A train pushes a container full of old equipment from H Canyon to the Solid Waste Management Facility for disposal at the Savannah River Site. The equipment is being removed to make way for a new H Canyon spent nuclear fuel dissolving campaign.
A train pushes a container full of old equipment from H Canyon to the Solid Waste Management Facility for disposal at the Savannah River Site. The equipment is being removed to make way for a new H Canyon spent nuclear fuel dissolving campaign.

AIKEN, S.C.EM contractor employees at the Savannah River Site (SRS) are preparing for an upcoming campaign to dissolve stainless-steel-clad spent nuclear fuel by installing a new dissolver and an additional double-sized tank for dissolved material storage.

Workers with Savannah River Nuclear Solutions (SRNS) are making room for the new equipment by disposing of old equipment at the H Canyon Chemical Separations Facility.

“The upcoming dissolving campaign will add a third electrolytic dissolver to the complement of equipment already in use in the canyon and will provide the capability to dissolve stainless-steel fuel,” SRNS Senior Vice President of Environmental Management Operations Wyatt Clark said. “The current chemical dissolvers are designed to dissolve aluminum-clad fuel, so they are not adequate to support the upcoming mission.”

A significant deactivation and removal campaign is underway to prepare for the mission. Crews at H Canyon recently finished removing the first of three shipments of legacy equipment to make room for this new campaign.

“When H Canyon equipment needs to be replaced, the old equipment is placed in a large, engineered container called a burial box, using the canyon remote cranes,” SRNS EM Operations Project Manager Richard Brown said. “Once that box is full, we secure the package, verify it is free of any radioactive contamination, and transfer it to the SRS Solid Waste Management Facility for disposal.”

To minimize the number of burial boxes required to remove old equipment, SRNS purchased a special cutting tool and a grapple system. These tools will be used to remotely reduce the size of large equipment to maximize the amount of equipment loaded into a burial box.

“We will be better protecting our workers through the use of this equipment since the material will be cut remotely instead of in person by employees,” said Brown. “While this equipment was specifically purchased for the upcoming dissolving campaign, we will be able to utilize it for future missions as well.”

Preparations for the new campaign also include preparing and calibrating the double-sized tank and new dissolver with the use of a bladder tank and pump system. The use of the bladder tank and pump system speeds up the calibration process by pumping water versus using a domestic water hose to fill the 50- and 150-gallon prover tanks, which are vessels used to add a specific volume of water to the tanks being calibrated. Once a calibration run is complete, the water is pumped from the vessel back to the bladder tank, using recycled water instead of fresh water for each of the four minimum calibration runs per vessel.

The stainless-steel-clad fuel is currently stored in SRS’s K Area and will be shipped to the canyon for processing. Once the fuel is dissolved in the electrolytic dissolver, the resulting solution will be transferred to the liquid waste tank farms. The material will then be transferred to the Defense Waste Processing Facility where it will be converted into a solid glass form and placed in an SRS facility for interim storage.

Spent nuclear fuel is nuclear fuel that has been irradiated in a nuclear reactor. The spent nuclear fuel from the site’s former production reactors, and from foreign and domestic research reactor programs, is safely stored in an underwater storage facility in L Area, called a disassembly basin.

Most spent nuclear fuel stored in L Basin is covered, or clad, in aluminum and then placed in aluminum bundles. However, a small portion of the fuel there is housed in aluminum bundles but clad in stainless steel or zirconium alloy, a type of metal known for its hardness and corrosion resistance.