Have you seen how the military votes? They already signed up.

Place your item in bagging area

The real issue is “Hole” is not desctiptive enough for a clear answer. A straw has one “Through Hole”. If you dig a hole in the ground you have one “Blind Hole”.

Really good points. I was only thinking of the structure of the concrete… Sea life growth is a whole other ball game!

There are 2000 year old Roman concrete piers that are still just hanging out in sea water. So it’s possible if you find the right mix.