Designing competitive production processes for the manufacturing of new chemicals requires meeting conflicting objectives such as economic performance, health and safety requirements and compliance with environmental regulations. While new conceptual processing schemes can be effectively generated through the BDK synthesis tools, Simulator_Evaluator and Process_Synthesizer, the ecological soundness of these candidates has to be assessed with respect to their overall performance in order to discriminate between promising candidates and inferior designs. The methodology of the Process_Assessor with its subsystems Material_Assessor and Treatment_Selector, supports evaluation of the quality for each of those designs in terms of their economic and ecological impact. Its features include impact assessment and compliance with regulations caused by all its process streams. The Treatment_Selector expert system suggest feasible treatment technologies for all waste streams and calculates the associated treatment costs. The final validation of the processing schemes includes cost estimates for the appropriate waste treatment strategy. The assessment of materials as well as consideration of the effort for waste treatment allows for identification of improvement potential for promising candidates and the elimination of inferior designs.