Glad we met this weekend, fnfalman. I did the dive to the base of the buoy Sunday morning and hit 101 ft on a 2+ ft tide on both of my computers (Tec 2G and Nitek Duo). That would suggest it is 99 ft on a zero tide. However, I must say that the buoy was moved from its previous position and is slightly deeper than it used to be.
I don't normally do navigation in the park based on surface features. Before we descended that buoy anchor chain, I told Elena (mscelaneous here on SB) what I thought was an appropriate bearing to the Sujac. I got separated from her class, but they made it based on my bearing... and I didn't! I think I got disoriented due to stopping several times to film.
It was also interesting to try reaching the wreck of the Pisces (glassbottom boat). The "middle" boundary buoy anchor chain used to rest right on the wreck, then just outside it. When we descended the chain, the wreck was not within our vision. Looks like I need to relearn my navigation at the surface... but then I never use it anyway.