The author uses the concept of evaluation as a guiding thread for the first time. The spread of chemicals is modeled to see where accumulations are conceivable. Chemicals in the environment and the environment in its states of burden are evaluated. For this purpose, dispersion models, methods for estimating substance properties (QSAR), effect models with an ecological background, and evaluation procedures are presented. The necessary mathematical apparatus is usually explained step by step. The book is suitable for anyone who wants to gain an overview of the broad areas of mathematical modeling of environmental chemicals, as well as for specialists dealing with evaluation procedures. The accompanying CD-ROM contains small programs that allow readers to be practically introduced to modeling and to develop specific focuses on modeling themselves.