(Kanagawa Shimbun: November 3, 2015 – p. 3)
In response to an inquiry from a citizen’s group, which pointed out that USS George Washington (GW) (CVN-73) possibly discharged radioactive substances into the ocean within Japan’s Exclusive Economic Zone (EEZ, 200 nautical miles from coast) while underway in March and April in 2011, the Ministry of Foreign Affairs (MOFA) replied in writing on Nov. 2. The ministry acknowledged that the aircraft carrier discharged radioactive substances into the ocean, but explained that the substances had no impact on the environment and that the discharge was conducted under safe conditions. The nuclear-powered GW was deployed to the U.S. Navy Yokosuka Base (Yokosuka City) until May.
The group is “The Citizen’s Association to Think about the Issue of Yokosuka as the Homeport of a Nuclear-powered Aircraft Carrier.” The association analyzed the GW’s logbook obtained under the U.S. Freedom of Information Act. According to its analysis, on April 8, 2011, the aircraft carrier released the reactor’s first-stage cooling water containing radioactive substances into waters off Shikoku. The association pointed out: “Although the spot is 225 nautical miles from the mainland, it is within 200 nautical miles from Torishima Island (Tokyo).”
The analysis also disclosed that while underway, the GW conducted training in which one of the two reactors was purposefully shut down and immediately restarted to full power, going back to normal operation through the critical point. The same process was repeated with the other reactor, according to the analysis.
As for the discharge of radioactive substances within 200 nautical miles, MOFA replied in writing: “The U.S. has explained to MOFA that the offshore release of radioactive substances at a spot more than 12 nautical miles from coast was conducted under strict conditions. MOFA understands that the discharge of low-level radioactivity has no impact on human health, marine organisms, or the environment.” Regarding the emergency power output training, MOFA said: “The design of the U.S. Navy’s reactor is different from that of a commercial reactor. The training is conducted under safe conditions.”
Masahiko Goto, a lawyer for the association, commented, “MOFA’s acknowledgement is a step forward. However, it is still questionable whether the U.S. side has fully provided information. The Japanese side should call on the U.S. military to provide concrete information and an explanation to citizens.” (Slightly Abridged)