What is the hardest part about decommissioning power plants?

Question: What is the hardest part about decommissioning power plants?
- Keywords:
  decommission,
  difficult,
  hard,
  plant,
  power
Asked by thecatcannon to Mark on 22 Mar 2011 in Categories: Your Research.
- Mark Vesey answered on 22 Mar 2011:
  
  The complexity and unknown factors. Many nuclear facilities weren’t built with decommissioning in mind and so it is difficult to do and safety is always the main concern.
  Newer power plants will be designed and built with decommissioning in mind and therefore in the future it shoudl be an easier, less timeconsuming, less complex process.

Question: What is the hardest part about decommissioning power plants?