EUREX is a pilot fuel reprocessing facility, which ceased operation in 1984. During the recent flooding event in Northern Italy, on 16 October 2000. water entered the ventilation system and cable room, located 3m below ground level, causing the out-of-service of the system for some days. The water in the room was slightly contaminated by the radioisotopes contained in the ventilation system filters. The room, was emptied by transferring the water to the ponds. Anyway, the contamination levels are well below the allowed limits for discharge. The ventilation system was put back into service in a few days. Rating Justification: The event was initially rated at level 0 under the defence-in-depth approach (section IV-22.214.171.124), then upgraded to level 1, considering that a similar flooding event occurred in 1994 on the same facility (with less consequences), and in a nearby facility on the same site (with similar consequences to the ones experienced this year on the EUREX facility).