Is a 20 ft bare #2 AWG in the ground 30 in. deep connected to a nema 3 panel a ground ring according to code?

I missed the cold water ground because they used plastic tubing. I missed the concrete encased because the slab was poured already. Tried to get by with just a ground rod, AHJ would'nt accept. Never ran a ground ring before. Am I on the right path?