The sound of a pneumatic pump used to spray liquid concrete. Manufactured by the Meyco Machine and Tool Inc., California, USA, in 1998. This method of pumping concrete is known as ‘shotcrete’. The mine structures with a lifetime of more than 10 years are supported by steel ribs, welded wire mesh and up to 20 to 30cm of shotcrete. The dry concrete mix is placed into a hopper, water is added and the mixture is conveyed through a hose and pneumatically projected onto the welded wire mesh.
The sound was recorded in the Trbovlje-Hrastnik coal mine which has a long tradition. The first mine in the Trbovlje area, founded by the entrepreneur Franz Maurer from Wiener Neustadt, Austria, started to operate in 1804. It was later followed by several smaller mines. The arrival of the Austrian Southern Railway to the Zasavje region in 1849 was a double gain: it facilitated the transport of coal to clients whilst simultaneously the railway itself was a major customer itself, having a great need for coal. In 1873 all the coal mines in Zasavje were merged under Trboveljska Premogokopna Družba (Trbovlje Coal Mining Company) which remained the proprietor until WWII. After 1946 all coal mines were nationalised by the new socialist authorities. Zasavje coal mines reached their peak of production and technological development in the second half of the 20th century. After 1991 coal was no longer considered the energy source of the future, and so the state decided to gradually close the mine. The extraction of coal ceased in 2010 and the company focused exclusively on closing it down which should be completed by 2018.
Sound recordist: Boštjan Troha
Video Recordist: Irena Marušič
Photographer: Neža Renko