Hey SparkyNC
Here is another way to look this. To prove that you have 25ohms or less to ground, you would have to drive a second rod to get the readings between them. Here in Georgia, we have to drive two rods also. I choose to drive them right below the drip line of the roof. Because of the moisture falling off the roof there, you're more likely to get a better ground for your grounding electrodes ( not to mention that the ground will be softer there too)!
Also, try driving your ground rods at about a 45 degree angle. The NEC will allow up to 45 degrees on your rods. And last, I use a Bosch hammer with a ground rod bit to drive my rods. Not only wil it drive through rocks with ease, but it will also stop the end of the rod from mushrooming... thus allowing you to put your acorn clamp on after the rod is driven. The3 only downfall I have encountered has been the electrical inspector questioning me if I cut the rod off because the end of the rod looks new after I drive it.
Good luck, and I hope this will help you!
