Tokyo Electric Power Co. continues to learn more about just what happened at its Fukushima Daiichi nuclear plant after Japan’s 9.0-magnitude earthquake and tsunami this March.
Recent radiation measurements suggest hydrogen from a neighboring unit may be to blame for an explosion at unit 4. Meanwhile, workers recently inspected the interior of a containment vessel at the neighboring Fukushima Daini plant. Among the developments at Fukushima in the last week:
TEPCO: Hydrogen from Fukushima Daiichi Unit 3 May Have Caused Unit 4 Explosion
– Radiation measurements from exhaust pipes suggest an explosion at unit 4 likely was caused by hydrogen from unit 3, rather than from damage to spent fuel as many assumed in the early days of the crisis.
Varying radiation levels along piping leading to an exhaust stack shared by both units suggest steam and hydrogen flowed from unit 3 to unit 4. The later unit was down for inspection at the time of the earthquake, with all of its fuel in a spent-fuel storage tank. TEPCO and government officials initially feared water in the tank had boiled off, exposing fuel to air and creating hydrogen that exploded March 15. Subsequent inspections, though, showed the tank still contained water and the fuel was not extensively damaged.
Work Begins Inside Daini Containment
– Workers entered the containment vessel of a Fukushima Daini reactor Monday for the first time since the accident. A crew of 10 began taking radiation readings and visually inspecting unit 4 for damage caused by the earthquake, Kyodo reported. TEPCO also has plans to inspect the other three reactors at Daini, which was not damaged to near the degree as its sister plant, Fukushima Daiichi, six miles away.
New Prime Minister More Supportive of Nuclear Power
– Japan’s Parliament elected Yoshihiko Noda as prime minister Tuesday, replacing Naoto Kan amid criticism of his leadership following the devastating earthquake and nuclear crisis. Noda, known as a fiscal conservative, served as finance minister under the previous prime minister. Unlike his predecessor, he has called for the restart of reactors shut down around the country following the accident as Japan faces a looming power shortage.