Just wanted to update this thread with my experience last week. It was a surprisingly fun dive, 33 minutes to 20m / 65 ft., which is the most they'll let you do due to altitude (the pass back to Salt Lake is 2,170 m / 7,120ft.). There were quite a few platforms and lines, as well as a suspended wagon wheel that was excavated from the mud at the bottom. But the highlight was the warm water and cool mineral formations. Definitely bring a flashlight, though the DM, Jolie (sp?) brought one as well to highlight various features of the hole. Full rental gear and a dive-along (required if you don't have a buddy) was $78 with tax. Don't be fooled by Jolie's youthful appearance, she has cave training, a ton of experience, and did a great job, especially with my painfully slow descents. They didn't have DIN-convertible tanks but might be able to get some if you call ahead. Nothing corrosive in the water, but high mineral content. The early dives have the best viz, but midday is best for sunlight. Lots of people snorkeling as well, so a place to bring your kids.
It is pretty surprising that you can get "open" water certified in what is effectively a deep pool. I can hardly imagine coming out as such a student to California and having to deal with wetsuits, hoods, sand, surf, surface swims, current, boats, navigation, etc. I don't mean to start a discussion here, I guess that is why PADI makes such a big point that you should get a tour first before you start diving on your own in a new location.
Anyway, it was a great dive, and I would happily go back if I was in the area.
