Former kali mine ventilation shaft at Bernburg, sunk 1912–14, sealed in 1924 and today serving as an ausziehender Wetterschacht for the active Steinsalzbergwerk Bernburg.
Schacht Neuwerk II is the second of two outer Wetterschächte of the Steinsalzbergwerk Bernburg, located in the southern district of Bernburg known as Neuwerk. Both the Schacht Neuwerk I and Schacht Neuwerk II were sunk between November 1912 and 1914, each to 4.5 metres diameter with Tübbingausbau in the upper section; Schacht Neuwerk II reaches a final depth of 441.5 metres with Tübbingausbau to 138 metres. The shafts were sunk by the two Gewerkschaften, Bernburger Kaliwerke and Gröna, which the Kalifieber had inspired to begin construction of their own Schächte from 1912.
The associated Schachtanlage Neuwerk was closed in 1924 as part of the general Stilllegungsverordnung affecting the kali industry. Plugs were installed below the Tübbingsäule in Schächte Neuwerk I and II in 1924/25, but removed again in 1952/53 when the shafts were reactived as ausziehende Wetterschächte. Schacht Neuwerk II currently serves this ventilation function for the active Steinsalzbergwerk Bernburg, which is operated by K+S Minerals and Agriculture GmbH.
The Steinsalzbergwerk Bernburg owes its origins to the two Gewerkschaften Bernburger Kaliwerke and Gröna, both founded in November 1911, which were stimulated by the success of Kaliförderung in the neighbouring Staßfurt area and the general Kalifieber that followed. In 1912 both Gewerkschaften commenced sinking their principal shafts: the Gewerkschaft Bernburg began its Schacht Bernburg on 25 March 1912, and the Gewerkschaft Gröna its Schacht Gröna on 24 April 1912. As the operation expanded southward into the Neuwerk district of Bernburg, two further shafts were sunk between November 1912 and 1914 to serve the Neuwerk section of the growing Grubengebäude. These were the Schacht Neuwerk I, designated Coburg, and the Schacht Neuwerk II, designated Erbprinz and also known as Aderstedt (2). Both shafts share the same circular cross-section of 4.5 metres diameter as the other shafts of the complex. Schacht Neuwerk II reached a final depth of 441.5 metres; the upper 138 metres of its Schachtsäule were constructed with Tübbingausbau. For Schacht Neuwerk I the corresponding figures are a depth of 462 metres with 195 metres of Tübbingausbau.
The Kalisyndikat had permitted Kaliförderung at the Werk Bernburg from 1 August 1913; the First World War delayed regular Kaliproduktion until 1921. In 1924 the Schachtanlage Neuwerk was placed in Stilllegung as part of the Stilllegungsverordnung that swept through the German kali industry following the wartime disruption and postwar Kali crisis. Plugs were installed below the Tübbingsäule in both Schächte Neuwerk I and II in 1924/25 to prevent water ingress while the shafts remained nominally accessible from above.
With the gradual recovery of the kali and Steinsalz industry after the Second World War and the extension of underground workings into the Neuwerk field, these plugs were removed in 1952/53 and the shafts reactived to serve the growing ventilation requirements of the combined Bernburg–Gröna mine system. Schacht Neuwerk II has since served as an ausziehender Wetterschacht, drawing used ventilation air out of the mine. The active Steinsalzbergwerk Bernburg — of which Schacht Neuwerk II is now one of five shafts — is operated by K+S Minerals and Agriculture GmbH, a subsidiary of K+S AG. Since 1973 the Werk Bernburg has produced exclusively Steinsalz from the 115-metre-thick Leinesteinsalz, of which a 28-metre section is currently extracted. Since 1992 bergbaufremde Abfälle have been placed underground in exhausted chambers at a rate of approximately 140,000 tonnes annually.