Hydraulic Groundrod Driver

I used this method a few years back and found that it worked very quickly.

If you use an appropriately sized female garden hose repair coupler, such as http://www.homedepot.com/p/Ray-Padula-Metal-5-8-in-Garden-Hose-Female-Thread-Repair-with-Stainless-Steel-Clamps-RP-RIFR-6/205167514 and pound it into a piece of appropriately sized EMT, you'll have all that you need. I (lightly) held the EMT in a vice and inserted the nipple end of the coupler into the EMT. I inserted a ratchet socket into the female hose end of the coupler and used a hammer to tap the back of the socket so as to drive the nipple end into the EMT.

To install the ground rod, you simply turn on the water supply and start driving the 10' stick of EMT into the soil till you reach the desired depth. Turn off the water supply, remove the EMT and drop your ground rod. Once I have the rods at the desired depth, I once again used water to back fill some of the soil that was pushed up out of the hole by the water. Since I'm in central Florida & the soil is pretty sandy, I found that refilling the hole with soil around the ground rod works pretty well as there's a lot of resistance by the ground rod to being pulled back out by hand after back filling. And yeah... that's dirt at the entrance to the EMT. It hasn't been used in a while.