Gidds:
The one you are probably thinking of is in West Rutland VT near my old stomping grounds. Lots of people dive there. I was never allowed to dive there as a kid but I beleive Vtdiver2 has dove there and can tell you about it.
Yeah, I've dove this site many times, my brother lives near by.
Personally, I wouldn't drive from RI or CT to dive it, unless you are looking to practice cave diving. The quarry is "L" shaped and has 3 entries. One is a "beach" where you can walk in. It drops off down a steep slope to 25ft where an old 60's convertible sits. The other entries are doing a giant stride (about 5-6 ft above water level) from the side of the quarry, or climbing down the ladder into an old air shaft into the cave system ( normally the only way to dive it during winter when the rest of it freezes over).
From the convertible you can go down the steps, each 10 ft in depth and about 20 ft across. At 80 ft there is a bunch of vehicles, dumped over the past 30 years, as well as a snow machine and motorcycle. To the right in the quarry is a sheer wall, while on the left is the opening into the cave system. To be honest I haven't dove the caves, so I don't know a lot about them, but know it's large enough to drive vehicles in, has a series of guidelines in it, it goes back 100's of ft, and a dive died there this past summer diving the caves.
Issues with diving there. Vis can get bad at 70-75 ft, down to 2-3 ft. and local gangs like to use surrounding area for "target practice". If you want directions, let me know. Personally, I'd wait til spring, and come up and do it as part of a weekend trip to Vt, so you can do a couple of charters to the wrecks on Lake Champlain also. I can also get you info on them.
Hope this helps,
C-Dawg