In order to reducethe influence of wastewater from enterprises on the environment extreme relevance is gained by improvement of the monitoring system at each stage of technological process. A new tool - calculation of the polluting substances concentration is suggested to be entered into the monitoring system on the basis of determination of material balance of the technological process of production that will allow prediction of qualitative and quantitative composition of sewage for the selected period. The system can be used in any enterprise, but the example with all calculations is given for the Mykolaiv Branch of \\\"SUN InBev Ukraine\\\" which became the object of research. The scope of the study covered the process of wastewater formation of the enterprise. Realization of tasks demanded the use of general scientific methods: analysis, synthesis, systematization and generalization in the course of studying of the corresponding literature on the research subject; modeling, formalization, comparison - at drawing up the calculation scheme of concentration of the polluting substances in sewage; supervision - during studying the technological scheme of production; and also methods of mathematical data processing in MS Excel.