Ok so I have access to about 4-5" of bare GEC right before the first ground rod acorn clamp. And thanks to sparky806 after checking out 820.40 this is fair game to connect to, just like LK said.
So my new question is does anybody know of what kind of approved clamp/fastener I can use to bond the communications system ground to the 4" bare GEC?
Thanks for all the help!!