Former Bergwerk Prosper-Haniel ventilation shaft site at Vossundern, Bottrop, whose headframe and surface buildings survive at the closed and backfilled Schacht 9 location.
Schacht 9 was the single shaft of the Schachtanlage Prosper IV, sunk from 20 August 1958 in the northern Kirchhellen-Grafenwald field of Bottrop using the freezing method. It reached a depth of 1,013 metres and entered operation in 1962 as a man-riding and ventilation shaft, opening coal production in the Flöz X seam. In 1974 the shaft was incorporated into the Verbundbergwerk Prosper-Haniel under the Ruhrkohle AG, within which it served as a ventilation and man-riding shaft throughout the mine's remaining operational life.
When Bergwerk Prosper-Haniel closed on 21 December 2018 — the last hard coal mine in Germany — Schacht 9 was among the five surviving surface access points. Preparatory work for backfilling the 1,013-metre shaft began in 2019, carried out by Thyssen Schachtbau. At the time of the preparatory works the headframe and associated buildings were still standing on the Vossundern site, with the administration and welfare building already vacated since 2016.
The origins of Schacht 9 lie in the northward migration of coal extraction at the Zeche Prosper during the 1950s. In the area of Kirchhellen, which was later merged with Bottrop in 1976, field ownership had been exchanged with the Gutehoffnungshütte, and in June 1958 a contract was concluded between Arenberg Bergbau AG and Neue Hoffnung for the driving of the Nordlicht cross-heading from Prosper II into the field Neu-Oberhausen toward Prosper IV. On 20 August 1958, in the midst of the coal crisis in German mining, the freezing works for Schacht 9 commenced at the Prosper IV site. The shaft was sunk to a final depth of 1,013 metres. In May 1960, coal extraction from the Prosper IV field began in the Flöz X seam. In 1962 Schacht 9 entered full service as a man-riding and ventilation shaft, a role it retained throughout its working life.
In 1974 the Ruhrkohle AG consolidated the Zechen Prosper, Jacobi, and Franz Haniel into the Verbundbergwerk Prosper-Haniel, within which the Schachtanlage Prosper IV was designated. The Schächte Prosper 9 and Prosper 10 and the Schächte Franz Haniel 1 and 2 formed the last group of active surface access points as the mine contracted. In March 2005 a conveyor fire occurred in the Prosper IV band-road system some kilometres from Schacht 9 at approximately 1,000 metres depth, leading to a reconfiguration of underground haulage and the installation of a new band-road on the seventh level in September 2005. Schacht 9 continued to serve its ventilation role and remained one of the five surface openings active when the mine was closed.
Bergwerk Prosper-Haniel produced its last coal in regular operation on 14 September 2018 and was formally closed in an official ceremony on 21 December 2018, attended by Federal President Frank-Walter Steinmeier, marking the end of hard coal mining in Germany and in western Europe. At closure, Schacht 9 was located at the street Vossundern in Bottrop-Grafenwald. By 2016 the training department and canteen had already been vacated, and the administration and welfare building stood empty. The last mine director, Thomas Telsemeyer, informed local residents of the forthcoming backfilling and the associated lorry traffic on 10 July 2019. From early August 2019, a lorry arrived every eleven minutes carrying sand from the Kirchheller Heide to serve as aggregate for the concrete backfill mix. The preparatory works were planned to conclude by the end of November 2019, with round-the-clock backfilling to follow. Thyssen Schachtbau had been engaged to carry out the backfilling of both Schächte 9 and 10 in parallel with the closure of the 3.6-kilometre Förderberg. Post-closure plans for the approximately 35-hectare Vossundern site provided for residential and commercial redevelopment of the land.