Investigate the principles of environmental impact assessment $($EIA$)$ and sustainability appraisal in civil engineering projects. Discuss the importance of assessing the environmental, social, and economic impacts of infrastructure development projects. Explore EIA methodologies such as screening, scoping, and impact prediction, and discuss their role in identifying potential environmental risks and mitigating measures. Analyze sustainability appraisal techniques such as life cycle assessment $($LCA$)$ and cost$-$benefit analysis $($CBA$),$ and discuss their role in optimizing infrastructure design and decision$-$making.