Title: TEPCO’s failure at math may have increased radiation release at Fukushima plant
Source: AJW by The Asahi Shimbun
Author: TOSHIHIRO OKUYAMA
Date: June 05, 2013
Workers miscalculated pressure levels inside a reactor during the early stages of the Fukushima nuclear crisis, leading to a reduction in cooling water and a possible increase in the volume of radioactive materials released.
Tokyo Electric Power Co. estimated the pressure inside the No. 2 reactor containment vessel at 400 kilopascals [...]
The actual pressure was 40 kilopascals, far below the 101 kilopascals of the surrounding atmosphere, suggesting that a large amount of radioactive materials escaped from the reactor.
TEPCO later discovered the mistake but did not announce it. [...]
“I think the airtightness (of the containment vessel) has not been maintained,” [Tadayuki Yokomura] said, according to a video footage of a TEPCO teleconference. [...]
The difficulty in venting fueled concerns that mounting pressure could rupture the containment vessel and release lethal levels of radioactive materials.
Early on March 15, TEPCO temporarily evacuated all but the minimum required 70 or so workers from the plant compound. [...]
See also: NHK: "The unimaginable was happening" -- Workers say part of Reactor 2 containment vessel destroyed -- After alarming pressure readings, "we heard a loud bang... pressure is now zero" (VIDEO)
Published: June 5th, 2013 at 5:19 pm ET