I think two years is sufficient in virtually all cases. I have had many friends and colleagues comment on that question. I think the critical thing you have to start with is that when you are doing a review of a major project and you have two years, you are not trying to do the studies that are required. You're not trying to do the evaluations that are required. You are not trying to write reports. Those are already supposed to be available with all the information. If they're not, the clock stops and that is not included in the two years. The two years are to assess the information that is available, see if it's adequate, draw conclusions from it, and get public input. Two years is more than enough.
On May 30th, 2012. See this statement in context.