On the VA disability- I think you need to preorder the " America the beautiful" pass with your VA documents. Once in that pass will let you in, but i dont think they will let you in for free with out it - unless you are active military. ( this said i did see them waive someone through with a Base sticker in their windsheild - so maybe if you have that ? )
You can get your access pass at this park. Takes a few minutes and then spend the rest of the day enjoying the park!
You pay 25 per car but I'm sure they might help you with VA questions and yes you can access the park the same day..
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