Overview
- The utility released images on March 19 from an ultra-small drone survey inside Unit 3’s containment that began March 5 and captured the vessel bottom on March 17.
- Footage shows a large hole in the 14-centimeter-thick steel base of the roughly 5.5-meter-diameter pressure vessel, with sections melted and peeled back to expose internal structures.
- Lumpy material on control-rod drive equipment and nearby accumulations are described by TEPCO as likely melted fuel debris, with composition still under analysis.
- The 12-by-13-centimeter, 95-gram micro-drone provided the first close-up views of the pressure-vessel bottom in any of the three reactors that suffered meltdowns.
- TEPCO is converting the imagery into 3D data to reassess debris-removal methods and the schedule, acknowledging that the previous timeline for full decommissioning is now uncertain.