The statement that canisters are only designed for 20 to 40 years is not correct. Canisters were initially licensed by the Nuclear Regulatory Commission for 20 years, since that was considered sufficient at that time; however, the canisters are designed to last for hundreds of years. Several years ago, this maximum licensing period was in fact changed from 20 to 40 years by the NRC. For the first 20 years of use, no monitoring or inspection programs are needed. After the initial licensing period, the vendor can apply for a license renewal for an additional 40 years which requires an adequate aging management program that includes inspections and maintenance.
