Drilling at Germany's deepest workplace

It takes a good half hour to reach District 6 south in the east field of the Zielitz mine by road vehicle. Passing through several ventilation locks, the journey descends slowly but steadily for about six kilometers. While the temperature in the open-topped jeeps is still comfortable at the beginning of the trip, it gets warmer by the minute. Even the wind soon fails to cool us down. The air on the route becomes increasingly dusty, and there is a very pleasant smell of salt. When we get off the car at our destination at a depth of almost 1,400 meters, we are already dripping with sweat. This is Steffen Quaas' workplace. The 44-year-old miner has been working at the Zielitz potash plant since 1999. His brother Heiko also works here, just as their father used to.

"I prefer working in a place where I sweat and don't freeze," Quaas answers when asked about the special climatic conditions at his workplace, which is currently the deepest one in Germany. Today he is wearing a black T-shirt without sleeves and, as always, short work pants. Some sweat has formed on his face and on his arms and legs. His shift here is shorter than the usual eight hours in other districts because of longer breaks. Due to the special conditions, however, he and his approximately 50 colleagues in District 6 receive a so-called climate bonus with more vacation days. Quaas must drink up to six liters of water and juice per shift to compensate for the loss of body fluids. Refrigeration cabins provide short-term respite. These are containers with built-in air conditioning where the miners can have breakfast, for instance. 

Due to the great depth, the working face is very hot here, so you can put your hand on it for a few seconds at most. There is also a clearly audible cracking and crackling sound in the rock every few minutes. "This is due to the high rock pressure down here, which always releases, but it is completely harmless," explains District Manager Patrick Schäfer. Miners are only allowed to work underground up to a maximum wet-bulb temperature of 27 degrees. The wet bulb temperature is the temperature that occurs because of evaporation on a moist surface. If the air above the surface is saturated with water vapor (humid air), no evaporation takes place, and the wet bulb temperature is equal to the air temperature. If this is exceeded, production must be interrupted, according to the regulations of the employers' liability insurance association. Otherwise, the human body can no longer sweat, which would have negative health consequences.

Quaas is a drilling specialist and mainly operates the blast hole, anchor, and large hole drill rigs in District 6. "In underground drilling technology, you have to be very proactive and need a lot of experience," says Quaas, who continues to enjoy his job at the mine.

Not too much has changed in the more than twenty years he has been working down here, says Quaas. "In the meantime, more computer-aided technology supports us in the extraction, for example in the operation of the vehicles, but most things still have to be done manually through a lot of experience." It continues to be important, he says, that "you can rely on everyone down here. "In the mine, we are all buddies and stick together!" 

Quaas is married and the father of four children, including triplets. His father had once worked in Merkers and then relocated to Zielitz when the plant started up in the 1970s. The job as a miner was therefore already laid in the cradle for him and his brother. In his free time, Quaas likes to read and do sports. "I also prefer to go on vacation in the warm, because otherwise I get cold quickly."