Nuclear wasteStudying Spent-Fuel Canister to Support Long-Term Storage

Published 18 August 2021

Nuclear waste is stored in more than sixty dry-cask storage sites in thirty-four states. These facilities store the majority of the more than 90,000 metric tons of nuclear waste in the United States, including nearly 80,000 tons of spent nuclear fuel.

The receipt of a nuclear fuel canister is boosting the research of an Oak Ridge National Laboratory team investigating methods to help the nation effectively dispose of nuclear waste for the long term.

“The high-level radioactive waste generated from a nuclear power reactor to supply a person’s electricity needs over a 100-year lifetime would be about the size of 100 sheets of paper,” said Rose Montgomery, leader of ORNL’s Used Fuel and Nuclear Material Disposition group. “My team’s goal is to help the U.S. Department of Energy in its mission to reduce that volume even further and to figure out long-term solutions for storing, handling and disposing of the nation’s nuclear fuel currently being held in interim storage.”

The canister, originally slated for use by the San Onofre Nuclear Generating Station in California but never used to store spent fuel, stands over 16 feet tall and weighs about 22 tons empty – roughly the equivalent of five small pickup trucks. ORNL is one of three national labs selected to receive canisters from the U.S. Department of Energy for ongoing nuclear storage research projects. 

The canisters play an essential role in the nuclear power industry, which is a major component of the nation’s carbon-free electricity production.

“The nuclear energy industry is unique among power generation options in that its used fuel is inertly stored in sealed canisters that are robustly designed as required by the stringent requirements of the Nuclear Regulatory Commission, the Department of Energy, and the Environmental Protection Agency,” Montgomery said. “The used fuel is tracked and traceable, and it can be retrieved at any time for reprocessing and reuse.”

At a nuclear power plant, fuel rods containing uranium are used to generate electricity. At the end of their power production cycles, the fuel rods – which are hot in regard both to temperature and radioactivity – are stored under water in specially designed pools to cool for about five years. Then, while still under water, the rods are transferred into large storage canisters. When a canister is moved to dry storage, water in the canister is removed by drawing it out through a long, narrow pipe inside of the canister.