I'm casually wondering what the ecological impact of just dumping it into the Great Salt Lake or the Utah salt flats would be. Both are already so toxically salty that almost nothing is able to live there.
But there's also industry that extracts the salt from the Great Salt Lake, via evaporation. This shows that, if you've got salt to dump somewhere, there's actually a market for that. (That is, if it's pure. Others pointed out the problem of chemicals added to the salt water to make it easier to process.)