Method | Wet mining |
Expansion of mud-flush drilling plants | < 160 m length / < 120 m width / <125 m height |
Number of currently active mud-flush drilling plants | 30 |
Daily mining progress in the mud-flush drilling plant | approx. 1 cm upward |
Usable mining height in the mud-flush drilling plant | 100 m |
Operating duration of a mud-flush drilling plant | approx. 30 years |
Brine yield per mud-flush drilling plant during the entire operating duration | approx. 1.300.000 m³ |
Brine yield of the Salt Mine per annum | approx. 900.000 m³ |
Daily freshwater requirement for the Salt Mine | approx. 2.000 m³ per day |
Expansions for the Berchtesgaden deposits
Open
From southwest to northeast | 4,5 km |
From northwest to southeast | 1,5 km |
Being mined
From southwest to northeast | 2,5 km |
From northwest to southeast | 1,5 km |
Proven deposit depth | 500 m bellow the valley floor |
Presumed deposit depth | 1.000 m below the valley floor |
Salt content in the mountain | approx. 50 % |
Tour
Visitors per year | approx. 350.000 |
Route length of the visitor mine train | 1.400 m |
Temperature below ground | +12 degree |
Length of the first slide | 34 m |
Length of the second slide | 40 m |
Duration of the tour (incl. putting on and taking off mine clothing) | appropx. 1,5 hrs. |
Terms
Wet mining
In Berchtesgaden, the salt is extracted using so-called "wet mining". This means the freshwater is fed into the mountain, which removes the salt from the composite rock. Brine is created, i.e. a concentrate salt solution with 26.5% salt content. This process continues in the same way today. The brine is extracted in the so-called mud-flush drilling plants.
Core drilling
Down to 400 m depth below the mining route level, samples are taken by drilling in order to ascertain the minimum salt content in the rock.
Mud-flush drilling plant
For extracting brine using wet mining, a hollow space is first developed. This is filled with freshwater. The water has the function of removing the water-soluble components from the mountain face, i.e. also the salt on ceilings and walls. The non-soluble components of the rock sink to the bottom and settle on the bottom. The hollow space is enlarged through constantly newly fed-in freshwater. This process is repeated until a 3,500 to 5,000 cubic metre so-called initial hollow space is completed.
Brine extraction
The continuous brine extraction begins when the ceiling area of the hollow space has reached approx. 3,000 m2. Approx. 1 cm of rock is removed from the ceiling space per day. With a mining height of 100 m, a mud-flush drilling plant can be used for approx. 30 years; during this time, we create more than 1.3 million cubic metres of saturated brine.
Brine
Saturated salt solution, i.e. salt water, contains the maximum possible proportion of 26.5% salt. In Berchtesgaden, brine is created by feeding the freshwater into the mountain and removing the salt from the rock there. The Berchtesgaden brine is pumped to the Salt Works Bad Reichenhall and further processed into industrial salts there.