by trendal » Fri 26 Aug 2005, 10:31:55
$this->bbcode_second_pass_quote('shakespear1', 'U')h, from what I recall from my Nuc. Eng. education days, those little neutrons and gammas do a bad number on the metal parts of the reactor. I do not know the retrofitting schedules or what they do, but I think that this would be a big issue with an old reactor plant.
Do we have a practicing Nuclear Eng. in the house?

Well I'm not a Nuclear Engineer...but you
are correct. Radioactivity of the building and reactor vessel is a
key reason for decomissioning nuclear plants.
As you said, neutrons from the reaction stream out of the reactor at a more or less constant rate. Those neutrons smash into atoms in the surrounding reactor components and building materials. Sometimes these neutrons cause atoms in said materials to become radioactive. Over time, this builds up until some parts of the plant cane be
quite radioactive.
When they decomission an old plant, it isn't just the nuclear fuel itself that has to be stored in radioactive dump sites...
the building itself has to be painstakingly disassembled, packed into lead containers, and burried somewhere to be (hopefully) forgotten for a few hundred thousand years.