The Union of Concerned Scientists (UCS) has released an Infographic entitled "Safer Storage for Nuclear Waste," stating "Nuclear waste is piling up in our backyard—and it's not stored as safely as it could be."
While UCS refers to on-site dry cask storage as a "safer alternative" to densely-packed pools, Beyond Nuclear calls for safety upgrades to go one step further: HARDENED on-site dry cask storage. In fact, UCS itself has endorsed Hardened On-Site Storage (HOSS), as have hundreds of environmental groups representing all 50 states.
While HOSS may be the least bad interim measure for commercial irradiated nuclear fuel that already exists (some 70,000 metrc tons in the U.S.), Beyond Nuclear strives to permanently shutdown atomic reactors, to prevent the generation of any more radioactive waste. The only real safe, sound solution for high-level radioactive waste is to not generate it in the first place!