"The Department of Defense (DOD) established the Operation Tomodachi Registry (OTR) following the devastating March 11, 2011 earthquake and tsunami in Japan. These unfortunate events caused severe damage to the Fukushima Daiichi Nuclear Power Station, which resulted in the release of radiation into the environment. The OTR includes nearly 75,000 DOD-affiliated individuals who were on or near the mainland of Japan during the period from March 12, 2011 to May 11, 2011, along with their corresponding whole-body and thyroid radiation doses. Over 58,000 individuals were associated with one of 13 shore-based locations, which included DOD military installations and major cities where the majority of the DOD-affiliated population worked or lived. Nearly 17,000 individuals were associated with U.S. Navy fleet-based locations, which included the 25 U.S. Navy ships (and aircrew) in the area during this period. "
Environmental Health Surveillance Registries, Department of Defense: http://registry.csd.disa.mil/