Of all the giant mountains of mining waste I've visited...this is the first. Probably the last. But…read moredefinitely worth the visit, despite all the signs around warning of danger and strange smells leaking from vents in the ground. Otherwise, like many post-industrial sites, it has largely given over to nature, with lots of trees, birds, and deer.
The trail is mostly easy, gradually uphill, then suddenly very steep & rocky for the last 150 meters to the peak -- but you need to do that for the view.