The tool which identifies and evaluates the environmental impacts of development projects, and proposes measures to mitigate negative impacts is the Environmental Impact Assessment (EIA). An EIA should be carried out for any project with potential significant negative impacts on the environment. In order to decide if a project requires an EIA or not an EIA Screening procedure is followed.

The purpose of the EIA is to assess the potential environmental impacts of a proposed project and its alternatives, in order to propose appropriate measures to mitigate negative environmental impacts and optimise positive effects, and assist the decision-making process.

EIA Screening - Screening refers to the decision to carry out the EIA, based on national legislation, the nature of the project and the sensitivity of the environment.

Stages of an EIA study

• Baseline study – It describes the initial state of the environment within the selected boundaries of the study area and a description of the “no project” scenario, based on assumptions regarding future changes.
• Identification and evaluation of environmental impacts. - The impacts are the differences between the situation with, and the situation without the project.
• Recommendations, mitigation/optimisation measures and the Environmental Management Plan (EMP). - Measures should be proposed to mitigate negative impacts (mitigation measures), as well as to optimise positive effects.
• The EIA recommendations must also provide an Environmental Management Plan (EMP), specifying the way the proposed measures should be implemented, and a monitoring plan.

Public participation – Participation of civil society, and particularly local communities and indigenous peoples, in this process is crucial in order to adequately integrate the experience and know-how of the populations living in the environment being studied, and to take into consideration the needs, values and interests of the populations concerned, including women and marginalised social groups. Public participation should be provided for from the earliest stages of the process.

Background documents
• Terms of reference EIA
• EIA Screening Guidance