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In the past few years,many decommissioning activities have been carried out in China,but it was the first time to face NORM problems in the decommissioning of Shanghai Yuelong Chemical Plant.Yuelong in Chinese means flying dragon and used to be a rare earth plant.Actually,it used to be one of the most complete varieties of rare earth smelting and deep processing enterprises in China.It was built in 1960s,located near Yangzi River and covered an area of 160,000 m2.lnitially,a great deal of monazite was imported from abroad for rare earth production at the plant and serious environmental pollution was caused by backward production process and ineffective management.In 1990s,the plant abandoned the use of monazite and transformed the production facilities into the ones using ionic minerals without natural uranium or thorium.In 2003,the plant went bankrupt and became a legacy site.During production activities,about 10,000 1113 0f radioactive wastes,which contains 226Ra and 232Th,was left at the site and formed a potential threat to the surrounding environment.In order to eliminate the potential threat and to protect the environment,a decommissioning project was launched by the Ministry of Environmental Protection in 2009.Radiation measurements such as radiological source term survey,decommissioning monitoring and termination survey covered the entire decommissioning were implemented successfully in the end of April 2010.After the removal of radioactive materials and waste,the decontamination of facilities and the cleanup of sites,the plant site was released for unrestricted use.Due to NORM,special problems,which may differ from the ones occurred in other common nuclear and radiation facilities,were encountered during the decommissioning of Yuelong,such as lacking of operational level guidelines and technical standards currently,lacking of effective management and protection in the past as well as the disposal problems of NORM wastes.Through the study of this case,the contamination status of Yuelong is estimated based on the results of measurements.Comment is directed toward the special problems occurred at the legacy sites contaminated by NORM.These problems may not be encountered at any decommissioned facility or site,but they might be beneficial in most other decommissioning efforts.