Publication Date

2006

Document Type

Thesis

Committee Members

Allen Hunt (Advisor)

Degree Name

Master of Science (MS)

Abstract

In the late 20th century there was a spill of Technetium in eastern Washington State at the US Department of Energy Hanford site. Resulting contamination of water supplies would raise serious health issues for local residents. Therefore, the ability to predict how these contaminants move through the soil is of great interest. The main contribution to contaminant transport arises from being carried along by flowing water. An important control on the movement of the water through the medium is the hydraulic conductivity, K, which defines the ease of water flow for a given pressure difference (analogous to the electrical conductivity). The overall goal of research in this area is to develop a technique which accurately predicts the hydraulic conductivity as well as its distribution, both in the horizontal and the vertical directions, for media representative of the Hanford subsurface. The Hanford subsurface is a disordered sequence of ice-age flood deposits. It is known that concepts from percolation theory are well-suited to addressing transport problems in disordered media. The objective of this thesis was two-fold: (a) to implement techniques using critical path analysis from percolation theory for calculating the distribution of K values for soils with known characteristics, (b) to apply this technique to 53 sets of particle-size data and water retention characteristics taken from soils which represent the area in which the Technetium spill occurred. The research performed should be applicable to other contaminated sites under DOE supervision as well as being relevant for agriculture, climate models, mining and elsewhere.

Page Count

79

Department or Program

Department of Physics

Year Degree Awarded

2006


Included in

Physics Commons

Share

COinS