Any discount programs for disabled? Golden age?

Each state has different rules for disabled discounts for their state parks. Some are only for residents of their state, some are for all disabled but vary in the amounts. The only way to find out is to go to each state park website and look at their rules and make a note of what their rules and requirements are. Georgia only gives discount for Georgia residents.
We have the America the Beautiful access pass and are using it a a Corps of Engineers park in Illinois.