The Environmental Impact Assessment Law of the People's Republic of China was passed on October 28, 2002, and officially implemented on September 1, 2003. The third chapter is about environmental impact assessment of construction projects. Article 25 stipulates: "If the environmental impact assessment documents of a construction project have not been examined by the examination and approval department as prescribed by law or have not been approved after the examination, the examination and approval department of the project shall not approve the construction, and the construction unit shall not start construction." Therefore, EIA, like safety assessment and occupational health assessment, is mandatory. Eia refers to the method and system to analyze, forecast and evaluate the possible environmental impact after the implementation of planning and construction projects, propose countermeasures and measures to prevent or mitigate adverse environmental impact, and carry out tracking and monitoring. Generally speaking, it is to analyze the possible impact on the environment after the project is completed and put into operation, and to propose countermeasures and measures to prevent pollution. All kinds of enterprises can conduct classified management according to the requirements of the EIA Classified Management Catalogue, and according to the degree of their products and environmental impact. Basically, it can adapt to all projects that may have a significant impact on the environment, identify and assess all possible significant impacts, generate environmental impact statements or report forms, and then submit to the environmental protection department for on-site assessment, and issue environmental assessment approval.