Fermi 2 moved used fuel from its used fuel pool into storage canisters for the first time in 2014. The canister storage method, used at nuclear power plants since the mid-1980s, involves putting used fuel inside canisters with reinforced steel and concrete two-feet thick. The canisters are welded shut and backfilled with helium.
The canisters, which each weigh about 100 tons, sit on a highly-engineered concrete pad, where they are controlled, monitored and safeguarded inside the site’s protected area. Each canister contains 68 fuel bundles. The canisters are 20 feet tall and 11 feet in diameter. Standing right next to a canister for one hour would result in 0.1 mrem in dose exposure – or less. For perspective, a medical X-ray is 10 mrem.
Canisters can withstand natural disasters such as earthquakes and tornadoes, and also terrorist attacks. They are extremely safe and reliable and provide both structural strength and radiation shielding.
The general license granted to Fermi 2 by the NRC allows us to store used fuel on site in the canisters. The NRC approves and observes all aspects of the program. Fermi 2 only implemented this initiative after successfully demonstrating to the NRC that it complied with all requirements and is proficient in the use of equipment and the steps needed to perform loading of canisters.