This paper aims to investigate and compare the Environmental Impact Assessment (EIA) practices at both international and national levels, specifically emphasizing the Indian context. EIA is a crucial tool for sustainable development, and understanding the variations and similarities in environmental impact frameworks globally can contribute to the improvement of environmental governance. The study will explore the evolution of EIA, key principles, methodologies, and legal frameworks at the international level, and then delve into how these principles are implemented and adapted at the national level in Indian scenarios. The research will adopt a comprehensive approach, utilizing a combination of literature review, cases filed in courts, comparative analysis, and interviews with people living in the Bhopal gas accident site taken in person. The study discussed air pollution modelling in the last part, which is the only solution for impact assessment for gaseous release as per EIA 2020—within the gaseous release locations and scales of governance had been discussed based on satellite data and urban local bodies for future development plans. Overall, the study acts as the position of the Indian subcontinent in the world context on environmental sustainability and industrial planning approach.