[ASME ASME 2013 15th International Conference on Environmental Remediation and Radioactive Waste Management - Brussels, Belgium (Sunday 8 September 2013)] Volume 2: Facility Decontamination and Decommissioning; Environmental Remediation; Environmental Management/Public Involvement/Crosscutting Issues/Global Partnering - A Reform in the Helium Purification System of the HTR-10: γ Dose Rate Measurement and Suggestions for Decommissioning