The U.S. 7th Fleet has temporarily repositioned its ships and aircraft away from the Fukushima Dai-Ichi Nuclear Power Plant after
detecting low level contamination in the air and on its aircraft operating in the area. The source of this airborne radioactivity is a radioactive plume released from the Fukushima Dai-Ichi Nuclear Power Plant.
For perspective, the maximum potential radiation dose received by any ship's force personnel aboard the ship when it passed through the area was less than the radiation exposure received from about one month of exposure to natural background radiation from
sources such as rocks, soil, and the sun.
The ship was operating at sea about 100 miles northeast of the power plant at the time.
Using sensitive instruments, precautionary measurements of three helicopter aircrews returning to USS Ronald Reagan after conducting disaster relief missions near Sendai identified low levels of radioactivity on 17 air crew members. The low level radioactivity was easily removed from affected personnel by washing with soap and water. They were subsequently surveyed, and no further contamination was detected.
As a precautionary measure, USS Ronald Reagan and other U.S. 7th Fleet ships conducting disaster response operations in the area have moved out of the downwind direction from the site to assess the situation and determine what appropriate mitigating actions are necessary.