Just for the heck of it, I'll defend my semantics. Yup... DUSEL was proposed in the early 2000s right after Homestake shutdown. And the key being, using that site "as an underground science laboratory". Prior to that, it was indeed used... "as a goldmine" (with some science on the side). So it indeed seemed like a 'new' proposal.
As the NSF was asking for RFPs at the time, there were three or four contenders (a new mine in Colorado, and an existing mine in MN, and of course Homestake). At the time, Homestake had a lot of positive elements, but also some serious problems (ownership, EPA liability, and many thousands of vertical feet of water). So, at the time it was only a "possibility", and far from a sure thing that DUSEL would ever come to fruition. I would speculate that even today, given the nature of science funding and grants... it's still a bit touch and go.