Disclosed are the apparatus and methods for closing a canister that stores and transports spent nuclear fuel. In one embodiment, the canister includes a canister shell that includes an open end. A closure lid is inserted within the open end of the canister shell. The closure lid engages the open end of the canister shell to provide a weld area that is substantially on the outer circumference of the closure lid. The weld area includes a first weld layer and a second weld layer. The first weld layer welds the closure lid to the canister shell at the weld area and closes the canister. The second weld layer also welds the closure lid to the canister shell at the weld area, providing a redundant closure seal, and is disposed substantially on top of the first weld layer. The method for closing the canister is provided herein.