NWKG –
Rüstringen, Heide, Sottorf and Lesum:

Cavern site in Ruestringen
Aerial view of the cavern site

Cavern storage for the natural oil reserve

NWKG mbH, a wholly-owned subsidiary of the Petroleum Stockholding Association, runs four underground storage facilities with together 59 caverns: Rüstringen, Heide, Sottorf and Lesum. These caverns are part of the national crude oil reserve, a precaution for possible times of crisis. KBB UT provides support for all solution mining activities of these caverns and gives also advice regarding rock mechanical and geological solutions.

The largest underground storage facilities are located in Rüstringen. In 1968, drilling operations started at the Rüstringen salt dome and 35 salt caverns were leached as part of the national crude oil reserve. 9 million m3 of crude oil are stored in these caverns. To maintain the existing storage volume, a re-leaching project was started in 1998. The former KBB and later KBB UT provided support for the project, especially all engineering services, planning and supervision activities for solution mining of the caverns as well as the continuous supervision during operation and all corresponding laboratory analysis.

In 2008, six new wells were drilled to expand the cavern capacity. KBB UT has been supervising the activities of five caverns regarding all aspects of solution mining. The first of the five caverns was already completed and ready for operation in 2015.

NWKG plans the successive completion of the other four caverns to expand the national crude oil reserve even more.