October 8, 2007
6:00 - 7:30 pm
State Technical Community College
10915 Hardin Valley Road, Knoxville
Lamar Alexander Building, Room 223
Hydraulic Properties of the Vadose Zone
at the Department of Energy Site in Hanford, Washington
Elmer van den Berg
and Ed Perfect
University of Tennessee
Dept of Earth & Planetary Sciences
This talk presents a general background to centrifugation and the range of applications of this technique in the earth sciences. A case study is presented on hydraulic property determinations using centrifugation of samples from the vadose zone at the Department of Energy site in Hanford, Washington.
Centrifuges have been used for several decades to measure the hydraulic properties of porous media. The advantages of this method are: 1) the centripetal acceleration, which is many times greater than Earth&rsquos gravitational acceleration, speeds up the fluid flow experiments significantly; 2) because of increased acceleration, hydraulic properties can be measured over a wide range of saturation within a single experiment; and 3) like gravity, centripetal force is a body force acting on all components equally. Recently the University of Tennessee acquired a URC-628 ultra rock core centrifuge for performing transient-state flow centrifuge experiments. This equipment is widely used in petroleum reservoir engineering but has seen only limited usage in environmental sciences. Our goal is to investigate the potential of the transient flow centrifuge technique in environmental applications. After significant testing of the instrument and developing analytical and numerical simulation tools to interpret the results, we are now using the URC-628 to measure the hydraulic properties of sediment samples taken in the Hanford site vadose zone.
Page updated October 8, 2007