New Geocentrifuge Research Laboratory coming online

One-armed, short and powerfully built, the research advantage of the new geocentrifuge is its ability to shorten the time of experiments, thereby giving scientists their results faster. This is particularly significant to the INEEL's cleanup mission.

Acting like a "geologic time machine," the geocentrifuge subjects a test specimen to a high-gravity field by spinning it rapidly around a central shaft. In this high-gravity field, processes such as fluid flow occur much more rapidly. Using this technique, researchers can study in a few days or weeks the effects of tens of years of gravity-induced fluid movement. Spinning at full speed, the geocentrifuge is capable of more than 260 revolutions per minute and can apply as much as 130 times the force of earth's gravity on an experimental sample.

Bechtel BWXT Idaho, LLC President and General Manager Bill Shipp and Bechtel National, Inc. President Tom Hash opened the facility during a ceremony on Aug. 19 together with DOE-Idaho Chief Financial Officer Christine Ott.

INEEL researchers will use the geocentrifuge to study engineered caps and barriers designed to keep contamination from spreading, to develop more effective landfill designs, to improve our ability to characterize contaminated sites, and to study basic magmatic and tectonic processes.

The geocentrifuge has an asymmetric beam equipped with a pendulum swinging basket that rotates within a steel and concrete enclosure, which ensures both safety and aerodynamic efficiency during operation. A particularly significant feature of the geocentrifuge is an automatic balancing system. Because many environmental geocentrifuge applications involve fluid movement, this could lead to a change in the center of mass of the sample. The geocentrifuge will automatically compensate for such shifts during operation.

Bechtel National will be one of several entities utilizing the Geocentrifuge Research Laboratory. The laboratory will also serve as a user facility for outside scientists, so staff from other institutions and laboratories can perform research and training and test their scientific and engineering hypotheses. The facility will support both subsurface environmental and geotechnical engineering research.

Hash said, "The Geocentrifuge Research Laboratory will allow us to test various soil media and enhance our knowledge on how they will perform under different conditions. Also, our engineers will now be able to study geotechnical construction issues more effectively, such as alternative designs for earth retaining structures, dams and foundations."

INEEL has recruited two experts in the field of geocentrifuge research to run the new facility. Alan Stadler, Ph.D., will lead research, with the assistance of Hideo Nakajima, Ph.D., a postdoctoral fellow from the University of California, Davis. Stadler and Nakajima bring a wealth of technical experience and leadership, and view getting the word out about this new user facility as a priority. The two have already introduced the facility's emerging capabilities to the larger research community at an international geotechnical conference held in Canada this summer.

"A 2-meter geocentrifuge doesn't come online every day, or even every decade," said Stadler, who has conducted large scale centrifuge research at the University of Colorado at Boulder, and the University of North Carolina at Charlotte. "It's rare for a scientist to be given a blank slate like this. It's a once-in-a-career opportunity," he said.

Stadler and Nakajima bring a wealth of technical experience and leadership, and view getting the word out about this new user facility as a priority. The two have already introduced the facility's emerging capabilities to the larger research community at an international geotechnical conference held in Canada this summer.

Geocentrifuges are commonly used to study how geomaterials, such as soil and rock, respond when subjected to earthquakes, explosives, or the physical loads of buildings, roads, and bridges. INEEL researchers plan to leverage the strength of this research tool to address environmental cleanup issues.

INEEL staff will create idealized physical models of soil and rock to study real world problems. For example, they plan to investigate contaminant transport mechanisms within the vadose zone (the variably saturated zone of soil above the water table), the physics of fluid flow when the fluid itself it is different physical phases, and the transport of tiny particles called colloids.

Bechtel National paid for the centrifuge and its installation through a corporate funded research and development (CFRD) grant. The Bechtel National CFRD program is designed to expand the science and technology base at the INEEL. The Environmental Systems Research and Analysis program, sponsored by the DOE Office of Environmental Management, is funding staff and additional laboratory equipment.

The INEEL is a science-based, applied engineering national laboratory dedicated to supporting the U.S. Department of Energy's missions in environment, energy, science and national defense. The INEEL is operated for the DOE by Bechtel BWXT Idaho, LLC.

Technical contacts: Alan Stadler, (208) 526-4784, [email protected]; or Michael Wright, (208) 526-3315, [email protected] Media contacts: Deborah Hill (208) 526-4723, [email protected]; or Teri Ehresman, (208) 526-7785, [email protected]