ABSTRACT
This introduction presents an overview of the key concepts discussed in the subsequent chapters in this part of this book. The part describes water quality management in the state of Nordrhein-Westfalen in the Federal Republic of Germany. The state of Nordrhein-Westfalen has long been Germany's center for coal production and the steel manufacturing and chemical industries. It contains 81% of Germany's coal mines, representing about 90% of the total coal production of the Federal Republic of Germany, and 72%, 31%, and 30% of the production capacities of the steel, petroleum refining, and chemical industries, respectively. At a population of 17.1 million, it is the most densely populated state in the Federal Republic of Germany. The industrial center of Nordrhein-Westfalen is the Ruhr area, the largest industrial agglomeration of Middle Europe. About 5.6 million people live in this area of 4600 square kilometers.
