Basic Concepts for EIA

• Environmental impact assessment is a formal process for identifying likely effects of activities or projects on the environment
• Environmental impact assessment identifies impacts on the environment, human health, and human welfare
• Environmental impact assessment is a means and measures to mitigate and monitor these impacts
• There is always a positive and negative impact in every progress and development
• Environment is broadly interpreted as physical, biological, and social aspects
• Impact


  A deviation or change from a baseline situation that is caused by an activity
• Baseline situation is the existing environmental situation or conditions in the absence of the activity
• Environmental components in the baseline situation

  • Water (quantity, quality, reliability, accessibility)
  • Soil (erosion, crop productivity, fallow periods, salinity, nutrient concentrations)
  • Fauna (populations, habitats)
  • Environmental health (disease vectors, pathogens)
  • Flora (composition, density, productivity, key species)
  • Ecosystems (key species)
• Baseline situation describes both the normal variability of environmental components and the current trends
• Types of impacts

  • Direct
  • Indirect
  • Short-term
  • Long-term
  • Adverse
  • Beneficial
  • Cumulative
• Impacts are described by attributes like intensity, direction, spatial extent, duration, frequency, reversibility, and probability
• Not all impacts are treated equally, the most significant impacts are focused on in the EIA process
• Activity


  A desired accomplishment or output that requires a set of actions
• A project or program may consist of many activities