[TowerTalk] Soil and Tiltover question

[wf3h@comcast.net]

Looking at putting up a 50' tiltover Rohn 25 tower with a Pro 67B at the top (OK no snickering).  The antenna weighs 100 lbs.  Questions:

1. I live in S. Arizona desert. Soil quality will affect the ability of the concrete to maintain a stable tower. How do I find out how the what the soil is here, and how it will affect the tower.

2. I know folks who've put big beams on tiltover Rohn 25, but want to make sure I won't have any problems with the physics. Is a 100 lb antenna OK here, with the rotator in the top section of the tower?

I may also put up a tiltover freestanding crank up. Any thoughts on the differences?

Thanks all....

Bob/WF3H