You are not going to be able to do AN/DP in a 55 ft deep quarry. If it's through TDI the cert is good to 150 ft. A minimum of 6 dives are required and at least two must be in excess of 100 ft. If Millbrook only went to 95 you'd have to go somewhere else for at last two of those dives. When I teach it I do seven dives minimum with 4 of them in excess of 100 ft. At least two are in the 120-130 range so it does limit my choices. Fortunately I have Gilboa only 4 hours away.
I never said we were going to do ALL our training dives there. We are going to do a fair number of training dives, though (already done 5 training dives and there are 5 or 6 more dive DAYS scheduled), and some of them were going to be at Millbrook.