Česká plynárenská a.s.

The ultimate speed underground gas storage - Rožná

Location

The underground gas storage facility is not located inside the former uranium mine. GSCeP is only using the uranium mine to access the migmatitic massif in which it the natural gas storage will then be located. The uranium mine in Rožná has been in operation for more than 50 years. In that period of time, it has excavated tens of kilometres of various tunnels, forming a virtual underground city made up of extensive labyrinths of interconnected passageways at a depth of up to 1200 metres. Uranium can be found in rock faults; therefore, when the exploratory boring hit the granite massif, the boring continued in a different direction and the massif remained intact. For its project, GSCeP needs to excavate the storage in this granite massif. If GSCeP wished to store natural gas in the mine tunnels, it would have to resolve the issue of uranium and radon contamination of the natural gas and would be at most able to attain the parameters of a seasonal storage.

Phases of construction

In July 2012, the ultimate speed storage in Rožná was in its pre-execution phase. Decisive information from explanatory work, which had been commenced in 2010, was available. In cooperation with the state enterprise DIAMO, which operates the uranium mine in Rožná, and a number of specialised facilities, such as VŠB – Technical University of Ostrava, GEAM and the Academy of Sciences, a great amount of information was compiled over a number of years and their evaluation is now being finalised. During exploratory work, almost one kilometre of exploratory tunnels were excavated and a number of bore holes carried out. A significant part of the excavated tunnels will end up becoming part of the storage. Based on an evaluation of the samples and measurements obtained and the numerous stress tests performed, GSCeP is now deciding on the specific placement of the storage in the localised migmatitic massif and is determining the future operating parameters of the storage. The migmatitic massif in which the natural gas storage project is to be located possesses such properties that it will allow maximum possible use of the most modern service technology available on the market today. Based on these results, it was decided that the optimum storage construction option would be used and negotiations on project financing were commenced. The second phase will see the construction of the storage itself in two adjacent caverns, one with a planned capacity of 100 million m3 of natural gas and the other of 80 million m3 of natural gas. Completion of the storage is planned for 2018.

More information at www.gscep.cz.