Environmental Impact Identification and Assessment

Impact identification and assessment is a key step in the EIA process. The goal is to identify the potential impacts of a proposed development on the environment, predict the likely nature of those impacts, and evaluate the significance of those impacts. This information is then used to inform decision-makers about the potential consequences of the development and to identify mitigation measures that can be implemented to avoid, minimize, or offset negative impacts.

• Impact identification involves identifying the potential impacts of a proposed development on the receiving environment. This is an iterative process that begins during screening and continues throughout the EIA process. A variety of methods can be used for impact identification, including ad hoc approaches, checklists, matrices, networks, overlay maps, and modeling procedures. The choice of method will depend on the specific project, and multiple methods may be used.
• Impact assessment involves predicting the likely nature of the impacts and evaluating their significance. Impact prediction should be done at an appropriate spatial and temporal scale, considering both the magnitude of the impact and its likelihood of occurring.
• Impact significance is the value placed on the change by different affected parties. It is a value judgement that considers both the magnitude of the impact and the values of the stakeholders affected. Determining significance is essential to focus the EIA process on the impacts that matter most.

Determining Significance

There is no single definition of impact significance, and it can be difficult to determine objectively. However, various criteria can be used to assess significance, including:

• Technical criteria, such as environmental standards, objectives, or specific quantified criteria
• General sustainability criteria, often used when information is limited and scientific uncertainty exists
• Professional judgement of the EAP, which should consider the different value judgements expressed by stakeholders
• Nature, significance, and consequences of the impact, including the extent and duration, probability of occurrence, degree of reversibility, potential for irreplaceable resource loss, and mitigation potential

The specialist involved in the EIA process should consider the nature of the affected environment and communities when determining the potential impact significance. Their vulnerability and resilience to specific conditions must be considered.

Public Participation

Public participation is essential in determining significance. Input from interested and affected parties (I&APs) helps ensure that local knowledge and values are understood and considered when choosing between alternatives and in deciding the importance of issues. Engaging I&APs also helps identify project-specific criteria for assigning significance to potential impacts.

Specialist Studies

Specialist studies are often required to assess potential impacts on specific environmental or social components. The EAP is responsible for coordinating these studies, ensuring their findings are integrated into the overall impact assessment report. Specialists need to determine the amount of data required to supplement existing information to assess whether a significant impact will occur. They may need to undertake baseline surveys and descriptions of the affected environment.

Predicting Impacts

Impact prediction lies at the heart of EIA and requires an understanding of the relationships between various elements. Impact predictions should ideally be quantitative, but qualitative descriptions are acceptable when necessary.

Impact Assessment Methodology

The impact assessment methodology involves forecasting the change of environmental parameters due to development, including changes due to climate change. The most common methodology used for determining and ranking site sensitivities is a matrix selection process. This involves assessing the nature, significance, consequences, extent, duration, and probability of potential environmental impacts and risks.

Risk Ranking Outcomes

After identifying and assessing impacts, risks are evaluated and ranked based on their likelihood and consequences. Higher-risk events or issues, those with more significant consequences and likelihood, are prioritized for mitigation actions to lower their probability and/or reduce their consequences.

EIA Report

The findings of the impact assessment are presented in an EIA report, which should clearly and impartially document the impacts of the proposal, proposed mitigation measures, the significance of effects, and concerns of the public and communities affected by the proposal.

The EIA process is designed to improve decision-making on development projects by providing a framework for identifying, predicting, and evaluating potential impacts. It is a complex and iterative process involving various stakeholders, including the competent authority, applicant, EAP, specialists, and I&APs. The process aims to ensure that development projects are planned and implemented in a sustainable way, minimizing negative impacts and maximizing positive impacts.