1 Décembre 2015
December 1, 2015
A total of around 2,000 cables at two nuclear complexes were installed incorrectly according to fire prevention standards, the Tokyo Electric Power Co. (TEPCO) reported on Nov. 30.
There are an additional 500 locations at the complexes where problems with cables are suspected, and TEPCO is continuing to investigate these.
Under the Act on the Regulation of Nuclear Source Material, Nuclear Fuel Material and Reactors, cables used for the emergency shutdown of reactors and reactor cooling must be installed separately from other cables in order to limit the risk of fire spreading between the two. However, at the No. 1 through No. 7 reactors at the Kashiwazaki-Kariwa nuclear power plant there were 1,745 cables found to have problems such as the two types of cables being installed together. At the Fukushima No. 2 nuclear complex, there were 234 such cables found at the No. 3 and No. 4 reactors.
Furthermore, there were 748 places at the Kashiwazaki-Kariwa complex and 54 at the Fukushima No. 2 plant having problems with separation plates located between the two kinds of cables, such as there being holes in the plates.
Additionally, TEPCO revealed the results of an examination of 807 of its construction projects over the past five years, saying there were 735 cases of problems with construction supervision. The examination was prompted by a warning from the Nuclear Regulation Authority (NRA) that safety standards under the regulation act had been broken during safety-related construction at the Kashiwazaki-Kariwa plant.
TEPCO submitted both the reports on the cable problems and the supervision problems to the NRA on Nov. 30.