AUSTRALIAN NUCLEAR FORUM INFORMATION PAPER NO.6 Health Effects of Major Nuclear Power Plant Accidents (Issued 19/12/03; Updated 23/7/12)

Daiichi in Japan are the most serious nuclear power plant accidents that have occurred in terms of potential public health consequences. This paper gives a brief summary of those consequences. Three Mile Island On 28 March 1979 at the No 2 Plant (TMI-2) (900MWe) there was a minor loss of steam generator feedwater flow that caused a reactor shutdown, but subsequent operator errors lead to a loss of coolant flow to the reactor core and the melting of about 1/3 of the reactor fuel. The accident was attributed to deficient operator training, although the plant design was such that made it more likely there would be such an accident (no more of this type have been built). Subsequently removal of the fuel was completed by 1991 and the plant placed in long-term monitored storage. The other similar reactor on the same site, TMI-1 (800MWe) continues to operate today. The accident resulted in some radioactive gases from the melted fuel being vented from the plant. Subsequently, off-site radiation exposures within 16 km were determined to average 0.08 mSv (about the same as a chest X-ray) with a maximum of 1 mSv (about 1/3 of the annual natural background dose). A study of the 30,000 people who lived within 5 miles of th