update:

water drained away, work area was dry enough to work on.
there was no cork gasket present at all.

Could not remove valve cover plate , stem and gate , it is supposed to lift right out, but after so long a period of NO MAINTENANCE being preformed, I have to believe that it is fused open from all the corrosion.

I will also need to drill and tap the bolt holes so i can at least bolt it down shut. Not looking forward to it.

This is why people should make sure proper maintenance schedules are followed. Had I been around , I would have, but i'm thinking that the last time the thing was maintained was about 30 years before i was born...

thank you all for your help and input.