Abstract: A method for the formation of a safe storage area to hold materials, where the storage area is in the form of an underground storage cavern in a preferably rock formation maintained at a different temperature from the natural temperature of the environs surrounding the walls, floor, and the ceiling of said storage cavern. The inside of the storage cavern is with or without insulation and an inner first circulation system surrounds the cavern. The circulation system has a plurality of channels regularly distributed around the cavern and near its surface parallel to the axis of the storage space. The system of tunnels formed of the channels together encloses and surrounds the cavern.

Abstract: In an underground storage, containing hot or cold storage materials, a circulating gas or fluid is passed in a plurality of conducts in the walls, floor, and ceiling of the storage and near their surface towards the storage, and, if a container or containing vessel is constructed inside the walls of said underground storage, the gas or the fluid is conducted either in the mentioned outer wall as previously mentioned or between the wall of the container and the outer rock walls, particularly in the last mentioned case also in ducts or in galleries with guiding devices for the medium to insure a corresponding contact with surfaces involved, or, in some cases, in the interior of said container wall.