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Excessive Radiation Inside Fukushima Fries Clean-Up Robot (gizmodo.com)
"A remotely-controlled robot sent to inspect and clean a damaged reactor at Japan's Fukushima nuclear plant had to be pulled early when its onboard camera went dark, the result of excess radiation," reports Gizmodo. "The abbreviated mission suggests that radiation levels inside the reactor are even higher than was reported last week -- and that robots are going to have a hell of a time cleaning this mess up." From the report: Last week, Gizmodo reported that radiation levels inside the containment vessel of reactor No. 2 at Fukushima reached a jaw-dropping 530 sieverts per hour, a level high enough to kill a human within seconds. Some Japanese government officials questioned the reading because Tokyo Electric Power Company Holding (TEPCO) calculated it by looking at camera interference on the robot sent in to investigate, rather than measuring it directly with a geiger counter or dosimeter. It now appears that this initial estimate may have been too low. Either that, or TEPCO's robot is getting closer to the melted fuel -- which is very likely. High radiation readings near any of the used fuel are to be expected. Yesterday, that same remotely operated robot had to be pulled when its camera began to fail after just two hours of exposure to the radiation inside the damaged reactor. Accordingly, TEPCO has revised its estimate to about 650 sieverts per hour, which is 120 more sieverts than what was calculated late last month (although the new estimate comes with a 30 percent margin of error). The robot is designed to withstand about 1,000 accumulated sieverts, which given the failure after two hours, jibes well with the camera interference. This likely means that the melted fuel burned through its pressure vessel during the meltdown in March of 2011, and is sitting somewhere nearby.
https://www.stripes.com/news/16-us-ships-that-aided-in-operation-tomodachi-still-contaminated-with-radiation-1.399094
You don't know what you're talking about again, Kendall.
Random suggestion--
Use a trailing fiber optic pickup, with the actual CCD and robot controller hardware OUTSIDE the reactor.
Similar in concept to the imaging system used for laparoscopy.
In this case, the "mobile" portion of the robot is made using the "more radiation resistant" larger discrete components, with a fat data cable and fiber optic line dragging behind it, leading to the actual logic controller portion of the robot, parked outside.
That would help with costs, and service life of the robot. (Expensive controller hardware stays outside the reactor, only the driver part needs to be discarded as radioactive waste, and the imaging sensor array is not inside the reactor.)
It's an onion of bullshit opposed by bullshit, though. Nuclear is fundamentally rather cheap and rather clean, using sane designs (not designs where it fucking melts into oblivion if it doesn't have constant active cooling, jesus christ what is wrong with those people), and using reasonable accounting based on rational pollution opportunity cost comparisons.
That is true *fundamentally*. In practice, nuclear has to spend so much on safety as to cause less than 1/100th the deaths of fossil fuels and even then people are still completely terrified over non-events (from a harm to human life standpoint) like Three Mile Island, people talk ominously about half-lives without ever once mentioning phrases like "Love Canal" or "Centralia" as points of comparison, economical designs are opposed by blowhards like Carter, etc.
It's worth focusing on alternatives mostly because there's too much bullshit to cut through, too many misconceptions and assholes protecting their jobs to make nuclear reform realistic. Unfortunately, there's not an ideal drop-in replacement for nuclear, particular not for larger megaproject sizes that could put a serious dent in pollution whilst simultaneously raising capacity and lowering costs in anticipation of the electric automobile revolution. Maybe they could drop a huge geothermal plant in Yellowstone... yeah, I'm sure the Greens would be perfectly OK with that, if it meant stopping global warming.