TEPCO released a video showing a drilling rig, used in preparation for internal investigation of containment vessel No. 2 of Fukushima Daiichi Nuclear Power Station. The drilling was seated against the CRD hatch inside unit 2, the selected site where a robot will be inserted into unit 2 containment to collect data and images.
Due to shielding blocks difficult to remove and high radiation levels found where the hatch gasket had melted away, this work has been repeatedly delayed.
Logos from IRID, Toshiba and IHI are displayed on that drilling rig. IRID is the decommissioning research and development group. Toshiba handles the inspection and response work at the site and was a prime contractor at Daiichi before the disaster. IHI Corporation does a variety of high tech work including the energy and aerospace industries.
Little is known about the capabilities of that drilling rig. To conduct the containment inspection the workers will have to insert a robot into the CRD hatch tube.Earlier in the process it was decided to drill out an opening on the hatch rathen than trying to open it. In similar works at unit 1 a large tube shaped rig is connected to the containment port to act as a hot cell, to enable the robot to enter and exit the containment structure without having radiation or radioactive materials to escape.
Similar efforts at unit 1 involved connecting a large tube shaped rig to the containment port that acts as a hot cell. This allows the robot to enter and exit the containment structure without allowing radiation or radioactive materials to escape. Earlier practiced work at Unit 2 showed workers training with such a hot cell unit.
Asahi Shimbun had reported on September 2016 that TEPCO has announced they would begin the robotic containment inspection of unit 2’s containment in early 2017. This new development might be a sign that they have overcome the difficulties that caused delays since 2014.