Design and installation of a radioactive filter leaching system at the Idaho Chemical Processing Plant

The operation of facilities at the Idaho Chemical Processing Plant (ICPP) of the Idaho National Engineering Laboratory involves handling radioactive, transuranic (TRU), hazardous materials and their mixtures. High-efficiency particulate air (HEPA) filters are used in the off-gas streams to prevent these materials from reaching the environment. Due to the increased cost and complexity of the disposal of these contaminated filters, a filter leaching system has been designed and installed at the New Waste Calcining Facility (NWCF), which is located at the ICPP. The filter leaching system uses heated nitric acid and an air sparge to remove TRU and hazardous materials from the filters to that only trace quantities remain. The radiation fields are also reduced sufficiently to allow the filters to be disposed of with reduced shielding requirements. This results in a significant cost savings and makes handling and disposal of the used filters easier