Mercuric nitrate, Hg(NO3)2, was introduced into the Hanford flowsheet when it was used to catalyze nitric acid dissolution of certain aluminum alloy fuels and to suppress radioiodine volatilization during nitric acid dissolution of short-cooled uranium metal fuel. Inventory estimates, based primarily on Hanford process-knowledge, suggest a total mercury inventory of 2,100 kg 1 in the Hanford Tank Farms. Aside from the obvious human exposure concerns via tank vapors, mercury species in the tank waste liquid and solid fraction pose risk to the implementation and execution of the River Protection Project mission due to mercury limits imposed under waste acceptance criteria, toxicity characteristic leaching procedure restrictions for secondary waste disposal, and air emission permits. Although there is currently no processing of tank waste at Hanford, waste processing is imminent and representative mercury inventory tracking will be important to anticipate and mitigate stack emissions and secondary liquid waste disposal issues like those experienced at the Savannah River Site.
Revised: January 8, 2019 |
Published: September 30, 2018