CBS reports:Toshiba designed these scorpions specifically to examine Unit 2's condition and to locate the melted uranium fuel within.The second robot Tokyo Electric Power Company (TEPCO) sent into Fukushima's unit 2 reactor also failed to finish its mission. Earlier this month, the cameras of the first "scorpion" robot that ventured into the reactor malfunctioned after two hours due to extremely high radiation levels. Now, it's the machine's left crawler belt that stopped working (PDF) altogether, forcing TEPCO to cut off its tether and to leave it inside.
The robot, carrying a dosimeter, thermometer and two small cameras, transmitted some data and visuals but could not locate melted fuel - key information to determine how to remove debris out of the reactor. The robot was abandoned inside the vessel at a location where it won’t block a future probe.
Preliminary examinations over the past few weeks have detected structural damage to planned robot routes and higher-than-expected radiation inside the Unit 2 containment chamber, suggesting the need to revise robot designs and probes.
Similar probes are being planned for the two other melted reactors. A tiny waterproof robot that can go underwater will be sent to Unit 1 in coming weeks, but experts haven’t figured out a way to access badly torn Unit 3.Perhaps uncoincidentally, the US nuclear power industry is stuck somewhere between stalled and tanking:
TEPCO needs to know the melted fuel’s exact location and condition and other structural damage in each of the three wrecked reactors to figure out the best and safest ways to remove the fuel.
Despite the incomplete probe missions, TEPCO stuck to its schedule to determine methods for the melted fuel removal this summer and start work in 2021, company spokesman Yuichi Okamura said.
On the other hand, nuclear disaster cleanup seems to be a growth industry.This was supposed to be America’s nuclear century.The Three Mile Island meltdown was two generations ago. Since then, engineers had developed innovative designs to avoid the kinds of failures that devastated Fukushima in Japan. The United States government was earmarking billions of dollars for a new atomic age, in part to help tame a warming global climate.But a remarkable confluence of events is bringing that to an end, capped in recent days by Toshiba’s decision to take a $6 billion loss and pull Westinghouse, its American nuclear power subsidiary, out of the construction business.The reasons are wide-ranging. Against expectations, demand for electricity has slowed. Natural-gas prices have tumbled, eroding nuclear power’s economic rationale. Alternative-energy sources like wind and solar power have come into their own.And, perhaps most significantly, attempts to square two often-conflicting forces — the desire for greater safety, and the need to contain costs — while bringing to life complex new designs have blocked or delayed nearly all of the projects planned in the United States.“You can make it go fast, and you can make it be cheap — but not if you adhere to the standard of care that we do,” said Mark Cooper of the Institute for Energy and the Environment at Vermont Law School, referring to the United States regulatory body, which is considered one of the most meticulous in the world. “Nuclear safety always undermines nuclear economics. Inherently, it’s a technology whose time never comes.”