250.56...the "25 ohm or less" requirement....good point, George!
And Irrellevant.
I sat "irrellevant" because this part of the code addresses the "grounding system." As the garage being discussed is a separate structure, and not a separate service....any ground rod driver would technically be supplimental to whatever there is at the main service.
Now, some may say 'but the garage is so far away.' In this case, "far" is a good thing. As documented in the American Electricians' handbook, as well as implied by the NEC requirement that supplimental electrodes be at least six feet away, the farther apart the ground rods are, the more evvective they are. Seems backwards, but there it is!
