Will the encased spent fuel be as safe as dry casks?

Yes. The U.S. National Academy of Sciences concluded that the ultimate disposal of spent nuclear fuel should be done deep underground in stable geologic formations. Dry casks offer an “engineered barrier.” We consider dry cask storage to be safe for interim timeframes, but nobody claims it is safe for longer term disposal (hundreds to thousands of years and longer). For long-term disposal, many people have argued that a combination of an engineered barrier and a geologic barrier offers redundancy against the unexpected. Deep Isolation offers this redundant combination.