Experiment on Random Field Using High Density Piezometer and Electrode Networks
In work supported by the Subsurface Science
Program at the U.S. Department of Energy, we looked at high density measurement
of head and chemical data. The flow cell shown had over 150 piezometers
installed. 136 of these were in a network designed to provide a spatially
distributed sample of gradients and water velocities. A ccd camera was also utilized to monitor the movement
of dye plumes as a second measure of pore water velocities.
Results from this work included:
-->Demonstration of our ability to measure the spatial statistics of pore
water velocities through visual and hydraulic measurements
-->Demonstration of our ability to measure the movement of a tracer plume
through use of an array of electrodes,
-->Characterization of the hydraulic response (in terms of the measured
hydraulic conductivity) in a heterogeneous porous medium and
-->Development of a new strategy for analysis of water level data
The piezometers were arranged in a modified scaled
pattern and consisted of 1/8 inch O.D. tubing installed through the wall of the
flow cell. Click on the image
below to review how the piezometer network was
created.
Publications Associated With This Work
Zheng. L. and S. Silliman,
“Estimating the theoretical semivariogram from
finite numbers of measurements”, Water Resources Research, 36(1),
361-367, 2000.
Conwell, P.M., S.E. Silliman,
and L. Zheng, “Design of a piezometer
network for estimation of the variogram of the
hydraulic gradient: The role of the instrument”, Water Resources
Research, 33(11), 2489-2494, 1997.