Physical Sciences and Mathematics Commons^™

Rare Earth Element Transport In The Yucca Mountain Region, Liqiong Zhang

UNLV Theses, Dissertations, Professional Papers, and Capstones

In sync with environmental pollution of solutes in nature, from source, process to consequence, geochemical processes (leaching and sorption) and hydraulic transportation of the rare earth elements (REEs) have been investigated at Yucca Mountain (YM), Nevada. This research includes the leaching behavior of trace elements (including REEs) from aquifer rocks, the surface complexation reactions of REEs in synthetic groundwater, and transportation of reactive REEs in the local-scale groundwater system of YM. This dissertation includes three projects. These studies indicate that surface complexation reactions may retard the transportation of REEs along groundwater paths in YM, which suggests a similar behavior of …

Uncertainty In Recharge From Subsidence Craters At Frenchman Flat, Nevada Test Site: Impacts Of Initial And Boundary Conditions And Media Properties, David Matthew Ely

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Nevada Test Site has over 400 subsidence craters formed by the collapse of overlying rock following underground nuclear tests. Under natural conditions, infiltration and recharge would not be considered likely due to infrequent precipitation events and extreme evapotranspiration. Crater U5a in Frenchman Flat was chosen for study because it intercepts significantly more drainage than surrounding craters. Vadose zone modeling was conducted to test the sensitivity of water movement to boundary and initial conditions. The effects of ponding depth was negligible but depth of wetting front movement was highly dependent on the lateral extent of the ponds. The model was …

Ground Water Flow Systems Of Central Nevada, G. William Fiero Jr

UNLV Theses, Dissertations, Professional Papers, and Capstones

The U.S. Atomic Energy Commission has been evaluating a large area of central Nevada in order to define a supplemental test site for the underground testing of high-yield nuclear devices. Safety considerations involving the radiocontamination of the ground water in the vicinity of the test site necessitated that research be conducted to determine the direction and rate of flow of the ground water. This investigation defines the ground water flow systems in eighteen valleys comprising 12,000 square miles of central Nevada.

The definition of the systems was made following a compilation of existing hydrologic and geologic data for the area. …