Steinsalzbergwerk Bernburg — Schacht Gröna Bernburg · Sachsen-Anhalt · Germany

The Gewerkschaft Gröna was one of two bergrechtliche Gewerkschaften founded in November 1911 in Bernburg, alongside the Gewerkschaft Bernburger Kaliwerke. Both were stimulated by the so-called Kalifieber, the wave of kali prospecting and shaft construction triggered by the lucrative operations in the neighbouring Staßfurt region. The Gewerkschaft Gröna began the Teufarbeiten for its Schacht Gröna on 24 April 1912, four weeks after the Gewerkschaft Bernburg had started its Schacht Bernburg on 25 March 1912. The Schacht Gröna was sunk to an original depth of 448 metres, later deepened to 529 metres, with a circular lichte Weite of 4.5 metres; the upper 175 metres of the Schachtsäule were fitted with Tübbingausbau. The Kalisyndikat issued the Beteiligungsziffer and permitted Kaliförderung at Schacht Gröna from 1 August 1913, at which point the shaft was already handling Ausrichtungssalze.

The First World War interrupted the establishment of the full production operation, and regular Kaliproduktion was taken up only in 1921. In 1921 Steinsalzgewinnung also began for the first time, with the initial chambers sunk near the Schacht Gröna. This first Steinsalzproduktion was small — only a few thousand tonnes annually — and was discontinued after four years. Between 1925 and 1942 only Hartsalz without fabrikatorische Verarbeitung was extracted through the combined operation. Steinsalzgewinnung restarted in 1939 and has continued without interruption since. In the period 1942 to 1954 no Kalisalz was extracted. During the Second World War the Salzbergwerk Gröna, which then belonged to the Wintershall-Gruppe, received selected archive materials from German Hansestädte — predominantly from Bremen, Lübeck, and Rostock — deposited underground for protection against bombing. These archival holdings were in 1945 first seized by the Monuments Men of the US Army and then transferred to the Red Army, whose Trophäenkommissionen conveyed them to the Soviet Union. Large portions were restituted in the 1990s in the context of the European détente.

After 1945 the Kaliwerk was nationalised and incorporated into the VEB Kaliwerk Bernburg-Gröna, which was later renamed VEB Kali- und Steinsalzbergwerk and assigned to the Kombinat Kali. From 1954 onwards Carnallitförderung was resumed through Schacht Gröna in particular, following the opening of the Carnallititfeld Aderstedt; this Carnallitproduktion continued until the commissioning of the Kaliwerk Zielitz in 1973. Since 1973 the Werk Bernburg has been an exclusively Steinsalz-producing operation, extracting from the 115-metre-thick Leinesteinsalz at approximately 500 metres depth; a 28-metre section within this is currently extracted. From 1968/69 a new Mahlanlage was erected for the Steinsalz operation. In 1993 the operation was privatised, initially as a joint venture between the Kali und Salz Beteiligungs AG and the Treuhandanstalt; in 2002 the Werk Bernburg was incorporated into the K+S subsidiary esco — european salt company GmbH & Co. KG, and currently operates as a Produktionsstandort of K+S Minerals and Agriculture GmbH, a wholly owned subsidiary of K+S AG. The approximately 80-metre Förderturm over Schacht Bernburg (the companion Hauptförderschacht) is visible from a considerable distance; the Schacht Gröna surface complex lies in immediate proximity. Since 1992 bergbaufremde Abfälle have been placed underground in exhausted Kammern. Annual Steinsalzproduktion from the combined Werk Bernburg exceeds 2.5 million tonnes. In 1965 the Gnetsch Solfeld was developed for the production of gesättigte Salzsole; the resulting underground Kavernen now house an Untergrundspeicher for Erd- and Flüssiggas administered by VNG Gasspeicher GmbH with a capacity of 1.0 Milliard cubic metres, and two Flüssiggaskavernen operated by the Salzwerk.