Policy risk. Changchun Huijin wastewater treatment plant ppp project in February 2003, the government repealed the "franchise approach" on the grounds that the document violated the provisions of the State Council on fixed returns, this policy change is equivalent to destroying the operational basis of the project, the drainage company ceased to pay the Changchun Huijin company from March 2003, so that the cumulative loss of the Huijin company amounted to RMB 97 million yuan, which is an obvious cause of the policy change that led to the buyback of the project.