Demolition may start soon on Hanford's most hazardous building
http://www.tri-cityherald.com/news/local/hanford/article106593777.html
Actually kind of a toss up whether PFP or Purex would be the most hazardous. Both are nasty levels of contamination.
Purex will be a nightmare because of the hot cells alone. It's also a much larger building than PFP with a lot more piping and ducting. IMHO of course.