324 and 325 Building hot cell cleanout program: Decontamination of C-Cell

During FY 1989 the decontamination of C-Cell of Hanford's 324 Building was completed as part of the 324 and 325 Building Hot Cell Cleanout Program sponsored by the DOE Nuclear Energy's Surplus Facilities Management Program. The decontamination effort was completed using a series of remote and contact decontamination techniques. Initial radiation readings in C-Cell averaged 50 rad/hr and were reduced remotely to less than 200 mrad/hr using an alkaline foam cleaner followed by a 5000-psi water flush. Contact decontamination was then permissible using ultra high-pressure water, at 36,000 psi, further reducing the average radiation level in the cell to less than 86 mrem/hr. The approach used in decontaminating C-Cell resulted in a savings in radiation exposure of 87% and a cost savings of 39% compared to a hands-on procedure used in A-Cell, 324 Building in 1987. The radiation dose and the costs to achieve a 244-fold reduction in radiation contamination were 1.65 mrem per ft2 and $96 per ft2 of cell surface area. 14 figs., 4 tabs