Lifecycle assessment $($LCA$)$ is a systematic approach for evaluating the environmental impacts of products, processes, and systems over their entire lifecycle, from raw material extraction to disposal. Investigate the theoretical principles of LCA methodologies, including life cycle inventory analysis, impact assessment, and interpretation. How do engineers and designers apply theoretical models of LCA to quantify environmental impacts, identify hotspots, and inform decision$-$making processes related to product and system design, material selection, and process optimization in civil engineering projects?