While there could be cheaper alternatives to vitrifying all low-activity radioactive waste at the Hanford Site in Washington state, the Energy Department should do more vetting before committing to one or more of those options, according to a new assessment from a National Academies of Sciences, Engineering, and Medicine panel.
The fiscal 2017 National Defense Authorization Act required the National Academies to review another study ordered by Congress, led by the Savannah River National Laboratory, into supplemental methods to treat the low-activity waste stored in underground tanks at Hanford. That is because the Waste Treatment Plant (WTP) being built by Bechtel National lacks capacity to convert all 56 million gallons of radioactive tank waste at the site into a stable glass-like substance.
While the 10% of the material that is high-level radioactive waste (HLW) will be made into glass, only one-third to half of the LAW will vitrified during the plant’s 40 to 50 years of operation, the National Academies said in its assessment of the SRNL report.
The remaining material, dubbed supplemental low-activity waste, could be handled in various ways, the research and development center at SRNL concluded earlier this year:
- Using additional vitrification technology could take 10 to 15 years to implement and cost $20 billion to $36 billion.
- Grouting the material into a concrete-like substance would cost $2 billion to $8 billion, and take eight to 13 years.
- Finally, using fluidized bed steam reforming technology could take 10 to 15 years and cost $6 billion to $17 billion.
The April preliminary study by SRNL also says construction and testing lead times for one or more of the options would “require an immediate start” in order to meet the Energy Department’s 2034 target date for beginning treatment of the supplemental LAW that cannot be handled at the Waste Treatment Plant.
The National Academies review concludes that while the SRNL report “provides useful steps forward in assessing the options,” it does not yet provide a complete technical basis needed to support a final decision on a treatment approach.
