I received some disturbing information today. Radiation surveys showed dose rates of 827 millirem per hour at the site boundary. For perspective, these are typically <0.05 millirem per hour at a typical U.S. commercial reactor site boundary. At U.S. reactors, a whole body dose rate of 1000 millirem/hour requires special controls and these are locked areas with unique locks and keys.
Dose rates by one of the damaged reactor containment structures was 40 Rem per hour (40,000 millirem/hour). Health affects are usually assured with an acute exposure of 100 to 200 Rem, and some deaths can occur although most in that range survive. Acute is defined as receiving that radiation exposure in a 24 hour period. However these dose rates are not likely to spread beyond the site, so they would not endanger the public.
Beyond all the above, my most immediate concern is with the spent fuel pools being exposed to the atmosphere, which happened when the Reactor Building blowout panels "blew out" in the hydrogen explosions over the past few days. This is the equivalent of having your swimming pool filled with used nuclear fuel bundles. They lost FPC (Fuel Pool Cooling) which is causing this water to boil off and although those spent bundles have decayed and cooled over time, it is a tremendous amount of radioactive material with thousands of Curies of activity. This is what they are talking about using helicopters to drop water into.