AIKEN, S.C. - Remote operations are crucial to worker safety in hazardous cleanup at the Savannah River Site (SRS).
Savannah River Remediation (SRR), EM’s liquid-waste contractor at SRS, relies on robotic technology to reduce hazards and improve operations in several liquid-waste facilities. Robots have cleaned debris in remote cells, retrieved samples in underground waste tanks, and repaired leaks to a vessel that evaporates wastewater.
They are essential to reducing the risk of radioactive waste to SRR workers, SRR President and Project Manager Tom Foster said.
“Robots provide an unmatched capability to work in radioactive environments that otherwise wouldn’t be possible," Foster said. “Using these devices to accomplish remote work means the workers’ exposure is reduced, keeping our people safe."
Cleaning DWPF Melt Cell
SRR asked EM’s Savannah River National Laboratory (SRNL) for robotic help to clean the Defense Waste Processing Facility (DWPF) melt cell. Radioactive debris remained after Melter 2 was removed for replacement in May. The melter produces a glassified waste safe for disposal.
SRR and SRNL chose a two-foot-tall robot used by law enforcement for bomb disposal and hostage situations. SRNL modified the device for remote deployment in the cell, attaching tools to gather and package the debris for disposal.
“SRNL's mission is to deliver advanced technologies that can accelerate Cold War legacy cleanup across the DOE complex," SRNL Director Terry A. Michalske said. “We are proud to support SRR's ability to use robotic technology to help keep workers safe and get the job done."
Tank Sampling
After workers remove waste from a tank to the extent practical, residual waste is sampled to determine regulatory compliance. Retrieving samples from the bottom of a one-million-gallon underground waste tank is a challenge. SRR modified a robotic crawler named G.I. Joe to better obtain waste samples than past robots used for sampling.
An engineer uses remote controls and cameras to maneuver the robot. G.I Joe grips a device for scooping the samples and places them in a retrieval basket, which is sent to the laboratory for analysis.
Repairing 3H Evaporator
A dynamic duo of robots helped fix leaks in one of two evaporators that reduce tank waste volume.
SRR and subcontractor AREVA attached a robotic arm to a robotic base and modified them to detect and repair leak sites in the 3H Evaporator vessel. The arm is widely used in the automotive industry and the base is used in demolition work.
The arm held tools to remove the lagging and insulation around the vessel, a camera for inspecting the leak sites, and an ultrasonic probe to measure the thickness of the vessel walls surrounding the leak sites. Two operators manipulated the robots remotely via real-time video.
“These robots were instrumental in identifying the leak sites on the evaporator," said Bill Barnes, the evaporator recovery manager. “Going forward they will continue to be instrumental in the repair methods."
The robots are commissioned to weld a cap to repair the leak site and prepare the evaporator for operations.
Source: U.S. Dept. of Energy, Office of Environmental Management
