News Release, Kansas Geological Survey, June 28, 1996
Researchers James Butler, Geoffrey Bohling, and Carl McElwee from the Kansas Geological Survey, based at the University of Kansas, were recently awarded a $50,000 grant from the National Science Foundation to develop new, more accurate methods to predict the movement of contaminated groundwater.
Survey researchers plan to use miniature fiber-optic sensors to produce the geologic equivalent of a CAT-scan on underground rock formations. The sensors measure the permeability of rocks; permeability determines how fast fluids, such as water, move underground.
"The character of rock formations, and their permeability, differs drastically from place to place," said Butler. "Those differences control how fast contaminated water can move. By knowing how quickly a contaminant moves, we can more accurately assess the threat that a site poses to water users."
The researchers will install the fiber-optic sensors in uncontaminated, shallow wells at a study site northeast of Lawrence. The sensors, recently developed for biomedical use, will measure fluid pressure, an indication of the underground rock's permeability. Sensors currently used for such measurements are about the size of a cigar, and only one is installed per well. The fiber-optic sensors used in this project are the size of a pencil lead, which allows researchers to insert 18 per well.
"Today's methods may not detect the small, thin zones of permeable rock that allow water to move quickly at a site," said Butler. "That means we may under-estimate how fast a contaminant moves. This new technology should produce a better idea of where and how fast contaminants move, and help us design more effective schemes for cleaning up those sites."