Dismantling of campus nuclear reactor under way
INSIDE ILLINOIS, Dec. 1, 2011 | Susan Mumm, Nuclear, Plasma and Radiological Engineering
A chapter in the history of the department of nuclear, plasma and radiological engineering is coming to an end with the dismantling of the UI Advanced Teaching Research Isotope General Atomic reactor and demolition of the Nuclear Reactor Building.
The main components of the reactor core were dismantled with the fuel removal in 2004. The upcoming work will involve removing the fuel support structure and then the concrete bioshield.
“First they will come in and remove the loose stuff,” said Rich Holm, reactor administrator. “Then they will build a gantry crane inside the building to remove the concrete.” In addition to the new crane that will run from the northeast to the southwest over the top of the reactor, crews will use the existing crane that runs north and south.
A shield 16 feet deep surrounds what was the reactor core, and a 7-foot radial concrete sheath weighing more than 1 million pounds surrounds the reactor’s water core. After crews remove the remaining reactor core assembly, they will use a diamond-abraded cable wire-saw to cut into the concrete.
“We did a survey all over the building and drilled into the concrete bioshield to create a map showing where the radioactivity was and where it was not,” Holm said.
The building and its walls are not radioactive, while some radioactivity exists in the building’s floor. Although the reactor pool still holds water, there is no radioactive liquid in the building.
Crews will separate the non-contaminated concrete from that which is radioactive. The radioactive material, estimated at 100 cubic meters, will be shipped to a waste facility in Utah. “The cost of the radioactive disposal is a quarter of the cost of the entire project,” Holm said.
Workers will encase the cutting operation with plastic shields, reducing any chance of the spread of radioactive contamination. Students and others will be allowed to observe. “We’ll have access to classes,” Holm said. “With prior notification, it’s OK to view this, and it’s educational. We will make it as much of a learning opportunity as possible.”
“The final status will be a hole in the ground,” Holm said. “There’s been no specific decision as to what to do with the site once the building is down.”
The TRIGA reactor went critical Aug. 16, 1960. The university dedicated its Nuclear Reactor Laboratory on Oct. 21 that same year. The reactor was used primarily for the training of students in nuclear engineering, but also as an interdisciplinary facility, with the departments of chemistry and chemical engineering, physiology and biophysics, physics and other engineering departments using it.
In 1968, the university approved upgrading the reactor and increasing its steady peak power. The UI, the National Science Foundation and the Atomic Energy Commission funded the $1.4 million upgrade adding 12,160 square feet to the reactor.
The reactor operated for 38 years before it was shut down in 1998.
The reactor facility was vital in the graduate theses of about 600 NPRE graduate students, and was a teaching tool for many of the department’s undergraduates said Holm, who became a senior active reactor operator while earning his NPRE master’s degree in 1990.
Holm said the UI Reactor Safety Committee reviewed all work procedures and quality assurance requirements in the removal of the building and remediation of all radioactive components.
UI personnel will monitor the demolition process, including a radiation safety officer from the campus Division of Research Safety. The project also will be overseen by the Illinois Emergency Management Agency and the Nuclear Regulatory Commission.
The $4 million project is scheduled for completion by summer 2012.