Two failed attempts to vent steam within days of the March 11 quake and tsunami most likely resulted in damage to the containment vessel of the Fukushima No. 1 power plant's No. 2 reactor, a Tokyo Electric Power Co. source said Wednesday.
This latest revelation casts further doubt on the crisis-management capabilities of the plant's operator, already put to shame by the release of massive amounts of radioactive material into the air and contaminated water into the ocean.
Venting is a procedure used to relieve pressure building up inside a reactor's containment vessel. Although the steam contains radioactive material, venting it prevents excessive pressure from damaging the containment vessel — a hazardous situation that would release extraordinary amounts of radioactive material into the environment.