Fission fears

Japan's damaged Daiichi Nuclear Power Station in Fukushima is making headlines again after plant operator Tokyo Electric Power Company (Tepco) reported findings of small amounts of radioactive Xenon 133 and Xenon 135, byproducts of nuclear fission, in reactor 2. The company has begun adding boric acid to the cooling water there. Boric acid is used in nuclear reactors to slow down neutrons released in fission and thus reduce the risk of a nuclear reaction.

Xenon was detected after thorough testing of samples of radio active materials recently removed from inside the containment vessel of reactor 2.

A Tepco spokesperson emphasized that the small amount of Xenon is no indication of a larger meltdown. Temperature and pressure values have remained stable and there has been no increase in radioactive leakage.

This was also confirmed by the Japanese Atomic Energy Agency, which is closely monitoring the situation.

The emergence of Xenon and the resulting increased threat of a nuclear reaction could become an obstacle for the Japanese government and its plans to have the damaged power plant under control by the end of the year.

After the earthquake and tsunami of March 11, cooling units inside the Fukushima 1 Nuclear Power Station shut down, causing the fuel rods in reactors 1, 2 and 3 to either partially or completely melt. Hydrogen explosions caused further damage to the buildings. In the ensuing months, workers at the plant were able to slowly cool down the rods using large amounts of seawater; in the past weeks, they have managed to get temperatures in the pressure chambers down to below 100 degrees Celsius – the first step in plant stabilization. Tepco has also been able to reduce radioactive leakage by covering up reactor 1.

Author: Peter Kujath / Sarah Berning (dpa, Reuters)
Editor: Manasi Gopalakrishnan