Getting Depression Contours to Display

[Anonymous]

I am trying to get depression contours to display. I have created a circular depression (in the TIN model) around a surface inlet. I have set the depression contours to true and specified a tick mark interval and length in the surface style. I have changed the interval to 0.5 and they still didn't display.  I was able to get them to display by creating a rectangular depression.  I think it may be a function of the distance between TIN lines and the number of contours shown. If anyone can verify this or has a solution it will be greatly appreciated.  

[Joe-Bouza]

A peice if dwg would help

[Anonymous]

Here is a screen shot of the circular depression and the rectangular depression. Both areas are from the same surface.