It's certainly a large piece of land. As I said, it covers seven square kilometres. Decontaminating that much land is certainly a lot of work. I don't know what estimates or data they're looking at that would lead them to say that it will take that long.
If we want the site to be safe for everyone, the federal government must take responsibility. Only the government has information about the amount of contaminants, or at least it has access to the data that enables it to say it will take up to 30 years.