific contributions associated with this research include: Further developments in the use of SDPS programming in order to account for stream protection on a case by case basis for both mine panel and surface water protection by optimizing barrier pillar size in relation to a nearby stream; the analysis of available and currently obtained water chemistry data in a mining impacted watershed in attempt to further research to appropriately characterize and mitigate specific problems in order to improve stream health; and, assessment of the complexity of water chemistry impacts from underground mining as related to stream health indicators in different chemically dominated watersheds. / Master of Science
52

Analysis of Riparian Forest and Floodplain Quality in the Yellow Creek Watershed: Using the Qualitative Habitat Evaluation Index

Williamson, Robert A. January 1999 (has links)
No description available.
53

An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability

Mor��t, Stephanie L. 04 November 1997 (has links)
Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. / Graduation date: 1998
54

From one to many, from many to one : speech communities in the Muskogee stompdance population /

Innes, Pamela Joan. January 1997 (has links)
Thesis (Ph. D.)--University of Oklahoma, 1997. / Includes bibliographical references.
55

Relationships among several breccia pipes and a lead-silver vein in the Copper Creek Mining District, Pinal County, Arizona

Walker, Valerie-Anne January 1979 (has links)
No description available.
56

Sacred people, a world of change the enduring spirit of the Creek and Cherokee on the frontier /

Greenbaum, Marjory Grayson-Lowman. January 2005 (has links)
Thesis (M.A.)--Georgia State University, 2005. / Title from thesis t.p. Clifford Kuhn, committee chair; Charles G. Steffen, committee member. Electronic text (17 p.) : digital, PDF file. Electronic audio (58:41 and 30:53 min.) : digital, AAC Audio file. "The interviews were aired on Atlanta public radio in the form of short segments for Native American History Month and later for a series of vignettes I produced that highlighted advocates for human rights called Voices for Freedom"--P. 5. Description based on contents viewed Aug. 3, 2007.
57

A Quantitative and Qualitative Bacterial Analysis of Pecan Creek

Cook, Vernice January 1946 (has links)
Since Pecan Creek receives sewage wastes from an obviously inadequate disposal system, it seemed possible that it could receive pathogenic bacteria. The fact that these might be present in numbers sufficient to cause epidemics, provided the proper natural vectors were present, stimulated an interest in and the pursuance of this study.
58

Physiological Ecology, Population Genetic Responses and Assemblage Stability of Fishes in Two Southwestern Intermittent Stream Systems

Rutledge, Charles Jerry, 1941- 12 1900 (has links)
Six sites within the Denton and Hickory Creek watersheds were sampled over three years to assess the impact of seasonal intermittent stream conditions on the ichthyofauna. An integrated approach using field and laboratory techniques was employed to evaluate the responses of the fishes.
59

Use of Automated Sampler to Characterize Urban Stormwater Runoff in Pecan Creek

Appel, Patrick L. 12 1900 (has links)
The purpose of this study was to use the Global Water Stormwater Sampler SS201 to characterize the urban runoff in Pecan Creek. Location of the samplers was influenced by land use and ease of installation. Determination of the constituents for analysis was modeled after those used in the NPDES permit for seven cities within the Dallas/Ft.Worth metroplex. Some metals, notably cadmium and arsenic, exceeded the U.S. EPA's MCL's. Statistical analysis revealed first flush samples to be significantly more concentrated than composite samples. Minimum discharge loadings were found to be significantly lower than maximum discharge loadings. Additionally there were significant differences of specific constituents between station locations and storm events.
60

An Assessment of the Riparian-influenced Salmonid Habitat Features of Johnson Creek, Portland, Oregon

Gude, Andrew Greiff 20 January 1994 (has links)
Pacific salmon populations in Johnson Creek, Portland, Oregon have been adversely impacted by urbanization, and by residential and agricultural land development. f Ecological impacts include loss or depletion of riparian vegetation features which directly influence stream and associated salmonid ecology. This research examines the nearstream riparian zone's contribution to instream habitat complexity for anadromous salmonids in Johnson Creek. Visual surveys were conducted on over half the stream length. Five features were assessed to determine the extent of riparian influenced stream habitat including, overhead enclosure, overhanging vegetation, undercut banks, and large and small woody debris and root wads. The stream survey showed that areas of riparian-influenced habitat are spatially intermittent and present in areas of the least stream disturbance. Suitable riparian habitat is limited to locations where there is minimal riparian disturbance, property management, and channelization. I Although salmonid populations have been reduced, insufficient riparian influenced salmonid habitat features are not the primary limiting factor on salmon populations. Other factors such as pollution, sedimentation, hatchery fish introduction, low flows, inadequate food supplies, high stream temperatures, repress wild salmon populations.

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