The USGS report FS-135-97 summarizes the BLM reports and historical data fairly well. Maximum salt crust thickness was 7 feet in 1960 and 5.5 feet in 1988. That is a loss of about 55 million tons of salt or about 5/8" per year per their own findings! At that rate during the 27 years since we should have 4.1 feet of salt crust with no Save the Salt efforts. Problem is the loss rate increases exponentially as the basin area decreases. I think Ron's right! It's GONE!
If you look on Google Earth it looks like there is a lot of salt on the other side of the interstate. These "ponds" are lined so you get ALL the salt when the water evaporates. All we need is a lined course pond - then the pumping will actually do something. How to get that? I suspect lawyers will have to be involved.
On a personal note my first visit was 1970 and the salt was very thick and very white. We had to drill pilot holes for awning stakes with our cordless drills. [You young guys will have to Google brace & bit!] In 1975 when I ran my Honda it was still very thick but very brown and rough. Mother Nature further aggravated the traction problem! I returned to the salt in 2007 and it looked pretty good at the time. Been there every year since but have seen conditions deteriorate rapidly since then! I helped Ron Main sell worthless salt mining stock at the LA Roadster show to build the dock at Land's End. Bought some myself! [BTW: More hot rodders walked by than stopped!] Last year at the Top Speed Meet I helped to drill about 1/3 of the holes for the course markers. When we started at about the 3 the salt was tough and about 1~2" thick. It took about 5 minutes with a masonry bit to get through it. We switched to a hammer drill and then just a few seconds. By the time we got to the nine you did not even need to turn on the drill - you could just lean on it and make a hole in the goo! Reconfirms the GONE theory!
In the meantime maybe Utah can block off half of I-80 and we can go 500 in the Utah/B'ville Three Mile!
