So I removed the base mount and found that the crack is originating from one of the mouting holes. In-fact there are several new cracks starting that are not visible when the base plate is covering the holes.
I guess the best course of action is to:
1. Use my dremel tool to chamfer out the holes more than I did originally to relieve the stress. Obviously I didn't chamfer them enough when I originally put in the tower.
2. Put super glue on the non-visible parts of the existing cracks to provide some additional strength and hopefully stop the progression.
3. Coat the entire edge of each hole with super glue to prevent chipping in the future.
3. Do the same thing on the other side even though there's no cracks on that side that I can see.
Any other suggestions?