The sound of a submersible pump in operation in a coalmine. It is a Bibi 3 model pump manufactured by Flyft, USA, in 1993. This 3kW pump with a capacity of 600 l/min is used for controlling minor water inflows. Larger inflows (over 1 m3/min) are served by the pumping stations that house several more powerful pumps, and consequently can handle a greater inflow of water.
Water flows into a number of mine structures. It could be surface water from precipitation or water percolating through the rock surrounding the mine structures. Systems for removing this water in a mine comprise of a network of pumps that raise water to a level where it can drain off.
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: Dušan Oblak
Photographer: Neža Renko