To evaluate the performance of field-portable (360 mm Dx360 mm Hx800 mm W) and fixed-mount (1,880 mm Dx2,140 mm Hx9,085 mm W) filter presses for soil consolidation and volume reduction in the radiation-contaminated soil washing process, radiation assessment was conducted with soil from Fukushima contaminated with over 570,000 Bq/kg of radioactivity. The results were as follows. (1) During soil consolidation, the maximum core dose in the field-portable and fixed-mount types was evaluated respectively as 196 mu Sv/h and 60 mu Sv/h at the distance of 1 m from the core. (2) From these results, the maximum exposure dose in ordinary maintenance and inspection was evaluated as 48.1 mSv, exceeding the radiation protection guide level, and thus measures to reduce radiation exposure are required particularly in ordinary maintenance.