Legal basis: Article 3 of Decree No.20 of the Ministry of Environmental Protection of People's Republic of China (PRC), which states that the state practices qualification license for the operation of environmental pollution control facilities. Units engaged in the operation of environmental pollution control facilities shall apply for the operation qualification of environmental pollution control facilities in accordance with the provisions of these Measures, and engage in the operation activities of environmental pollution control facilities in accordance with the provisions of the qualification certificate.