Civil Geometry: Draw line tangent from and arc and perpendicular to another line

This is a rather simple thing to do with dumb lines, but I have yet to figure out how to make it work with Civil Geometry.

I want to draw the highlighted line below:

With dumb lines, its pretty easy; Draw line, tangent snap to the arc Traf Sep nose, perpendicular snap to the CL. 

I have never been able to figure out how to accomplish this using Civil Geometry. Does anyone know how to do this?