Groundwater dynamics in degrading, discontinuous permafrost
dc.contributor.author | Barnes, Michelle L. | |
dc.date.accessioned | 2015-02-02T23:33:43Z | |
dc.date.available | 2015-02-02T23:33:43Z | |
dc.date.issued | 2014-12 | |
dc.identifier.uri | http://hdl.handle.net/11122/4896 | |
dc.description | Thesis (M.S.) University of Alaska Fairbanks, 2014 | en_US |
dc.description.abstract | In regions impacted by permafrost, discontinuities are areas of possible connection between the supra- and sub-permafrost portions of an aquifer. Permafrost discontinuities influence the transport of contaminants in an aquifer, necessitating delineation of these discontinuities and their influence on groundwater flow. Means of identifying the locations of permafrost discontinuities have previously been limited to geophysical methods and the evaluation of well logs. In this study we use groundwater elevation trends and environmental tracers (e.g., stable isotopes and temperature) to evaluate the dynamics in a sulfolane-contaminated aquifer located in a region of discontinuous permafrost in the Interior of Alaska. Using tracers to identify areas of discontinuities in the permafrost should help us locate thawed through-taliks and may also improve our understanding of the interaction between the supra- and sub-permafrost groundwater in discontinuous permafrost. With this approach we identified at least three discontinuities within the study area. The locations of these discontinuities coincide with transport of the contaminant found in this aquifer. The primary source of recharge for this aquifer is the Tanana River, a major tributary to the Yukon River. The source of water for the Tanana River is glacial melt in the summer and groundwater during the winter. Through the isotopic composition of the supra-permafrost groundwater we show the occurrence of additional recharge to the supra-permafrost groundwater from sub-permafrost groundwater and precipitation. Understanding these dynamics is paramount to characterizing the contaminant transport in permafrost impacted aquifers. | en_US |
dc.description.tableofcontents | 1 Introduction -- 1.1 Thesis Objectives -- 2 Site Description -- 2.1.1 Sulfolane Contamination -- 2.1.1.1 Contaminant Characteristics -- 2.1.1.2 Groundwater Contamination -- 2.1.2 Climate, Land Use and Land Cover -- 2.1.3 Geology and Permafrost -- 2.1.4 Hydrology -- 2.1.4.1 Aquifer Recharge and Properties -- 2.1.4.2 Tanana River -- 2.1.4.3 Chena River -- 2.1.4.4 Moose Creek Dam -- 2.1.4.5 Sloughs -- 2.1.4.6 C-ditch and Gravel Pits -- 3 Natural Tracers and Trends in Groundwater Elevations -- 3.1 Groundwater Elevations -- 3.2 Groundwater Temperatures -- 3.3 Stable Isotopes -- 4 Methods -- 4.1 Data Collection -- 4.1.1 Groundwater Elevations -- 4.1.2 Groundwater Temperatures -- 4.1.3 Stable Isotopes -- 4.2 Data Analysis Procedure -- 4.2.1 Groundwater Elevation Trends -- 4.2.2 Groundwater Temperature Profile Trends -- 4.2.3 Stable Isotope Classifications -- 5 Results -- 5.1 Groundwater Elevation Trends -- 5.2 Groundwater Temperature Profile Trends -- 5.3 Stable Isotope Classifications and Trends -- 5.3.1 Monitoring well -- 5.3.2 Private Sub-permafrost Wells -- 5.4 Combined Spatial Analysis -- 6 Discussion -- 6.1 Indicators of Discontinuities -- 6.2 Locations of Discontinuities -- 6.3 Ground Penetrating Radar -- 6.4 Differences in Isotopic Signatures -- 6.5 Improved Understanding of Aquifer Dynamics -- 6.5.1 Spring 2013 -- 6.5.2 Late Summer 2013 -- 6.5.3 Fall 2013 -- 6.5.4 Supra-permafrost Groundwater Recharge -- 6.6 Contaminant Transport -- 6.7 Other Applications -- 6.8 Groundwater Temperature Profiles Used for Indicators of Taliks -- 6.9 Future Work -- 7 Conclusion -- References -- Appendix. | en_US |
dc.language.iso | en_US | en_US |
dc.title | Groundwater dynamics in degrading, discontinuous permafrost | en_US |
dc.type | Thesis | en_US |
dc.type.degree | ms | en_US |
dc.identifier.department | Department of Civil and Environmental Engineering | en_US |
dc.contributor.chair | Barnes, David L. | |
dc.contributor.committee | Shur, Yuri L. | |
dc.contributor.committee | Schnabel, William E. | |
dc.contributor.committee | Leigh, Mary Beth | |
refterms.dateFOA | 2020-03-05T09:15:01Z |