It does not look like there will be a dive this fall. I was hoping that I could round up some military guys but it just won't happen this fall. Still not too late to go for a dive but I don't have much time to dedicate to this right now.
On the other hand, my fireplace is coming pretty good. The concrete core is done and the next phase will be the rock finish exterior shell. Walls when finished with rock will be greater than 12 inches thick. Height of top of steel cover is 13ft from ground.