2016-04-26. 30 Years After Chernobyl Disaster, Shelter Nears Completion.

posted May 3, 2016, 10:00 AM by Alan Gould   [ updated May 3, 2016, 10:05 AM ]
By Henry Fountain. For GSS Energy Use chapter 4. Excerpt: On the night of April 26, 1986, engineers at the Chernobyl nuclear plant in what was then Soviet Ukraine performed a safety test at the plant’s No. 4 reactor. ...In a matter of seconds, power inside the uranium-and-graphite core of the reactor surged out of control, setting off a steam explosion that was followed by a fire that spewed radioactive particles into the atmosphere. ...several dozen plant workers and firefighters died in the immediate aftermath. Thousands more were sickened by radiation, over the short and long term. The surrounding countryside, contaminated by radioactive fallout, was declared off limits to anyone without a pass to get through security checkpoints. On the 30th anniversary of the accident, access within the 18-mile exclusion zone, ...is still restricted. ...An arched shelter designed to enclose the radioactive remains of the destroyed reactor is nearing completion ...being built — at a cost of at least $1.7 billion — to last 100 years. Inside, the radioactivity levels will be so high that normal maintenance, like painting, will not be possible. ...Inside the arch will be a heavy duty crane and other remote-operated equipment to be used to start removing the crumbling radioactive fuel that remains in Unit 4. ...There is a lot of fuel — 195 tons, by one estimate — along with tons of lead, sand and other materials that were dropped on the reactor by helicopter in a desperate effort to extinguish the fire. It all melted together into a lethal lava-like substance that poured through pipes and holes in the structure and solidified....  http://www.nytimes.com/2016/04/27/science/30-years-after-chernobyl-disaster-shelter-nears-completion.html