[TowerTalk] height of ground rod at tower base

[Jeff]

What does the NEC code (meaning a safety ground and not the more expansive 
proper lightning dissipation) for minimal grounding of a tower?

I need to get the rural county building inspectors out to look at my towers 
and want to show them something that they will have seen before with respect 
to a basic safety ground.  From what I understand locally that means a pair 
of ground rods in a configuration like what would be required at a house for 
the mains entry.

To that end I am unsure what the height of the ground rod should be in the 
NEC context?  Is the connection wire/rod joint to be made above grade, even 
with grade or below grade?

73/jeff/ac0c
www.ac0c.com
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