As underground storage facilities keep the stored product deep under the surface of the earth and can, as a rule, only be accessed by drilling, the stored medium is very well protected against the forces of nature, damage and even violent attack.
In cases where accidents occur on the surface, the sub-surface part is safely sealed off from the rest of the facility by mean of automatically closing shut-off valves. The risk that fire could encroach on the subsurface part of the storage facility, or that it could explode is virtually impossible as there is no influx of oxygen.
In the planning, construction and management of the surface equipment, all aspects conerning the safety are systematically taken into account. These are also part of the operation plans submitted to the mining and exploration authorities and are taken into account in both special technical solutions (surveillance and warning systems, fire extinguishing systems, installation of rapidly closing valves etc.) and in planned measures for preventing and controlling damages. Any remaining risks are assessed in terms of any repercussions - and suitable countermeasures for minimising risks are defined.