Identification and classification of key variables and their role in environmental impact assessment: methodology and...

There is, as yet, no proven methodology to enable, objectively, the identification of key parameters out of a large number one normally encounters during any EIA. As EIA is a costly and time-consuming exercise, it is necessary to separate the man from the boys--so to speak--in order to optimize costs and efforts. In this paper a methodology for distinguishing the more important parameters from the less important ones, developed by us, is described. The methodology aims at identifying and shortlisting the key parameters which ought to be studied in a given EIA situation, thereby helping in reducing time, effort, and cost of EIA. With this methodology a system structure is developed which gives hierarchical pattern of inter-parameter interaction, and reveals several distinguishing features of each parameter. A software package INTRA (INTer-parameter Relationship Analysis) based on this methodology, has been developed. The paper also describes a case study in which INTRA has been used to study the environmental impacts of urbanization of a typical third world town (Roorkee).