The Ostrava-Karvina District as the most significant deposit of black coal in the Czech Republic has always played a strategic role in the industrialization of the Ostrava Region and other parts of the republic. The mass and volume of coal, rocks, water and gas (methane in particular) extracted in the Czech part of the basin since the beginning of the industrial coal mining can be given in general terms only. It is estimated though that in the period from 1872 to 2000 about 1.6 billion tons of coal were extracted in the Ostrava-Karvina District. The production of waste rock can be estimated at 0.65 billion tons and the total production of coal slurries at 40 million tons. Preferred investments into the provision of coal mining began to be gradually reflected in the coal preparation plants being behind the times. The pace could be maintained only by using the coarse part of the production; the fine coal production has been sub-standard ever since, which was reflected in the growth in slurries and waste water production from the coal preparation plants.